Antibodies that specifically bind a Bacillus thuringiensis toxin receptor

TECHNICAL FIELD

The invention relates to receptors that bind toxins from

Bacillus thuringiensis

and thus to pesticides and pest resistance. More particularly, the invention concerns recombinantly produced receptors that bind BT toxin and to their use in assays for improved pesticides, as well as in mediation of cell and tissue destruction, dissociation, dispersion, cell-to-cell association, and changes in morphology.

BACKGROUND ART

It has long been recognized that the bacterium

Bacillus thuringiensis

(BT) produces bactericidal proteins that are toxic to a limited range of insects, mostly in the orders Lepidoptera, Coleoptera and Diptera. Advantage has been taken of these toxins in controlling pests, mostly by applying bacteria to plants or transforming plants themselves so that they generate the toxins by virtue of their transgenic character. The toxins themselves are glycoprotein products of the cry gene as described by Höfte, H. et al.

Microbiol Rev

(1989) 53:242. It has been established that the toxins function in the brush border of the insect midgut epithelial cells as described by Gill, S. S. et al.

Annu Rev Entomol

(1992) 37:615. Specific binding of BT toxins to midgut brush border membrane vesicles has been reported by Hofmann, C. et al.

Proc Natl Acad Sci USA

(1988) 85:7844; Van Rie, J. et al.

Eur J Biochem

(1989) 186:239; and Van Rie, J. et al.

Appl Environ Microbiol

(1990) 56:1378.

Presumably, the toxins generated by BT exert their effects by some kind of interaction with receptors in the midgut. The purification of a particular receptor from

Manduca sexta

was reported by the present inventors in an article by Vadlamudi, R. K. et al.

J Biol Chem

(1993) 268:12334. In this report, the receptor protein was isolated by immunoprecipitating toxin-binding protein complexes with toxin-specific antisera and separating the complexes by SDS-PAGE followed by electroelution. However, to date, there has been no structural information concerning any insect receptor which binds BT toxin, nor have, to applicants' knowledge, any genes encoding these receptors been recovered.

DISCLOSURE OF THE INVENTION

The present invention is based, in part, on the isolation and characterization of a receptor that is bound by members of the BT-toxin family of insecticidal proteins, hereinafter the BT-R

1

protein. The present invention is further based on the isolation and characterization of a nucleic acid molecule that encodes the BT-toxin receptor, hereinafter BT-RBT-R

1

gene. Based on these observations, the present invention provides compositions and methods for use in identifying agents that bind to the BT-RBT-R

1

protein as a means for identifying insecticidal agent and for identifying other members of the BT-R

1

family of proteins.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1M

show the nucleotide sequence (SEQ ID NO:1) and deduced amino acid sequence (SEQ ID NO:2) of cDNA encoding the BT-R

1

protein from

M. sexta.

FIGS. 2A-2H

show the deduced amino acid sequence of cDNA encoding the BT-R

1

protein from

M. sexta

(SEQ ID NO:2).

FIG. 2I

shows a comparison of amino acid sequences of cadherin motifs (BTRcad-1 to 11) in BT-R

1

to those of other cadherins (SEQ ID NOS:8-11).

FIG. 3

shows a block diagram of the cadherin-like structure of BT-R

1

.

FIG. 4

shows the clone characterization of the BamHI-SacI fragment of BT-R

1

. LM is HindIII cut Lambda marker; UP is the uncut plasmid clone; NP is NsiI cut plasmid; XP is XhoI cut plasmid; BSP is BamHI and SacI cut plasmid showing the cloned fragment from BT-R

1

; RM is mRNA size marker; and RT1 and RT2 are transcribed mRNAs from the cloned BT-R

1

fragment.

FIG. 5

illustrates the detection of protein expression from the plasmid containing the Bam-Sac fragment of BT-R

1

using

35

S-methionine as a tag. LCR is a luciferase control mRNA to show that the rabbit reticulocyte lysates are functional; RR1 and RR2 are expression products of the Bam-Sac fragment of BT-R

1

produced in rabbit reticulocytes from mRNA; LCT is a luciferase control plasmid to show that the transcription/translation kit is functional; and TT1 and TT2 are expression products of the Bam-Sac fragment of BT-R

1

produced in a transcription/translation kit.

FIG. 6

shows a radio-blot of the Bam-Sac fragment of BT-R

1

with

125

I-labeled Cry1Ab. BBMV is the brush border membrane vesicles from the midgut of

M. sexta

containing the wild-type BT-R

1

receptor protein; RBK is a rabbit reticulocyte blank; RR1 and RR2 are the expression products of the Bam-Sac fragment of BT-R

1

produced in rabbit reticulocytes from mRNA; TBK is a transcription/translation kit blank; TT1 and TT2 are expression products of the Bam-Sac fragment of BT-R

1

produced in a transcription/translation kit. The arrows point to two of the bands.

FIG. 7

shows the presence of a BT-R

1

homologue in Pink Bollworm and European Corn Borer identified using toxin binding similar to that used to identify the original BT-R

1

clone.

FIG. 8

shows the binding of Cry1Ab to fragments of the BT-R

1

protein.

MODES OF CARRYING OUT THE INVENTION

I. General Description

The present invention is based, in part, on the isolation and characterization of a novel protein expressed in the midgut of

Manduca sexta

that binds to members of the BT-toxin family of proteins, hereinafter the BT-R

1

protein. The present invention specifically provides purified BT-R

1

, the amino acid sequence of BT-R

1

, as well as nucleotide sequences that encode BT-R

1

. The BT-R

1

protein and nucleic acid molecules can serve as targets in identifying insecticidal agents.

II. Specific Embodiments

A. BT-R

1

Protein

Prior to the present invention, although members of the BT-toxin family of protein were known, no one had identified the receptor that is bound by these toxin proteins. The present invention provides, in part, the amino acid sequences of a BT-toxin receptor that is expressed in the midgut of

Maduca sexta.

In one embodiment, the present invention provides the ability to isolate or produce a previously unknown protein by using known purification methods, the cloned nucleic acid molecules herein described or by synthesizing a protein having the amino acid sequence herein disclosed.

As used herein, BT-R

1

refers to a protein that has the amino acid sequence of BT-R

1

provided in

FIG. 1

, as well as allelic variants of the BT-R

1

sequence, and conservative substitutions mutants of the BT-R

1

sequence that have BT-R

1

activity. BT-R

1

is comprised of a single subunit, has a molecular weight of 210 kD, and has the amino acid sequence provided in

FIG. 1. A

prediction of the structure of BT-R

1

is provided in FIG.

3

.

The BT-R

1

protein of the present invention includes the specifically identified and characterized variant herein described, as well as allelic variants, conservative substitution variants and homologues (

FIG. 7

) that can be isolated/generated and characterized without undue experimentation following the methods outlined below. For the sake of convenience, all BT-R

1

proteins will be collectively referred to as the BT-R

1

proteins, the BT-R

1

proteins of the present invention or BT-R

1

.

The term “BT-R

1

” includes all naturally occurring allelic variants of the

Manduca sexta

BT-R

1

protein provided in FIG.

1

. In general, naturally occurring allelic variants of

Manduca sexta

BT-R

1

will share significant homology, at least 75%, and generally at least 90%, to the BT-R

1

amino acid sequence provided in Seq. ID No:2. Allelic variants, though possessing a slightly different amino acid sequence than Seq. ID No:2, will be expressed as a transmembrane protein in the digestive tract of an insect or other organism. Typically, allelic variants of the BT-R

1

protein will contain conservative amino acid substitutions from the BT-R

1

sequence herein described or will contain a substitution of an amino acid from a corresponding position in a BT-R

1

homologue (a BT-R

1

protein isolated from an organism other than

Manduca sexta

).

One class of BT-R

1

allelic variants will be proteins that share a high degree of homology with at least a small region of the amino acid sequence provided in Seq. ID No:2, but may further contain a radical departure from the sequence, such as a non-conservative substitution, truncation, insertion or frame shift. Such alleles are termed mutant alleles of BT-R

1

and represent proteins that typically do not perform the same biological functions as does the BT-R

1

variant of Seq. ID No:2.

The BT-R

1

proteins of the present invention are preferably in isolated form. As used herein, a protein is said to be isolated when physical, mechanical or chemical methods are employed to remove the BT-R

1

protein from cellular constituents that are normally associated with the protein. A skilled artisan can readily employ standard purification methods to obtain an isolated BT-R

1

protein. The nature and degree of isolation will depend on the intended use.

The cloning of the BT-R

1

encoding nucleic acid molecule makes it possible to generate defined fragments of the BT-R

1

proteins of the present invention. As discussed below, fragments of BT-R

1

are particularly useful in: generating domain specific antibodies; identifying agents that bind to toxin binding domain on BT-R

1

; identifying toxin-binding structures; identifying cellular factors that bind to BT-R

1

; isolating homologues or other allelic forms of BT-R

1

; and studying the mode of action of BT-toxins.

Fragments of the BT-R

1

proteins can be generated using standard peptide synthesis technology and the amino acid sequence of

Manduca sexta

BT-R

1

disclosed herein. Alternatively, as illustrated in Example 5, recombinant methods can be used to generate nucleic acid molecules that encode a fragment of the BT-R

1

protein. Fragments of the BT-R

1

protein subunits that contain particularly interesting structures can be identified using art-known methods such as by using an immunogenicity plot, Chou-Fasman plot, Garnier-Robson plot, Kyte-Doolittle plot, Eisenberg plot, Karplus-Schultz plot or Jameson-Wolf plot of the BT-R

1

protein. Fragments containing such residues are particularly useful in generating domain specific anti-BT-R

1

antibodies or in identifying cellular factors that bind to BT-R

1

. One particular fragment that is preferred for use in identifying insecticidal agents is a soluble fragment of BT-R

1

that can bind to a member of the BT family of toxins. In Example 5, a fragment of BT-R

1

that binds to a BT-toxin is disclosed.

As described below, members of the BT-R

1

family of proteins can be used for, but are not limited to: 1) a target to identify agents that bind to BT-R

1

, 2) a target or bait to identify and isolate binding partners and cellular factors that bind to BT-R

1

, 3) an assay target to identify BT-R

1

and other receptor-mediated activity, and 4) a marker of cells that express a member of the BT-R

1

family of proteins.

B. Anti-BT-R

1

Antibodies

The present invention further provides antibodies that bind BT-R

1

. The most preferred antibodies will selectively bind to BT-R

1

and will not bind (or will only bind weakly) to non-BT-R

1

proteins. Anti-BT-R

1

antibodies that are especially contemplated include monoclonal and polyclonal antibodies as well as fragments containing the antigen binding domain and/or one or more complement determining regions (CDRs) of these antibodies.

Antibodies are generally prepared by immunizing a suitable mammalian host using a BT-R

1

protein (synthetic or isolated), or fragment, in isolated or immunoconjugated form (Harlow, Antibodies, Cold Spring Harbor Press, NY (1989)). Regions of the BT-R

1

protein that show immunogenic structure can readily be identified using art-known methods. Other important regions and domains can readily be identified using protein analytical and comparative methods known in the art, such as Chou-Fasman, Garnier-Robson, Kyte-Doolittle, Eisenberg, Karplus-Schultz or Jameson-Wolf analysis. Fragments containing these residues are particularly suited in generating specific classes of anti-BT-R

1

antibodies. Particularly useful fragments include, but are not limited to, the BT-toxin binding domain of BT-R

1

identified in Example 5.

Methods for preparing a protein for use as an immunogen and for preparing immunogenic conjugates of a protein with a carrier such as BSA, KLH, or other carrier proteins are well known in the art. In some circumstances, direct conjugation with reagents such as carbodiimide may be used; in other instances linking reagents like those supplied by Pierce Chemical Co., Rockford, Ill., may be effective.

Administration of a BT-R

1

immunogen is conducted generally by injection over a suitable time period in combination with a suitable adjuvant, as is generally understood in the art. During the immunization schedule, titers of antibodies can be taken to determine adequacy of antibody formation.

Although the polyclonal antisera produced in this way may be satisfactory for some applications, for many other applications, monoclonal antibody preparations are preferred. Immortalized cell lines which secrete a desired monoclonal antibody may be prepared using the standard method of Kohler and Milstein or modifications which effect immortalization of lymphocytes or spleen cells, as is generally known. The immortalized cell lines secreting the desired antibodies are screened by immunoassay in which the antigen is the BT-R

1

protein or BT-R

1

fragment. When the appropriate immortalized cell culture secreting the desired antibody is identified, the cells can be cultured either in vitro or by production in ascites fluid.

The desired monoclonal antibodies are then recovered from the culture supernatant or from the ascites supernatant. Fragments of the monoclonals or the polyclonal antisera which contain the immunologically significant portion can be used as antagonists, as well as the intact antibodies. Use of immunologically reactive fragments, such as the Fab, Fab′, of F(ab′)

2

fragments is often preferable, especially in a therapeutic context, as these fragments are generally less immunogenic than the whole immunoglobulin.

The antibodies or fragments may also be produced, using current technology, by recombinant means. Regions that bind specifically to the desired regions of the BT-R

1

protein can also be produced in the context of chimeric or CDR grafted antibodies of multiple species origin.

As described below, anti-BT-R

1

antibodies are useful as modulators of BT-R

1

activity, are useful in in vitro and in vivo antibody based assays methods for detecting BT-R

1

expression/activity, in generating toxin conjugates, for purifying homologues of

Manduca sexta

BT-R

1

, in generating anti-ideotypic antibodies that mimic the BT-R

1

protein and in identifying competitive inhibitors of BT-toxin/BT-R

1

interactions. Also described are antibodies that specifically bind to fragments of BT-R

1

, for example, an antibody that specifically binds to an epitope located within the 232 C-terminal amino acids of the BT-toxin receptor depicted in SEQ ID NO:2.

C. BT-R

1

Encoding Nucleic Acid Molecules

As described above, the present invention is based, in part, on isolating nucleic acid molecules from

Manduca sexta

that encode BT-R

1

. Accordingly, the present invention further provides nucleic acid molecules that encode the BT-R

1

protein, as herein defined, preferably in isolated form. For convenience, all BT-R

1

encoding nucleic acid molecules will be referred to as BT-R

1

encoding nucleic acid molecules, the BT-R

1

genes, or BT-R

1

. The nucleotide sequence of the

Manduca sexta

nucleic acid molecule that encodes one allelic form of BT-R

1

is provided in FIG.

1

.

