1
|
Fernandez MK, Sinha M, Zidan M, Renz M. Nuclear actin filaments - a historical perspective. Nucleus 2024; 15:2320656. [PMID: 38384139 PMCID: PMC10885181 DOI: 10.1080/19491034.2024.2320656] [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: 11/22/2023] [Accepted: 02/14/2024] [Indexed: 02/23/2024] Open
Abstract
The view on nuclear filaments formed by non-skeletal β-actin has significantly changed over the decades. Initially, filamentous actin was observed in amphibian oocyte nuclei and only under specific cell stress conditions in mammalian cell nuclei. Improved labeling and imaging technologies have permitted insights into a transient but microscopically apparent filament network that is relevant for chromatin organization, biomechanics of the mammalian cell nucleus, gene expression, and DNA damage repair. Here, we will provide a historical perspective on the developing insight into nuclear actin filaments.
Collapse
Affiliation(s)
| | - Molika Sinha
- Gynecologic Oncology Division, School of Medicine Stanford University, Palo Alto, CA, USA
| | - Mia Zidan
- Gynecologic Oncology Division, School of Medicine Stanford University, Palo Alto, CA, USA
| | - Malte Renz
- Gynecologic Oncology Division, School of Medicine Stanford University, Palo Alto, CA, USA
| |
Collapse
|
2
|
Rivard RS, Chang YC, Ragland RL, Thu YM, Kassab M, Mandal RS, Van Riper SK, Kulej K, Higgins L, Markowski TM, Shang D, Hedberg J, Erber L, Garcia B, Chen Y, Bielinsky AK, Brown EJ. Improved detection of DNA replication fork-associated proteins. Cell Rep 2024; 43:114178. [PMID: 38703364 DOI: 10.1016/j.celrep.2024.114178] [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: 07/12/2022] [Revised: 03/06/2024] [Accepted: 04/16/2024] [Indexed: 05/06/2024] Open
Abstract
Innovative methods to retrieve proteins associated with actively replicating DNA have provided a glimpse into the molecular dynamics of replication fork stalling. We report that a combination of density-based replisome enrichment by isolating proteins on nascent DNA (iPOND2) and label-free quantitative mass spectrometry (iPOND2-DRIPPER) substantially increases both replication factor yields and the dynamic range of protein quantification. Replication protein abundance in retrieved nascent DNA is elevated up to 300-fold over post-replicative controls, and recruitment of replication stress factors upon fork stalling is observed at similar levels. The increased sensitivity of iPOND2-DRIPPER permits direct measurement of ubiquitination events without intervening retrieval of diglycine tryptic fragments of ubiquitin. Using this approach, we find that stalled replisomes stimulate the recruitment of a diverse cohort of DNA repair factors, including those associated with poly-K63-ubiquitination. Finally, we uncover the temporally controlled association of stalled replisomes with nuclear pore complex components and nuclear cytoskeleton networks.
Collapse
Affiliation(s)
- Rebecca S Rivard
- Department of Cancer Biology and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ya-Chu Chang
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Ryan L Ragland
- Department of Cancer Biology and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yee-Mon Thu
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Muzaffer Kassab
- Department of Cancer Biology and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rahul Shubhra Mandal
- Department of Cancer Biology and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Susan K Van Riper
- University of Minnesota Informatics Institute, University of Minnesota, Minneapolis, MN, USA
| | - Katarzyna Kulej
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - LeeAnn Higgins
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Todd M Markowski
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - David Shang
- Department of Cancer Biology and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jack Hedberg
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Luke Erber
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Benjamin Garcia
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yue Chen
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA
| | - Anja-Katrin Bielinsky
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, USA.
| | - Eric J Brown
- Department of Cancer Biology and the Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
3
|
Vivo M, Rosti V, Cervone S, Lanzuolo C. Chromatin plasticity in mechanotransduction. Curr Opin Cell Biol 2024; 88:102376. [PMID: 38810318 DOI: 10.1016/j.ceb.2024.102376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/24/2024] [Accepted: 05/07/2024] [Indexed: 05/31/2024]
Abstract
Living organisms can detect and respond to physical forces at the cellular level. The pathways that transmit these forces to the nucleus allow cells to react quickly and consistently to environmental changes. Mechanobiology involves the interaction between physical forces and biological processes and is crucial for driving embryonic development and adapting to environmental cues during adulthood. Molecular studies have shown that cells can sense mechanical signals directly through membrane receptors linked to the cytoskeleton or indirectly through biochemical cascades that can influence gene expression for environmental adaptation. This review will explore the role of epigenetic modifications, emphasizing the 3D genome architecture and nuclear structures as responders to mechanical stimuli, which ensure cellular memory and adaptability. Understanding how mechanical cues are transduced and regulate cell functioning, governing processes such as cell programming and reprogramming, is essential for advancing our knowledge of human diseases.
Collapse
Affiliation(s)
- Maria Vivo
- Università degli Studi di Salerno, Fisciano, Italy.
| | - Valentina Rosti
- Institute of Biomedical Technologies, National Research Council (CNR), Milan, Italy; INGM Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Sara Cervone
- INGM Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy
| | - Chiara Lanzuolo
- Institute of Biomedical Technologies, National Research Council (CNR), Milan, Italy; INGM Istituto Nazionale Genetica Molecolare Romeo ed Enrica Invernizzi, Milan, Italy.
| |
Collapse
|
4
|
Nowak J, Lenartowski R, Kalita K, Lehka L, Karatsai O, Lenartowska M, Rędowicz MJ. Myosin VI in the nucleolus of neurosecretory PC12 cells: its involvement in the maintenance of nucleolar structure and ribosome organization. Front Physiol 2024; 15:1368416. [PMID: 38774650 PMCID: PMC11106421 DOI: 10.3389/fphys.2024.1368416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 04/01/2024] [Indexed: 05/24/2024] Open
Abstract
We have previously shown that unconventional myosin VI (MVI), a unique actin-based motor protein, shuttles between the cytoplasm and nucleus in neurosecretory PC12 cells in a stimulation-dependent manner and interacts with numerous proteins involved in nuclear processes. Among the identified potential MVI partners was nucleolin, a major nucleolar protein implicated in rRNA processing and ribosome assembly. Several other nucleolar proteins such as fibrillarin, UBF (upstream binding factor), and B23 (also termed nucleophosmin) have been shown to interact with MVI. A bioinformatics tool predicted the presence of the nucleolar localization signal (NoLS) within the MVI globular tail domain, and immunostaining confirmed the presence of MVI within the nucleolus. Depletion of MVI, previously shown to impair PC12 cell proliferation and motility, caused disorganization of the nucleolus and rough endoplasmic reticulum (rER). However, lack of MVI does not affect nucleolar transcription. In light of these data, we propose that MVI is important for nucleolar and ribosome maintenance but not for RNA polymerase 1-related transcription.
Collapse
Affiliation(s)
- Jolanta Nowak
- Laboratory of Molecular Basis of Cell Motility, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Robert Lenartowski
- Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Torun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University in Torun, Torun, Poland
| | - Katarzyna Kalita
- Laboratory of Neurobiology, Nencki-EMBL Partnership for Neural Plasticity and Brain Disorders—BRAINCITY, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Lilya Lehka
- Laboratory of Molecular Basis of Cell Motility, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Olena Karatsai
- Laboratory of Molecular Basis of Cell Motility, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Marta Lenartowska
- Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Torun, Poland
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University in Torun, Torun, Poland
| | - Maria Jolanta Rędowicz
- Laboratory of Molecular Basis of Cell Motility, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| |
Collapse
|
5
|
Wang F, Yu X, Qian J, Cao Y, Dong S, Zhan S, Lu Z, Bast RC, Song Q, Chen Y, Zhang Y, Zhou J. A novel SIK2 inhibitor SIC-19 exhibits synthetic lethality with PARP inhibitors in ovarian cancer. Drug Resist Updat 2024; 74:101077. [PMID: 38518726 DOI: 10.1016/j.drup.2024.101077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/28/2023] [Accepted: 02/29/2024] [Indexed: 03/24/2024]
Abstract
PURPOSE Ovarian cancer patients with HR proficiency (HRP) have had limited benefits from PARP inhibitor treatment, highlighting the need for improved therapeutic strategies. In this study, we developed a novel SIK2 inhibitor, SIC-19, and investigated its potential to enhance the sensitivity and expand the clinical utility of PARP inhibitors in ovarian cancer. METHODS The SIK2 protein was modeled using a Molecular Operating Environment (MOE), and the most favorable model was selected based on a GBVI/WSA dG scoring function. The Chembridge Compound Library was screened, and the top 20 candidate compounds were tested for their interaction with SIK2 and downstream substrates, AKT-pS473 and MYLK-pS343. SIC-19 emerged as the most promising drug candidate and was further evaluated using multiple assays. RESULTS SIC-19 exhibited selective and potent inhibition of SIK2, leading to its degradation through the ubiquitination pathway. The IC50 of SIC-19 correlated inversely with endogenous SIK2 expression in ovarian cancer cell lines. Treatment with SIC-19 significantly inhibited cancer cell growth and sensitized cells to PARP inhibitors in vitro, as well as in ovarian cancer organoids and xenograft models. Mechanistically, SIK2 knockdown and SIC-19 treatment reduced RAD50 phosphorylation at Ser635, prevented nuclear translocation of RAD50, disrupted nuclear filament assembly, and impaired DNA homologous recombination repair, ultimately inducing apoptosis. These findings highlight the crucial role of SIK2 in the DNA HR repair pathway and demonstrate the significant PARP inhibitor sensitization achieved by SIC-19 in ovarian cancer. CONCLUSIONS SIC-19, a novel SIK2 inhibitor, effectively inhibits tumor cell growth in ovarian cancer by interfering with RAD50-mediated DNA HR repair. Furthermore, SIC-19 enhances the efficacy of PARP inhibitors, providing a promising therapeutic strategy to improve outcomes for ovarian cancer patients.
Collapse
Affiliation(s)
- Fang Wang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Xuejiao Yu
- Department of Imaging Department, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jun Qian
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yumin Cao
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Shunli Dong
- Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Shenghua Zhan
- Department of Pathology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhen Lu
- Department of Experimental Therapeutics, University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | - Robert C Bast
- Department of Experimental Therapeutics, University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | - Qingxia Song
- Department of Obstetrics and Gynecology, Nanjing University of Chinese Medicine Affiliated Suzhou Hospital, Suzhou, China
| | - Youguo Chen
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, China.
| | - Yi Zhang
- Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China.
| | - Jinhua Zhou
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Soochow University, Suzhou, China.
| |
Collapse
|
6
|
Ryu T, Merigliano C, Chiolo I. Nup153 is not required for anchoring heterochromatic DSBs to the nuclear periphery. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001176. [PMID: 38737725 PMCID: PMC11087819 DOI: 10.17912/micropub.biology.001176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/20/2024] [Accepted: 04/26/2024] [Indexed: 05/14/2024]
Abstract
Pericentromeric heterochromatin mostly comprises repeated DNA sequences prone to ectopic recombination. In Drosophila cells, 'safe' homologous recombination repair requires relocalization of heterochromatic repair sites to the nuclear periphery before Rad51 recruitment and strand invasion. DSBs are anchored to the nuclear periphery through the Nup107/160 nucleoporin complex. Previous studies suggested that the nuclear pore 'basket' protein Nup153 could also mediate anchoring, but Nup153 RNAi depletion also affects Nup107 association with the pores, preventing a direct assessment of Nup153 role. Using a separation of function mutant, here we show that Nup153 is not required for anchoring heterochromatic DSBs to the nuclear periphery.
