title: Decreased fidelity of DNA polymerase activity isolated from aging human fibroblasts.
abstract: DNA polymerase (deoxynucleosidetriphosphate: DNA nucleotidyltransferase, EC 2.7.7.7 or DNA nucleotidyltransferase) activity, isolated from late and early passage cells of the diploid human fibroblast line, MRC-5, was compared. The level of activity dropped with increasing passage. In addition, when the fidelity of polymerization was monitored with four synthetic templates under a variety of conditions, it was observed that the enzyme from late passage cells was more error-prone. The possible relation of these observations to "senescence" of the fibroblasts is discussed.
mesh_terms: D004254:DNA Nucleotidyltransferases / Q000378:metabolism*; D004261:DNA Replication; D005347:Fibroblasts / Q000201:enzymology; D006801:Humans; D008345:Manganese / Q000494:pharmacology; D013698:Templates, Genetic; D013997:Time Factors
chemical_list: D008345:Manganese; D004254:DNA Nucleotidyltransferases