Proteasome Involvement in the Repair of DNA Double-Strand Breaks
Michael-Christopher Keogh2004, Molecular Cell
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Abstract
The 26S proteasome, which consists of a 19S regula-1 Kings College Circle Toronto, Ontario M5S 1A8 tory cap and 20S catalytic core, degrades polyubiquitinated proteins in eukaryotic cells (Voges et al., 1999). Canada 3 Department of Biological Chemistry In addition to directing ubiquitin-dependent proteolysis, the proteasome has been shown to have nonproteolytic and Molecular Pharmacology Harvard Medical School roles in recent studies (Voges et al., 1999). Although no direct link between the proteasome and the repair of Boston, Massachusetts 02115 DNA DSBs has been reported, recent work has suggested a role for the 19S proteasome in nucleotide excision repair (NER) mediated by the repair protein Rad23 Summary (Russell et al., 1999a; Schauber et al., 1998). Russell et al. (1999a) further demonstrated that the 19S protea-Affinity purification of the yeast 19S proteasome resome, but not the 20S core, functions in NER and that vealed the presence of Sem1 as a subunit. Its human this process is independent of proteolysis. Furthermore, homolog, DSS1, was found likewise to copurify with the 19S proteasome has been shown to have not only the human 19S proteasome. DSS1 is known to associa stimulatory role in NER, but a negative role as well ate with the tumor suppressor protein BRCA2 involved which is mediated by Rad23 (Gillette et al.
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