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Green NM, Talbot D, Tootle TL. Nuclear actin is a critical regulator of Drosophila female germline stem cell maintenance. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.27.609996. [PMID: 39253513 PMCID: PMC11383290 DOI: 10.1101/2024.08.27.609996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
Nuclear actin has been implicated in regulating cell fate, differentiation, and cellular reprogramming. However, its roles in development and tissue homeostasis remain largely unknown. Here we uncover the role of nuclear actin in regulating stemness using Drosophila ovarian germline stem cells (GSCs) as a model. We find that the localization and structure of nuclear actin is dynamic in the early germ cells. Nuclear actin recognized by anti-actin C4 is found in both the nucleoplasm and nucleolus of GSCs. The polymeric nucleoplasmic C4 pool is lost after the 2-cell stage, whereas the monomeric nucleolar pool persists to the 8-cell stage, suggesting that polymeric nuclear actin may contribute to stemness. To test this idea, we overexpressed nuclear targeted actin constructs to alter nuclear actin polymerization states in the GSCs and early germ cells. Increasing monomeric nuclear actin, but not polymerizable nuclear actin, causes GSC loss that ultimately results in germline loss. This GSC loss is rescued by simultaneous overexpression of monomeric and polymerizable nuclear actin. Together these data reveal that GSC maintenance requires polymeric nuclear actin. This polymeric nuclear actin likely plays numerous roles in the GSCs, as increasing monomeric nuclear actin disrupts nuclear architecture causing nucleolar hypertrophy, distortion of the nuclear lamina, and heterochromatin reorganization; all factors critical for GSC maintenance and function. These data provide the first evidence that nuclear actin, and in particular, its ability to polymerize, are critical for stem cell function and tissue homeostasis in vivo.
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Affiliation(s)
- Nicole M. Green
- Anatomy and Cell Biology, University of Iowa Carver College of Medicine, 51 Newton Rd, 1-500 BSB, Iowa City, IA 52242
- Current affiliation: Biology, Cornell College, 600 First Street SW, Mount Vernon, IA 52314
| | - Danielle Talbot
- Anatomy and Cell Biology, University of Iowa Carver College of Medicine, 51 Newton Rd, 1-500 BSB, Iowa City, IA 52242
- Current affiliation: Biology, University of Iowa, 129 E. Jefferson St, 246 BB, Iowa City, IA 52242
| | - Tina L. Tootle
- Anatomy and Cell Biology, University of Iowa Carver College of Medicine, 51 Newton Rd, 1-500 BSB, Iowa City, IA 52242
- Current affiliation: Biology, University of Iowa, 129 E. Jefferson St, 246 BB, Iowa City, IA 52242
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2
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Signal B, Phipps AJ, Giles KA, Huskins SN, Mercer TR, Robinson MD, Woodhouse A, Taberlay PC. Ageing-Related Changes to H3K4me3, H3K27ac, and H3K27me3 in Purified Mouse Neurons. Cells 2024; 13:1393. [PMID: 39195281 DOI: 10.3390/cells13161393] [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: 07/09/2024] [Revised: 08/19/2024] [Accepted: 08/19/2024] [Indexed: 08/29/2024] Open
Abstract
Neurons are central to lifelong learning and memory, but ageing disrupts their morphology and function, leading to cognitive decline. Although epigenetic mechanisms are known to play crucial roles in learning and memory, neuron-specific genome-wide epigenetic maps into old age remain scarce, often being limited to whole-brain homogenates and confounded by glial cells. Here, we mapped H3K4me3, H3K27ac, and H3K27me3 in mouse neurons across their lifespan. This revealed stable H3K4me3 and global losses of H3K27ac and H3K27me3 into old age. We observed patterns of synaptic function gene deactivation, regulated through the loss of the active mark H3K27ac, but not H3K4me3. Alongside this, embryonic development loci lost repressive H3K27me3 in old age. This suggests a loss of a highly refined neuronal cellular identity linked to global chromatin reconfiguration. Collectively, these findings indicate a key role for epigenetic regulation in neurons that is inextricably linked with ageing.
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Affiliation(s)
- Brandon Signal
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000, Australia
| | - Andrew J Phipps
- Wicking Dementia Research and Education Centre, College of Health and Medicine, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000, Australia
| | - Katherine A Giles
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000, Australia
- Children's Medical Research Institute, University of Sydney, 214 Hawkesbury Road, Westmead, NSW 2145, Australia
| | - Shannon N Huskins
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000, Australia
| | - Timothy R Mercer
- Australian Institute for Bioengineering and Nanotechnology, Corner College and Cooper Roads, Brisbane, QLD 4072, Australia
| | - Mark D Robinson
- SIB Swiss Institute of Bioinformatics, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Adele Woodhouse
- Wicking Dementia Research and Education Centre, College of Health and Medicine, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000, Australia
| | - Phillippa C Taberlay
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool Street, Hobart, TAS 7000, Australia
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3
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Sundby LJ, Southern WM, Sun J, Patrinostro X, Zhang W, Yong J, Ervasti JM. Deletion of exons 2 and 3 from Actb and cell immortalization lead to widespread, β-actin independent alterations in gene expression associated with cell cycle control. Eur J Cell Biol 2024; 103:151397. [PMID: 38387258 DOI: 10.1016/j.ejcb.2024.151397] [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: 10/29/2023] [Revised: 02/11/2024] [Accepted: 02/12/2024] [Indexed: 02/24/2024] Open
Abstract
The cytoplasmic actin proteins, β- and γ-actin, are 99% identical but thought to perform non-redundant functions. The nucleotide coding regions of cytoplasmic actin genes, Actb and Actg1, are 89% identical. Knockout (KO) of Actb by Cre-mediated deletion of first coding exons 2 and 3 in mice is embryonic lethal and fibroblasts derived from KO embryos (MEFs) fail to proliferate. In contrast, Actg1 KO MEFs display with a much milder defect in cell proliferation and Actg1 KO mice are viable, but present with increased perinatal lethality. Recent studies have identified important protein-independent functions for both Actb and Actg1 and demonstrate that deletions within the Actb nucleotide sequence, and not loss of the β-actin protein, cause the most severe phenotypes in KO mice and cells. Here, we use a multi-omics approach to better understand what drives the phenotypes of Actb KO MEFs. RNA-sequencing and mass spectrometry reveal largescale changes to the transcriptome, proteome, and phosphoproteome in cells lacking Actb but not those only lacking β-actin protein. Pathway analysis of genes and proteins differentially expressed upon Actb KO suggest widespread dysregulation of genes involved in the cell cycle that may explain the severe defect in proliferation.
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Affiliation(s)
- Lauren J Sundby
- Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota, Minneapolis, MN 55455, USA
| | - William M Southern
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jiao Sun
- Department of Computer Science, University of Central Florida, Orlando, FL 32816, USA
| | - Xiaobai Patrinostro
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Wei Zhang
- Department of Computer Science, University of Central Florida, Orlando, FL 32816, USA
| | - Jeongsik Yong
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - James M Ervasti
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
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4
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Vivo M, Rosti V, Cervone S, Lanzuolo C. Chromatin plasticity in mechanotransduction. Curr Opin Cell Biol 2024; 88:102376. [PMID: 38810318 DOI: 10.1016/j.ceb.2024.102376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/24/2024] [Accepted: 05/07/2024] [Indexed: 05/31/2024]
Abstract
Living organisms can detect and respond to physical forces at the cellular level. The pathways that transmit these forces to the nucleus allow cells to react quickly and consistently to environmental changes. Mechanobiology involves the interaction between physical forces and biological processes and is crucial for driving embryonic development and adapting to environmental cues during adulthood. Molecular studies have shown that cells can sense mechanical signals directly through membrane receptors linked to the cytoskeleton or indirectly through biochemical cascades that can influence gene expression for environmental adaptation. This review will explore the role of epigenetic modifications, emphasizing the 3D genome architecture and nuclear structures as responders to mechanical stimuli, which ensure cellular memory and adaptability. Understanding how mechanical cues are transduced and regulate cell functioning, governing processes such as cell programming and reprogramming, is essential for advancing our knowledge of human diseases.
