Assays, repair

The ReProComet assay (repair-proficient comet assay) was developed to detect chemically induced DNA damage in sperm cells. In order to overcome the intrinsic DNA repair deficiency of the sperm cells this modified comet assay is based on the addition of a protein extract from HeLa cells to agarose-embedded sperm on microscopic slides previously exposed to mutagenic compounds. A clear-cut dose-dependent effect was measured after addition of the cell extract representing a proof of concept of a novel in vitro mutagenicity test on sperm [18]. Transferability to other laboratories remains to be addressed. 

Reversion Mutation Assays Forward Mutation Assays Repair Tests... 

Mouse visible or eleetrophoretie specifie-locus tests Assays for skeletal and cataract mutations Cytogenetic analy.sis and heritable translocation assays DNA damage and repair in rodent germ cells Dominant lethal assay... 

Gasiorowski, K., Brocos, B. DNA repair of hydrogen peroxide-induced damage in human lymphocytes in the presence of four antimutagens. A study with alkaline single cell gel electrophoresis (comet assay). Cellular Molecular Biology Letters, Vol.6, (2001), pp. 897-911, ISSN 1425-8153... 

Doolittle DJ, Muller G, Scribner HE. 1987. The in vivo-in vitro hepatocyte assay for assessing DNA repair and DNA replication Studies in the CD-I mouse. Food Chem Toxicol 25 399-405. 

Shimada T, Swanson AF, Leber P, et al. 1985. Activities of chlorinated ethane and ethylene compounds in the Salmonella microsome mutagenesis and rat hepatocyte/DNA repair assays under vapor phase exposure conditions. Cell Biol Toxicol 1 159-179. 

Eukaryotic organisms Mammalian cells Rat hepatocytes (DNA-repair Assay) DNA damage No data Ciba-Geigy 1984c Reolube HYD 46... 

Scheme 5b, solutions (pH=7.5) of these DNA strands were subsequently irradiated under anaerobic conditions, after reduction of the flavin with sodium dithionite [51]. HPLC analysis of samples removed from the assay solution during such an irradiation experiment showed clean transformation of the Tf=T-containing DNA strands into the repaired TfT-containing DNA strands (Fig. 2). These experiments showed for the first time that a reduced flavin, if incorporated into DNA, can inject an extra electron into a DNA du-...

Overall, it can be envisioned that the Py-G group 47 represents an important label for the time-resolved studies of DNA dynamics and stacking interaction [123] and could be applied especially for assays in which conformational changes or base-flipping processes are essential in observation, such as in the investigation of DNA-protein complexes with DNA repair proteins. 

Collins, A. R. (2004). The COMET assay for DNA damage and repair. Molecular... 

There was no increase in mutation frequency at the hypoxanthine-guanine phosphoribosyl transferase gene locus in the presence or absence of S9 (Bootman et al. 1988b), and results were negative in a DNA repair assay with E. coli (Hodson-Walker and May 1988). 

Assays for DNA Effects DNA damage and repair unscheduled DNA synthesis in vitro / ... 

The Polymerase Chain Reaction. In the past, a major drawback of hybridization assays was their need for relatively large amounts of sample DNA to compensate for their low sensitivity. This problem has been surmounted in recent years by the development of powerful enzymatic techniques that can exponentially replicate specific DNA sequences in the test tube. With these techniques it is now possible to analyze vanishingly small samples that initially contain fewer than 10 copies of the sequence of interest. The new methods take advantage of the chemical properties of nucleic acids and of highly specialized enzymes that can repair and replicate DNA in vitro. 

Olive, P.L., Banath, J.P., and Durand, R.E., Heterogeneity in radiation-induced DNA damage and repair in tumor and normal cells measured using the "comet" assay, Radiat. Res., 122, 86, 1990. 

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