1
|
Zhang D, Li L, Li M, Cao X. Biological functions and clinic significance of SAF‑A (Review). Biomed Rep 2024; 20:88. [PMID: 38665420 PMCID: PMC11040223 DOI: 10.3892/br.2024.1776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
As one member of the heterogeneous ribonucleoprotein (hnRNP) family, scaffold attachment factor A (SAF-A) or hnRNP U, is an abundant nuclear protein. With RNA and DNA binding activities, SAF-A has multiple functions. The present review focused on the biological structure and different roles of SAF-A and SAF-A-related diseases. It was found that SAF-A maintains the higher-order chromatin organization via RNA and DNA, and regulates transcription at the initiation and elongation stages. In addition to regulating pre-mRNA splicing, mRNA transportation and stabilization, SAF-A participates in double-strand breaks and mitosis repair. Therefore, the aberrant expression and mutation of SAF-A results in tumors and impaired neurodevelopment. Moreover, SAF-A may play a role in the anti-virus system. In conclusion, due to its essential biological functions, SAF-A may be a valuable clinical prediction factor or therapeutic target. Since the role of SAF-A in tumors and viral infections may be controversial, more animal experiments and clinical assays are needed.
Collapse
Affiliation(s)
- Daiquan Zhang
- Department of Traditional Chinese Medicine, West China Second University Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Li Li
- Immune Mechanism and Therapy of Major Diseases of Luzhou Key Laboratory, School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan 646000, P.R. China
| | - Mengni Li
- Department of Pediatrics, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072, P.R. China
| | - Xinmei Cao
- Immune Mechanism and Therapy of Major Diseases of Luzhou Key Laboratory, School of Basic Medical Sciences, Southwest Medical University, Luzhou, Sichuan 646000, P.R. China
| |
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
Kyheröinen S, Prajapati B, Sokolova M, Schmitz M, Viita T, Geyer M, Vartiainen MK. Actin associates with actively elongating genes and binds directly to the Cdk9 subunit of P-TEFb. J Biol Chem 2024; 300:105698. [PMID: 38301887 PMCID: PMC10891344 DOI: 10.1016/j.jbc.2024.105698] [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: 11/15/2023] [Revised: 01/08/2024] [Accepted: 01/21/2024] [Indexed: 02/03/2024] Open
Abstract
Nuclear actin has been demonstrated to be essential for optimal transcription, but the molecular mechanisms and direct binding partner for actin in the RNA polymerase complex have remained unknown. By using purified proteins in a variety of biochemical assays, we demonstrate a direct and specific interaction between monomeric actin and Cdk9, the kinase subunit of the positive transcription elongation factor b required for RNA polymerase II pause-release. This interaction efficiently prevents actin polymerization, is not dependent on kinase activity of Cdk9, and is not involved with releasing positive transcription elongation factor b from its inhibitor 7SK snRNP complex. Supporting the specific role for actin in the elongation phase of transcription, chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) reveals that actin interacts with genes only upon their active transcription elongation. This study therefore provides novel insights into the mechanisms by which actin facilitates the transcription process.
Collapse
Affiliation(s)
- Salla Kyheröinen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Bina Prajapati
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Maria Sokolova
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | | | - Tiina Viita
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Matthias Geyer
- Institute of Structural Biology, University of Bonn, Bonn, Germany
| | - Maria K Vartiainen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.
| |
Collapse
|
4
|
Venit T, Sapkota O, Abdrabou WS, Loganathan P, Pasricha R, Mahmood SR, El Said NH, Sherif S, Thomas S, Abdelrazig S, Amin S, Bedognetti D, Idaghdour Y, Magzoub M, Percipalle P. Positive regulation of oxidative phosphorylation by nuclear myosin 1 protects cells from metabolic reprogramming and tumorigenesis in mice. Nat Commun 2023; 14:6328. [PMID: 37816864 PMCID: PMC10564744 DOI: 10.1038/s41467-023-42093-w] [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: 08/04/2022] [Accepted: 09/29/2023] [Indexed: 10/12/2023] Open
Abstract
Metabolic reprogramming is one of the hallmarks of tumorigenesis. Here, we show that nuclear myosin 1 (NM1) serves as a key regulator of cellular metabolism. NM1 directly affects mitochondrial oxidative phosphorylation (OXPHOS) by regulating mitochondrial transcription factors TFAM and PGC1α, and its deletion leads to underdeveloped mitochondria inner cristae and mitochondrial redistribution within the cell. These changes are associated with reduced OXPHOS gene expression, decreased mitochondrial DNA copy number, and deregulated mitochondrial dynamics, which lead to metabolic reprogramming of NM1 KO cells from OXPHOS to aerobic glycolysis.This, in turn, is associated with a metabolomic profile typical for cancer cells, namely increased amino acid-, fatty acid-, and sugar metabolism, and increased glucose uptake, lactate production, and intracellular acidity. NM1 KO cells form solid tumors in a mouse model, suggesting that the metabolic switch towards aerobic glycolysis provides a sufficient carcinogenic signal. We suggest that NM1 plays a role as a tumor suppressor and that NM1 depletion may contribute to the Warburg effect at the onset of tumorigenesis.
Collapse
Affiliation(s)
- Tomas Venit
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Oscar Sapkota
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Wael Said Abdrabou
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
- Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Palanikumar Loganathan
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Renu Pasricha
- Core Technology Platforms, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Syed Raza Mahmood
- Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Nadine Hosny El Said
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Shimaa Sherif
- Translational Medicine Department, Research Branch, Sidra Medicine, Doha, Qatar
| | - Sneha Thomas
- Core Technology Platforms, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Salah Abdelrazig
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Shady Amin
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Davide Bedognetti
- Translational Medicine Department, Research Branch, Sidra Medicine, Doha, Qatar
- Department of Internal Medicine and Medical Specialties (DiMI), University of Genoa, Genoa, Italy
- College of Health and Life Sciences, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Youssef Idaghdour
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
- Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Mazin Magzoub
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates
| | - Piergiorgio Percipalle
- Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates.
- Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box, 129188, Abu Dhabi, United Arab Emirates.
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91, Stockholm, Sweden.
| |
Collapse
|
5
|
Dugger SA, Dhindsa RS, Sampaio GDA, Ressler AK, Rafikian EE, Petri S, Letts VA, Teoh J, Ye J, Colombo S, Peng Y, Yang M, Boland MJ, Frankel WN, Goldstein DB. Neurodevelopmental deficits and cell-type-specific transcriptomic perturbations in a mouse model of HNRNPU haploinsufficiency. PLoS Genet 2023; 19:e1010952. [PMID: 37782669 PMCID: PMC10569524 DOI: 10.1371/journal.pgen.1010952] [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] [Received: 03/29/2023] [Revised: 10/12/2023] [Accepted: 09/01/2023] [Indexed: 10/04/2023] Open
Abstract
Heterozygous de novo loss-of-function mutations in the gene expression regulator HNRNPU cause an early-onset developmental and epileptic encephalopathy. To gain insight into pathological mechanisms and lay the potential groundwork for developing targeted therapies, we characterized the neurophysiologic and cell-type-specific transcriptomic consequences of a mouse model of HNRNPU haploinsufficiency. Heterozygous mutants demonstrated global developmental delay, impaired ultrasonic vocalizations, cognitive dysfunction and increased seizure susceptibility, thus modeling aspects of the human disease. Single-cell RNA-sequencing of hippocampal and neocortical cells revealed widespread, yet modest, dysregulation of gene expression across mutant neuronal subtypes. We observed an increased burden of differentially-expressed genes in mutant excitatory neurons of the subiculum-a region of the hippocampus implicated in temporal lobe epilepsy. Evaluation of transcriptomic signature reversal as a therapeutic strategy highlights the potential importance of generating cell-type-specific signatures. Overall, this work provides insight into HNRNPU-mediated disease mechanisms and provides a framework for using single-cell RNA-sequencing to study transcriptional regulators implicated in disease.
Collapse
Affiliation(s)
- Sarah A. Dugger
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Ryan S. Dhindsa
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute of Texas Children’s Hospital, Houston, Texas, United States of America
| | - Gabriela De Almeida Sampaio
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Andrew K. Ressler
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Elizabeth E. Rafikian
- Mouse Neurobehavioral Core Facility, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Sabrina Petri
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Verity A. Letts
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
| | - JiaJie Teoh
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Junqiang Ye
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, New York, United States of America
- Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, New York, United States of America
| | - Sophie Colombo
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Yueqing Peng
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Mu Yang
- Mouse Neurobehavioral Core Facility, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Michael J. Boland
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Neurology, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Wayne N. Frankel
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York, United States of America
| | - David B. Goldstein
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York, United States of America
| |
Collapse
|
6
|
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: 1] [Impact Index Per Article: 1.0] [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.
