Increased frequency of chromatid breaks in lymphocytes of heterozygotes of ataxia telangiectasia after in vitro treatment with caffeine

Pawlak, A.L.; Kotecki, Maciej; Ignatowicz, R

doi:10.1016/0027-5107(90)90057-b

Cited by 7 publications

(1 citation statement)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Despite the necessity of 3'-PG removal prior to DNA repair synthesis, and some prior claims of such removal activities in mammalian cells (18,21,28), no direct demonstration of 3'-PG removal by a mammalian enzyme has ever been reported. Previous claims of such activity have either used poorly characterized substrates or synthetic analogs of 3'-PG.…”

Section: Discussionmentioning

confidence: 99%

Human HeLa cell enzymes that remove phosphoglycolate 3′-end groups from DNA

Winters¹,

Weinfeld²,

Jorgensen³

1992

Nucl Acids Res

View full text Add to dashboard Cite

We have purified three chromatographically distinct human enzyme activities from HeLa cells, that are capable of converting bleomycin-treated DNA into a substrate for E. coli DNA polymerase I. The bleomycin-treated DNA substrate used in this study has been characterized via a 32P-postlabeling assay and shown to contain strand breaks with 3'-phosphoglycolate termini as greater than 95% of the detectable dose-dependent lesions. The purified HeLa cell enzymes were shown to be capable of removing 3'-phosphoglycolates from this substrate. Also 3'-phosphoglycolate removal and nucleotide incorporation were enzyme dependent. In addition, all three Hela cell enzymes have been determined to possess Class II AP endonuclease activity. The enzymes lack 3'----5' exonuclease activity and are, therefore, dissimilar to exonuclease III--an E. coli enzyme that can remove 3'-phosphoglycolate.

show abstract

Section: Discussionmentioning

confidence: 99%