461V Poster Online - Virtual Posters
Wednesday April 06, 4:00 PM - 7:00 PM

Authors:
Ana Caroline Gandara; Daniela Drummond-Barbosa

Affiliation: Johns Hopkins University, School of Public Health, Baltimore, MD

Keywords:
b. oogenesis; b. germline stem cell

Reproduction of all organisms is shaped by their external environments. As climate change alters the abundance and distribution of many types of organisms around the globe, investigating how temperature impacts the reproduction of organisms has become a major area for scientific investigation. Insects are cold-blooded animals and therefore particularly sensitive to environmental temperatures. Oogenesis is highly sensitive to a variety of environmental and physiological factors; however, it remains largely unknown how exposure of Drosophila melanogaster adult females to chronic thermal stress affects oogenesis. To directly address this question, we incubated newly-eclosed y w adult flies (raised at room temperature, 23°C) at 18°C (cold), 25°C (optimal), or 29°C (warm) for 20 days at constant humidity (>70%) and found that the rate of egg production was reduced in females at both warm and cold temperatures, albeit through distinct cellular mechanisms. Chronic exposure of females to 18°C improved the maintenance of germline stem cells, survival of early germline cysts, and hatching rates but reduced the rate of follicle growth with no obvious effect on vitellogenesis. By contrast, in females at 29°C, germline stem cell numbers and follicle growth were comparable to those in females at 25°C, while early germline cyst death and degeneration of follicles were markedly increased, and hatching rates plummeted over time. Finally, we uncovered a novel role for the warm temperature receptor TrpA1 in mediating the effects of 29°C on oocyte quality. These findings are widely relevant not only to cold-blooded organisms, which exhibit limited thermoregulation, but also potentially to warm-blooded organisms, which are subject to hypothermia, heatstroke, and fever.