Primary Identifier | IPR037702 | Type | Domain |
Short Name | PI3Kbeta_dom |
description | This entry represents the catalytic domain of PI3Kbeta (also known as p110beta), which is a Class IA phosphoinositide-3-kinase (PI3K) that phosphorylates PtdIns (Phosphatidylinositol), PtdIns4P (Phosphatidylinositol 4-phosphate) and PtdIns(4,5)P2 (Phosphatidylinositol 4,5-bisphosphate) to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3). It has been shown to regulate chromosome segregation in mitosis [].PI3Ks can be divided into three main classes (I, II, and III), defined by their substrate specificity, regulation, and domain structure. Class I PI3Ks are the only enzymes capable of converting PtdIns(4,5)P2 to the critical second messenger PtdIns(3,4,5)P3. Class I enzymes are heterodimers and exist in multiple isoforms consisting of one catalytic subunit (p110alpha, beta, gamma or delta) and one of several regulatory subunits (p85alpha, beta or gamma). They are further classified into class IA (alpha, beta and delta) and IB (gamma). Class IA enzymes contain an N-terminal p85 binding domain, a Ras binding domain, a lipid binding C2 domain, a PI3K homology domain of unknown function, and a C-terminal ATP-binding cataytic domain. They associate with a regulatory subunit of the p85 family and are activated by tyrosine kinase receptors []. |