Collapse
Affiliation(s)
- Taehyun Ryu
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Chiara Merigliano
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, USA
| | - Irene Chiolo
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
7
|
Shokrollahi M, Stanic M, Hundal A, Chan JNY, Urman D, Jordan CA, Hakem A, Espin R, Hao J, Krishnan R, Maass PG, Dickson BC, Hande MP, Pujana MA, Hakem R, Mekhail K. DNA double-strand break-capturing nuclear envelope tubules drive DNA repair. Nat Struct Mol Biol 2024:10.1038/s41594-024-01286-7. [PMID: 38632359 DOI: 10.1038/s41594-024-01286-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Accepted: 03/25/2024] [Indexed: 04/19/2024]
Abstract
Current models suggest that DNA double-strand breaks (DSBs) can move to the nuclear periphery for repair. It is unclear to what extent human DSBs display such repositioning. Here we show that the human nuclear envelope localizes to DSBs in a manner depending on DNA damage response (DDR) kinases and cytoplasmic microtubules acetylated by α-tubulin acetyltransferase-1 (ATAT1). These factors collaborate with the linker of nucleoskeleton and cytoskeleton complex (LINC), nuclear pore complex (NPC) protein NUP153, nuclear lamina and kinesins KIF5B and KIF13B to generate DSB-capturing nuclear envelope tubules (dsbNETs). dsbNETs are partly supported by nuclear actin filaments and the circadian factor PER1 and reversed by kinesin KIFC3. Although dsbNETs promote repair and survival, they are also co-opted during poly(ADP-ribose) polymerase (PARP) inhibition to restrain BRCA1-deficient breast cancer cells and are hyper-induced in cells expressing the aging-linked lamin A mutant progerin. In summary, our results advance understanding of nuclear structure-function relationships, uncover a nuclear-cytoplasmic DDR and identify dsbNETs as critical factors in genome organization and stability.
Collapse
Affiliation(s)
- Mitra Shokrollahi
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Mia Stanic
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Anisha Hundal
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Princess Margaret Cancer Research Centre, University Health Network, Toronto, Ontario, Canada
| | - Janet N Y Chan
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Defne Urman
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Chris A Jordan
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Anne Hakem
- Princess Margaret Cancer Research Centre, University Health Network, Toronto, Ontario, Canada
| | - Roderic Espin
- ProCURE, Catalan Institute of Oncology, Oncobell, Bellvitge Institute for Biomedical Research (IDIBELL), L'Hospitalet del Llobregat, Barcelona, Spain
- Biomedical Research Network Centre in Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - Jun Hao
- Princess Margaret Cancer Research Centre, University Health Network, Toronto, Ontario, Canada
| | - Rehna Krishnan
- Princess Margaret Cancer Research Centre, University Health Network, Toronto, Ontario, Canada
| | - Philipp G Maass
- Department of Molecular Genetics, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Brendan C Dickson
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Manoor P Hande
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Miquel A Pujana
- ProCURE, Catalan Institute of Oncology, Oncobell, Bellvitge Institute for Biomedical Research (IDIBELL), L'Hospitalet del Llobregat, Barcelona, Spain
- Biomedical Research Network Centre in Respiratory Diseases (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - Razqallah Hakem
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
- Princess Margaret Cancer Research Centre, University Health Network, Toronto, Ontario, Canada.
- Department of Medical Biophysics, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
| | - Karim Mekhail
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
- Temerty Centre for AI Research and Education in Medicine, University of Toronto, Toronto, Ontario, Canada.
- College of New Scholars, Artists and Scientists, Royal Society of Canada, Ottawa, Ontario, Canada.
| |
Collapse
|
8
|
Roy S, Adhikary H, D’Amours D. The SMC5/6 complex: folding chromosomes back into shape when genomes take a break. Nucleic Acids Res 2024; 52:2112-2129. [PMID: 38375830 PMCID: PMC10954462 DOI: 10.1093/nar/gkae103] [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: 11/13/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/21/2024] Open
Abstract
High-level folding of chromatin is a key determinant of the shape and functional state of chromosomes. During cell division, structural maintenance of chromosome (SMC) complexes such as condensin and cohesin ensure large-scale folding of chromatin into visible chromosomes. In contrast, the SMC5/6 complex plays more local and context-specific roles in the structural organization of interphase chromosomes with important implications for health and disease. Recent advances in single-molecule biophysics and cryo-electron microscopy revealed key insights into the architecture of the SMC5/6 complex and how interactions connecting the complex to chromatin components give rise to its unique repertoire of interphase functions. In this review, we provide an integrative view of the features that differentiates the SMC5/6 complex from other SMC enzymes and how these enable dramatic reorganization of DNA folding in space during DNA repair reactions and other genome transactions. Finally, we explore the mechanistic basis for the dynamic targeting of the SMC5/6 complex to damaged chromatin and its crucial role in human health.
Collapse
Affiliation(s)
- Shamayita Roy
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Hemanta Adhikary
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| | - Damien D’Amours
- Ottawa Institute of Systems Biology, Department of Cellular and Molecular Medicine, University of Ottawa, Roger Guindon Hall, 451 Smyth Rd, Ottawa, ON K1H 8M5, Canada
| |
Collapse
|
9
|
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
|
10
|
Dai Y, Yu Y, Nie J, Gu K, Pei H. X-ray-downregulated nucleophosmin induces abnormal polarization by anchoring to G-actin. LIFE SCIENCES IN SPACE RESEARCH 2024; 40:81-88. [PMID: 38245352 DOI: 10.1016/j.lssr.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/02/2023] [Accepted: 09/04/2023] [Indexed: 01/22/2024]
Abstract
Ionizing radiation poses significant risks to astronauts during deep space exploration. This study investigates the impact of radiation on nucleophosmin (NPM), a protein involved in DNA repair, cell cycle regulation, and proliferation. Using X-rays, a common space radiation, we found that radiation suppresses NPM expression. Knockdown of NPM increases DNA damage after irradiation, disrupts cell cycle distribution and enhances cellular radiosensitivity. Additionally, NPM interacts with globular actin (G-actin), affecting its translocation and centrosome binding during mitosis. These findings provide insights into the role of NPM in cellular processes in responding to radiation. This article enhances our comprehension of radiation-induced genomic instability and provides a foundational platform for prospective investigations within the realm of space radiation and its implications for cancer therapy.
Collapse
Affiliation(s)
- Yingchu Dai
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Suzhou Medical College of Soochow University, Suzhou, 215123, China.
| | - Yongduo Yu
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Suzhou Medical College of Soochow University, Suzhou, 215123, China
| | - Jing Nie
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Suzhou Medical College of Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, 215123, China
| | - Ke Gu
- Department of Radiotherapy and Oncology, The Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Hailong Pei
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, Suzhou Medical College of Soochow University, Suzhou, 215123, China; Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, 215123, China.
| |
Collapse
|
11
|
Simon MN, Dubrana K, Palancade B. On the edge: how nuclear pore complexes rule genome stability. Curr Opin Genet Dev 2024; 84:102150. [PMID: 38215626 DOI: 10.1016/j.gde.2023.102150] [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: 09/01/2023] [Revised: 11/10/2023] [Accepted: 12/18/2023] [Indexed: 01/14/2024]
Abstract
Nuclear organization has emerged as a critical layer in the coordination of DNA repair activities. Distinct types of DNA lesions have notably been shown to relocate at the vicinity of nuclear pore complexes (NPCs), where specific repair pathways are favored, ultimately safeguarding genome integrity. Here, we review the most recent progress in this field, notably highlighting the increasingly diverse types of DNA structures undergoing repositioning, and the signaling pathways involved. We further discuss our growing knowledge of the molecular mechanisms underlying the choice of repair pathways at NPCs, and their conservation - or divergences. Intriguingly, a series of recent findings suggest that DNA metabolism may be coupled to NPC biogenesis and specialization, challenging our initial vision of these processes.
Collapse
Affiliation(s)
- Marie-Noëlle Simon
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Institut Paoli-Calmettes, Equipe Labélisée Ligue, Aix Marseille University, Marseille, France. https://twitter.com/@IJMonod
| | - Karine Dubrana
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, F-92260 Fontenay-aux-Roses, France; Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, F-92260 Fontenay-aux-Roses, France. https://twitter.com/@DubranaLab
| | - Benoit Palancade
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France.
| |
Collapse
|
12
|
Verma N, Renauer PA, Dong C, Xin S, Lin Q, Zhang F, Glazer PM, Chen S. Genome scale CRISPR screens identify actin capping proteins as key modulators of therapeutic responses to radiation and immunotherapy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.14.575614. [PMID: 38293095 PMCID: PMC10827061 DOI: 10.1101/2024.01.14.575614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Radiotherapy (RT), is a fundamental treatment for malignant tumors and is used in over half of cancer patients. As radiation can promote anti-tumor immune effects, a promising therapeutic strategy is to combine radiation with immune checkpoint inhibitors (ICIs). However, the genetic determinants that impact therapeutic response in the context of combination therapy with radiation and ICI have not been systematically investigated. To unbiasedly identify the tumor intrinsic genetic factors governing such responses, we perform a set of genome-scale CRISPR screens in melanoma cells for cancer survival in response to low-dose genotoxic radiation treatment, in the context of CD8 T cell co-culture and with anti-PD1 checkpoint blockade antibody. Two actin capping proteins, Capza3 and Capg, emerge as top hits that upon inactivation promote the survival of melanoma cells in such settings. Capza3 and Capg knockouts (KOs) in mouse and human cancer cells display persistent DNA damage due to impaired homology directed repair (HDR); along with increased radiation, chemotherapy, and DNA repair inhibitor sensitivity. However, when cancer cells with these genes inactivated were exposed to sublethal radiation, inactivation of such actin capping protein promotes activation of the STING pathway, induction of inhibitory CEACAM1 ligand expression and resistance to CD8 T cell killing. Patient cancer genomics analysis reveals an increased mutational burden in patients with inactivating mutations in CAPG and/or CAPZA3, at levels comparable to other HDR associated genes. There is also a positive correlation between CAPG expression and activation of immune related pathways and CD8 T cell tumor infiltration. Our results unveil the critical roles of actin binding proteins for efficient HDR within cancer cells and demonstrate a previously unrecognized regulatory mechanism of therapeutic response to radiation and immunotherapy.