Collapse
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.
| |
Collapse
|
7
|
Balaban C, Sztacho M, Antiga L, Miladinović A, Harata M, Hozák P. PIP2-Effector Protein MPRIP Regulates RNA Polymerase II Condensation and Transcription. Biomolecules 2023; 13:biom13030426. [PMID: 36979361 PMCID: PMC10046169 DOI: 10.3390/biom13030426] [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: 01/23/2023] [Revised: 02/17/2023] [Accepted: 02/21/2023] [Indexed: 03/02/2023] Open
Abstract
The specific post-translational modifications of the C-terminal domain (CTD) of the Rpb1 subunit of RNA polymerase II (RNAPII) correlate with different stages of transcription. The phosphorylation of the Ser5 residues of this domain associates with the initiation condensates, which are formed through liquid-liquid phase separation (LLPS). The subsequent Tyr1 phosphorylation of the CTD peaks at the promoter-proximal region and is involved in the pause-release of RNAPII. By implementing super-resolution microscopy techniques, we previously reported that the nuclear Phosphatidylinositol 4,5-bisphosphate (PIP2) associates with the Ser5-phosphorylated-RNAPII complex and facilitates the RNAPII transcription. In this study, we identified Myosin Phosphatase Rho-Interacting Protein (MPRIP) as a novel regulator of the RNAPII transcription that recruits Tyr1-phosphorylated CTD (Tyr1P-CTD) to nuclear PIP2-containing structures. The depletion of MPRIP increases the number of the initiation condensates, indicating a defect in the transcription. We hypothesize that MPRIP regulates the condensation and transcription through affecting the association of the RNAPII complex with nuclear PIP2-rich structures. The identification of Tyr1P-CTD as an interactor of PIP2 and MPRIP further points to a regulatory role in RNAPII pause-release, where the susceptibility of the transcriptional complex to leave the initiation condensate depends on its association with nuclear PIP2-rich structures. Moreover, the N-terminal domain of MPRIP, which is responsible for the interaction with the Tyr1P-CTD, contains an F-actin binding region that offers an explanation of how nuclear F-actin formations can affect the RNAPII transcription and condensation. Overall, our findings shed light on the role of PIP2 in RNAPII transcription through identifying the F-actin binding protein MPRIP as a transcription regulator and a determinant of the condensation of RNAPII.
Collapse
Affiliation(s)
- Can Balaban
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Martin Sztacho
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, 142 20 Prague, Czech Republic
- Correspondence: (M.S.); (P.H.)
| | - Ludovica Antiga
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Ana Miladinović
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Masahiko Harata
- Laboratory of Molecular Biochemistry, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 468-1, Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Pavel Hozák
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, 142 20 Prague, Czech Republic
- Correspondence: (M.S.); (P.H.)
| |
Collapse
|
8
|
Talbot DE, Vormezeele BJ, Kimble GC, Wineland DM, Kelpsch DJ, Giedt MS, Tootle TL. Prostaglandins limit nuclear actin to control nucleolar function during oogenesis. Front Cell Dev Biol 2023; 11:1072456. [PMID: 36875757 PMCID: PMC9981675 DOI: 10.3389/fcell.2023.1072456] [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: 10/17/2022] [Accepted: 02/06/2023] [Indexed: 02/19/2023] Open
Abstract
Prostaglandins (PGs), locally acting lipid signals, regulate female reproduction, including oocyte development. However, the cellular mechanisms of PG action remain largely unknown. One cellular target of PG signaling is the nucleolus. Indeed, across organisms, loss of PGs results in misshapen nucleoli, and changes in nucleolar morphology are indicative of altered nucleolar function. A key role of the nucleolus is to transcribe ribosomal RNA (rRNA) to drive ribosomal biogenesis. Here we take advantage of the robust, in vivo system of Drosophila oogenesis to define the roles and downstream mechanisms whereby PGs regulate the nucleolus. We find that the altered nucleolar morphology due to PG loss is not due to reduced rRNA transcription. Instead, loss of PGs results in increased rRNA transcription and overall protein translation. PGs modulate these nucleolar functions by tightly regulating nuclear actin, which is enriched in the nucleolus. Specifically, we find that loss of PGs results in both increased nucleolar actin and changes in its form. Increasing nuclear actin, by either genetic loss of PG signaling or overexpression of nuclear targeted actin (NLS-actin), results in a round nucleolar morphology. Further, loss of PGs, overexpression of NLS-actin or loss of Exportin 6, all manipulations that increase nuclear actin levels, results in increased RNAPI-dependent transcription. Together these data reveal PGs carefully balance the level and forms of nuclear actin to control the level of nucleolar activity required for producing fertilization competent oocytes.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Tina L. Tootle
- Anatomy and Cell Biology, University of Iowa Carver College of Medicine, Iowa City, IA, United States
| |
Collapse
|
9
|
Mahmood SR, Said NHE, Gunsalus KC, Percipalle P. β-actin mediated H3K27ac changes demonstrate the link between compartment switching and enhancer-dependent transcriptional regulation. Genome Biol 2023; 24:18. [PMID: 36698204 PMCID: PMC9875490 DOI: 10.1186/s13059-023-02853-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 01/09/2023] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Recent work has demonstrated that three-dimensional genome organization is directly affected by changes in the levels of nuclear cytoskeletal proteins such as β-actin. The mechanisms which translate changes in 3D genome structure into changes in transcription, however, are not fully understood. Here, we use a comprehensive genomic analysis of cells lacking nuclear β-actin to investigate the mechanistic links between compartment organization, enhancer activity, and gene expression. RESULTS Using HiC-Seq, ATAC-Seq, and RNA-Seq, we first demonstrate that transcriptional and chromatin accessibility changes observed upon β-actin loss are highly enriched in compartment-switching regions. Accessibility changes within compartment switching genes, however, are mainly observed in non-promoter regions which potentially represent distal regulatory elements. Our results also show that β-actin loss induces widespread accumulation of the enhancer-specific epigenetic mark H3K27ac. Using the ABC model of enhancer annotation, we then establish that these epigenetic changes have a direct impact on enhancer activity and underlie transcriptional changes observed upon compartment switching. A complementary analysis of fibroblasts undergoing reprogramming into pluripotent stem cells further confirms that this relationship between compartment switching and enhancer-dependent transcriptional change is not specific to β-actin knockout cells but represents a general mechanism linking compartment-level genome organization to gene expression. CONCLUSIONS We demonstrate that enhancer-dependent transcriptional regulation plays a crucial role in driving gene expression changes observed upon compartment-switching. Our results also reveal a novel function of nuclear β-actin in regulating enhancer function by influencing H3K27 acetylation levels.
Collapse
Affiliation(s)
- Syed Raza Mahmood
- grid.440573.10000 0004 1755 5934Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box 129188, Abu Dhabi, United Arab Emirates ,grid.137628.90000 0004 1936 8753Department of Biology, New York University, New York, NY 10003 USA
| | - Nadine Hosny El Said
- grid.440573.10000 0004 1755 5934Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box 129188, Abu Dhabi, United Arab Emirates
| | - Kristin C. Gunsalus
- grid.440573.10000 0004 1755 5934Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box 129188, Abu Dhabi, United Arab Emirates ,grid.137628.90000 0004 1936 8753Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY 10003 USA
| | - Piergiorgio Percipalle
- grid.440573.10000 0004 1755 5934Center for Genomics and Systems Biology, New York University Abu Dhabi (NYUAD), P.O. Box 129188, Abu Dhabi, United Arab Emirates ,grid.440573.10000 0004 1755 5934Program in Biology, Division of Science and Mathematics, New York University Abu Dhabi (NYUAD), P.O. Box 129188, Abu Dhabi, United Arab Emirates ,grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91 Stockholm, Sweden
| |
Collapse
|
10
|
Wang H, Liu H, Zhao X, Chen X. Heterogeneous nuclear ribonucleoprotein U-actin complex derived from extracellular vesicles facilitates proliferation and migration of human coronary artery endothelial cells by promoting RNA polymerase II transcription. Bioengineered 2022; 13:11469-11486. [PMID: 35535400 PMCID: PMC9276035 DOI: 10.1080/21655979.2022.2066754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Coronary artery disease (CAD) represents a fatal public threat. The involvement of extracellular vesicles (EVs) in CAD has been documented. This study explored the regulation of embryonic stem cells (ESCs)-derived EVs-hnRNPU-actin complex in human coronary artery endothelial cell (HCAEC) growth. Firstly, in vitro HCAEC hypoxia models were established. EVs were extracted from ESCs by ultracentrifugation. HCAECs were treated with EVs and si-VEGF for 24 h under hypoxia, followed by assessment of cell proliferation, apoptosis, migration, and tube formation. Uptake of EVs by HCAECs was testified. Additionally, hnRNPU, VEGF, and RNA Pol II levels were determined using Western blotting and CHIP assays. Interaction between hnRNPU and actin was evaluated by Co-immunoprecipitation assay. HCAEC viability and proliferation were lowered, apoptosis was enhanced, wound fusion was decreased, and the number of tubular capillary structures was reduced under hypoxia, whereas ESC-EVs treatment counteracted these effects. Moreover, EVs transferred hnRNPU into HCAECs. EVs-hnRNPU-actin complex increased RNA Pol II level on the VEGF gene promoter and promoted VEGF expression in HCAECs. Inhibition of hnRNPU or VEGF both annulled the promotion of EVs on HCAEC growth. Collectively, ESC-EVs-hnRNPU-actin increased RNA Pol II phosphorylation and VEGF expression, thus promoting HCAEC growth.
Collapse
Affiliation(s)
- Han Wang
- Department of Cardiovascular, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Hengdao Liu
- Department of Cardiovascular, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Xi Zhao
- Department of Cardiovascular, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Xiaowei Chen
- Department of Cardiovascular, First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| |
Collapse
|
11
|
Abstract
Actin is a highly conserved protein in mammals. The actin dynamics is regulated by actin-binding proteins and actin-related proteins. Nuclear actin and these regulatory proteins participate in multiple nuclear processes, including chromosome architecture organization, chromatin remodeling, transcription machinery regulation, and DNA repair. It is well known that the dysfunctions of these processes contribute to the development of cancer. Moreover, emerging evidence has shown that the deregulated actin dynamics is also related to cancer. This chapter discusses how the deregulation of nuclear actin dynamics contributes to tumorigenesis via such various nuclear events.
Collapse
Affiliation(s)
- Yuanjian Huang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Shengzhe Zhang
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jae-Il Park
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center and Health Science Center, Houston, TX, USA.
