1
|
Zhang C, Liu W, Xu L, Liu S, Che F. Abnormal H3K4 enzyme catalytic activity and neuronal morphology caused by ASH1L mutations in individuals with Tourette syndrome. Eur Child Adolesc Psychiatry 2024; 33:3913-3923. [PMID: 38634863 DOI: 10.1007/s00787-024-02437-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 04/04/2024] [Indexed: 04/19/2024]
Abstract
ASH1L potentially contributes to Tourette syndrome (TS) and other neuropsychiatric disorders, as our previous studies have shown. It regulates essential developmental genes by counteracting polycomb-mediated transcriptional repression, which restricts chromatin accessibility at target genes. ASH1L is highly expressed in the adult brain, playing a crucial role in the early stage. However, it remains unclear how ASH1L mutations carried by patients with TS participate in regulating neuronal growth processes leading to TS traits. Five TS families recruited in our study underwent comprehensive physical examinations and questionnaires to record clinical phenotypes and environmental impact factors. We validated the variants via Sanger sequencing and constructed two mutants near the catalytic domain of ASH1L. We conducted molecular modeling, in vitro assays, and primary neuron cultures to find the role of ASH1L in neuronal development and its correlation with TS. In this study, we validated five pathogenic ASH1L rare variants and observed symptoms in patients with simple tics and behavioral comorbidities. Mutations near the catalytic domain of TS patients cause mental state abnormalities and disrupt ASH1L function by destabilizing its spatial conformation, leading to decreased activity of catalytic H3K4, thereby affecting the neurite growth. We need to conduct larger-scale studies on TS patients and perform additional neurological evaluations on mature neurons. We first reported the effects of ASH1L mutations in TS patients, including phenotypic heterogeneity, protein function, and neurological growth. This information contributes to understanding the neurodevelopmental pathogenesis of TS in patients with ASH1L mutations.
Collapse
Affiliation(s)
- Cheng Zhang
- Department of Neurology, The Second Affiliated Hospital of Shandong University, Jinan, 250033, Shandong, China
- Department of Neurology, Linyi People's Hospital, 27 East Section of Jiefang Road Lanshan District, Linyi, 276000, Shandong, China
| | - Wenmiao Liu
- Medical Genetic Department, The Affiliated Hospital of Qingdao University, Qingdao, 266003, Shandong, China
| | - Lulu Xu
- Medical Genetic Department, The Affiliated Hospital of Qingdao University, Qingdao, 266003, Shandong, China
| | - Shiguo Liu
- Medical Genetic Department, The Affiliated Hospital of Qingdao University, Qingdao, 266003, Shandong, China.
| | - Fengyuan Che
- Department of Neurology, Linyi People's Hospital, 27 East Section of Jiefang Road Lanshan District, Linyi, 276000, Shandong, China
| |
Collapse
|
2
|
Jiang N, Li YB, Jin JY, Guo JY, Ding QR, Meng D, Zhi XL. Structural and functional insights into the epigenetic regulator MRG15. Acta Pharmacol Sin 2024; 45:879-889. [PMID: 38191914 PMCID: PMC11053006 DOI: 10.1038/s41401-023-01211-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 12/05/2023] [Indexed: 01/10/2024] Open
Abstract
MORF4-related gene on chromosome 15 (MRG15), a chromatin remodeller, is evolutionally conserved and ubiquitously expressed in mammalian tissues and cells. MRG15 plays vital regulatory roles in DNA damage repair, cell proliferation and division, cellular senescence and apoptosis by regulating both gene activation and gene repression via associations with specific histone acetyltransferase and histone deacetylase complexes. Recently, MRG15 has also been shown to rhythmically regulate hepatic lipid metabolism and suppress carcinoma progression. The unique N-terminal chromodomain and C-terminal MRG domain in MRG15 synergistically regulate its interaction with different cofactors, affecting its functions in various cell types. Thus, how MRG15 elaborately regulates target gene expression and performs diverse functions in different cellular contexts is worth investigating. In this review, we provide an in-depth discussion of how MRG15 controls multiple physiological and pathological processes.
