Interactions of acetylated histones with DNA as revealed by UV laser induced histone-DNA crosslinking.
The interaction of acetylated histones with DNA in chromatin has been studied by UV laser-induced crosslinking histones to DNA. After irradiation of the nuclei, the covalently linked protein-DNA complexes were isolated and the presence of histones in them demonstrated immunochemically. When chromatin from irradiated nuclei was treated with clostripain, which selectively cleaved the N-terminal tails of core histones, no one of them was found covalently linked to DNA, thus showing that crosslinking proceeded solely via the N-terminal regions. However, the crosslinking ability of the laser was preserved both upon physiological acetylation of histones, known to be restricted to the N-terminal tails, and with chemically acetylated chromatin. This finding is direct evidence that the postsynthetic histone acetylation does not release the N-terminal tails from interaction with DNA.
Stefanovsky VYu
Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia.
Dimitrov
S I
SI
Angelov
D
D
Pashev
I G
IG
D000107:Acetylation; D000818:Animals; D002417:Cattle; D002843:Chromatin / Q000187:drug effects / Q000378:metabolism; D003432:Cross-Linking Reagents; D003546:Cysteine Endopeptidases / Q000494:pharmacology; D004247:DNA / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006657:Histones / Q000378:metabolism*; D007834:Lasers; D014466:Ultraviolet Rays
D002843:Chromatin; D003432:Cross-Linking Reagents; D006657:Histones; D004247:DNA; D003546:Cysteine Endopeptidases; C019913:clostripain