ALIX and ESCRT-III coordinately control cytokinetic abscission during germline stem cell division in vivo

PLoS Genet. 2015 Jan 30;11(1):e1004904. doi: 10.1371/journal.pgen.1004904. eCollection 2015 Jan.

Abstract

Abscission is the final step of cytokinesis that involves the cleavage of the intercellular bridge connecting the two daughter cells. Recent studies have given novel insight into the spatiotemporal regulation and molecular mechanisms controlling abscission in cultured yeast and human cells. The mechanisms of abscission in living metazoan tissues are however not well understood. Here we show that ALIX and the ESCRT-III component Shrub are required for completion of abscission during Drosophila female germline stem cell (fGSC) division. Loss of ALIX or Shrub function in fGSCs leads to delayed abscission and the consequent formation of stem cysts in which chains of daughter cells remain interconnected to the fGSC via midbody rings and fusome. We demonstrate that ALIX and Shrub interact and that they co-localize at midbody rings and midbodies during cytokinetic abscission in fGSCs. Mechanistically, we show that the direct interaction between ALIX and Shrub is required to ensure cytokinesis completion with normal kinetics in fGSCs. We conclude that ALIX and ESCRT-III coordinately control abscission in Drosophila fGSCs and that their complex formation is required for accurate abscission timing in GSCs in vivo.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Cycle / genetics*
  • Cytokinesis / genetics*
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster
  • Endosomal Sorting Complexes Required for Transport / genetics
  • Endosomal Sorting Complexes Required for Transport / metabolism
  • Endosomes / genetics
  • Female
  • Germ Cells / cytology
  • Germ Cells / metabolism
  • Humans
  • Microfilament Proteins / genetics*
  • Microfilament Proteins / metabolism
  • Nerve Tissue Proteins / genetics*
  • Nerve Tissue Proteins / metabolism
  • Oocytes / metabolism
  • Protein Interaction Maps / genetics
  • Stem Cells / cytology
  • Stem Cells / metabolism

Substances

  • ALIX protein, Drosophila
  • Drosophila Proteins
  • Endosomal Sorting Complexes Required for Transport
  • Microfilament Proteins
  • Nerve Tissue Proteins
  • Shrb protein, Drosophila