Collapse
Affiliation(s)
- Nipun Verma
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
- Department of Therapeutic Radiology, Yale University, New Haven, Connecticut, USA
| | - Paul A. Renauer
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
| | - Chuanpeng Dong
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
| | - Shan Xin
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
| | - Qianqian Lin
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
| | - Feifei Zhang
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
| | - Peter M. Glazer
- Department of Therapeutic Radiology, Yale University, New Haven, Connecticut, USA
- Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Sidi Chen
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
- System Biology Institute, Yale University, West Haven, Connecticut, USA
- Immunobiology Program, Yale University, New Haven, Connecticut, USA
- Molecular Cell Biology, Genetics, and Development Program, Yale University, New Haven, Connecticut, USA
- Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, Connecticut, USA
- Yale Stem Cell Center, Yale University School of Medicine, New Haven, Connecticut, USA
- Yale Center for Biomedical Data Science, Yale University School of Medicine, New Haven, Connecticut, USA
| |
Collapse
|
13
|
van Bueren MAE, Janssen A. The impact of chromatin on double-strand break repair: Imaging tools and discoveries. DNA Repair (Amst) 2024; 133:103592. [PMID: 37976899 DOI: 10.1016/j.dnarep.2023.103592] [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: 07/27/2023] [Revised: 10/16/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
Eukaryotic nuclei are constantly being exposed to factors that break or chemically modify the DNA. Accurate repair of this DNA damage is crucial to prevent DNA mutations and maintain optimal cell function. To overcome the detrimental effects of DNA damage, a multitude of repair pathways has evolved. These pathways need to function properly within the different chromatin domains present in the nucleus. Each of these domains exhibit distinct molecular- and bio-physical characteristics that can influence the response to DNA damage. In particular, chromatin domains highly enriched for repetitive DNA sequences, such as nucleoli, centromeres and pericentromeric heterochromatin require tailored repair mechanisms to safeguard genome stability. Work from the past decades has led to the development of innovative imaging tools as well as inducible DNA damage techniques to gain new insights into the impact of these repetitive chromatin domains on the DNA repair process. Here we summarize these tools with a particular focus on Double-Strand Break (DSB) repair, and discuss the insights gained into our understanding of the influence of chromatin domains on DSB -dynamics and -repair pathway choice.
Collapse
Affiliation(s)
- Marit A E van Bueren
- Center for Molecular Medicine, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Aniek Janssen
- Center for Molecular Medicine, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands.
| |
Collapse
|
14
|
Wang T, Zheng AX, Li P, Tang T, Zhang LP, Hong Y, Hong X, Deng ZH. FAM21 interacts with Ku to promote the localization of WASH to DNA double strand break sites. DNA Repair (Amst) 2024; 133:103603. [PMID: 38029687 DOI: 10.1016/j.dnarep.2023.103603] [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: 05/15/2023] [Revised: 10/25/2023] [Accepted: 11/10/2023] [Indexed: 12/01/2023]
Abstract
Cytoplasmic FAM21 works as a guiding protein in Wiskott-Aldrich Syndrome Protein and SCAR Homolog (WASH) complex by linking WASH complex to endosomes through its interaction with retromer. Recently, we have reported that nuclear WASH localizes to DNA double strand break (DSB) sites to promote DNA repair through non-homologous end-joining (NHEJ). However, whether FAM21, the close partner of WASH, is involved in the nuclear WASH localization and DNA repair remains to be clarified. Here, we show that FAM21 interacts with Ku and the interaction between C-terminal FAM21 and Ku is essential for its recruitment to DSB sites. Moreover, FAM21 depletion led to decreases in WASH recruitment to damaged DNA and repair capacity upon DNA damage. Taken together, these results reveal that FAM21 promotes DNA repair by orchestrating the recruitment of WASH to DSB sites, providing a mechanistic insight into WASH-dependent DNA DSB repair.
Collapse
Affiliation(s)
- Tao Wang
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China.
| | - Ai-Xue Zheng
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
| | - Ping Li
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
| | - Tuo Tang
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
| | - Lu-Ping Zhang
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
| | - Yu Hong
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
| | - Xian Hong
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China
| | - Zhi-Hui Deng
- Laboratory of Protein Structure and Function, Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, China.
| |
Collapse
|
15
|
Spegg V, Altmeyer M. Genome maintenance meets mechanobiology. Chromosoma 2024; 133:15-36. [PMID: 37581649 PMCID: PMC10904543 DOI: 10.1007/s00412-023-00807-5] [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: 04/04/2023] [Revised: 06/20/2023] [Accepted: 07/26/2023] [Indexed: 08/16/2023]
Abstract
Genome stability is key for healthy cells in healthy organisms, and deregulated maintenance of genome integrity is a hallmark of aging and of age-associated diseases including cancer and neurodegeneration. To maintain a stable genome, genome surveillance and repair pathways are closely intertwined with cell cycle regulation and with DNA transactions that occur during transcription and DNA replication. Coordination of these processes across different time and length scales involves dynamic changes of chromatin topology, clustering of fragile genomic regions and repair factors into nuclear repair centers, mobilization of the nuclear cytoskeleton, and activation of cell cycle checkpoints. Here, we provide a general overview of cell cycle regulation and of the processes involved in genome duplication in human cells, followed by an introduction to replication stress and to the cellular responses elicited by perturbed DNA synthesis. We discuss fragile genomic regions that experience high levels of replication stress, with a particular focus on telomere fragility caused by replication stress at the ends of linear chromosomes. Using alternative lengthening of telomeres (ALT) in cancer cells and ALT-associated PML bodies (APBs) as examples of replication stress-associated clustered DNA damage, we discuss compartmentalization of DNA repair reactions and the role of protein properties implicated in phase separation. Finally, we highlight emerging connections between DNA repair and mechanobiology and discuss how biomolecular condensates, components of the nuclear cytoskeleton, and interfaces between membrane-bound organelles and membraneless macromolecular condensates may cooperate to coordinate genome maintenance in space and time.
Collapse
Affiliation(s)
- Vincent Spegg
- Department of Molecular Mechanisms of Disease, University of Zurich, Zurich, Switzerland
| | - Matthias Altmeyer
- Department of Molecular Mechanisms of Disease, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
16
|
González-Acosta D, Lopes M. DNA replication and replication stress response in the context of nuclear architecture. Chromosoma 2024; 133:57-75. [PMID: 38055079 PMCID: PMC10904558 DOI: 10.1007/s00412-023-00813-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/23/2023] [Accepted: 10/24/2023] [Indexed: 12/07/2023]
Abstract
The DNA replication process needs to be coordinated with other DNA metabolism transactions and must eventually extend to the full genome, regardless of chromatin status, gene expression, secondary structures and DNA lesions. Completeness and accuracy of DNA replication are crucial to maintain genome integrity, limiting transformation in normal cells and offering targeting opportunities for proliferating cancer cells. DNA replication is thus tightly coordinated with chromatin dynamics and 3D genome architecture, and we are only beginning to understand the underlying molecular mechanisms. While much has recently been discovered on how DNA replication initiation is organised and modulated in different genomic regions and nuclear territories-the so-called "DNA replication program"-we know much less on how the elongation of ongoing replication forks and particularly the response to replication obstacles is affected by the local nuclear organisation. Also, it is still elusive how specific components of nuclear architecture participate in the replication stress response. Here, we review known mechanisms and factors orchestrating replication initiation, and replication fork progression upon stress, focusing on recent evidence linking genome organisation and nuclear architecture with the cellular responses to replication interference, and highlighting open questions and future challenges to explore this exciting new avenue of research.
Collapse
Affiliation(s)
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
17
|
Xu R, Pan Z, Nakagawa T. Gross Chromosomal Rearrangement at Centromeres. Biomolecules 2023; 14:28. [PMID: 38254628 PMCID: PMC10813616 DOI: 10.3390/biom14010028] [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: 11/28/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 01/24/2024] Open
Abstract
Centromeres play essential roles in the faithful segregation of chromosomes. CENP-A, the centromere-specific histone H3 variant, and heterochromatin characterized by di- or tri-methylation of histone H3 9th lysine (H3K9) are the hallmarks of centromere chromatin. Contrary to the epigenetic marks, DNA sequences underlying the centromere region of chromosomes are not well conserved through evolution. However, centromeres consist of repetitive sequences in many eukaryotes, including animals, plants, and a subset of fungi, including fission yeast. Advances in long-read sequencing techniques have uncovered the complete sequence of human centromeres containing more than thousands of alpha satellite repeats and other types of repetitive sequences. Not only tandem but also inverted repeats are present at a centromere. DNA recombination between centromere repeats can result in gross chromosomal rearrangement (GCR), such as translocation and isochromosome formation. CENP-A chromatin and heterochromatin suppress the centromeric GCR. The key player of homologous recombination, Rad51, safeguards centromere integrity through conservative noncrossover recombination between centromere repeats. In contrast to Rad51-dependent recombination, Rad52-mediated single-strand annealing (SSA) and microhomology-mediated end-joining (MMEJ) lead to centromeric GCR. This review summarizes recent findings on the role of centromere and recombination proteins in maintaining centromere integrity and discusses how GCR occurs at centromeres.
Collapse
Affiliation(s)
- Ran Xu
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka, Japan
- Forefront Research Center, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka, Japan
| | - Ziyi Pan
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka, Japan
- Forefront Research Center, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka, Japan
| | - Takuro Nakagawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka, Japan
- Forefront Research Center, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Osaka, Japan
| |
Collapse
|
18
|
Stromberg KA, Spain T, Tomlin SA, Powell J, Amarillo KD, Schroeder CM. Evolutionary diversification reveals distinct somatic versus germline cytoskeletal functions of the Arp2 branched actin nucleator protein. Curr Biol 2023; 33:5326-5339.e7. [PMID: 37977138 PMCID: PMC10785674 DOI: 10.1016/j.cub.2023.10.055] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/18/2023] [Accepted: 10/25/2023] [Indexed: 11/19/2023]
Abstract
Branched actin networks are critical in many cellular processes, including cell motility and division. Arp2, a protein within the seven-membered Arp2/3 complex, is responsible for generating branched actin. Given its essential roles, Arp2 evolves under stringent sequence conservation throughout eukaryotic evolution. We unexpectedly discovered recurrent evolutionary diversification of Arp2 in Drosophila, yielding independently arising paralogs Arp2D in obscura species and Arp2D2 in montium species. Both paralogs are unusually testis-enriched in expression relative to Arp2. We investigated whether their sequence divergence from canonical Arp2 led to functional specialization by replacing Arp2 in D. melanogaster with either Arp2D or Arp2D2. Despite their divergence, we surprisingly found that both complement Arp2's essential function in somatic tissue, suggesting they have preserved the ability to polymerize branched actin even in a non-native species. However, we found that Arp2D- and Arp2D2-expressing males display defects throughout sperm development, with Arp2D resulting in more pronounced deficiencies and subfertility, suggesting the Arp2 paralogs are cross-species incompatible in the testis. We focused on Arp2D and pinpointed two highly diverged structural regions-the D-loop and C terminus-and found that they contribute to germline defects in D. melanogaster sperm development. However, while the Arp2D C terminus is suboptimal in the D. melanogaster testis, it is essential for Arp2D somatic function. Testis cytology of the paralogs' native species revealed striking differences in germline actin structures, indicating unique cytoskeletal requirements. Our findings suggest canonical Arp2 function differs between somatic versus germline contexts, and Arp2 paralogs may have recurrently evolved for species-specialized actin branching in the testis.
