摘要
Laminin 伪2 chain plays an important role in basement membrane assembly and peripheral myelinogenesis; however, the integrin binding motif within human laminin 伪2 chain and the signaling pathways downstream of this ligand-receptor interaction are poorly understood. We identified a motif, RNIPPFEGCIWN (Ln2-LG3-P2), within LG3 domain of human laminin 伪2 chain as a major site for both 伪3尾1 integrin and cellular activities such as cell adhesion, spreading, and migration. Binding of 伪3尾1 integrin with Ln2-LG3-P2 induced the membrane recruitment of protein kinase C未 (PKC未) and stimulated its tyrosine phosphorylation. The cellular activities induced by Ln2-LG3-P2 and the phosphorylation of focal adhesion kinase (FAK) were inhibited by rottlerin, a PKC未 inhibitor, but not by G枚6976, a PKC伪/尾 inhibitor. These results indicate that RNIPPFEGCIWN motif within human laminin 伪2 chain is a major ligand for 伪3尾1 integrin, and that binding of 伪3尾1 integrin mediates cellular activities through membrane recruitment and tyrosine phosphorylation of PKC未 and FAK phosphorylation.