SYK is a cytoplasmic signal transduction enzyme mainly located in hematopoietic system cells, which mediates specific phosphorylation cascade reactions through its tandem SH2 domains. The kinase triggers the transmembrane signal transduction mechanism by recognizing the phosphorylation sites of the immunoreceptor tyrosine activation motifs (ITAMs), and plays a core regulatory role in B cell receptor signal activation and FcεRI-mediated allergic response pathways.
