HOPS is an essential constituent of centrosome assembly

Cell Cycle. 2008 May 15;7(10):1462-6. doi: 10.4161/cc.7.10.5882. Epub 2008 Mar 7.

Abstract

Centrosomes direct microtubule organization during cell division. Aberrant number of centrosomes results from alteration of its components and leads to abnormal mitoses and chromosome instability. HOPS is a newly discovered protein isolated during liver regeneration, implicated in cell proliferation. Here, we provide evidence that HOPS is an integral constituent of centrosomes. HOPS is associated with classical markers of centrosomes and found in cytosolic complexes containing CRM-1, gamma-tubulin, eEF-1A and HSP70. These features suggest that HOPS is involved in centrosome assembly and maintenance. HOPS depletion generates supernumerary centrosomes, multinucleated cells and multipolar spindle formation leading to activation of p53 checkpoint and cell cycle arrest. The presence of HOPS in cytosolic complexes supports that centrosome proteins might be preassembled in the cytoplasm to then be rapidly recruited for centrosome duplication. Altogether these data show HOPS implication in the control of cell division. HOPS contribution appears relevant to understand genomic instability and centrosome amplification in cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Division / physiology*
  • Centrosome / metabolism
  • Centrosome / physiology*
  • Fluorescent Antibody Technique
  • Genomic Instability / physiology*
  • Immunoblotting
  • Immunoprecipitation
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • Mice
  • Multiprotein Complexes / metabolism*
  • NIH 3T3 Cells
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Oligonucleotides

Substances

  • Carrier Proteins
  • HOPS protein, mouse
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • Multiprotein Complexes
  • Nuclear Proteins
  • Oligonucleotides