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Affiliation(s)
- Maria Vivo
- Università degli Studi di Salerno, Fisciano, Italy.
| | - Valentina Rosti
- Institute of Biomedical Technologies, National Research Council (CNR), Milan, Italy; INGM Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Sara Cervone
- INGM Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Chiara Lanzuolo
- Institute of Biomedical Technologies, National Research Council (CNR), Milan, Italy; INGM Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy.
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5
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Gourisankar S, Krokhotin A, Wenderski W, Crabtree GR. Context-specific functions of chromatin remodellers in development and disease. Nat Rev Genet 2024; 25:340-361. [PMID: 38001317 DOI: 10.1038/s41576-023-00666-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2023] [Indexed: 11/26/2023]
Abstract
Chromatin remodellers were once thought to be highly redundant and nonspecific in their actions. However, recent human genetic studies demonstrate remarkable biological specificity and dosage sensitivity of the thirty-two adenosine triphosphate (ATP)-dependent chromatin remodellers encoded in the human genome. Mutations in remodellers produce many human developmental disorders and cancers, motivating efforts to investigate their distinct functions in biologically relevant settings. Exquisitely specific biological functions seem to be an emergent property in mammals, and in many cases are based on the combinatorial assembly of subunits and the generation of stable, composite surfaces. Critical interactions between remodelling complex subunits, the nucleosome and other transcriptional regulators are now being defined from structural and biochemical studies. In addition, in vivo analyses of remodellers at relevant genetic loci have provided minute-by-minute insights into their dynamics. These studies are proposing new models for the determinants of remodeller localization and function on chromatin.
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Affiliation(s)
- Sai Gourisankar
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Andrey Krokhotin
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of Developmental Biology, Stanford University, Stanford, CA, USA
| | - Wendy Wenderski
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of Developmental Biology, Stanford University, Stanford, CA, USA
| | - Gerald R Crabtree
- Department of Pathology, Stanford University, Stanford, CA, USA.
- Department of Developmental Biology, Stanford University, Stanford, CA, USA.
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6
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Ulferts S, Lopes M, Miyamoto K, Grosse R. Nuclear actin dynamics and functions at a glance. J Cell Sci 2024; 137:jcs261630. [PMID: 38563209 DOI: 10.1242/jcs.261630] [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] [Indexed: 04/04/2024] Open
Abstract
Actin is well known for its cytoskeletal functions, where it helps to control and maintain cell shape and architecture, as well as regulating cell migration and intracellular cargo transport, among others. However, actin is also prevalent in the nucleus, where genome-regulating roles have been described, including it being part of chromatin-remodeling complexes. More recently, with the help of advances in microscopy techniques and specialized imaging probes, direct visualization of nuclear actin filament dynamics has helped elucidate new roles for nuclear actin, such as in cell cycle regulation, DNA replication and repair, chromatin organization and transcriptional condensate formation. In this Cell Science at a Glance article, we summarize the known signaling events driving the dynamic assembly of actin into filaments of various structures within the nuclear compartment for essential genome functions. Additionally, we highlight the physiological role of nuclear F-actin in meiosis and early embryonic development.
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Affiliation(s)
- Svenja Ulferts
- Institute for Clinical and Experimental Pharmacology and Toxicology I, Medical Faculty, University of Freiburg, 79104 Freiburg, Germany
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, 8057 Zurich, Switzerland
| | - Kei Miyamoto
- Faculty of Biology-Oriented Science and Technology, Kindai University, Wakayama 649-6493, Japan
| | - Robert Grosse
- Institute for Clinical and Experimental Pharmacology and Toxicology I, Medical Faculty, University of Freiburg, 79104 Freiburg, Germany
- Centre for Integrative Biological Signalling Studies (CIBSS), 79104 Freiburg, Germany
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7
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Kwartler CS, Pedroza AJ, Kaw A, Guan P, Ma S, Duan XY, Kernell C, Wang C, Pinelo JEE, Bowen MSB, Chen J, Zhong Y, Sinha S, Shen X, Fischbein MP, Milewicz DM. Nuclear Smooth Muscle α-actin Participates in Vascular Smooth Muscle Cell Differentiation. NATURE CARDIOVASCULAR RESEARCH 2023; 2:937-955. [PMID: 38919852 PMCID: PMC11198982 DOI: 10.1038/s44161-023-00337-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/23/2023] [Indexed: 06/27/2024]
Abstract
Missense variants throughout ACTA2, encoding smooth muscle α-actin (αSMA), predispose to adult-onset thoracic aortic disease, but variants disrupting arginine 179 (R179) lead to Smooth Muscle Dysfunction Syndrome (SMDS) characterized by diverse childhood-onset vascular diseases. Here we show that αSMA localizes to the nucleus in wildtype (WT) smooth muscle cells (SMCs), enriches in the nucleus with SMC differentiation, and associates with chromatin remodeling complexes and SMC contractile gene promotors. The ACTA2 p.R179 αSMA variant shows decreased nuclear localization. Primary SMCs from Acta2 SMC-R179C/+ mice are less differentiated than WT SMCs in vitro and in vivo and have global changes in chromatin accessibility. Induced pluripotent stem cells from patients with ACTA2 p.R179 variants fail to fully differentiate from neuroectodermal progenitor cells to SMCs, and single-cell transcriptomic analyses of an ACTA2 p.R179H patient's aortic tissue show increased SMC plasticity. Thus, nuclear αSMA participates in SMC differentiation, and loss of this nuclear activity occurs with ACTA2 p.R179 pathogenic variants.
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Affiliation(s)
- Callie S. Kwartler
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Albert J. Pedroza
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA 94305
| | - Anita Kaw
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Pujun Guan
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Shuangtao Ma
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
- Current address: Department Medicine, Michigan State University, East Lansing, MI 48824
| | - Xue-yan Duan
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Caroline Kernell
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Charis Wang
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Jose Emiliano Esparza Pinelo
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Mikayla S. Borthwick Bowen
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Jiyuan Chen
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Yuan Zhong
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, TX 78957
| | - Sanjay Sinha
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Xuetong Shen
- Institute of Cancer Research, Shenzhen Bay Laboratory, Shenzhen, China
| | | | - Dianna M. Milewicz
- Division of Medical Genetics, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030
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8
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Jeruzalska E, Mazur AJ. The Role of non-muscle actin paralogs in cell cycle progression and proliferation. Eur J Cell Biol 2023; 102:151315. [PMID: 37099935 DOI: 10.1016/j.ejcb.2023.151315] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 04/14/2023] [Accepted: 04/17/2023] [Indexed: 04/28/2023] Open
Abstract
Uncontrolled cell proliferation leads to several pathologies, including cancer. Thus, this process must be tightly regulated. The cell cycle accounts for cell proliferation, and its progression is coordinated with changes in cell shape, for which cytoskeleton reorganization is responsible. Rearrangement of the cytoskeleton allows for its participation in the precise division of genetic material and cytokinesis. One of the main cytoskeletal components is filamentous actin-based structures. Mammalian cells have at least six actin paralogs, four of which are muscle-specific, while two, named β- and γ-actin, are abundantly present in all types of cells. This review summarizes the findings that establish the role of non-muscle actin paralogs in regulating cell cycle progression and proliferation. We discuss studies showing that the level of a given non-muscle actin paralog in a cell influences the cell's ability to progress through the cell cycle and, thus, proliferation. Moreover, we elaborate on the non-muscle actins' role in regulating gene transcription, interactions of actin paralogs with proteins involved in controlling cell proliferation, and the contribution of non-muscle actins to different structures in a dividing cell. The data cited in this review show that non-muscle actins regulate the cell cycle and proliferation through varying mechanisms. We point to the need for further studies addressing these mechanisms.
