1
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Malone HA, Roberts CWM. Chromatin remodellers as therapeutic targets. Nat Rev Drug Discov 2024:10.1038/s41573-024-00978-5. [PMID: 39014081 DOI: 10.1038/s41573-024-00978-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2024] [Indexed: 07/18/2024]
Abstract
Large-scale cancer genome sequencing studies have revealed that chromatin regulators are frequently mutated in cancer. In particular, more than 20% of cancers harbour mutations in genes that encode subunits of SWI/SNF (BAF) chromatin remodelling complexes. Additional links of SWI/SNF complexes to disease have emerged with the findings that some oncogenes drive transformation by co-opting SWI/SNF function and that germline mutations in select SWI/SNF subunits are the basis of several neurodevelopmental disorders. Other chromatin remodellers, including members of the ISWI, CHD and INO80/SWR complexes, have also been linked to cancer and developmental disorders. Consequently, therapeutic manipulation of SWI/SNF and other remodelling complexes has become of great interest, and drugs that target SWI/SNF subunits have entered clinical trials. Genome-wide perturbation screens in cancer cell lines with SWI/SNF mutations have identified additional synthetic lethal targets and led to further compounds in clinical trials, including one that has progressed to FDA approval. Here, we review the progress in understanding the structure and function of SWI/SNF and other chromatin remodelling complexes, mechanisms by which SWI/SNF mutations cause cancer and neurological diseases, vulnerabilities that arise because of these mutations and efforts to target SWI/SNF complexes and synthetic lethal targets for therapeutic benefit.
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Affiliation(s)
- Hayden A Malone
- Division of Molecular Oncology, Department of Oncology, and Comprehensive Cancer Center, St. Jude Children's Research Hospital, Memphis, TN, USA
- St. Jude Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Charles W M Roberts
- Division of Molecular Oncology, Department of Oncology, and Comprehensive Cancer Center, St. Jude Children's Research Hospital, Memphis, TN, USA.
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2
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Chmykhalo VK, Deev RV, Tokarev AT, Polunina YA, Xue L, Shidlovskii YV. SWI/SNF Complex Connects Signaling and Epigenetic State in Cells of Nervous System. Mol Neurobiol 2024:10.1007/s12035-024-04355-6. [PMID: 39002058 DOI: 10.1007/s12035-024-04355-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 07/06/2024] [Indexed: 07/15/2024]
Abstract
SWI/SNF protein complexes are evolutionarily conserved epigenetic regulators described in all eukaryotes. In metameric animals, the complexes are involved in all processes occurring in the nervous system, from neurogenesis to higher brain functions. On the one hand, the range of roles is wide because the SWI/SNF complexes act universally by mobilizing the nucleosomes in a chromatin template at multiple loci throughout the genome. On the other hand, the complexes mediate the action of multiple signaling pathways that control most aspects of neural tissue development and function. The issues are discussed to provide insight into the molecular basis of the multifaceted role of SWI/SNFs in cell cycle regulation, DNA repair, activation of immediate-early genes, neurogenesis, and brain and connectome formation. An overview is additionally provided for the molecular basis of nervous system pathologies associated with the SWI/SNF complexes and their contribution to neuroinflammation and neurodegeneration. Finally, we discuss the idea that SWI/SNFs act as an integration platform to connect multiple signaling and genetic programs.
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Affiliation(s)
- Victor K Chmykhalo
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St, Moscow, 119334, Russia.
