Anti-RAD3 antibody

Supplementary info

Activity summary

RAD3 also known as XPD is a DNA helicase enzyme with a mass of approximately 89 kDa. It functions in the unwinding of DNA utilizing ATP to separate double-stranded DNA during the process of nucleotide excision repair. This activity is critical for maintaining the integrity of the genome. RAD3 expression is detected in many tissues with high levels found in liver and brain reflecting the need for effective DNA repair where cells frequently undergo division or encounter genotoxic stress.

Biological function summary

RAD3 plays a substantial role in the repair of DNA damage specifically through its involvement in the transcription factor IIH (TFIIH) complex. TFIIH facilitates both DNA repair and transcription by RNA polymerase II linking DNA damage responses to transcriptional regulation. RAD3's helicase activity is necessary for the opening of damaged DNA sites supporting their subsequent repair. It participates by collaborating with other TFIIH components like ERCC2 and ERCC3 to achieve these cellular processes.

Pathways

RAD3 is central to the nucleotide excision repair (NER) and transcription-coupled repair pathways. These pathways manage the rectification of bulky DNA lesions such as those from ultraviolet light-induced pyrimidine dimers. RAD3 interacts with related proteins like XPB a helicase that also contributes to unwinding DNA during repair and CSA which directs the repair of transcription-blocking lesions. Both pathways ensure that genetic information is continuously transmitted without errors promoting cellular survival and preventing genomic instability.

Associated diseases and disorders

RAD3 is involved in conditions such as xeroderma pigmentosum and trichothiodystrophy. Mutations in the RAD3 gene can lead to defects in the NER pathway resulting in hypersensitivity to UV light and increased cancer risk as seen in xeroderma pigmentosum patients. In trichothiodystrophy a rare disorder characterized by brittle hair intellectual disability and UV sensitivity RAD3 mutations can cause similar disruptions in DNA repair mechanisms. In both conditions the collaboration of RAD3 with proteins such as CSA and CSB is important for preventing disease manifestations related to impaired DNA repair processes.