Chromatin and gene expression changes during female Drosophila germline stem cell development illuminate the biology of highly potent stem cells

• Published in: eLife Vol. 12
• Main Authors: Pang, Liang-Yu, DeLuca, Steven, Zhu, Haolong, Urban, John M, Spradling, Allan C
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 13.10.2023; eLife Sciences Publications, Ltd
• Subjects: Animals; Biology; Cell cycle; Cell differentiation; Cell Differentiation - genetics; Chromatin; Chromatin - metabolism; Cysts; Developmental Biology; Drosophila; Drosophila - genetics; Drosophila melanogaster - metabolism; Drosophila Proteins - metabolism; Embryos; evolution; Females; Follicles; Gene Expression; germ cell; Germ cells; Germ Cells - metabolism; Gluconeogenesis; Insects; Male; Metabolism; Myc protein; Nurse cells; oocyte; Oocytes; Oogonial Stem Cells - metabolism; Ovaries; Polycomb group proteins; Polycomb repression; Ribonucleic acid; RNA; stem cell; Stem cells; Stem Cells - metabolism; transposable element; Zygotes; oocyte; stem cell; developmental biology; transposable element; Polycomb repression; evolution; D. melanogaster; germ cell
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/eLife.90509

Highly potent animal stem cells either self renew or launch complex differentiation programs, using mechanisms that are only partly understood. female germline stem cells (GSCs) perpetuate without change over evolutionary time and generate cystoblast daughters that develop into nurse cells and oocytes. Cystoblasts initiate differentiation by generating a transient syncytial state, the germline cyst, and by increasing pericentromeric H3K9me3 modification, actions likely to suppress transposable element activity. Relatively open GSC chromatin is further restricted by Polycomb repression of testis or somatic cell-expressed genes briefly active in early female germ cells. Subsequently, Neijre/CBP and Myc help upregulate growth and reprogram GSC metabolism by altering mitochondrial transmembrane transport, gluconeogenesis, and other processes. In all these respects GSC differentiation resembles development of the totipotent zygote. We propose that the totipotent stem cell state was shaped by the need to resist transposon activity over evolutionary timescales.