- Program in Genetics and Epigenetics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| |
Collapse
|
12
|
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.
Collapse
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.
| |
Collapse
|
13
|
Liang Y, Fan Y, Liu Y, Fan H. HNRNPU promotes the progression of hepatocellular carcinoma by enhancing CDK2 transcription. Exp Cell Res 2021; 409:112898. [PMID: 34737140 DOI: 10.1016/j.yexcr.2021.112898] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/29/2021] [Accepted: 10/25/2021] [Indexed: 02/08/2023]
Abstract
The nuclear matrix-associated protein Heterogeneous Nuclear Ribonucleoprotein U (HNRNPU), also known as SAF-A, is known to maintain active chromatin structure in mouse hepatocytes. However, the functional roles and molecular mechanisms of HNRNPU in the development of hepatocellular carcinoma (HCC) remain largely unknown. Herein, we found that HNRNPU was upregulated in HCC, and the proliferation of HCC cells was inhibited in vitro and in vivo upon HNRNPU knockdown. Moreover, the upregulation of HNRNPU was correlated with poor prognosis in HCC. Mechanistically, HNRNPU bound to the CDK2 gene locus, a key factor in cell cycle regulation, where it was enriched with H3K27 acetylation (H3K27ac), H3K9 acetylation (H3K9ac), and H3K4 mono-methylation (H3K4me1). Furthermore, HNRNPU knockdown reduced the levels of H3K27ac and H3K9ac at the binding site, where the levels of H3K27 tri-methylation (H3K27me3) were increased, eventually leading to the downregulation of CDK2. Collectively, our results provide a new mechanism whereby HNRNPU promotes HCC development by enhancing the transcription of CDK2.
Collapse
Affiliation(s)
- Yi Liang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated By the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Yao Fan
- Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, 646000, China
| | - Yu Liu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated By the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China
| | - Hui Fan
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated By the Chinese Ministry of Education, Chongqing Medical University, Chongqing, China.
| |
Collapse
|
14
|
Kumar A, Zhong Y, Albrecht A, Sang PB, Maples A, Liu Z, Vinayachandran V, Reja R, Lee CF, Kumar A, Chen J, Xiao J, Park B, Shen J, Liu B, Person MD, Trybus KM, Zhang KYJ, Pugh BF, Kamm KE, Milewicz DM, Shen X, Kapoor P. Actin R256 Mono-methylation Is a Conserved Post-translational Modification Involved in Transcription. Cell Rep 2021; 32:108172. [PMID: 32997990 PMCID: PMC8860185 DOI: 10.1016/j.celrep.2020.108172] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 07/11/2020] [Accepted: 08/27/2020] [Indexed: 12/19/2022] Open
Abstract
Nuclear actin has been elusive due to the lack of knowledge about molecular mechanisms. From actin-containing chromatin remodeling complexes, we discovered an arginine mono-methylation mark on an evolutionarily conserved R256 residue of actin (R256me1). Actin R256 mutations in yeast affect nuclear functions and cause diseases in human. Interestingly, we show that an antibody specific for actin R256me1 preferentially stains nuclear actin over cytoplasmic actin in yeast, mouse, and human cells. We also show that actin R256me1 is regulated by protein arginine methyl transferase-5 (PRMT5) in HEK293 cells. A genome-wide survey of actin R256me1 mark provides a landscape for nuclear actin correlated with transcription. Further, gene expression and protein interaction studies uncover extensive correlations between actin R256me1 and active transcription. The discovery of actin R256me1 mark suggests a fundamental mechanism to distinguish nuclear actin from cytoplasmic actin through post-translational modification (PTM) and potentially implicates an actin PTM mark in transcription and human diseases. Nuclear actin and actin PTMs are poorly understood. Kumar et al. discover a system of actin PTMs similar to histone PTMs, including a conserved mark on nuclear actin (R256me1) with potential implications for transcription and human diseases.
Collapse
Affiliation(s)
- Ashok Kumar
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
| | - Yuan Zhong
- Department of Epigenetics and Molecular Carcinogenesis, Science Park Research Division, The University of Texas M.D. Anderson Cancer Center, Smithville, TX 78957, USA
| | - Amelie Albrecht
- Department of Epigenetics and Molecular Carcinogenesis, Science Park Research Division, The University of Texas M.D. Anderson Cancer Center, Smithville, TX 78957, USA; The University of Texas M.D. Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
| | - Pau Biak Sang
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
| | - Adrian Maples
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
| | - Zhenan Liu
- Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Vinesh Vinayachandran
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Rohit Reja
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Chia-Fang Lee
- ICMB Proteomics Facility, The University of Texas at Austin, Austin, TX 78712, USA
| | - Ashutosh Kumar
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - Jiyuan Chen
- Department of Internal Medicine, University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Jing Xiao
- Department of Epigenetics and Molecular Carcinogenesis, Science Park Research Division, The University of Texas M.D. Anderson Cancer Center, Smithville, TX 78957, USA
| | - Bongsoo Park
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jianjun Shen
- Department of Epigenetics and Molecular Carcinogenesis, Science Park Research Division, The University of Texas M.D. Anderson Cancer Center, Smithville, TX 78957, USA
| | - Bin Liu
- Department of Epigenetics and Molecular Carcinogenesis, Science Park Research Division, The University of Texas M.D. Anderson Cancer Center, Smithville, TX 78957, USA
| | - Maria D Person
- ICMB Proteomics Facility, The University of Texas at Austin, Austin, TX 78712, USA
| | - Kathleen M Trybus
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405, USA
| | - Kam Y J Zhang
- Laboratory for Structural Bioinformatics, Center for Biosystems Dynamics Research, RIKEN, 1-7-22 Suehiro, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
| | - B Franklin Pugh
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Kristine E Kamm
- Department of Physiology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Dianna M Milewicz
- Department of Internal Medicine, University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Xuetong Shen
- Department of Epigenetics and Molecular Carcinogenesis, Science Park Research Division, The University of Texas M.D. Anderson Cancer Center, Smithville, TX 78957, USA.
| | - Prabodh Kapoor
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA.
| |
Collapse
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
Transcription/Replication Conflicts in Tumorigenesis and Their Potential Role as Novel Therapeutic Targets in Multiple Myeloma. Cancers (Basel) 2021; 13:cancers13153755. [PMID: 34359660 PMCID: PMC8345052 DOI: 10.3390/cancers13153755] [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] [Received: 05/12/2021] [Revised: 07/13/2021] [Accepted: 07/22/2021] [Indexed: 12/24/2022] Open
Abstract
Simple Summary Multiple myeloma is a hematologic cancer characterized by the accumulation of malignant plasma cells in the bone marrow. It remains a mostly incurable disease due to the inability to overcome refractory disease and drug-resistant relapse. Oncogenic transformation of PC in multiple myeloma is thought to occur within the secondary lymphoid organs. However, the precise molecular events leading to myelomagenesis remain obscure. Here, we identified genes involved in the prevention and the resolution of conflicts between the replication and transcription significantly overexpressed during the plasma cell differentiation process and in multiple myeloma cells. We discussed the potential role of these factors in myelomagenesis and myeloma biology. The specific targeting of these factors might constitute a new therapeutic strategy in multiple myeloma. Abstract Plasma cells (PCs) have an essential role in humoral immune response by secretion of antibodies, and represent the final stage of B lymphocytes differentiation. During this differentiation, the pre-plasmablastic stage is characterized by highly proliferative cells that start to secrete immunoglobulins (Igs). Thus, replication and transcription must be tightly regulated in these cells to avoid transcription/replication conflicts (TRCs), which could increase replication stress and lead to genomic instability. In this review, we analyzed expression of genes involved in TRCs resolution during B to PC differentiation and identified 41 genes significantly overexpressed in the pre-plasmablastic stage. This illustrates the importance of mechanisms required for adequate processing of TRCs during PCs differentiation. Furthermore, we identified that several of these factors were also found overexpressed in purified PCs from patients with multiple myeloma (MM) compared to normal PCs. Malignant PCs produce high levels of Igs concomitantly with cell cycle deregulation. Therefore, increasing the TRCs occurring in MM cells could represent a potent therapeutic strategy for MM patients. Here, we describe the potential roles of TRCs resolution factors in myelomagenesis and discuss the therapeutic interest of targeting the TRCs resolution machinery in MM.
Collapse
|
17
|
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: 10] [Impact Index Per Article: 3.3] [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.
Collapse
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
| |
Collapse
|
18
|
Wagh K, Ishikawa M, Garcia DA, Stavreva DA, Upadhyaya A, Hager GL. Mechanical Regulation of Transcription: Recent Advances. Trends Cell Biol 2021; 31:457-472. [PMID: 33712293 PMCID: PMC8221528 DOI: 10.1016/j.tcb.2021.02.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 01/01/2023]
Abstract
Mechanotransduction is the ability of a cell to sense mechanical cues from its microenvironment and convert them into biochemical signals to elicit adaptive transcriptional and other cellular responses. Here, we describe recent advances in the field of mechanical regulation of transcription, highlight mechanical regulation of the epigenome as a key novel aspect of mechanotransduction, and describe recent technological advances that could further elucidate the link between mechanical stimuli and gene expression. In this review, we emphasize the importance of mechanotransduction as one of the governing principles of cancer progression, underscoring the need to conduct further studies of the molecular mechanisms involved in sensing mechanical cues and coordinating transcriptional responses.