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Affiliation(s)
- Estera Jeruzalska
- Department of Cell Pathology, Faculty of Biotechnology, University of Wroclaw, Poland
| | - Antonina J Mazur
- Department of Cell Pathology, Faculty of Biotechnology, University of Wroclaw, Poland.
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9
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Sadler KC. Epigenetics across the evolutionary tree: New paradigms from non-model animals. Bioessays 2023; 45:e2200036. [PMID: 36403219 DOI: 10.1002/bies.202200036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 10/28/2022] [Accepted: 11/03/2022] [Indexed: 11/21/2022]
Abstract
All animals have evolved solutions to manage their genomes, enabling the efficient organization of meters of DNA strands in the nucleus and allowing for nuanced regulation of gene expression while keeping transposable elements suppressed. Epigenetic modifications are central to accomplishing all these. Recent advances in sequencing technologies and the development of techniques that profile epigenetic marks and chromatin accessibility using reagents that can be used in any species has catapulted epigenomic studies in diverse animal species, shedding light on the multitude of epigenomic mechanisms utilized across the evolutionary tree. Now, comparative epigenomics is a rapidly growing field that is uncovering mechanistic aspects of epigenetic modifications and chromatin organization in non-model invertebrates, ranging from octopus to sponges. This review puts recent discoveries in the epigenetics of non-model invertebrates in historical context, and describes new insight into the patterning and functions of DNA methylation and other highly conserved epigenetic modifications.
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Affiliation(s)
- Kirsten C Sadler
- Program in Biology, New York University, Abu Dhabi, United Arab Emirates
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10
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Aversano S, Caiazza C, Caiazzo M. Induced pluripotent stem cell-derived and directly reprogrammed neurons to study neurodegenerative diseases: The impact of aging signatures. Front Aging Neurosci 2022; 14:1069482. [PMID: 36620769 PMCID: PMC9810544 DOI: 10.3389/fnagi.2022.1069482] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
Many diseases of the central nervous system are age-associated and do not directly result from genetic mutations. These include late-onset neurodegenerative diseases (NDDs), which represent a challenge for biomedical research and drug development due to the impossibility to access to viable human brain specimens. Advancements in reprogramming technologies have allowed to obtain neurons from induced pluripotent stem cells (iPSCs) or directly from somatic cells (iNs), leading to the generation of better models to understand the molecular mechanisms and design of new drugs. Nevertheless, iPSC technology faces some limitations due to reprogramming-associated cellular rejuvenation which resets the aging hallmarks of donor cells. Given the prominent role of aging for the development and manifestation of late-onset NDDs, this suggests that this approach is not the most suitable to accurately model age-related diseases. Direct neuronal reprogramming, by which a neuron is formed via direct conversion from a somatic cell without going through a pluripotent intermediate stage, allows the possibility to generate patient-derived neurons that maintain aging and epigenetic signatures of the donor. This aspect may be advantageous for investigating the role of aging in neurodegeneration and for finely dissecting underlying pathological mechanisms. Here, we will compare iPSC and iN models as regards the aging status and explore how this difference is reported to affect the phenotype of NDD in vitro models.
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Affiliation(s)
- Simona Aversano
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Carmen Caiazza
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Massimiliano Caiazzo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy,Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, Netherlands,*Correspondence: Massimiliano Caiazzo,
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11
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Zhou J, Corvaisier M, Malycheva D, Alvarado-Kristensson M. Hubbing the Cancer Cell. Cancers (Basel) 2022; 14:5924. [PMID: 36497405 PMCID: PMC9738523 DOI: 10.3390/cancers14235924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/24/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
Oncogenic transformation drives adaptive changes in a growing tumor that affect the cellular organization of cancerous cells, resulting in the loss of specialized cellular functions in the polarized compartmentalization of cells. The resulting altered metabolic and morphological patterns are used clinically as diagnostic markers. This review recapitulates the known functions of actin, microtubules and the γ-tubulin meshwork in orchestrating cell metabolism and functional cellular asymmetry.
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Affiliation(s)
| | | | | | - Maria Alvarado-Kristensson
- Molecular Pathology, Department of Translational Medicine, Skåne University Hospital Malmö 1, Lund University, 20502 Malmö, Sweden
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12
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Tomikawa J, Miyamoto K. Structural alteration of the nucleus for the reprogramming of gene expression. FEBS J 2022; 289:7221-7233. [PMID: 33891358 DOI: 10.1111/febs.15894] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/06/2021] [Accepted: 04/19/2021] [Indexed: 01/13/2023]
Abstract
The regulation of gene expression is a critical process for establishing and maintaining cellular identity. Gene expression is controlled through a chromatin-based mechanism in the nucleus of eukaryotic cells. Recent studies suggest that chromatin accessibility and the higher-order structure of chromatin affect transcriptional outcome. This is especially evident when cells change their fate during development and nuclear reprogramming. Furthermore, non-chromosomal contents of the cell nucleus, namely nucleoskeleton proteins, can also affect chromatin and nuclear structures, resulting in transcriptional alterations. Here, we review our current mechanistic understanding about how chromatin and nuclear structures impact transcription in the course of embryonic development, cellular differentiation and nuclear reprogramming, and also discuss unresolved questions that remain to be addressed in the field.
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Affiliation(s)
- Junko Tomikawa
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Wakayama, Japan
| | - Kei Miyamoto
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Wakayama, Japan
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13
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Regulation of nuclear actin levels and MRTF/SRF target gene expression during PC6.3 cell differentiation. Exp Cell Res 2022; 420:113356. [PMID: 36122768 DOI: 10.1016/j.yexcr.2022.113356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/25/2022] [Accepted: 09/11/2022] [Indexed: 11/20/2022]
Abstract
Actin has important functions in both cytoplasm and nucleus of the cell, with active nuclear transport mechanisms maintaining the cellular actin balance. Nuclear actin levels are subject to regulation during many cellular processes from cell differentiation to cancer. Here we show that nuclear actin levels increase upon differentiation of PC6.3 cells towards neuron-like cells. Photobleaching experiments demonstrate that this increase is due to decreased nuclear export of actin during cell differentiation. Increased nuclear actin levels lead to decreased nuclear localization of MRTF-A, a well-established transcription cofactor of SRF. In line with MRTF-A localization, transcriptomics analysis reveals that MRTF/SRF target gene expression is first transiently activated, but then substantially downregulated during PC6.3 cell differentiation. This study therefore describes a novel cellular context, where regulation of nuclear actin is utilized to tune MRTF/SRF target gene expression during cell differentiation.
