GEF means go: turning on RHO GTPases with guanine nucleotide-exchange factors.

Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
Nature Reviews Molecular Cell Biology (Impact Factor: 36.46). 03/2005; 6(2):167-80. DOI: 10.1038/nrm1587
Source: PubMed

ABSTRACT Guanine nucleotide-exchange factors (GEFs) are directly responsible for the activation of Rho-family GTPases in response to diverse extracellular stimuli, and ultimately regulate numerous cellular responses such as proliferation, differentiation and movement. With 69 distinct homologues, Dbl-related GEFs represent the largest family of direct activators of Rho GTPases in humans, and they activate Rho GTPases within particular spatio-temporal contexts. The failure to do so can have significant consequences and is reflected in the aberrant function of Dbl-family GEFs in some human diseases.

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