Alpha(E)-Catenin induces SRF-dependent transcriptional activity through its C-terminal region and is partly RhoA/ROCK-dependent

Biochem Biophys Res Commun. 2008 Feb 15;366(3):717-23. doi: 10.1016/j.bbrc.2007.12.012. Epub 2007 Dec 17.

Abstract

The ubiquitous alpha(E)-catenin is an essential actin cytoskeletal linker. The transcription factor, serum response factor (SRF), induces transcription via binding to the serum response element (SRE) in gene promoters, and in many cases responds to actin dynamics. Here, we report that alpha(E)-catenin expression in HEK293 cells activates the SRE.L transcriptional reporter, a reporter containing the isolated SRF-binding site, and a stably integrated SRE.L reporter in fibroblasts. alpha-Catenin-induced reporter activity appears only partly dependent on RhoA GTPase and Rho kinase function. alpha-Catenin expression has no effect on RhoA activation or localization, and alpha-catenin-induced SRE.L reporter activation is insensitive to the actin-modulating agent latrunculin B. Ectopic alpha-catenin expression was not sufficient to induce actin filament assembly as measured by stress fiber formation. SRE.L reporter is activated by the C-terminal approximately 300 residue region of alpha(E)-catenin. These results suggest induction of SRF-mediated transcription by alpha(E)-catenin either downstream of RhoA or via a parallel pathway.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Humans
  • Kidney / metabolism*
  • Protein Structure, Tertiary
  • Serum Response Factor / metabolism*
  • Signal Transduction / physiology
  • Transcriptional Activation / physiology*
  • alpha Catenin / metabolism*
  • rho-Associated Kinases / metabolism*
  • rhoA GTP-Binding Protein / metabolism*

Substances

  • SRF protein, human
  • Serum Response Factor
  • alpha Catenin
  • rho-Associated Kinases
  • rhoA GTP-Binding Protein