scholarly journals Structural basis for activation of Dot1L methyltransferase on the nucleosome by histone H2BK120 ubiquitylation

2018 ◽  
Author(s):  
Cathy J Anderson ◽  
Matthew R Baird ◽  
Allen Hsu ◽  
Emily H Barbour ◽  
Yuka Koyama ◽  
...  
Keyword(s):  
Histone H3 ◽  
Point Mutations ◽  
Leukemia Cells ◽  
Structural Basis ◽  
Histone H2b ◽  
Optimal Activity ◽  
A Site ◽  
H3k79 Methylation

Histone H3 lysine 79 (H3K79) methylation is enriched on actively transcribed genes, and its misregulation is a hallmark of leukemia. Methylation of H3K79, which resides on the structured disk face of the nucleosome, is mediated by the Dot1L methyltransferase. Dot1L activity is part of a trans-histone crosstalk pathway, requiring prior histone H2B ubiquitylation of lysine 120 (H2BK120ub) for optimal activity. However, the molecular details describing both how Dot1L binds to the nucleosome and why Dot1L is activated by H2BK120 ubiquitylation are unknown. Here we present the cryo-EM structure of Dot1L bound to a nucleosome reconstituted with a site-specifically ubiquitylated H2BK120. The structure reveals that Dot1L engages the nucleosome acidic patch using an arginine anchor and occupies a conformation poised for methylation. Ubiquitin directly interacts with Dot1L and is positioned as a clamp on the nucleosome interacting region of Dot1L. Using our structure, we identify point mutations that disrupt the nucleosome-specific and ubiquitin-dependent activities of Dot1L. This study establishes a path to better understand Dot1L function in normal and leukemia cells.

scholarly journals Regulation of the Dot1 histone H3K79 methyltransferase by histone H4K16 acetylation

Science ◽  
2021 ◽  
Vol 371 (6527) ◽  
pp. eabc6663
Author(s):  
Marco Igor Valencia-Sánchez ◽  
Pablo De Ioannes ◽  
Miao Wang ◽  
David M. Truong ◽  
Rachel Lee ◽  
...  
Keyword(s):  
Histone H3 ◽  
Histone H4 ◽  
Histone H2b ◽  
Epigenetic State ◽  
Optimal Maintenance ◽  
H4k16 Acetylation ◽  
H3k79 Methylation ◽  
Regulate Gene

Dot1 (disruptor of telomeric silencing-1), the histone H3 lysine 79 (H3K79) methyltransferase, is conserved throughout evolution, and its deregulation is found in human leukemias. Here, we provide evidence that acetylation of histone H4 allosterically stimulates yeast Dot1 in a manner distinct from but coordinating with histone H2B ubiquitination (H2BUb). We further demonstrate that this stimulatory effect is specific to acetylation of lysine 16 (H4K16ac), a modification central to chromatin structure. We provide a mechanism of this histone cross-talk and show that H4K16ac and H2BUb play crucial roles in H3K79 di- and trimethylation in vitro and in vivo. These data reveal mechanisms that control H3K79 methylation and demonstrate how H4K16ac, H3K79me, and H2BUb function together to regulate gene transcription and gene silencing to ensure optimal maintenance and propagation of an epigenetic state.

scholarly journals Structural basis of recognition and destabilization of the histone H2B ubiquitinated nucleosome by the DOT1L histone H3 Lys79 methyltransferase

2019 ◽  
Vol 33 (11-12) ◽  
pp. 620-625 ◽  
Author(s):  
Seongmin Jang ◽  
Chanshin Kang ◽  
Han-Sol Yang ◽  
Taeyang Jung ◽  
Hans Hebert ◽  
...  
Keyword(s):  
Histone H3 ◽  
Structural Basis ◽  
Histone H2b

scholarly journals Structural basis of the regulation of normal and oncogenic methylation of nucleosomal histone H3 Lys36 by NSD2

2020 ◽  
Author(s):  
Ko Sato ◽  
Amarjeet Kumar ◽  
Keisuke Hamada ◽  
Chikako Okada ◽  
Asako Oguni ◽  
...  
Keyword(s):  
Histone H3 ◽  
Point Mutations ◽  
Polycomb Group ◽  
Structural Basis ◽  
Nucleosomal Dna ◽  
Oncogenic Mutations ◽  
Repressive Effect ◽  
Binding Cleft ◽  
Dynamics Simulations ◽  
Nucleosome Binding

