[Histone H1 – structure and function].

Linker histones (H1) are proteins found in the nuclei of the vast majority of Eucaryota, playing important roles in their life and development. H1 takes part in processes such as chromatin condensation, transcriptional regulation of gene expression, apoptosis induction and many more. Despite its common presence and essential function, many questions remain unanswered. Experiments conducted to date don’t provide unambiguous information on such crucial issues as e.g. the way linker histones bind to nucleosome. There is also much surprising information about H1 participating in physiological processes not connected directly to its widely known function – e.g. providing a microtubule organization center in plants or contributing to the defense against pathogens in fish. The objective of the present work is to provide insights into many aspects of linker histone structure and function, collect and systematize current knowledge and to outline questions worth answering in the future.