ZFIN ID: ZDB-PUB-210317-5
Zebrafish dazl regulates cystogenesis and germline stem cell specification during the primordial germ cell to germline stem cell transition
Bertho, S., Clapp, M., Banisch, T.U., Bandemer, J., Raz, E., Marlow, F.L.
Date: 2021
Source: Development (Cambridge, England)   148(7): (Journal)
Registered Authors: Bandemer, Jan, Banisch, Torsten, Marlow, Florence, Raz, Erez
Keywords: Dazl, Fertility, Germline cyst, Germline stem cells, Incomplete cytokinesis, Ring canals
MeSH Terms:
  • Animals
  • Cytokinesis/physiology
  • Female
  • Fertility/genetics
  • Fertility/physiology
  • Gene Knockout Techniques
  • Germ Cells/growth & development*
  • Germ Cells/metabolism*
  • Male
  • Mutagenesis
  • RNA-Binding Proteins/genetics*
  • RNA-Binding Proteins/metabolism*
  • Stem Cells/metabolism
  • Zebrafish/embryology
  • Zebrafish/genetics*
  • Zebrafish/metabolism*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
PubMed: 33722898 Full text @ Development
Fertility and gamete reserves are maintained by asymmetric divisions of the germline stem cells to produce new stem cells or daughters that differentiate as gametes. Before entering meiosis, differentiating germ cells (GCs) of sexual animals typically undergo cystogenesis. This evolutionary conserved process involves synchronous and incomplete mitotic divisions of a GC daughter (cystoblast) to generate sister cells connected by intercellular bridges that facilitate exchange of materials to support rapid expansion of the gamete progenitor population. Here, we investigated cystogenesis in zebrafish and found that early GCs are connected by ring canals, and show that Deleted in azoospermia (Dazl), a conserved vertebrate RNA-binding protein (Rbp), as a regulator of this process. Analysis of dazl mutants revealed Dazl's essential role in regulating incomplete cytokinesis, germline cyst formation, and germline stem cell specification before the meiotic transition. Accordingly, dazl mutant GCs form defective ring canals, and ultimately remain as individual cells that fail to differentiate as meiocytes. In addition to promoting cystoblast divisions and meiotic entry, dazl is required for germline stem cell establishment and fertility.