TY - JOUR T1 - Structure and Function of Heterotrimeric G Protein-Regulated Rho Guanine Nucleotide Exchange Factors JF - Molecular Pharmacology JO - Mol Pharmacol SP - 111 LP - 125 DO - 10.1124/mol.109.061234 VL - 77 IS - 2 AU - Mohamed Aittaleb AU - Cassandra A. Boguth AU - John J. G. Tesmer Y1 - 2010/02/01 UR - http://molpharm.aspetjournals.org/content/77/2/111.abstract N2 - Activation of certain classes of G protein-coupled receptors (GPCRs) can lead to alterations in the actin cytoskeleton, gene transcription, cell transformation, and other processes that are known to be regulated by Rho family small-molecular-weight GTPases. Although these responses can occur indirectly via cross-talk from canonical heterotrimeric G protein cascades, it has recently been demonstrated that Dbl family Rho guanine nucleotide exchange factors (RhoGEFs) can serve as the direct downstream effectors of heterotrimeric G proteins. Heterotrimeric Gα12/13, Gαq, and Gβγ subunits are each now known to directly bind and regulate RhoGEFs. Atomic structures have recently been determined for several of these RhoGEFs and their G protein complexes, providing fresh insight into the molecular mechanisms of signal transduction between GPCRs and small molecular weight G proteins. This review covers what is currently known about the structure, function, and regulation of these recently recognized effectors of heterotrimeric G proteins. ER -