Collapse
Affiliation(s)
- Kaitlin A Stromberg
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Tristan Spain
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Sarah A Tomlin
- Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Fred Hutchinson Cancer Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA
| | - Jordan Powell
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Kristen Dominique Amarillo
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Courtney M Schroeder
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA.
| |
Collapse
|
19
|
Colding-Christensen CS, Kakulidis ES, Arroyo-Gomez J, Hendriks IA, Arkinson C, Fábián Z, Gambus A, Mailand N, Duxin JP, Nielsen ML. Profiling ubiquitin signalling with UBIMAX reveals DNA damage- and SCF β-Trcp1-dependent ubiquitylation of the actin-organizing protein Dbn1. Nat Commun 2023; 14:8293. [PMID: 38097601 PMCID: PMC10721886 DOI: 10.1038/s41467-023-43873-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 11/22/2023] [Indexed: 12/17/2023] Open
Abstract
Ubiquitin widely modifies proteins, thereby regulating most cellular functions. The complexity of ubiquitin signalling necessitates unbiased methods enabling global detection of dynamic protein ubiquitylation. Here, we describe UBIMAX (UBiquitin target Identification by Mass spectrometry in Xenopus egg extracts), which enriches ubiquitin-conjugated proteins and quantifies regulation of protein ubiquitylation under precise and adaptable conditions. We benchmark UBIMAX by investigating DNA double-strand break-responsive ubiquitylation events, identifying previously known targets and revealing the actin-organizing protein Dbn1 as a major target of DNA damage-induced ubiquitylation. We find that Dbn1 is targeted for proteasomal degradation by the SCFβ-Trcp1 ubiquitin ligase, in a conserved mechanism driven by ATM-mediated phosphorylation of a previously uncharacterized β-Trcp1 degron containing an SQ motif. We further show that this degron is sufficient to induce DNA damage-dependent protein degradation of a model substrate. Collectively, we demonstrate UBIMAX's ability to identify targets of stimulus-regulated ubiquitylation and reveal an SCFβ-Trcp1-mediated ubiquitylation mechanism controlled directly by the apical DNA damage response kinases.
Collapse
Affiliation(s)
- Camilla S Colding-Christensen
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Ellen S Kakulidis
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Javier Arroyo-Gomez
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Ivo A Hendriks
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Connor Arkinson
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- California Institute for Quantitative Biosciences and Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Zita Fábián
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Agnieszka Gambus
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Niels Mailand
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Julien P Duxin
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
| | - Michael L Nielsen
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.
| |
Collapse
|
20
|
Wernlé K, Thiel CS, Ullrich O. Increased H3K9me3 and F-Actin Reorganization in the Rapid Adaptive Response to Hypergravity in Human T Lymphocytes. Int J Mol Sci 2023; 24:17232. [PMID: 38139061 PMCID: PMC10743231 DOI: 10.3390/ijms242417232] [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: 10/31/2023] [Revised: 11/27/2023] [Accepted: 12/05/2023] [Indexed: 12/24/2023] Open
Abstract
Our study explored the impact of hypergravity on human T cells, which experience additional acceleration forces beyond Earth's gravity due to various factors, such as pulsatile blood flow, and technology, such as high-performance aircraft flights or spaceflights. We investigated the histone modifications Histone 3 lysine 4 and 9 trimethylation (H3K4me3 and H3K9me3, respectively), as well as the structural and cytoskeletal organization of Jurkat T cells in response to hypergravity. Histone modifications play a crucial role in gene regulation, chromatin organization and DNA repair. In response to hypergravity, we found only minimal changes of H3K4me3 and a rapid increase in H3K9me3, which was sustained for up to 15 min and then returned to control levels after 1 h. Furthermore, rapid changes in F-actin fluorescence were observed within seconds of hypergravity exposure, indicating filament depolymerization and cytoskeletal restructuring, which subsequently recovered after 1 h of hypergravity. Our study demonstrated the rapid, dynamic and adaptive cellular response to hypergravity, particularly in terms of histone modifications and cytoskeletal changes. These responses are likely necessary for maintaining genome stability and structural integrity under hypergravity conditions as they are constantly occurring in the human body during blood cell circulation.
Collapse
Affiliation(s)
- Kendra Wernlé
- Institute of Anatomy, Faculty of Medicine, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland;
- Faculty of Medical Sciences, Private University of the Principality of Liechtenstein (UFL), Dorfstrasse 24, 9495 Triesen, Liechtenstein
| | - Cora S. Thiel
- Institute of Anatomy, Faculty of Medicine, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland;
- Institute of Machine Design, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany
- Space Life Sciences Laboratory (SLSL), Kennedy Space Center, 505 Odyssey Way, Exploration Park, Merritt Island, FL 32953, USA
- UZH Space Hub, Air Force Center, Air Base Dübendorf, Überlandstrasse 270, 8600 Dubendorf, Switzerland
| | - Oliver Ullrich
- Institute of Anatomy, Faculty of Medicine, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland;
- Institute of Machine Design, Otto-von-Guericke-University Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany
- Space Life Sciences Laboratory (SLSL), Kennedy Space Center, 505 Odyssey Way, Exploration Park, Merritt Island, FL 32953, USA
- UZH Space Hub, Air Force Center, Air Base Dübendorf, Überlandstrasse 270, 8600 Dubendorf, Switzerland
- Department of Industrial Engineering, Ernst-Abbe-Hochschule (EAH) Jena, Carl-Zeiss-Promenade 2, 07745 Jena, Germany
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| |
Collapse
|
21
|
Palumbieri MD, Merigliano C, González-Acosta D, Kuster D, Krietsch J, Stoy H, von Känel T, Ulferts S, Welter B, Frey J, Doerdelmann C, Sanchi A, Grosse R, Chiolo I, Lopes M. Nuclear actin polymerization rapidly mediates replication fork remodeling upon stress by limiting PrimPol activity. Nat Commun 2023; 14:7819. [PMID: 38016948 PMCID: PMC10684888 DOI: 10.1038/s41467-023-43183-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 11/02/2023] [Indexed: 11/30/2023] Open
Abstract
Cells rapidly respond to replication stress actively slowing fork progression and inducing fork reversal. How replication fork plasticity is achieved in the context of nuclear organization is currently unknown. Using nuclear actin probes in living and fixed cells, we visualized nuclear actin filaments in unperturbed S phase and observed their rapid extension in number and length upon genotoxic treatments, frequently taking contact with replication factories. Chemically or genetically impairing nuclear actin polymerization shortly before these treatments prevents active fork slowing and abolishes fork reversal. Defective fork remodeling is linked to deregulated chromatin loading of PrimPol, which promotes unrestrained and discontinuous DNA synthesis and limits the recruitment of RAD51 and SMARCAL1 to nascent DNA. Moreover, defective nuclear actin polymerization upon mild replication interference induces chromosomal instability in a PRIMPOL-dependent manner. Hence, by limiting PrimPol activity, nuclear F-actin orchestrates replication fork plasticity and is a key molecular determinant in the rapid cellular response to genotoxic treatments.
Collapse
Affiliation(s)
| | - Chiara Merigliano
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, USA
| | | | - Danina Kuster
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Jana Krietsch
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Henriette Stoy
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
- Department of Cellular and Molecular Medicine, Copenhagen University, Copenhagen, Denmark
| | - Thomas von Känel
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Svenja Ulferts
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty, University of Freiburg, Freiburg im Breisgau, Germany
| | - Bettina Welter
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Joël Frey
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Cyril Doerdelmann
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Andrea Sanchi
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Robert Grosse
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty, University of Freiburg, Freiburg im Breisgau, Germany
- CIBSS - Centre for Integrative Biological Signaling Studies, University of Freiburg, Freiburg im Breisgau, Germany
| | - Irene Chiolo
- Molecular and Computational Biology Department, University of Southern California, Los Angeles, CA, USA.
| | - Massimo Lopes
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
22
|
Stanczyk P, Tatekoshi Y, Shapiro JS, Nayudu K, Chen Y, Zilber Z, Schipma M, De Jesus A, Mahmoodzadeh A, Akrami A, Chang HC, Ardehali H. DNA Damage and Nuclear Morphological Changes in Cardiac Hypertrophy Are Mediated by SNRK Through Actin Depolymerization. Circulation 2023; 148:1582-1592. [PMID: 37721051 PMCID: PMC10840668 DOI: 10.1161/circulationaha.123.066002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/23/2023] [Indexed: 09/19/2023]
Abstract
BACKGROUND Proper nuclear organization is critical for cardiomyocyte function, because global structural remodeling of nuclear morphology and chromatin structure underpins the development and progression of cardiovascular disease. Previous reports have implicated a role for DNA damage in cardiac hypertrophy; however, the mechanism for this process is not well delineated. AMPK (AMP-activated protein kinase) family of proteins regulates metabolism and DNA damage response (DDR). Here, we examine whether a member of this family, SNRK (SNF1-related kinase), which plays a role in cardiac metabolism, is also involved in hypertrophic remodeling through changes in DDR and structural properties of the nucleus. METHODS We subjected cardiac-specific Snrk-/- mice to transaortic banding to assess the effect on cardiac function and DDR. In parallel, we modulated SNRK in vitro and assessed its effects on DDR and nuclear parameters. We also used phosphoproteomics to identify novel proteins that are phosphorylated by SNRK. Last, coimmunoprecipitation was used to verify Destrin (DSTN) as the binding partner of SNRK that modulates its effects on the nucleus and DDR. RESULTS Cardiac-specific Snrk-/- mice display worse cardiac function and cardiac hypertrophy in response to transaortic banding, and an increase in DDR marker pH2AX (phospho-histone 2AX) in their hearts. In addition, in vitro Snrk knockdown results in increased DNA damage and chromatin compaction, along with alterations in nuclear flatness and 3-dimensional volume. Phosphoproteomic studies identified a novel SNRK target, DSTN, a member of F-actin depolymerizing factor proteins that directly bind to and depolymerize F-actin. SNRK binds to DSTN, and DSTN downregulation reverses excess DNA damage and changes in nuclear parameters, in addition to cellular hypertrophy, with SNRK knockdown. We also demonstrate that SNRK knockdown promotes excessive actin depolymerization, measured by the increased ratio of G-actin to F-actin. Last, jasplakinolide, a pharmacological stabilizer of F-actin, rescues the increased DNA damage and aberrant nuclear morphology in SNRK-downregulated cells. CONCLUSIONS These results indicate that SNRK is a key player in cardiac hypertrophy and DNA damage through its interaction with DSTN. This interaction fine-tunes actin polymerization to reduce DDR and maintain proper cardiomyocyte nuclear shape and morphology.
