Transient transcriptional silencing alters the cell cycle to promote germline stem cell differentiation in Drosophila

Developmental biology

SiuWah Wong-Deyrup^1¹  Sean Schowalter^1,2²  Pooja Flora^1³  Matthew DeGennaro^3⁴ 

[1] Biomolecular Sciences Institute, Department of Biological Sciences, Florida International University, Miami, FL 33199, USA^3;Boston University School of Medicine, 815 Albany Street, MA 02119, USA^2;Department of Biological Sciences/The RNA Institute, University at Albany SUNY, Albany, NY 12222, USA^1;University of Massachusetts Medical School, Worcester, MA 01605, USA^4

关键词: Transcriptional silencing;    Cell cycle;    Differentiation;    Germ line;    Stem cells;    Heterochromatin;   

DOI  :  10.1016/j.ydbio.2017.11.014

学科分类：生物科学（综合）

来源: Academic Press

【 摘 要 】

Transcriptional silencing is a conserved process used by embryonic germ cells to repress somatic fate and maintain totipotency and immortality. In Drosophila, this transcriptional silencing is mediated by polar granule component (pgc). Here, we show that in the adult ovary, pgc is required for timely germline stem cell (GSC) differentiation. Pgc is expressed transiently in the immediate GSC daughter (pre-cystoblast), where it mediates a pulse of transcriptional silencing. This transcriptional silencing mediated by pgc indirectly promotes the accumulation of Cyclin B (CycB) and cell cycle progression into late-G2 phase, when the differentiation factor bag of marbles (bam) is expressed. Pgc mediated accumulation of CycB is also required for heterochromatin deposition, which protects the germ line genome against selfish DNA elements. Our results suggest that transient transcriptional silencing in the pre-cystoblast “re-programs” it away from self-renewal and toward the gamete differentiation program.

【 授权许可】

CC BY