Collapse
Affiliation(s)
- Kaustubh Wagh
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; Department of Physics, University of Maryland, College Park, MD 20742, USA
| | - Momoko Ishikawa
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - David A Garcia
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA; Department of Physics, University of Maryland, College Park, MD 20742, USA
| | - Diana A Stavreva
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Arpita Upadhyaya
- Department of Physics, University of Maryland, College Park, MD 20742, USA; Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742, USA.
| | - Gordon L Hager
- Laboratory of Receptor Biology and Gene Expression, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
19
|
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.
Collapse
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
| |
Collapse
|
20
|
Michel JB. Phylogenic Determinants of Cardiovascular Frailty, Focus on Hemodynamics and Arterial Smooth Muscle Cells. Physiol Rev 2020; 100:1779-1837. [DOI: 10.1152/physrev.00022.2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The evolution of the circulatory system from invertebrates to mammals has involved the passage from an open system to a closed in-parallel system via a closed in-series system, accompanying the increasing complexity and efficiency of life’s biological functions. The archaic heart enables pulsatile motion waves of hemolymph in invertebrates, and the in-series circulation in fish occurs with only an endothelium, whereas mural smooth muscle cells appear later. The present review focuses on evolution of the circulatory system. In particular, we address how and why this evolution took place from a closed, flowing, longitudinal conductance at low pressure to a flowing, highly pressurized and bifurcating arterial compartment. However, although arterial pressure was the latest acquired hemodynamic variable, the general teleonomy of the evolution of species is the differentiation of individual organ function, supported by specific fueling allowing and favoring partial metabolic autonomy. This was achieved via the establishment of an active contractile tone in resistance arteries, which permitted the regulation of blood supply to specific organ activities via its localized function-dependent inhibition (active vasodilation). The global resistance to viscous blood flow is the peripheral increase in frictional forces caused by the tonic change in arterial and arteriolar radius, which backscatter as systemic arterial blood pressure. Consequently, the arterial pressure gradient from circulating blood to the adventitial interstitium generates the unidirectional outward radial advective conductance of plasma solutes across the wall of conductance arteries. This hemodynamic evolution was accompanied by important changes in arterial wall structure, supported by smooth muscle cell functional plasticity, including contractility, matrix synthesis and proliferation, endocytosis and phagocytosis, etc. These adaptive phenotypic shifts are due to epigenetic regulation, mainly related to mechanotransduction. These paradigms actively participate in cardio-arterial pathologies such as atheroma, valve disease, heart failure, aneurysms, hypertension, and physiological aging.
Collapse
|
21
|
Taylor K, Sobczak K. Intrinsic Regulatory Role of RNA Structural Arrangement in Alternative Splicing Control. Int J Mol Sci 2020; 21:ijms21145161. [PMID: 32708277 PMCID: PMC7404189 DOI: 10.3390/ijms21145161] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 07/17/2020] [Indexed: 12/14/2022] Open
Abstract
Alternative splicing is a highly sophisticated process, playing a significant role in posttranscriptional gene expression and underlying the diversity and complexity of organisms. Its regulation is multilayered, including an intrinsic role of RNA structural arrangement which undergoes time- and tissue-specific alterations. In this review, we describe the principles of RNA structural arrangement and briefly decipher its cis- and trans-acting cellular modulators which serve as crucial determinants of biological functionality of the RNA structure. Subsequently, we engage in a discussion about the RNA structure-mediated mechanisms of alternative splicing regulation. On one hand, the impairment of formation of optimal RNA structures may have critical consequences for the splicing outcome and further contribute to understanding the pathomechanism of severe disorders. On the other hand, the structural aspects of RNA became significant features taken into consideration in the endeavor of finding potential therapeutic treatments. Both aspects have been addressed by us emphasizing the importance of ongoing studies in both fields.
Collapse
|
22
|
Abstract
The presence of actin in the nucleus has historically been a highly contentious issue. It is now, however, well accepted that actin has physiologically important roles in the nucleus. In this Review, we describe the evolution of our thinking about actin in the nucleus starting with evidence supporting its involvement in transcription, chromatin remodeling and intranuclear movements. We also review the growing literature on the mechanisms that regulate the import and export of actin and how post-translational modifications of actin could regulate nuclear actin. We end with an extended discussion of the role of nuclear actin in the repair of DNA double stranded breaks.
Collapse
Affiliation(s)
- Leonid Serebryannyy
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, United States
| | - Primal de Lanerolle
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, United States.
| |
Collapse
|
23
|
Sommerova L, Ondrouskova E, Martisova A, Zoumpourlis V, Galtsidis S, Hrstka R. ZEB1/miR-200c/AGR2: A New Regulatory Loop Modulating the Epithelial-Mesenchymal Transition in Lung Adenocarcinomas. Cancers (Basel) 2020; 12:cancers12061614. [PMID: 32570918 PMCID: PMC7352583 DOI: 10.3390/cancers12061614] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/12/2020] [Accepted: 06/13/2020] [Indexed: 12/12/2022] Open
Abstract
Epithelial-mesenchymal transition (EMT) is a process involved not only in morphogenesis and embryonic development, but also in cancer progression, whereby tumor cells obtain a more aggressive metastatic phenotype. Anterior gradient protein 2 (AGR2) maintains the epithelial phenotype and blocks the induction of EMT, thus playing an undeniable role in tumor progression. However, the mechanism through which AGR2 expression is regulated, not only during EMT, but also in the early stages of cancer development, remains to be elucidated. In the present study, we show an inverse correlation of AGR2 with ZEB1 (zinc finger enhancer binding protein, δEF1) that was verified by analysis of several independent clinical data sets of lung adenocarcinomas. We also identified the ZEB1 binding site within the AGR2 promoter region and confirmed AGR2 as a novel molecular target of ZEB1. The overexpression of ZEB1 decreased the promoter activity of the AGR2 gene, which resulted in reduced AGR2 protein level and the acquisition of a more invasive phenotype of these lung cancer cells. Conversely, silencing of ZEB1 led not only to increased levels of AGR2 protein, but also attenuated the invasiveness of tumor cells. The AGR2 knockout, vice versa, increased ZEB1 expression, indicating that the ZEB1/AGR2 regulatory axis may function in a double negative feedback loop. In conclusion, we revealed for the first time that ZEB1 regulates AGR2 at the transcriptional level, while AGR2 presence contributes to ZEB1 mRNA degradation. Thus, our data identify a new regulatory mechanism between AGR2 and ZEB1, two rivals in the EMT process, tightly associated with the development of metastasis.
Collapse
Affiliation(s)
- Lucia Sommerova
- Research Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic; (L.S.); (E.O.); (A.M.)
| | - Eva Ondrouskova
- Research Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic; (L.S.); (E.O.); (A.M.)
| | - Andrea Martisova
- Research Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic; (L.S.); (E.O.); (A.M.)
| | - Vassilis Zoumpourlis
- Biomedical Applications Unit, Institute of Biology, Medicinal Chemistry & Biotechnology, NHRF 48 Vassileos Constantinou Ave., 11635 Athens, Greece;
| | - Sotirios Galtsidis
- Life Sciences Research Unit, University of Luxembourg, Campus Belval, Biotech 1, Avenue des Hauts Fourneaux, L-4362 Esch-sur-Alzette, Luxembourg;
| | - Roman Hrstka
- Research Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic; (L.S.); (E.O.); (A.M.)
- Correspondence: ; Tel.: +420-543-133-306
| |
Collapse
|
24
|
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]
|
25
|
Galigniana NM, Charó NL, Uranga R, Cabanillas AM, Piwien-Pilipuk G. Oxidative stress induces transcription of telomeric repeat-containing RNA (TERRA) by engaging PKA signaling and cytoskeleton dynamics. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118643. [DOI: 10.1016/j.bbamcr.2020.118643] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 12/27/2019] [Accepted: 01/02/2020] [Indexed: 12/11/2022]
|
26
|
Wei M, Fan X, Ding M, Li R, Shao S, Hou Y, Meng S, Tang F, Li C, Sun Y. Nuclear actin regulates inducible transcription by enhancing RNA polymerase II clustering. SCIENCE ADVANCES 2020; 6:eaay6515. [PMID: 32494599 PMCID: PMC7159918 DOI: 10.1126/sciadv.aay6515] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 01/22/2020] [Indexed: 05/22/2023]
Abstract
Gene expression in response to stimuli underlies many fundamental processes. However, how transcription is regulated under these scenarios is largely unknown. Here, we find a previously unknown role of nuclear actin in transcriptional regulation. The RNA-seq data reveal that nuclear actin is required for the serum-induced transcriptional program. Using super-resolution imaging, we found a remarkable enhancement of RNA polymerase II (Pol II) clustering upon serum stimulation, and this enhancement requires nuclear actin. Pol II clusters colocalized with the serum-response genes and nuclear actin filaments upon serum stimulation. Furthermore, N-WASP is required for serum-enhanced Pol II clustering. N-WASP phase-separated with Pol II and nuclear actin. In addition to serum stimulation, nuclear actin also enhanced Pol II clustering upon interferon-γ treatment. Together, our work unveils that nuclear actin promotes the formation of transcription factory on inducible genes, acting as a general mechanism underlying the rapid response to environmental cues.
Collapse
Affiliation(s)
- Mian Wei
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Xiaoying Fan
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Miao Ding
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Ruifeng Li
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China
| | - Shipeng Shao
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Yingping Hou
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Shaoshuai Meng
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
| | - Fuchou Tang
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China
| | - Cheng Li
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, China
- Center for Statistical Science, Center for Bioinformatics, Peking University, Beijing 100871, China
| | - Yujie Sun
- State Key Laboratory of Membrane Biology, Biomedical Pioneer Innovation Center (BIOPIC), School of Life Sciences, Peking University, Beijing 100871, China
- Corresponding author.
| |
Collapse
|
27
|
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: 41] [Impact Index Per Article: 10.3] [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.