| | - Roman V Deev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St, Moscow, 119334, Russia
| | - Artemiy T Tokarev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St, Moscow, 119334, Russia
| | - Yulia A Polunina
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St, Moscow, 119334, Russia
| | - Lei Xue
- School of Life Science and Technology, The First Rehabilitation Hospital of Shanghai, Tongji University, Shanghai, China
| | - Yulii V Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilova St, Moscow, 119334, Russia
- Department of Biology and General Genetics, Sechenov University, Moscow, Russia
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3
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Chen X, He C, Xu H, Zeng G, Huang Q, Deng Z, Qin X, Shen X, Hu Y. Characterization of the SWI/SNF complex and nucleosome organization in sorghum. FRONTIERS IN PLANT SCIENCE 2024; 15:1430467. [PMID: 38988640 PMCID: PMC11234113 DOI: 10.3389/fpls.2024.1430467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 06/07/2024] [Indexed: 07/12/2024]
Abstract
The switch defective/sucrose non-fermentable (SWI/SNF) multisubunit complex plays an important role in the regulation of gene expression by remodeling chromatin structure. Three SWI/SNF complexes have been identified in Arabidopsis including BAS, SAS, and MAS. Many subunits of these complexes are involved in controlling plant development and stress response. However, the function of these complexes has hardly been studied in other plant species. In this study, we identified the subunits of the SWI/SNF complex in sorghum and analyzed their evolutionary relationships in six grass species. The grass species conserved all the subunits as in Arabidopsis, but gene duplication occurred diversely in different species. Expression pattern analysis in sorghum (Sorghum bicolor) showed that most of the subunit-encoding genes were expressed constitutively, although the expression level was different. Transactivation assays revealed that SbAN3, SbGIF3, and SbSWI3B possessed transactivation activity, which suggests that they may interact with the pre-initiation complex (PIC) to activate transcription. We chose 12 subunits in sorghum to investigate their interaction relationship by yeast two-hybrid assay. We found that these subunits displayed distinct interaction patterns compared to their homologs in Arabidopsis and rice. This suggests that different SWI/SNF complexes may be formed in sorghum to perform chromatin remodeling functions. Through the integrated analysis of MNase-seq and RNA-seq data, we uncovered a positive relationship between gene expression levels and nucleosome phasing. Furthermore, we found differential global nucleosome enrichments between leaves and roots, as well as in response to PEG treatment, suggesting that dynamics of nucleosome occupancy, which is probably mediated by the SWI/SNF complex, may play important roles in sorghum development and stress response.
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Affiliation(s)
- Xiaofei Chen
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Chao He
- National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, China
| | - Huan Xu
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Gongjian Zeng
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Quanjun Huang
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Zhuying Deng
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Xiner Qin
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Xiangling Shen
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Yongfeng Hu
- Hubei Engineering Research Center for Three Gorges Regional Plant Breeding/Biotechnology Research Center, College of Biological and Pharmaceutical Sciences, China Three Gorges University, Yichang, Hubei, China
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4
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Pina C. Contributions of transcriptional noise to leukaemia evolution: KAT2A as a case-study. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230052. [PMID: 38432321 PMCID: PMC10909511 DOI: 10.1098/rstb.2023.0052] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 12/04/2023] [Indexed: 03/05/2024] Open
Abstract
Transcriptional noise is proposed to participate in cell fate changes, but contributions to mammalian cell differentiation systems, including cancer, remain associative. Cancer evolution is driven by genetic variability, with modulatory or contributory participation of epigenetic variants. Accumulation of epigenetic variants enhances transcriptional noise, which can facilitate cancer cell fate transitions. Acute myeloid leukaemia (AML) is an aggressive cancer with strong epigenetic dependencies, characterized by blocked differentiation. It constitutes an attractive model to probe links between transcriptional noise and malignant cell fate regulation. Gcn5/KAT2A is a classical epigenetic transcriptional noise regulator. Its loss increases transcriptional noise and modifies cell fates in stem and AML cells. By reviewing the analysis of KAT2A-depleted pre-leukaemia and leukaemia models, I discuss that the net result of transcriptional noise is diversification of cell fates secondary to alternative transcriptional programmes. Cellular diversification can enable or hinder AML progression, respectively, by differentiation of cell types responsive to mutations, or by maladaptation of leukaemia stem cells. KAT2A-dependent noise-responsive genes participate in ribosome biogenesis and KAT2A loss destabilizes translational activity. I discuss putative contributions of perturbed translation to AML biology, and propose KAT2A loss as a model for mechanistic integration of transcriptional and translational control of noise and fate decisions. This article is part of a discussion meeting issue 'Causes and consequences of stochastic processes in development and disease'.
