Human/Mouse/Rat SH2B1 Antibody

SH2B1 (Src-Homology 2 Domain-Containing protein B1/1B; also SH2B1 alpha, PSM and SH2B adaptor protein 1) is a member of the SH2B adapter family of proteins. Although its predicted MW is 80 kDa, it runs anomalously at 90-102 kDa in SDS-Page. SH2B1 is a nucleocytoplasmic protein that is widely expressed in cells such as skeletal muscle cells, neurons, and adipocytes. It serves as a linker between Jak2 and multiple downstream molecules such as Rac and IRS1. It does this following phosphorylation on a number of potential sites. It also promotes the enzymatic activity of associated receptor kinases, thus potentiating ligand-receptor interactions. SH2B1 appears to bind to nonphosphorylated Jaks as a monomer, while Jak phosphorylation induces SH2B1 dimerization. SH2B1 is further reported to form a homopentamer, and to oligomerize with SH2B2. Human SH2B1( alpha) is 756 amino acids amino acids (aa) in length. It contains one dimerization segment (aa 24-85), an NLS (aa 224-233), one pleckstrin homology region (aa 249-378) and an SH2 domain (aa 521-625). At least three utilized phosphorylation sites exist. There are at least two splice variants for SH2B1. The 90-92 kDa SH2B1 beta isoform shows a 39 aa substitution for aa 633-756, while the SH2B1 gamma isoform possesses a 50 aa substitution for the same aa range (i.e., aa 633-756). Over aa 317-467, human SH2B1 shares 92% aa identity with mouse SH2B1.