Collapse
Affiliation(s)
- Nan Jiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Yong-Bo Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Jia-Yu Jin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Jie-Yu Guo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Qiu-Rong Ding
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Dan Meng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China.
| | - Xiu-Ling Zhi
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
3
|
Zhang XY, Li Y. PHD-BAH Domain in ASH1L Could Recognize H3K4 Methylation and Regulate the Malignant Behavior of Cholangiocarcinoma. Anticancer Agents Med Chem 2024; 24:1264-1274. [PMID: 39034728 DOI: 10.2174/0118715206312004240712072532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/14/2024] [Accepted: 06/27/2024] [Indexed: 07/23/2024]
Abstract
BACKGROUND Histone methyltransferase absent, small, or homeotic discs1-like (ASH1L) is composed of su(var)3-9, enhancer of zeste, trithorax (SET) domain, pleckstrin homology domain (PHD) domain, middle (MID) domain, and bromo adjacent homology (BAH) domain. The SET domain of ASH1L is known to mediate mediate H3K36 dimethylation (H3K36me2) modification. However, the specific functions of the PHD-BAH domain remain largely unexplored. This study aimed to explore the biological function of the PHD-BAH domain in ASH1L. METHODS We employed a range of techniques, including a prokaryotic fusion protein expression purification system, pull-down assay, Isothermal Titration Calorimetry (ITC), polymerase chain reaction (PCR), and sitedirected mutagenesis, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR-Cas9) gene editing, cell culture experiment, western blot, cell proliferation assay, and cell apoptosis test. RESULTS The PHD-BAH domain in ASH1L preferentially binds to the H3K4me2 peptide over H3K4 monomethylation (H3K4me1) and H3K4 trimethylation (H3K4me3) peptide. Notably, the W2603A mutation within the PHD-BAH domain could disrupt the interaction with H3K4me2 in vitro. Compared with wild-type Cholangiocarcinoma (CHOL) cells, deletion of the PHD-BAH domain in ASH1L led to increased CHOL cell apoptosis and reduced cell proliferation (P < 0.001). Additionally, the W2603A mutation affected the regulation of the proteasome 20S subunit beta (PSMB) family gene set. CONCLUSION W2603A mutation was crucial for the interaction between the PHD-BAH domain and the H3K4me2 peptide. ASH1L regulated CHOL cell survival and proliferation through its PHD-BAH domain by modulating the expression of the PSMB family gene set.
Collapse
Affiliation(s)
- Xiang-Yu Zhang
- Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
| | - Yue Li
- External Cooperation Liaison Office, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, Henan, China
| |
Collapse
|
4
|
Al-Harthi S, Li H, Winkler A, Szczepski K, Deng J, Grembecka J, Cierpicki T, Jaremko Ł. MRG15 activates histone methyltransferase activity of ASH1L by recruiting it to the nucleosomes. Structure 2023; 31:1200-1207.e5. [PMID: 37527654 DOI: 10.1016/j.str.2023.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 05/16/2023] [Accepted: 07/05/2023] [Indexed: 08/03/2023]
Abstract
ASH1L is a histone methyltransferase that regulates gene expression through methylation of histone H3 on lysine K36. While the catalytic SET domain of ASH1L has low intrinsic activity, several studies found that it can be vastly enhanced by the interaction with MRG15 protein and proposed allosteric mechanism of releasing its autoinhibited conformation. Here, we found that full-length MRG15, but not the MRG domain alone, can enhance the activity of the ASH1L SET domain. In addition, we showed that catalytic activity of MRG15-ASH1L depends on nucleosome binding mediated by MRG15 chromodomain. We found that in solution MRG15 binds to ASH1L, but has no impact on the conformation of the SET domain autoinhibitory loop or the S-adenosylmethionine cofactor binding site. Moreover, MRG15 binding did not impair the potency of small molecule inhibitors of ASH1L. These findings suggest that MRG15 functions as an adapter that enhances ASH1L catalytic activity by recruiting nucleosome substrate.
Collapse
Affiliation(s)
- Samah Al-Harthi
- Smart-Health Initiative (SHI) and Red Sea Research Center (RSRC), Bioscience Program, Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Hao Li
- Department of Pathology, University of Michigan, 1150 West Medical Center Dr, MSRB I, Room 4510D, Ann Arbor, MI 48108, USA
| | - Alyssa Winkler
- Department of Pathology, University of Michigan, 1150 West Medical Center Dr, MSRB I, Room 4510D, Ann Arbor, MI 48108, USA
| | - Kacper Szczepski
- Smart-Health Initiative (SHI) and Red Sea Research Center (RSRC), Bioscience Program, Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Jing Deng
- Department of Pathology, University of Michigan, 1150 West Medical Center Dr, MSRB I, Room 4510D, Ann Arbor, MI 48108, USA
| | - Jolanta Grembecka
- Department of Pathology, University of Michigan, 1150 West Medical Center Dr, MSRB I, Room 4510D, Ann Arbor, MI 48108, USA
| | - Tomasz Cierpicki
- Department of Pathology, University of Michigan, 1150 West Medical Center Dr, MSRB I, Room 4510D, Ann Arbor, MI 48108, USA.
