We uncovered in developing ovaries, a previously unrecognized developmental microenvironment of oocyte production from the germline stem cells (GSCs) to the primordial follicle (in-preparation). In contrast to mammals, in zebrafish, GSCs are maintained in ovaries and actively produce oocytes throughout life. However, the regulation of zebrafish GSC maintenance, how they produce oocyte lineages, their cellular dynamics, potential progenitor and subpopulations, as well as their niche, are completely unknown. Our current description of GSC dynamics and sub-populations (in-preparation), as well as combined cell biological and spatial genomics approaches, ambitiously aim to decipher the regulation of GSC maintenance and their production of oocytes.
Strikingly, a very similar developmental organization exist in human fetal ovaries, suggesting conserved GSC dynamics and developmental regulation, and we are currently working with our collaborates to address those questions in human fetal ovaries. This emphasizes the zebrafish juvenile ovary as an excellent model for human fetal ovarian development and GSC biology. Our findings hold great potential to identify the missing factors for GSC maintenance in humans, paving the way for future female regenerative medicine.