Collapse
Affiliation(s)
- Paulina Stanczyk
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- These authors contributed equally
| | - Yuki Tatekoshi
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
- These authors contributed equally
| | - Jason S. Shapiro
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
- These authors contributed equally
| | - Krithika Nayudu
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Yihan Chen
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Zachary Zilber
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Matthew Schipma
- Department of Biochemistry and Molecular Genetics, Northwestern University School of Medicine, Chicago, IL, USA
| | - Adam De Jesus
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Amir Mahmoodzadeh
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Ashley Akrami
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Hsiang-Chun Chang
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Hossein Ardehali
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| |
Collapse
|
23
|
Wollscheid HP, Ulrich HD. Chromatin meets the cytoskeleton: the importance of nuclear actin dynamics and associated motors for genome stability. DNA Repair (Amst) 2023; 131:103571. [PMID: 37738698 DOI: 10.1016/j.dnarep.2023.103571] [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: 05/09/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023]
Abstract
The actin cytoskeleton is of fundamental importance for numerous cellular processes, including intracellular transport, cell plasticity, and cell migration. However, functions of filamentous actin (F-actin) in the nucleus remain understudied due to the comparatively low abundance of nuclear actin and the resulting experimental limitations to its visualization. Owing to recent technological advances such as super-resolution microscopy and the development of nuclear-specific actin probes, essential roles of the actin cytoskeleton in the context of genome maintenance are now emerging. In addition to the contributions of monomeric actin as a component of multiple important nuclear protein complexes, nuclear actin has been found to undergo polymerization in response to DNA damage and DNA replication stress. Consequently, nuclear F-actin plays important roles in the regulation of intra-nuclear mobility of repair and replication foci as well as the maintenance of nuclear shape, two important aspects of efficient stress tolerance. Beyond actin itself, there is accumulating evidence for the participation of multiple actin-binding proteins (ABPs) in the surveillance of genome integrity, including nucleation factors and motor proteins of the myosin family. Here we summarize recent findings highlighting the importance of actin cytoskeletal factors within the nucleus in key genome maintenance pathways.
Collapse
Affiliation(s)
- Hans-Peter Wollscheid
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, Mainz D - 55128, Germany.
| | - Helle D Ulrich
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, Mainz D - 55128, Germany.
| |
Collapse
|
24
|
Liu Y, Yao X, Zhao Y, Fang D, Shi L, Yang L, Song G, Cai K, Li L, Deng Q, Li M, Luo Z. Mechanotransduction in response to ECM stiffening impairs cGAS immune signaling in tumor cells. Cell Rep 2023; 42:113213. [PMID: 37804510 DOI: 10.1016/j.celrep.2023.113213] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 08/07/2023] [Accepted: 09/19/2023] [Indexed: 10/09/2023] Open
Abstract
The tumor microenvironment (TME) plays decisive roles in disabling T cell-mediated antitumor immunity, but the immunoregulatory functions of its biophysical properties remain elusive. Extracellular matrix (ECM) stiffening is a hallmark of solid tumors. Here, we report that the stiffened ECM contributes to the immunosuppression in TME via activating the Rho-associated coiled-coil-containing protein kinase (ROCK)-myosin IIA-filamentous actin (F-actin) mechanosignaling pathway in tumor cells to promote the generation of TRIM14-scavenging nonmuscle myosin heavy chain IIA (NMHC-IIA)-F-actin stress fibers, thus accelerating the autophagic degradation of cyclic guanosine monophosphate (GMP)-AMP synthase (cGAS) to deprive tumor cyclic GMP-AMP (cGAMP) and further attenuating tumor immunogenicity. Pharmacological inhibition of myosin IIA effector molecules with blebbistatin (BLEB) or the RhoA upstream regulator of this pathway with simvastatin (SIM) restored tumor-intrinsic cGAS-mediated cGAMP production and enhanced antitumor immunity. Our work identifies that ECM stiffness is an important biophysical cue to regulate tumor immunogenicity via the ROCK-myosin IIA-F-actin axis and that inhibiting this mechanosignaling pathway could boost immunotherapeutic efficacy for effective solid tumor treatment.
Collapse
Affiliation(s)
- Yingqi Liu
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China
| | - Xuemei Yao
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China
| | - Youbo Zhao
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China
| | - De Fang
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China
| | - Lei Shi
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China
| | - Li Yang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing University, Chongqing 400044, P.R. China
| | - Guanbin Song
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing University, Chongqing 400044, P.R. China
| | - Kaiyong Cai
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing University, Chongqing 400044, P.R. China
| | - Liqi Li
- Department of General Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, P.R. China
| | - Qin Deng
- Analytical and Testing Center, Chongqing University, Chongqing 400044, P.R. China
| | - Menghuan Li
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China.
| | - Zhong Luo
- School of Life Science, Chongqing University, Chongqing 400044, P.R. China; 111 Project Laboratory of Biomechanics and Tissue Repair, College of Bioengineering, Chongqing University, Chongqing 400044, P.R. China.
| |
Collapse
|
25
|
Yuan G, Gao H, Yang T. Exploring the Role of the Plant Actin Cytoskeleton: From Signaling to Cellular Functions. Int J Mol Sci 2023; 24:15480. [PMID: 37895158 PMCID: PMC10607326 DOI: 10.3390/ijms242015480] [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: 08/29/2023] [Revised: 10/06/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023] Open
Abstract
The plant actin cytoskeleton is characterized by the basic properties of dynamic array, which plays a central role in numerous conserved processes that are required for diverse cellular functions. Here, we focus on how actins and actin-related proteins (ARPs), which represent two classical branches of a greatly diverse superfamily of ATPases, are involved in fundamental functions underlying signal regulation of plant growth and development. Moreover, we review the structure, assembly dynamics, and biological functions of filamentous actin (F-actin) from a molecular perspective. The various accessory proteins known as actin-binding proteins (ABPs) partner with F-actin to finely tune actin dynamics, often in response to various cell signaling pathways. Our understanding of the significance of the actin cytoskeleton in vital cellular activities has been furthered by comparison of conserved functions of actin filaments across different species combined with advanced microscopic techniques and experimental methods. We discuss the current model of the plant actin cytoskeleton, followed by examples of the signaling mechanisms under the supervision of F-actin related to cell morphogenesis, polar growth, and cytoplasmic streaming. Determination of the theoretical basis of how the cytoskeleton works is important in itself and is beneficial to future applications aimed at improving crop biomass and production efficiency.
Collapse
Affiliation(s)
| | | | - Tao Yang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China; (G.Y.); (H.G.)
| |
Collapse
|
26
|
Kovacs MT, Vallette M, Wiertsema P, Dingli F, Loew D, Nader GPDF, Piel M, Ceccaldi R. DNA damage induces nuclear envelope rupture through ATR-mediated phosphorylation of lamin A/C. Mol Cell 2023; 83:3659-3668.e10. [PMID: 37832547 PMCID: PMC10597398 DOI: 10.1016/j.molcel.2023.09.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 08/01/2023] [Accepted: 09/20/2023] [Indexed: 10/15/2023]
Abstract
The integrity of the nuclear envelope (NE) is essential for maintaining the structural stability of the nucleus. Rupture of the NE has been frequently observed in cancer cells, especially in the context of mechanical challenges, such as physical confinement and migration. However, spontaneous NE rupture events, without any obvious physical challenges to the cell, have also been described. The molecular mechanism(s) of these spontaneous NE rupture events remain to be explored. Here, we show that DNA damage and subsequent ATR activation leads to NE rupture. Upon DNA damage, lamin A/C is phosphorylated in an ATR-dependent manner, leading to changes in lamina assembly and, ultimately, NE rupture. In addition, we show that cancer cells with intrinsic DNA repair defects undergo frequent events of DNA-damage-induced NE rupture, which renders them extremely sensitive to further NE perturbations. Exploiting this NE vulnerability could provide a new angle to complement traditional, DNA-damage-based chemotherapy.
Collapse
Affiliation(s)
| | - Marie Vallette
- Inserm U830, PSL Research University, Institut Curie, 75005 Paris, France
| | - Pauline Wiertsema
- Inserm U830, PSL Research University, Institut Curie, 75005 Paris, France
| | - Florent Dingli
- Institut Curie, PSL Research University, Centre de Recherche, CurieCoreTech Spectrométrie de Masse Protéomique, 26 rue d'Ulm, Paris 75248 Cedex 05, France
| | - Damarys Loew
- Institut Curie, PSL Research University, Centre de Recherche, CurieCoreTech Spectrométrie de Masse Protéomique, 26 rue d'Ulm, Paris 75248 Cedex 05, France
| | | | - Matthieu Piel
- Institut Curie and Institut Pierre Gilles de Gennes, PSL Research University, CNRS, UMR 144, Paris, France
| | - Raphael Ceccaldi
- Inserm U830, PSL Research University, Institut Curie, 75005 Paris, France.
| |
Collapse
|
27
|
Du WW, Qadir J, Du KY, Chen Y, Wu N, Yang BB. Nuclear Actin Polymerization Regulates Cell Epithelial-Mesenchymal Transition. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2300425. [PMID: 37566765 PMCID: PMC10558697 DOI: 10.1002/advs.202300425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 06/28/2023] [Indexed: 08/13/2023]
Abstract
Current studies on actin function primarily rely on cytoplasmic actin due to the absence of cellular models specifically expressing nuclear actin. Here, cell models capable of expressing varying levels of nuclear F/G-actin are generated and a significant role of nuclear actin in the regulation of epithelial-mesenchymal transition (EMT) is uncovered. Through immunoprecipitation and mass spectrometry analyses, distinct binding partners for nuclear F-actin (β-catenin, SMAD2, and SMAD3) and nuclear G-actin (MYBBP1A, NKRF, and MYPOP) are investigated, which respectively modulate EMT-promoting and EMT-repressing transcriptional events. While nuclear F-actin promotes EMT with enhanced cell migration, survival, and elongated mesenchymal morphology, nuclear G-actin represses EMT and related cell activities. Mechanistically, nuclear F-actin enhances β-catenin, SMAD2, and SMAD3 expression and stability in the nuclei, while nuclear G-actin increases MYBBP1A, NKRF, and MYPOP expression and stability in the nuclei. The association between nuclear F/G-actin and N-cadherin/E-cadherin in the cell lines (in vitro), and increased nuclear actin polymerization in the wound healing cells (in vivo) affirm a significant role of nuclear actin in EMT regulation. With evidence of nuclear actin polymerization and EMT during development, and irregularities in disease states such as cancer and fibrosis, targeting nuclear actin dynamics to trigger dysregulated EMT warrants ongoing study.
Collapse
Affiliation(s)
- William W. Du
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Javeria Qadir
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Kevin Y. Du
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Yu Chen
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Nan Wu
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| | - Burton B. Yang
- Sunnybrook Research Instituteand Department of Laboratory Medicine and PathobiologyUniversity of TorontoTorontoONM4N3M5Canada
| |
Collapse
|
28
|
Nobari P, Doye V, Boumendil C. Metazoan nuclear pore complexes in gene regulation and genome stability. DNA Repair (Amst) 2023; 130:103565. [PMID: 37696111 DOI: 10.1016/j.dnarep.2023.103565] [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: 05/11/2023] [Revised: 08/28/2023] [Accepted: 08/28/2023] [Indexed: 09/13/2023]
Abstract
The nuclear pore complexes (NPCs), one of the hallmarks of eukaryotic nuclei, allow selective transport of macromolecules between the cytoplasm and the nucleus. Besides this canonical function, an increasing number of additional roles have been attributed to the NPCs and their constituents, the nucleoporins. Here we review recent insights into the mechanisms by which NPCs and nucleoporins affect transcription and DNA repair in metazoans. In the first part, we discuss how gene expression can be affected by the localization of genome-nucleoporin interactions at pores or "off-pores", by the role of nucleoporins in chromatin organization at different scales, or by the physical properties of nucleoporins. In the second part, we review the contribution of NPCs to genome stability, including transport-dependent and -independent functions and the role of positioning at NPCs in the repair of heterochromatic breaks and the regulation of replication stress.