| | - Łukasz Jaremko
- Smart-Health Initiative (SHI) and Red Sea Research Center (RSRC), Bioscience Program, Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
| |
Collapse
|
5
|
Maritz C, Khaleghi R, Yancoskie MN, Diethelm S, Brülisauer S, Ferreira NS, Jiang Y, Sturla SJ, Naegeli H. ASH1L-MRG15 methyltransferase deposits H3K4me3 and FACT for damage verification in nucleotide excision repair. Nat Commun 2023; 14:3892. [PMID: 37393406 PMCID: PMC10314917 DOI: 10.1038/s41467-023-39635-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 06/22/2023] [Indexed: 07/03/2023] Open
Abstract
To recognize DNA adducts, nucleotide excision repair (NER) deploys the XPC sensor, which detects damage-induced helical distortions, followed by engagement of TFIIH for lesion verification. Accessory players ensure that this factor handover takes place in chromatin where DNA is tightly wrapped around histones. Here, we describe how the histone methyltransferase ASH1L, once activated by MRG15, helps XPC and TFIIH to navigate through chromatin and induce global-genome NER hotspots. Upon UV irradiation, ASH1L adds H3K4me3 all over the genome (except in active gene promoters), thus priming chromatin for XPC relocations from native to damaged DNA. The ASH1L-MRG15 complex further recruits the histone chaperone FACT to DNA lesions. In the absence of ASH1L, MRG15 or FACT, XPC is misplaced and persists on damaged DNA without being able to deliver the lesions to TFIIH. We conclude that ASH1L-MRG15 makes damage verifiable by the NER machinery through the sequential deposition of H3K4me3 and FACT.
Collapse
Affiliation(s)
- Corina Maritz
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Reihaneh Khaleghi
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Michelle N Yancoskie
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Sarah Diethelm
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Sonja Brülisauer
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Natalia Santos Ferreira
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
| | - Yang Jiang
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Shana J Sturla
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Hanspeter Naegeli
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland.
| |
Collapse
|
6
|
Rodriguez Araya E, Merli ML, Cribb P, de Souza VC, Serra E. Deciphering Divergent Trypanosomatid Nuclear Complexes by Analyzing Interactomic Datasets with AlphaFold2 and Genetic Approaches. ACS Infect Dis 2023; 9:1267-1282. [PMID: 37167453 DOI: 10.1021/acsinfecdis.3c00148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Acetylation signaling pathways in trypanosomatids, a group of early branching organisms, are poorly understood due to highly divergent protein sequences. To overcome this challenge, we used interactomic datasets and AlphaFold2 (AF2)-multimer to predict direct interactions and validated them using yeast two and three-hybrid assays. We focused on MORF4 related gene (MRG) domain-containing proteins and their interactions, typically found in histone acetyltransferase/deacetylase complexes. The results identified a structurally conserved complex, TcTINTIN, which is orthologous to human and yeast trimer independent of NuA4 for transcription interaction (TINTIN) complexes; and another trimeric complex involving an MRG domain, only seen in trypanosomatids. The identification of a key component of TcTINTIN, TcMRGBP, would not have been possible through traditional homology-based methods. We also conducted molecular dynamics simulations, revealing a conformational change that potentially affects its affinity for TcBDF6. The study also revealed a novel way in which an MRG domain participates in simultaneous interactions with two MRG binding proteins binding two different surfaces, a phenomenon not previously reported. Overall, this study demonstrates the potential of using AF2-processed interactomic datasets to identify protein complexes in deeply branched eukaryotes, which can be challenging to study based on sequence similarity. The findings provide new insights into the acetylation signaling pathways in trypanosomatids, specifically highlighting the importance of MRG domain-containing proteins in forming complexes, which may have important implications for understanding the biology of these organisms and developing new therapeutics. On the other hand, our validation of AF2 models for the determination of multiprotein complexes illuminates the power of using such artificial intelligence-derived tools in the future development of biology.
