Location of Repository

Evidence for distinct mechanisms of transition state stabilization of GTPases by fluoride

By Sylvie Vincent, Madeleine Brouns, Matthew J. Hart and Jeffrey Settleman


GTPase-activating proteins (GAPs) function by stabilizing the GTPase transition state. This has been most clearly demonstrated by the formation of a high-affinity complex between various GAPs and GDP-bound GTPases in the presence of aluminum tetrafluoride, which can mimic the γ-phosphate of GTP. Herein, we report that p190 RhoGAP forms a high-affinity complex with Rho GTPases in the presence of fluoride ions, suggesting that p190 also functions to stabilize the GTPase transition state. However, this Rho–p190 complex does not require aluminum ions or even guanine nucleotide, indicating a distinct role for fluoride that is not consistent with the γ-phosphate-mimicking hypothesis. These results indicate that it is necessary to reconsider the assumed role of fluoride in stabilizing a variety of other GTPase–GAP interactions where the requirement for aluminum or guanine nucleotide has not yet been addressed

Topics: Biological Sciences
Publisher: The National Academy of Sciences
Year: 1998
OAI identifier: oai:pubmedcentral.nih.gov:19296
Provided by: PubMed Central
Sorry, our data provider has not provided any external links therefore we are unable to provide a link to the full text.

Suggested articles

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.