Abstract
In many metazoan tissues, highly specialized cells are constantly lost and need to be replaced by tissue homeostasis from adult stem cells. When adult stem cells divide by mitosis their daughter cells either become new stem cells, or enter a proliferation and differentiation path. Recent studies in Drosophila males showed that germline stem cells (GSCs) can increase their mitotic activity in response to repeated mating. Here, we show that the GSC daughters of mated males also had significantly increased mitotic indices (MI) compared to their non-mated control siblings. Just as we previously showed for the GSCs, the increase in MI of the GSC daughters was eliminated when activity of one of the G-proteins, G-gamma, was reduced from the germline cells. This suggests that the mitotic activity of both cell populations is regulated by the same molecular mechanism. However, it is currently not known how G-protein signaling affects the MI. Based on the current knowledge and implications of G-protein signaling, we discuss possible ways how it could modulate germline divisions in Drosophila.
Keywords
Mating, Stem cells, Transit amplifying divisions, Mitotic index