Biopolymers and cell. 2010; 26 (5): 351-359
Nucleosome conformational flexibility in experiments with single chromatin fibers
A. V. Sivolob
Taras Shevchenko National University of Kyiv; 64, Volodymyrska Str, Kyiv, Ukraine, 01033
Studies on the chromatin nucleosome organization play an ever increasing role in our comprehension of mechanisms of the gene activity regulation. This minireview describes the results on the nucleosome conformational flexibility, which were obtained using magnetic tweezers to apply torsion to oligonucleosome fibers reconstituted on single DNA molecules. Such an approach revealed a new structural form of the nucleosome, the reversome, in which DNA is wrapped in a right-handed superhelix around a distorted histone octamer. Molecular mechanisms of the nucleosome structural flexibility and its biological relevance are discussed.
Keywords: nucleosome, DNA supercoiling, chromatin fiber, conformational flexibility.