Effect of treatment with Triton X-100 on DNA integrity and DNA:RNA: protein ratio of rat liver nuclei
Carlo, P.; Martelli, A.; Bignone, F.A.
Bollettino della Societa Italiana di Biologia Sperimentale 57(22): 2203-2208
1981
ISSN/ISBN: 0037-8771 PMID: 6173047 Document Number: 178864
A procedure is described that gives clean nuclei with intact DNA from a rat liver cell suspension. Cytoplasmic contamination is removed by successive treatments with a non ionic detergent, Triton X-100 (0.75%, v/v). We found that with ratios DNA:RNA: protein of 1:0.09:3.29 (2 Triton X-100 steps) the integrity of DNA is preserved: further decrease in RNA and protein content (3 Triton X-100 steps) causes DNA breakage, probably because of extraction of nuclear proteins. In order to estimate DNA integrity, its viscosity was determined by the use of a new oscillating crucible viscometer; this method makes possible the evaluation of extremely small levels of DNA damage as that induced by 0.067 mg/kg of DMNA injected i.p.