DDB-1 Antibody detects endogenous levels of total DDB-1 protein.

Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to residues near the carboxy terminus of human DDB-1 protein. Antibodies are purified by protein A and peptide affinity chromatography.

Damaged DNA-Binding Protein (DDB) consists of a 127 kDa subunit (DDB-1) and a 48 kDa subunit (DDB-2) that contribute to the formation of the UV-damaged DNA-binding protein complex (UV-DDB) (1-3). In conjunction with CUL4A and ROC-1, the UV-DDB complex forms an E3 ubiquitin ligase that recognizes a broad spectrum of DNA lesions such as cyclobutane pyrimidine dimers, 6-4 photoproducts, apurinic sites and short mismatches. The complex polyubiquitinates components of the nucleotide excision repair pathway (4-6). Loss of DDB activity has been identified in a subset of xeroderma pigmentosum complementation group E (XP-E) patients and has been linked to the deficient repair of cyclobutane pyrimidine dimers in cells derived from these patients (7-10).
DDB-1 is a relatively abundant protein that is vital for normal cell function and is evolutionarily conserved in mammals, insects, worms and plants. Unlike DDB-2, lesions in DDB-1 have yet to be indentified in XP-E patients. In association with ROC-1 and CUL4A, DDB-1 functions to recruit substrate-specific targeting subunits, generally known as DCAFs or CDWs, to CUL4-RING E3 ubiquitin-protein ligase complexes (11,12). Ubiquitination of histone H2A, histone H3 and histone H4 at sites of UV-induced DNA damage by the DDB1-DDB2-CUL4A-ROC1 E3 ubiquitin-protein ligase complex may facilitate their removal from the nucleosome in order to promote DNA repair (13-15). DDB-1, in association with other CUL4-based E3 ligase complexes, has also been found to be a regulator of mTOR signaling (16,17).