As used herein, a “nucleic acid molecule” is defined as an RNA or DNA molecule that encodes a peptide as defined above, or is complementary to a nucleic acid sequence encoding such peptides. Particularly preferred nucleic acid molecules will have a nucleotide sequence identical to or complementary to the

Manduca sexta

DNA sequences herein disclosed. Specifically contemplated are genomic DNA, cDNAs, synthetically prepared DNAs, and antisense molecules, as well as nucleic acids based on an alternative backbone or including alternative bases, whether derived from natural sources or synthesized. A skilled artisan can readily obtain these classes of nucleic acid molecules using the herein described BT-R

1

sequences. However, such nucleic acid molecules, are defined further as being novel and unobvious over any prior art nucleic acid molecules encoding non-BT-R

1

proteins. For example, the BT-R

1

sequences of the present invention specifically excludes previously identified nucleic acid molecules that share only partial homology to BT-R

1

. Such excluded sequences include identified members of the cadhedrin family of proteins.

As used herein, a nucleic acid molecule is said to be “isolated” when the nucleic acid molecule is substantially separated from contaminant nucleic acid molecules that encode polypeptides other than BT-R

1

. A skilled artisan can readily employ nucleic acid isolation procedures to obtain an isolated BT-R

1

encoding nucleic acid molecule.

The present invention further provides fragments of the BT-R

1

encoding nucleic acid molecules of the present invention. As used herein, a fragment of a BT-R

1

encoding nucleic acid molecule refers to a small portion of the entire BT-R

1

sequence. The size of the fragment will be determined by its intended use. For example, if the fragment is chosen so as to encode the toxin binding domain of BT-R

1

identified in Example 5, then the fragment will need to be large enough to encode the toxin binding domain of the BT-R

1

protein. If the fragment is to be used as a nucleic acid probe or PCR primer, then the fragment length is chosen so as to obtain a relatively small number of false positives during probing/priming. Fragments of the

Manduca sexta

BT-R

1

gene that are particularly useful as selective hybridization probes or PCR primers can be readily identified from the entire BT-R

1

sequence using art-known methods.

Another class of fragments of BT-R

1

encoding nucleic acid molecules are the expression control sequence found upstream and downstream from the BT-R

1

encoding region found in genomic clones of the BT-R

1

gene. Specifically, tissue and developmental specific expression control elements can be identified as being 5′ to the BT-R

1

encoding region found in genomic clones of the BT-R

1

gene. Such expression control sequence are useful in generating expression vectors for expressing genes in the digestive tract of a transgenic organism. As described in more detail below, a skilled artisan can readily use the BT-R

1

cDNA sequence herein described to isolate and identify genomic BT-R

1

sequences and the expression control elements found in the BT-R

1

gene.

Fragments of the BT-R

1

encoding nucleic acid molecules of the present invention (i.e., synthetic oligonucleotides) that are used as probes or specific primers for the polymerase chain reaction (PCR), or to synthesize gene sequences encoding BT-R

1

proteins, can easily be synthesized by chemical techniques, for example, the phosphotriester method of Matteucci, et al.,

J Am Chem Soc

(1981) 103:3185-3191, or using automated synthesis methods. In addition, larger DNA segments can readily be prepared by well known methods, such as synthesis of a group of oligonucleotides that define various modular segments of the BT-R

1

gene, followed by ligation of oligonucleotides to build the complete modified BT-R

1

gene.

The BT-R

1

encoding nucleic acid molecules of the present invention may further be modified so as to contain a detectable label for diagnostic and probe purposes. As described above, such probes can be used to identify nucleic acid molecules encoding other allelic variants or homologues of the BT-R

1

proteins and as described below, such probes can be used to identify the presence of a BT-R

1

protein as a means for identifying cells that express a BT-R

1

protein. A variety of such labels are known in the art and can readily be employed with the BT-R

1

encoding molecules herein described. Suitable labels include, but are not limited to, biotin, radiolabeled nucleotides, biotin, and the like. A skilled artisan can employ any of the art-known labels to obtain a labeled BT-R

1

encoding nucleic acid molecule.

D. Isolation of Other BT-R

1

Encoding Nucleic Acid Molecules

The identification of the BT-R

1

protein from

Manduca sexta

and the corresponding encoding nucleic acid molecules, has made possible the identification of and isolation of: 1) BT-R

1

proteins from organisms other than

Manduca sexta

, hereinafter referred to collectively as BT-R

1

homologues, 2) other allelic and mutant forms of the

Manduca sexta

BT-R

1

protein (described above), and 3) the corresponding genomic DNA that contains the BT-R

1

gene. The most preferred source of BT-R

1

homologues are insects, the most preferred being members of the Lepidopteran, Coleopteran and Dipteran orders of insects. Evidence of the existence of BT-R

1

homologues is provided in FIG.

7

.

Essentially, a skilled artisan can readily use the amino acid sequence of the

Manduca sexta

BT-R

1

protein to generate antibody probes to screen expression libraries prepared from cells and organisms. Typically, polyclonal antiserum from mammals such as rabbits immunized with the purified protein (as described above) or monoclonal antibodies can be used to probe an expression library, prepared from a target organism, to obtain the appropriate coding sequence for a BT-R

1

homologue. The cloned cDNA sequence can be expressed as a fusion protein, expressed directly using its own control sequences, or expressed by constructing an expression cassette using control sequences appropriate to the particular host used for expression of the enzyme.

Alternatively, a portion of the BT-R

1

encoding sequence herein described can be synthesized and used as a probe to retrieve DNA encoding a member of the BT-R

1

family of proteins from organisms other than

Manduca sexta

, allelic variants of the

Manduca sexta

BT-R

1

protein herein described, and genomic sequence containing the BT-R

1

gene. Oligomers containing approximately 18-20 nucleotides (encoding about a 6-7 amino acid stretch) are prepared and used to screen genomic DNA or cDNA libraries to obtain hybridization under stringent conditions or conditions of sufficient stringency to eliminate an undue level of false positives.

Additionally, pairs of oligonucleotide primers can be prepared for use in a polymerase chain reaction (PCR) to selectively amplify/clone a BT-R

1

-encoding nucleic acid molecule, or fragment thereof. A PCR denature/anneal/extend cycle for using such PCR primers is well known in the art and can readily be adapted for use in isolating other BT-R

1

encoding nucleic acid molecules. Regions of the

Manduca sexta

BT-R

1

gene that are particularly well suited for use as a probe or as primers can be readily identified by one skilled in the art.

Non-

Manduca sexta

homologues of BT-R

1

, naturally occurring allelic variants of the

Manduca sexta

BT-R

1

gene and genomic BT-R

1

sequences will share a high degree of homology to the

Manduca sexta

BT-R

1

sequence herein described. In general, such nucleic acid molecules will hybridize to the

Manduca sexta

BT-R

1

sequence under high stringency. Such sequences will typically contain at least 70% homology, preferably at least 80%, most preferably at least 90% homology to the

Manduca sexta

BT-R

1

sequence of Seq. ID No:1.

In general, nucleic acid molecules that encode homologues of the

Manduca sexta

BT-R

1

protein will hybridize to the

Manduca sexta

BT-R

1

sequence under stringent conditions. “Stringent conditions” are those that (1) employ low ionic strength and high temperature for washing, for example, 0.015 M NaCl/0.0015M sodium titrate/0.1% SDS at 50° C., or (2) employ during hybridization a denaturing agent such as formamide, for example, 50% (vol/vol) formamide with 0.1% bovine serum albumin/0.1% Ficoll/0.1% polyvinylpyrrolidone/50 mM sodium phosphate buffer at pH 6.5 with 750 mM NaCl, 75 mM sodium citrate at 42° C. Another example is use of 50% formamide, 5×SSC (0.75M NaCl, 0.075 M sodium citrate), 50 mM sodium phosphate (pH 6.8), 0.1% sodium pyrophosphate, 5× Denhardt's solution, sonicated salmon sperm DNA (50 μg/ml), 0.1% SDS, and 10% dextran sulfate at 42° C., with washes at 42° C. in 0.2×SSC and 0.1% SDS. A skilled artisan can readily determine and vary the stringency conditions appropriately to obtain a clear and detectable hybridization signal.

The presence of similar receptors in noninsect organisms as well as other insects besides those harboring BT-R

1

is supported by the sequence similarity of the BT-R

1

protein to that of the various members of the cadherin superfamily of proteins, which are membrane glycoproteins believed to mediate calcium-dependent cell aggregation and sorting. See, for example, Takeichi, M.

Science

(1991) 251:1451; and Takeichi, M.

N Rev Biochem

(1990) 59:237.

Included in this superfamily are desmoglien, desmocollins, the Drosophila fat tumor suppressor,

Manduca sexta

intestinal peptide transport protein and T-cadherin. All of these proteins share common extracellular motifs although their cytoplasmic domains differ. Goodwin, L. et al.

Biochem Biophys Res Commun

(1990) 173:1224; Holton, J. L. et al.

J Cell Sci

(1990) 97:239; Bestal, D. J.

J Cell Biol

(1992) 119:451; Mahoney, P. A. et al.

Cell

(1991) 853; Dantzig, A. H. et al.

Science

(1994) 264:430; and Sano, K. et al.

EMBO J

(1993) 12:2249. Inclusion of BT-R

1

in the cadherin superfamily is further supported by the report that EDTA decreases the binding of CryIAb toxin of BT to the 210 kD receptor of

M. sexta

(Martinez-Ramirez, A. C. et al.

Biochm Biophys Res Commun

(1994) 201:782).

It is noted below that the amino acid sequence of BT-R

1

reveals that a calcium-binding motif is present. This is consistent with the possibility that cells having receptors to bind toxin may themselves survive although they render the tissues in which they are included permeable to solutes and thus effect disintegration of the tissue. Such a mechanism is proposed for the death of insects that ingest the toxin via the epithelial cells in their midgut by Knowles, B. H. et al.

Biochim Biophys Acta

(1987) 924:509. Such a mechanism is also supported in part by the results set forth in Example 4 hereinbelow which indicate that the effect of the toxin on embryonic 293 cells modified to express the receptor at their surface is reversible.

E. rDNA Molecules Containing a BT-R

1

Encoding Nucleic Acid Molecule

The present invention further provides recombinant DNA molecules (rDNAs) that contain a BT-R

1

encoding sequences as herein described, or a fragment thereof, such as a soluble fragment of BT-R

1

that contains the BT-toxin binding site. As used herein, a rDNA molecule is a DNA molecule that has been subjected to molecular manipulation in vitro. Methods for generating rDNA molecules are well known in the art, for example, see Sambrook et al.,

Molecular Cloning

(1989). In the preferred rDNA molecules of the present invention, a BT-R

1

encoding DNA sequence that encodes a BT-R

1

protein or a fragment of BT-R

1

, is operably linked to one or more expression control sequences and/or vector sequences.

The choice of vector and/or expression control sequences to which the BT-R

1

encoding sequence is operably linked depends directly, as is well known in the art, on the functional properties desired, e.g., protein expression, and the host cell to be transformed. A vector contemplated by the present invention is at least capable of directing the replication or insertion into the host chromosome, and preferably also expression, of the BT-R

1

encoding sequence included in the rDNA molecule.

Expression control elements that are used for regulating the expression of an operably linked protein encoding sequence are known in the art and include, but are not limited to, inducible promoters, constitutive promoters, secretion signals, enhancers, transcription terminators and other regulatory elements. Preferably, an inducible promoter that is readily controlled, such as being responsive to a nutrient in the host cell's medium, is used. Further, for soluble fragments, it may be desirable to use secretion signals to direct the secretion of the BT-R

1

protein, or fragment, out of the cell.

In one embodiment, the vector containing a BT-R

1

encoding nucleic acid molecule will include a prokaryotic replicon, i.e., a DNA sequence having the ability to direct autonomous replication and maintenance of the recombinant DNA molecule intrachromosomally in a prokaryotic host cell, such as a bacterial host cell, transformed therewith. Such replicons are well known in the art. In addition, vectors that include a prokaryotic replicon may also include a gene whose expression confers a detectable marker such as a drug resistance. Typical bacterial drug resistance genes are those that confer resistance to ampicillin or tetracycline.

Vectors that include a prokaryotic replicon can futher include a prokaryotic or viral promoter capable of directing the expression (transcription and translation) of the BT-R

1

encoding sequence in a bacterial host cell, such as

E. coli

. A promoter is an expression control element formed by a DNA sequence that permits binding of RNA polymerase and transcription to occur. Promoter sequences compatible with bacterial hosts are typically provided in plasmid vectors containing convenient restriction sites for insertion of a DNA segment of the present invention. Typical of such vector plasmids are pUC8, pUC9, pBR322 and pBR329 available from Biorad Laboratories (Richmond, Calif.), pPL and pKK223 available from Pharmacia, Piscataway, N.J.

Expression vectors compatible with eukaryotic cells, preferably those compatible with vertebrate cells, can also be used to variant rDNA molecules that contain a BT-R

1

encoding sequence. Eukaryotic cell expression vectors are well known in the art and are available from several commercial sources. Typically, such vectors are provided containing convenient restriction sites for insertion of the desired DNA segment. Typical of such vectors are PSVL and pKSV-10 (Pharmacia), pBPV-1/pML2d (International Biotechnologies, Inc.), pTDT1 (ATCC, #31255), the vector pCDM8 described herein, and the like eukaryotic expression vectors.

Eukaryotic cell expression vectors used to construct the rDNA molecules of the present invention may further include a selectable marker that is effective in an eukaryotic cell, preferably a drug resistance selection marker. A preferred drug resistance marker is the gene whose expression results in neomycin resistance, i.e., the neomycin phosphotransferase (neo) gene. Southern et al.,

J Mol Anal Genet

(1982) 1:327-341. Alternatively, the selectable marker can be present on a separate plasmid, and the two vectors are introduced by cotransfection of the host cell, and selected by culturing in the presence of the appropriate drug for the selectable marker.

F. Host Cells Containing an Exogenously Supplied BT-R

1

Encoding Nucleic Acid Molecule

The present invention further provides host cells transformed with a nucleic acid molecule that encodes a BT-R

1

protein of the present invention, either the entire BT-R

1

protein or a fragment thereof. The host cell can be either prokaryotic or eukaryotic. Eukaryotic cells useful for expression of a BT-R

1

protein are not limited, so long as the cell line is compatible with cell culture methods and compatible with the propagation of the expression vector and expression of a BT-R

1

gene. Preferred eukaryotic host cells include, but are not limited to, yeast, insect and mammalian cells, the most preferred being cells that do not natlirally express a BT-R

1

protein.

