1CK4:
reference: Crystal structure of the alpha1beta1 integrin I-domain: insights into integrin I-domain function., Nolte M, Pepinsky RB, Venyaminov SYu, Koteliansky V, Gotwals PJ, Karpusas M, FEBS Lett 1999 Jun 11;452(3):379-85. PMID: 10386626

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