Anti-phospho-Syk (Tyr323) Antibody, Alexa Fluor(R) 488 Conjugate from rabbit, ALEXA FLUOR(R) 488

Tyrosine-protein kinase Syk (EC 2.7.10.2; UniProt P43405; also known as p72-Syk, p72Syk, Spleen tyrosine kinase) is encoded by the SYK gene (Gene ID 6850) in human. Spleen tyrosine kinase (Syk) is a non-receptor tyrosine kinase highly expressed by haematopoietic cells. Syk plays a crucial role not only in adaptive immune receptor signalling, but also in cellular adhesion, innate immune recognition, osteoclast maturation, platelet activation and vascular development. Syk adopts an autoinhibited conformation in its inactive state and is activated upon binding immunoreceptor tyrosine-based activation motifs (ITAMs) and phosphorylation of tyrosine residues in the two linker regions (a.a. 108-160 and 260-370) between SH1 (a.a. 15-107) and SH2 (a.a. 168-259), and between SH2 and the kinase domain (a.a. 371-631). Initial ITAM binding triggers rapid activation of Syk, whereas subsequent phosphorylation leads to prolonged activation. In additon, Syk can phosphorylate ITAMs and autophosphorylate its own link region tyrosines, providing a positive feedback loop following initial ITAM-mediated Syk activation. Syk also mediates signalling of receptors that do not contain an ITAM, including integrins and C-type lectins, via interaction with ITAM-containing adaptors, such as DAP12 (TYROBP) and the FcR gamma-chain (FcRgamma).