Regulation of histone methylation by automethylation of PRC2

Mapping Intimacies ◽

10.1101/343020 ◽

2018 ◽

Cited By ~ 5

Author(s):

Xueyin Wang ◽

Yicheng Long ◽

Richard D. Paucek ◽

Anne R. Gooding ◽

Thomas Lee ◽

...

Keyword(s):

Transcriptional Repression ◽

Histone Methyltransferase ◽

Post Translational Modification ◽

Methyltransferase Activity ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Flexible Loop ◽

Lysine Residues ◽

In Cis ◽

Pseudosubstrate Sequence

ABSTRACTPolycomb Repressive Complex 2 (PRC2) is a histone methyltransferase whose function is critical for regulating transcriptional repression in many eukaryotes including humans. Its catalytic moiety EZH2 is responsible for the tri-methylation of H3K27 and also undergoes automethylation. Using mass spectroscopic analysis of recombinant human PRC2, we identified three methylated lysine residues (K510, K514, K515) on a disordered but highly conserved loop of EZH2. These lysines were mostly mono- and di-methylated. Either mutation of these lysines or their methylation increases PRC2 histone methyltransferase activity. In addition, mutation of these three lysines in HEK293T cells using CRISPR genome-editing increases global H3K27 methylation levels. EZH2 automethylation occurs intramolecularly (in cis) by methylation of a pseudosubstrate sequence on the flexible loop. This post-translational modification andcis-regulation of PRC2 are analogous to the activation of many protein kinases by autophosphorylation. We therefore propose that EZH2 automethylation provides a way for PRC2 to modulate its histone methyltransferase activity by sensing histone H3 tails, SAM concentration, and perhaps other effectors.

Download Full-text

Identification of a PRC2 Accessory Subunit Required for Subtelomeric H3K27 Methylation in Neurospora crassa

Molecular and Cellular Biology ◽

10.1128/mcb.00003-20 ◽

2020 ◽

Vol 40 (11) ◽

Author(s):

Kevin J. McNaught ◽

Elizabeth T. Wiles ◽

Eric U. Selker

Keyword(s):

Neurospora Crassa ◽

Transcriptional Repression ◽

Sequence Similarity ◽

Model Organism ◽

Content Type ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Accessory Subunit ◽

Genomic Regions ◽

Similarity Searches

ABSTRACT Polycomb repressive complex 2 (PRC2) catalyzes methylation of histone H3 at lysine 27 (H3K27) in genomic regions of most eukaryotes and is critical for maintenance of the associated transcriptional repression. However, the mechanisms that shape the distribution of H3K27 methylation, such as recruitment of PRC2 to chromatin and/or stimulation of PRC2 activity, are unclear. Here, using a forward genetic approach in the model organism Neurospora crassa, we identified two alleles of a gene, NCU04278, encoding an unknown PRC2 accessory subunit (PAS). Loss of PAS resulted in losses of H3K27 methylation concentrated near the chromosome ends and derepression of a subset of associated subtelomeric genes. Immunoprecipitation followed by mass spectrometry confirmed reciprocal interactions between PAS and known PRC2 subunits, and sequence similarity searches demonstrated that PAS is not unique to N. crassa. PAS homologs likely influence the distribution of H3K27 methylation and underlying gene repression in a variety of fungal lineages.

Download Full-text

Estrogen receptor acetylation and phosphorylation in hormone responses

Breast Cancer Online ◽

10.1017/s1470903105003196 ◽

2005 ◽

Vol 8 (9) ◽

Author(s):

C. Wang ◽

M. Fu ◽

R. G. Pestell

Keyword(s):

Estrogen Receptor ◽

Dna Sequences ◽

Transcriptional Repression ◽

Estrogen Receptor Alpha ◽

Estrogen Therapy ◽

Estrogen Signaling ◽

Hormone Signaling ◽

Post Translational Modification ◽

Lysine Residues ◽

Hormone Responses

Histone acetylation is thought to facilitate binding of transcription factors (TFs) to specific target DNA sequences by destabilizing nucleosomes bound to the promoter region of a target gene. In addition, non-histone proteins including a subset of TFs and co-activators are acetylated by p300/CBP and P/CAF. The regulation of estrogen signaling by direct estrogen receptor alpha (ERα) post-translational modification reveals a novel role for histone acetyltransferase in hormone signaling. ERα is acetylated and phosphorylated and phosphorylation occurs at multiple sites in response to kinase signaling. The finding that mutations with the ERα hinge domain lysine residues enhance hormone sensitivity suggests these residues may be involved in ligand-dependent transcriptional repression or transcriptional attenuation. Phosphorylation and acetylation of the ER regulates hormone signaling and is being assessed for a role in resistance to anti-estrogen therapy of ERα-positive patients.

Download Full-text

The histone methyltransferase activity of WHISTLE is important for the induction of apoptosis and HDAC1-mediated transcriptional repression

Experimental Cell Research ◽

10.1016/j.yexcr.2006.12.007 ◽

2007 ◽

Vol 313 (5) ◽

pp. 975-983 ◽

Cited By ~ 10

Author(s):

Sung-Mi Kim ◽

Hae-Jin Kee ◽

Nakwon Choe ◽

Ji-Young Kim ◽

Hoon Kook ◽

...

