Regulation of MBK-2/Dyrk kinase by dynamic cortical anchoring during the oocyte-to-zygote transition

Curr Biol. 2007 Sep 18;17(18):1545-54. doi: 10.1016/j.cub.2007.08.049.

Abstract

Background: Successful transition from oocyte to zygote depends on the timely degradation of oocyte proteins to prepare for embryonic development. In C. elegans, degradation of the oocyte protein MEI-1 depends on MBK-2, a kinase that phosphorylates MEI-1 shortly after fertilization during the second meiotic division.

Results: Here we report that precise timing of MEI-1 phosphorylation depends on the cell cycle-regulated release of MBK-2 from the cortex. Prior to the meiotic divisions, MBK-2 is tethered at the cortex by EGG-3, an oocyte protein required for egg activation (see [1], accompanying paper in this issue). During the meiotic divisions, EGG-3 is internalized and degraded in an APC/C (anaphase-promoting complex/cyclosome)-dependent manner. EGG-3 internalization and degradation correlate with MBK-2 release from the cortex and MEI-1 phosphorylation in the cytoplasm. In an egg-3 mutant, MEI-1 is phosphorylated and degraded prematurely.

Conclusion: We suggest that successful transition from an oocyte to a zygote depends on the cell cycle-regulated relocalization of key regulators from the cortex to the cytoplasm of the egg.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism*
  • Amino Acid Sequence
  • Animals
  • Caenorhabditis elegans / embryology
  • Caenorhabditis elegans / enzymology*
  • Caenorhabditis elegans / growth & development
  • Caenorhabditis elegans Proteins / analysis
  • Caenorhabditis elegans Proteins / chemistry
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Caenorhabditis elegans Proteins / physiology*
  • Gene Expression Regulation, Developmental
  • Green Fluorescent Proteins / analysis
  • Meiosis
  • Molecular Sequence Data
  • Oocytes / enzymology*
  • Oocytes / growth & development
  • Phosphorylation
  • Protein Tyrosine Phosphatases / chemistry
  • Protein Tyrosine Phosphatases / genetics
  • Protein Tyrosine Phosphatases / physiology*
  • Protein-Tyrosine Kinases / analysis
  • Protein-Tyrosine Kinases / metabolism*
  • Recombinant Fusion Proteins / analysis
  • Ubiquitin-Protein Ligases / metabolism
  • Zygote / enzymology
  • Zygote / growth & development
  • Zygote / metabolism

Substances

  • Caenorhabditis elegans Proteins
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins
  • Ubiquitin-Protein Ligases
  • MBK-2 protein, C elegans
  • Protein-Tyrosine Kinases
  • EGG-3 protein, C elegans
  • Protein Tyrosine Phosphatases
  • Adenosine Triphosphatases
  • MEI-1 protein, C elegans