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Affiliation(s)
- Cristina Pina
- College of Health, Medicine and Life Sciences, Brunel University London, Kingston Lane, Uxbridge, London, UB8 3PH, United Kingdom
- CenGEM – Centre for Genome Engineering and Maintenance, Brunel University London, Kingston Lane, Uxbridge, London, UB8 3PH, United Kingdom
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5
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Nishio H, Kawakatsu T, Yamaguchi N. Beyond heat waves: Unlocking epigenetic heat stress memory in Arabidopsis. PLANT PHYSIOLOGY 2024; 194:1934-1951. [PMID: 37878744 DOI: 10.1093/plphys/kiad558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/25/2023] [Accepted: 10/05/2023] [Indexed: 10/27/2023]
Abstract
Plants remember their exposure to environmental changes and respond more effectively the next time they encounter a similar change by flexibly altering gene expression. Epigenetic mechanisms play a crucial role in establishing such memory of environmental changes and fine-tuning gene expression. With the recent advancements in biochemistry and sequencing technologies, it has become possible to characterize the dynamics of epigenetic changes on scales ranging from short term (minutes) to long term (generations). Here, our main focus is on describing the current understanding of the temporal regulation of histone modifications and chromatin changes during exposure to short-term recurring high temperatures and reevaluating them in the context of natural environments. Investigations of the dynamics of histone modifications and chromatin structural changes in Arabidopsis after repeated exposure to heat at short intervals have revealed the detailed molecular mechanisms of short-term heat stress memory, which include histone modification enzymes, chromatin remodelers, and key transcription factors. In addition, we summarize the spatial regulation of heat responses. Based on the natural temperature patterns during summer, we discuss how plants cope with recurring heat stress occurring at various time intervals by utilizing 2 distinct types of heat stress memory mechanisms. We also explore future research directions to provide a more precise understanding of the epigenetic regulation of heat stress memory.
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Affiliation(s)
- Haruki Nishio
- Data Science and AI Innovation Research Promotion Center, Shiga University, Shiga 522-8522, Japan
- Center for Ecological Research, Kyoto University, Shiga 520-2113, Japan
| | - Taiji Kawakatsu
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8602, Japan
| | - Nobutoshi Yamaguchi
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5, Takayama, Ikoma, Nara 630-0192, Japan
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6
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Candela-Ferre J, Diego-Martin B, Pérez-Alemany J, Gallego-Bartolomé J. Mind the gap: Epigenetic regulation of chromatin accessibility in plants. PLANT PHYSIOLOGY 2024; 194:1998-2016. [PMID: 38236303 PMCID: PMC10980423 DOI: 10.1093/plphys/kiae024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/07/2023] [Accepted: 11/23/2023] [Indexed: 01/19/2024]
Abstract
Chromatin plays a crucial role in genome compaction and is fundamental for regulating multiple nuclear processes. Nucleosomes, the basic building blocks of chromatin, are central in regulating these processes, determining chromatin accessibility by limiting access to DNA for various proteins and acting as important signaling hubs. The association of histones with DNA in nucleosomes and the folding of chromatin into higher-order structures are strongly influenced by a variety of epigenetic marks, including DNA methylation, histone variants, and histone post-translational modifications. Additionally, a wide array of chaperones and ATP-dependent remodelers regulate various aspects of nucleosome biology, including assembly, deposition, and positioning. This review provides an overview of recent advances in our mechanistic understanding of how nucleosomes and chromatin organization are regulated by epigenetic marks and remodelers in plants. Furthermore, we present current technologies for profiling chromatin accessibility and organization.
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Affiliation(s)
- Joan Candela-Ferre
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022Spain
| | - Borja Diego-Martin
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022Spain
| | - Jaime Pérez-Alemany
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022Spain
| | - Javier Gallego-Bartolomé
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022Spain
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7
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Dreier MR, Walia J, de la Serna IL. Targeting SWI/SNF Complexes in Cancer: Pharmacological Approaches and Implications. EPIGENOMES 2024; 8:7. [PMID: 38390898 PMCID: PMC10885108 DOI: 10.3390/epigenomes8010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/28/2024] [Accepted: 01/31/2024] [Indexed: 02/24/2024] Open
Abstract
SWI/SNF enzymes are heterogeneous multi-subunit complexes that utilize the energy from ATP hydrolysis to remodel chromatin structure, facilitating transcription, DNA replication, and repair. In mammalian cells, distinct sub-complexes, including cBAF, ncBAF, and PBAF exhibit varying subunit compositions and have different genomic functions. Alterations in the SWI/SNF complex and sub-complex functions are a prominent feature in cancer, making them attractive targets for therapeutic intervention. Current strategies in cancer therapeutics involve the use of pharmacological agents designed to bind and disrupt the activity of SWI/SNF complexes or specific sub-complexes. Inhibitors targeting the catalytic subunits, SMARCA4/2, and small molecules binding SWI/SNF bromodomains are the primary approaches for suppressing SWI/SNF function. Proteolysis-targeting chimeras (PROTACs) were generated by the covalent linkage of the bromodomain or ATPase-binding ligand to an E3 ligase-binding moiety. This engineered connection promotes the degradation of specific SWI/SNF subunits, enhancing and extending the impact of this pharmacological intervention in some cases. Extensive preclinical studies have underscored the therapeutic potential of these drugs across diverse cancer types. Encouragingly, some of these agents have progressed from preclinical research to clinical trials, indicating a promising stride toward the development of effective cancer therapeutics targeting SWI/SNF complex and sub-complex functions.