Collapse
Affiliation(s)
- Parisa Nobari
- IGH, Université de Montpellier, CNRS, Montpellier, France
| | - Valérie Doye
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
| | | |
Collapse
|
29
|
Miller JM, Prange S, Ji H, Rau AR, Khodaverdian VY, Li X, Patel A, Butova N, Lutter A, Chung H, Merigliano C, Rawal CC, Hanscom T, McVey M, Chiolo I. Alternative end-joining results in smaller deletions in heterochromatin relative to euchromatin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.03.531058. [PMID: 37645729 PMCID: PMC10461932 DOI: 10.1101/2023.03.03.531058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Pericentromeric heterochromatin is highly enriched for repetitive sequences prone to aberrant recombination. Previous studies showed that homologous recombination (HR) repair is uniquely regulated in this domain to enable 'safe' repair while preventing aberrant recombination. In Drosophila cells, DNA double-strand breaks (DSBs) relocalize to the nuclear periphery through nuclear actin-driven directed motions before recruiting the strand invasion protein Rad51 and completing HR repair. End-joining (EJ) repair also occurs with high frequency in heterochromatin of fly tissues, but how alternative EJ (alt-EJ) pathways operate in heterochromatin remains largely uncharacterized. Here, we induce DSBs in single euchromatic and heterochromatic sites using a new system that combines the DR- white reporter and I-SceI expression in spermatogonia of flies. Using this approach, we detect higher frequency of HR repair in heterochromatin, relative to euchromatin. Further, sequencing of mutagenic repair junctions reveals the preferential use of different EJ pathways across distinct euchromatic and heterochromatic sites. Interestingly, synthesis-dependent microhomology-mediated end joining (SD-MMEJ) appears differentially regulated in the two domains, with a preferential use of motifs close to the cut site in heterochromatin relative to euchromatin, resulting in smaller deletions. Together, these studies establish a new approach to study repair outcomes in fly tissues, and support the conclusion that heterochromatin uses more HR and less mutagenic EJ repair relative to euchromatin.
Collapse
|
30
|
Min J, Zhao J, Zagelbaum J, Lee J, Takahashi S, Cummings P, Schooley A, Dekker J, Gottesman ME, Rabadan R, Gautier J. Mechanisms of insertions at a DNA double-strand break. Mol Cell 2023; 83:2434-2448.e7. [PMID: 37402370 PMCID: PMC10527084 DOI: 10.1016/j.molcel.2023.06.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 04/06/2023] [Accepted: 06/08/2023] [Indexed: 07/06/2023]
Abstract
Insertions and deletions (indels) are common sources of structural variation, and insertions originating from spontaneous DNA lesions are frequent in cancer. We developed a highly sensitive assay called insertion and deletion sequencing (Indel-seq) to monitor rearrangements in human cells at the TRIM37 acceptor locus that reports indels stemming from experimentally induced and spontaneous genome instability. Templated insertions, which derive from sequences genome wide, require contact between donor and acceptor loci, require homologous recombination, and are stimulated by DNA end-processing. Insertions are facilitated by transcription and involve a DNA/RNA hybrid intermediate. Indel-seq reveals that insertions are generated via multiple pathways. The broken acceptor site anneals with a resected DNA break or invades the displaced strand of a transcription bubble or R-loop, followed by DNA synthesis, displacement, and then ligation by non-homologous end joining. Our studies identify transcription-coupled insertions as a critical source of spontaneous genome instability that is distinct from cut-and-paste events.
Collapse
Affiliation(s)
- Jaewon Min
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Herbert Irving Comprehensive Cancer Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
| | - Junfei Zhao
- Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jennifer Zagelbaum
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jina Lee
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Sho Takahashi
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Portia Cummings
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Allana Schooley
- Department of Systems Biology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Job Dekker
- Department of Systems Biology, University of Massachusetts Medical School, Worcester, MA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Max E Gottesman
- Department of Biochemistry and Biophysics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Raul Rabadan
- Herbert Irving Comprehensive Cancer Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Department of Systems Biology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jean Gautier
- Institute for Cancer Genetics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Herbert Irving Comprehensive Cancer Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA; Department of Genetics and Development, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
| |
Collapse
|
31
|
Stanczyk P, Tatekoshi Y, Shapiro JS, Nayudu K, Chen Y, Zilber Z, Schipma M, De Jesus A, Mahmoodzadeh A, Akrami A, Chang HC, Ardehali H. DNA damage and nuclear morphological changes in cardiac hypertrophy are mediated by SNRK through actin depolymerization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.14.549060. [PMID: 37503243 PMCID: PMC10370003 DOI: 10.1101/2023.07.14.549060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
BACKGROUND Proper nuclear organization is critical for cardiomyocyte (CM) function, as global structural remodeling of nuclear morphology and chromatin structure underpins the development and progression of cardiovascular disease. Previous reports have implicated a role for DNA damage in cardiac hypertrophy, however, the mechanism for this process is not well delineated. AMPK family of proteins regulate metabolism and DNA damage response (DDR). Here, we examine whether a member of this family, SNF1-related kinase (SNRK), which plays a role in cardiac metabolism, is also involved in hypertrophic remodeling through changes in DDR and structural properties of the nucleus. METHODS We subjected cardiac specific (cs)- Snrk -/- mice to trans-aortic banding (TAC) to assess the effect on cardiac function and DDR. In parallel, we modulated SNRK in vitro and assessed its effects on DDR and nuclear parameters. We also used phospho-proteomics to identify novel proteins that are phosphorylated by SNRK. Finally, co-immunoprecipitation (co-IP) was used to verify Destrin (DSTN) as the binding partner of SNRK that modulates its effects on the nucleus and DDR. RESULTS cs- Snrk -/- mice display worse cardiac function and cardiac hypertrophy in response to TAC, and an increase in DDR marker pH2AX in their hearts. Additionally, in vitro Snrk knockdown results in increased DNA damage and chromatin compaction, along with alterations in nuclear flatness and 3D volume. Phospho-proteomic studies identified a novel SNRK target, DSTN, a member of F-actin depolymerizing factor (ADF) proteins that directly binds to and depolymerize F-actin. SNRK binds to DSTN, and DSTN downregulation reverses excess DNA damage and changes in nuclear parameters, in addition to cellular hypertrophy, with SNRK knockdown. We also demonstrate that SNRK knockdown promotes excessive actin depolymerization, measured by the increased ratio of globular (G-) actin to F-actin. Finally, Jasplakinolide, a pharmacological stabilizer of F-actin, rescues the increased DNA damage and aberrant nuclear morphology in SNRK downregulated cells. CONCLUSIONS These results indicate that SNRK is a key player in cardiac hypertrophy and DNA damage through its interaction with DSTN. This interaction fine-tunes actin polymerization to reduce DDR and maintain proper CM nuclear shape and morphology. Clinical Perspective What is new? Animal hearts subjected to pressure overload display increased SNF1-related kinase (SNRK) protein expression levels and cardiomyocyte specific SNRK deletion leads to aggravated myocardial hypertrophy and heart failure.We have found that downregulation of SNRK impairs DSTN-mediated actin polymerization, leading to maladaptive changes in nuclear morphology, higher DNA damage response (DDR) and increased hypertrophy. What are the clinical implications? Our results suggest that disruption of DDR through genetic loss of SNRK results in an exaggerated pressure overload-induced cardiomyocyte hypertrophy.Targeting DDR, actin polymerization or SNRK/DSTN interaction represent promising therapeutic targets in pressure overload cardiac hypertrophy.
Collapse
Affiliation(s)
- Paulina Stanczyk
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- These authors contributed equally
| | - Yuki Tatekoshi
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
- These authors contributed equally
| | - Jason S. Shapiro
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
- These authors contributed equally
| | - Krithika Nayudu
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Yihan Chen
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Zachary Zilber
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Matthew Schipma
- Department of Biochemistry and Molecular Genetics, Northwestern University School of Medicine, Chicago, IL, USA
| | - Adam De Jesus
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Amir Mahmoodzadeh
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Ashley Akrami
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Hsiang-Chun Chang
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| | - Hossein Ardehali
- Division of Cardiology, Department of Medicine, and Feinberg Cardiovascular and Renal Research Institute, Northwestern University School of Medicine, Chicago, IL, USA
| |
Collapse
|
32
|
Nieminuszczy J, Martin PR, Broderick R, Krwawicz J, Kanellou A, Mocanu C, Bousgouni V, Smith C, Wen KK, Woodward B, Bakal C, Shackley F, Aguilera A, Stewart G, Vyas Y, Niedzwiedz W. Actin nucleators safeguard replication forks by limiting nascent strand degradation. Nucleic Acids Res 2023; 51:6337-6354. [PMID: 37224534 PMCID: PMC10325910 DOI: 10.1093/nar/gkad369] [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: 10/13/2022] [Revised: 04/17/2023] [Accepted: 05/11/2023] [Indexed: 05/26/2023] Open
Abstract
Accurate genome replication is essential for all life and a key mechanism of disease prevention, underpinned by the ability of cells to respond to replicative stress (RS) and protect replication forks. These responses rely on the formation of Replication Protein A (RPA)-single stranded (ss) DNA complexes, yet this process remains largely uncharacterized. Here, we establish that actin nucleation-promoting factors (NPFs) associate with replication forks, promote efficient DNA replication and facilitate association of RPA with ssDNA at sites of RS. Accordingly, their loss leads to deprotection of ssDNA at perturbed forks, impaired ATR activation, global replication defects and fork collapse. Supplying an excess of RPA restores RPA foci formation and fork protection, suggesting a chaperoning role for actin nucleators (ANs) (i.e. Arp2/3, DIAPH1) and NPFs (i.e, WASp, N-WASp) in regulating RPA availability upon RS. We also discover that β-actin interacts with RPA directly in vitro, and in vivo a hyper-depolymerizing β-actin mutant displays a heightened association with RPA and the same dysfunctional replication phenotypes as loss of ANs/NPFs, which contrasts with the phenotype of a hyper-polymerizing β-actin mutant. Thus, we identify components of actin polymerization pathways that are essential for preventing ectopic nucleolytic degradation of perturbed forks by modulating RPA activity.