Collapse
Affiliation(s)
- Elvio Rodriguez Araya
- Instituto de Biología Molecular y Celular de Rosario, CONICET, Suipacha 590, CP2000 Rosario, Argentina
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, CP2000 Rosario, Argentina
| | - Marcelo L Merli
- Instituto de Biología Molecular y Celular de Rosario, CONICET, Suipacha 590, CP2000 Rosario, Argentina
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, CP2000 Rosario, Argentina
| | - Pamela Cribb
- Instituto de Biología Molecular y Celular de Rosario, CONICET, Suipacha 590, CP2000 Rosario, Argentina
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, CP2000 Rosario, Argentina
| | | | - Esteban Serra
- Instituto de Biología Molecular y Celular de Rosario, CONICET, Suipacha 590, CP2000 Rosario, Argentina
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, CP2000 Rosario, Argentina
| |
Collapse
|
7
|
Devoucoux M, Roques C, Lachance C, Lashgari A, Joly-Beauparlant C, Jacquet K, Alerasool N, Prudente A, Taipale M, Droit A, Lambert JP, Hussein SMI, Côté J. MRG Proteins Are Shared by Multiple Protein Complexes With Distinct Functions. Mol Cell Proteomics 2022; 21:100253. [PMID: 35636729 PMCID: PMC9253478 DOI: 10.1016/j.mcpro.2022.100253] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 11/17/2022] Open
Abstract
MRG15/MORF4L1 is a highly conserved protein in eukaryotes that contains a chromodomain (CHD) recognizing methylation of lysine 36 on histone H3 (H3K36me3) in chromatin. Intriguingly, it has been reported in the literature to interact with several different factors involved in chromatin modifications, gene regulation, alternative mRNA splicing, and DNA repair by homologous recombination. To get a complete and reliable picture of associations in physiological conditions, we used genome editing and tandem affinity purification to analyze the stable native interactome of human MRG15, its paralog MRGX/MORF4L2 that lacks the CHD, and MRGBP (MRG-binding protein) in isogenic K562 cells. We found stable interchangeable association of MRG15 and MRGX with the NuA4/TIP60 histone acetyltransferase/chromatin remodeler, Sin3B histone deacetylase/demethylase, ASH1L histone methyltransferase, and PALB2-BRCA2 DNA repair protein complexes. These associations were further confirmed and analyzed by CRISPR tagging of endogenous proteins and comparison of expressed isoforms. Importantly, based on structural information, point mutations could be introduced that specifically disrupt MRG15 association with some complexes but not others. Most interestingly, we also identified a new abundant native complex formed by MRG15/X-MRGBP-BRD8-EP400NL (EP400 N-terminal like) that is functionally similar to the yeast TINTIN (Trimer Independent of NuA4 for Transcription Interactions with Nucleosomes) complex. Our results show that EP400NL, being homologous to the N-terminal region of NuA4/TIP60 subunit EP400, creates TINTIN by competing for BRD8 association. Functional genomics indicate that human TINTIN plays a role in transcription of specific genes. This is most likely linked to the H4ac-binding bromodomain of BRD8 along the H3K36me3-binding CHD of MRG15 on the coding region of transcribed genes. Taken together, our data provide a complete detailed picture of human MRG proteins-associated protein complexes, which are essential to understand and correlate their diverse biological functions in chromatin-based nuclear processes.
Collapse
Affiliation(s)
- Maëva Devoucoux
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada
| | - Céline Roques
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada
| | - Catherine Lachance
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada
| | - Anahita Lashgari
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada; Department of Molecular Medicine, Laval University Cancer Research Center, CHU de Québec-Université Laval Research Center, Big Data Research Center, Université Laval, Quebec City, Quebec, Canada
| | - Charles Joly-Beauparlant
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Pavillon CHUL, Quebec City, Quebec, Canada; Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Karine Jacquet
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada
| | - Nader Alerasool
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Alexandre Prudente
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada
| | - Mikko Taipale
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Arnaud Droit
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Pavillon CHUL, Quebec City, Quebec, Canada; Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Jean-Philippe Lambert
- Department of Molecular Medicine, Laval University Cancer Research Center, CHU de Québec-Université Laval Research Center, Big Data Research Center, Université Laval, Quebec City, Quebec, Canada
| | - Samer M I Hussein
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada
| | - Jacques Côté
- St. Patrick Research Group in Basic Oncology, Laval University Cancer Research Center, Oncology Division of CHU de Québec-Université Laval Research Center, Quebec City, Quebec, Canada.
