P-Rex2 (PIP3-dependent Rac exchanger 2, PREX2) is a Dbl-type guanine-nucleotide exchange factor (GEF) that activates the small G protein (small GTPase) Rac1, a member of the Rho family. P-Rex2 was discovered in 2004 on the basis of its homology to P-Rex1 (Donald et al. 2004; Rosenfeldt et al. 2004). Like P-Rex1, P-Rex2 is synergistically activated by the lipid second messenger phosphatidyl inositol (3,4,5)-trisphosphate (PIP3), which is generated by phosphoinositide 3-kinase (PI3K), and by the Gβγ subunits of heterotrimeric G proteins, which are released upon the activation of G protein-coupled receptors (GPCRs) (Donald et al. 2004; Li et al. 2005). Studies using genetically modified mice showed that P-Rex2 controls the dendrite morphology and synaptic plasticity of cerebellar Purkinje neurons...
This review was funded by Institute Strategic Programme Grant BB/J004456/1 from the Biotechnology and Biological Sciences Research Council (BBSRC) to the Babraham Institute Signalling Programme. ET is funded by a CASE PhD studentship from the BBSRC in collaboration with the Cardiovascular and Metabolic Disease unit of MedImmune, Cambridge. CP is funded by a Targeted PhD studentship from the BBSRC Doctoral Training Programme.