Inhibition of RhoA-mediated SRF activation by p116Rip

FEBS Lett. 2005 Nov 7;579(27):6121-7. doi: 10.1016/j.febslet.2005.09.083. Epub 2005 Oct 13.

Abstract

p116Rip, originally identified as a binding partner of activated RhoA, is an actin-binding protein that interacts with the regulatory myosin-binding subunit (MBS) of myosin-II phosphatase and is essential for Rho-regulated cytoskeletal contractility. Here, we have examined the role of p116Rip in RhoA-mediated activation of the transcription factor SRF. We show that p116Rip oligomerizes via its C-terminal coiled-coil domain and, when overexpressed, inhibits RhoA-induced SRF activation without affecting RhoA-GTP levels. Mutant forms of p116Rip that fail to oligomerize or bind to MBS are still capable of inhibiting SRF activity. Our results suggest that p116Rip interferes with RhoA-mediated transcription through its ability to disassemble the actomyosin cytoskeleton downstream of RhoA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cells, Cultured
  • Humans
  • Mice
  • Microfilament Proteins / genetics
  • Microfilament Proteins / physiology*
  • Molecular Sequence Data
  • Mutation
  • Myosin Light Chains / metabolism
  • Protein Structure, Tertiary
  • Serum Response Element / genetics
  • Serum Response Factor / antagonists & inhibitors*
  • Serum Response Factor / metabolism
  • Transcription, Genetic
  • rhoA GTP-Binding Protein / antagonists & inhibitors*
  • rhoA GTP-Binding Protein / metabolism

Substances

  • Microfilament Proteins
  • Myosin Light Chains
  • Serum Response Factor
  • p116Rip protein, mouse
  • rhoA GTP-Binding Protein