| |
Collapse
|
8
|
Lam UTF, Tan BKY, Poh JJX, Chen ES. Structural and functional specificity of H3K36 methylation. Epigenetics Chromatin 2022; 15:17. [PMID: 35581654 PMCID: PMC9116022 DOI: 10.1186/s13072-022-00446-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/04/2022] [Indexed: 12/20/2022] Open
Abstract
The methylation of histone H3 at lysine 36 (H3K36me) is essential for maintaining genomic stability. Indeed, this methylation mark is essential for proper transcription, recombination, and DNA damage response. Loss- and gain-of-function mutations in H3K36 methyltransferases are closely linked to human developmental disorders and various cancers. Structural analyses suggest that nucleosomal components such as the linker DNA and a hydrophobic patch constituted by histone H2A and H3 are likely determinants of H3K36 methylation in addition to the histone H3 tail, which encompasses H3K36 and the catalytic SET domain. Interaction of H3K36 methyltransferases with the nucleosome collaborates with regulation of their auto-inhibitory changes fine-tunes the precision of H3K36me in mediating dimethylation by NSD2 and NSD3 as well as trimethylation by Set2/SETD2. The identification of specific structural features and various cis-acting factors that bind to different forms of H3K36me, particularly the di-(H3K36me2) and tri-(H3K36me3) methylated forms of H3K36, have highlighted the intricacy of H3K36me functional significance. Here, we consolidate these findings and offer structural insight to the regulation of H3K36me2 to H3K36me3 conversion. We also discuss the mechanisms that underlie the cooperation between H3K36me and other chromatin modifications (in particular, H3K27me3, H3 acetylation, DNA methylation and N6-methyladenosine in RNAs) in the physiological regulation of the epigenomic functions of chromatin.
Collapse
Affiliation(s)
- Ulysses Tsz Fung Lam
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Bryan Kok Yan Tan
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - John Jia Xin Poh
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ee Sin Chen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- National University Health System (NUHS), Singapore, Singapore.
- NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Integrative Sciences & Engineering Programme, National University of Singapore, Singapore, Singapore.
| |
Collapse
|
9
|
Cheon S, Culver AM, Bagnell AM, Ritchie FD, Vacharasin JM, McCord MM, Papendorp CM, Chukwurah E, Smith AJ, Cowen MH, Moreland TA, Ghate PS, Davis SW, Liu JS, Lizarraga SB. Counteracting epigenetic mechanisms regulate the structural development of neuronal circuitry in human neurons. Mol Psychiatry 2022; 27:2291-2303. [PMID: 35210569 PMCID: PMC9133078 DOI: 10.1038/s41380-022-01474-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 02/02/2022] [Indexed: 01/23/2023]
Abstract
Autism spectrum disorders (ASD) are associated with defects in neuronal connectivity and are highly heritable. Genetic findings suggest that there is an overrepresentation of chromatin regulatory genes among the genes associated with ASD. ASH1 like histone lysine methyltransferase (ASH1L) was identified as a major risk factor for ASD. ASH1L methylates Histone H3 on Lysine 36, which is proposed to result primarily in transcriptional activation. However, how mutations in ASH1L lead to deficits in neuronal connectivity associated with ASD pathogenesis is not known. We report that ASH1L regulates neuronal morphogenesis by counteracting the catalytic activity of Polycomb Repressive complex 2 group (PRC2) in stem cell-derived human neurons. Depletion of ASH1L decreases neurite outgrowth and decreases expression of the gene encoding the neurotrophin receptor TrkB whose signaling pathway is linked to neuronal morphogenesis. The neuronal morphogenesis defect is overcome by inhibition of PRC2 activity, indicating that a balance between the Trithorax group protein ASH1L and PRC2 activity determines neuronal morphology. Thus, our work suggests that ASH1L may epigenetically regulate neuronal morphogenesis by modulating pathways like the BDNF-TrkB signaling pathway. Defects in neuronal morphogenesis could potentially impair the establishment of neuronal connections which could contribute to the neurodevelopmental pathogenesis associated with ASD in patients with ASH1L mutations.
Collapse
Affiliation(s)
- Seonhye Cheon
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Allison M Culver
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Anna M Bagnell
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Foster D Ritchie
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Janay M Vacharasin
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Mikayla M McCord
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Carin M Papendorp
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
| | - Evelyn Chukwurah
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Austin J Smith
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Mara H Cowen
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Trevor A Moreland
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Pankaj S Ghate
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Shannon W Davis
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA
| | - Judy S Liu
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
- Center for Translational Neuroscience, Robert J. and Nancy D. Carney Institute for Brain Science and Brown Institute for Translational Science, Brown University, Providence, RI, USA
- Department of Neurology, Rhode Island Hospital and Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Sofia B Lizarraga
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA.
- Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, USA.
