Function of Osa in the Differentiation of Drosophila Ovary Germline Stem Cell

doi:10.13560/j.cnki.biotech.bull.1985.2017-0289

Abstract

Abstract:

The Drosophila ovary germline stem cell（GSC）is recognized as an ideal model system for studying stem cell fate regulation in vivo. The epigenetic mechanism is involved in the Drosophila ovary GSC fate regulation. Identification and characterization of apparent epigenetic regulators involved in this process will contribute to reveal underlying regulatory mechanisms. The aim of this study is to investigate the possible functions and the molecular mechanisms of Osa,the chromatin remodeling complex BAP-specific subunit,in Drosophila GSC differentiation. GAL4/UAS binary system combined with RNAi technology was used to specifically down-regulate osa expression in escort cells（ECs）,and immune fluorescent dyeing was for detecting the relevant indexes. The results showed that knock-down of osa led to a significant increase of undifferentiated germ cells（UGCs）in the germarium of ovarian tissue,the positive cells of pMad and Dad-lacZ,two BMP signaling activity reporters,increased significantly. Moreover,EC morphology was abnormal,and they failed to wrap germline cells. In conclusion,Osa might be involved in the regulation of GSC differentiation by BMP signaling pathway-depending and specific morphological process of ECs.

Key words: Drosophila, germline stem, GSC, differentiation

LI Min,QU Jie,LI Meng-jie,HU Xiao-long. Function of Osa in the Differentiation of Drosophila Ovary Germline Stem Cell[J]. Biotechnology Bulletin, 2017, 33(9): 139-144.

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