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14
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Nakamura T, Iwata M, Hamano M, Eguchi R, Takeshita JI, Yamanishi Y. Small compound-based direct cell conversion with combinatorial optimization of pathway regulations. Bioinformatics 2022; 38:ii99-ii105. [PMID: 36124791 DOI: 10.1093/bioinformatics/btac475] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
MOTIVATION Direct cell conversion, direct reprogramming (DR), is an innovative technology that directly converts source cells to target cells without bypassing induced pluripotent stem cells. The use of small compounds (e.g. drugs) for DR can help avoid carcinogenic risk induced by gene transfection; however, experimentally identifying small compounds remains challenging because of combinatorial explosion. RESULTS In this article, we present a new computational method, COMPRENDRE (combinatorial optimization of pathway regulations for direct reprograming), to elucidate the mechanism of small compound-based DR and predict new combinations of small compounds for DR. We estimated the potential target proteins of DR-inducing small compounds and identified a set of target pathways involving DR. We identified multiple DR-related pathways that have not previously been reported to induce neurons or cardiomyocytes from fibroblasts. To overcome the problem of combinatorial explosion, we developed a variant of a simulated annealing algorithm to identify the best set of compounds that can regulate DR-related pathways. Consequently, the proposed method enabled to predict new DR-inducing candidate combinations with fewer compounds and to successfully reproduce experimentally verified compounds inducing the direct conversion from fibroblasts to neurons or cardiomyocytes. The proposed method is expected to be useful for practical applications in regenerative medicine. AVAILABILITY AND IMPLEMENTATION The code supporting the current study is available at the http://labo.bio.kyutech.ac.jp/~yamani/comprendre. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Toru Nakamura
- Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
| | - Michio Iwata
- Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
| | - Momoko Hamano
- Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
| | - Ryohei Eguchi
- Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
| | - Jun-Ichi Takeshita
- Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8569, Japan
| | - Yoshihiro Yamanishi
- Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
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15
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Gunasekaran S, Miyagawa Y, Miyamoto K. Actin nucleoskeleton in embryonic development and cellular differentiation. Curr Opin Cell Biol 2022; 76:102100. [DOI: 10.1016/j.ceb.2022.102100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/28/2022] [Accepted: 04/22/2022] [Indexed: 11/03/2022]
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16
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Dupont S, Wickström SA. Mechanical regulation of chromatin and transcription. Nat Rev Genet 2022; 23:624-643. [DOI: 10.1038/s41576-022-00493-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2022] [Indexed: 01/14/2023]
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17
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Mahmood SR, El Said NH, Percipalle P. The Role of Nuclear Actin in Genome Organization and Gene Expression Regulation During Differentiation. Results Probl Cell Differ 2022; 70:607-624. [PMID: 36348124 DOI: 10.1007/978-3-031-06573-6_22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In the cell nucleus, actin participates in numerous essential processes. Actin is involved in chromatin as part of specific ATP-dependent chromatin remodeling complexes and associates with the RNA polymerase machinery to regulate transcription at multiple levels. Emerging evidence has also shown that the nuclear actin pool controls the architecture of the mammalian genome playing an important role in its hierarchical organization into transcriptionally active and repressed compartments, contributing to the clustering of RNA polymerase II into transcriptional hubs. Here, we review the most recent literature and discuss how actin involvement in genome organization impacts the regulation of gene programs that are activated or repressed during differentiation and development. As in the cytoplasm, we propose that nuclear actin is involved in key nuclear tasks in complex with different types of actin-binding proteins that regulate actin function and bridge interactions between actin and various nuclear components.
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Affiliation(s)
- Syed Raza Mahmood
- Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
- Department of Biology, New York University, New York, NY, USA
| | - Nadine Hosny El Said
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - Piergiorgio Percipalle
- Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
- Department of Biology, New York University, New York, NY, USA.
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.
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18
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Napoletano F, Ferrari Bravo G, Voto IAP, Santin A, Celora L, Campaner E, Dezi C, Bertossi A, Valentino E, Santorsola M, Rustighi A, Fajner V, Maspero E, Ansaloni F, Cancila V, Valenti CF, Santo M, Artimagnella OB, Finaurini S, Gioia U, Polo S, Sanges R, Tripodo C, Mallamaci A, Gustincich S, d'Adda di Fagagna F, Mantovani F, Specchia V, Del Sal G. The prolyl-isomerase PIN1 is essential for nuclear Lamin-B structure and function and protects heterochromatin under mechanical stress. Cell Rep 2021; 36:109694. [PMID: 34525372 DOI: 10.1016/j.celrep.2021.109694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 06/29/2021] [Accepted: 08/19/2021] [Indexed: 01/24/2023] Open
Abstract
Chromatin organization plays a crucial role in tissue homeostasis. Heterochromatin relaxation and consequent unscheduled mobilization of transposable elements (TEs) are emerging as key contributors of aging and aging-related pathologies, including Alzheimer's disease (AD) and cancer. However, the mechanisms governing heterochromatin maintenance or its relaxation in pathological conditions remain poorly understood. Here we show that PIN1, the only phosphorylation-specific cis/trans prolyl isomerase, whose loss is associated with premature aging and AD, is essential to preserve heterochromatin. We demonstrate that this PIN1 function is conserved from Drosophila to humans and prevents TE mobilization-dependent neurodegeneration and cognitive defects. Mechanistically, PIN1 maintains nuclear type-B Lamin structure and anchoring function for heterochromatin protein 1α (HP1α). This mechanism prevents nuclear envelope alterations and heterochromatin relaxation under mechanical stress, which is a key contributor to aging-related pathologies.
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Affiliation(s)
- Francesco Napoletano
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy.
| | - Gloria Ferrari Bravo
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Ilaria Anna Pia Voto
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Aurora Santin
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Lucia Celora
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Elena Campaner
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Clara Dezi
- Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Arianna Bertossi
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Elena Valentino
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy
| | - Mariangela Santorsola
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Alessandra Rustighi
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | | | - Elena Maspero
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy
| | - Federico Ansaloni
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Valeria Cancila
- Tumor Immunology Unit, Department of Health Science, Human Pathology Section, School of Medicine, University of Palermo, 90133 Palermo, Italy
| | - Cesare Fabio Valenti
- Tumor Immunology Unit, Department of Health Science, Human Pathology Section, School of Medicine, University of Palermo, 90133 Palermo, Italy
| | - Manuela Santo
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | | | - Sara Finaurini
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Ubaldo Gioia
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy
| | - Simona Polo
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy
| | - Remo Sanges
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Claudio Tripodo
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy; Tumor Immunology Unit, Department of Health Science, Human Pathology Section, School of Medicine, University of Palermo, 90133 Palermo, Italy
| | - Antonello Mallamaci
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy
| | - Stefano Gustincich
- Area of Neuroscience, International School for Advanced Studies (SISSA), 34146 Trieste, Italy; Central RNA Laboratory, Italian Institute of Technology, 16163 Genova, Italy
| | - Fabrizio d'Adda di Fagagna
- FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy; Institute of Molecular Genetics, National Research Institute (CNR), Pavia, Italy
| | - Fiamma Mantovani
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy
| | - Valeria Specchia
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, 73100 Lecce, Italy
| | - Giannino Del Sal
- Laboratorio Nazionale CIB (LNCIB), Area Science Park, Padriciano 99, 34149 Trieste, Italy; Department of Life Sciences (DSV), University of Trieste, 34127 Trieste, Italy; FIRC Institute of Molecular Oncology (IFOM), 20139 Milan, Italy.
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19
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β-actin dependent chromatin remodeling mediates compartment level changes in 3D genome architecture. Nat Commun 2021; 12:5240. [PMID: 34475390 PMCID: PMC8413440 DOI: 10.1038/s41467-021-25596-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 08/18/2021] [Indexed: 02/07/2023] Open
Abstract
β-actin is a crucial component of several chromatin remodeling complexes that control chromatin structure and accessibility. The mammalian Brahma-associated factor (BAF) is one such complex that plays essential roles in development and differentiation by regulating the chromatin state of critical genes and opposing the repressive activity of polycomb repressive complexes (PRCs). While previous work has shown that β-actin loss can lead to extensive changes in gene expression and heterochromatin organization, it is not known if changes in β-actin levels can directly influence chromatin remodeling activities of BAF and polycomb proteins. Here we conduct a comprehensive genomic analysis of β-actin knockout mouse embryonic fibroblasts (MEFs) using ATAC-Seq, HiC-seq, RNA-Seq and ChIP-Seq of various epigenetic marks. We demonstrate that β-actin levels can induce changes in chromatin structure by affecting the complex interplay between chromatin remodelers such as BAF/BRG1 and EZH2. Our results show that changes in β-actin levels and associated chromatin remodeling activities can not only impact local chromatin accessibility but also induce reversible changes in 3D genome architecture. Our findings reveal that β-actin-dependent chromatin remodeling plays a role in shaping the chromatin landscape and influences the regulation of genes involved in development and differentiation.
