Physiological and Molecular Mechanisms of Stress Tolerance in a Polar InsectEntry ID: NSF-ANT03-37656
Abstract: Polar terrestrial environments are often described as deserts, where water availability is recognized as one of the most important limits on the distribution of terrestrial organisms. Global warming has further impacted the extreme thermal and hydric conditions experienced by Antarctic terrestrial plant and arthropod communities, especially as a result of glacial retreat along the Antarctic ... Peninsula. Within this context we focused our attention on thermal and hydric adaptations in the terrestrial midge, Belgica antarctica, the largest and most southerly holometabolous insect living in this challenging and changing environment. Overwintering midge larvae encased in the frozen substrate must endure desert-like conditions for more than 300 days since free water is biologically unavailable as ice. During the summer, depending on the vagaries of precipitation, wind, temperature and insolation, larvae may be immersed in melt water or detrital outwash from penguin rookeries and seal wallows, in addition to saltwater splash. During the past four years we made considerable progress in defining microclimatic conditions experienced by the larvae, and characterized larval and adult responses to thermal, hydric and osmotic stress at molecular levels. We demonstrated that larvae maintain constitutively elevated levels of heat shock proteins and have the capacity to undergo cryoprotective dehydration, the first demonstration in a true insect. We also discovered a novel role for the rapid cold-hardening response by showing that it increases freezing tolerance in larvae of B. antarctica. Using genomic and proteomic approaches we identified more than 90 genes that are uniquely expressed in response to dehydration, making it one of the best-known polar organisms from a molecular perspective.
Start Date: 2004-01-01Stop Date: 2006-03-25
AGRICULTURE > AGRICULTURAL PLANT SCIENCE
BIOLOGICAL CLASSIFICATION > ANIMALS/INVERTEBRATES > ARTHROPODS > HEXAPODS > INSECTS
BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > SURVIVAL RATES
BIOSPHERE > ECOLOGICAL DYNAMICS > ECOSYSTEM FUNCTIONS > CONSUMPTION RATES
BIOSPHERE > ECOLOGICAL DYNAMICS > ECOSYSTEM FUNCTIONS > RESPIRATION RATE
ISO Topic Category
Email: denlinger.1 at osu.edu
Department of Entomology, 470 Aronoff, 318 W. 12th Ave
Province or State: OH
Postal Code: 43210
Country: United States
Email: leere at muohio.edu
Department of Zoology Miami University
Province or State: Ohio
Postal Code: 45056
Country: United States
Research Publications (undergraduate authors indicated by * and graduate students in bold)
Primary research and review articles (published or accepted for publication)
1. Benoit, J. B., G. Lopez-Martinez, M. A. Elnitsky, R. E. Lee and D. L. Denlinger. 2007a. Moist habitats are essential for adults of the Antarctic midge, Belgica antarctica (Diptera: Chironomidae), to avoid dehydration. European Journal of Entomology 104: 9-14.
2. Benoit, J. B., G. Lopez-Martinez, M. R. Michaud, M. A. ... Elnitsky, R. E. Lee and D. L. Denlinger. 2007b. Mechanisms to reduce dehydration stress in the Antarctic midge, Belgica antarctica. Journal of Insect Physiology 5: 656-667.
3. Benoit, J. B., J. A. Yoder, G. Lopez-Martinez, M. A. Elnitsky, R. E. Lee, and D. L. Denlinger. 2007. Habitat requirements of the seabird tick, Ixodes uriae (Acari: Ixodidae), from the Antarctic Peninsula in relation to water balance characteristics of eggs, nonfed and engorged stages. Journal of Comparative Physiology B 177: 205-215.
4. Benoit, J. B., J. A. Yoder, G. Lopez-Martinez, M. A. Elnitsky, R. E. Lee and D. L. Denlinger, 2008. Adaptations for the maintenance of water balance by three species of Antarctic mites. Polar Biology (in press)
5. Denlinger, D. L. and R. E. Lee. 2008. A midge that lives in Antarctica. In: Insect Adaptations to Environmental Adversity, S. Tanaka (ed.), Kanagawa: Tokai University Press. (in press)
6. Elnitsky, M. A., S. A. L. Hayward, J. B. Benoit, G. Lopez-Martinez, D. L. Denlinger and R. E. Lee. 2008. Cryoprotective dehydration and inoculative freezing in the Antarctic midge, Belgica antarctica. Journal of Experimental Biology 211: 524-530.
