A positive role for histone acetylation in transcription factor access to nucleosomal DNA.
Acetylation of the N-terminal tails of the core histones directly facilitates the recognition by TFIIIA of the 5S RNA gene within model chromatin templates. This effect is independent of a reduction in the extent of histone-DNA interactions or a change in DNA helical repeat; it is also independent of whether a histone tetramer or octamer inhibits TFIIIA binding. Removal of the N-terminal tails from the core histones also facilitates the association of TFIIIA with nucleosomal templates. We suggest that the histone tails have a major role in restricting transcription factor access to DNA and that their acetylation releases this restriction by directing dissociation of the tails from DNA and/or inducing a change in DNA configuration on the histone core to allow transcription factor binding. Acetylation of core histones might be expected to exert a major influence on the accessibility of chromatin to regulatory molecules.
Lee
D Y
DY
Laboratory of Molecular Embryology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892.
Hayes
J J
JJ
Pruss
D
D
Wolffe
A P
AP
D000107:Acetylation; D000818:Animals; D002645:Chickens; D004275:DNA, Ribosomal / Q000378:metabolism*; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism*; D006801:Humans; D009707:Nucleosomes / Q000378:metabolism*; D012341:RNA, Ribosomal, 5S / Q000235:genetics*; D035561:Transcription Factor TFIIA; D014157:Transcription Factors / Q000378:metabolism*; D014981:Xenopus; D014982:Xenopus laevis
D004275:DNA, Ribosomal; D006657:Histones; D009707:Nucleosomes; D012341:RNA, Ribosomal, 5S; D035561:Transcription Factor TFIIA; D014157:Transcription Factors