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20
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Record J, Saeed MB, Venit T, Percipalle P, Westerberg LS. Journey to the Center of the Cell: Cytoplasmic and Nuclear Actin in Immune Cell Functions. Front Cell Dev Biol 2021; 9:682294. [PMID: 34422807 PMCID: PMC8375500 DOI: 10.3389/fcell.2021.682294] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/06/2021] [Indexed: 12/12/2022] Open
Abstract
Actin cytoskeletal dynamics drive cellular shape changes, linking numerous cell functions to physiological and pathological cues. Mutations in actin regulators that are differentially expressed or enriched in immune cells cause severe human diseases known as primary immunodeficiencies underscoring the importance of efficienct actin remodeling in immune cell homeostasis. Here we discuss recent findings on how immune cells sense the mechanical properties of their environement. Moreover, while the organization and biochemical regulation of cytoplasmic actin have been extensively studied, nuclear actin reorganization is a rapidly emerging field that has only begun to be explored in immune cells. Based on the critical and multifaceted contributions of cytoplasmic actin in immune cell functionality, nuclear actin regulation is anticipated to have a large impact on our understanding of immune cell development and functionality.
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Affiliation(s)
- Julien Record
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Mezida B. Saeed
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Tomas Venit
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - Piergiorgio Percipalle
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Lisa S. Westerberg
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
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21
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Azar J, Bahmad HF, Daher D, Moubarak MM, Hadadeh O, Monzer A, Al Bitar S, Jamal M, Al-Sayegh M, Abou-Kheir W. The Use of Stem Cell-Derived Organoids in Disease Modeling: An Update. Int J Mol Sci 2021; 22:7667. [PMID: 34299287 PMCID: PMC8303386 DOI: 10.3390/ijms22147667] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 02/06/2023] Open
Abstract
Organoids represent one of the most important advancements in the field of stem cells during the past decade. They are three-dimensional in vitro culturing models that originate from self-organizing stem cells and can mimic the in vivo structural and functional specificities of body organs. Organoids have been established from multiple adult tissues as well as pluripotent stem cells and have recently become a powerful tool for studying development and diseases in vitro, drug screening, and host-microbe interaction. The use of stem cells-that have self-renewal capacity to proliferate and differentiate into specialized cell types-for organoids culturing represents a major advancement in biomedical research. Indeed, this new technology has a great potential to be used in a multitude of fields, including cancer research, hereditary and infectious diseases. Nevertheless, organoid culturing is still rife with many challenges, not limited to being costly and time consuming, having variable rates of efficiency in generation and maintenance, genetic stability, and clinical applications. In this review, we aim to provide a synopsis of pluripotent stem cell-derived organoids and their use for disease modeling and other clinical applications.
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Affiliation(s)
- Joseph Azar
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
| | - Hisham F. Bahmad
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
- Arkadi M. Rywlin M.D. Department of Pathology and Laboratory Medicine, Mount Sinai Medical Center, Miami Beach, FL 33140, USA
| | - Darine Daher
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
| | - Maya M. Moubarak
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
| | - Ola Hadadeh
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
| | - Alissar Monzer
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
| | - Samar Al Bitar
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
| | - Mohamed Jamal
- Hamdan Bin Mohammed College of Dental Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai 66566, United Arab Emirates
| | - Mohamed Al-Sayegh
- Biology Division, New York University Abu Dhabi, Abu Dhabi 2460, United Arab Emirates
| | - Wassim Abou-Kheir
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut 1107 2260, Lebanon; (J.A.); (H.F.B.); (D.D.); (M.M.M.); (O.H.); (A.M.); (S.A.B.)
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22
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Venit T, El Said NH, Mahmood SR, Percipalle P. A dynamic actin-dependent nucleoskeleton and cell identity. J Biochem 2021; 169:243-257. [PMID: 33351909 DOI: 10.1093/jb/mvaa133] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 10/27/2020] [Indexed: 12/19/2022] Open
Abstract
Actin is an essential regulator of cellular functions. In the eukaryotic cell nucleus, actin regulates chromatin as a bona fide component of chromatin remodelling complexes, it associates with nuclear RNA polymerases to regulate transcription and is involved in co-transcriptional assembly of nascent RNAs into ribonucleoprotein complexes. Actin dynamics are, therefore, emerging as a major regulatory factor affecting diverse cellular processes. Importantly, the involvement of actin dynamics in nuclear functions is redefining the concept of nucleoskeleton from a rigid scaffold to a dynamic entity that is likely linked to the three-dimensional organization of the nuclear genome. In this review, we discuss how nuclear actin, by regulating chromatin structure through phase separation may contribute to the architecture of the nuclear genome during cell differentiation and facilitate the expression of specific gene programs. We focus specifically on mitochondrial genes and how their dysregulation in the absence of actin raises important questions about the role of cytoskeletal proteins in regulating chromatin structure. The discovery of a novel pool of mitochondrial actin that serves as 'mitoskeleton' to facilitate organization of mtDNA supports a general role for actin in genome architecture and a possible function of distinct actin pools in the communication between nucleus and mitochondria.
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Affiliation(s)
- Tomas Venit
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), PO Box 129188, Abu Dhabi United Arab Emirates
| | - Nadine Hosny El Said
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), PO Box 129188, Abu Dhabi United Arab Emirates
| | - Syed Raza Mahmood
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), PO Box 129188, Abu Dhabi United Arab Emirates.,Department of Biology, New York University, 100 Washington Square East, 1009 Silver Center, New York, NY 10003, USA
| | - Piergiorgio Percipalle
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), PO Box 129188, Abu Dhabi United Arab Emirates.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrhenius väg 20C, 114 18 Stockholm, Sweden
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23
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Machida N, Takahashi D, Ueno Y, Nakama Y, Gubeli RJ, Bertoldo D, Harata M. Modulating dynamics and function of nuclear actin with synthetic bicyclic peptides. J Biochem 2021; 169:295-302. [PMID: 33169153 DOI: 10.1093/jb/mvaa130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 10/26/2020] [Indexed: 12/27/2022] Open
Abstract
Actin exists in monomeric globular (G-) and polymerized filamentous (F-) forms and the dynamics of its polymerization/depolymerization are tightly regulated in both the cytoplasm and the nucleus. Various essential functions of nuclear actin have been identified including regulation of gene expression and involvement in the repair of DNA double-strand breaks (DSB). Small G-actin-binding molecules affect F-actin formation and can be utilized for analysis and manipulation of actin in living cells. However, these G-actin-binding molecules are obtained by extraction from natural sources or through complex chemical synthesis procedures, and therefore, the generation of their derivatives for analytical tools is underdeveloped. In addition, their effects on nuclear actin cannot be separately evaluated from those on cytoplasmic actin. Previously, we have generated synthetic bicyclic peptides, consisting of two macrocyclic rings, which bind to G-actin but not to F-actin. Here, we describe the introduction of these bicyclic peptides into living cells. Furthermore, by conjugation to a nuclear localization signal (NLS), the bicyclic peptides accumulated in the nucleus. The NLS-bicyclic peptides repress the formation of nuclear F-actin, and impair transcriptional regulation and DSB repair. These observations highlight a potential role for NLS-linked bicyclic peptides in the manipulation of dynamics and functions of nuclear actin.