Collapse
Affiliation(s)
- Jadwiga Nieminuszczy
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Peter R Martin
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Ronan Broderick
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Joanna Krwawicz
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Alexandra Kanellou
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Camelia Mocanu
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Vicky Bousgouni
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Charlotte Smith
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Kuo-Kuang Wen
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, Penn State College of Medicine, Penn State Health Children's Hospital, Hershey, PA 17033, USA
| | - Beth L Woodward
- Genome Stability and Human Disease Laboratory, Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Chris Bakal
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| | - Fiona Shackley
- Paediatric Immunology, Allergy and Infectious Diseases, Sheffield Children's Hospital NHS Foundation Trust, Sheffield, UK
| | - Andrés Aguilera
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Seville, Spain
| | - Grant S Stewart
- Genome Stability and Human Disease Laboratory, Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Yatin M Vyas
- Department of Pediatrics, Division of Pediatric Hematology-Oncology, Penn State College of Medicine, Penn State Health Children's Hospital, Hershey, PA 17033, USA
| | - Wojciech Niedzwiedz
- Division of Cancer Biology, The Institute of Cancer Research, London SW3 6JB, UK
| |
Collapse
|
33
|
Bailey MLP, Surovtsev I, Williams JF, Yan H, Yuan T, Li K, Duseau K, Mochrie SGJ, King MC. Loops and the activity of loop extrusion factors constrain chromatin dynamics. Mol Biol Cell 2023; 34:ar78. [PMID: 37126401 PMCID: PMC10398873 DOI: 10.1091/mbc.e23-04-0119] [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: 04/05/2023] [Revised: 04/19/2023] [Accepted: 04/20/2023] [Indexed: 05/02/2023] Open
Abstract
The chromosomes-DNA polymers and their binding proteins-are compacted into a spatially organized, yet dynamic, three-dimensional structure. Recent genome-wide chromatin conformation capture experiments reveal a hierarchical organization of the DNA structure that is imposed, at least in part, by looping interactions arising from the activity of loop extrusion factors. The dynamics of chromatin reflects the response of the polymer to a combination of thermal fluctuations and active processes. However, how chromosome structure and enzymes acting on chromatin together define its dynamics remains poorly understood. To gain insight into the structure-dynamics relationship of chromatin, we combine high-precision microscopy in living Schizosaccharomyces pombe cells with systematic genetic perturbations and Rouse model polymer simulations. We first investigated how the activity of two loop extrusion factors, the cohesin and condensin complexes, influences chromatin dynamics. We observed that deactivating cohesin, or to a lesser extent condensin, increased chromatin mobility, suggesting that loop extrusion constrains rather than agitates chromatin motion. Our corresponding simulations reveal that the introduction of loops is sufficient to explain the constraining activity of loop extrusion factors, highlighting that the conformation adopted by the polymer plays a key role in defining its dynamics. Moreover, we find that the number of loops or residence times of loop extrusion factors influence the dynamic behavior of the chromatin polymer. Last, we observe that the activity of the INO80 chromatin remodeler, but not the SWI/SNF or RSC complexes, is critical for ATP-dependent chromatin mobility in fission yeast. Taking the data together, we suggest that thermal and INO80-dependent activities exert forces that drive chromatin fluctuations, which are constrained by the organization of the chromosome into loops.
Collapse
Affiliation(s)
- Mary Lou P. Bailey
- Department of Applied Physics, Yale University, New Haven, CT 06511
- Integrated Graduate Program in Physics Engineering Biology, Yale University, New Haven, CT 06511
| | - Ivan Surovtsev
- Department of Physics, Yale University, New Haven, CT 06511
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | | | - Hao Yan
- Integrated Graduate Program in Physics Engineering Biology, Yale University, New Haven, CT 06511
- Department of Physics, Yale University, New Haven, CT 06511
| | - Tianyu Yuan
- Integrated Graduate Program in Physics Engineering Biology, Yale University, New Haven, CT 06511
- Department of Physics, Yale University, New Haven, CT 06511
| | - Kevin Li
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | - Katherine Duseau
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | - Simon G. J. Mochrie
- Department of Applied Physics, Yale University, New Haven, CT 06511
- Integrated Graduate Program in Physics Engineering Biology, Yale University, New Haven, CT 06511
- Department of Physics, Yale University, New Haven, CT 06511
| | - Megan C. King
- Integrated Graduate Program in Physics Engineering Biology, Yale University, New Haven, CT 06511
- Department of Molecular, Cell and Developmental Biology, Yale University, New Haven, CT 06511
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| |
Collapse
|
34
|
Liu Y, Cottle WT, Ha T. Mapping cellular responses to DNA double-strand breaks using CRISPR technologies. Trends Genet 2023; 39:560-574. [PMID: 36967246 PMCID: PMC11062594 DOI: 10.1016/j.tig.2023.02.015] [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: 09/22/2021] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 06/15/2023]
Abstract
DNA double-strand breaks (DSBs) are one of the most genotoxic DNA lesions, driving a range of pathological defects from cancers to immunodeficiencies. To combat genomic instability caused by DSBs, evolution has outfitted cells with an intricate protein network dedicated to the rapid and accurate repair of these lesions. Pioneering studies have identified and characterized many crucial repair factors in this network, while the advent of genome manipulation tools like clustered regularly interspersed short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) has reinvigorated interest in DSB repair mechanisms. This review surveys the latest methodological advances and biological insights gained by utilizing Cas9 as a precise 'damage inducer' for the study of DSB repair. We highlight rapidly inducible Cas9 systems that enable synchronized and efficient break induction. When combined with sequencing and genome-specific imaging approaches, inducible Cas9 systems greatly expand our capability to spatiotemporally characterize cellular responses to DSB at specific genomic coordinates, providing mechanistic insights that were previously unobtainable.
Collapse
Affiliation(s)
- Yang Liu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - W Taylor Cottle
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, USA
| | - Taekjip Ha
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA; Department of Biophysics, Johns Hopkins University, Baltimore, MD, USA; Howard Hughes Medical Institute, Baltimore, MD, USA.
| |
Collapse
|
35
|
Han JDJ. LncRNAs: the missing link to senescence nuclear architecture. Trends Biochem Sci 2023; 48:618-628. [PMID: 37069045 DOI: 10.1016/j.tibs.2023.03.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/24/2023] [Accepted: 03/24/2023] [Indexed: 04/19/2023]
Abstract
During cellular senescence and organismal aging, cells display various molecular and morphological changes. Although many aging-related long noncoding RNAs (lncRNAs) are highly associated with senescence-associated secretory phenotype, the roles of lncRNAs in senescence-associated nuclear architecture and morphological changes are just starting to emerge. Here I review lncRNAs associated with nuclear structure establishment and maintenance, their aging-related changes, and then focus on the pervasive, yet underappreciated, role of RNA double-strand DNA triplexes for lncRNAs to recognize targeted genomic regions, making lncRNAs the nexus between DNA and proteins to regulate nuclear structural changes. Finally, I discuss the future of deciphering direct links of lncRNA changes to various nuclear morphology changes assisted by artificial intelligence and genetic perturbations.
Collapse
Affiliation(s)
- Jing-Dong J Han
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Center for Quantitative Biology (CQB), Peking University, Beijing, China; International Center for Aging and Cancer (ICAC), The First Affiliated Hospital, Hainan Medical University, Haikou, China.
| |
Collapse
|
36
|
Shahid-Fuente IW, Toseland CP. Myosin in chromosome organisation and gene expression. Biochem Soc Trans 2023; 51:1023-1034. [PMID: 37171068 PMCID: PMC10317160 DOI: 10.1042/bst20220939] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 04/05/2023] [Accepted: 04/18/2023] [Indexed: 05/13/2023]
Abstract
The importance of myosin motor protein is well-characterised within the cytoplasm and cytoskeleton. However, mounting evidence on four nuclear myosins highlights the central role these proteins have in maintaining genomic stability and gene expression. This review focuses on each of their critical roles in chromatin structure, chromosome translocation, transcription regulation, and DNA damage repair in terms of maintaining chromosome and chromatin integrity.
Collapse
|
37
|
Shi J, Hauschulte K, Mikicic I, Maharjan S, Arz V, Strauch T, Heidelberger JB, Schaefer JV, Dreier B, Plückthun A, Beli P, Ulrich HD, Wollscheid HP. Nuclear myosin VI maintains replication fork stability. Nat Commun 2023; 14:3787. [PMID: 37355687 PMCID: PMC10290672 DOI: 10.1038/s41467-023-39517-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 06/09/2023] [Indexed: 06/26/2023] Open
Abstract
The actin cytoskeleton is of fundamental importance for cellular structure and plasticity. However, abundance and function of filamentous actin in the nucleus are still controversial. Here we show that the actin-based molecular motor myosin VI contributes to the stabilization of stalled or reversed replication forks. In response to DNA replication stress, myosin VI associates with stalled replication intermediates and cooperates with the AAA ATPase Werner helicase interacting protein 1 (WRNIP1) in protecting these structures from DNA2-mediated nucleolytic attack. Using functionalized affinity probes to manipulate myosin VI levels in a compartment-specific manner, we provide evidence for the direct involvement of myosin VI in the nucleus and against a contribution of the abundant cytoplasmic pool during the replication stress response.
Collapse
Affiliation(s)
- Jie Shi
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
| | - Kristine Hauschulte
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
| | - Ivan Mikicic
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
| | - Srijana Maharjan
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
- Mainz Biomed N.V., Robert-Koch-Str. 50, D - 55129, Mainz, Germany
| | - Valerie Arz
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
| | - Tina Strauch
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
| | - Jan B Heidelberger
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
- Max Planck School Matter to Life, Jahnstr. 29, D - 69120, Heidelberg, Germany
| | - Jonas V Schaefer
- University of Zurich, Department of Biochemistry, Winterthurerstr. 190, CH - 8057, Zurich, Switzerland
| | - Birgit Dreier
- University of Zurich, Department of Biochemistry, Winterthurerstr. 190, CH - 8057, Zurich, Switzerland
| | - Andreas Plückthun
- University of Zurich, Department of Biochemistry, Winterthurerstr. 190, CH - 8057, Zurich, Switzerland
| | - Petra Beli
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, Hanns-Dieter-Hüsch-Weg 15, D - 55128, Mainz, Germany
| | - Helle D Ulrich
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany.
| | - Hans-Peter Wollscheid
- Institute of Molecular Biology gGmbH (IMB), Ackermannweg 4, D - 55128, Mainz, Germany.
| |
Collapse
|
38
|
Alghoul E, Basbous J, Constantinou A. Compartmentalization of the DNA damage response: Mechanisms and functions. DNA Repair (Amst) 2023; 128:103524. [PMID: 37320957 DOI: 10.1016/j.dnarep.2023.103524] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/31/2023] [Accepted: 06/02/2023] [Indexed: 06/17/2023]
Abstract
Cells have evolved an arsenal of molecular mechanisms to respond to continuous alterations in the primary structure of DNA. At the cellular level, DNA damage response proteins accumulate at sites of DNA damage and organize into nuclear foci. As recounted by Errol Friedberg, pioneering work on DNA repair in the 1930 s was stimulated by collaborations between physicists and geneticists. In recent years, the introduction of ideas from physics on self-organizing compartments has taken the field of cell biology by storm. Percolation and phase separation theories are increasingly used to model the self-assembly of compartments, called biomolecular condensates, that selectively concentrate molecules without a surrounding membrane. In this review, we discuss these concepts in the context of the DNA damage response. We discuss how studies of DNA repair foci as condensates can link molecular mechanisms with cell physiological functions, provide new insights into regulatory mechanisms, and open new perspectives for targeting DNA damage responses for therapeutic purposes.
