DNA damage binding protein

DNA damage-binding protein or UV-DDB is a protein complex that is responsible for repair of UV-damaged DNA. This complex is composed of two protein subunits, a large subunit DDB1 (p127) and a small subunit DDB2 (p48). When cells are exposed to UV radiation, DDB1 moves from the cytosol to the nucleus and binds to DDB2, thus forming the UV-DDB complex. This complex functions in nucleotide excision repair, recognising UV-induced (6-4) pyrimidine-pyrimidone photoproducts and cyclobutane pyrimidine dimers.