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Affiliation(s)
- Nanako Machida
- Laboratory of Molecular Biology, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 468-1, Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Daisuke Takahashi
- Laboratory of Molecular Biology, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 468-1, Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Yuya Ueno
- Laboratory of Molecular Biology, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 468-1, Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Yoshihiro Nakama
- Laboratory of Molecular Biology, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 468-1, Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Raphael J Gubeli
- Institute of Chemical Sciences and Engineering, School of Basic Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Davide Bertoldo
- Institute of Chemical Sciences and Engineering, School of Basic Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Masahiko Harata
- Laboratory of Molecular Biology, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 468-1, Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
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24
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Miyamoto K, Harata M. Nucleoskeleton proteins for nuclear dynamics. J Biochem 2021; 169:237-241. [PMID: 33479767 DOI: 10.1093/jb/mvab006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 12/29/2020] [Indexed: 12/12/2022] Open
Abstract
The eukaryotic nucleus shows organized structures of chromosomes, transcriptional components and their associated proteins. It has been believed that such a dense nuclear environment prevents the formation of a cytoskeleton-like network of protein filaments. However, accumulating evidence suggests that the cell nucleus also possesses structural filamentous components to support nuclear organization and compartments, which are referred to as nucleoskeleton proteins. Nucleoskeleton proteins including lamins and actin influence nuclear dynamics including transcriptional regulation, chromatin organization and DNA damage responses. Furthermore, these nucleoskeleton proteins play a pivotal role in cellular differentiation and animal development. In this commentary, we discuss how nucleoskeleton-based regulatory mechanisms orchestrate nuclear dynamics.
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Affiliation(s)
- Kei Miyamoto
- Graduate School of Biology-Oriented Science and Technology, Kindai University, 930 Nishimitani, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Masahiko Harata
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Aramaki Aza-Aoba 468-1, Aoba-ku, Sendai 980-0845, Japan
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25
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Vasan L, Park E, David LA, Fleming T, Schuurmans C. Direct Neuronal Reprogramming: Bridging the Gap Between Basic Science and Clinical Application. Front Cell Dev Biol 2021; 9:681087. [PMID: 34291049 PMCID: PMC8287587 DOI: 10.3389/fcell.2021.681087] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/02/2021] [Indexed: 12/15/2022] Open
Abstract
Direct neuronal reprogramming is an innovative new technology that involves the conversion of somatic cells to induced neurons (iNs) without passing through a pluripotent state. The capacity to make new neurons in the brain, which previously was not achievable, has created great excitement in the field as it has opened the door for the potential treatment of incurable neurodegenerative diseases and brain injuries such as stroke. These neurological disorders are associated with frank neuronal loss, and as new neurons are not made in most of the adult brain, treatment options are limited. Developmental biologists have paved the way for the field of direct neuronal reprogramming by identifying both intrinsic cues, primarily transcription factors (TFs) and miRNAs, and extrinsic cues, including growth factors and other signaling molecules, that induce neurogenesis and specify neuronal subtype identities in the embryonic brain. The striking observation that postmitotic, terminally differentiated somatic cells can be converted to iNs by mis-expression of TFs or miRNAs involved in neural lineage development, and/or by exposure to growth factors or small molecule cocktails that recapitulate the signaling environment of the developing brain, has opened the door to the rapid expansion of new neuronal reprogramming methodologies. Furthermore, the more recent applications of neuronal lineage conversion strategies that target resident glial cells in situ has expanded the clinical potential of direct neuronal reprogramming techniques. Herein, we present an overview of the history, accomplishments, and therapeutic potential of direct neuronal reprogramming as revealed over the last two decades.
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Affiliation(s)
- Lakshmy Vasan
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Eunjee Park
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Luke Ajay David
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Taylor Fleming
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
| | - Carol Schuurmans
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
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26
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Takahashi Y, Hiratsuka S, Machida N, Takahashi D, Matsushita J, Hozak P, Misteli T, Miyamoto K, Harata M. Impairment of nuclear F-actin formation and its relevance to cellular phenotypes in Hutchinson-Gilford progeria syndrome. Nucleus 2021; 11:250-263. [PMID: 32954953 PMCID: PMC7529414 DOI: 10.1080/19491034.2020.1815395] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging disorder caused by a mutation of lamin A, which contributes to nuclear architecture and the spatial organization of chromatin in the nucleus. The expression of a lamin A mutant, named progerin, leads to functional and structural disruption of nuclear organization. Since progerin lacks a part of the actin-binding site of lamin A, we hypothesized that nuclear actin dynamics and function are altered in HGPS cells. Nuclear F-actin is required for the organization of nuclear shape, transcriptional regulation, DNA damage repair, and activation of Wnt/β-catenin signaling. Here we show that the expression of progerin decreases nuclear F-actin and impairs F-actin-regulated transcription. When nuclear F-actin levels are increased by overexpression of nuclear-targeted actin or by using jasplakinolide, a compound that stabilizes F-actin, the irregularity of nuclear shape and defects in gene expression can be reversed. These observations provide evidence for a novel relationship between nuclear actin and the etiology of HGPS.
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Affiliation(s)
- Yuto Takahashi
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University , Sendai, Japan
| | - Shogo Hiratsuka
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University , Sendai, Japan
| | - Nanako Machida
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University , Sendai, Japan
| | - Daisuke Takahashi
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University , Sendai, Japan
| | - Junpei Matsushita
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University , Sendai, Japan
| | - Pavel Hozak
- Institute of Molecular Genetics of the Czech Academy of Sciences , Prague, Czech Republic
| | - Tom Misteli
- National Cancer Institute, National Institutes of Health , Bethesda, MD, USA
| | - Kei Miyamoto
- Laboratory of Molecular Developmental Biology, Faculty of Biology-Oriented Science and Technology, Kindai University , Wakayama, Japan
| | - Masahiko Harata
- Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University , Sendai, Japan
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27
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Okuno T, Li WY, Hatano Y, Takasu A, Sakamoto Y, Yamamoto M, Ikeda Z, Shindo T, Plessner M, Morita K, Matsumoto K, Yamagata K, Grosse R, Miyamoto K. Zygotic Nuclear F-Actin Safeguards Embryonic Development. Cell Rep 2021; 31:107824. [PMID: 32610125 DOI: 10.1016/j.celrep.2020.107824] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 02/27/2020] [Accepted: 06/04/2020] [Indexed: 12/20/2022] Open
Abstract
After fertilization, sperm and oocyte nuclei are rapidly remodeled to form swollen pronuclei (PN) in mammalian zygotes, and the proper formation and function of PN are key to producing totipotent zygotes. However, how mature PN are formed has been unclear. We find that filamentous actin (F-actin) assembles in the PN of mouse zygotes and is required for fully functional PN. The perturbation of nuclear actin dynamics in zygotes results in the misregulation of genes related to genome integrity and abnormal development of mouse embryos. We show that nuclear F-actin ensures DNA damage repair, thus preventing the activation of a zygotic checkpoint. Furthermore, optogenetic control of cofilin nuclear localization reveals the dynamically regulated F-actin nucleoskeleton in zygotes, and its timely disassembly is needed for developmental progression. Nuclear F-actin is a hallmark of totipotent zygotic PN, and the temporal regulation of its polymerized state is necessary for normal embryonic development.
