MASTL is the human orthologue of Greatwall kinase that facilitates mitotic entry, anaphase and cytokinesis

Cell Cycle. 2010 Sep 1;9(17):3591-601. doi: 10.4161/cc.9.17.12832. Epub 2010 Sep 29.

Abstract

Greatwall (Gwl) was originally discovered in Drosophila as an essential kinase for correct chromosome condensation and mitotic progression. In Xenopus, Gwl may influence the positive-feedback loop that directs cyclin B1-Cdk1 activation and the mitotic state by inhibiting the phosphatase PP 2A. Here, we describe the human orthologue of Gwl called microtubule-associated serine/threonine kinase-like (MASTL). We found that MASTL localizes to the nucleus in interphase and re-localizes in part to centrosomes in mitosis, when it is active. Cells strongly depleted of MASTL by RNAi delay in G(2) phase and reveal slow chromosome condensation. MASTL RNAi cells that enter and progress through mitosis often fail to completely separate their sister chromatids in anaphase. This causes chromatin to be trapped in the cleavage furrow, which may lead to the formation of 4N G(1) cells by cytokinesis failure. Further, our experiments indicate that MASTL supports the phosphorylation state of mitotic phospho-proteins downstream of cyclin B1-Cdk1, including the APC/C. Cyclin B1 destruction is incomplete when mitotic cells that are strongly depleted of MASTL exit mitosis. We propose that MASTL enhances cyclin B1-Cdk1-dependent mitotic phosphorylation events, directing mitotic entry, anaphase and cytokinesis in human cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaphase*
  • CDC2 Protein Kinase / metabolism
  • Cell Line, Tumor
  • Cell Nucleus / metabolism
  • Cyclin B1 / metabolism
  • Cytokinesis / physiology*
  • G2 Phase
  • Humans
  • Microtubule-Associated Proteins / analysis
  • Microtubule-Associated Proteins / genetics
  • Microtubule-Associated Proteins / metabolism*
  • Mitosis*
  • Phosphorylation
  • Protein-Serine-Threonine Kinases / analysis
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • RNA Interference
  • RNA, Small Interfering / metabolism

Substances

  • Cyclin B1
  • Microtubule-Associated Proteins
  • RNA, Small Interfering
  • MASTL protein, human
  • Protein-Serine-Threonine Kinases
  • CDC2 Protein Kinase