APE1 is the major 3'-phosphoglycolate activity in human cell extracts.
نویسندگان
چکیده
DNA strand breaks containing 3'-phosphoglycolate (3'-PG) ends are the major lesions induced by ionizing radiation. The repair of this lesion is not completely understood and several activities are thought to be involved in processing of 3'-PG ends. In this study we examined activities in human whole cell extracts (WCE) responsible for removal of 3'-PG. Using a radiolabelled oligonucleotide containing a single nucleotide gap with internal 5'-phosphate and 3'-PG ends, we demonstrate that the major 3'-PG activity in human WCE is Mg2+ dependent and that this activity co-purifies with AP endonuclease 1 (APE1) over phosphocellulose and gel filtration chromatography. Furthermore, immunodepletion of APE1 from active gel filtration fractions using APE1 specific antibodies reveals that the major activity against 3'-PG in human WCE is APE1.
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عنوان ژورنال:
- Nucleic acids research
دوره 32 12 شماره
صفحات -
تاریخ انتشار 2004