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Affiliation(s)
- Tomomi Okuno
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Wayne Yang Li
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Yu Hatano
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Atsushi Takasu
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Yuko Sakamoto
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Mari Yamamoto
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Zenki Ikeda
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Taiki Shindo
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Matthias Plessner
- Institute of Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-University Freiburg, Albertstrasse 25, 79104 Freiburg, Germany
| | - Kohtaro Morita
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Kazuya Matsumoto
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Kazuo Yamagata
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan
| | - Robert Grosse
- Institute of Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-University Freiburg, Albertstrasse 25, 79104 Freiburg, Germany; CIBSS-Centre for Integrative Biological Signalling Studies, Albert-Ludwigs-University Freiburg, Schänzlestr. 18, 79104 Freiburg, Germany
| | - Kei Miyamoto
- Graduate School of Biology-Oriented Science and Technology, Kindai University, Kinokawa-shi, Wakayama 649-6493, Japan.
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28
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Ulferts S, Prajapati B, Grosse R, Vartiainen MK. Emerging Properties and Functions of Actin and Actin Filaments Inside the Nucleus. Cold Spring Harb Perspect Biol 2021; 13:cshperspect.a040121. [PMID: 33288541 PMCID: PMC7919393 DOI: 10.1101/cshperspect.a040121] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Recent years have provided considerable insights into the dynamic nature of the cell nucleus, which is constantly reorganizing its genome, controlling its size and shape, as well as spatiotemporally orchestrating chromatin remodeling and transcription. Remarkably, it has become clear that the ancient and highly conserved cytoskeletal protein actin plays a crucial part in these processes. However, the underlying mechanisms, regulations, and properties of actin functions inside the nucleus are still not well understood. Here we summarize the diverse and distinct roles of monomeric and filamentous actin as well as the emerging roles for actin dynamics inside the nuclear compartment for genome organization and nuclear architecture.
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Affiliation(s)
- Svenja Ulferts
- Institute for Clinical and Experimental Pharmacology and Toxicology I, University of Freiburg, 79104 Freiburg, Germany
| | - Bina Prajapati
- Institute of Biotechnology, Helsinki Institute for Life Science, University of Helsinki, 00014 Helsinki, Finland
| | - Robert Grosse
- Institute for Clinical and Experimental Pharmacology and Toxicology I, University of Freiburg, 79104 Freiburg, Germany,Centre for Integrative Biological Signalling Studies (CIBSS), 79104 Freiburg, Germany
| | - Maria K. Vartiainen
- Institute of Biotechnology, Helsinki Institute for Life Science, University of Helsinki, 00014 Helsinki, Finland
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29
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Xie X, Mahmood SR, Gjorgjieva T, Percipalle P. Emerging roles of cytoskeletal proteins in regulating gene expression and genome organization during differentiation. Nucleus 2020; 11:53-65. [PMID: 32212905 PMCID: PMC7289583 DOI: 10.1080/19491034.2020.1742066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In the eukaryotic cell nucleus, cytoskeletal proteins are emerging as essential players in nuclear function. In particular, actin regulates chromatin as part of ATP-dependent chromatin remodeling complexes, it modulates transcription and it is incorporated into nascent ribonucleoprotein complexes, accompanying them from the site of transcription to polyribosomes. The nuclear actin pool is undistinguishable from the cytoplasmic one in terms of its ability to undergo polymerization and it has also been implicated in the dynamics of chromatin, regulating heterochromatin segregation at the nuclear lamina and maintaining heterochromatin levels in the nuclear interiors. One of the next frontiers is, therefore, to determine a possible involvement of nuclear actin in the functional architecture of the cell nucleus by regulating the hierarchical organization of chromatin and, thus, genome organization. Here, we discuss the repertoire of these potential actin functions and how they are likely to play a role in the context of cellular differentiation.
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Affiliation(s)
- Xin Xie
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - S Raza Mahmood
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.,Department of Biology, New York University, New York, NY, USA
| | - Tamara Gjorgjieva
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - Piergiorgio Percipalle
- Science Division, Biology Program, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
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30
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Gjorgjieva T, Xie X, Commins P, Pasricha R, Mahmood SR, Gunsalus KC, Naumov P, Percipalle P. Loss of β-Actin Leads to Accelerated Mineralization and Dysregulation of Osteoblast-Differentiation Genes during Osteogenic Reprogramming. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2002261. [PMID: 33304760 PMCID: PMC7709978 DOI: 10.1002/advs.202002261] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/29/2020] [Indexed: 06/12/2023]
Abstract
Actin plays fundamental roles in both the cytoplasm and the cell nucleus. In the nucleus, β-actin regulates neuronal reprogramming by consolidating a heterochromatin landscape required for transcription of neuronal gene programs, yet it remains unknown whether it has a role in other differentiation models. To explore the potential roles of β-actin in osteogenesis, β-actin wild-type (WT) and β-actin knockout (KO) mouse embryonic fibroblasts (MEFs) are reprogrammed to osteoblast-like cells using small molecules in vitro. It is discovered that loss of β-actin leads to an accelerated mineralization phenotype (hypermineralization), accompanied with enhanced formation of extracellular hydroxyapatite microcrystals, which originate in the mitochondria in the form of microgranules. This phenotype is a consequence of rapid upregulation of mitochondrial genes including those involved in oxidative phosphorylation (OXPHOS) in reprogrammed KO cells. It is further found that osteogenic gene programs are differentially regulated between WT and KO cells, with clusters of genes exhibiting different temporal expression patterns. A novel function for β-actin in osteogenic reprogramming through a mitochondria-based mechanism that controls cell-mediated mineralization is proposed.
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Affiliation(s)
- Tamara Gjorgjieva
- Program in BiologyDivision of Science and MathematicsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
| | - Xin Xie
- Program in BiologyDivision of Science and MathematicsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
- Center for Genomics and Systems BiologyNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
| | - Patrick Commins
- Program in ChemistryDivision of Science and MathematicsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
| | - Renu Pasricha
- Core Technology PlatformsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
| | - Syed Raza Mahmood
- Program in BiologyDivision of Science and MathematicsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
- Department of BiologyNew York UniversityNew YorkNY10003USA
| | - Kristin C. Gunsalus
- Center for Genomics and Systems BiologyNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
- Department of BiologyNew York UniversityNew YorkNY10003USA
| | - Panče Naumov
- Program in ChemistryDivision of Science and MathematicsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
| | - Piergiorgio Percipalle
- Program in BiologyDivision of Science and MathematicsNew York University Abu Dhabi (NYUAD)P.O. Box 129188Abu DhabiUnited Arab Emirates
- Department of Molecular BiosciencesThe Wenner‐Gren InstituteStockholm UniversityStockholmSE‐106 91Sweden
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31
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Al-Sayegh MA, Mahmood SR, Khair SBA, Xie X, El Gindi M, Kim T, Almansoori A, Percipalle P. β-actin contributes to open chromatin for activation of the adipogenic pioneer factor CEBPA during transcriptional reprograming. Mol Biol Cell 2020; 31:2511-2521. [PMID: 32877276 PMCID: PMC7851876 DOI: 10.1091/mbc.e19-11-0628] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Adipogenesis is regulated by a cascade of signals that drive transcriptional reprogramming in adipocytes. Here, we report that nuclear actin regulates the chromatin states that establish tissue- specific expression during adipogenesis. To study the role of β-actin in adipocyte differentiation, we conducted RNA sequencing on wild-type and β-actin knockout mouse embryonic fibroblasts (MEFs) after reprograming to adipocytes. We found that β-actin depletion affects induction of several adipogenic genes during transcriptional reprograming. This impaired regulation of adipogenic genes is linked to reduced expression of the pioneer factor Cebpa and is rescued by reintroducing NLS-tagged β-actin. ATAC-Seq in knockout MEFs revealed that actin-dependent reduction of Cebpa expression correlates with decreased chromatin accessibility and loss of chromatin association of the ATPase Brg1. This, in turn, impairs CEBPB's association with its Cebpa promoter-proximal binding site during adipogenesis. We propose a role for the nuclear β-actin pool in maintaining open chromatin for transcriptional reprogramming during adipogenic differentiation.
