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Progressive methylation of ageing histones by Dot1 functions as a timer.

ABSTRACT: Post-translational modifications of histone proteins have a crucial role in regulating gene expression. If efficiently re-established after chromosome duplication, histone modifications could help propagate gene expression patterns in dividing cells by epigenetic mechanisms. We used an integrated approach to investigate the dynamics of the conserved methylation of histone H3 Lys 79 (H3K79) by Dot1. Our results show that methylation of H3K79 progressively changes after histone deposition, which is incompatible with a rapid copy mechanism. Instead, methylation accumulates on ageing histones, providing the cell with a timer mechanism to directly couple cell-cycle length to changes in chromatin modification on the nucleosome core.

SUBMITTER: De Vos D

PROVIDER: S-EPMC3166457 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Progressive methylation of ageing histones by Dot1 functions as a timer.

De Vos Dirk D Frederiks Floor F Terweij Marit M van Welsem Tibor T Verzijlbergen Kitty F KF Iachina Ekaterina E de Graaf Erik L EL Altelaar A F Maarten AF Oudgenoeg Gideon G Heck Albert J R AJ Krijgsveld Jeroen J Bakker Barbara M BM van Leeuwen Fred F

EMBO reports 20110901 9

Post-translational modifications of histone proteins have a crucial role in regulating gene expression. If efficiently re-established after chromosome duplication, histone modifications could help propagate gene expression patterns in dividing cells by epigenetic mechanisms. We used an integrated approach to investigate the dynamics of the conserved methylation of histone H3 Lys 79 (H3K79) by Dot1. Our results show that methylation of H3K79 progressively changes after histone deposition, which i ...[more]

PMID: 21760613

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