Four integrins, namely α 1 β 1, α 2 β 1, α 10 β 1, and α 11 β 1, form a special subclass of cell
adhesion receptors. They are all collagen receptors, and they recognize their ligands with
an inserted domain (I domain) in their α subunit. We have produced the human integrin α 10
I domain as a recombinant protein to reveal its ligand binding specificity. In general, α 10 I
did recognize collagen types I–VI and laminin-1 in a Mg 2+-dependent manner, whereas its
binding to tenascin was only slightly better than to albumin. When α 10 I was tested together …