Vitronectin

Vitronectin is a cell adhesion and spreading factor found in serum and tissues that interacts with glycosaminoglycans and proteoglycans. It is recognized by certain members of the integrin family and serves as a cell-to-substrate adhesion molecule. It inhibits the membrane-damaging effect of the terminal cytolytic complement pathway. Vitronectin exists in two forms: a single chain 75 kDa form (V75) and a clipped form composed of two chains (65 kDa and 10 kDa) which are held together by a disulfide bond. The SMB domain mediates interaction with SERPINE1/PAI1 and the heparin-binding domain mediates interaction with insulin. Phosphorylation on Thr-69 and Thr-76 favors cell adhesion and spreading.

Swiss-Prot Accession Number: P04004