Any prokaryotic host can be used to express a BT-R

1

-encoding rDNA molecule. The preferred prokaryotic host is

E. coli.

Transformation of appropriate cell hosts with an rDNA molecule of the present invention is accomplished by well known methods that typically depend on the type of vector used and host system employed. With regard to transformation of prokaryotic host cells, electroporation and salt treatment methods are typically employed, see, for example, Cohen et al.,

Proc Acad Sci USA

(1972) 69:2110; and Maniatis et al.,

Molecular Cloning, A Laboratoly Manual

, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y. (1982). With regard to transformation of vertebrate cells with vectors containing rDNAs, electroporation, cationic lipid or salt treatment methods are typically employed, see, for example, Graham et al.,

Virol

(1973) 52:456; Wigler et al.,

Proc Natl Acad Sci USA

(1979) 76:1373-76.

Successfully transformed cells, i.e., cells that contain an rDNA molecule of the present invention, can be identified by well known techniques. For example, cells resulting from the introduction of an rDNA of the present invention can be cloned to produce single colonies. Cells from those colonies can be harvested, lysed and their DNA content examined for the presence of the rDNA using a method such as that described by Southern,

J Mol Biol

(1975) 98:503, or Berent et al.,

Biotech

(1985) 3:208 or the proteins produced from the cell assayed via an immunological method.

G. Production of a BT-R

1

Protein Using an rDNA Molecule

The present invention further provides methods for producing a BT-R

1

protein that uses one of the BT-R

1

encoding nucleic acid molecules herein described. In general terms, the production of a recombinant BT-R

1

protein typically involves the following steps.

First, a nucleic acid molecule is obtained that encodes a BT-R

1

protein or a fragment thereof, such as the nucleic acid molecule depicted in FIG.

1

. The BT-R

1

encoding nucleic acid molecule is then preferably placed in an operable linkage with suitable control sequences, as described above, to generate an expression unit containing the BT-R

1

encoding sequence. The expression unit is used to transform a suitable host and the transformed host is cultured under conditions that allow the production of the BT-R

1

protein. Optionally the BT-R

1

protein is isolated from the medium or from the cells; recovery and purification of the protein may not be necessary in some instances where some impurities may be tolerated.

Each of the foregoing steps can be done in a variety of ways. For example, the desired coding sequences may be obtained from genomic fragments and used directly in an appropriate host. The construction of expression vectors that are operable in a variety of hosts is accomplished using an appropriate combination of replicons and control sequences. The control sequences, expression vectors, and transformation methods are dependent on the type of host cell used to express the gene and were discussed in detail earlier. Suitable restriction sites can, if not normally available, be added to the ends of the coding sequence so as to provide an excisable gene to insert into these vectors. A skilled artisan can readily adapt any host/expression system known in the art for use with BT-R

1

encoding sequences to produce a BT-R

1

protein.

H. Identification of Agents and Cellular Constituents that Bind to a BT-R

1

Protein

Another embodiment of the present invention provides methods for identifying agents and cellular constituents that bind to BT-R

1

. Specifically, agents and cellular constituents that bind to BT-R

1

can be identified by: 1) the ability of the agent/constituent to bind to BT-R

1

, 2) the ability to block BT-toxin binding to BT-R

1

, and/or 3) the ability to kill BT-R

1

expressing cells. Activity assays for BT-R

1

activity and binding and competitive assays using a BT-R

1

protein are suitable for use in high through-put screening methods, particularly using a soluble fragment of BT-R

1

that contains the BT-toxin binding domain, such as that disclosed in Example 5.

In detail, in one embodiment, BT-R

1

is mixed with an agent or cellular extract. After mixing under conditions that allow association of BT-R

1

with the agent or component of the extract, the mixture is analyzed to determine if the agent/component bound to the BT-R

1

. Binding agents/components are identified as being able to bind to BT-R

1

. Alternatively or consecutively, BT-R

1

activity can be directly assessed as a means for identifying agonists and antagonists of BT-R

1

activity.

Alternatively, targets that are bound by a BT-R

1

protein can be identified using a yeast two-hybrid system or using a binding-capture assay. In the yeast two hybrid system, an expression unit encoding a fusion protein made up of one subunit of a two subunit transcription factor and the BT-R

1

protein is introduced and expressed in a yeast cell. The cell is further modified to contain 1) an expression unit encoding a detectable marker whose expression requires the two subunit transcription factor for expression and 2) an expression unit that encodes a fusion protein made up of the second subunit of the transcription factor and a cloned segment of DNA. If the cloned segment of DNA encodes a protein that binds to the BT-R

1

protein, the expression results in the interaction of the BT-R

1

and the encoded protein. This brings the two subunits of the transcription factor into binding proximity, allowing reconstitution of the transcription factor. This results in the expression of the detectable marker. The yeast two hybrid system is particularly useful in screening a library of cDNA encoding segments for cellular binding partners of BT-R

1

.

The BT-R

1

protein used in the above assays can be: an isolated and fully characterized protein, a fragment of a BT-R

1

protein (such as a soluble fragment containing the BT-toxin binding site), a cell that has been altered to express a BT-R

1

protein/fragment or a fraction of a cell that has been altered to express a BT-R

1

protein/fragment. Further, the BT-R

1

protein can be the entire BT-R

1

protein or a defined fragment of the BT-R

1

protein. It will be apparent to one of ordinary skill in the art that so long as the BT-R

1

protein or fragment can be assayed for agent binding, e.g., by a shift in molecular weight or activity, the present assay can be used.

The method used to identify whether an agent/cellular component binds to a BT-R

1

protein will be based primarily on the nature of the BT-R

1

protein used. For example, a gel retardation assay can be used to determine whether an agent binds to BT-R

1

or a fragment thereof. Alternatively, immunodetection and biochip technologies can be adopted for use with the BT-R

1

protein. A skilled artisan can readily employ numerous art-known techniques for determining whether a particular agent binds to a BT-R

1

protein.

Agents and cellular components can be further, or alternatively, tested for the ability to block the binding of a BT-toxin to a BT-R

1

protein/fragment. Alternatively, antibodies to the BT-toxin binding site or other agents that bind to the BT-toxin binding site on the BT-R

1

protein can be used in place of the BT-toxin.

Agents and cellular components can be further tested for the ability to modulate the activity of a BT-R

1

protein using a cell-free assay system or a cellular assay system. As the activities of the BT-R

1

protein become more defined, functional assays based on the identified activity can be employed.

As used herein, an agent is said to antagonize BT-R

1

activity when the agent reduces BT-R

1

activity. The preferred antagonist will selectively antagonize BT-R

1

, not affecting any other cellular proteins. Further, the preferred antagonist will reduce BT-R

1

activity by more than 50%, more preferably by more than 90%, most preferably eliminating all BT-R

1

activity.

As used herein, an agent is said to agonize BT-R

1

activity when the agent increases BT-R

1

activity. The preferred agonist will selectively agonize BT-R

1

, not affecting any other cellular proteins. Further, the preferred antagonist will increase BT-R

1

activity by more than 50%, more preferably by more than 90%, most preferably more than doubling BT-R

1

activity.

Agents that are assayed in the above method can be randomly selected or rationally selected or designed. As used herein, an agent is said to be randomly selected when the agent is chosen randomly without considering the specific sequences of the BT-R

1

protein or BT-toxin. An example of randomly selected agents is the use of a chemical library or a peptide combinatorial library, or a growth broth of an organism or plant extract.

As used herein, an agent is said to be rationally selected or designed when the agent is chosen on a nonrandom basis that takes into account the sequence of the target site and/or its conformation in connection with the agent's action. Agents can be rationally selected or rationally designed by utilizing the peptide sequences that make up the BT-R

1

protein and BT-toxin. For example, a rationally selected peptide agent can be a peptide whose amino acid sequence is identical to a fragment of a BT-R

1

protein or BT-toxin.

The agents tested in the methods of the present invention can be, as examples, peptides, small molecules, and vitamin derivatives, as well as carbohydrates. A skilled artisan can readily recognize that there is no limit as to the structural nature of the agents used in the present screening method. One class of agents of the present invention are peptide agents whose amino acid sequences are chosen based on the amino acid sequence of the BT-R

1

protein or BT-toxin. Small peptide agents can serve as competitive inhibitors of BT-R

1

protein activity.

Peptide agents can be prepared using standard solid phase (or solution phase) peptide synthesis methods, as is known in the art. In addition, the DNA encoding these peptides may be synthesized using commercially available oligonucleotide synthesis instrumentation and produced recombinantly using standard recombinant production systems. The production using solid phase peptide synthesis is necessitated if non-gene-encoded amino acids are to be included.

Another class of agents of the present invention are antibodies immunoreactive with critical positions of the BT-R

1

protein. As described above, antibodies are obtained by immunization of suitable mammalian subjects with peptides, containing as antigenic regions, those portions of the BT-R

1

protein intended to be targeted by the antibodies. Critical regions particularly include the BT-toxin binding domain identified in Example 5. Such agents can be used in competitive binding studies to identify second generation BT-R

1

binding agents.

The cellular extracts tested in the methods of the present invention can be, as examples, aqueous extracts of cells or tissues, organic extracts of cells or tissues or partially purified cellular fractions. A skilled artisan can readily recognize that there is no limit as to the source of the cellular extract used in the screening method of the present invention. The preferred source for isolating cellular binding partners of BT-R

1

are cells that express BT-R

1

or cells that are in close proximity to BT-R

1

expressing cells.

An outline of one screening method is as follows. Cells are modified by transfection, retroviral infection, electroporation or other known means, to express a BT-R

1

protein and then cultured under conditions wherein the receptor protein is produced and displayed. If desired, the cells are then recovered from the culture for use in the assay, or the culture itself can be used per se.

In the assays, the modified cells are contacted with the candidate toxin and the effect on metabolism or morphology is noted in the presence and absence of the candidate. The effect may be cytotoxic—i.e., the cells may themselves exhibit one of the indices of cell death, such as reduced thymidine uptake, slower increase in optical density of the culture, reduced exclusion of vital dyes (e.g., trypan blue), increased release of viability markers such as chromium and rubidium, and the like. The differential response between the toxin-treated cells and the cells absent the toxin is then noted. The strength of the toxin can be assessed by noting the strength of the response.

These assays may be conducted directly as described above or competitively with known toxins. For example, one approach might be to measure the diminution in binding of labeled BT cry toxin in the presence and absence of the toxin candidate.

In addition to simply screening candidates, the screen can be used to devise improved forms of toxins which are more specific or less specific to particular classes of insects as desired. The ability to determine binding affinity (K

a

and K

d

), dissociation and association rates, and cytotoxic effects of a candidate allows quick, accurate and reproducible screening techniques for a large number of toxins and other ligands under identical conditions which was not possible heretofore. Such information will facilitate the selection of the most effective toxins and ligands for any given receptor obtained from any desired host cell.

Competition assays may also employ antibodies that are specifically immunoreactive with the receptor. Such antibodies can be prepared in the conventional manner by administering the purified receptor to a vertebrate animal, monitoring antibody titers and recovering the antisera or the antibody-producing cells for immortalization, to obtain immortalized cells capable of secreting antibodies of the appropriate specificity. Techniques for obtaining immortalized B cells and for screening them for secretion of the desired antibody are now conventional in the art. The resulting monoclonal antibodies may be more effective than the polyclonal antisera as competition reagents; furthermore, the availability of the immortalized cell line secreting the desired antibody assures uniformity of production of the same reagent over time. The information and the structural characteristics of toxins and ligands tested will permit a rational approach to designing more efficient toxins and ligands. Additionally, such assays will lead to a better understanding of the function and the structure/function relationship of both toxin/ligand and BT-R

1

analogs. In turn, this will allow the development of highly effective toxins/ligands. Ligands include natural and modified toxins, antibodies (anti-receptor and antiidiotypic antibodies which mimic a portion of a toxin that binds to a receptor, and whatever small molecules bind the receptors.

I. Uses of Agents that Bind to a BT-R

1

Protein

As provided in the Background section, BT-R

1

is the target for the insecticidal activity of BT-toxins. Agents that bind a BT-R

1

protein can be used: 1) to kill BT-R

1

expressing cells, 2) to identify agents that block the interaction of a BT-toxin with BT-R

1

and 3) in methods for identifying cells that express BT-R

1

.

The methods employed in using the BT-R

1

binding agents will be based primarily on the nature of the BT-R

1

binding agent and its intended use. For example, a BT-R

1

binding agent can be used to deliver a conjugated toxin to a BT-R

1

expressing cell; modulate BT-R

1

activity; directly kill BT-R

1

expressing cells; or screen for and identify competitive binding agents. An agent that inhibits the activity of BT-R

1

can be used to directly inhibit the growth of BT-R

1

expressing cells. Further, identified cellular factors that bind to BT-R

1

can, themselves, be used in binding/competitive assays to identify agonist and antagonists of BT-R

1

.

J. Methods for Identifying the Presence of a BT-R

1

Protein or Gene

The present invention further provides methods for identifying cells, tissues or organisms expressing a BT-R

1

protein or a BT-R

1

gene. Such methods can be used to diagnose the presence of cells or an organism that expresses a BT-R

1

protein in vivo or in vitro. The methods of the present invention are particularly useful in the determining the presence of cells that are a target for BT-toxin activity or for identifying susceptibility of an organism to a BT-toxin or BT-toxin-like agent. Specifically, the presence of a BT-R

1

protein can be identified by determining whether a BT-R

1

protein, or nucleic acid encoding a BT-R

1

protein, is expressed in a cell, tissue or organism.

A variety of immunological and molecular genetic techniques can be used to determine if a BT-R

1

protein is expressed/produced in a particular cell or sample. In general, an extract containing nucleic acid molecules or an extract containing proteins is prepared. The extract is then assayed to determine whether a BT-R

1

protein, or a BT-R

1

encoding nucleic acid molecule, is produced in the cell.

For example, to perform a diagnostic test based on nucleic acid molecules, a suitable nucleic acid sample is obtained and prepared using conventional techniques. DNA can be prepared, for example, simply by boiling a sample in SDS. The extracted nucleic acid can then be subjected to amplification, for example by using the polymerase chain reaction (PCR) according to standard procedures, such as a RT-PCR method, to selectively amplify a BT-R

1

encoding nucleic acid molecule or fragment thereof. The size or presence of a specific amplified fragment (typically following restriction endonuclease digestion) is then determined using gel electrophoresis or the nucleotide sequence of the fragment is determined (for example, see Weber and May

Am J Hum Genet

(1989) 44:388-339; Davies, J. et al.

Nature

(1994)

371

:

130

-

136

)). The resulting size of the fragment or sequence is then compared to the known BT-R

1

proteins encoding sequences, for example via hybridization probe. Using this method, the presence of a BT-R

1

protein can be identified.