Collapse
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
| |
Collapse
|
28
|
|
29
|
Wang J, Wu Y, Zhang X, Zhang F, Lü D, Shangguan B, Gao Y, Long M. Flow-enhanced priming of hESCs through H2B acetylation and chromatin decondensation. Stem Cell Res Ther 2019; 10:349. [PMID: 31775893 PMCID: PMC6880446 DOI: 10.1186/s13287-019-1454-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/21/2019] [Accepted: 10/15/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Distinct mechanical stimuli are known to manipulate the behaviors of embryonic stem cells (ESCs). Fundamental rationale of how ESCs respond to mechanical forces and the potential biological effects remain elusive. Here we conducted the mechanobiological study for hESCs upon mechanomics analysis to unravel typical mechanosensitive processes on hESC-specific fluid shear. METHODS hESC line H1 was subjected to systematically varied shear flow, and mechanosensitive proteins were obtained by mass spectrometry (MS) analysis. Then, function enrichment analysis was performed to identify the enriched gene sets. Under a steady shear flow of 1.1 Pa for 24 h, protein expressions were further detected using western blotting (WB), quantitative real-time PCR (qPCR), and immunofluorescence (IF) staining. Meanwhile, the cells were treated with 200 nM trichostatin (TSA) for 1 h as positive control to test chromatin decondensation. Actin, DNA, and RNA were then visualized with TRITC-labeled phalloidin, Hoechst 33342, and SYTO® RNASelect™ green fluorescent cell stain (Life Technologies), respectively. In addition, cell stiffness was determined with atomic force microscopy (AFM) and annexin V-PE was used to determine the apoptosis with a flow cytometer (FCM). RESULTS Typical mechanosensitive proteins were unraveled upon mechanomics analysis under fluid shear related to hESCs in vivo. Functional analyses revealed significant alterations in histone acetylation, nuclear size, and cytoskeleton for hESC under shear flow. Shear flow was able to induce H2B acetylation and nuclear spreading by CFL2/F-actin cytoskeletal reorganization. The resulting chromatin decondensation and a larger nucleus readily accommodate signaling molecules and transcription factors. CONCLUSIONS Shear flow regulated chromatin dynamics in hESCs via cytoskeleton and nucleus alterations and consolidated their primed state.
Collapse
Affiliation(s)
- Jiawen Wang
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.,School of Engineering Science, University of Chinese Academy of Sciences, Beijing, China
| | - Yi Wu
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.,School of Engineering Science, University of Chinese Academy of Sciences, Beijing, China
| | - Xiao Zhang
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.,School of Engineering Science, University of Chinese Academy of Sciences, Beijing, China
| | - Fan Zhang
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.,School of Engineering Science, University of Chinese Academy of Sciences, Beijing, China
| | - Dongyuan Lü
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China.,School of Engineering Science, University of Chinese Academy of Sciences, Beijing, China
| | - Bing Shangguan
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yuxin Gao
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Mian Long
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory) and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, 100190, China. .,School of Engineering Science, University of Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
30
|
Akimoto Y, Yan K, Miura Y, Tsumoto H, Toda T, Fukutomi T, Sugahara D, Kudo A, Arai T, Chiba Y, Kaname S, Hart GW, Endo T, Kawakami H. O-GlcNAcylation and phosphorylation of β-actin Ser 199 in diabetic nephropathy. Am J Physiol Renal Physiol 2019; 317:F1359-F1374. [PMID: 31566433 PMCID: PMC6879942 DOI: 10.1152/ajprenal.00566.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 08/28/2019] [Accepted: 09/08/2019] [Indexed: 12/18/2022] Open
Abstract
The function of actin is regulated by various posttranslational modifications. We have previously shown that in the kidneys of nonobese type 2 diabetes model Goto-Kakizaki rats, increased O-GlcNAcylation of β-actin protein is observed. It has also been reported that both O-GlcNAcylation and phosphorylation occur on Ser199 of β-actin. However, their roles are not known. To elucidate their roles in diabetic nephropathy, we examined the rat kidney for changes in O-GlcNAcylation of Ser199 (gS199)-actin and in the phosphorylation of Ser199 (pS199)-actin. Both gS199- and pS199-actin molecules had an apparent molecular weight of 40 kDa and were localized as nonfilamentous actin in both the cytoplasm and nucleus. Compared with the normal kidney, the immunostaining intensity of gS199-actin increased in podocytes of the glomeruli and in proximal tubules of the diabetic kidney, whereas that of pS199-actin did not change in podocytes but decreased in proximal tubules. We confirmed that the same results could be observed in the glomeruli of the human diabetic kidney. In podocytes of glomeruli cultured in the presence of the O-GlcNAcase inhibitor Thiamet G, increased O-GlcNAcylation was accompanied by a concomitant decrease in the amount of filamentous actin and in morphological changes. Our present results demonstrate that dysregulation of O-GlcNAcylation and phosphorylation of Ser199 occurred in diabetes, which may contribute partially to the causes of the morphological changes in the glomeruli and tubules. gS199- and pS199-actin will thus be useful for the pathological evaluation of diabetic nephropathy.
Collapse
Affiliation(s)
- Yoshihiro Akimoto
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Kunimasa Yan
- Department of Pediatrics, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Yuri Miura
- Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Hiroki Tsumoto
- Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Tosifusa Toda
- Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Toshiyuki Fukutomi
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Daisuke Sugahara
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Akihiko Kudo
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Tomio Arai
- Department of Pathology, Tokyo Metropolitan Geriatric Hospital, Itabashi, Tokyo, Japan
| | - Yuko Chiba
- Department of Diabetes, Metabolism and Endocrinology, Tokyo Metropolitan Geriatric Hospital, Itabashi, Tokyo, Japan
| | - Shinya Kaname
- Department of Nephrology and Rheumatology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| | - Gerald W Hart
- Center for Complex Carbohydrates, University of Georgia, Athens, Georgia
| | - Tamao Endo
- Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Hayato Kawakami
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan
| |
Collapse
|
31
|
HnRNPA1 interacts with G-quadruplex in the TRA2B promoter and stimulates its transcription in human colon cancer cells. Sci Rep 2019; 9:10276. [PMID: 31311954 PMCID: PMC6635519 DOI: 10.1038/s41598-019-46659-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 04/24/2019] [Indexed: 12/15/2022] Open
Abstract
The human TRA2B gene consists of 10 exons and 9 introns and produces 5 splice isoforms (TRA2β1 to TRA2β5). TRA2B exon 2 encodes multiple premature termination codons. TRA2β1 lacks exon 2 and is translated into a functional transformer 2β (Tra2β) protein, whereas TRA2β4 contains 10 exons and works as a functional RNA. Overexpressed Tra2β and ectopic expression of TRA2β4 may be oncogenic. We found that heterogeneous nuclear ribonucleoprotein (hnRNP)A1 and hnRNPU interacted with TRA2β4 exon 2. Minigene assays revealed that hnRNPA1 facilitated inclusion of exon 2, whereas hnRNPU promoted its skipping. However, knockdown of hnRNPA1 or hnRNPU reduced both TRA2β1 and TRA2β4 levels, and overexpression of these hnRNPs increased levels of both isoforms, suggesting that hnRNPA1 and hnRNPU mainly regulate the transcription of TRA2B. In fact, hnRNPA1 and hnRNPU positively regulated the promoter activity of TRA2B. Circular dichroism analyses, electrophoretic mobility shift assays and chromatin immunoprecipitation assays demonstrated the presence of G-quadruplex (G4) formation in the promoter of TRA2B. Formation of G4 suppressed TRA2B transcription, whereas hnRNPA1, but not hnRNPU, interacted with the G4 to facilitate transcription. Our results suggest that hnRNPA1 may modulate TRA2B transcription through its regulation of G4 formation in its promoter in colon cancer cells.
Collapse
|
32
|
Sidorenko E, Vartiainen MK. Nucleoskeletal regulation of transcription: Actin on MRTF. Exp Biol Med (Maywood) 2019; 244:1372-1381. [PMID: 31142145 DOI: 10.1177/1535370219854669] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Myocardin-related transcription factor A (MRTF-A) and serum response factor (SRF) form an essential transcriptional complex that regulates the expression of many cytoskeletal genes in response to dynamic changes in the actin cytoskeleton. The nucleoskeleton, a “dynamic network of networks,” consists of numerous proteins that contribute to nuclear shape and to its various functions, including gene expression. In this review, we will discuss recent work that has identified many nucleoskeletal proteins, such as nuclear lamina and lamina-associated proteins, nuclear actin, and the linker of the cytoskeleton and nucleoskeleton complex as important regulators of MRTF-A/SRF transcriptional activity, especially in the context of mechanical control of transcription. Impact statement Regulation of gene expression is a fundamental cellular process that ensures the appropriate response of a cell to its surroundings. Alongside biochemical signals, mechanical cues, such as substrate rigidity, have been recognized as key regulators of gene expression. Nucleoskeletal components play an important role in mechanoresponsive transcription, particularly in controlling the activity of MRTF-A/SRF transcription factors. This ensures that the cell can balance the internal and external mechanical forces by fine-tuning the expression of cytoskeletal genes.
