Purification and functional characterization of integrin alpha v beta 5. An adhesion receptor for vitronectin.

摘要: We have purified a novel member of the integrin gene family from placenta that serves as vitronectin receptor. This is composed alpha v subunit and beta we designate 5. Purification was accomplished by immunodepleting placental extract 3, allowing us to purify 5 remaining monoclonal antibody affinity chromatography on LM 142-Sepharose, which binds subunit. homogeneity subsequently achieved wheat germ lectin-Sepharose. Western blot analysis with antibodies raised against 3 demonstrated were distinct but confirmed two integrins immunologically identical. Similarly, bind proximal ligand-binding site failed react 5, indicating an architectural difference at these related integrins. structural apparently results in functional distinction, since bound vitronectin, fibrinogen, von Willebrand factor, fibronectin, whereas preferentially vitronectin. Finally, demonstrate three criteria x, latter identified lung carcinoma cells (Cheresh, D. A., Smith, J. W., Cooper, H. M., Quaranta, V. (1989) Cell 57, 59-69), are First, peptide maps x Secondly, polyclonal immunoprecipitate both finally, amino-terminal amino acid sequences