Preliminary Study Of Gene Chm And Gene Taf1 In The Development Of Drosophila Ovary Germline Stem Cell

Adult stem cells have the ability of self-renewing and differentiating to different kinds of cells.It's important for us to study the regulation of adult stem cells' fates in order to clarify the function of adult stem cells and make them into application.Drosophila ovary germline stem cell(GSC)and its nich are suitable for this study in vivo.The regulation of the GSC fate involves the GSC formation,the GSC maintenance and the GSC differentiation.As an important way in the regulation of the organism development,the role of epigenetic mechanisms in the regulation of the GSC fate needs to be studied deeply.In this article,we find Chm(Chameau),a Drosophila histone acetyltransferase and Taf1,a protein related to histone acetyltransference control the GSC fate.(1)The mutation of chm or knockdown of chm in the nich cells causes a GSC formation defect in the Drosophila ovary.This means Chm is required non-autonomously for the GSC formation.In addition,taf1 mutants have defects in the GSC formation too.Either knockdown of taf1 in the germline or in the nich has the same defect,so taf1 can affect the GSC formation in the cell-autonomous and non-autonomous levels.Our further studies show the mechanisms of these two proteins in the regulation of the GSC formation are independent on the regulation of the PGC proliferation or differentiation.(2)The mutation of chm or knockdown of chm in the nich cells affects the maintenance of GSCs,thus chm is non-autonomously needed for the GSC maintenance.And taf1 mutants also lead to a GSC maintenance defect.Further studies show these two proteins may affect the GSC maintenance by regulating cap cells' fates.(3)We also find knockdown of taf1 in the germline inhibits the differentiation of germ cells,but the activation of BMP signaling isn't affected.Further studies show the expression patterns of Bam and Nanos which plays important roles in the differentiation of the germline are changed.This indicates taf1 might affect the differentiation of the germline via a pathway dependent on Bam and Nanos.In summary,Chm and Taf1 which are related to epigenetic regulation play roles in the fate of GSCs.Our work has found some new evidence about epigenetic regulation in the development of GSCs in Drosophila ovaries and provides a new platform for this kind of studies,may help to illuminate the mechanisms of the adult stem cell regulation.