May mediate the transduction of intracellular signals. Interacts with DOCK2 and EPOR. Interacts with phosphorylated CBLB and IRS4 (By similarity). Interacts with INPP5D/SHIP1. Phosphorylated on tyrosine. Phosphorylation is prominent during early development, but decreases at later embryonic stages and in newborn mice. Belongs to the CRK family.