Fyn-related kinase (FRK, formerly tyrosine protein kinase 5) is an enzyme that in humans is encoded by the FRK gene.[5][6]
The protein encoded by this gene belongs to the TYR family of protein kinases. This tyrosine kinase is a nuclear protein and may function during G1 and S phase of the cell cycle and suppress growth.[6]
FRK has been shown to interact with retinoblastoma protein.[7]