该基因编码的蛋白质是酿酒酵母RAD23（一种参与核苷酸切除修复（NER）的蛋白质）的两个人类同系物之一。这种蛋白被发现是蛋白复合物的一个组成部分，它在体外专门补充着色性干皮病C组（xp-c）细胞提取物的NER缺陷。该蛋白还与3-甲基腺嘌呤-DNA糖基化酶（MPG）的核苷酸切除活性相互作用，并提高其活性，提示其在碱基切除修复中的DNA损伤识别作用。这种蛋白含有一个N端泛素样结构域，据报道与26S蛋白酶体相互作用，因此这种蛋白可能参与细胞中泛素介导的蛋白水解途径。选择性剪接导致编码不同亚型的多个转录变体。
The protein encoded by this gene is one of two human homologs of Saccharomyces cerevisiae Rad23, a protein involved in the nucleotide excision repair (NER). This protein was found to be a component of the protein complex that specifically complements the NER defect of xeroderma pigmentosum group C (XP-c) cell extracts in vitro. This protein was also shown to interact with, and elevate the nucleotide excision activity of 3-methyladenine-DNA glycosylase (MPG), which suggested a role in DNA damage recognition in base excision repair. This protein contains an N-terminal ubiquitin-like domain, which was reported to interact with 26S proteasome, and thus this protein may be involved in the ubiquitin mediated proteolytic pathway in cells. Alternative splicing results in multiple transcript variants encoding distinct isoforms.