A conserved 5′ to 3′ exonuclease activity in the yeast and human nucleotide excision repair proteins RAD2 and XPG

Yvette Habraken, Patrick Sung, Louise Prakash, Satya Prakash

Research output: Contribution to journalArticle

50 Scopus citations


Saccharomyces cerevisiae RAD2 protein and its human homolog xeroderma pigmentosum group G (XPG) protein function in the incision step of nucleotide excision repair of DNA damaged by ultraviolet light. Both RAD2 and XPG proteins have been shown previously to possess an endonuclease activity. Using DNA substrates labeled at either the 5′ end or 3′ end, we now demonstrate that RAD2 protein also digests both single-stranded and double-stranded DNAs exonucleolytically with a 5′ to 3′ directionality. A 5′ to 3′ exonuclease activity is also present in the XPG protein, indicating evolutionary conservation of this activity. The possible role of RAD2 and XPG 5′ to 3′ exonuclease activity in nucleotide excision repair is discussed.

Original languageEnglish (US)
Pages (from-to)31342-31345
Number of pages4
JournalJournal of Biological Chemistry
Issue number50
StatePublished - Dec 16 1994


ASJC Scopus subject areas

  • Biochemistry

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