Direct binding of collagen to the I domain of integrin alpha 2 beta 1 (VLA-2, CD49b/CD29) in a divalent cation-independent manner.
Integrin alpha 2 beta 1 is a major divalent cation-dependent receptor for collagen. Here, we show that the recombinant inserted/interactive domain (I domain) of alpha 2 specifically interacts with collagen, indicating the I domain contains all the components necessary for collagen binding. Evidence was obtained that divalent cations are not required for collagen binding to the I domain fragment, indicating that divalent cations are not involved in the actual binding to collagen but probably in the regulation of the binding. We identified Thr-221 within the previously identified putative ligand binding region as a residue critical for collagen binding to both alpha 2 beta 1 and the I domain fragment. Thr-221 may be involved in the actual collagen binding and recognition.
Kamata
T
T
Department of Vascular Biology, Scripps Research Institute, La Jolla, California 92037.
Takada
Y
Y
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D016466:CHO Cells; D003094:Collagen / Q000378:metabolism*; D006224:Cricetinae; D004492:Edetic Acid / Q000494:pharmacology; D005982:Glutathione Transferase / Q000378:metabolism; D019012:Integrin beta1; D016023:Integrins / Q000378:metabolism*; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008969:Molecular Sequence Data; D009154:Mutation; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013329:Structure-Activity Relationship
D015703:Antigens, CD; D019012:Integrin beta1; D016023:Integrins; D011993:Recombinant Fusion Proteins; D008345:Manganese; D003094:Collagen; D004492:Edetic Acid; D005982:Glutathione Transferase; D008274:Magnesium