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30 nm chromatin fibre decompaction requires both H4-K16 acetylation and linker histone eviction.

ABSTRACT: 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.

SUBMITTER: Robinson PJ

PROVIDER: S-EPMC3870898 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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30 nm chromatin fibre decompaction requires both H4-K16 acetylation and linker histone eviction.

Robinson Philip J J PJ An Woojin W Routh Andrew A Martino Fabrizio F Chapman Lynda L Roeder Robert G RG Rhodes Daniela D

Journal of molecular biology 20080429 4

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) an ...[more]

PMID: 18653199

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