RTKs play a key role in the communication of cells with their microenvironment. These molecules are involved in the regulation of cell growth, differentiation, and metabolism. In several cases the biochemical mechanism by which RTKs
transduce signals across the membrane has been shown to be ligand induced receptor oligomerization and subsequent intracellular
phosphorylation. In the case of DDR2, the ligand is
collagen which binds to its extracellular discoidin domain. This
autophosphorylation leads to phosphorylation of cytosolic targets as well as association with other molecules, which are involved in
pleiotropic effects of signal transduction. DDR2 has been associated with a number of diseases including
fibrosis and
cancer. == Structure ==