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Histone chaperones regulate histone exchange during transcription.

ABSTRACT: Transcription by RNA polymerase II is accompanied by dynamic changes in chromatin, including the eviction/deposition of nucleosomes or the covalent modification of histone subunits. This study examined the role of the histone H3/H4 chaperones, Asf1 and HIR, in histone mobility during transcription, with particular focus on the histone exchange pathway, using a dual histone expression system. The results showed that the exchange of H3/H4 normally occurs during transcription by the histone chaperones. Both Asf1 and HIR are important for histone deposition but have a different effect on histone exchange. While Asf1 mediated incorporation of external H3/H4 and renewal of pre-existing histones, HIR opposed it. The balance of two opposing activities might be an important mechanism for determining current chromatin states.

SUBMITTER: Kim HJ

PROVIDER: S-EPMC2063486 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Histone chaperones regulate histone exchange during transcription.

Kim Hye-Jin HJ Seol Ja-Hwan JH Han Jeung-Whan JW Youn Hong-Duk HD Cho Eun-Jung EJ

The EMBO journal 20071004 21

Transcription by RNA polymerase II is accompanied by dynamic changes in chromatin, including the eviction/deposition of nucleosomes or the covalent modification of histone subunits. This study examined the role of the histone H3/H4 chaperones, Asf1 and HIR, in histone mobility during transcription, with particular focus on the histone exchange pathway, using a dual histone expression system. The results showed that the exchange of H3/H4 normally occurs during transcription by the histone chapero ...[more]

PMID: 17914459

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