Electrophoresis. 2015 Apr;36(7):973-7. doi: 10.1002/elps.201400566. Epub 2015 Mar 24.

Single nucleus versus single-cell gel electrophoresis: kinetics of DNA track formation.

Electrophoresis

Katerina Afanasieva, Marianna Chopei, Andrei Sivolob

PMID: 25631953 DOI: 10.1002/elps.201400566

Abstract

Single-cell gel electrophoresis, or the comet assay, is usually performed with nucleoids prepared after a lysis of either whole cells (more often) or isolated cell nuclei (rarely). Electrophoretic properties of the second type of nucleoids have never been investigated carefully. We measured the kinetics of the DNA exit from nuclei-derived nucleoids in comparison with cell-derived nucleoids. The results show that general organization of the nuclei-derived nucleoids is not changed very much in comparison with nucleoids commonly obtained from whole cells. At the same time, in contrast to the cell-derived nucleoids, for which the exit is stepwise and cooperative, the DNA exit from the nuclei-derived nucleoids can be described by a simple monomolecular kinetics. This difference is probably due to agarose penetration into nuclei (but not into cells) before polymerization of the agarose gel. We suggest that single-nucleus gel electrophoresis may be a way for the comet assay standardization.

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Keywords: Cell nuclei; Chromatin loops; Comet assay; Kinetics

Substances

• DNA

MeSH terms

• Cell Nucleus / genetics*
• Comet Assay / methods*
• DNA / analysis*
• Humans
• Kinetics

Publication Types

• Journal Article