Sex, Stress, and Oxygen Deprivation: Gender-Specific Phenotypes Modulate Survival in Anoxia Michelle LeBlanc University of North Texas Ronald E. McNair Program

Oxygen Deprivation What is Anoxia? –<.001 kilopascal of oxygen in environment –Health Issues Stroke Ischemia Center of cancerous tumors –Environmental Deficits Oceanic dead zones

Suspended Animation Reversible state of dormancy –initiated due to environmental stress Mammals –Hibernation –Estivation We can study SA with the model organism Caenorhabditis elegans!!

Caenorhabditis elegans Image adapted from Wormbook

Image Adapted from Wormbook

Hypothesis An modification in gonad function will modulate survival of long-term oxygen deprivation. –Sterile animals may survive anoxia differently than wild-type animals. –Sex may modulate survival in anoxia.

Experimental Schematic

RNAi of sterile-reported genes

Gender in Anoxia

Male Genotype vs Phenotype

Females in anoxia

Oocyte flux and survival

Future Aims What underlies the fog-2(q71) phenotype? –Sperm signaling –Signaling from fertilized embryo Does oocyte flux affect survival? –spe-12(hc76) and fer-15(hc15) Animals that cannot produce spermatids

Acknowledgements

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