Linker histones H1 in human disease

Linker histones (H1) are basic proteins that are part of the nucleosome structure in the cell nucleus and are involved in the packaging of genetic material and the regulation of gene expression. As research progressed, it was discovered that linker histones constitute the largest group of histones in terms of variants found in humans. Even though the H1 variants differ slightly in the primary structure, they can perform different functions, undergo multiple post-translational modifications and differ in cellular localization. In addition to the nucleus, histones H1 can occur in the cytoplasm, on the cell surface and in the intercellular space. In these places, they play a supporting role for the immune system and act as signaling molecules. Changes in the levels of histones and their post-translational modifications have been associated with many human diseases and it is postulated that some of them may serve as biomarkers or therapeutic targets.