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Affiliation(s)
- Megan R Dreier
- Department of Cell and Cancer Biology, University of Toledo College of Medicine and Life Sciences, 3000 Arlington Ave, Toledo 43614, OH, USA
| | - Jasmine Walia
- Department of Cell and Cancer Biology, University of Toledo College of Medicine and Life Sciences, 3000 Arlington Ave, Toledo 43614, OH, USA
| | - Ivana L de la Serna
- Department of Cell and Cancer Biology, University of Toledo College of Medicine and Life Sciences, 3000 Arlington Ave, Toledo 43614, OH, USA
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8
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Lei Y, Yu Y, Fu W, Zhu T, Wu C, Zhang Z, Yu Z, Song X, Xu J, Liang Z, Lü P, Li C. BCL7A and BCL7B potentiate SWI/SNF-complex-mediated chromatin accessibility to regulate gene expression and vegetative phase transition in plants. Nat Commun 2024; 15:935. [PMID: 38296999 PMCID: PMC10830565 DOI: 10.1038/s41467-024-45250-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 01/19/2024] [Indexed: 02/02/2024] Open
Abstract
Switch defective/sucrose non-fermentable (SWI/SNF) chromatin remodeling complexes are multi-subunit machineries that establish and maintain chromatin accessibility and gene expression by regulating chromatin structure. However, how the remodeling activities of SWI/SNF complexes are regulated in eukaryotes remains elusive. B-cell lymphoma/leukemia protein 7 A/B/C (BCL7A/B/C) have been reported as subunits of SWI/SNF complexes for decades in animals and recently in plants; however, the role of BCL7 subunits in SWI/SNF function remains undefined. Here, we identify a unique role for plant BCL7A and BCL7B homologous subunits in potentiating the genome-wide chromatin remodeling activities of SWI/SNF complexes in plants. BCL7A/B require the catalytic ATPase BRAHMA (BRM) to assemble with the signature subunits of the BRM-Associated SWI/SNF complexes (BAS) and for genomic binding at a subset of target genes. Loss of BCL7A and BCL7B diminishes BAS-mediated genome-wide chromatin accessibility without changing the stability and genomic targeting of the BAS complex, highlighting the specialized role of BCL7A/B in regulating remodeling activity. We further show that BCL7A/B fine-tune the remodeling activity of BAS complexes to generate accessible chromatin at the juvenility resetting region (JRR) of the microRNAs MIR156A/C for plant juvenile identity maintenance. In summary, our work uncovers the function of previously elusive SWI/SNF subunits in multicellular eukaryotes and provides insights into the mechanisms whereby plants memorize the juvenile identity through SWI/SNF-mediated control of chromatin accessibility.
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Affiliation(s)
- Yawen Lei
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yaoguang Yu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wei Fu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Tao Zhu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Caihong Wu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhihao Zhang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zewang Yu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xin Song
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Jianqu Xu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhenwei Liang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Peitao Lü
- College of Horticulture, FAFU-UCR Joint Center for Horticultural Biology and Metabolomics, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Chenlong Li
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
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9
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Pelayo MA, Yamaguchi N. Old school, new rules: floral meristem development revealed by 3D gene expression atlases and high-resolution transcription factor-chromatin dynamics. FRONTIERS IN PLANT SCIENCE 2023; 14:1323507. [PMID: 38155851 PMCID: PMC10753784 DOI: 10.3389/fpls.2023.1323507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/23/2023] [Indexed: 12/30/2023]
Abstract
The intricate morphology of the flower is primarily established within floral meristems in which floral organs will be defined and from where the developing flower will emerge. Floral meristem development involves multiscale-level regulation, including lineage and positional mechanisms for establishing cell-type identity, and transcriptional regulation mediated by changes in the chromatin environment. However, many key aspects of floral meristem development remain to be determined, such as: 1) the exact role of cellular location in connecting transcriptional inputs to morphological outcomes, and 2) the precise interactions between transcription factors and chromatin regulators underlying the transcriptional networks that regulate the transition from cell proliferation to differentiation during floral meristem development. Here, we highlight recent studies addressing these points through newly developed spatial reconstruction techniques and high-resolution transcription factor-chromatin environment interactions in the model plant Arabidopsis thaliana. Specifically, we feature studies that reconstructed 3D gene expression atlases of the floral meristem. We also discuss how the precise timing of floral meristem specification, floral organ patterning, and floral meristem termination is determined through temporally defined epigenetic dynamics for fine-tuning of gene expression. These studies offer fresh insights into the well-established principles of floral meristem development and outline the potential for further advances in this field in an age of integrated, powerful, multiscale resolution approaches.
