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6nj9 is a 12 chain structure with sequence from [1], African clawed frog and Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[H32_XENLA] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. [H2B11_XENLA] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. [H2A1_XENLA] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. [H4_XENLA] Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. [DOT1L_HUMAN] Histone methyltransferase. Methylates 'Lys-79' of histone H3. Nucleosomes are preferred as substrate compared to free histones. Binds to DNA.
Publication Abstract from PubMed
Methylation of histone H3 K79 by Dot1L is a hallmark of actively transcribed genes that depends on monoubiquitination of H2B K120 (H2B-Ub) and is an example of histone modification cross-talk that is conserved from yeast to humans. We report here cryo-EM structures of Dot1L bound to ubiquitinated nucleosome that show how H2B-Ub stimulates Dot1L activity and reveal a role for the histone H4 tail in positioning Dot1L. We find that contacts mediated by Dot1L and the H4 tail induce a conformational change in the globular core of histone H3 that reorients K79 from an inaccessible position, thus enabling this side chain to insert into the active site in a position primed for catalysis. Our study provides a comprehensive mechanism of cross-talk between histone ubiquitination and methylation and reveals structural plasticity in histones that makes it possible for histone-modifying enzymes to access residues within the nucleosome core.
Mechanism of Cross-talk between H2B Ubiquitination and H3 Methylation by Dot1L.,Worden EJ, Hoffmann NA, Hicks CW, Wolberger C Cell. 2019 Feb 8. pii: S0092-8674(19)30151-5. doi: 10.1016/j.cell.2019.02.002. PMID:30765112[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Worden EJ, Hoffmann NA, Hicks CW, Wolberger C. Mechanism of Cross-talk between H2B Ubiquitination and H3 Methylation by Dot1L. Cell. 2019 Feb 8. pii: S0092-8674(19)30151-5. doi: 10.1016/j.cell.2019.02.002. PMID:30765112 doi:http://dx.doi.org/10.1016/j.cell.2019.02.002
