title: Study of gene-specific DNA repair in the comet assay with padlock probes and rolling circle amplification.
abstract: We used padlock probes to study the rate of gene specific repair of three genes, OGG1 (8-oxoguanine-DNA glycosylase-1), XPD (xeroderma pigmentosum group D), and HPRT (hypoxanthine-guanine phosphoribosyltransferase) in human lymphocytes, in relation to the repair rate of Alu repeats and total genomic DNA. Padlock probes offer highly specific detection of short target sequences by combining detection by ligation and signal amplification. In this approach only genes in sequences containing strand breaks, which become single-stranded in the tail, are available for hybridisation. Thus the total number of signals from the padlock probes per comet gives a direct measure of the amount of damage (strand-breaks) present and allows the repair process to be monitored. This method could provide insights on the organisation of genomic DNA in the comet tail. Alu repeat containing DNA was repaired rapidly in comparison with total genomic DNA, and the studied genes were generally repaired more rapidly than the Alu repeats.
authors.affiliation: Department of Genetics and Pathology, Rudbeck Laboratory, Uppsala University, SE-75185 Uppsala, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Henriksson
authors.forename: Sergey
authors.initials: S
authors.lastname: Shaposhnikov
authors.forename: Mats
authors.initials: M
authors.lastname: Nilsson
authors.forename: Andrew
authors.initials: A
authors.lastname: Collins
mesh_terms: D020552:Comet Assay / Q000379:methods; D004249:DNA Damage; D045647:DNA Glycosylases / Q000235:genetics / Q000502:physiology*; D015342:DNA Probes / Q000235:genetics / Q000502:physiology; D004260:DNA Repair; D004277:DNA, Single-Stranded / Q000235:genetics / Q000502:physiology; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics / Q000502:physiology*; D008856:Microscopy, Fluorescence; D051759:Xeroderma Pigmentosum Group D Protein / Q000235:genetics / Q000502:physiology*
chemical_list: D015342:DNA Probes; D004277:DNA, Single-Stranded; D007041:Hypoxanthine Phosphoribosyltransferase; D045647:DNA Glycosylases; C479058:oxoguanine glycosylase 1, human; D051759:Xeroderma Pigmentosum Group D Protein; C497292:ERCC2 protein, human