Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Sarah Wong - University of Southern California
Co-Author(s): Christina Sisliyan, University of Southern California, Los Angeles, CA; Laura Corrales-Diaz Pomatto, University of Southern California, Los Angeles, CA; John Tower, University of Southern California, Los Angeles, CA; Kelvin J. A. Davies, University of Southern California, Los Angeles, CA
Adaptive homeostasis, in the context of oxidative stress, maintains that organisms experience constant, non-damaging oxidant adaptive signals within a flexible range. Upregulation of stress-responsive genes is sex- and oxidant-dependent, with previous work demonstrating a female-specific adaptation to hydrogen peroxide (H2O2) in fruit flies We have recently generated ‘psuedo-female’ fruit flies, modulated by a whole-body overexpression of the transformer female-specific transcript (“traf”). The character of the ‘psuedo-female’ fruit flies is two-fold: phenotypically female, while maintaining male chromosomes and adaptive to H2O2 pretreatment. Our current work seeks to determine if the oxidative stress response is tissue-specific or systemic. To examine this question, individual tissues in male fruit flies were feminimized: the gut, the nervous system, fat bodies, and oenocytes. Feminized male gut was previously shown by Regan and colleagues (2016) to confer increased lifespan under conditions of caloric restriction, a phenomena typically unique to females. To measure adaptation by changes in survival, male flies with specific feminized tissue were first pretreated with low, signaling doses (µM) of H2O2 before undergoing toxic, but sublethal concentrations (M) of the oxidant. These flies were contrasted with the controls which did not receive pretreatment. We did not find a tissue-specific adaptive response to H2O2 in the chromosomally-male, feminized tissued females. This suggests that adaptation requires a systemic interaction involving the feminization of multiple tissues to induce a female-specific response. We believe this work offers insight into sex-specific adaptation conserved in higher organisms.wongsarah_ern 2017 abstract.docx
Funder Acknowledgement(s): This work was supported by an NIH/NIEHS R01 grant ES03598-25 (PI: Davies, K.J.A.), and by grant #ES003598 from the National Institute of Environmental Health Sciences of the US National Institutes of Health to KJAD.
Faculty Advisor: Kelvin J. A. Davies, email@example.com
Role: Project investigates feminizing tissues of chromosomally-male flies, so I worked on preparing the flies for pretreatment (uM hydrogen peroxide, followed by M hydrogen peroxide) and challenge treatments (M hydrogen peroxide). Survival was determined by adaptation curves for the pretreatment flies, and kill curves for the challenge samples (collected every eight hours for both procedures). Virgin female flies were collected by the undergraduate team to serve as controls.