| |
Collapse
|
10
|
Taylor-Papadimitriou J, Burchell JM. Histone Methylases and Demethylases Regulating Antagonistic Methyl Marks: Changes Occurring in Cancer. Cells 2022; 11:1113. [PMID: 35406676 PMCID: PMC8997813 DOI: 10.3390/cells11071113] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/17/2022] [Accepted: 03/22/2022] [Indexed: 02/06/2023] Open
Abstract
Epigenetic regulation of gene expression is crucial to the determination of cell fate in development and differentiation, and the Polycomb (PcG) and Trithorax (TrxG) groups of proteins, acting antagonistically as complexes, play a major role in this regulation. Although originally identified in Drosophila, these complexes are conserved in evolution and the components are well defined in mammals. Each complex contains a protein with methylase activity (KMT), which can add methyl groups to a specific lysine in histone tails, histone 3 lysine 27 (H3K27), by PcG complexes, and H3K4 and H3K36 by TrxG complexes, creating transcriptionally repressive or active marks, respectively. Histone demethylases (KDMs), identified later, added a new dimension to histone methylation, and mutations or changes in levels of expression are seen in both methylases and demethylases and in components of the PcG and TrX complexes across a range of cancers. In this review, we focus on both methylases and demethylases governing the methylation state of the suppressive and active marks and consider their action and interaction in normal tissues and in cancer. A picture is emerging which indicates that the changes which occur in cancer during methylation of histone lysines can lead to repression of genes, including tumour suppressor genes, or to the activation of oncogenes. Methylases or demethylases, which are themselves tumour suppressors, are highly mutated. Novel targets for cancer therapy have been identified and a methylase (KMT6A/EZH2), which produces the repressive H3K27me3 mark, and a demethylase (KDM1A/LSD1), which demethylates the active H3K4me2 mark, are now under clinical evaluation.
Collapse
|
11
|
Sato K, Kumar A, Hamada K, Okada C, Oguni A, Machiyama A, Sakuraba S, Nishizawa T, Nureki O, Kono H, Ogata K, Sengoku T. Structural basis of the regulation of the normal and oncogenic methylation of nucleosomal histone H3 Lys36 by NSD2. Nat Commun 2021; 12:6605. [PMID: 34782608 PMCID: PMC8593083 DOI: 10.1038/s41467-021-26913-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 10/28/2021] [Indexed: 12/24/2022] Open
Abstract
Dimethylated histone H3 Lys36 (H3K36me2) regulates gene expression, and aberrant H3K36me2 upregulation, resulting from either the overexpression or point mutation of the dimethyltransferase NSD2, is found in various cancers. Here we report the cryo-electron microscopy structure of NSD2 bound to the nucleosome. Nucleosomal DNA is partially unwrapped, facilitating NSD2 access to H3K36. NSD2 interacts with DNA and H2A along with H3. The NSD2 autoinhibitory loop changes its conformation upon nucleosome binding to accommodate H3 in its substrate-binding cleft. Kinetic analysis revealed that two oncogenic mutations, E1099K and T1150A, increase NSD2 catalytic turnover. 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 catalytic turnover. Our analyses guide the development of specific inhibitors of NSD2.
Collapse
Affiliation(s)
- Ko Sato
- grid.268441.d0000 0001 1033 6139Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 Japan
| | - Amarjeet Kumar
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, 8-1-7 Umemidai, Kizugawa, Kyoto 619-0215 Japan
| | - Keisuke Hamada
- grid.268441.d0000 0001 1033 6139Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 Japan
| | - Chikako Okada
- grid.268441.d0000 0001 1033 6139Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 Japan
| | - Asako Oguni
- grid.268441.d0000 0001 1033 6139Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 Japan
| | - Ayumi Machiyama
- grid.268441.d0000 0001 1033 6139Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004 Japan
| | - Shun Sakuraba
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, 8-1-7 Umemidai, Kizugawa, Kyoto 619-0215 Japan
| | - Tomohiro Nishizawa
- grid.26999.3d0000 0001 2151 536XDepartment of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan ,grid.268441.d0000 0001 1033 6139Present Address: Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Osamu Nureki
- grid.26999.3d0000 0001 2151 536XDepartment of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 Japan
| | - Hidetoshi Kono
- Institute for Quantum Life Science, National Institutes for Quantum Science and Technology, 8-1-7 Umemidai, Kizugawa, Kyoto 619-0215 Japan
| | - Kazuhiro Ogata
- Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan.
| | - Toru Sengoku
- Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa, 236-0004, Japan.
| |
Collapse
|
12
|
Shrestha A, Kim N, Lee SJ, Jeon YH, Song JJ, An H, Cho SJ, Kadayat TM, Chin J. Targeting the Nuclear Receptor-Binding SET Domain Family of Histone Lysine Methyltransferases for Cancer Therapy: Recent Progress and Perspectives. J Med Chem 2021; 64:14913-14929. [PMID: 34488340 DOI: 10.1021/acs.jmedchem.1c01116] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nuclear receptor-binding SET domain (NSD) proteins are a class of histone lysine methyltransferases (HKMTases) that are amplified, mutated, translocated, or overexpressed in various types of cancers. Several campaigns to develop NSD inhibitors for cancer treatment have begun following recent advances in knowledge of NSD1, NSD2, and NSD3 structures and functions as well as the U.S. FDA approval of the first HKMTase inhibitor (tazemetostat, an EZH2 inhibitor) to treat follicular lymphoma and epithelioid sarcoma. This perspective highlights recent findings on the structures of catalytic su(var), enhancer-of-zeste, trithorax (SET) domains and other functional domains of NSD methyltransferases. In addition, recent progress and efforts to discover NSD-specific small molecule inhibitors against cancer-targeting catalytic SET domains, plant homeodomains, and proline-tryptophan-tryptophan-proline domains are summarized.