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Affiliation(s)
- M A Al-Sayegh
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - S R Mahmood
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.,Department of Biology, New York University, New York, NY 10003
| | - S B Abul Khair
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - X Xie
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - M El Gindi
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - T Kim
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - A Almansoori
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates
| | - P Percipalle
- Biology Program, Science Division, New York University Abu Dhabi (NYUAD), Abu Dhabi, United Arab Emirates.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
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32
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Nuclear actin dynamics in gene expression and genome organization. Semin Cell Dev Biol 2020; 102:105-112. [DOI: 10.1016/j.semcdb.2019.10.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/28/2019] [Accepted: 10/24/2019] [Indexed: 11/19/2022]
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33
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Bullock SL, Visa N, Pederson T. Meeting report - Nuclear and cytoplasmic molecular machines at work. J Cell Sci 2020; 133:133/7/jcs245134. [PMID: 32253357 DOI: 10.1242/jcs.245134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This report summarizes an international conference on molecular machines convened at New York University, Abu Dhabi by Piergiorgio Percipalle, George Shubeita and Serdal Kirmizialtin. The meeting was conceived around the epistemological question of what do we understand, or not understand (if we have open minds), about the degree to which cells operate by the individual actions of single enzymes or non-catalytic protein effectors, versus combinations of these in which their heterotypic association creates an entity that is more finely tuned and efficient - a machine. This theme was explored through a vivid series of talks, summarizing the latest findings on macromolecular complexes that operate in the nucleus or cytoplasm.
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Affiliation(s)
| | - Neus Visa
- Department of Molecular Biosciences, Wenner Gren Institute, Stockholm University, Stockholm 10 691, Sweden
| | - Thoru Pederson
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
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34
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Nuclear myosin 1 activates p21 gene transcription in response to DNA damage through a chromatin-based mechanism. Commun Biol 2020; 3:115. [PMID: 32161327 PMCID: PMC7066169 DOI: 10.1038/s42003-020-0836-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 02/18/2020] [Indexed: 12/20/2022] Open
Abstract
Nuclear myosin 1 (NM1) has been implicated in key nuclear functions. Together with actin, it has been shown to initiate and regulate transcription, it is part of the chromatin remodeling complex B-WICH, and is responsible for rearrangements of chromosomal territories in response to external stimuli. Here we show that deletion of NM1 in mouse embryonic fibroblasts leads to chromatin and transcription dysregulation affecting the expression of DNA damage and cell cycle genes. NM1 KO cells exhibit increased DNA damage and changes in cell cycle progression, proliferation, and apoptosis, compatible with a phenotype resulting from impaired p53 signaling. We show that upon DNA damage, NM1 forms a complex with p53 and activates the expression of checkpoint regulator p21 (Cdkn1A) by PCAF and Set1 recruitment to its promoter for histone H3 acetylation and methylation. We propose a role for NM1 in the transcriptional response to DNA damage response and maintenance of genome stability. Venit et al. demonstrate a role for Nuclear myosin 1 (NM1) in the DNA Damage Response by affecting the expression of the p53 target, p21, through chromatin remodeling. They used embryonic fibroblasts from mouse model, high content phenotypic profiling and cell assays, RNA-Seq and ChIP-Seq and pull-down assays and show that NM1 is required for the recruitment of PCAF and SET1 to the p21 gene in response to etoposide.
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35
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Hyrskyluoto A, Vartiainen MK. Regulation of nuclear actin dynamics in development and disease. Curr Opin Cell Biol 2020; 64:18-24. [PMID: 32088545 DOI: 10.1016/j.ceb.2020.01.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/17/2020] [Accepted: 01/22/2020] [Indexed: 12/21/2022]
Abstract
Actin has essential functions both in the cytoplasm and in the nucleus, where it has been linked to key nuclear processes, from transcription to DNA damage response. The multifunctional nature of actin suggests that the cell must contain mechanisms to accurately control the cellular actin balance. Indeed, recent results have demonstrated that nuclear actin levels fluctuate to regulate the transcriptional activity of the cell and that controlled nuclear actin polymerization is required for transcription activation, cell cycle progression, and DNA repair. Intriguingly, aberrant nuclear actin regulation has been observed, for example, in cancer, signifying the importance of this process for cellular homeostasis. This review discussed the latest research on how nuclear actin is regulated, and how this influences actin-dependent nuclear processes.
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Affiliation(s)
- Alise Hyrskyluoto
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, 00014, Helsinki, Finland
| | - Maria K Vartiainen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, 00014, Helsinki, Finland.
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36
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Percipalle P, Vartiainen M. Cytoskeletal proteins in the cell nucleus: a special nuclear actin perspective. Mol Biol Cell 2020; 30:1781-1785. [PMID: 31306096 PMCID: PMC6727747 DOI: 10.1091/mbc.e18-10-0645] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The emerging role of cytoskeletal proteins in the cell nucleus has become a new frontier in cell biology. Actin and actin-binding proteins regulate chromatin and gene expression, but importantly they are beginning to be essential players in genome organization. These actin-based functions contribute to genome stability and integrity while affecting DNA replication and global transcription patterns. This is likely to occur through interactions of actin with nuclear components including nuclear lamina and subnuclear organelles. An exciting future challenge is to understand how these actin-based genome-wide mechanisms may regulate development and differentiation by interfering with the mechanical properties of the cell nucleus and how regulated actin polymerization plays a role in maintaining nuclear architecture. With a special focus on actin, here we summarize how cytoskeletal proteins operate in the nucleus and how they may be important to consolidate nuclear architecture for sustained gene expression or silencing.
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Affiliation(s)
- Piergiorgio Percipalle
- Biology Program, Science Division, New York University Abu Dhabi, 12988 Abu Dhabi, United Arab Emirates.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Maria Vartiainen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, 00014 Helsinki, Finland
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37
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Venit T, Mahmood SR, Endara-Coll M, Percipalle P. Nuclear actin and myosin in chromatin regulation and maintenance of genome integrity. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 355:67-108. [DOI: 10.1016/bs.ircmb.2020.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
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38
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Caridi CP, Plessner M, Grosse R, Chiolo I. Nuclear actin filaments in DNA repair dynamics. Nat Cell Biol 2019; 21:1068-1077. [PMID: 31481797 PMCID: PMC6736642 DOI: 10.1038/s41556-019-0379-1] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 07/24/2019] [Indexed: 02/06/2023]
Abstract
Recent development of innovative tools for live imaging of actin filaments (F-actin) enabled the detection of surprising nuclear structures responding to various stimuli, challenging previous models that actin is substantially monomeric in the nucleus. We review these discoveries, focusing on double-strand break (DSB) repair responses. These studies revealed a remarkable network of nuclear filaments and regulatory mechanisms coordinating chromatin dynamics with repair progression and led to a paradigm shift by uncovering the directed movement of repair sites.
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Affiliation(s)
| | - Matthias Plessner
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg im Breisgau, Germany
- CIBSS - Centre for Integrative Biological Signaling Studies, University of Freiburg, Freiburg im Breisgau, Germany
| | - Robert Grosse
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg im Breisgau, Germany
- CIBSS - Centre for Integrative Biological Signaling Studies, University of Freiburg, Freiburg im Breisgau, Germany
| | - Irene Chiolo
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, USA.
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