To perform a diagnostic test based on proteins, a suitable protein sample is obtained and prepared using conventional techniques. Protein samples can be prepared, for example, simply by mixing a sample with SDS followed by salt precipitation of a protein fraction. The extracted protein can then be analyzed to determine the presence of a BT-R

1

protein using known methods. For example, the presence of specific sized or charged variants of a protein can be identified using mobility in an electric filed. Alternatively, antibodies can be used for detection purposes. A skilled artisan can readily adapt known protein analytical methods to determine if a sample contains a BT-R

1

protein.

Alternatively, BT-R

1

protein or gene expression can also be used in methods to identify agents that decrease the level of expression of a BT-R

1

gene. For example, cells or tissues expressing a BT-R

1

protein can be contacted with a test agent to determine the effects of the agent on BT-R

1

protein/gene expression. Agents that activate BT-R

1

protein/gene expression can be used as an agonist of BT-R

1

activity whereas agents that decrease BT-R

1

protein/gene expression can be used as an antagonist of BT-R

1

activity.

K. Methods to Sensitize Cells

The present invention further provides methods of sensitizing cells such that they become susceptible to killing with a BT-toxin, or a BT-toxin analog. Specifically, host cells transformed to express BT-R

1

receptor, or a homolog of the BT-R

1

receptor, become sensitive to the mode of action of BT-toxins. The binding of a BT-toxin to a BT-R

1

receptor expressed on the surface of the transformed tells results in induction of a cellular death and apoptosis of the cell expressing the BT-R

1

receptor. Accordingly, the BT-R

1

receptor is an appropriate candidate for use in transforming cells in which it is desirable to induce cell death.

There are numerous situations in which it is desirable to introduce the selected gene into a selected population of cells, thus bringing about cell death. One such example is in the therapeutic treatment of cancer cells. In using specifically targeted vectors for delivery of BT-R

1

-encoding DNA molecules into a tumor cell, tumor cells within a patient can be engineered to express a BT-R

1

protein. Such cells then become susceptible to death upon treatment with a BT-toxin. Since BT-toxin is not normally toxic to mammalian cells, this method is particularly applicable to inducing cell death in particular cells in a mammalian host. Other situations where it may be desirable to stimulate cell death in particular cells or cell lines are in the treatment of autoimmune disorders and in the treatment of cells harboring pathogens, such as malaria or HIV agents.

The choice of the actual steps employed to introduce a BT-R

1

-encoding DNA molecule into a cell to render the cells susceptible to treatment with BT-toxin is based primarily on the cell type that is to be altered, the conditions under which the cell type will be altered, and the overall use envisioned. A skilled artisan can readily adapt art-known methods for use with the BT-R

1

-encoding DNA molecule of the present invention.

L. Animal Models and Gene Therapy

The BT-R

1

gene and the BT-R

1

protein can also serve as a target for generating transgenic organisms in which the pattern of BT-R

1

expression has been altered. For example, in one application, BT-R

1

deficient insects or insect cells can be generated using standard knock-out procedures to inactivate a BT-R

1

gene, or, if such animals are nonviable, inducible BT-R

1

antisense molecules can be used to regulate BT-R

1

activity/expression. Alternatively, cells or an organism can be altered so as to contain a

Manduca sexta

BT-R

1

encoding nucleic acid molecule or an antisense-BT-R

1

expression unit that directs the expression of a BT-R

1

protein or an antisense molecule in a tissue specific fashion. In such uses, an organism or cells, for example insects or insect cells, is generated in which the expression of a BT-R

1

gene is altered by inactivation or activation and/or replaced by a

Manduca sexta

BT-R

1

gene. This can be accomplished using a variety of art-known procedures such as targeted recombination. Once generated, the BT-R

1

expression altered cells or organisms can be used to 1) identify biological and pathological processes mediated by the BT-R

1

protein, 2) identify proteins and other genes that interact with the BT-R

1

protein, 3) identify agents that can be exogenously supplied to overcome a BT-R

1

protein deficiency and 4) serve as an appropriate screen for identifying mutations within the BT-R

1

gene that increases or decreases activity.

For example, it is possible to generate transgenic insects, such as members of the dipteran order, expressing the

Manduca sexta

minigene encoding BT-R

1

in a tissue specific-fashion and test the effect of over-expression of the protein in tissues and cells that normally do not contain the BT-R

1

protein.

M. Use of Expression Control Elements of the BT-R

1

Gene

The present invention further provides the expression control sequences found 5′ of the of the newly identified BT-R

1

gene in a form that can be used in generating expression vectors. Specifically, the BT-R

1

expression control elements, such as the BT-R

1

promoter, that can readily be identified as being 5′ from the ATG start codon in the BT-R

1

gene, can be used to direct the expression of an operably linked protein encoding DNA sequence. Since BT-R

1

expression is mostly tissue-specific, the expression control elements are particularly useful in directing the expression of an introduced transgene in a tissue specific fashion. A skilled artisan can readily use the BT-R

1

gene promoter and other regulatory elements to generate expression vectors using methods known in the art.

Without further description, it is believed that one of ordinary skill in the art can, using the preceding description and the following illustrative examples, make and utilize the compounds of the present invention and practice the claimed methods. The following working examples therefore, specifically point out preferred embodiments of the present invention, and are not to be construed as limiting in any way the remainder of the disclosure.

EXAMPLE 1

Purification and Sequence Determination of BT-R

1

Protein

Midguts of

M. sexta

were extracted and the BT-R

1

protein purified according to the method of Vadlamudi, R. K. et al.

J Biol Chem

(1993) 268:1233, referenced above and incorporated herein by reference. The electroeluted band was confirmed to contain BT-R

1

protein by binding to

125

I-crIAb toxin. In gel electrophoresis, the protein bound to toxin had an apparent weight of approximately 210 kD under reducing and nonreducing conditions.

The purified electroeluted BT-R

1

was subjected to cyanogen bromide digestion and the cyanogen bromide fragments separated on a 17% high-resolution tricine SDS-polyacrylamide gel as described by Schagger, H. et al.

Anal Biochem

(1987) 166:368. The separated fragments were transferred to Problott membranes (Applied Biosystems) and five bands were extracted and subjected to microsequencing using standard instrumentation. The amino acid sequences obtained were:

1. (Met)-Leu-Asp-Tyr-Glu-Val-Pro-Glu-Phe-Gln-Ser-Ile-Thr-Ile-Arg-Val-Val-Ala-Thr-Asp-Asn-Asn-Asp-Thr-Arg-His-Val-Gly-Val-Ala Thr-Asp-Asn-Asn-Asp-Thr-Arg-His-Val-Gly-Val-Ala (SEQ ID NO:3);

2. (Met)-X-Glu-Thr-Tyr-Glu-Leu-Ile-Ile-His-Pro-Phe-Asn-Tyr-Tyr-Ala (SEQ ID NO:4);

3. (Met)-X-X-X-His-Gln-Leu-Pro-Leu-Ala-Gln-Asp-Ile-Lys-Asn-His (SEQ ID NO:5);

4. (Met)-Phe/Pro-Asn/Ile-Val-Arg/Tyr-Val-Asp-Ile/Gly (SEQ ID NO:6);

5. (Met)-Asn-Phe-Phe/His-Ser-Val-Asn-Arg/Asp-Glu (SEQ ID NO:7).

EXAMPLE 2

Recovery of cDNA

An

M. sexta

cDNA library was constructed from midgut tissue in λgt10 using the Superscript Choice System according to the manufacturer's instructions (Life Technologies, Inc.). Degenerate oligonucleotide probes were constructed based on the peptide sequences determined in Example 1 using the methods and approach described in Zhang, S. et al.

Gene

(1991) 105:61. Synthetic oligonucleotides corresponding to peptides 1-3 of Example 1 were labeled with α

32

P using polynucleotide kinase and used as probes as described in the standard cloning manual of Maniatis, T. et al.

Molecular Cloning: A Laboratory Manual

(Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y., 2nd ed. 1989). A clone hybridizing to all three probes identified from 40 positive clones as hybridizing to all three of the probes was plaque-purified from a screen of 4×10

5

recombinants and subcloned into pBluescript (Stratagene). It contained an insert of 5571 bp.

Double-stranded cDNA in pBluescript was sequenced in both directions by the dideoxy termination method with Sequanase (USB) according to the manufacturer's instructions. The sequencing showed an open reading frame of 4584 base pairs or 1528 amino acids along with a polyadenylation signal at position 5561. The sequence obtained and the deduced amino acid sequence is shown in FIG.

1

.

Thus, the deduced protein has a molecular mass of 172 kD and a pl of approximately 4.5. The amino acid sequences of the cyanogen bromide fragments of native receptor match perfectly within the deduced amino acid sequence. The open reading frame begins with an ATG that is flanked by the consensus translation initiation sequence GAGATGG for eucaryotic mRNAs as described by Kozak, M.

Nucleic Acids Res

(1987) 15:8125.

As shown in

FIGS. 2A-2H

, the deduced amino acid sequence includes a putative signal, shown underlined, preceding the mature N-terminus Asn-Glu-Arg-etc. Eleven repeats (cad1-cad11) are shown in the extracellular region upstream of the membrane domain, shown with the heavy underline, at positions 1406-1427 (SEQ ID NO:2). The end of the 11th repeat is shown with an arrowhead. The positions of the five CNBR fragments are also shown under the complete sequence.

FIG. 2I

compares the BT-R

1

sequence obtained herein with other members of the cadherin family. Like known cadherins, the external domain of BT-R

1

is highly repetitive and contains 11 repeats (cad1-cad11; see

FIG. 2

I). The other cadherins compared in

FIG. 2

I are mouse P cadherin (mP EC1);

Drosophila fat

EC18 (fat EC18) and protocadherin (PC42 EC2), and

Manduca sexta

intestinal transporter (HPT-1-EC-1). The eleven repeats of the cadherin motif in BT-R

1

(cad1-cad11) are individually aligned with a single motif sequence from each of the other members of the cadherin family. Conserved residues are boxed. The greatest similarity of BT-R

1

to the cadherins is with the extracellular repeats of the cadherin motif of mouse P-cadherin,

Drosophila fat

tumor suppressor and the protocadherins, although homologies are not high (20-40 homology and 30-60 percent similarity). The conserved repeats of BT-R

1

included AXDXD (SEQ ID NO.12), DXE, DXNDXXP (SEQ ID NO:13), one glutamic acid residue and two glycine residues (

FIG. 2

I). Motifs A/VXDXD (SEQ ID NO:14), DXNDN (SEQ ID NO:15) are the consensus sequences for calcium binding and two such regions are present in a typical cadherin repeat. In all repeats of BT-R

1

, the sequence DXNDN (SEQ ID NO:15) is preceded by 8 to 14 hydrophobic amino acids. Similar hydrophobic sequences also have been observed in the cadherins. The length of the hydrophobic stretches suggests that these areas are not transmembrane regions buy that the represent J-sheet structures commonly present in cadherin-like repeats. BT-R

1

contains a putative cytoplasmic domain of 101 amino acids, smaller than vertebrate cadherin cytoplasmic domains (160 amino acids), and shows no homology to any of the cadherin cytoplasmic domains or to cytoplasmic domains of other proteins to which it has been compared in a current sequence data base.

To confirm that the sequenced clone encoded full-length BT-R

1

protein, total mRNA was prepared from midguts of

M. sexta

subjected to Northern blot by hybridization with the antisense 4.8 kb SacI fragment of the BT-R

1

cDNA clone. The Northern blot analysis was conducted by hybridizing to the antisense probe at 42° C. and 50% formamide, 5× Denhardt's Reagent, 5×SSCP and 50 μg/ml salmon sperm DNA. The filter was then washed two times with 1×SSC+0.1% SDS and two times with 0.15×SSC+0.1% SDS at 42° C. Each wash was roughly 20 minutes. The filter was then exposed to X-ray film for 24 hours. The 4.8 kb probe hybridized to a single 5.6 kb band.

The BT-R

1

clone was translated using rabbit reticulolysate and the resulting translated products were immunoprecipitated with antisera raised against native protein encoded by BT-R

1

. For the in vitro translation, pBluescript plasmid containing BT-R

1

cDNA was linearized and transcribed with T

3

polymerase (Pharmacia). The translation was conducted according to manufacturer's instructions with nuclease-treated rabbit reticulolysate (Life Technologies, Inc.). After one hour of incubation at 30° C., the reaction mixture was combined with an equal volume of SDS buffer or lysed with 50 mM Tris buffer containing 1% NP40 and 250 mM NaCl (pH 8.0) for immunoprecipitation. Preimmune serum was used as a control. Translation and immunoprecipitation products were electrophoresed on a 7.5% SDS-polyacrylamide gel fixed, treated with Enhance (Dupont NEN), dried and exposed to X-ray film for 12 hours.

Two protein bands of approximately 172 kD and 150 kD as determined by SDS-PAGE were obtained; it is postulated that the 150 kD translation product was due to initiation of translation from an internal methionine at amino acid 242. This is consistent with the observations of Kozak,

M. Mol Cell Biol

(1989) 9:5073.

Thus, both results confirm that a full-length clone was obtained.

EXAMPLE 3

Recombinant Production and Characteristics of the BT-R

1

Protein

The BT-R

1

cDNA clone was subcloned into the mammalian expression vector pcDNA3 (Invitrogen) and the construct transfected into COS-7 cells. Membranes isolated from the COS-7 transfectants were solubilized, electrophoresed and ligand blotted with

125

I-CryIAb toxin. The cells were harvested 60 hours after transfection, washed with phosphate-buffered saline and lysed by freezing in liquid nitrogen. Cell membranes were prepared by differential centrifugation as described by Elshourbagy, N. A. et al.

J Biol Chem

(1993) 266:3873. Control cells were COS-7 cells transfected with pcDNA3.

The cell membranes (10 μg) were separated on 7.5% SDS-PAGE blotted to a nylon membrane and blocked with Tris-buffered saline containing 5% nonfat dry milk powder, 5% glycerol and 1% Tween-20. The nylon membrane was then incubated with

125

I-CryIAb toxin (2×10

5

cpm/ml) for two hours with blocking buffer, dried and exposed to X-ray film at −70° C. The labeled toxin bound to a 210±5 kD protein; the 210 kD band was observed only in lanes containing membranes prepared from either

M. sexta

or COS-7 cells transfected with the BT-R

1

cDNA construct containing 4810 bp of cDNA comprising the open reading frame.

