Sex, Stress, and Oxygen Deprivation: Gender-Specific Phenotypes Modulate

Survival in Anoxia Michelle LeBlanc

University of North TexasRonald 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

Ronald E. McNair Program

Dr. Pamela PadillaAlexander Mendenhall and Desh

Mohan, project collaboratorsThe rest of the Padilla lab

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