MYLK Recombinant Rabbit mAb

MYLK is a calcium/calmodulin-dependent serine/threonine kinase that initiates actin-myosin crosslinking by phosphorylating the myosin regulatory light chain (MLC), thereby driving smooth muscle contraction and cytoskeletal remodeling. Alternative splicing of the gene generates multiple isoforms, including the smooth muscle type (smMLCK) and the non-muscle type (nmMLCK), and an internal promoter independently expresses telokin—a small protein identical in sequence to the C-terminus of MLCK—which stabilizes non-phosphorylated myosin filaments. Beyond classical contractile regulation, MLCK also participates in the regulation of endothelial and epithelial barrier function; MLC phosphorylation mediated by MLCK can trigger cell contraction and rearrangement of junctional proteins, leading to increased vascular permeability and impaired intestinal barrier function. In terms of pathological associations, loss-of-function mutations in MYLK can impair smooth muscle contractility and are associated with familial thoracic aortic aneurysm and dissection, while specific single-nucleotide polymorphisms in nmMLCK (such as P21H, S147P, and V261A) are significantly associated with susceptibility to asthma and acute lung injury, and transgenic mouse studies have further confirmed that nmMLCK expression levels are positively correlated with the severity of allergic airway inflammation.