Collapse
Affiliation(s)
- Ekaterina Sidorenko
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| | - Maria K Vartiainen
- Institute of Biotechnology, Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| |
Collapse
|
33
|
Ilicheva NV, Pochukalina GN, Podgornaya OI. Actin depolymerization disrupts karyosphere capsule integrity but not residual transcription in late oocytes of the grass frog Rana temporaria. J Cell Biochem 2019; 120:15057-15068. [PMID: 31081178 DOI: 10.1002/jcb.28767] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 12/30/2022]
Abstract
Late diplotene oocytes are characterized by an essential decrease in transcriptional activity. At this time, chromosomes condense and form a compact structure named a karyosphere. The karyosphere of grass frogs Rana temporaria is surrounded by a fibrillar karyosphere capsule (KC). One of the main protein constituents of R. temporaria KC is actin. In this study, we used antibodies against different actin epitopes to trace different forms of actin in the KC. We also investigated the effect of F-actin depolymerization on the oocyte nuclear structures and transcription of chromatin DNA and rDNA in the amplified nucleoli. It was determined that disruption of actin filaments leads to chromosome shrinkage, nucleoli fusion, and distortion of the KC structure, but does not inhibit residual transcription in both the karyosphere and the nucleoli.
Collapse
Affiliation(s)
- Nadya V Ilicheva
- Institute of Cytology of Russian Academy of Sciences, Saint Petersburg, Russia
| | | | - Olga I Podgornaya
- Institute of Cytology of Russian Academy of Sciences, Saint Petersburg, Russia.,Saint Petersburg University, Saint Petersburg, Russia.,Far Eastern Federal University, Vladivostok, Russia
| |
Collapse
|
34
|
Viita T, Kyheröinen S, Prajapati B, Virtanen J, Frilander MJ, Varjosalo M, Vartiainen MK. Nuclear actin interactome analysis links actin to KAT14 histone acetyl transferase and mRNA splicing. J Cell Sci 2019; 132:jcs.226852. [PMID: 30890647 PMCID: PMC6503952 DOI: 10.1242/jcs.226852] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 03/05/2019] [Indexed: 12/25/2022] Open
Abstract
In addition to its essential functions within the cytoskeleton, actin also localizes to the cell nucleus, where it is linked to many important nuclear processes from gene expression to maintenance of genomic integrity. However, the molecular mechanisms by which actin operates in the nucleus remain poorly understood. Here, we have used two complementary mass spectrometry (MS) techniques, AP-MS and BioID, to identify binding partners for nuclear actin. Common high-confidence interactions highlight the role of actin in chromatin-remodeling complexes and identify the histone-modifying complex human Ada-Two-A-containing (hATAC) as a novel actin-containing nuclear complex. Actin binds directly to the hATAC subunit KAT14, and modulates its histone acetyl transferase activity in vitro and in cells. Transient interactions detected through BioID link actin to several steps of transcription as well as to RNA processing. Alterations in nuclear actin levels disturb alternative splicing in minigene assays, likely by affecting the transcription elongation rate. This interactome analysis thus identifies both novel direct binding partners and functional roles for nuclear actin, as well as forms a platform for further mechanistic studies on how actin operates during essential nuclear processes.This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Tiina Viita
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| | - Salla Kyheröinen
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| | - Bina Prajapati
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| | - Jori Virtanen
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| | - Mikko J Frilander
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| | - Markku Varjosalo
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland.,Proteomics Unit, University of Helsinki, Helsinki 00014, Finland
| | - Maria K Vartiainen
- Institute of Biotechnology, University of Helsinki, Helsinki 00014, Finland .,Helsinki Institute of Life Science, University of Helsinki, Helsinki 00014, Finland
| |
Collapse
|
35
|
Baculovirus IE2 Interacts with Viral DNA through Daxx To Generate an Organized Nuclear Body Structure for Gene Activation in Vero Cells. J Virol 2019; 93:JVI.00149-19. [PMID: 30728268 DOI: 10.1128/jvi.00149-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 01/31/2019] [Indexed: 12/14/2022] Open
Abstract
Upon virus infection of a cell, the uncoated DNA is usually blocked by the host intrinsic immune system inside the nucleus. Although it is crucial for the virus to counteract the host intrinsic immune system and access its genome, little is known about how viruses can knock down host restriction and identify their blocked genomes for later viral gene activation and replication. We found that upon baculovirus transduction into Vero E6 cells, the invading viral DNA is trapped by the cellular death domain-associated protein (Daxx) and histone H3.3 in the nucleus, resulting in gene inactivation. IE2, a baculovirus transactivator, targets host Daxx through IE2 SUMO-interacting motifs (SIMs) to indirectly access viral DNA and forms unique nuclear body structures, which we term clathrate cage-like apparatus (CCLAs), at the early transduction stage. At the later transduction stage, CCLAs gradually enlarge, and IE2 continues to closely interact with viral DNA but no longer associates with Daxx. The association with Daxx is essential for IE2 CCLA formation, and the enlarged CCLAs are capable of transactivating viral but not chromosomal DNA of Vero E6 cells. Our study reveals that baculovirus IE2 counteracts the cellular intrinsic immune system by specifically targeting Daxx and H3.3 to associate with viral DNA indirectly and efficiently. IE2 then utilizes this association with viral DNA to establish a unique CCLA cellular nanomachinery, which is visible under light microscopy as an enclosed environment for proper viral gene expression.IMPORTANCE The major breakthrough of this work is that viral protein IE2 localizes and transactivates its own viral DNA through a most unlikely route, i.e., host proteins Daxx and H3.3, which are designed to efficiently restrict viral DNA from expression. By interacting with these host intrinsic immune factors, IE2 can thus target the viral DNA and then form a unique spherical nuclear body, which we name the CCLA, to enclose the viral DNA and necessary factors to assist in high-level transactivation. Our study represents one of the most complete investigations of nuclear body formation. In addition, so far only RNA or protein molecules have been reported as potential nucleators for initiating nuclear body formation; our study may represent the first example showing that DNA can be a nucleator for a new class of nuclear body formation.
Collapse
|
36
|
Tsai E, Casaccia P. Mechano-modulation of nuclear events regulating oligodendrocyte progenitor gene expression. Glia 2019; 67:1229-1239. [PMID: 30734358 DOI: 10.1002/glia.23595] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 01/03/2019] [Accepted: 01/14/2019] [Indexed: 12/20/2022]
Abstract
Oligodendrocytes differentiate from oligodendrocyte progenitor cells (OPCs) in response to distinct extracellular signals. This process requires changes in gene expression resulting from the interplay between transcription factors and epigenetic modulators. Extracellular signals include chemical and physical stimuli. This review focuses on the signaling mechanisms activated in oligodendrocyte progenitors in response to mechanical forces. Of particular interest is a better understanding on how these forces are transduced into the OPC nuclei and subsequently reshape their epigenetic landscape. Here we will introduce the concept of epigenetic regulation of gene expression, first in general and then focusing on the oligodendrocyte lineage. We will then review the current literature on mechano-transduction in distinct cell types, followed by pathways identified in myelinating oligodendrocytes and their progenitors. Overall, the reader will be provided with a comprehensive review of the signaling pathways which allow oligodendrocyte progenitors to "sense" physical forces and transduce them into patterns of gene expression.
Collapse
Affiliation(s)
- Eric Tsai
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York.,Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Patrizia Casaccia
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York.,Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York.,Department of Biology and Biochemistry, Neuroscience Initiative at the Advanced Science Research Center of the Graduate Center of The City University of New York, New York
| |
Collapse
|
37
|
AKT/protein kinase B associates with β-actin in the nucleus of melanoma cells. Biosci Rep 2019; 39:BSR20181312. [PMID: 30643008 PMCID: PMC6356016 DOI: 10.1042/bsr20181312] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/21/2018] [Accepted: 01/07/2019] [Indexed: 12/19/2022] Open
Abstract
The serine-threonine kinase AKT/PKB is a critical regulator of various essential cellular processes, and dysregulation of AKT has been implicated in many diseases, including cancer. Despite AKT action is known to function mainly in the cytoplasm, AKT has been reported to translocate to the nucleus. However, very little is known about the mechanism required for the nuclear import of AKT as well as its function in this cellular compartment. In the present study, we characterized the presence of endogenous nuclear AKT in human melanoma cells and addressed the possible role of AKT by exploring its potential association with key interaction nuclear partners. Confocal and Western blot analyses showed that both phosphorylated and non-phosphorylated forms of AKT are present in melanoma cells nuclei. Using mass spectrometry in combination with protein-crosslinking and co-immunoprecipitation, we identified a series of putative protein partners of nuclear AKT, including heterogeneous nuclear ribonucleoprotein (hnRNP), cytoskeleton proteins β-actin, γ-actin, β-actin-like 2 and vimentin. Confocal microscopy and biochemical analyses validated β-actin as a new nuclear AKT-interacting partner. Cofilin and active RNA Polymerase II, two proteins that have been described to interact and work in concert with nuclear actin in transcription regulation, were also found associated with nuclear AKT. Overall, the present study uncovered a yet unrecognized nuclear coupling of AKT and provides insights into the involvement of AKT in the interaction network of nuclear actin.