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Affiliation(s)
| | - Nobutoshi Yamaguchi
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara, Japan
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10
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Yan H, Liu F, Zhang G, Liu S, Ma W, Yang T, Li Y, Yang J, Cui H. PlantCHRs: A comprehensive database of plant chromatin remodeling factors. Comput Struct Biotechnol J 2023; 21:4974-4987. [PMID: 37867975 PMCID: PMC10589754 DOI: 10.1016/j.csbj.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/24/2023] Open
Abstract
The Snf2 protein family is a group of ATP-dependent chromatin remodeling factors (CHRs) that play an essential role in gene expression regulation. In plants, Snf2 is involved in growth, development, as well as stress resistance. However, only a very limited number of experimentally validated Snf2 have been identified and reported, while the majority remaining undiscovered in most species . In this study, we predicted 3135 Snf2 proteins and 8398 chromatin remodeling complex (CRC) subunits in diverse plant species, and constructed the Plant Chromatin Remodeling Factors Database (PlantCHRs, http://www.functionalgenomics.cn/PlantCHRs/), which provide a comprehensive resource for researchers to access information about plant CHRs. We also developed an online tool capable of predicting CHRs and CRC subunits. Moreover, we investigated the distribution of Snf2 proteins in different species and observed a significant increase in the number of Snf2 proteins and the diversity of the Snf2 subfamily during the evolution, highlighting their evolutionary importance. By analyzing the expression patterns of the Snf2 genes in different tissues of maize and Arabidopsis, we found that the Snf2 proteins may show some conservation across different species in regulating plant growth and development. Over the all, we established a comprehensive database for plant CHRs, which will facilitate the researches on plant chromatin remodeling.
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Affiliation(s)
- Hengyu Yan
- College of Agronomy, Qingdao Agricultural University, China
| | - Fangyuan Liu
- College of Agronomy, Qingdao Agricultural University, China
| | - Guowei Zhang
- College of Agronomy, Qingdao Agricultural University, China
| | - Shuai Liu
- College of Agronomy, Qingdao Agricultural University, China
| | - Weiwei Ma
- College of Agronomy, Qingdao Agricultural University, China
| | - Ting Yang
- College of Agronomy, Qingdao Agricultural University, China
| | - Yubin Li
- College of Agronomy, Qingdao Agricultural University, China
| | - Jiaotong Yang
- Resource Institute for Chinese and Ethnic Materia Medica, Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Hailong Cui
- College of Economics and Management (Cooperative College), Qingdao Agricultural University, China
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11
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Soto-Castillo JJ, Llavata-Marti L, Fort-Culillas R, Andreu-Cobo P, Moreno R, Codony C, García Del Muro X, Alemany R, Piulats JM, Martin-Liberal J. SWI/SNF Complex Alterations in Tumors with Rhabdoid Features: Novel Therapeutic Approaches and Opportunities for Adoptive Cell Therapy. Int J Mol Sci 2023; 24:11143. [PMID: 37446319 DOI: 10.3390/ijms241311143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/23/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
The SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin-remodeling complex is one of the most remarkably altered epigenetic regulators in cancer. Pathogenic mutations in genes encoding SWI/SNF-related proteins have been recently described in many solid tumors, including rare and aggressive malignancies with rhabdoid features with no standard therapies in advanced or metastatic settings. In recent years, clinical trials with targeted drugs aimed at restoring its function have shown discouraging results. However, preclinical data have found an association between these epigenetic alterations and response to immune therapy. Thus, the rationale for immunotherapy strategies in SWI/SNF complex alteration-related tumors is strong. Here, we review the SWI/SNF complex and how its dysfunction drives the oncogenesis of rhabdoid tumors and the proposed strategies to revert this alteration and promising novel therapeutic approaches, including immune checkpoint inhibition and adoptive cell therapy.
