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PubMed · 7973637

DNA loop repair by human cell extracts.

A Umar·J C Boyer·T A Kunkel
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Abstract

An activity in human cell extracts is described that repairs DNA with loops of five or more unpaired bases. Repair is strand-specific and is directed by a nick located 5' or 3' to the loop. This repair is observed in a colorectal cancer cell line that is devoid of a wild-type hMLH1 gene and is deficient in repair of mismatches. However, a cell line with deletions in both hMSH2 alleles is deficient in repair of both loops and mismatches. Defects in loop repair may be relevant to the repetitive-sequence instability observed in cancers and other hereditary diseases.

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Adaptor Proteins, Signal TransducingBase CompositionBase SequenceCarrier ProteinsCell ExtractsCell LineColorectal NeoplasmsDNA RepairDNA, SatelliteDNA-Binding ProteinsHeLa CellsHumansMolecular Sequence DataMutL Protein Homolog 1MutS Homolog 2 ProteinNeoplasm ProteinsNuclear ProteinsNucleic Acid HeteroduplexesProto-Oncogene ProteinsRepetitive Sequences, Nucleic AcidTumor Cells, CulturedJournal Article

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A Umar, J C Boyer, T A Kunkel. 1994-11-04. DNA loop repair by human cell extracts.. https://doi.org/10.1126/science.7973637

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