| Description |
Steroid hormones are important for many complex physiological processes. One arthropod steroid hormone, ecdysone, was discovered in 1963 to play essential roles in larval development. However, it was not until 40 years later that ecdysone was discovered to be involved in adult physiology as well. In the adult intestines, ecdysone upregulates proliferation and differentiation of intestinal cells, as demonstrated by Dr. Sara Ahmed's experiments with Drosophila melanogaster in Dr. Edgar's lab. This upregulation occurs specifically in mated females, suggesting a remodeling of the tissue to enhance nutrients uptake and/or utilization for egg production. The present study explored how ecdysone affects DNA content and gut growth through new microscopy, nucleus identification, nucleus isolation, and flow cytometry protocols. This study found that mating induced ecdysone increases cause DNA endocycling in enterocytes throughout the Drosophila midgut. The hormone also causes regional effects on intestinal stem cell proliferative activity, increasing proliferation only in the posterior region. Ecdysone receptor loss within the stem cells prevents all ecdysone induced proliferation and differentiation but increases endocycling in enterocytes. |