The discrepancy between the 210 kD protein expressed and the calculated 172 kD molecular weight is due to glycosylation of the protein; in vitro translation of the cDNA clone, as described above, which does not result in glycosylation, does produce the 172 kD protein. To verify this, the COS-7 produced protein was subjected to digestion with N-glycosidase-F by first denaturing the purified protein by boiling in 1% SDS for 5 minutes followed by addition of NP-40 to a final concentration of 1% in the presence of 0.1% SDS, and then incubating the denatured protein in sodium phosphate buffer, pH 8.5 at 37° C. with N-glycosidase-F for 10 hours. Controls were incubated under the same conditions without enzyme. Digestion products were separated on a 7.5% SDS-PAGE and stained with Coomassie brilliant blue. This glycosidase treatment reduced the molecular weight of BT-R

1

protein from 210 to 190 kD; this indicates N-glycosylation at some of the 16 consensus N-glycosylation sites in the protein. Treatment of BT-R

1

with O-glycosidase and neuraminidase did not alter the mobility of the protein.

In addition, embryonic 293 cells were transfected with the BT-R

1

cDNA clone in pcDNA3 and incubated with the labeled toxin (0.32 nM,) in the presence of increasing concentrations (0 to 10

−6

M) of unlabeled toxin. Nonspecific binding was measured as bound radioactivity in the presence of 1 TM unlabeled toxin. A value for the dissociation constant (K

d

) of 1015 pM was determined by Scatchard analysis; this is approximately the same value that was obtained for the natural receptor as described by Vadlamudi, R. K. et al.

J Biol Chem

(1993) (supra).

EXAMPLE 4

Physiological Effect of BT Toxin on Modified Embryonic 293 Cells

Both unmodified embryonic 293 cells, and 293 cells which have been modified to produce the BT-R

1

receptor as described in Example 3, when cultured in vitro form adherent star-shaped clusters. When BT toxin (200 nM) is added to serum-free medium, the clusters round up and release from the plastic surfaces of the culture dish. This effect is also observed under known conditions of cytotoxicity for 293 cells. The foregoing effect is observed only when the cells are cultured in serum-free medium since the toxin binds to serum and would thus be ineffective under conditions where serum is present.

However, in the presence of anti-receptor antisera, this effect of BT toxin is blocked. Also, when serum is added back to a culture of modified E293 cells which has been treated in serum-free conditions with the toxin, the cells revert to their normal star-shaped adherent cluster shapes. This indicates that the effect of the toxin is reversible.

EXAMPLE 5

Identification of a fragment of BT-R

1

that Binds to a BT Toxin

To understand some of the properties of BT-R

1

, research has been undertaken to define the location of the BT-R

1

/Cry1Ab protein-protein interaction. The full-length wild-type amino acid sequence of BT-R

1

is provided in

FIG. 1

with a block diagram of a possible cadherin-like structure for BT-R

1

shown in FIG.

3

. In both figures, restriction digest sites from the cDNA are provided relative to the positions at which they would disrupt the amino acid coding sequence.

A small fragment lying between the BamHI and SacI restriction sites of wild-type BT-R

1

was cloned into the vector pCITE (Novagen). This vector contains transcription/translation sequences designed for use in a rabbit reticulocyte lysate (RRL) system. The clone has been analyzed by restriction mapping and mRNA expression (FIG.

4

). Lane UP shows the uncut plasmid and lanes NP and XP show restriction digests using NsiI and XhoI, respectively. NsiI is used because it has only one restriction site lying within the Bam-Sac fragment and does not cut anywhere within the pCITE vector. The BSP lane shows the restriction digest of the clone using BamHI and Sacd. The digest releases the cloned fragment which separates at about 700 base pairs. The RT1 and RT2 lanes show mRNA transcription from the clone after linearization with XhoI. The mRNA separates at the expected 1350 base pairs.

Protein for analysis has been prepared from this clone in two ways. First, an RRL translation kit was employed to produce protein from the MRNA transcription reaction described above. Second, the plasmid was added directly to an RRL based transcription and translation (TNT) coupled kit. Protein production was detected using

35

S-methionine as a tag (FIG.

5

). The LCR lane shows production of luciferase protein from mRNA in an RRL kit and the LCT lane is luciferase protein from a plasmid containing the luciferase coding sequence translated in the TNT kit. Both are positive controls to demonstrate that the two translation kits are operational. The major bands for luciferase translation are observed at 66 kDa. The lanes labeled as RR

1

and RR2 show expression of the polypeptide sequence of the Bam-Sac fragment of BT-R

1

translated from RMRNA in the RRL kit. The lanes TT1 and TT2 are translations from the pCITE plasmid containing the Bam-Sac fragment from the TNT kit. All four lanes possess a major band at 30 kDa which is the expected size of the Bam-Sac fragment with the addition of a coded antibody tag called S-tag. S-tag is part of the multicloning site of pCITE.

The clone was then tested for its ability to bind the insecticidal toxin Cry1Ab. Polypeptide translation of the Bam-Sac fragment of BT-R

1

was carried out in duplicate as described above. The only change is that the

35

S-methionine tag was left out of the reaction mixtures to produce non-radiolabeled proteins. The proteins were separated by SDS-PAGE, blotted to nitrocellulose and hybridized with

125

I-labeled Cry1Ab (FIG.

6

). BBMV is wild-type BT-R

1

prepared from the midgut brush border membrane vesicles (RBRMV) of

M. sexta

, and, is used as a positive control. RBK and TBK are RRL and TNT control reactions prepared without mRNA or plasmid present to determine whether proteins endogenous to either kit bind Cry1Ab. R

1

and RR2 are translations from the RRL kit and TT1 and TT2 are from the TNT kit. A single 30-kDa band appears in each of these lanes. Two are marked by arrows. These bands demonstrate that the Bam-Sac fragment of BT-R

1

is capable of binding Cry1Ab insecticidal toxin.

To further understand the nature of this binding site, a set of truncation mutants of BT-R

1

was prepared through the use of restriction digests. The cDNA was digested at specific sites to remove increasingly larger portions of the C-terminus. The restriction enzymes used were NsiI, BamHI, NruI, ClaI, XhoI and StuI (FIGS.

1

and

3

). The procedure involved linearizing the plasmid at each one of these sites and transcribing up to the truncation. The shortened mRNAs then were translated in an RRL kit blotted to nitrocellulose and hybridized with

125

I-labeled Cry1Ab. Translation of the wild-type BT-R

1

from the cDNA showed binding to a 172-kDa protein band, the expected size of wild-type BT-R

1

. It also shows smaller bands that bind Cry1Ab although the nature of these bands has not been determined. A blank made by preparing an RRL reaction mixture without any mRNA gaves several bands below 66 kDa that show some type of binding of Cry1Ab to the reticulocytes. The specificity of this binding has not been determined. The truncation mutants created by NsiI, BamHI, NruI, ClaI, XhoI and StuI restriction digests did not show any binding to Cry1Ab except in the region where the reticulocytes bind Cry1Ab. This data demonstrates that the removal of the last 100 amino acids from wild type BT-R

1

by NsiI restriction results in the loss of the ability of BT-R

1

to bind Cry1Ab. This localizes the toxin binding site on the BT-R

1

clone and provides a soluble fragment of the receptor that can be used in toxin and other binding studies.

A clone of a fragment of BT-R

1

, called the Bam-Sac fragment, has been prepared. It was prepared using BamHI and SacI restriction digests (

FIG. 1

) and cloning of the resulting fragment into a vector called pCITE. The polypeptide sequence was translated and tested for binding to the insecticidal toxin Cry1Ab (FIG.

8

). The Bam-Sac fragment binds to Cry1Ab, providing first insight into the location of the Cry1Ab binding site within the BT-R

1

sequence. It lies in the last 234 C-terminal amino acids. This evidence is further supported by a set of truncation mutants that has been prepared. Removal of the 100 most C-terminal amino acids from wild type BT-R

1

results in the loss of Cry1Ab binding. The C-terminal end of BT-R

1

is the location of the Cry1Ab binding site.

EXAMPLE 6

Identification of Homologue of BT-R

1

that Binds to a BT Toxin

Western blots of tissue extracts prepared from Pink bollworm and European corn borer were prepare and probed with labeled Cry1a (FIG.

7

). The results show that homologues of BT-R

1

are present in these two insects and can be readily isolated using the methods described herein.

15

1

5582

DNA

M. sexta

CDS

(197)...(5348)

