| Spatial control of Cdc42 signalling by a GM130-RasGRF complex regulates polarity and tumorigenesis. | | Spatial control of Cdc42 signalling by a GM130-RasGRF complex regulates polarity and tumorigenesis. | Baschieri F, Confalonieri S, Bertalot G, Di Fiore PP, Dietmaier W, Leist M, Crespo P, Macara IG, Farhan H. Nat Commun. 2014 Sep 11;5:4839. | 2014-09-06T22:00:00Z | <div style="text-align:justify;"></div><p style="text-align:justify;"><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2"><span class="ms-rteThemeForeColor-2-5 ms-rteThemeFontFace-1 ms-rteFontSize-2" style="font-weight:bold;">Abstract</span><br></span></p><div style="color:#000000;font-family:arial, helvetica, clean, sans-serif;text-align:justify;"><p style="margin-bottom:0.5em;font-size:1.04em;"><span class="ms-rteThemeFontFace-1 ms-rteFontSize-2">The small GTPase Cdc42 is a key regulator of polarity, but little is known in mammals about its spatial regulation and the relevance of spatial Cdc42 pools for polarity. Here we report the identification of a GM130-RasGRF complex as a regulator of Cdc42 at the Golgi. Silencing GM130 results in RasGRF-dependent inhibition of the Golgi pool of Cdc42, but does not affect Cdc42 at the cell surface. Furthermore, active Cdc42 at the Golgi is important to sustain asymmetric front-rear Cdc42-GTP distribution in directionally migrating cells. Concurrent to Cdc42 inhibition, silencing GM130 also results in RasGRF-dependent Ras-ERK pathway activation. Moreover, depletion of GM130 is sufficient to induce E-cadherin downregulation, indicative of a loss in cell polarity and epithelial identity. Accordingly, GM130 expression is frequently lost in colorectal and breast cancer patients. These findings establish a previously unrecognized role for a GM130-RasGRF-Cdc42 connection in regulating polarity and tumorigenesis.</span></p></div> | <p><span style="color:#474f51;font-family:"yanone kaffeesatz";font-size:18px;background-color:#ffffff;">[</span><a href="http://www.ncbi.nlm.nih.gov/pubmed/25208761" style="color:#ed391b;margin:0px;padding:0px;border:0px;font-stretch:inherit;font-size:18px;line-height:inherit;font-family:"yanone kaffeesatz";vertical-align:baseline;background-color:#ffffff;">PubMed</a><span style="color:#474f51;font-family:"yanone kaffeesatz";font-size:18px;background-color:#ffffff;">]</span><br></p> | 51 | | |
