Interaction of Galpha 12 and Galpha 13 with the cytoplasmic domain of cadherin provides a mechanism for beta -catenin release.

Autor: Meigs TE; Departments of Pharmacology and Cancer Biology, and Pathology, Duke University Medical Center, Durham, NC 27710, USA., Fields TA, McKee DD, Casey PJ
Jazyk: angličtina
Zdroj: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2001 Jan 16; Vol. 98 (2), pp. 519-24. Date of Electronic Publication: 2001 Jan 02.
DOI: 10.1073/pnas.98.2.519
Abstrakt: The G12 subfamily of heterotrimeric G proteins, comprised of the alpha-subunits Galpha12 and Galpha13, has been implicated as a signaling component in cellular processes ranging from cytoskeletal changes to cell growth and oncogenesis. In an attempt to elucidate specific roles of this subfamily in cell regulation, we sought to identify molecular targets of Galpha12. Here we show a specific interaction between the G12 subfamily and the cytoplasmic tails of several members of the cadherin family of cell-surface adhesion proteins. Galpha12 or Galpha13 binding causes dissociation of the transcriptional activator beta-catenin from cadherins. Furthermore, in cells lacking the adenomatous polyposis coli protein required for beta-catenin degradation, expression of mutationally activated Galpha12 or Galpha13 causes an increase in beta-catenin-mediated transcriptional activation. These findings provide a potential molecular mechanism for the previously reported cellular transforming ability of the G12 subfamily and reveal a link between heterotrimeric G proteins and cellular processes controlling growth and differentiation.
Databáze: MEDLINE