XPA : XPA, DNA damage recognition and repair factor
Description
The XPA (XPA, DNA damage recognition and repair factor) is a protein-coding gene located on chromosome 9.
The XPA gene provides instructions for making a protein that is essential for repairing damaged DNA. DNA damage can be caused by various factors including ultraviolet (UV) rays from sunlight, toxic chemicals, radiation, and unstable molecules called free radicals. While DNA damage is frequent, normal cells typically repair it before it causes issues. A major DNA repair mechanism is known as nucleotide excision repair (NER). Within this process, the XPA protein helps to identify DNA damage and stabilize the DNA as it is being repaired. XPA attaches to damaged DNA segments, interacting with numerous other proteins within a large complex. This complex unwinds the damaged section of DNA, removes (excises) the damaged portion, and replaces it with the correct DNA sequence.
XPA plays a key role in DNA excision repair, initiating the process by binding to damaged sites. Its affinity for these sites varies depending on the type of damage and the DNA's transcriptional activity. XPA is essential for the phosphorylation of CHEK1 by UV radiation and the recruitment of CEP164 to cyclobutane pyrimidine dimmers (CPDs), which are DNA lesions caused by UV exposure.
XPA is also known as XP1, XPAC.