Collapse
|
38
|
Kumarasinghe N, Moss WN. Analysis of a structured intronic region of the LMP2 pre-mRNA from EBV reveals associations with human regulatory proteins and nuclear actin. BMC Res Notes 2019; 12:33. [PMID: 30658689 PMCID: PMC6339298 DOI: 10.1186/s13104-019-4070-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 01/11/2019] [Indexed: 01/07/2023] Open
Abstract
Objective The pre-mRNA of the Epstein–Barr virus LMP2 (latent membrane protein 2) has a region of unusual RNA structure that partially spans two consecutive exons and the entire intervening intron; suggesting RNA folding might affect splicing—particularly via interactions with human regulatory proteins. To better understand the roles of protein associations with this structured intronic region, we undertook a combined bioinformatics (motif searching) and experimental analysis (biotin pulldowns and RNA immunoprecipitations) of protein binding. Result Characterization of the ribonucleoprotein composition of this region revealed several human proteins as interactors: regulatory proteins hnRNP A1 (heterogeneous nuclear ribonucleoprotein A1), hnRNP U, HuR (human antigen R), and PSF (polypyrimidine tract-binding protein-associated splicing factor), as well as, unexpectedly, the cytoskeletal protein actin. Treatment of EBV-positive cells with drugs that alter actin polymerization specifically showed marked effects on splicing in this region. This suggests a potentially novel role for nuclear actin in regulation of viral RNA splicing. Electronic supplementary material The online version of this article (10.1186/s13104-019-4070-1) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Nuwanthika Kumarasinghe
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA, 50011, USA
| | - Walter N Moss
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA, 50011, USA.
| |
Collapse
|
39
|
Okamoto Y, Abe M, Itaya A, Tomida J, Ishiai M, Takaori-Kondo A, Taoka M, Isobe T, Takata M. FANCD2 protects genome stability by recruiting RNA processing enzymes to resolve R-loops during mild replication stress. FEBS J 2018; 286:139-150. [PMID: 30431240 DOI: 10.1111/febs.14700] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/02/2018] [Accepted: 11/12/2018] [Indexed: 01/19/2023]
Abstract
R-loops, which consist of DNA : RNA hybrids and displaced single-strand DNA, are a major threat to genome stability. We have previously reported that a key Fanconi anemia protein, FANCD2, accumulates on large fragile genes during mild replication stress in a manner depending on R-loops. In this study, we found that FANCD2 suppresses R-loop levels. Furthermore, we identified FANCD2 interactions with RNA processing factors, including hnRNP U and DDX47. Our data suggest that FANCD2, which accumulates with R-loops in chromatin, recruits these factors and thereby promotes efficient processing of long RNA transcripts. This may lead to a reduction in transcription-replication collisions, as detected by PLA between PCNA and RNA Polymerase II, and hence, lowered R-loop levels. We propose that this mechanism might contribute to maintenance of genome stability during mild replication stress.
Collapse
Affiliation(s)
- Yusuke Okamoto
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Japan.,Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, Japan
| | - Masako Abe
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Japan
| | - Akiko Itaya
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Japan
| | - Junya Tomida
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Japan.,Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd, Charlotte, NC, 28223, USA
| | - Masamichi Ishiai
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Japan.,National Cancer Center Research Institute, Tokyo, 104-0045, Japan
| | - Akifumi Takaori-Kondo
- Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, Japan
| | - Masato Taoka
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Japan
| | - Toshiaki Isobe
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Japan
| | - Minoru Takata
- Laboratory of DNA Damage Signaling, Department of Late Effects Studies, Radiation Biology Center, Graduate School of Biostudies, Kyoto University, Japan
| |
Collapse
|
40
|
An actin-based nucleoskeleton involved in gene regulation and genome organization. Biochem Biophys Res Commun 2018; 506:378-386. [DOI: 10.1016/j.bbrc.2017.11.206] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Accepted: 11/30/2017] [Indexed: 12/21/2022]
|
41
|
Sokolova M, Moore HM, Prajapati B, Dopie J, Meriläinen L, Honkanen M, Matos RC, Poukkula M, Hietakangas V, Vartiainen MK. Nuclear Actin Is Required for Transcription during Drosophila Oogenesis. iScience 2018; 9:63-70. [PMID: 30384134 PMCID: PMC6214840 DOI: 10.1016/j.isci.2018.10.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/28/2018] [Accepted: 10/10/2018] [Indexed: 01/30/2023] Open
Abstract
Actin has been linked to processes spanning the whole gene expression cascade, from regulating specific transcription factors, such as myocardin-related transcription factor, to chromatin remodeling and RNA polymerase function. However, whether actin controls the transcription of only specific genes or has a global role in gene expression has remained elusive. Our genome-wide analysis reveals, for the first time, that actin interacts with essentially all transcribed genes in Drosophila ovaries. Actin co-occupies the majority of gene promoters together with Pol II, and on highly expressed genes, these two proteins also associate with gene bodies. Mechanistically, actin is required for Pol II recruitment to gene bodies, and manipulation of nuclear transport factors for actin leads to the decreased expression of eggshell genes. Collectively, these results uncover a global role for actin in transcription and demonstrate the in vivo importance of balanced nucleocytoplasmic shuttling of actin in the transcriptional control of a developmental process. Genome-wide analysis shows actin on all transcribed genes Actin binds with RNA polymerase II near transcription start sites of most genes On highly expressed genes, actin is also found on the gene bodies Nuclear transport of actin is required for transcription during fly development
Collapse
Affiliation(s)
- Maria Sokolova
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Henna M Moore
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Bina Prajapati
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Joseph Dopie
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Leena Meriläinen
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Mikko Honkanen
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Rita Cerejeira Matos
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
| | - Minna Poukkula
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland
| | - Ville Hietakangas
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland; Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
| | - Maria K Vartiainen
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Viikinkaari 5, 00014 Helsinki, Finland.
| |
Collapse
|
42
|
Nuclear actin: ancient clue to evolution in eukaryotes? Histochem Cell Biol 2018; 150:235-244. [DOI: 10.1007/s00418-018-1693-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2018] [Indexed: 12/31/2022]
|
43
|
Mahalingam S, Ordaz JD, Low PS. Targeting of a Photosensitizer to the Mitochondrion Enhances the Potency of Photodynamic Therapy. ACS OMEGA 2018; 3:6066-6074. [PMID: 30023938 PMCID: PMC6045488 DOI: 10.1021/acsomega.8b00692] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 05/23/2018] [Indexed: 05/24/2023]
Abstract
Photodynamic therapy (PDT) involves use of a photosensitizer, whose activation with light leads to the production of singlet oxygen (SOS), generation of reactive oxygen species (ROS), and initiation of associated cell toxicity. Because a cell's mitochondria constitute sites where oxygen levels are high, ROS can be readily produced, and apoptosis is commonly initiated. Therefore, an ideal PDT agent might be a potent photosensitizer that could naturally accumulate in mitochondria. Although a number of mitochondria-targeting moieties, including triphenylphosphine, guanidinium, and bisguanidium, have been identified, a quantitative comparison of their efficacies in targeting mitochondria has not been performed. In this study, we have prepared triphenylphosphine, guanidinium, and bisguanidium derivatives of the FDA-approved PDT agent verteporfin (Visudyne, benzoporphyrin derivative-monoacid ring A: BPD-MA) and compared their abilities to induce the intracellular perturbations common to potent PDT agents. Cellular parameters examined included subcellular localization of the verteporfin, real-time monitoring of SOS production, quantitation of reactive oxygen species (ROS) generation, analysis of mitochondria and chromatin integrity, characterization of cytoskeletal disruption and evaluation of cytochrome C release as a measure of apoptosis. An analysis of these parameters demonstrates that the triphenylphosphine derivative (0323) has better mitochondria-targeting efficacy, SOS production, and mitochondria membrane toxicity than either unmodified verteporfin or its guanidinium derivatives. Consistent with this potency, 0323 also induced the most prominent mitochondria swelling, actin depolymerization, pyknosis, and cytochrome C release. We conclude that triphenylphosphine has a better mitochondria-targeting moiety than guanidinium or bis-guanidinium and those PDT photosensitizers with improved cytotoxicities can be prepared by conjugating a mitochondria-targeting moiety to the desired photosensitizer.
Collapse
Affiliation(s)
- Sakkarapalayam
M. Mahalingam
- Department
of Chemistry and Institute for Drug Discovery, Purdue University, 720
Clinic Drive, West Lafayette, Indiana 47907, United
States
| | - Josue D. Ordaz
- Department
of Chemistry and Institute for Drug Discovery, Purdue University, 720
Clinic Drive, West Lafayette, Indiana 47907, United
States
- Indiana
University School of Medicine, 340 W 10th Street #6200, Indianapolis, Indiana 46202, United States
| | - Philip S. Low
- Department
of Chemistry and Institute for Drug Discovery, Purdue University, 720
Clinic Drive, West Lafayette, Indiana 47907, United
States
| |
Collapse
|
44
|
Charó NL, Galigniana NM, Piwien-Pilipuk G. Heterochromatin protein (HP)1γ is not only in the nucleus but also in the cytoplasm interacting with actin in both cell compartments. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1865:432-443. [PMID: 29208528 DOI: 10.1016/j.bbamcr.2017.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 11/07/2017] [Accepted: 11/30/2017] [Indexed: 12/20/2022]
Abstract
Confocal and electron microscopy images, and WB analysis of cellular fractions revealed that HP1γ is in the nucleus but also in the cytoplasm of C2C12 myoblasts, myotubes, skeletal and cardiac muscles, N2a, HeLa and HEK293T cells. Signal specificity was tested with different antibodies and by HP1γ knockdown. Leptomycin B treatment of myoblasts increased nuclear HP1γ, suggesting that its nuclear export is Crm-1-dependent. HP1γ exhibited a filamentous pattern of staining partially co-localizing with actin in the cytoplasm of myotubes and myofibrils. Immunoelectron microscopic analysis showed high-density immunogold particles that correspond to HP1γ localized to the Z-disk and A-band of the sarcomere of skeletal muscle. HP1γ partially co-localized with actin in C2C12 myotubes and murine myofibrils. Importantly, actin co-immunoprecipitated with HP1γ in the nuclear and cytosolic fractions of myoblasts. Actin co-immunoprecipitated with HP1γ in myoblasts incubated in the absence or presence of the actin depolymerizing agent cytochalasin D, suggesting that HP1γ may interact with G-and F-actin. In the cytoplasm, HP1γ was associated to the perinuclear actin cap that controls nuclear shape and position. In the nucleus, re-ChIP assays showed that HP1γ-actin associates to the promoter and transcribed regions of the house keeping gene GAPDH, suggesting that HP1γ may function as a scaffold protein for the recruitment of actin to control gene expression. When HP1γ was knocked-down, myoblasts were unable to differentiate or originated thin myotubes. In summary, HP1γ is present in the nucleus and the cytoplasm interacting with actin, a protein complex that may exert different functions depending on its subcellular localization.
