Figure 3: Yeast linker histone maintains and preserves the higher-order chromatin structure organization during chronological ageing. Yeast mutants lacking the linker histone were subjected to ChCA and were compared to the wild type. Chromatin structure was studied at five time points designated as main during the CLS of yeast cells in SD media. (a) ChCA results quantification-measurement of comet length and calculation of chromatin loop lengths in kilobases. The five studied time points are marked on the growth curve built in the figure. The results are presented as bars showing the mean comet length values ± STDVs. The statistical analyses proved these results as significant * . (b) A model describing changes in the higher-order chromatin organization during chronological ageing. On the time course of the chronological lifespan of yeast cells in minimal media are marked five main time points (diamond shape) and their reference to the CLS phases. Wild type and hho1delta nucleoids are drawn with the hypothetical chromatin loop organization changes during ageing. The lack of the linker histone totally abolishes normal chromatin ageing and thus influences overall cellular behaviour during the process.