1
gaccaatcgg agtgtggtga atttttggaa aatattttgt gcggttcctt tagttgtgta 60
atatagtact ttagttacaa atttggaata atttggcagc aaaaccatct gcagcaacaa 120
aatcatctgc agctgcgaaa tcatctgcag cagcaaaagc atcttcagga gcgagaaaag 180
ccccaaataa tgtgag atg gca gtt gac gtc cga atc gct gcc ttc ctg ctg 232
Met Ala Val Asp Val Arg Ile Ala Ala Phe Leu Leu
1 5 10
gtg ttt ata gcg cct gca gtt tta gct caa gag aga tgt ggg tat atg 280
Val Phe Ile Ala Pro Ala Val Leu Ala Gln Glu Arg Cys Gly Tyr Met
15 20 25
acc gcc atc cca agg cta cca cga ccg gat aat ttg cca gta cta aat 328
Thr Ala Ile Pro Arg Leu Pro Arg Pro Asp Asn Leu Pro Val Leu Asn
30 35 40
ttt gaa ggc cag aca tgg agt cag agg ccc ctg ctc ccc gcc ccg gag 376
Phe Glu Gly Gln Thr Trp Ser Gln Arg Pro Leu Leu Pro Ala Pro Glu
45 50 55 60
cgg gat gac ctg tgc atg gac gcc tac cac gtg ata aca gcc aac ctc 424
Arg Asp Asp Leu Cys Met Asp Ala Tyr His Val Ile Thr Ala Asn Leu
65 70 75
ggc acg cag gtc atc tac atg gat gaa gag ata gaa gac gaa atc acc 472
Gly Thr Gln Val Ile Tyr Met Asp Glu Glu Ile Glu Asp Glu Ile Thr
80 85 90
atc gcc ata ctt aat tat aac gga cca tca act ccg ttc att gaa ctg 520
Ile Ala Ile Leu Asn Tyr Asn Gly Pro Ser Thr Pro Phe Ile Glu Leu
95 100 105
cca ttt tta tcc ggt tcg tac aat ctg ctg atg ccg gtc atc agg aga 568
Pro Phe Leu Ser Gly Ser Tyr Asn Leu Leu Met Pro Val Ile Arg Arg
110 115 120
gtt gac aac ggg gag tgg cat ctc atc atc acg caa aga cag cat tac 616
Val Asp Asn Gly Glu Trp His Leu Ile Ile Thr Gln Arg Gln His Tyr
125 130 135 140
gag ttg ccc ggc atg cag cag tac atg ttc aat gtg cgc gtg gac ggc 664
Glu Leu Pro Gly Met Gln Gln Tyr Met Phe Asn Val Arg Val Asp Gly
145 150 155
cag tcg ctg gtg gca ggc gtg tct ctc gct atc gtc aac ata gat gac 712
Gln Ser Leu Val Ala Gly Val Ser Leu Ala Ile Val Asn Ile Asp Asp
160 165 170
aac gcg ccc atc ata caa aac ttc gag cct tgc cgg gtt cct gaa ctg 760
Asn Ala Pro Ile Ile Gln Asn Phe Glu Pro Cys Arg Val Pro Glu Leu
175 180 185
ggc gag cca ggg ttg aca gaa tgc aca tac caa gta tcg gac gcg gac 808
Gly Glu Pro Gly Leu Thr Glu Cys Thr Tyr Gln Val Ser Asp Ala Asp
190 195 200
gga cgg atc agc aca gag ttc atg acg ttc agg atc gac agc gtt cgt 856
Gly Arg Ile Ser Thr Glu Phe Met Thr Phe Arg Ile Asp Ser Val Arg
205 210 215 220
ggc gac gag gag acc ttc tac atc gaa cgg acg aat atc ccc aac caa 904
Gly Asp Glu Glu Thr Phe Tyr Ile Glu Arg Thr Asn Ile Pro Asn Gln
225 230 235
tgg atg tgg cta aat atg acc ata ggc gtt aat acc tcg ctc aac ttc 952
Trp Met Trp Leu Asn Met Thr Ile Gly Val Asn Thr Ser Leu Asn Phe
240 245 250
gtc acc agt ccg ctg cat ata ttc agc gtg aca gcc ctg gac tcg ctc 1000
Val Thr Ser Pro Leu His Ile Phe Ser Val Thr Ala Leu Asp Ser Leu
255 260 265
ccg aac acc cac acg gtg act atg atg gtg caa gtg gcg aat gtg aac 1048
Pro Asn Thr His Thr Val Thr Met Met Val Gln Val Ala Asn Val Asn
270 275 280
agc cgt ccg ccg cgc tgg ctg gag atc ttc gct gtc caa cag ttt gaa 1096
Ser Arg Pro Pro Arg Trp Leu Glu Ile Phe Ala Val Gln Gln Phe Glu
285 290 295 300
gag aaa tct tac caa aac ttc aca gtg agg gcg atc gac gga gac act 1144
Glu Lys Ser Tyr Gln Asn Phe Thr Val Arg Ala Ile Asp Gly Asp Thr
305 310 315
gag atc aat atg cct atc aac tac agg ctg atc aca aat gag gaa gac 1192
Glu Ile Asn Met Pro Ile Asn Tyr Arg Leu Ile Thr Asn Glu Glu Asp
320 325 330
aca ttc ttc agc att gag gcc ctg cct ggt gga aaa agc ggg gct gta 1240
Thr Phe Phe Ser Ile Glu Ala Leu Pro Gly Gly Lys Ser Gly Ala Val
335 340 345
ttc ctc gtg tcg cca att gac cgc gac aca ctg caa cga gag gtg ttt 1288
Phe Leu Val Ser Pro Ile Asp Arg Asp Thr Leu Gln Arg Glu Val Phe
350 355 360
cca ctt acg atc gtc gct tac aaa tat gat gag gag gcc ttc tcc aca 1336
Pro Leu Thr Ile Val Ala Tyr Lys Tyr Asp Glu Glu Ala Phe Ser Thr
365 370 375 380
tca aca aac gtg gtc atc att gtg aca gac atc aac gac caa aga cct 1384
Ser Thr Asn Val Val Ile Ile Val Thr Asp Ile Asn Asp Gln Arg Pro
385 390 395
gaa cct ata cac aag gaa tat cga ctg gca atc atg gag gag acg ccc 1432
Glu Pro Ile His Lys Glu Tyr Arg Leu Ala Ile Met Glu Glu Thr Pro
400 405 410
ctg acc ctc aac ttc gat aaa gaa ttc gga ttt cat gat aag gat tta 1480
Leu Thr Leu Asn Phe Asp Lys Glu Phe Gly Phe His Asp Lys Asp Leu
415 420 425
ggt caa aac gct cag tac acg gtg cgt cta gag agc gtg gac cct cca 1528
Gly Gln Asn Ala Gln Tyr Thr Val Arg Leu Glu Ser Val Asp Pro Pro
430 435 440
ggc gct gct gag gca ttc tac ata gcg cct gaa gtc ggc tac cag cga 1576
Gly Ala Ala Glu Ala Phe Tyr Ile Ala Pro Glu Val Gly Tyr Gln Arg
445 450 455 460
cag acc ttc atc atg ggc acc ctc aat cac tcc atg ctg gat tac gaa 1624
Gln Thr Phe Ile Met Gly Thr Leu Asn His Ser Met Leu Asp Tyr Glu
465 470 475
gtg cca gag ttt cag agt att acg att cgg gtg gta gcg acc gac aac 1672
Val Pro Glu Phe Gln Ser Ile Thr Ile Arg Val Val Ala Thr Asp Asn
480 485 490
aac gac acg agg cac gtg ggc gtc gcg ttg gtt cac att gac ctc atc 1720
Asn Asp Thr Arg His Val Gly Val Ala Leu Val His Ile Asp Leu Ile
495 500 505
aat tgg aac gat gag cag ccg atc ttc gaa cac gcc gtg cag acc gtc 1768
Asn Trp Asn Asp Glu Gln Pro Ile Phe Glu His Ala Val Gln Thr Val
510 515 520
acc ttc gac gag act gaa ggc gag ggg ttc ttc gtc gcc aag gcg gtt 1816
Thr Phe Asp Glu Thr Glu Gly Glu Gly Phe Phe Val Ala Lys Ala Val
525 530 535 540
gca cac gac aga gac atc ggg gat gtc gtc gag cat act tta ttg ggt 1864
Ala His Asp Arg Asp Ile Gly Asp Val Val Glu His Thr Leu Leu Gly
545 550 555
aac gct gtt aac ttc ctg acc atc gac aaa ctc acc ggc gac atc cgc 1912
Asn Ala Val Asn Phe Leu Thr Ile Asp Lys Leu Thr Gly Asp Ile Arg
560 565 570
gtc tca gct aac gac tcc ttc aac tac cat cga gaa agt gaa tta ttt 1960
Val Ser Ala Asn Asp Ser Phe Asn Tyr His Arg Glu Ser Glu Leu Phe
575 580 585
gtg cag gtg cga gct aca gac acg ctg ggc gaa ccc ttc cac acg gcg 2008
Val Gln Val Arg Ala Thr Asp Thr Leu Gly Glu Pro Phe His Thr Ala
590 595 600
acg tca cag ctg gtc ata cga cta aat gac atc aac aac acg cca ccc 2056
Thr Ser Gln Leu Val Ile Arg Leu Asn Asp Ile Asn Asn Thr Pro Pro
605 610 615 620
acc tta cgg ctg cct cga ggc agt ccc caa gtg gag gag aac gtg cct 2104
Thr Leu Arg Leu Pro Arg Gly Ser Pro Gln Val Glu Glu Asn Val Pro
625 630 635
gat ggc cac gtc atc acc cag gag tta cgc gcc acc gac ccc gac acc 2152
Asp Gly His Val Ile Thr Gln Glu Leu Arg Ala Thr Asp Pro Asp Thr
640 645 650
acg gcc gat ctg cgc ttc gag ata aac tgg gac acc tct ttc gcc acc 2200
Thr Ala Asp Leu Arg Phe Glu Ile Asn Trp Asp Thr Ser Phe Ala Thr
655 660 665
aag caa ggc cgc cag gct aac ccc gac gag ttt agg aat tgc gtg gaa 2248
Lys Gln Gly Arg Gln Ala Asn Pro Asp Glu Phe Arg Asn Cys Val Glu
670 675 680
atc gag acc atc ttc ccc gag att aac aac cgg gga ctg gct atc ggc 2296
Ile Glu Thr Ile Phe Pro Glu Ile Asn Asn Arg Gly Leu Ala Ile Gly
685 690 695 700
cgc gtt gta gcg cgc gaa atc aga cac aac gtg acc ata gac tac gag 2344
Arg Val Val Ala Arg Glu Ile Arg His Asn Val Thr Ile Asp Tyr Glu
705 710 715
gag ttt gag gtc ctc tcc ctc aca gtg agg gtg cgt gac ctt aac acc 2392
Glu Phe Glu Val Leu Ser Leu Thr Val Arg Val Arg Asp Leu Asn Thr
720 725 730
gtc tac gga gac gac tac gac gaa tcg atg ctc aca ata act ata atc 2440
Val Tyr Gly Asp Asp Tyr Asp Glu Ser Met Leu Thr Ile Thr Ile Ile
735 740 745
gat atg aac gac aac gcg ccg gtg tgg gtg gag ggg act ctg gag cag 2488
Asp Met Asn Asp Asn Ala Pro Val Trp Val Glu Gly Thr Leu Glu Gln
750 755 760
aac ttc cga gtc cgc gag atg tcg gcg ggc ggg ctc gtg gtg ggc tcc 2536
Asn Phe Arg Val Arg Glu Met Ser Ala Gly Gly Leu Val Val Gly Ser
765 770 775 780
gtg cgc gcg gac gac atc gac gga ccg ctc tac aac caa gtg cga tac 2584
Val Arg Ala Asp Asp Ile Asp Gly Pro Leu Tyr Asn Gln Val Arg Tyr
785 790 795
acc att ttc cct cgt gaa gac aca gat aag gac ctg ata atg atc gac 2632
Thr Ile Phe Pro Arg Glu Asp Thr Asp Lys Asp Leu Ile Met Ile Asp
800 805 810
ttc ctc acg ggt caa att tcc gtg aac aca agc ggc gcc atc gac gcg 2680
Phe Leu Thr Gly Gln Ile Ser Val Asn Thr Ser Gly Ala Ile Asp Ala
815 820 825
gat act cct cca cgc ttc cac ctc tac tat aca gtg gtc gct agt gac 2728
Asp Thr Pro Pro Arg Phe His Leu Tyr Tyr Thr Val Val Ala Ser Asp
830 835 840
cga tgc tcg aca gaa gat cct gca gat tgc ccc cct gac ccg act tat 2776
Arg Cys Ser Thr Glu Asp Pro Ala Asp Cys Pro Pro Asp Pro Thr Tyr
845 850 855 860
tgg gaa acc gaa gga aat atc aca atc cac atc acc gac acg aac aac 2824
Trp Glu Thr Glu Gly Asn Ile Thr Ile His Ile Thr Asp Thr Asn Asn
865 870 875
aag gtc ccg cag gcg gaa acg act aag ttc gat acc gtc gtg tat att 2872
Lys Val Pro Gln Ala Glu Thr Thr Lys Phe Asp Thr Val Val Tyr Ile
880 885 890
tac gag aac gca acc cac tta gac gag gtg gtc act ctg ata gcc agt 2920
Tyr Glu Asn Ala Thr His Leu Asp Glu Val Val Thr Leu Ile Ala Ser
895 900 905
gat ctt gac aga gac gaa ata tac cac acg gtg agc tac gtc atc aat 2968
Asp Leu Asp Arg Asp Glu Ile Tyr His Thr Val Ser Tyr Val Ile Asn
910 915 920
tat gca gtg aac cct cga ctg atg aac ttc ttc tcc gtg aac cga gag 3016
Tyr Ala Val Asn Pro Arg Leu Met Asn Phe Phe Ser Val Asn Arg Glu
925 930 935 940
acc ggc ctg gtg tac gtg gac tat gag acc cag ggt agt ggc gag gtg 3064
Thr Gly Leu Val Tyr Val Asp Tyr Glu Thr Gln Gly Ser Gly Glu Val
945 950 955
ctg gac cgt gat ggt gat gaa cca acg cac cgt atc ttc ttc aac ctc 3112
Leu Asp Arg Asp Gly Asp Glu Pro Thr His Arg Ile Phe Phe Asn Leu
960 965 970
atc gac aac ttc atg ggg gaa gga gaa ggt aac aga aat cag aac gac 3160
Ile Asp Asn Phe Met Gly Glu Gly Glu Gly Asn Arg Asn Gln Asn Asp
975 980 985
aca gaa gtt ctc gtt atc ttg ttg gat gtg aat gac aat gct cct gaa 3208
Thr Glu Val Leu Val Ile Leu Leu Asp Val Asn Asp Asn Ala Pro Glu
990 995 1000
ttg cca ccg ccg agc gaa ctc tct tgg act ata tct gag aac ctt aag 3256
Leu Pro Pro Pro Ser Glu Leu Ser Trp Thr Ile Ser Glu Asn Leu Lys
1005 1010 1015 1020
cag ggc gtc cgt ctt gaa cca cat atc ttc gcc ccg gac cgc gac gag 3304
Gln Gly Val Arg Leu Glu Pro His Ile Phe Ala Pro Asp Arg Asp Glu
1025 1030 1035
ccc gac aca gac aac tcc agg gtc ggc tac gag atc ctg aac ctc agc 3352
Pro Asp Thr Asp Asn Ser Arg Val Gly Tyr Glu Ile Leu Asn Leu Ser
1040 1045 1050
acg gag cgg gac atc gaa gtg ccg gag ctg ttt gtg atg ata cag atc 3400
Thr Glu Arg Asp Ile Glu Val Pro Glu Leu Phe Val Met Ile Gln Ile
1055 1060 1065
gcg aac gtc acg gga gag ctg gag acc gcc atg gac ctc aag gga tat 3448
Ala Asn Val Thr Gly Glu Leu Glu Thr Ala Met Asp Leu Lys Gly Tyr
1070 1075 1080
tgg ggg acg tac gct ata cat ata cgg gca ttc gac cac ggc att ccg 3496
Trp Gly Thr Tyr Ala Ile His Ile Arg Ala Phe Asp His Gly Ile Pro
1085 1090 1095 1100
caa atg tcc atg aac gag aca tat gag ctg atc atc cat ccg ttc aac 3544
Gln Met Ser Met Asn Glu Thr Tyr Glu Leu Ile Ile His Pro Phe Asn
1105 1110 1115
tac tac gcg cct gag ttc gtc ttc ccg acc aac gat gcc gtc ata cga 3592
Tyr Tyr Ala Pro Glu Phe Val Phe Pro Thr Asn Asp Ala Val Ile Arg
1120 1125 1130
ctt gcg agg gaa cga gct gta atc aat gga gtt cta gcg aca gtg aac 3640
Leu Ala Arg Glu Arg Ala Val Ile Asn Gly Val Leu Ala Thr Val Asn
1135 1140 1145
gga gag ttc ttg gag cgg ata tcg gcg act gat ccg gac gga ctc cac 3688
Gly Glu Phe Leu Glu Arg Ile Ser Ala Thr Asp Pro Asp Gly Leu His
1150 1155 1160
gcg ggc gtc gtc acc ttc caa gtg gta ggc gat gag gaa tca caa cgg 3736
Ala Gly Val Val Thr Phe Gln Val Val Gly Asp Glu Glu Ser Gln Arg
1165 1170 1175 1180
tac ttt caa gta gtt aac gat ggc gag aac ctc ggc tcg ttg agg tta 3784
Tyr Phe Gln Val Val Asn Asp Gly Glu Asn Leu Gly Ser Leu Arg Leu
1185 1190 1195
ctg caa gcc gtt cca gag gag atc agg gag ttc cgg ata acg att cgc 3832
Leu Gln Ala Val Pro Glu Glu Ile Arg Glu Phe Arg Ile Thr Ile Arg
1200 1205 1210
gct aca gac cag gga acg gac cca gga ccg ctg tcc acg gac atg acg 3880
Ala Thr Asp Gln Gly Thr Asp Pro Gly Pro Leu Ser Thr Asp Met Thr
1215 1220 1225
ttc aga gtt gtt ttt gtg ccc acg caa gga gaa cct aga ttc gcg tcc 3928
Phe Arg Val Val Phe Val Pro Thr Gln Gly Glu Pro Arg Phe Ala Ser
1230 1235 1240
tca gaa cat gct gtc gct ttc ata gaa aag agt gcc ggc atg gaa gag 3976
Ser Glu His Ala Val Ala Phe Ile Glu Lys Ser Ala Gly Met Glu Glu
1245 1250 1255 1260
tct cac caa ctt cct cta gca caa gac atc aag aac cat ctc tgt gaa 4024
Ser His Gln Leu Pro Leu Ala Gln Asp Ile Lys Asn His Leu Cys Glu
1265 1270 1275
gac gac tgt cac agc att tac tat cgt att atc gat ggc aac agc gaa 4072
Asp Asp Cys His Ser Ile Tyr Tyr Arg Ile Ile Asp Gly Asn Ser Glu
1280 1285 1290
ggt cat ttc ggc ctg gat cct gtt cgc aac agg ttg ttc ctg aag aaa 4120
Gly His Phe Gly Leu Asp Pro Val Arg Asn Arg Leu Phe Leu Lys Lys
1295 1300 1305
gag ctg ata agg gaa caa agt gcc tcc cac act ctg caa gtg gcg gct 4168
Glu Leu Ile Arg Glu Gln Ser Ala Ser His Thr Leu Gln Val Ala Ala
1310 1315 1320
agt aac tcg ccc gat ggt ggc att cca ctt cct gct tcc atc ctt act 4216
Ser Asn Ser Pro Asp Gly Gly Ile Pro Leu Pro Ala Ser Ile Leu Thr
1325 1330 1335 1340
gtc act gtt acc gtg agg gag gca gac cct cgt cca gtg ttt gtg agg 4264
Val Thr Val Thr Val Arg Glu Ala Asp Pro Arg Pro Val Phe Val Arg
1345 1350 1355
gaa ttg tac acc gca ggg ata tcc aca gcg gac tcc atc ggc aga gag 4312
Glu Leu Tyr Thr Ala Gly Ile Ser Thr Ala Asp Ser Ile Gly Arg Glu
1360 1365 1370
ctg ctc aga tta cat gcg acc cag tct gaa ggc tcg gcc att act tat 4360
Leu Leu Arg Leu His Ala Thr Gln Ser Glu Gly Ser Ala Ile Thr Tyr
1375 1380 1385
gct ata gac tac gat aca atg gta gtg gac ccc agc ctg gag gca gtg 4408
Ala Ile Asp Tyr Asp Thr Met Val Val Asp Pro Ser Leu Glu Ala Val
1390 1395 1400
aga cag tcg gct ttc gta ctg aac gct caa acc gga gtg ctg acg ctt 4456
Arg Gln Ser Ala Phe Val Leu Asn Ala Gln Thr Gly Val Leu Thr Leu
1405 1410 1415 1420
aat atc cag ccc acg gcc acg atg cat gga ctg ttc aaa ttc gaa gtc 4504
Asn Ile Gln Pro Thr Ala Thr Met His Gly Leu Phe Lys Phe Glu Val
1425 1430 1435
aca gct act gac acg gcc ggc gct cag gac cgc acc gac gtc acc gtg 4552
Thr Ala Thr Asp Thr Ala Gly Ala Gln Asp Arg Thr Asp Val Thr Val
1440 1445 1450
tac gtg gta tcc tcg cag aac cgc gtc tac ttc gtg ttc gtc aac acg 4600
Tyr Val Val Ser Ser Gln Asn Arg Val Tyr Phe Val Phe Val Asn Thr
1455 1460 1465
ctg caa cag gtc gaa gac aac aga gac ttt atc gcg gac acc ttc agc 4648
Leu Gln Gln Val Glu Asp Asn Arg Asp Phe Ile Ala Asp Thr Phe Ser
1470 1475 1480
gct ggg ttc aac atg acc tgc aac atc gac caa gtg gtg ccc gct aac 4696
Ala Gly Phe Asn Met Thr Cys Asn Ile Asp Gln Val Val Pro Ala Asn
1485 1490 1495 1500
gac ccc gtc acc ggc gtg gcg ctg gag cac agc acg cag atg cgc ggc 4744
Asp Pro Val Thr Gly Val Ala Leu Glu His Ser Thr Gln Met Arg Gly
1505 1510 1515
cac ttc ata cgg gac aac gta ccc gta ctc gct gat gag ata gaa cag 4792
His Phe Ile Arg Asp Asn Val Pro Val Leu Ala Asp Glu Ile Glu Gln
1520 1525 1530
atc cgt agt gac cta gtc ctc ctg agc tcg ata caa aca acg ctg gcg 4840
Ile Arg Ser Asp Leu Val Leu Leu Ser Ser Ile Gln Thr Thr Leu Ala
1535 1540 1545
gcg cga tcg ctg gtg ttg cag gac ttg ttg acc aac tcc agc ccg gac 4888
Ala Arg Ser Leu Val Leu Gln Asp Leu Leu Thr Asn Ser Ser Pro Asp
1550 1555 1560
tcg gcg cct gac tcg agc ctc acg gtg tac gtg ctg gcc tca ctg tct 4936
Ser Ala Pro Asp Ser Ser Leu Thr Val Tyr Val Leu Ala Ser Leu Ser
1565 1570 1575 1580
gct gtg ctc ggt ttc atg tgc ctt gtg cta ctg ctt acc ttc atc atc 4984
Ala Val Leu Gly Phe Met Cys Leu Val Leu Leu Leu Thr Phe Ile Ile
1585 1590 1595
agg act aga gcg cta aac cga cgg ttg gaa gcc ctg tcg atg acg aag 5032
Arg Thr Arg Ala Leu Asn Arg Arg Leu Glu Ala Leu Ser Met Thr Lys
1600 1605 1610
tac ggc tca ctg gac tct gga ttg aac cgc gcc ggc atc gcc gcc ccc 5080
Tyr Gly Ser Leu Asp Ser Gly Leu Asn Arg Ala Gly Ile Ala Ala Pro
1615 1620 1625
ggc acc aac aaa cac act gtg gaa ggc tcc aac cct atc ttc aat gaa 5128
Gly Thr Asn Lys His Thr Val Glu Gly Ser Asn Pro Ile Phe Asn Glu
1630 1635 1640
gca ata aag acg cca gat tta gat gcc att agc gag ggt tcc aac gac 5176
Ala Ile Lys Thr Pro Asp Leu Asp Ala Ile Ser Glu Gly Ser Asn Asp
1645 1650 1655 1660
tct gat ctg atc ggc atc gaa gat ctt ccg cac ttt ggc aac gtc ttc 5224
Ser Asp Leu Ile Gly Ile Glu Asp Leu Pro His Phe Gly Asn Val Phe
1665 1670 1675
atg gat cct gag gtg aac gaa aag gca aat ggt tat ccc gaa gtc gca 5272
Met Asp Pro Glu Val Asn Glu Lys Ala Asn Gly Tyr Pro Glu Val Ala
1680 1685 1690
aac cac aac aac aac ttc gct ttc aac ccg act ccc ttc tcg cct gag 5320
Asn His Asn Asn Asn Phe Ala Phe Asn Pro Thr Pro Phe Ser Pro Glu
1695 1700 1705
ttc gtt aac gga cag ttc aga aag atc t agaagataac aacactagtt 5368
Phe Val Asn Gly Gln Phe Arg Lys Ile
1710 1715
aagatcatta attttggagt ttggaattaa gatttttgaa aggatagttg tgataagcct 5428
gtgattttta aaactgtaat tgaaaaaaaa aattgagacc tccatttaag ctcttgctct 5488
catctcatca aattttataa aatgccatta gtcattaaga tactcgattt aatttaagat 5548
tatttaagat attatgtaaa ataaatatat tgtc 5582

2

1717

PRT

M. sexta

2
Met Ala Val Asp Val Arg Ile Ala Ala Phe Leu Leu Val Phe Ile Ala
1 5 10 15
Pro Ala Val Leu Ala Gln Glu Arg Cys Gly Tyr Met Thr Ala Ile Pro
20 25 30
Arg Leu Pro Arg Pro Asp Asn Leu Pro Val Leu Asn Phe Glu Gly Gln
35 40 45
Thr Trp Ser Gln Arg Pro Leu Leu Pro Ala Pro Glu Arg Asp Asp Leu
50 55 60
Cys Met Asp Ala Tyr His Val Ile Thr Ala Asn Leu Gly Thr Gln Val
65 70 75 80
Ile Tyr Met Asp Glu Glu Ile Glu Asp Glu Ile Thr Ile Ala Ile Leu
85 90 95
Asn Tyr Asn Gly Pro Ser Thr Pro Phe Ile Glu Leu Pro Phe Leu Ser
100 105 110
Gly Ser Tyr Asn Leu Leu Met Pro Val Ile Arg Arg Val Asp Asn Gly
115 120 125
Glu Trp His Leu Ile Ile Thr Gln Arg Gln His Tyr Glu Leu Pro Gly
130 135 140
Met Gln Gln Tyr Met Phe Asn Val Arg Val Asp Gly Gln Ser Leu Val
145 150 155 160
Ala Gly Val Ser Leu Ala Ile Val Asn Ile Asp Asp Asn Ala Pro Ile
165 170 175
Ile Gln Asn Phe Glu Pro Cys Arg Val Pro Glu Leu Gly Glu Pro Gly
180 185 190
Leu Thr Glu Cys Thr Tyr Gln Val Ser Asp Ala Asp Gly Arg Ile Ser
195 200 205
Thr Glu Phe Met Thr Phe Arg Ile Asp Ser Val Arg Gly Asp Glu Glu
210 215 220
Thr Phe Tyr Ile Glu Arg Thr Asn Ile Pro Asn Gln Trp Met Trp Leu
225 230 235 240
Asn Met Thr Ile Gly Val Asn Thr Ser Leu Asn Phe Val Thr Ser Pro
245 250 255
Leu His Ile Phe Ser Val Thr Ala Leu Asp Ser Leu Pro Asn Thr His
260 265 270
Thr Val Thr Met Met Val Gln Val Ala Asn Val Asn Ser Arg Pro Pro
275 280 285
Arg Trp Leu Glu Ile Phe Ala Val Gln Gln Phe Glu Glu Lys Ser Tyr
290 295 300
Gln Asn Phe Thr Val Arg Ala Ile Asp Gly Asp Thr Glu Ile Asn Met
305 310 315 320
Pro Ile Asn Tyr Arg Leu Ile Thr Asn Glu Glu Asp Thr Phe Phe Ser
325 330 335
Ile Glu Ala Leu Pro Gly Gly Lys Ser Gly Ala Val Phe Leu Val Ser
340 345 350
Pro Ile Asp Arg Asp Thr Leu Gln Arg Glu Val Phe Pro Leu Thr Ile
355 360 365
Val Ala Tyr Lys Tyr Asp Glu Glu Ala Phe Ser Thr Ser Thr Asn Val
370 375 380
Val Ile Ile Val Thr Asp Ile Asn Asp Gln Arg Pro Glu Pro Ile His
385 390 395 400
Lys Glu Tyr Arg Leu Ala Ile Met Glu Glu Thr Pro Leu Thr Leu Asn
405 410 415
Phe Asp Lys Glu Phe Gly Phe His Asp Lys Asp Leu Gly Gln Asn Ala
420 425 430
Gln Tyr Thr Val Arg Leu Glu Ser Val Asp Pro Pro Gly Ala Ala Glu
435 440 445
Ala Phe Tyr Ile Ala Pro Glu Val Gly Tyr Gln Arg Gln Thr Phe Ile
450 455 460
Met Gly Thr Leu Asn His Ser Met Leu Asp Tyr Glu Val Pro Glu Phe
465 470 475 480
Gln Ser Ile Thr Ile Arg Val Val Ala Thr Asp Asn Asn Asp Thr Arg
485 490 495
His Val Gly Val Ala Leu Val His Ile Asp Leu Ile Asn Trp Asn Asp
500 505 510
Glu Gln Pro Ile Phe Glu His Ala Val Gln Thr Val Thr Phe Asp Glu
515 520 525
Thr Glu Gly Glu Gly Phe Phe Val Ala Lys Ala Val Ala His Asp Arg
530 535 540
Asp Ile Gly Asp Val Val Glu His Thr Leu Leu Gly Asn Ala Val Asn
545 550 555 560
Phe Leu Thr Ile Asp Lys Leu Thr Gly Asp Ile Arg Val Ser Ala Asn
565 570 575
Asp Ser Phe Asn Tyr His Arg Glu Ser Glu Leu Phe Val Gln Val Arg
580 585 590
Ala Thr Asp Thr Leu Gly Glu Pro Phe His Thr Ala Thr Ser Gln Leu
595 600 605
Val Ile Arg Leu Asn Asp Ile Asn Asn Thr Pro Pro Thr Leu Arg Leu
610 615 620
Pro Arg Gly Ser Pro Gln Val Glu Glu Asn Val Pro Asp Gly His Val
625 630 635 640
Ile Thr Gln Glu Leu Arg Ala Thr Asp Pro Asp Thr Thr Ala Asp Leu
645 650 655
Arg Phe Glu Ile Asn Trp Asp Thr Ser Phe Ala Thr Lys Gln Gly Arg
660 665 670
Gln Ala Asn Pro Asp Glu Phe Arg Asn Cys Val Glu Ile Glu Thr Ile
675 680 685
Phe Pro Glu Ile Asn Asn Arg Gly Leu Ala Ile Gly Arg Val Val Ala
690 695 700
Arg Glu Ile Arg His Asn Val Thr Ile Asp Tyr Glu Glu Phe Glu Val
705 710 715 720
Leu Ser Leu Thr Val Arg Val Arg Asp Leu Asn Thr Val Tyr Gly Asp
725 730 735
Asp Tyr Asp Glu Ser Met Leu Thr Ile Thr Ile Ile Asp Met Asn Asp
740 745 750
Asn Ala Pro Val Trp Val Glu Gly Thr Leu Glu Gln Asn Phe Arg Val
755 760 765
Arg Glu Met Ser Ala Gly Gly Leu Val Val Gly Ser Val Arg Ala Asp
770 775 780
Asp Ile Asp Gly Pro Leu Tyr Asn Gln Val Arg Tyr Thr Ile Phe Pro
785 790 795 800
Arg Glu Asp Thr Asp Lys Asp Leu Ile Met Ile Asp Phe Leu Thr Gly
805 810 815
Gln Ile Ser Val Asn Thr Ser Gly Ala Ile Asp Ala Asp Thr Pro Pro
820 825 830
Arg Phe His Leu Tyr Tyr Thr Val Val Ala Ser Asp Arg Cys Ser Thr
835 840 845
Glu Asp Pro Ala Asp Cys Pro Pro Asp Pro Thr Tyr Trp Glu Thr Glu
850 855 860
Gly Asn Ile Thr Ile His Ile Thr Asp Thr Asn Asn Lys Val Pro Gln
865 870 875 880
Ala Glu Thr Thr Lys Phe Asp Thr Val Val Tyr Ile Tyr Glu Asn Ala
885 890 895
Thr His Leu Asp Glu Val Val Thr Leu Ile Ala Ser Asp Leu Asp Arg
900 905 910
Asp Glu Ile Tyr His Thr Val Ser Tyr Val Ile Asn Tyr Ala Val Asn
915 920 925
Pro Arg Leu Met Asn Phe Phe Ser Val Asn Arg Glu Thr Gly Leu Val
930 935 940
Tyr Val Asp Tyr Glu Thr Gln Gly Ser Gly Glu Val Leu Asp Arg Asp
945 950 955 960
Gly Asp Glu Pro Thr His Arg Ile Phe Phe Asn Leu Ile Asp Asn Phe
965 970 975
Met Gly Glu Gly Glu Gly Asn Arg Asn Gln Asn Asp Thr Glu Val Leu
980 985 990
Val Ile Leu Leu Asp Val Asn Asp Asn Ala Pro Glu Leu Pro Pro Pro
995 1000 1005
Ser Glu Leu Ser Trp Thr Ile Ser Glu Asn Leu Lys Gln Gly Val Arg
1010 1015 1020
Leu Glu Pro His Ile Phe Ala Pro Asp Arg Asp Glu Pro Asp Thr Asp
1025 1030 1035 1040
Asn Ser Arg Val Gly Tyr Glu Ile Leu Asn Leu Ser Thr Glu Arg Asp
1045 1050 1055
Ile Glu Val Pro Glu Leu Phe Val Met Ile Gln Ile Ala Asn Val Thr
1060 1065 1070
Gly Glu Leu Glu Thr Ala Met Asp Leu Lys Gly Tyr Trp Gly Thr Tyr
1075 1080 1085
Ala Ile His Ile Arg Ala Phe Asp His Gly Ile Pro Gln Met Ser Met
1090 1095 1100
Asn Glu Thr Tyr Glu Leu Ile Ile His Pro Phe Asn Tyr Tyr Ala Pro
1105 1110 1115 1120
Glu Phe Val Phe Pro Thr Asn Asp Ala Val Ile Arg Leu Ala Arg Glu
1125 1130 1135
Arg Ala Val Ile Asn Gly Val Leu Ala Thr Val Asn Gly Glu Phe Leu
1140 1145 1150
Glu Arg Ile Ser Ala Thr Asp Pro Asp Gly Leu His Ala Gly Val Val
1155 1160 1165
Thr Phe Gln Val Val Gly Asp Glu Glu Ser Gln Arg Tyr Phe Gln Val
1170 1175 1180
Val Asn Asp Gly Glu Asn Leu Gly Ser Leu Arg Leu Leu Gln Ala Val
1185 1190 1195 1200
Pro Glu Glu Ile Arg Glu Phe Arg Ile Thr Ile Arg Ala Thr Asp Gln
1205 1210 1215
Gly Thr Asp Pro Gly Pro Leu Ser Thr Asp Met Thr Phe Arg Val Val
1220 1225 1230
Phe Val Pro Thr Gln Gly Glu Pro Arg Phe Ala Ser Ser Glu His Ala
1235 1240 1245
Val Ala Phe Ile Glu Lys Ser Ala Gly Met Glu Glu Ser His Gln Leu
1250 1255 1260
Pro Leu Ala Gln Asp Ile Lys Asn His Leu Cys Glu Asp Asp Cys His
1265 1270 1275 1280
Ser Ile Tyr Tyr Arg Ile Ile Asp Gly Asn Ser Glu Gly His Phe Gly
1285 1290 1295
Leu Asp Pro Val Arg Asn Arg Leu Phe Leu Lys Lys Glu Leu Ile Arg
1300 1305 1310
Glu Gln Ser Ala Ser His Thr Leu Gln Val Ala Ala Ser Asn Ser Pro
1315 1320 1325
Asp Gly Gly Ile Pro Leu Pro Ala Ser Ile Leu Thr Val Thr Val Thr
1330 1335 1340
Val Arg Glu Ala Asp Pro Arg Pro Val Phe Val Arg Glu Leu Tyr Thr
1345 1350 1355 1360
Ala Gly Ile Ser Thr Ala Asp Ser Ile Gly Arg Glu Leu Leu Arg Leu
1365 1370 1375
His Ala Thr Gln Ser Glu Gly Ser Ala Ile Thr Tyr Ala Ile Asp Tyr
1380 1385 1390
Asp Thr Met Val Val Asp Pro Ser Leu Glu Ala Val Arg Gln Ser Ala
1395 1400 1405
Phe Val Leu Asn Ala Gln Thr Gly Val Leu Thr Leu Asn Ile Gln Pro
1410 1415 1420
Thr Ala Thr Met His Gly Leu Phe Lys Phe Glu Val Thr Ala Thr Asp
1425 1430 1435 1440
Thr Ala Gly Ala Gln Asp Arg Thr Asp Val Thr Val Tyr Val Val Ser
1445 1450 1455
Ser Gln Asn Arg Val Tyr Phe Val Phe Val Asn Thr Leu Gln Gln Val
1460 1465 1470
Glu Asp Asn Arg Asp Phe Ile Ala Asp Thr Phe Ser Ala Gly Phe Asn
1475 1480 1485
Met Thr Cys Asn Ile Asp Gln Val Val Pro Ala Asn Asp Pro Val Thr
1490 1495 1500
Gly Val Ala Leu Glu His Ser Thr Gln Met Arg Gly His Phe Ile Arg
1505 1510 1515 1520
Asp Asn Val Pro Val Leu Ala Asp Glu Ile Glu Gln Ile Arg Ser Asp
1525 1530 1535
Leu Val Leu Leu Ser Ser Ile Gln Thr Thr Leu Ala Ala Arg Ser Leu
1540 1545 1550
Val Leu Gln Asp Leu Leu Thr Asn Ser Ser Pro Asp Ser Ala Pro Asp
1555 1560 1565
Ser Ser Leu Thr Val Tyr Val Leu Ala Ser Leu Ser Ala Val Leu Gly
1570 1575 1580
Phe Met Cys Leu Val Leu Leu Leu Thr Phe Ile Ile Arg Thr Arg Ala
1585 1590 1595 1600
Leu Asn Arg Arg Leu Glu Ala Leu Ser Met Thr Lys Tyr Gly Ser Leu
1605 1610 1615
Asp Ser Gly Leu Asn Arg Ala Gly Ile Ala Ala Pro Gly Thr Asn Lys
1620 1625 1630
His Thr Val Glu Gly Ser Asn Pro Ile Phe Asn Glu Ala Ile Lys Thr
1635 1640 1645
Pro Asp Leu Asp Ala Ile Ser Glu Gly Ser Asn Asp Ser Asp Leu Ile
1650 1655 1660
Gly Ile Glu Asp Leu Pro His Phe Gly Asn Val Phe Met Asp Pro Glu
1665 1670 1675 1680
Val Asn Glu Lys Ala Asn Gly Tyr Pro Glu Val Ala Asn His Asn Asn
1685 1690 1695
Asn Phe Ala Phe Asn Pro Thr Pro Phe Ser Pro Glu Phe Val Asn Gly
1700 1705 1710
Gln Phe Arg Lys Ile
1715

