An enzyme activity in normal and ataxia telangiectasia cell lines which is involved in the repair of gamma-irradiation-induced DNA damage.
An enzyme that enhances the activity of DNA polymerase I (EC 2.7.7.7) for gamma-irradiated calf thymus DNA was demonstrated in cellular extracts of normal human fibroblasts and lymphoid-cell lines. This enzyme was found to be deficient in all cellular extracts of fibroblasts and lymphoid-cell lines examined from patients with the autosomal recessive disease ataxia telangiectasia. The activity in cellular extracts from normal fibroblasts was removed when heated to 100 degrees C for 2 min or when the assay was performed at 4 degrees C. No significant deficiency in primer-activating enzyme activity was observed in cell-free extracts of lymphoid lines from patients with xeroderma pigmentosum, Huntington's chorea or neurofibromatosis, or from an ataxia telangiectasia heterozygote.
D001260:Ataxia Telangiectasia / Q000201:enzymology*; D002460:Cell Line; D004256:DNA Polymerase I / Q000378:metabolism; D004260:DNA Repair; D005347:Fibroblasts / Q000201:enzymology; D005720:Gamma Rays; D006801:Humans; D006816:Huntington Disease / Q000201:enzymology; D008214:Lymphocytes / Q000201:enzymology; D009456:Neurofibromatosis 1 / Q000201:enzymology; D014983:Xeroderma Pigmentosum / Q000201:enzymology
D004256:DNA Polymerase I