Chromatin compactification using a model system of DNA-protein complexes
Chikhirzhina, E.V.; Kostyleva, E.I.; Ramm, E.I.; Vorob'ev, V.I.
Tsitologiia 40(10): 883-888
1998
ISSN/ISBN: 0041-3771 PMID: 9864819 Document Number: 494179
Conformational peculiarities of DNA complexes with histones of the H1 family have been studied by the method of circular dichroism (CD). The H1 histones were isolated from spermatozoa of the sea urchin Strongylocentrotus intermedius, starfish Aphelasterias japonica, and bivalve mollusc Chlamis islandicus and also from the rat thymus. It is shown that these sperm-specific histones do not compact DNA in low ionic strength solution. At physiologic conditions H1 from the sea urchin and starfish sperms compact DNA more intensively than other histones. The H1 from rat thymus has a minimum ability to compact DNA. This histone does not change the structure of DNA double helix. It was supposed that it could be associated with interactions of this histone with DNA in the major groove of its helix. At the same time sperm-specific H1 can interact with DNA not only in the major groove but also in the minor groove, and this induces changes in DNA structure. This DNA-protein interaction is specific for the sperm chromatin and may support the supercompact organization of the sperm chromatin.