30 nm chromatin fibre decompaction requires both H4-K16 acetylation and linker histone eviction.
The mechanism by which chromatin is decondensed to permit access to DNA is largely unknown. Here, using a model nucleosome array reconstituted from recombinant histone octamers, we have defined the relative contribution of the individual histone octamer N-terminal tails as well as the effect of a targeted histone tail acetylation on the compaction state of the 30 nm chromatin fiber. This study goes beyond previous studies as it is based on a nucleosome array that is very long (61 nucleosomes) and contains a stoichiometric concentration of bound linker histone, which is essential for the formation of the 30 nm chromatin fiber. We find that compaction is regulated in two steps: Introduction of H4 acetylated to 30% on K16 inhibits compaction to a greater degree than deletion of the H4 N-terminal tail. Further decompaction is achieved by removal of the linker histone.
Robinson
Philip J J
PJ
MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK.
An
Woojin
W
Routh
Andrew
A
Martino
Fabrizio
F
Chapman
Lynda
L
Roeder
Robert G
RG
Rhodes
Daniela
D
D000107:Acetylation; D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D002843:Chromatin / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster; D006657:Histones / Q000737:chemistry / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism*; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D011994:Recombinant Proteins / Q000378:metabolism; D017384:Sequence Deletion; D014981:Xenopus
D002843:Chromatin; D006657:Histones; D009707:Nucleosomes; D011994:Recombinant Proteins; D008239:Lysine