C-RAF activation promotes BAD poly-ubiquitylation and turn-over by the proteasome

Biochem Biophys Res Commun. 2008 Jun 13;370(4):552-6. doi: 10.1016/j.bbrc.2008.03.141. Epub 2008 Apr 8.

Abstract

BAD, a member of the BCL2 family, exhibits an original mode of regulation by phosphorylation. In the present report, we examine the role of the kinase C-RAF in this process. We show that the inducible activation of C-RAF promotes the rapid phosphorylation of BAD on Serine-112 (Ser-75 in the human protein), through a cascade involving the kinases MEK and RSK. Our findings reveal a new aspect of the regulation of BAD protein and its control by the RAF pathway: we find that C-RAF activation promotes BAD poly-ubiquitylation in a phosphorylation-dependent fashion, and increases the turn-over of this protein through proteasomal degradation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Humans
  • Mice
  • NIH 3T3 Cells
  • Phosphorylation
  • Polyubiquitin / metabolism*
  • Proteasome Endopeptidase Complex / metabolism*
  • Proto-Oncogene Proteins c-raf / metabolism*
  • Serine / metabolism
  • Ubiquitination*
  • bcl-Associated Death Protein / genetics
  • bcl-Associated Death Protein / metabolism*

Substances

  • BAD protein, human
  • bcl-Associated Death Protein
  • Polyubiquitin
  • Serine
  • Proto-Oncogene Proteins c-raf
  • Proteasome Endopeptidase Complex