3

30

PRT

M. sexta

3
Met Leu Asp Tyr Glu Val Pro Glu Phe Gln Ser Ile Thr Ile Arg Val
1 5 10 15
Val Ala Thr Asp Asn Asn Asp Thr Arg His Val Gly Val Ala
20 25 30

4

16

PRT

M. sexta

VARIANT

(1)...(16)

Xaa = Any Amino Acid

4
Met Xaa Glu Thr Tyr Glu Leu Ile Ile His Pro Phe Asn Tyr Tyr Ala
1 5 10 15

5

16

PRT

M. sexta

VARIANT

(1)...(16)

Xaa = Any Amino Acid

5
Met Xaa Xaa Xaa His Gln Leu Pro Leu Ala Gln Asp Ile Lys Asn His
1 5 10 15

6

8

PRT

M. sexta

VARIANT

(1)...(8)

Xaa = Any Amino Acid

6
Met Xaa Xaa Val Xaa Val Asp Xaa
1 5

7

9

PRT

M. sexta

VARIANT

(1)...(9)

Xaa = Any Amino Acid

7
Met Asn Phe Xaa Ser Val Asn Xaa Glu
1 5

8

109

PRT

Mouse

8
Glu Trp Val Met Pro Pro Ile Phe Val Pro Glu Asn Gly Lys Gly Pro
1 5 10 15
Phe Pro Gln Arg Leu Asn Gln Leu Lys Ser Asn Lys Asp Arg Gly Thr
20 25 30
Lys Ile Phe Tyr Tyr Ser Ile Thr Gly Pro Gly Ala Asp Ser Pro Pro
35 40 45
Glu Gly Val Phe Thr Ile Glu Lys Glu Ser Gly Trp Leu Leu Leu His
50 55 60
Met Pro Leu Asp Arg Glu Lys Ile Val Lys Tyr Glu Leu Tyr Gly His
65 70 75 80
Ala Val Ser Glu Asn Gly Ala Ser Val Glu Glu Pro Met Asn Ile Ser
85 90 95
Ile Ile Val Thr Asp Gln Asn Asp Asn Lys Pro Lys Phe
100 105

9

105

PRT

Drosophila

9
Glu Asp Thr Val Tyr Ser Phe Asp Ile Asp Glu Asn Ala Gln Arg Gly
1 5 10 15
Tyr Gln Val Gly Gln Ile Val Ala Arg Asp Ala Asp Leu Gly Gln Asn
20 25 30
Ala Gln Leu Ser Tyr Gly Val Val Ser Asp Trp Ala Asn Asp Val Phe
35 40 45
Ser Leu Asn Pro Gln Thr Gly Met Leu Thr Leu Thr Ala Arg Leu Asp
50 55 60
Tyr Glu Glu Val Gln His Tyr Ile Leu Ile Val Gln Ala Gln Asp Asn
65 70 75 80
Gly Gln Pro Ser Leu Ser Thr Thr Ile Thr Val Tyr Cys Asn Val Leu
85 90 95
Asp Leu Asn Asp Asn Ala Pro Ile Phe
100 105

10

92

PRT

Protocadherin

10
Ala Ser Pro Val Ile Thr Leu Ala Ile Pro Glu Asn Thr Asn Gly Ser
1 5 10 15
Leu Phe Pro Ile Pro Leu Ala Ser Asp Arg Asp Ala Asn Glu Leu Gln
20 25 30
Val Ala Glu Asp Gln Glu Glu Lys Gln Pro Gln Leu Ile Val Met Gly
35 40 45
Asn Leu Asp Arg Glu Arg Trp Asp Ser Tyr Asp Leu Thr Ile Lys Val
50 55 60
Gln Asp Gly Gly Ser Pro Pro Arg Ala Thr Ser Ala Leu Leu Arg Val
65 70 75 80
Thr Val Leu Asp Thr Asn Asp Asn Ala Pro Lys Phe
85 90

11

106

PRT

M. sexta

11
Ile Val Thr Glu Asn Ile Trp Lys Ala Pro Lys Pro Val Glu Met Val
1 5 10 15
Glu Asn Ser Thr Pro His Pro Ile Lys Ile Thr Gln Val Arg Trp Asn
20 25 30
Asp Pro Gly Ala Gln Tyr Ser Leu Val Asp Lys Glu Lys Leu Pro Arg
35 40 45
Phe Pro Phe Ser Ile Asp Gln Glu Gly Asp Ile Tyr Val Thr Gln Pro
50 55 60
Ile Asp Arg Glu Glu Lys Asp Ala Tyr Val Phe Tyr Ala Val Ala Lys
65 70 75 80
Asp Glu Tyr Gly Lys Pro Leu Ser Tyr Pro Leu Glu Ile His Val Lys
85 90 95
Val Lys Asp Asn Asp Asn Pro Pro Thr Cys
100 105

12

5

PRT

M. sexta

VARIANT

(1)...(5)

Xaa = Any Amino Acid

12
Ala Xaa Asp Xaa Asp
1 5

13

7

PRT

M. sexta

VARIANT

(1)...(7)

Xaa = Any Amino Acid

13
Asp Xaa Asn Asp Xaa Xaa Pro
1 5

14

5

PRT

M. sexta

VARIANT

(1)...(5)

Xaa = Any Amino Acid

14
Xaa Xaa Asp Xaa Asp
1 5

15

5

PRT

M. sexta

VARIANT

(1)...(5)

Xaa = Any Amino Acid

15
Asp Xaa Asn Asp Asn
1 5

Number	Name	Date	Kind
4675285	Kobayashi	Jun 1987	A
5071654	English	Dec 1991	A
5665595	Petell et al.	Sep 1997	A
5804393	Geiser et al.	Sep 1998	A

Number	Date	Country
0 526 397	Feb 1993	EP
0 526 397	Jan 1996	EP
WO 96 12964	May 1996	WO

	Number	Date	Country
Parent	08/326117	Oct 1994	US
Child	08/880042		US

Antibodies that specifically bind a Bacillus thuringiensis toxin receptor

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

RELATED APPLICATIONS

ACKNOWLEDGEMENT OF GOVERNMENT SUPPORT

US Referenced Citations (4)

Foreign Referenced Citations (3)

Non-Patent Literature Citations (19)

Continuation in Parts (1)

Entry
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R. A. Lerner, Antibodies of predetermined specificity in biology and medicine, Adv. Immunol. 36: 1-44, 1984.*
Almond et al., Suppression of Protein Structure Destabilizing Mutations in Bacillus thuringiensis γ-endotoxin by Second Site Mutations; Biochemistry 32:1040-1046 (1993).
Chen et al., Site-directed mutations in a highly conserved region of Bacillus thuringiensis γ-endotoxin affect inhibition of short circuit current across Bombyx mori midguts, Proc. Natl. Acad. Sci. USA 90:9041-9045 (1993).
Dorsch, J. A. et al., “Determination of the specific region of BT-R1 to which the CryaAb toxin of Bacillus thuringiensis subsp. Berliner binds”, FASEB JOURNAL (ABSTRACTS), vol. 11, No. 9, Jul. 31, 1997, p. A1050.
English, L., Mode of action of delta-endotoxins from Bacillus Thuringiensis: A comparison with othe bacterial toxins, Insect Biochem. Molec. Biol. 22(1):1-7.
Gill et al., The Mode of Action of Bacillus Thuringiensis Endotoxins; Ammu. Rev. Entomol. (1992) 37:615-36.
Hoffman et al., Specificity of Bacillus Thuringiensis γ-endotoxins is Correlated with the Presence of High-affinity Binding Sites in the Brush Border Membrane of Target Insect Midguts; Proc. Natl. Acad. Sci., USA (1988) 85:7844-7848.
Hofte et al., Insecticidal Crystal Proteins of Bacillus Thuringiensis; Microbiological Reviews (1989) 53(2):242-255.
Ishihara et al., Molecular cloning and expression of a cDNA encoding the secretin receptor, EMOB J., vol. 10, No. 7, 1635-1641.
Knight et al., The eceptor for Bacillus thuringiensis CrylA(c) delta-endotoxin in the brush border membrance of the lepidopteran Manduca sexta is aminopeptidase N, Molecular Microbiology (1994) 11(3):429-436 (1994).
Knowles et al., The crystal γ-endotoxins of Bacillus thuringiensis: Models for their mechanism of action on the insect gut, BioEssays 15(7):469-476 (1993).
Lee et al., Location of a Bombyx mori Receptor Binding Region on a Bacillus thuringiensis γ-Endotoxin, J. Biol. Chem., vol. 167, No. 5, pp. 3115-3121 (1992).
Sanchis et al., Identification and partial purification of a Bacillus thuringiensis CryIC γ-endotoxin binding protein from Spodoptera littoralis gut membrances, FEBS 316(3):264-268 (1993).
Sangadala et al., A Mixture of Manduca Sectra Aminopeptidase and Phosphatase Enhances Bacillus Thuringiensis Insecticidal CrylA(c) Toxin Binding and Rb+-K+ Efflux in vitro, vol. 269, No. 13, pp. 10088-10092 (1994).
Vadlamudi et al., Cloning and Expression of a Receptor for an nsecticidal Toxin of Bacillus thuringiensis, J. Biol. Chem. 270(10):5490-5494 (1995).
Vadlamudi et al., A Specific Binding Protein from Manduca Sexta for the Insecticidal Toxin of Bacillus Thuringiensis Subsp., Berliner; J. Biol. Chem. 268(17):12334-12340 (1993).
Van Rie et al., Specificity of Bacillus Thuringiensis γ-endotoxins; Eur. J. Biochem. (1989) 186:239-247.
Van Rie et al., Receptors on the Brush Border Membrane of the Insect Midgut as Determinants of the Specificity of Bacillus Thuringiensis Belta-Endotoxins (1990) 56(5):1378-1385.