7. Elnitsky, M.A. and R.E. Lee. 2008. The rapid cold hardening response in insects: ecological significance and physiological mechanisms. In: Gusta, L., Wisniewski, M. and Tanino, K. (Eds.) Proceedings of the 8th Plant Cold Hardiness Seminar (in press)
8. Lopez-Martinez, G., M. A. Elnitsky, J. B. Benoit, R.E. Lee and D.L. Denlinger. 2008. High resistance to oxidative damage in the Antarctic midge Belgica antarctica and developmentally-linked expression of genes encoding superoxide dismutase, catalase and heat shock proteins. Insect Biochemistry and Molecular Biology (in press)
9. Hayward, S. A. L., J. P. Rinehart, L. H. Sandro, R. E. Lee and D. L. Denlinger. 2007. Slow dehydration promotes desiccation and freeze tolerance in the Antarctic midge, Belgica antarctica. Journal of Experimental Biology 210: 836-844.
10. Lee, R. E. and D. L. Denlinger. 2006. Entomology on the Antarctic Peninsula: The southernmost insect. American Entomologist 52: 84-89.
11. Lee, R. E., M. A. Elnitsky, J. P. Rinehart, S. A. L. Hayward, L. H. Sandro and D. L. Denlinger. 2006. Rapid cold-hardening increases the freezing tolerance of the Antarctic midge, Belgica antarctica. Journal of Experimental Biology 209: 399-406.
12. Michaud, M. R., J. B. Benoit, G. Lopez-Martinez, M. A. Elnitsky, R. E. Lee and D. L. Denlinger. 2008. Metabolomics reveals unique and shared changes in response to heat shock, freezing, and desiccation in the Antarctic midge, Belgica antarctica. Journal of Insect Physiology 54: 645-655.
13. Rinehart, J. P., S. A. L. Hayward, M. A. Elnitsky, L. H. Sandro, R. E. Lee and D. L. Denlinger. 2006. Continuous upregulation of heat shock proteins in larvae, but not adults, of a polar insect. Proceedings of the National Academy of Sciences, USA 103: 14223-14227.
14. Schulte, G. G., M. A. Elnitsky, J. B. Benoit, D. L. Denlinger and R. E. Lee. 2008. Extremely large aggregations of collembolan eggs on Humble Island, Antarctica: A response to early seasonal warming? Polar Biology (in press)
15. Teets, N. M.*, M. A. Elnitsky, J. B. Benoit, G. Lopez-Martinez, D. L. Denlinger and R. E. Lee. 2008. Rapid cold-hardening in larvae of the Antarctic midge, Belgica antarctica: Cellular cold-sensing and a role for calcium. American Journal of Physiology (in press)
Outreach publications in peer-reviewed teaching journals
1. Bugg, S. R., J. Constible, M. Kaput and R. E. Lee. 2007. They're m-e-e-elting! An investigation of glacial retreat in Antarctica. Science Scope 30: 42-28.
2. Constible, J. M. and R. E. Lee. 2006. Awesome aggregations. The Science Teacher 73: 44-50.
3. Constible, J. M., R. G. McWilliams, E. G. Soldo, B. E. Perry, and R. E. Lee. 2007. ... An immersion professional development program in environmental science for inservice elementary school teachers. Journal of Geoscience Education 54: 70-77.
4. Constible, J. M., L. H. Sandro and R. E. Lee. 2007. A cooperative classroom investigation of climate change on the Antarctic Peninsula. The Science Teacher 74: 56-63.
5. Constible, J. M., L. H. Sandro and R. E. Lee. 2008. Ah-CHOO! Increased risk of pollen allergies in the Northern Hemisphere. Journal of College Science Teaching 37: 82-89.
6. Constible, J. M., L. H. Sandro and R. E. Lee. 2008. Carrion - it's what's for dinner: wolves reduce the impact of climate change in Yellowstone National Park. Amer. Biology Teacher 70: 95-102.
7. Sandro, L. H., J. M. Constible and R. E. Lee. 2007. Extreme arthropods: exploring evolutionary adaptations to polar and temperate deserts. Science Scope 30: 25-32.
8. Sandro, L. H. and R. E. Lee. 2006. Winter biology and freeze tolerance in the goldenrod gall fly. American Biology Teacher 68: 29-35.
Creation and Review Dates
DIF Creation Date: 2008-06-06
Last DIF Revision Date: 2008-07-01