Protein, which is both involved in DNA repair and protein ubiquitination, as part of the UV-DDB complex and DCX (DDB1-CUL4-X-box) complexes, respectively. Core component of the UV-DDB complex (UV-damaged DNA-binding protein complex), a complex that recognizes UV-induced DNA damage and recruit proteins of the nucleotide excision repair pathway (the NER pathway) to initiate DNA repair. The UV-DDB complex preferentially binds to cyclobutane pyrimidine dimers (CPD), 6-4 photoproducts (6-4 PP), apurinic sites and short mismatches. Also functions as the substrate recognition module for the DCX (DDB2-CUL4-X-box) E3 ubiquitin-protein ligase complex DDB2-CUL4-ROC1 (also known as CUL4-DDB-ROC1 and CUL4-DDB-RBX1). The DDB2-CUL4-ROC1 complex may ubiquitinate histone H2A, histone H3 and histone H4 at sites of UV-induced DNA damage. The ubiquitination of histones may facilitate their removal from the nucleosome and promote subsequent DNA repair. Protein modification; protein ubiquitination. Component of the UV-DDB complex which includes ddb1 and ddb2 (PubMed:19109893). Component of a DCX (DDB1-CUL4-X-box) E3 ubiquitin-protein ligase complex that includes cul4a, or cul4b, ddb1, ddb2 and rbx1 (PubMed:22118460). A large number of other DCX complexes may also exist in which an alternate substrate targeting subunit replaces ddb2. These targeting subunits are generally known as DCAF (ddb1- and cul4-associated factor) or CDW (cul4-ddb1-associated WD40-repeat) proteins (By similarity). Accumulates at sites of DNA damage following UV irradiation. The DWD box is required for interaction with ddb1. Interblade loops of the WD repeat region mediate most of the interaction with DNA. A hairpin between blades 5 and 6 inserts into DNA minor groove and mediates recognition of lesions and separation of the damaged and undamaged strands. Belongs to the WD repeat DDB2/WDR76 family.