Protein Domain : Rho guanine nucleotide exchange factor 3, PH domain IPR044129

Type	Domain
Description	PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner [ ]. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity []. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane []. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes [].ARHGEF3 (also known as XPLN) is a guanine nucleotide exchange factor (GEF) for RhoA and RhoB GTPases [ ]. It contains a tandem Dbl homology and a PH domain. This entry represents the PH domain.
Short Name	PH_RhoGEF3_XPLN