δ1-Catenin (Tyr-228), Phosphospecific Antibody

Catenins have emerged as molecular sensors that integrate cell-cell junctions and cytoskeletal dynamics with signaling pathways that control morphogenesis and cell to cell communication. δ1-Catenin (p120 catenin) is a catenin family member which contains an N-terminal coiled-coil domain, a regulatory domain containing multiple phosphorylation sites, and a central Armadillo repeat domain. δ1-Catenin regulates E-cadherin turnover, and has both positive and negative effects on cadherin-mediated adhesion. Actin dynamics are also regulated by δ1-Catenin, which can modulate RhoA, Rac and cdc42 activity. δ1-Catenin is phosphorylated at multiple tyrosine, serine and threonine sites both in vitro and in vivo. High levels of δ1-Catenin phosphorylated at Tyr-228 are commonly seen in several carcinoma cell lines and after EGFR activation. Many other tyrosine sites are also phosphorylated in the N-terminal region including Tyr-96, Tyr-112, Tyr-280, and Tyr-302. In addition, Thr-310 and Thr-916 are constituitively phosphorylated in many cell types, however this phosphorylation may occur only in δ1-Catenin associated with the plasma membrane.

The antibody detects a 110 kDa* protein corresponding to the molecular mass of δ1-Catenin on SDS-PAGE immunoblots of human A431 and HUVEC cells treated with pervanadate. This antibody does not detect this band after alkaline phosphatase treatment. This peptide sequence is highly conserved in rat and mouse δ1-Catenin.