IGBP1 (5F6) Mouse mAb #5699

Immunoglobulin binding protein 1 (IGBP1) interacts with the regulatory subunit C of serine/threonine phosphatase PP2A, and other protein phosphotases, PP4 and PP6 (1-3). Binding of IGBP1 to PP2A has been shown to regulate PP2A catalytic activity and its substrate specificity (1-4). Recent evidence suggests that IGBP1 may play a role in PP2Ac ubiquitination via its association with E3 ubiquitin ligase MID1 (5,6). IGBP1 negatively regulates apoptosis by targeting PP2A activity to suppress p38 mitogen-activated protein kinase activation by cytokines (7). Upon BCR cross-linking, IGBP1 transiently associates with tyrosine phosphorylated molecules, which in turn induce downstream signal transduction (7). Evidence suggests that IGBP1 association with PP2A may be involved in the rapamycin sensitive mTOR pathway (8,9). Formation of the IGBP1 and Midline ring finger protein (MID) complex has been identified as a prerequisite to pathogenesis of X-linked Optiz GBBB syndrome (10).