Collapse
Affiliation(s)
- Aarajana Shrestha
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Nayeon Kim
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Su-Jeong Lee
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Yong Hyun Jeon
- Laboratory Animal Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Ji-Joon Song
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Hongchan An
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Sung Jin Cho
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Tara Man Kadayat
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| | - Jungwook Chin
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Republic of Korea
| |
Collapse
|
13
|
Lindehell H, Glotov A, Dorafshan E, Schwartz YB, Larsson J. The role of H3K36 methylation and associated methyltransferases in chromosome-specific gene regulation. SCIENCE ADVANCES 2021; 7:eabh4390. [PMID: 34597135 PMCID: PMC10938550 DOI: 10.1126/sciadv.abh4390] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
In Drosophila, two chromosomes require special mechanisms to balance their transcriptional output to the rest of the genome. These are the male-specific lethal complex targeting the male X chromosome and Painting of fourth targeting chromosome 4. Here, we explore the role of histone H3 methylated at lysine-36 (H3K36) and the associated methyltransferases—Set2, NSD, and Ash1—in these two chromosome-specific systems. We show that the loss of Set2 impairs the MSL complex–mediated dosage compensation; however, the effect is not recapitulated by H3K36 replacement and indicates an alternative target of Set2. Unexpectedly, balanced transcriptional output from the fourth chromosome requires intact H3K36 and depends on the additive functions of NSD and Ash1. We conclude that H3K36 methylation and the associated methyltransferases are important factors to balance transcriptional output of the male X chromosome and the fourth chromosome. Furthermore, our study highlights the pleiotropic effects of these enzymes.
Collapse
Affiliation(s)
- Henrik Lindehell
- Department of Molecular Biology, Umeå University, SE-90187 Umeå, Sweden
| | - Alexander Glotov
- Department of Molecular Biology, Umeå University, SE-90187 Umeå, Sweden
| | - Eshagh Dorafshan
- Department of Molecular Biology, Umeå University, SE-90187 Umeå, Sweden
| | | | | |
Collapse
|
14
|
Davidovich C, Zhang Q. Allosteric regulation of histone lysine methyltransferases: from context-specific regulation to selective drugs. Biochem Soc Trans 2021; 49:591-607. [PMID: 33769454 PMCID: PMC8106495 DOI: 10.1042/bst20200238] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 02/06/2023]
Abstract
Histone lysine methyltransferases (HKMTs) are key regulators of many cellular processes. By definition, HKMTs catalyse the methylation of lysine residues in histone proteins. The enzymatic activities of HKMTs are under precise control, with their allosteric regulation emerging as a prevalent paradigm. We review the molecular mechanisms of allosteric regulation of HKMTs using well-studied histone H3 (K4, K9, K27 and K36) methyltransferases as examples. We discuss the current advances and future potential in targeting allosteric sites of HKMTs for drug development.
Collapse
Affiliation(s)
- Chen Davidovich
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia
- EMBL-Australia and the ARC Centre of Excellence in Advanced Molecular Imaging, Clayton, Victoria, Australia
| | - Qi Zhang
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia
| |
Collapse
|
15
|
Gsell C, Richly H, Coin F, Naegeli H. A chromatin scaffold for DNA damage recognition: how histone methyltransferases prime nucleosomes for repair of ultraviolet light-induced lesions. Nucleic Acids Res 2020; 48:1652-1668. [PMID: 31930303 PMCID: PMC7038933 DOI: 10.1093/nar/gkz1229] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/18/2019] [Accepted: 12/23/2019] [Indexed: 02/07/2023] Open
Abstract
The excision of mutagenic DNA adducts by the nucleotide excision repair (NER) pathway is essential for genome stability, which is key to avoiding genetic diseases, premature aging, cancer and neurologic disorders. Due to the need to process an extraordinarily high damage density embedded in the nucleosome landscape of chromatin, NER activity provides a unique functional caliper to understand how histone modifiers modulate DNA damage responses. At least three distinct lysine methyltransferases (KMTs) targeting histones have been shown to facilitate the detection of ultraviolet (UV) light-induced DNA lesions in the difficult to access DNA wrapped around histones in nucleosomes. By methylating core histones, these KMTs generate docking sites for DNA damage recognition factors before the chromatin structure is ultimately relaxed and the offending lesions are effectively excised. In view of their function in priming nucleosomes for DNA repair, mutations of genes coding for these KMTs are expected to cause the accumulation of DNA damage promoting cancer and other chronic diseases. Research on the question of how KMTs modulate DNA repair might pave the way to the development of pharmacologic agents for novel therapeutic strategies.
