Src-family kinase Src homology 2 domain (SFK SH2 domain) (SFK SH2 domain)

The Src-family kinase Src homology 2 (SH2) domain is a specialized protein module of approximately 100 amino acids that plays a pivotal role in cellular signaling by binding to phosphotyrosine-containing sequences [Source: UniProt]. In Src-family kinases (SFKs), this domain is essential for both the recruitment of the kinase to activated receptors and the autoinhibitory regulation of the enzyme's catalytic activity [Source: PubMed]. When the C-terminal tyrosine of an SFK is phosphorylated, the SH2 domain binds to it, locking the kinase in an inactive state; displacement of this interaction by other phosphoproteins activates the kinase [Source: NIH]. Aberrant SFK signaling, often driven by SH2-mediated interactions, is a hallmark of many cancers, contributing to tumor growth, metastasis, and resistance to therapy [Source: Nature Reviews Cancer]. Although most FDA-approved SFK inhibitors like Dasatinib target the ATP-binding pocket, the SH2 domain is an attractive target for developing highly specific protein-protein interaction (PPI) inhibitors [Source: Journal of Medicinal Chemistry]. Such inhibitors, including experimental peptidomimetics and small molecules like AP22408, aim to block the recruitment of SFKs to signaling complexes without the off-target issues associated with ATP-competitive drugs [Source: PubMed].

Other names

SH2 domainSrc homology 2 domainSFK SH2

Disruption of phosphotyrosine-mediated protein-protein interactions and allosteric modulation of kinase activity.