title: Impaired repair activity of a truncated DNA polymerase beta protein.
abstract: DNA polymerase beta (polbeta) is an essential enzyme for gap filling synthesis in damaged DNA template involved in base excision repair pathway. A truncated polbeta protein is expressed in primary colorectal and breast adenocarcinomas. To determine a possible alteration in the functions of the enzyme, a human cell line named HeLapolbetadelta expressing the truncated form of polbeta has been established. These cells revealed a significantly reduced level of repair activity evaluated by gap filling synthesis and polbeta activity. More importantly, the HeLapolbetadelta cells are hypersensitive to MNNG, a DNA alkylating agent. It appears from the responses that the gap filling synthesis of WT cells, a HeLa cell line overexpressing wild-type polbeta protein, was inhibited by HeLapolbetadelta protein.
authors.affiliation: Department of Cancer Biology, Lerner Research Institute, The Cleveland Clinic Foundation, OH 44195, USA.
authors.forename: N
authors.initials: N
authors.lastname: Bhattacharyya
authors.forename: T
authors.initials: T
authors.lastname: Banerjee
authors.forename: U
authors.initials: U
authors.lastname: Patel
authors.forename: S
authors.initials: S
authors.lastname: Banerjee
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D011088:DNA Ligases; D019951:DNA Polymerase beta / Q000378:metabolism*; D004260:DNA Repair; D004305:Dose-Response Relationship, Drug; D006367:HeLa Cells / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D013997:Time Factors
chemical_list: D008769:Methylnitronitrosoguanidine; D019951:DNA Polymerase beta; D011088:DNA Ligases