NSF Award
2311952
Biological age does not always correlate with chronological age, and it is unclear how physiology contributes to aging or protects from it. Some hypotheses predict that organisms will repair tissues necessary for reproduction, while allowing other tissues to age. Other hypotheses predict the opposite: tissues related to reproduction will age faster because of selection for early life fitness. This research will examine aging dynamics across life stages and tissues, and in response to stress. Bees are an ideal system to probe the mechanistic underpinnings of extreme differences in lifespan, yielding general insight into regulators of aging. Bee life-cycles are short compared to vertebrates and its possible to examine lifetime patterns of senescence. And, many aspects of cellular senescence are conserved across insects and vertebrates. Investigating how aging dynamics differ among species may lead to new ways of disrupting negative effects of aging. Understanding aging is particularly pressing in a world in which organisms are increasingly exposed to stress and many bee species are in decline. The proposed research will support the training of six graduate students and six undergraduate students. A K-12 learning module on bumble bee spring emergence will be developed as a hands-on lesson to engage Native American high school students in STEM. As part of an ongoing collaboration, informational exhibits and outreach events about pollinators will be developed with the Red River Valley Zoo (Fargo, ND) and Science Kids and Wyoming PBS (Laramie, WY). <br/><br/>The objective of the proposed research is to integrate physiology with life history theory to mechanistically explain patterns of aging. Insect metamorphosis may be an extreme version of the disposable soma hypothesis. During metamorphosis, larval tissues are recycled and replaced by imaginal cells with stem cell-like properties, which have the potential to be cellularly “younger” than the tissues they replace. Insect metamorphosis may provide an opportunity to dispose of damaged somatic tissues, mitigating the effects of juvenile exposure to stress. Insect overwintering, also known as diapause, also has important implications for aging. Diapause increases lifespans by six times compared to non-diapausing individuals. This research will determine how metamorphosis and diapause contribute to aging dynamics by examining cellular damage and organismal performance by: 1) determining the relationship between senescence and cellular markers of aging, 2) examining how the disposable soma during metamorphosis influences aging by comparing cellular aging in tissues formed during metamorphosis to those carried over from the larval stage, and 3) assessing whether overwintering dormancy is a slowing down of aging or is regenerative. The proposed research will investigate these dynamics in solitary bees and bumble bees, and will strengthen an already productive collaboration between NDSU, UW, and the USDA-ARS, and greatly extend what is known about the mechanisms that contribute to variation in senescence.<br/><br/>This project is jointly funded by the Integrative Ecological Physiology program and the Established Program to Stimulate Competitive Research (EPSCoR).<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
