Somatic steroid hormone signaling promotes early oocyte polarization in Drosophila

In the ovary, oogenesis depends on intercellular communication between somatic and germ cell populations for proper oocyte production. Steroid hormone signaling, well-described for its diverse roles throughout oogenesis, contributes to soma-germline communication using cholesterol-derived steroids as ligands to activate or repress transcription in target cells containing the appropriate receptors. To date, research shows defects in cysts development, germline stem cell (GSC) maintenance and somatic escort cell projections when somatic to germline communication is disrupted, yet none display a direct impact on oocyte production. Our findings suggests that the steroid hormone receptor, Ecdysone Receptor (EcR), is required in the escort cells for timely cyst maturation and oocyte polarization and provides insight into the molecular mechanisms responsible for this process