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Affiliation(s)
- Juan José Soto-Castillo
- Medical Oncology Department, Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
| | - Lucía Llavata-Marti
- Medical Oncology Department, Catalan Institute of Oncology (ICO), 17007 Girona, Spain
| | - Roser Fort-Culillas
- Medical Oncology Department, Catalan Institute of Oncology (ICO), 17007 Girona, Spain
| | - Pablo Andreu-Cobo
- Medical Oncology Department, Parc Tauli Hospital Universitari, 08208 Sabadell, Spain
| | - Rafael Moreno
- Cancer Immunotherapy Group, iPROCURE Program, Bellvitge Biomedical Research Institute (IDIBELL), Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
| | - Carles Codony
- Cancer Immunotherapy Group, iPROCURE Program, Bellvitge Biomedical Research Institute (IDIBELL), Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
| | - Xavier García Del Muro
- Medical Oncology Department, Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
| | - Ramon Alemany
- Cancer Immunotherapy Group, iPROCURE Program, Bellvitge Biomedical Research Institute (IDIBELL), Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
| | - Josep M Piulats
- Medical Oncology Department, Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
- Cancer Immunotherapy Group, iPROCURE Program, Bellvitge Biomedical Research Institute (IDIBELL), Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
| | - Juan Martin-Liberal
- Medical Oncology Department, Catalan Institute of Oncology (ICO), 08908 Hospitalet de Llobregat, Spain
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Fu W, Yu Y, Shu J, Yu Z, Zhong Y, Zhu T, Zhang Z, Liang Z, Cui Y, Chen C, Li C. Organization, genomic targeting, and assembly of three distinct SWI/SNF chromatin remodeling complexes in Arabidopsis. THE PLANT CELL 2023; 35:2464-2483. [PMID: 37062961 PMCID: PMC10291025 DOI: 10.1093/plcell/koad111] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/21/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
Switch defective/sucrose nonfermentable (SWI/SNF) complexes are evolutionarily conserved multisubunit machines that play vital roles in chromatin architecture regulation for modulating gene expression via sliding or ejection of nucleosomes in eukaryotes. In plants, perturbations of SWI/SNF subunits often result in severe developmental disorders. However, the subunit composition, pathways of assembly, and genomic targeting of the plant SWI/SNF complexes are poorly understood. Here, we report the organization, genomic targeting, and assembly of 3 distinct SWI/SNF complexes in Arabidopsis thaliana: BRAHMA-Associated SWI/SNF complexes (BAS), SPLAYED-Associated SWI/SNF complexes (SAS), and MINUSCULE-Associated SWI/SNF complexes (MAS). We show that BAS complexes are equivalent to human ncBAF, whereas SAS and MAS complexes evolve in multiple subunits unique to plants, suggesting plant-specific functional evolution of SWI/SNF complexes. We further show overlapping and specific genomic targeting of the 3 plant SWI/SNF complexes on chromatin and reveal that SAS complexes are necessary for the correct genomic localization of the BAS complexes. Finally, we define the role of the core module subunit in the assembly of plant SWI/SNF complexes and highlight that ATPase module subunit is required for global complex stability and the interaction of core module subunits in Arabidopsis SAS and BAS complexes. Together, our work highlights the divergence of SWI/SNF chromatin remodelers during eukaryote evolution and provides a comprehensive landscape for understanding plant SWI/SNF complex organization, assembly, genomic targeting, and function.
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Affiliation(s)
- Wei Fu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yaoguang Yu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Jie Shu
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong 510650, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Zewang Yu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yixiong Zhong
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Tao Zhu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhihao Zhang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhenwei Liang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yuhai Cui
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario, Canada N5V 4T3
| | - Chen Chen
- Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong 510650, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Chenlong Li
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
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Ma T, Wang S, Sun C, Tian J, Guo H, Cui S, Zhao H. Arabidopsis LFR, a SWI/SNF complex component, interacts with ICE1 and activates ICE1 and CBF3 expression in cold acclimation. FRONTIERS IN PLANT SCIENCE 2023; 14:1097158. [PMID: 37025149 PMCID: PMC10070696 DOI: 10.3389/fpls.2023.1097158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 03/08/2023] [Indexed: 06/19/2023]
Abstract
Low temperatures restrict the growth and geographic distribution of plants, as well as crop yields. Appropriate transcriptional regulation is critical for cold acclimation in plants. In this study, we found that the mutation of Leaf and flower related (LFR), a component of SWI/SNF chromatin remodeling complex (CRC) important for transcriptional regulation in Arabidopsis (Arabidopsis thaliana), resulted in hypersensitivity to freezing stress in plants with or without cold acclimation, and this defect was successfully complemented by LFR. The expression levels of CBFs and COR genes in cold-treated lfr-1 mutant plants were lower than those in wild-type plants. Furthermore, LFR was found to interact directly with ICE1 in yeast and plants. Consistent with this, LFR was able to directly bind to the promoter region of CBF3, a direct target of ICE1. LFR was also able to bind to ICE1 chromatin and was required for ICE1 transcription. Together, these results demonstrate that LFR interacts directly with ICE1 and activates ICE1 and CBF3 gene expression in response to cold stress. Our work enhances our understanding of the epigenetic regulation of cold responses in plants.
