The question how adult stem cells maintain themselves and how they produce specialized cells to replenish tissues is fairly well understood for several model tissues. However, how the activity of stem cells is regulated within the adult is only poorly understood. Specifically, whether stem cells can increase the production of specialized cells in situations of demand has not been addressed in any model organism yet.
In male fruitflies, each germline stem cell division ultimately leads to the development of exactly 64 mature gametes. Preliminary studies show that demand for more gametes, induced by mating experiments, leads to a response: an increase in the frequency at which male germ line stem cells divide. The investigator plans to use genetic and molecular techniques for identifying the communication pathway regulating the response. It is expected that the studies reveal which tissues are involved in the communication, which biochemical molecules mediate the communication, and which target genes are activated within the germ line stem cells in reponse to demand. The outcome of the proposed research will have broad impacts on our understanding how environmental events utilize biochemical pathways to feed back on stem cells and thereby on the vitality and activity of specific tissues in the adult body.
The proposed research has a strong teaching and outreach component. Fruitflies are an excellent model organims widely used in research and education. Graduate students, undergraduate students, high school students, and K-12 teachers participating in the proposed research will be trained both intellectually and technically. The investigator has trained many female and minority students and intends to continue recruiting students from programs supporting students from underrepresented groups.
