The Bric- à-Brac BTB/POZ transcription factors are necessary in niche cells for germline stem cells establishment and homeostasis through control of BMP/DPP signaling in the < i > Drosophila melanogaster < /i > ovary

by Laurine Miscopein Saler, Virginie Hauser, Mathieu Bartoletti, Charlotte Mallart, Marianne Malartre, Laura Lebrun, Anne-Marie Pret, Laurent Th éodore, Fabienne Chalvet, Sophie Netter Many studies have focused on the mechanisms of stem cell maintenancevia their interaction with a particular niche or microenvironment in adult tissues, but how formation of a functional niche is initiated, including how stem cells within a niche are established, is less well understood. AdultDrosophila melanogaster ovary Germline Stem Cell (GSC) niches are comprised of somatic cells forming a stack called a Terminal Filament (TF) and associated Cap and Escort Cells (CCs and ECs, respectively), which are in direct contact with GSCs. In the adult ovary, the transcription factor Engrailed is specifically expressed in niche cells where it directly controls expression of thedecapentaplegic (dpp) gene encoding a member of the Bone Morphogenetic Protein (BMP) family of secreted signaling molecules, which are key factors for GSC maintenance. In larval ovaries, in response to BMP signaling from newly formed niches, adjacent primordial germ cells become GSCs. Thebric- à-brac paralogs (bab1 andbab2) encode BTB/POZ domain-containing transcription factors that are expressed in developing niches of larval ovaries. We show here that their functions are necessary specifically within precursor cells for TF formation during these stages. We also identify a new function for Bab1 and Bab2 within developing nich...
Source: PLoS Genetics - Category: Genetics & Stem Cells Authors: Source Type: research