School of Science Division of Life Science 43 Genetic Studies on Stem Cell Regulation Supervisor: XIE Ting / LIFS Co-supervisor: TU Renjun / LIFS Student: TANG Xiaohan / SSCI Course: UROP1100, Summer In the Drosophila ovary, germline stem cells (GSCs) continuously proliferate and differentiate to enable constant egg generation. GSC self-renewal and differentiation are maintained by a variety of intrinsic and niche signals in the germarium. As one of the critical signaling pathways in animal cells, the cAMP/Pka pathway is involved in the regulation of many important growth and development processes. However, the functions of cAMP/PKA pathway in controlling GSC development remain unclear. In this study, by knocking down Drosophila cAMP/Pka pathway components in germline and the niche, respectively, we discovered that the lack of cAMP generation in both somatic cells and germline cells leads to defective GSC development. We found that, Pka-R2 knockdown completely loss GSC and its progeny, indicating cAMP/PKA pathway may involve in maintaining GSC. Interestingly, knockdown of rut, the cyclase that is responsible for synthesis of cAMP, in the niche cell also disrupts GSC development. In the future study, we will systematically analyze all cAMP/PKA components in the niche and germline to further verify our findings, and investigate the molecular mechanisms that how cAMP/PKA pathway controls germline development.