Keyword(s):

Transcriptional Repression ◽

Histone Methyltransferase ◽

Methyltransferase Activity ◽

Induction Of Apoptosis

Download Full-text

Identification of a PRC2 accessory subunit required for subtelomeric H3K27 methylation in Neurospora

10.1101/2020.01.06.896845 ◽

2020 ◽

Author(s):

Kevin J. McNaught ◽

Elizabeth T. Wiles ◽

Eric U. Selker

Keyword(s):

Transcriptional Repression ◽

Sequence Similarity ◽

Model Organism ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

Reciprocal Interactions ◽

Accessory Subunit ◽

Genomic Regions ◽

Similarity Searches ◽

Stimulation Of

ABSTRACTPolycomb repressive complex 2 (PRC2) catalyzes methylation of histone H3 lysine 27 (H3K27) in genomic regions of most eukaryotes and is critical for maintenance of the associated transcriptional repression. However, the mechanisms that shape the distribution of H3K27 methylation, such as recruitment of PRC2 to chromatin and/or stimulation of PRC2 activity, are unclear. Here, using a forward genetic approach in the model organism Neurospora crassa, we identified two alleles of a gene, NCU04278, encoding an unknown PRC2 accessory subunit (PAS). Loss of PAS resulted in losses of H3K27 methylation concentrated near the chromosome ends and derepression of a subset of associated subtelomeric genes. Immunoprecipitation followed by mass spectrometry confirmed reciprocal interactions between PAS and known PRC2 subunits, and sequence similarity searches demonstrated that PAS is not unique to N. crassa. PAS homologs likely influence the distribution of H3K27 methylation, and underlying gene repression, in a variety of fungal lineages.

Download Full-text

H3 K27M and EZHIP impede H3K27-methylation spreading by inhibiting allosterically stimulated PRC2

10.1101/2020.08.05.236737 ◽

2020 ◽

Author(s):

Siddhant U. Jain ◽

Andrew Q. Rashoff ◽

Samuel D. Krabbenhoft ◽

Dominik Hoelper ◽

Truman J. Do ◽

...

Keyword(s):

Cpg Islands ◽

Methyltransferase Activity ◽

Polycomb Repressive Complex 2 ◽

H3k27 Methylation ◽

K27m Mutation ◽

Mechanistic Insight ◽

Competitive Inhibitors ◽

Lysine Methyltransferase

AbstractDiffuse midline gliomas and posterior fossa type-A ependymomas contain the highly recurrent histone H3 K27M mutation and the H3 K27M-mimic EZHIP, respectively. In vitro, H3 K27M and EZHIP are competitive inhibitors of Polycomb Repressive Complex 2 (PRC2) lysine methyltransferase activity. In vivo, these proteins reduce overall H3K27me3 levels, however residual peaks of H3K27me3 remain at CpG islands through an unknown mechanism. Here, we report that EZHIP and H3 K27M preferentially interact with an allosterically activated form of PRC2 in vivo. The formation of H3 K27M- and EZHIP-PRC2 complexes occurs at CpG islands containing H3K27me3 and impedes PRC2 and H3K27me3 spreading. While EZHIP is not found outside of placental mammals, we find that expression of human EZHIP reduces H3K27me3 in Drosophila melanogaster through a conserved molecular mechanism. Our results highlight the mechanistic similarities between EZHIP and H3 K27M in vivo and provide mechanistic insight for the retention of residual H3K27me3 in tumors driven by these oncogenes.

Download Full-text

Review of Progress in Predicting Protein Methylation Sites

Current Organic Chemistry ◽

10.2174/1385272823666190723141347 ◽

2019 ◽

Vol 23 (15) ◽

pp. 1663-1670 ◽

Cited By ~ 1

Author(s):

Chunyan Ao ◽

Shunshan Jin ◽

Yuan Lin ◽

Quan Zou

Keyword(s):

Gene Expression ◽

Signal Transduction ◽

Transcriptional Activity ◽

Regulation Of Gene Expression ◽

Protein Methylation ◽

Biological Processes ◽

Post Translational Modification ◽

Regulatory Enzymes ◽

Lysine Residues ◽

Arginine Residues

Protein methylation is an important and reversible post-translational modification that regulates many biological processes in cells. It occurs mainly on lysine and arginine residues and involves many important biological processes, including transcriptional activity, signal transduction, and the regulation of gene expression. Protein methylation and its regulatory enzymes are related to a variety of human diseases, so improved identification of methylation sites is useful for designing drugs for a variety of related diseases. In this review, we systematically summarize and analyze the tools used for the prediction of protein methylation sites on arginine and lysine residues over the last decade.

