Prenylation of RhoB is required for its cell transforming function but not its ability to activate serum response element-dependent transcription.
Rho regulates cytoskeletal actin structure and integrin-mediated cell adhesion. Rho also has a role in cell growth regulation and is required for cell transformation by oncogenic Ras. Recently, it has been demonstrated that Rho can activate transcription from the c-fos serum response element (SRE). This raised the possibility that functions required for Rho-mediated cell transformation might overlap with those involved in transcriptional regulation. Here we show that RhoB can activate the SRE and can synergize in cell transformation with constitutively activated Raf-CAAX. Significantly, unprenylated forms of RhoB that are biologically inert and unable to transform cells can still activate SRE-dependent transcription. This finding suggests that transcriptional activation by Rho may be separable from its cell transforming functions.
Lebowitz
P F
PF
The Wistar Institute, Philadelphia, Pennsylvania 19104, USA.
Du
W
W
Prendergast
G C
GC
D016475:3T3 Cells; D000818:Animals; D002471:Cell Transformation, Neoplastic; D019204:GTP-Binding Proteins / Q000378:metabolism*; D016762:Genes, fos; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D017368:Protein Prenylation; D014158:Transcription, Genetic; D020743:rhoB GTP-Binding Protein
D008565:Membrane Proteins; D019204:GTP-Binding Proteins; D020743:rhoB GTP-Binding Protein