※ DDR family introduction

    DDR (Discoidin domain receptor) belong to receptor tyrosine kinase. DDRs exist in all animals. Two genes encoding DDR1 and DDR2 have been found in mammals. DDRs possess a typical RTK structure, including a signal peptide, an extracellular region, a transmembrane domain and an intracellular kinase domain. The discoidin domain exists in extracellular domain and mediates the collagen-binding. DDR1 is overexpressed in several cancers and is a direct transcriptional target of p53. Studies show that DDR1 can regulate cell spreading and motility by associating with myosin IIA and can also regulate the stabilization of cell surface E-cadherin and E-cadherin-mediated cell aggregation (1). DDR2 can act as a cell surface receptor for fibrillar collagen, and can regulate cell differentiation, remodeling of the extracellular matrix, cell migration and cell proliferation (2).

Reference
1. Huang, Y., Arora, P., McCulloch, C.A. and Vogel, W.F. (2009) The collagen receptor DDR1 regulates cell spreading and motility by associating with myosin IIA. J Cell Sci, 122, 1637-1646. PMID: 19401332
2. Uniprot annotation:   DDR2_HUMAN