DDB1
Required for DNA repair. Binds to DDB2 to form the UV-damaged DNA-binding protein complex (the UV-DDB complex). The UV-DDB complex may recognize 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 appears to function as a component of numerous distinct DCX (DDB1-CUL4-X-box) E3 ubiquitin-protein ligase complexes which mediate the ubiquitination and subsequent proteasomal degradation of target proteins. The functional specificity of the DCX E3 ubiquitin-protein ligase complex is determined by the variable substrate recognition component recruited by DDB1. DCX(DDB2) (also known as DDB1-CUL4-ROC1, CUL4-DDB-ROC1 and CUL4-DDB-RBX1) 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. DCX(DDB2) also ubiquitinates XPC, which may enhance DNA-binding by XPC and promote NER. DCX(DTL) plays a role in PCNA-dependent polyubiquitination of CDT1 and MDM2-dependent ubiquitination of TP53 in response to radiation-induced DNA damage and during DNA replication. DCX(ERCC8) (the CSA complex) plays a role in transcription-coupled repair (TCR). May also play a role in ubiquitination of CDKN1B/p27kip when associated with CUL4 and SKP2. The DDB1-CUL4A-DTL E3 ligase complex regulates the circadian clock function by mediating the ubiquitination and degradation of CRY1. DDB1-mediated CRY1 degradation promotes FOXO1 protein stability and FOXO1-mediated gluconeogenesis in the liver. Belongs to the DDB1 family. 2 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Molecular Function: cullin family protein binding; damaged DNA binding; DNA binding; protein binding; protein-containing complex binding; protein-macromolecule adaptor activity; ubiquitin ligase complex scaffold activity; WD40-repeat domain binding
Biological Process: apoptotic process; biological process involved in interaction with symbiont; cellular response to UV; DNA damage response; DNA repair; ectopic germ cell programmed cell death; epigenetic programming in the zygotic pronuclei; negative regulation of apoptotic process; negative regulation of developmental process; negative regulation of reproductive process; nucleotide-excision repair; positive regulation by virus of viral protein levels in host cell; positive regulation of gluconeogenesis; positive regulation of protein catabolic process; positive regulation of viral genome replication; proteasomal protein catabolic process; proteasome-mediated ubiquitin-dependent protein catabolic process; protein ubiquitination; regulation of circadian rhythm; regulation of mitotic cell cycle phase transition; rhythmic process; spindle assembly involved in female meiosis; ubiquitin-dependent protein catabolic process; UV-damage excision repair; viral release from host cell; Wnt signaling pathway
Alt. Names/Synonyms: damage specific DNA binding protein 1; damage-specific DNA binding protein 1, 127kDa; Damage-specific DNA-binding protein 1; DDB p127 subunit; DDB1; DDBa; DNA damage-binding protein 1; DNA damage-binding protein a; HBV X-associated protein 1; UV-damaged DNA-binding factor; UV-damaged DNA-binding protein 1; UV-DDB 1; UV-DDB1; XAP-1; XAP1; Xeroderma pigmentosum group E-complementing protein; XPCe; XPE; XPE-BF; XPE-binding factor
