LIMK1 (Ser-323) [LIMK2 (Ser-314) ], Phosphospecific Antibody

LIM kinases (LIMK1 and LIMK2) are serine/threonine kinases that have two zinc finger motifs, known as LIM motifs, in their amino-terminal regulatory domains. LIM kinases are involved in actin cytoskeletal regulation downstream of Rho-family GTPases, PAKs, and ROCK. PAK1 and ROCK phosphorylate LIMK1 or LIMK2 at the conserved Thr-508 or Thr-505 residues in the activation loop, increasing LIMK activity. In addition, VEGF-induced stress fiber formation has been linked to p38-mediated activation of LIMK through MK-2 phosphorylation of Ser-323. Activated LIM kinases inhibit the actin depolymerization activity of cofilin by phosphorylation at the amino-terminal Ser-3 residue of cofilin. In addition, LIMKs may have a function in the nucleus. It has been shown that the nuclear localization of LIMKs can mediate suppression of Rac/Cdc42-mediated cyclin D1 expression. This effect of LIMKs was independent of cofilin phosphorylation and the regulation of actin dynamics.

This antibody was cross-adsorbed to unphosphorylated LIMK1 (Ser-323) peptide then Affinity purification using LIMK1 (Ser-323) peptide (without carrier) . The antibody detects a protein with the same mobility as anti-LIMK1 (C-terminus, LP1831) in human A431 cells treated with calyculin A. This band is weak in control cells and is not detected after lambda phosphatase treatment. This sequence is conserved in rat and mouse LIMK1, and has high homology to Ser-314 in human LIMK2.