Editors' ChoiceHeterotrimeric G Proteins

G Proteins that Link to Cadherins

Science's STKE  23 Jan 2001:
Vol. 2001, Issue 66, pp. tw4
DOI: 10.1126/stke.2001.66.tw4

The Gα12 subfamily of heterotrimeric G proteins has been implicated in regulating cell growth and transformation. Meigs et al. now propose that it does so by affecting the cadherin-β-catenin signaling pathway. Purified cytoplasmic domain of cadherin and purified Gα12 directly associated in vitro, and overexpression of Gα12 in cultured cells resulted in displacement of β-catenin from associated cadherin. The authors propose that at the cell surface, Gα12 binds to the cadherin cytoplasmic domain, causing release of β-catenin to the nucleus to affect transcription. Degradation of cytosolic β-catenin would also have to be inhibited for this to occur.

T. E. Meigs, T. A. Fields, D. D. McKee, P. J. Casey, Interaction of Gα12 and Gα13 with the cytoplasmic domain of cadherin provides a mechanism for β-catenin release. Proc. Natl. Acad. Sci. U.S.A. 98, 519-524 (2001). [Abstract] [Full Text]