Collapse
Affiliation(s)
- Nancy L Charó
- Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Natalia M Galigniana
- Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Graciela Piwien-Pilipuk
- Laboratory of Nuclear Architecture, Instituto de Biología y Medicina Experimental (IByME) - CONICET, Ciudad Autónoma de Buenos Aires, Argentina.
| |
Collapse
|
45
|
Kuznetsov NV, Almuzzaini B, Kritikou JS, Baptista MAP, Oliveira MMS, Keszei M, Snapper SB, Percipalle P, Westerberg LS. Nuclear Wiskott-Aldrich syndrome protein co-regulates T cell factor 1-mediated transcription in T cells. Genome Med 2017; 9:91. [PMID: 29078804 PMCID: PMC5660450 DOI: 10.1186/s13073-017-0481-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 10/11/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The Wiskott-Aldrich syndrome protein (WASp) family of actin-nucleating factors are present in the cytoplasm and in the nucleus. The role of nuclear WASp for T cell development remains incompletely defined. METHODS We performed WASp chromatin immunoprecipitation and deep sequencing (ChIP-seq) in thymocytes and spleen CD4+ T cells. RESULTS WASp was enriched at genic and intergenic regions and associated with the transcription start sites of protein-coding genes. Thymocytes and spleen CD4+ T cells showed 15 common WASp-interacting genes, including the gene encoding T cell factor (TCF)12. WASp KO thymocytes had reduced nuclear TCF12 whereas thymocytes expressing constitutively active WASpL272P and WASpI296T had increased nuclear TCF12, suggesting that regulated WASp activity controlled nuclear TCF12. We identify a putative DNA element enriched in WASp ChIP-seq samples identical to a TCF1-binding site and we show that WASp directly interacted with TCF1 in the nucleus. CONCLUSIONS These data place nuclear WASp in proximity with TCF1 and TCF12, essential factors for T cell development.
Collapse
Affiliation(s)
- Nikolai V Kuznetsov
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Bader Almuzzaini
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, 171 77, Sweden.,King Abdullah International Medical Research Center/King Saud bin Abdulaziz University for Health Sciences Medical Genomic Research Department, MNGHA, Riyadh, Saudi Arabia
| | - Joanna S Kritikou
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Marisa A P Baptista
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, Stockholm, 171 77, Sweden.,Institute for Virology and Immunobiology, University of Würzburg, 97078, Würzburg, Germany
| | - Mariana M S Oliveira
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Marton Keszei
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Scott B Snapper
- Gastroenterology Division, Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Piergiorgio Percipalle
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, 171 77, Sweden.,Biology Program, New York University Abu Dhabi (NYUAD), P.O. Box 129188, Abu Dhabi, United Arab Emirates.,Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
| | - Lisa S Westerberg
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, Stockholm, 171 77, Sweden.
| |
Collapse
|
46
|
Misu S, Takebayashi M, Miyamoto K. Nuclear Actin in Development and Transcriptional Reprogramming. Front Genet 2017; 8:27. [PMID: 28326098 PMCID: PMC5339334 DOI: 10.3389/fgene.2017.00027] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 02/20/2017] [Indexed: 12/20/2022] Open
Abstract
Actin is a highly abundant protein in eukaryotic cells and dynamically changes its polymerized states with the help of actin-binding proteins. Its critical function as a constituent of cytoskeleton has been well-documented. Growing evidence demonstrates that actin is also present in nuclei, referred to as nuclear actin, and is involved in a number of nuclear processes, including transcriptional regulation and chromatin remodeling. The contribution of nuclear actin to transcriptional regulation can be explained by its direct interaction with transcription machineries and chromatin remodeling factors and by controlling the activities of transcription factors. In both cases, polymerized states of nuclear actin affect the transcriptional outcome. Nuclear actin also plays an important role in activating strongly silenced genes in somatic cells for transcriptional reprogramming. When these nuclear functions of actin are considered, it is plausible to speculate that nuclear actin is also implicated in embryonic development, in which numerous genes need to be activated in a well-coordinated manner. In this review, we especially focus on nuclear actin's roles in transcriptional activation, reprogramming and development, including stem cell differentiation and we discuss how nuclear actin can be an important player in development and cell differentiation.
Collapse
Affiliation(s)
- Shinji Misu
- Laboratory of Molecular Developmental Biology, Faculty of Biology-Oriented Science and Technology, Kindai University Kinokawa-shi, Japan
| | - Marina Takebayashi
- Laboratory of Molecular Developmental Biology, Faculty of Biology-Oriented Science and Technology, Kindai University Kinokawa-shi, Japan
| | - Kei Miyamoto
- Laboratory of Molecular Developmental Biology, Faculty of Biology-Oriented Science and Technology, Kindai University Kinokawa-shi, Japan
| |
Collapse
|
47
|
Knöll B, Beck H. The cytoskeleton and nucleus: the role of actin as a modulator of neuronal gene expression. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s13295-010-0013-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Abstract
Actin, arranged for example in stress fibres, provides a fundamental cytoskeletal framework function to all cell types. Notably, there is now mounting evidence that, in addition to cytoplasmic cytoskeletal regulation, actin treadmilling provides a signal modulating nuclear gene expression. In altering gene regulation, cytoplasmic and most likely also a nucleus-resident actin provides an additional (gene) regulatory twist to cell motility. So far, the transcription factor serum response factor (SRF) alongside its myocardin-related transcription factor (MRTF) cofactors has emerged as the main target of actin dynamics. In this review, we discuss the impact of actin signalling on nuclear gene expression in the nervous system, where the actin-MRTF-SRF module contributes to various processes including neuronal motility.
Collapse
Affiliation(s)
- B. Knöll
- Institute for Physiological Chemistry, University of Ulm Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - H. Beck
- Institute for Physiological Chemistry, University of Ulm Albert-Einstein-Allee 11, 89081 Ulm, Germany
| |
Collapse
|
48
|
Diverse functions for different forms of nuclear actin. Curr Opin Cell Biol 2017; 46:33-38. [PMID: 28092729 DOI: 10.1016/j.ceb.2016.12.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 11/23/2016] [Accepted: 12/12/2016] [Indexed: 12/31/2022]
Abstract
In addition to its essential roles as part of the cytoskeleton, actin has also been linked to many processes in the nucleus. Recent data has demonstrated the presence of both monomeric and polymeric actin in the nucleus, and implied distinct functional roles for these actin pools. Monomeric actin seems to be involved in regulation of gene expression through transcription factors, chromatin regulating complexes and RNA polymerases. In addition to cytoplasmic actin regulators, nuclear proteins, such as emerin, can regulate actin polymerization properties specifically in this compartment. Besides of structural roles, nuclear actin filaments may be required for organizing the nuclear contents and for the maintenance of genomic integrity.
Collapse
|
49
|
Abstract
Although most people still associate actin mainly with the cytoskeleton, several lines of evidence, with the earliest studies dating back to decades ago, have emphasized the importance of actin also inside the cell nucleus. Actin has been linked to many gene expression processes from gene activation to chromatin remodeling, but also to maintenance of genomic integrity and intranuclear movement of chromosomes and chromosomal loci. Recent advances in visualizing different forms and dynamic properties of nuclear actin have clearly advanced our understanding of the basic concepts by which actin operates in the nucleus. In this chapter we address the different breakthroughs in nuclear actin studies, as well as discuss the regulation nuclear actin and the importance of nuclear actin dynamics in relation to its different nuclear functions. Our aim is to highlight the fact that actin should be considered as an essential component of the cell nucleus, and its nuclear actions should be taken into account also in experiments on cytoplasmic actin networks.
Collapse
Affiliation(s)
- Tiina Viita
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 56, Helsinki, Finland
| | - Maria K Vartiainen
- Program in Cell and Molecular Biology, Institute of Biotechnology, University of Helsinki, 56, Helsinki, Finland.
| |
Collapse
|
50
|
Insights into a novel nuclear function for Fascin in the regulation of the amino-acid transporter SLC3A2. Sci Rep 2016; 6:36699. [PMID: 27819326 PMCID: PMC5098188 DOI: 10.1038/srep36699] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 10/19/2016] [Indexed: 01/08/2023] Open
Abstract
Fascin 1 (FSCN1) is a cytoskeleton-associated protein recognized to function primarily in the regulation of cytoskeleton structure and formation of plasma membrane protrusions. Here we report a novel nuclear function for Fascin 1. Biochemical studies and genome wide localization using ChIP-seq identified phosphorylated Fascin 1 (pFascin) in complexes associated with transcription and that it co-localizes with histone H3 Lys4 trimethylation (H3K4me3) on chromatin. Gene expression profiling identified genes affected by Fascin 1 including SLC3A2, a gene encoding for a plasma membrane transporter that regulates intracellular amino acid levels. RbBP5, a subunit of the H3K4 histone methyltransferase (HMT) complex was found to interact with Fascin 1 supporting its role in H3K4me3 establishment at target genes. Moreover, we show that changes to SLC3A2 levels affect amino acid-mediated mTORC1 activation. These results reveal that Fascin 1 has a yet undiscovered nuclear function as an epigenetic modulator of genes essential for amino acid metabolism.
Collapse
|