Structural basis of the collagen-binding mode of discoidin domain receptor 2

Abstract
Discoidin domain receptor (DDR) is a cell‐surface receptor tyrosine kinase activated by the binding of its discoidin (DS) domain to fibrillar collagen. Here, we have determined the NMR structure of the DS domain in DDR2 (DDR2‐DS domain), and identified the binding site to fibrillar collagen by transferred cross‐saturation experiments. The DDR2‐DS domain structure adopts a distorted jellyroll fold, consisting of eight β‐strands. The collagen‐binding site is formed at the interloop trench, consisting of charged residues surrounded by hydrophobic residues. The surface profile of the collagen‐binding site suggests that the DDR2‐DS domain recognizes specific sites on fibrillar collagen. This study provides a molecular basis for the collagen‐binding mode of the DDR2‐DS domain.