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BRM Complex in Arabidopsis Adopts ncBAF-like Composition and Requires BRD Subunits for Assembly and Stability. Int J Mol Sci 2023; 24:ijms24043917. [PMID: 36835328 PMCID: PMC9967331 DOI: 10.3390/ijms24043917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 02/12/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
ATP-dependent SWI/SNF chromatin remodelling complexes are conserved multi-subunit assemblies that control genome activity. Functions of SWI/SNF complexes in plant development and growth have been well established, but the architecture of particular assemblies is unclear. In this study, we elucidate the organization of Arabidopsis SWI/SNF complexes formed around a BRM catalytic subunit, and define the requirement of bromodomain-containing proteins BRD1/2/13 for the formation and stability of the entire complex. Using affinity purification followed by mass spectrometry, we identify a set of BRM-associated subunits and demonstrate that the BRM complexes strongly resemble mammalian non-canonical BAF complexes. Furthermore, we identify BDH1 and 2 proteins as components of the BRM complex and, using mutant analyses, show that BDH1/2 are important for vegetative and generative development, as well as hormonal responses. We further show that BRD1/2/13 represent unique subunits of the BRM complexes, and their depletion severely affects the integrity of the complex, resulting in the formation of residual assemblies. Finally, analyses of BRM complexes after proteasome inhibition revealed the existence of a module consisting of the ATPase, ARP, and BDH proteins, assembled with other subunits in a BRD-dependent manner. Together, our results suggest modular organization of plant SWI/SNF complexes and provide a biochemical explanation for mutant phenotypes.
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Guo J, Cai G, Li YQ, Zhang YX, Su YN, Yuan DY, Zhang ZC, Liu ZZ, Cai XW, Guo J, Li L, Chen S, He XJ. Comprehensive characterization of three classes of Arabidopsis SWI/SNF chromatin remodelling complexes. NATURE PLANTS 2022; 8:1423-1439. [PMID: 36471048 DOI: 10.1038/s41477-022-01282-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 10/19/2022] [Indexed: 05/12/2023]
Abstract
Although SWI/SNF chromatin remodelling complexes are known to regulate diverse biological functions in plants, the classification, compositions and functional mechanisms of the complexes remain to be determined. Here we comprehensively characterized SWI/SNF complexes by affinity purification and mass spectrometry in Arabidopsis thaliana, and found three classes of SWI/SNF complexes, which we termed BAS, SAS and MAS (BRM-, SYD- and MINU1/2-associated SWI/SNF complexes). By investigating multiple developmental phenotypes of SWI/SNF mutants, we found that three classes of SWI/SNF complexes have both overlapping and specific functions in regulating development. To investigate how the three classes of SWI/SNF complexes differentially regulate development, we mapped different SWI/SNF components on chromatin at the whole-genome level and determined their effects on chromatin accessibility. While all three classes of SWI/SNF complexes regulate chromatin accessibility at proximal promoter regions, SAS is a major SWI/SNF complex that is responsible for mediating chromatin accessibility at distal promoter regions and intergenic regions. Histone modifications are related to both the association of SWI/SNF complexes with chromatin and the SWI/SNF-dependent chromatin accessibility. Three classes of SWI/SNF-dependent accessibility may enable different sets of transcription factors to access chromatin. These findings lay a foundation for further investigation of the function of three classes of SWI/SNF complexes in plants.
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Affiliation(s)
- Jing Guo
- College of Life Sciences, Beijing Normal University, Beijing, China
- National Institute of Biological Sciences, Beijing, China
| | - Guang Cai
- National Institute of Biological Sciences, Beijing, China
| | - Yong-Qiang Li
- National Institute of Biological Sciences, Beijing, China
| | - Yi-Xuan Zhang
- National Institute of Biological Sciences, Beijing, China
| | - Yin-Na Su
- National Institute of Biological Sciences, Beijing, China
| | - Dan-Yang Yuan
- National Institute of Biological Sciences, Beijing, China
| | | | - Zhen-Zhen Liu
- National Institute of Biological Sciences, Beijing, China
| | - Xue-Wei Cai
- National Institute of Biological Sciences, Beijing, China
| | - Jing Guo
- National Institute of Biological Sciences, Beijing, China
| | - Lin Li
- National Institute of Biological Sciences, Beijing, China
| | - She Chen
- National Institute of Biological Sciences, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
| | - Xin-Jian He
- National Institute of Biological Sciences, Beijing, China.