SummaryDimethylated histone H3 Lys36 (H3K36me2) regulates gene expression by antagonizing the repressive effect of polycomb-group proteins. Aberrant upregulation of H3K36me2, either by overexpression or point mutations of NSD2/MMSET, an H3K36 dimethyltransferase, is found in various cancers, including multiple myeloma. To understand the mechanism underlying its regulation, here we report the cryo-electron microscopy structure of the catalytic fragment of NSD2 bound to the nucleosome at 2.8 Å resolution. The nucleosomal DNA is partially unwrapped at superhelix location +5.5, facilitating the access of NSD2 to H3K36. NSD2 interacts with DNA and H2A along with H3. The autoinhibitory loop of NSD2 changes its conformation upon nucleosome binding to accommodate H3 in its substrate-binding cleft. Kinetic analysis revealed two oncogenic mutations, E1099K and T1150A, to aberrantly activate NSD2 by increasing its catalytic turnover but not the nucleosome affinity. Molecular dynamics simulations suggested that in both mutants, the autoinhibitory loop adopts an open state that can accommodate H3 more often than the wild type. We propose that E1099K and T1150A destabilize the interactions that keep the autoinhibitory loop closed, thereby enhancing the catalytic turnover. Our analyses would guide the development of specific inhibitors of NSD2 for the treatment of various cancers.

scholarly journals Structural basis of recognition and destabilization of histone H2B ubiquitinated nucleosome by DOT1L histone H3 Lys79 methyltransferase

2018 ◽  
Author(s):  
Seongmin Jang ◽  
Chanshin Kang ◽  
Han-Sol Yang ◽  
Taeyang Jung ◽  
Hans Hebert ◽  
...  
Keyword(s):  
Single Molecule ◽  
Cross Talk ◽  
Molecular Basis ◽  
Histone H3 ◽  
Structural Basis ◽  
Histone H2b ◽  
Single Molecule Fret ◽  
Catalytic Function ◽  
Histone H3 Methylation ◽  
Hydrophobic Helix

AbstractDOT1L is a histone H3 Lys79 methyltransferase whose activity is stimulated by histone H2B Lys120 ubiquitination, suggesting cross-talk between histone H3 methylation and H2B-ubiquitination. Here, we present cryo-EM structures of DOT1L complex with unmodified and H2B-ubiquitinated nucleosomes, showing that DOT1L recognizes H2B-ubiquitin and the H2A/H2B acidic patch through a C-terminal hydrophobic helix and an arginine anchor in DOT1L respectively. Furthermore, the structures combined with single-molecule FRET experiment show that H2B-ubiquitination enhances a non-catalytic function of DOT1L destabilizing nucleosome. These results establish the molecular basis of the cross-talk between H2B ubiquitination and H3 Lys79 methylation as well as nucleosome destabilization by DOT1L.

scholarly journals Structural Basis of LSD1-CoREST Selectivity in Histone H3 Recognition

2007 ◽  
Vol 282 (28) ◽  
pp. 20070-20074 ◽  
Author(s):  
Federico Forneris ◽  
Claudia Binda ◽  
Antonio Adamo ◽  
Elena Battaglioli ◽  
Andrea Mattevi
Keyword(s):  
Histone H3 ◽  
Structural Basis

scholarly journals Sites of Acetylation on Newly Synthesized Histone H4 Are Required for Chromatin Assembly and DNA Damage Response Signaling

2013 ◽  
Vol 33 (16) ◽  
pp. 3286-3298 ◽  
Author(s):  
Zhongqi Ge ◽  
Devi Nair ◽  
Xiaoyan Guan ◽  
Neha Rastogi ◽  
Michael A. Freitas ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Damage Response ◽  
Histone H3 ◽  
Model Organism ◽  
Strand Break ◽  
Chromatin Assembly ◽  
Histone H4 ◽  
Histone H4 Acetylation ◽  
Damage Response ◽  
A Site

The best-characterized acetylation of newly synthesized histone H4 is the diacetylation of the NH2-terminal tail on lysines 5 and 12. Despite its evolutionary conservation, this pattern of modification has not been shown to be essential for either viability or chromatin assembly in any model organism. We demonstrate that mutations in histone H4 lysines 5 and 12 in yeast confer hypersensitivity to replication stress and DNA-damaging agents when combined with mutations in histone H4 lysine 91, which has also been found to be a site of acetylation on soluble histone H4. In addition, these mutations confer a dramatic decrease in cell viability when combined with mutations in histone H3 lysine 56. We also show that mutation of the sites of acetylation on newly synthesized histone H4 results in defects in the reassembly of chromatin structure that accompanies the repair of HO-mediated double-strand breaks. This defect is not due to a decrease in the level of histone H3 lysine 56 acetylation. Intriguingly, mutations that alter the sites of newly synthesized histone H4 acetylation display a marked decrease in levels of phosphorylated H2A (γ-H2AX) in chromatin surrounding the double-strand break. These results indicate that the sites of acetylation on newly synthesized histones H3 and H4 can function in nonoverlapping ways that are required for chromatin assembly, viability, and DNA damage response signaling.

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