title: Modulation of the higher-order folding of chromatin by deletion of histone H3 and H4 terminal domains.
abstract: The 'tails' of histones H3 and H4 were removed by light in situ trypsin digestion of the nuclei. The alterations in the higher-order folding of chromatin resulting from this treatment were monitored by ethidium bromide titration. We found that DNA-intercalation of ethidium bromide under these conditions exhibited a complex concentration effect that was dependent on the extent of chromatin folding. This most likely reflects the structural transitions of chromatin during its folding as a result of the changes in the nucleosome linker twist [Woodcock, Grigoryev, Horowitz and Whitaker (1993) Proc. Natl. Acad. Sci. U.S.A. 90, 9021-9025]. These results strongly suggest that the H3 and H4 terminal domains play a very important role in chromatin folding. We discuss the molecular basis of this phenomenon and propose a novel generalized model for the higher-order folding of chromatin.
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, BC, Canada.
authors.forename: W A
authors.initials: WA
authors.lastname: Krajewski
authors.forename: J
authors.initials: J
authors.lastname: Ausió
mesh_terms: D002467:Cell Nucleus / Q000737:chemistry; D002843:Chromatin / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004996:Ethidium / Q000494:pharmacology; D006367:HeLa Cells; D006657:Histones / Q000737:chemistry*; D006801:Humans; D007364:Intercalating Agents / Q000494:pharmacology; D008836:Micrococcal Nuclease / Q000378:metabolism; D009690:Nucleic Acid Conformation; D009707:Nucleosomes / Q000737:chemistry; D017510:Protein Folding; D014357:Trypsin / Q000378:metabolism
chemical_list: D002843:Chromatin; D006657:Histones; D007364:Intercalating Agents; D009707:Nucleosomes; D004247:DNA; D008836:Micrococcal Nuclease; D014357:Trypsin; D004996:Ethidium