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China.
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Diego-Martin B, Pérez-Alemany J, Candela-Ferre J, Corbalán-Acedo A, Pereyra J, Alabadí D, Jami-Alahmadi Y, Wohlschlegel J, Gallego-Bartolomé J. The TRIPLE PHD FINGERS proteins are required for SWI/SNF complex-mediated +1 nucleosome positioning and transcription start site determination in Arabidopsis. Nucleic Acids Res 2022; 50:10399-10417. [PMID: 36189880 PMCID: PMC9561266 DOI: 10.1093/nar/gkac826] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 09/08/2022] [Accepted: 09/16/2022] [Indexed: 11/14/2022] Open
Abstract
Eukaryotes have evolved multiple ATP-dependent chromatin remodelers to shape the nucleosome landscape. We recently uncovered an evolutionarily conserved SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeler complex in plants reminiscent of the mammalian BAF subclass, which specifically incorporates the MINUSCULE (MINU) catalytic subunits and the TRIPLE PHD FINGERS (TPF) signature subunits. Here we report experimental evidence that establishes the functional relevance of TPF proteins for the complex activity. Our results show that depletion of TPF triggers similar pleiotropic phenotypes and molecular defects to those found in minu mutants. Moreover, we report the genomic location of MINU2 and TPF proteins as representative members of this SWI/SNF complex and their impact on nucleosome positioning and transcription. These analyses unravel the binding of the complex to thousands of genes where it modulates the position of the +1 nucleosome. These targets tend to produce 5′-shifted transcripts in the tpf and minu mutants pointing to the participation of the complex in alternative transcription start site usage. Interestingly, there is a remarkable correlation between +1 nucleosome shift and 5′ transcript length change suggesting their functional connection. In summary, this study unravels the function of a plant SWI/SNF complex involved in +1 nucleosome positioning and transcription start site determination.
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Affiliation(s)
- Borja Diego-Martin
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
| | - Jaime Pérez-Alemany
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
| | - Joan Candela-Ferre
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
| | - Antonio Corbalán-Acedo
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
| | - Juan Pereyra
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
| | - David Alabadí
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
| | - Yasaman Jami-Alahmadi
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - James Wohlschlegel
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Javier Gallego-Bartolomé
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universitat Politècnica de València, Valencia, 46022, Spain
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Cooper GW, Hong AL. SMARCB1-Deficient Cancers: Novel Molecular Insights and Therapeutic Vulnerabilities. Cancers (Basel) 2022; 14:cancers14153645. [PMID: 35892904 PMCID: PMC9332782 DOI: 10.3390/cancers14153645] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 07/20/2022] [Accepted: 07/20/2022] [Indexed: 12/27/2022] Open
Abstract
Simple Summary Loss of SMARCB1 has been identified as the sole mutation in a number of rare pediatric and adult cancers, most of which have a poor prognosis despite intensive therapies including surgery, radiation, and chemotherapy. Thus, a more robust understanding of the mechanisms driving this set of cancers is vital to improving patient treatment and outcomes. This review outlines recent advances made in our understanding of the function of SMARCB1 and how these advances have been used to discover putative therapeutic vulnerabilities. Abstract SMARCB1 is a critical component of the BAF complex that is responsible for global chromatin remodeling. Loss of SMARCB1 has been implicated in the initiation of cancers such as malignant rhabdoid tumor (MRT), atypical teratoid rhabdoid tumor (ATRT), and, more recently, renal medullary carcinoma (RMC). These SMARCB1-deficient tumors have remarkably stable genomes, offering unique insights into the epigenetic mechanisms in cancer biology. Given the lack of druggable targets and the high mortality associated with SMARCB1-deficient tumors, a significant research effort has been directed toward understanding the mechanisms of tumor transformation and proliferation. Accumulating evidence suggests that tumorigenicity arises from aberrant enhancer and promoter regulation followed by dysfunctional transcriptional control. In this review, we outline key mechanisms by which loss of SMARCB1 may lead to tumor formation and cover how these mechanisms have been used for the design of targeted therapy.
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Affiliation(s)
- Garrett W. Cooper
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Andrew L. Hong
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA;
- Aflac Cancer and Blood Disorders Center, Children’s Healthcare of Atlanta, Atlanta, GA 30322, USA
- Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA
- Correspondence:
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