Phosphorylation-dependent regulation of the F-BAR protein Hof1 during cytokinesis

Genes Dev. 2011 Apr 15;25(8):875-88. doi: 10.1101/gad.622411.

Abstract

Spatial and timely coordination of cytokinesis is crucial for the maintenance of organelle inheritance and genome integrity. The mitotic exit network (MEN) pathway controls both the timely initiation of mitotic exit and cytokinesis in budding yeast. Here we identified the conserved F-BAR protein Hof1 as a substrate of the MEN kinase complex Dbf2-Mob1 during cytokinesis. We show that polo-like kinase Cdc5 first phosphorylates Hof1 to allow subsequent phosphorylation by Dbf2-Mob1. This releases Hof1 from the septin ring and facilitates Hof1 binding to the medial actomyosin ring (AMR), where Hof1 promotes AMR contraction and membrane ingression. Domain structure analysis established that the central, unstructured, region of Hof1, named the ring localization sequence (RLS), is sufficient to mediate Hof1's binding to the medial ring in a cell cycle-dependent manner. Genetic and functional data support a model in which Dbf2-Mob1 regulates Hof1 by inducing domain rearrangements, leading to the exposure of the Hof1 RLS domain during telophase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Cell Cycle / genetics
  • Cell Cycle / physiology
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Cytokinesis / genetics
  • Cytokinesis / physiology*
  • Immunoprecipitation
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism*
  • Mitosis / genetics
  • Mitosis / physiology
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism
  • Phosphorylation
  • Protein Kinases / genetics
  • Protein Kinases / metabolism
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Cell Cycle Proteins
  • HOF1 protein, S cerevisiae
  • MOB1 protein, S cerevisiae
  • Microtubule-Associated Proteins
  • Phosphoproteins
  • Saccharomyces cerevisiae Proteins
  • Protein Kinases
  • DBF2 protein, S cerevisiae
  • Protein Serine-Threonine Kinases
  • CDC5 protein, S cerevisiae