Regulation of repair by the 26Sproteasome

[摘要] Cellular processes such as transcription and DNA repair may beregulated through diverse mechanisms, including RNA synthesis,protein synthesis, posttranslational modification and proteindegradation. The 26Sproteasome, which is responsible fordegrading a broad spectrum of proteins, has been shown tointeract with several nucleotide excision repair proteins,including xeroderma pigmentosum B protein (XPB), Rad4, and Rad23.Rad4 and Rad23 form a complex that binds preferentially toUV-damaged DNA. The 26Sproteasome may regulate repair bydegrading DNA repair proteins after repair is completed or,alternatively, the proteasome may act as a molecular chaperone topromote disassembly of the repair complex. In either case, theinteraction between the proteasome and nucleotide excision repairdepends on proteins like Rad23 that bind ubiquitin-conjugatedproteins and the proteasome. While the iteration between Rad4 andRad23 is well established, it will be interesting to determinewhat other proteins are regulated in a Rad23-dependent manner.

[学科分类] 基础医学