Download Full-text

Structural basis for the regulation of nucleosome recognition and HDAC activity by histone deacetylase assemblies

Science Advances ◽

10.1126/sciadv.abd4413 ◽

2021 ◽

Vol 7 (2) ◽

pp. eabd4413

Author(s):

Jung-Hoon Lee ◽

Daniel Bollschweiler ◽

Tillman Schäfer ◽

Robert Huber

Keyword(s):

Transcriptional Repression ◽

Histone Deacetylases ◽

Active Sites ◽

Chromatin Modification ◽

Structural Basis ◽

Amino Terminal ◽

Cryo Electron Microscopy ◽

Multiple Contacts ◽

Lysine Residues ◽

Nucleosome Binding

The chromatin-modifying histone deacetylases (HDACs) remove acetyl groups from acetyl-lysine residues in histone amino-terminal tails, thereby mediating transcriptional repression. Structural makeup and mechanisms by which multisubunit HDAC complexes recognize nucleosomes remain elusive. Our cryo–electron microscopy structures of the yeast class II HDAC ensembles show that the HDAC protomer comprises a triangle-shaped assembly of stoichiometry Hda12-Hda2-Hda3, in which the active sites of the Hda1 dimer are freely accessible. We also observe a tetramer of protomers, where the nucleosome binding modules are inaccessible. Structural analysis of the nucleosome-bound complexes indicates how positioning of Hda1 adjacent to histone H2B affords HDAC catalysis. Moreover, it reveals how an intricate network of multiple contacts between a dimer of protomers and the nucleosome creates a platform for expansion of the HDAC activities. Our study provides comprehensive insight into the structural plasticity of the HDAC complex and its functional mechanism of chromatin modification.

Download Full-text

Dispersed Mutations in Histone H3 That Affect Transcriptional Repression and Chromatin Structure of the CHA1 Promoter in Saccharomyces cerevisiae

Eukaryotic Cell ◽

10.1128/ec.00233-08 ◽

2008 ◽

Vol 7 (10) ◽

pp. 1649-1660 ◽

Cited By ~ 7

Author(s):

Qiye He ◽

Cailin Yu ◽

Randall H. Morse

Keyword(s):

Saccharomyces Cerevisiae ◽

Chromatin Structure ◽

Transcriptional Repression ◽

Histone H3 ◽

Temperature Sensitive ◽

Active Chromatin ◽

Temperature Sensitive Mutants ◽

Nucleosome Structure ◽

Lysine Residues ◽

Chromatin Configuration

ABSTRACT The histone H3 amino terminus, but not that of H4, is required to prevent the constitutively bound activator Cha4 from remodeling chromatin and activating transcription at the CHA1 gene in Saccharomyces cerevisiae. Here we show that neither the modifiable lysine residues nor any specific region of the H3 tail is required for repression of CHA1. We then screened for histone H3 mutations that cause derepression of the uninduced CHA1 promoter and identified six mutants, three of which are also temperature-sensitive mutants and four of which exhibit a sin − phenotype. Histone mutant levels were similar to that of wild-type H3, and the mutations did not cause gross alterations in nucleosome structure. One specific and strongly derepressing mutation, H3 A111G, was examined in depth and found to cause a constitutively active chromatin configuration at the uninduced CHA1 promoter as well as at the ADH2 promoter. Transcriptional derepression and altered chromatin structure of the CHA1 promoter depend on the activator Cha4. These results indicate that modest perturbations in distinct regions of the nucleosome can substantially affect the repressive function of chromatin, allowing activation in the absence of a normal inducing signal (at CHA1) or of Swi/Snf (resulting in a sin − phenotype).

Download Full-text

Biocatalysis by Transglutaminases: A Review of Biotechnological Applications

Micromachines ◽

10.3390/mi9110562 ◽

2018 ◽

Vol 9 (11) ◽

pp. 562 ◽

Cited By ~ 9

Author(s):

Maria Savoca ◽

Elisa Tonoli ◽

Adeola Atobatele ◽

Elisabetta Verderio

Keyword(s):

Nutritive Value ◽

Large Family ◽

Catalytic Triad ◽

Matrix Proteins ◽

Primary Amines ◽

Biotechnological Applications ◽

Post Translational Modification ◽

The Past ◽

Lysine Residues ◽

Isopeptide Bonds

The biocatalytic activity of transglutaminases (TGs) leads to the synthesis of new covalent isopeptide bonds (crosslinks) between peptide-bound glutamine and lysine residues, but also the transamidation of primary amines to glutamine residues, which ultimately can result into protein polymerisation. Operating with a cysteine/histidine/aspartic acid (Cys/His/Asp) catalytic triad, TGs induce the post-translational modification of proteins at both physiological and pathological conditions (e.g., accumulation of matrices in tissue fibrosis). Because of the disparate biotechnological applications, this large family of protein-remodelling enzymes have stimulated an escalation of interest. In the past 50 years, both mammalian and microbial TGs polymerising activity has been exploited in the food industry for the improvement of aliments’ quality, texture, and nutritive value, other than to enhance the food appearance and increased marketability. At the same time, the ability of TGs to crosslink extracellular matrix proteins, like collagen, as well as synthetic biopolymers, has led to multiple applications in biomedicine, such as the production of biocompatible scaffolds and hydrogels for tissue engineering and drug delivery, or DNA-protein bio-conjugation and antibody functionalisation. Here, we summarise the most recent advances in the field, focusing on the utilisation of TGs-mediated protein multimerisation in biotechnological and bioengineering applications.

Download Full-text