The Effect of Oncomutations and Posttranslational Modifications of Histone H1 on Chromatosome Structure and Stability

Abstract

The stability of chromatosome when introducing posttranslational modifications and mutations observed in the case of oncological diseases into the structure of the linker histone was studied using bioinformatics analysis. The chromatosome is formed under the interaction of the nucleosome with the linker histone. This interaction can be characterized by the binding free energy. We hypothesized that oncomutations and posttranslational modifications of the linker histone are associated with a change in its free energy of binding to the nucleosome, and it probably leads to a change in chromatin compaction, thus affecting gene expression. Calculations of the binding free energy were performed using algorithms of the FoldX program. Screening of positions of posttranslational modifications in the linker histone for the presence of steric constraints was also performed. The analysis of the obtained data allowed for the identification of oncomutations and posttranslational modifications that significantly change the binding free energy of the linker histone with the nucleosome, thereby probably affecting the structure of the entire chromatin.