Collapse
Affiliation(s)
- Corina Gsell
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Winterthurerstrasse 260, 8057 Zurich, Switzerland
| | - Holger Richly
- Boehringer Ingelheim Pharma, Department of Molecular Biology, Birkendorfer Str. 65, 88397 Biberach an der Riß, Germany
| | - Frédéric Coin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Equipe Labélisée Ligue contre le Cancer, Illkirch Cedex, Strasbourg, France
| | - Hanspeter Naegeli
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Winterthurerstrasse 260, 8057 Zurich, Switzerland
| |
Collapse
|
16
|
Abstract
Trithorax histone methyltransferase Ash1/ASH1L is tightly regulated because it activates developmental gene transcription and counteracts Polycomb silencing. In this issue of Structure, Lee et al. (2019) and Hou et al. (2019) report the crystal structure of ASH1L bound to its activator MRG15 and suggest a mechanism that releases ASH1L auto-inhibition.
Collapse
|
17
|
Genetic Dissection Reveals the Role of Ash1 Domains in Counteracting Polycomb Repression. G3-GENES GENOMES GENETICS 2019; 9:3801-3812. [PMID: 31540973 PMCID: PMC6829142 DOI: 10.1534/g3.119.400579] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Antagonistic functions of Polycomb and Trithorax proteins are essential for proper development of all metazoans. While the Polycomb proteins maintain the repressed state of many key developmental genes, the Trithorax proteins ensure that these genes stay active in cells where they have to be expressed. Ash1 is the Trithorax protein that was proposed to counteract Polycomb repression by methylating lysine 36 of histone H3. However, it was recently shown that genetic replacement of Drosophila histone H3 with the variant that carried Arginine instead of Lysine at position 36 did not impair the ability of Ash1 to counteract Polycomb repression. This argues that Ash1 counteracts Polycomb repression by methylating yet unknown substrate(s) and that it is time to look beyond Ash1 methyltransferase SET domain, at other evolutionary conserved parts of the protein that received little attention. Here we used Drosophila genetics to demonstrate that Ash1 requires each of the BAH, PHD and SET domains to counteract Polycomb repression, while AT hooks are dispensable. Our findings argue that, in vivo, Ash1 acts as a multimer. Thereby it can combine the input of the SET domain and PHD-BAH cassette residing in different peptides. Finally, using new loss of function alleles, we show that zygotic Ash1 is required to prevent erroneous repression of homeotic genes of the bithorax complex in the embryo.
Collapse
|
18
|
Bilokapic S, Halic M. Nucleosome and ubiquitin position Set2 to methylate H3K36. Nat Commun 2019; 10:3795. [PMID: 31439846 PMCID: PMC6706414 DOI: 10.1038/s41467-019-11726-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 08/01/2019] [Indexed: 12/19/2022] Open
Abstract
Histone H3 lysine 36 methylation (H3K36me) is a conserved histone modification deposited by the Set2 methyltransferases. Recent findings show that over-expression or mutation of Set2 enzymes promotes cancer progression, however, mechanisms of H3K36me are poorly understood. Set2 enzymes show spurious activity on histones and histone tails, and it is unknown how they obtain specificity to methylate H3K36 on the nucleosome. In this study, we present 3.8 Å cryo-EM structure of Set2 bound to the mimic of H2B ubiquitinated nucleosome. Our structure shows that Set2 makes extensive interactions with the H3 αN, the H3 tail, the H2A C-terminal tail and stabilizes DNA in the unwrapped conformation, which positions Set2 to specifically methylate H3K36. Moreover, we show that ubiquitin contributes to Set2 positioning on the nucleosome and stimulates the methyltransferase activity. Notably, our structure uncovers interfaces that can be targeted by small molecules for development of future cancer therapies.
Collapse
Affiliation(s)
- Silvija Bilokapic
- Department of Structural Biology, St. Jude Children's Research Hospital, 263 Danny Thomas Place, Memphis, TN, 38105, USA.
| | - Mario Halic
- Department of Structural Biology, St. Jude Children's Research Hospital, 263 Danny Thomas Place, Memphis, TN, 38105, USA.
| |
Collapse
|