Signaling through Galpha12/13 and RGS-RhoGEFs



The transforming heterotrimeric G proteins Gα12 and Gα13 have been implicated in the regulation of various cellular processes, such as gene transcription and rearrangement of the actin-based cytoskeleton. Many of these functions are dependent on the activation of the monomeric GTPase RhoA. The RGS-RhoGEFs, a distinct family of guanine nucleotide exchange factors, which contain RGS-like domains in their N-termini, serve as direct links between Gα12/13 and RhoA. The focus of this chapter is on the molecular mechanisms that underlie and regulate signaling from Gα12/13 to RhoA via the RGS-RhoGEFs. The physiological significance of this signaling pathway is also discussed.


Acute Myeloid Leukemia Guanine Nucleotide Exchange Factor Neurite Retraction Guanine Nucleotide Exchange Activity Nucleotide Exchange Rate 
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We would like to apologize to our colleagues whose contributions to this field were inadvertently omitted or could not be properly acknowledged due to space limitations.


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Authors and Affiliations

  1. 1.Department of PharmacologyCollege of Medicine, University of Illinois at ChicagoChicagoUSA

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