B lymphoid kinase (BLK)

B lymphoid kinase (BLK) is a non-receptor tyrosine kinase belonging to the Src family, primarily expressed in B-lymphocytes and pancreatic beta-cells (UniProt, Wikipedia). In the immune system, BLK is a critical component of the B-cell receptor (BCR) signaling pathway, where it facilitates B-cell development, differentiation, and activation by phosphorylating downstream targets like CD79A and CD79B (UniProt, PubMed). In the pancreas, BLK modulates insulin secretion in response to glucose by upregulating key transcription factors such as PDX1 and NKX6-1 (PubMed, Open Targets). Dysregulation of BLK is implicated in several diseases; it acts as an oncogene when ectopically expressed in cutaneous T-cell lymphoma (CTCL) and is genetically linked to autoimmune conditions such as systemic lupus erythematosus (SLE) and metabolic disorders like maturity-onset diabetes of the young (MODY11) (PubMed, JensenLab). Due to its role in promoting malignant cell proliferation, BLK is a therapeutic target for kinase inhibitors like dasatinib and ibrutinib, with selective irreversible inhibitors currently under investigation to improve treatment specificity and reduce off-target effects (PubMed).

Other names

B lymphocyte kinaseTyrosine-protein kinase Blkp55-BlkMODY11BLK proto-oncogeneSrc family tyrosine kinase BLK

Inhibition of the kinase activity of B lymphoid kinase, typically by competing with ATP for the binding site in the catalytic domain, thereby blocking downstream signaling pathways involved in cell growth, survival, and immune activation.