Par-1 regulates stability of the posterior determinant Oskar by phosphorylation

Nat Cell Biol. 2002 May;4(5):337-42. doi: 10.1038/ncb782.

Abstract

Par-1 kinase is critical for polarization of the Drosophila melanogaster oocyte and the one-cell Caenorhabditis elegans embryo. Although Par-1 localizes specifically to the posterior pole in both cells, neither its targets nor its function at the posterior pole have been elucidated. Here we show that Drosophila Par-1 phosphorylates the posterior determinant Oskar (Osk) and demonstrate genetically that Par-1 is required for accumulation of Osk protein. We show in cell-free extracts that Osk protein is intrinsically unstable and that it is stabilized after phosphorylation by Par-1. Our data indicate that posteriorly localized Par-1 regulates posterior patterning by stabilizing Osk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions / metabolism
  • Animals
  • Body Patterning*
  • Caenorhabditis elegans / embryology
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins*
  • Cysteine Endopeptidases / metabolism
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / embryology
  • Drosophila melanogaster / metabolism
  • Embryo, Nonmammalian / anatomy & histology
  • Embryo, Nonmammalian / physiology*
  • Female
  • Models, Biological
  • Multienzyme Complexes / metabolism
  • Ovary / chemistry
  • Ovary / metabolism
  • Phosphorylation
  • Proteasome Endopeptidase Complex
  • Protein-Serine-Threonine Kinases / genetics
  • Protein-Serine-Threonine Kinases / metabolism*
  • Recombinant Fusion Proteins / metabolism
  • Tissue Extracts / chemistry
  • Tissue Extracts / metabolism
  • Ubiquitin / metabolism
  • Xenopus laevis / metabolism

Substances

  • 3' Untranslated Regions
  • Caenorhabditis elegans Proteins
  • Drosophila Proteins
  • Multienzyme Complexes
  • Recombinant Fusion Proteins
  • Tissue Extracts
  • Ubiquitin
  • osk protein, Drosophila
  • PAR-1 protein, C elegans
  • Protein-Serine-Threonine Kinases
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex