Cytophotometric determination of unscheduled DNA synthesis

✍ Scribed by Kallol K. Bose; Dr. David C. Allison

• Book ID: 102813630
• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 654 KB
• Volume: 8
• Category: Article
• ISSN: 0196-4763
• DOI: 10.1002/cyto.990080214

✦ Synopsis

We describe a cytophotometric assay for unscheduled DNA synthesis (UDS) in asynchronously growing cells. Monolayer cultures of human HEp-2 and mouse MCa-11 cells were incubated with the carcinogen methylmethane sulfonate (MMS), as well as with hydroxyurea and (3H)thymidine. Slides were prepared, and the DNA contents and areas of nuclei were measured by absorption cytophotometry. The labeling of the nuclei, determined on the basis of their DNA content to be in GOIG1, was selectively measured after the preparation of autoradiographs. The labeling of the GO/G1 cells increased with increasing doses of MMS. We also found that the increased nuclear labeling after MMS treatment was not due to induction of replicative DNA synthesis or selective destruction of GO/ G1 cells. The results of this assay compared favorably with a standard biochemical method for measuring unscheduled DNA synthesis by benzoylated naphthoylated DEAE cellulose chromatography.