Collapse
Affiliation(s)
- Emile Alghoul
- Institut de Génétique Humaine, Université de Montpellier, CNRS, Montpellier, France
| | - Jihane Basbous
- Institut de Génétique Humaine, Université de Montpellier, CNRS, Montpellier, France
| | - Angelos Constantinou
- Institut de Génétique Humaine, Université de Montpellier, CNRS, Montpellier, France.
| |
Collapse
|
39
|
Peng XP, Zhao X. The multi-functional Smc5/6 complex in genome protection and disease. Nat Struct Mol Biol 2023; 30:724-734. [PMID: 37336994 PMCID: PMC10372777 DOI: 10.1038/s41594-023-01015-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/05/2023] [Indexed: 06/21/2023]
Abstract
Structural maintenance of chromosomes (SMC) complexes are ubiquitous genome regulators with a wide range of functions. Among the three types of SMC complexes in eukaryotes, cohesin and condensin fold the genome into different domains and structures, while Smc5/6 plays direct roles in promoting chromosomal replication and repair and in restraining pathogenic viral extra-chromosomal DNA. The importance of Smc5/6 for growth, genotoxin resistance and host defense across species is highlighted by its involvement in disease prevention in plants and animals. Accelerated progress in recent years, including structural and single-molecule studies, has begun to provide greater insights into the mechanisms underlying Smc5/6 functions. Here we integrate a broad range of recent studies on Smc5/6 to identify emerging features of this unique SMC complex and to explain its diverse cellular functions and roles in disease pathogenesis. We also highlight many key areas requiring further investigation for achieving coherent views of Smc5/6-driven mechanisms.
Collapse
Affiliation(s)
- Xiao P Peng
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiaolan Zhao
- Molecular Biology Program, Sloan Kettering Cancer Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| |
Collapse
|
40
|
Tolokh IS, Kinney NA, Sharakhov IV, Onufriev AV. Strong interactions between highly dynamic lamina-associated domains and the nuclear envelope stabilize the 3D architecture of Drosophila interphase chromatin. Epigenetics Chromatin 2023; 16:21. [PMID: 37254161 PMCID: PMC10228000 DOI: 10.1186/s13072-023-00492-9] [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: 01/19/2023] [Accepted: 05/04/2023] [Indexed: 06/01/2023] Open
Abstract
BACKGROUND Interactions among topologically associating domains (TADs), and between the nuclear envelope (NE) and lamina-associated domains (LADs) are expected to shape various aspects of three-dimensional (3D) chromatin structure and dynamics; however, relevant genome-wide experiments that may provide statistically significant conclusions remain difficult. RESULTS We have developed a coarse-grained dynamical model of D. melanogaster nuclei at TAD resolution that explicitly accounts for four distinct epigenetic classes of TADs and LAD-NE interactions. The model is parameterized to reproduce the experimental Hi-C map of the wild type (WT) nuclei; it describes time evolution of the chromatin over the G1 phase of the interphase. The simulations include an ensemble of nuclei, corresponding to the experimentally observed set of several possible mutual arrangements of chromosomal arms. The model is validated against multiple structural features of chromatin from several different experiments not used in model development. Predicted positioning of all LADs at the NE is highly dynamic-the same LAD can attach, detach and move far away from the NE multiple times during interphase. The probabilities of LADs to be in contact with the NE vary by an order of magnitude, despite all having the same affinity to the NE in the model. These probabilities are mostly determined by a highly variable local linear density of LADs along the genome, which also has the same strong effect on the predicted positioning of individual TADs -- higher probability of a TAD to be near NE is largely determined by a higher linear density of LADs surrounding this TAD. The distribution of LADs along the chromosome chains plays a notable role in maintaining a non-random average global structure of chromatin. Relatively high affinity of LADs to the NE in the WT nuclei substantially reduces sensitivity of the global radial chromatin distribution to variations in the strength of TAD-TAD interactions compared to the lamin depleted nuclei, where a small (0.5 kT) increase of cross-type TAD-TAD interactions doubles the chromatin density in the central nucleus region. CONCLUSIONS A dynamical model of the entire fruit fly genome makes multiple genome-wide predictions of biological interest. The distribution of LADs along the chromatin chains affects their probabilities to be in contact with the NE and radial positioning of highly mobile TADs, playing a notable role in creating a non-random average global structure of the chromatin. We conjecture that an important role of attractive LAD-NE interactions is to stabilize global chromatin structure against inevitable cell-to-cell variations in TAD-TAD interactions.
Collapse
Affiliation(s)
- Igor S. Tolokh
- Department of Computer Science, Virginia Tech, Blacksburg, VA 24061 USA
| | - Nicholas Allen Kinney
- Department of Computer Science, Virginia Tech, Blacksburg, VA 24061 USA
- Department of Entomology, Virginia Tech, Blacksburg, VA 24061 USA
- Edward Via College of Osteopathic Medicine, 2265 Kraft Drive, Blacksburg, VA 24060 USA
| | | | - Alexey V. Onufriev
- Department of Computer Science, Virginia Tech, Blacksburg, VA 24061 USA
- Department of Physics, Virginia Tech, Blacksburg, VA 24061 USA
- Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA 24061 USA
| |
Collapse
|
41
|
Sadhu L, Tsopoulidis N, Hasanuzzaman M, Laketa V, Way M, Fackler OT. ARPC5 isoforms and their regulation by calcium-calmodulin-N-WASP drive distinct Arp2/3-dependent actin remodeling events in CD4 T cells. eLife 2023; 12:e82450. [PMID: 37162507 PMCID: PMC10171864 DOI: 10.7554/elife.82450] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 04/06/2023] [Indexed: 05/11/2023] Open
Abstract
CD4 T cell activation induces nuclear and cytoplasmic actin polymerization via the Arp2/3 complex to activate cytokine expression and strengthen T cell receptor (TCR) signaling. Actin polymerization dynamics and filament morphology differ between nucleus and cytoplasm. However, it is unclear how the Arp2/3 complex mediates distinct nuclear and cytoplasmic actin polymerization in response to a common stimulus. In humans, the ARP3, ARPC1, and ARPC5 subunits of the Arp2/3 complex exist as two different isoforms, resulting in complexes with different properties. Here, we show that the Arp2/3 subunit isoforms ARPC5 and ARPC5L play a central role in coordinating distinct actin polymerization events in CD4 T cells. While ARPC5L is heterogeneously expressed in individual CD4 T cells, it specifically drives nuclear actin polymerization upon T cell activation. In contrast, ARPC5 is evenly expressed in CD4 T cell populations and is required for cytoplasmic actin dynamics. Interestingly, nuclear actin polymerization triggered by a different stimulus, DNA replication stress, specifically requires ARPC5 but not ARPC5L. TCR signaling but not DNA replication stress induces nuclear actin polymerization via nuclear calcium-calmodulin signaling and N-WASP. Diversity in the molecular properties and individual expression patterns of ARPC5 subunit isoforms thus tailors Arp2/3-mediated actin polymerization to different physiological stimuli.
Collapse
Affiliation(s)
- Lopamudra Sadhu
- Department of Infectious Diseases, Integrative Virology, University Hospital HeidelbergHeidelbergGermany
| | - Nikolaos Tsopoulidis
- Department of Infectious Diseases, Integrative Virology, University Hospital HeidelbergHeidelbergGermany
| | - Md Hasanuzzaman
- Department of Infectious Diseases, Integrative Virology, University Hospital HeidelbergHeidelbergGermany
| | - Vibor Laketa
- Department of Infectious Diseases, Virology, University Hospital HeidelbergHeidelbergGermany
| | - Michael Way
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick InstituteLondonUnited Kingdom
- Department of Infectious Disease, Imperial CollegeLondonUnited Kingdom
| | - Oliver T Fackler
- Department of Infectious Diseases, Integrative Virology, University Hospital HeidelbergHeidelbergGermany
| |
Collapse
|
42
|
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
|
43
|
Huang J, Wu C, Kloeber JA, Gao H, Gao M, Zhu Q, Chang Y, Zhao F, Guo G, Luo K, Dai H, Liu S, Huang Q, Kim W, Zhou Q, Zhu S, Wu Z, Tu X, Yin P, Deng M, Wang L, Yuan J, Lou Z. SLFN5-mediated chromatin dynamics sculpt higher-order DNA repair topology. Mol Cell 2023; 83:1043-1060.e10. [PMID: 36854302 PMCID: PMC10467573 DOI: 10.1016/j.molcel.2023.02.004] [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: 05/17/2022] [Revised: 12/23/2022] [Accepted: 02/01/2023] [Indexed: 03/02/2023]
Abstract
Repair of DNA double-strand breaks (DSBs) elicits three-dimensional (3D) chromatin topological changes. A recent finding reveals that 53BP1 assembles into a 3D chromatin topology pattern around DSBs. How this formation of a higher-order structure is configured and regulated remains enigmatic. Here, we report that SLFN5 is a critical factor for 53BP1 topological arrangement at DSBs. Using super-resolution imaging, we find that SLFN5 binds to 53BP1 chromatin domains to assemble a higher-order microdomain architecture by driving damaged chromatin dynamics at both DSBs and deprotected telomeres. Mechanistically, we propose that 53BP1 topology is shaped by two processes: (1) chromatin mobility driven by the SLFN5-LINC-microtubule axis and (2) the assembly of 53BP1 oligomers mediated by SLFN5. In mammals, SLFN5 deficiency disrupts the DSB repair topology and impairs non-homologous end joining, telomere fusions, class switch recombination, and sensitivity to poly (ADP-ribose) polymerase inhibitor. We establish a molecular mechanism that shapes higher-order chromatin topologies to safeguard genomic stability.
Collapse
Affiliation(s)
- Jinzhou Huang
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Chenming Wu
- Key Laboratory of Arrhythmias of the Ministry of Education of China, Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Jake A Kloeber
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA; Medical Scientist Training Program, Mayo Clinic, Rochester, MN 55905, USA
| | - Huanyao Gao
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA
| | - Ming Gao
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Qian Zhu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Yiming Chang
- Jinzhou Medical University, Shanghai East Hospital, Shanghai 200120, China
| | - Fei Zhao
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Guijie Guo
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Kuntian Luo
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Haiming Dai
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Sijia Liu
- Department of Artificial Intelligence and Informatics, Mayo Clinic, Rochester, MN 55905, USA
| | - Qiru Huang
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Wootae Kim
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Qin Zhou
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Shouhai Zhu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Zheming Wu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Xinyi Tu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Ping Yin
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Min Deng
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA
| | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA
| | - Jian Yuan
- Key Laboratory of Arrhythmias of the Ministry of Education of China, Research Center for Translational Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China; Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai 200092, China.
| | - Zhenkun Lou
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, USA.
| |
Collapse
|
44
|
Rubio LS, Gross DS. Dynamic coalescence of yeast Heat Shock Protein genes bypasses the requirement for actin. Genetics 2023; 223:iyad006. [PMID: 36659814 PMCID: PMC10319981 DOI: 10.1093/genetics/iyad006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 07/22/2022] [Accepted: 01/03/2023] [Indexed: 01/21/2023] Open
Abstract
Nuclear actin has been implicated in dynamic chromatin rearrangements in diverse eukaryotes. In mammalian cells, it is required to reposition double-strand DNA breaks to enable homologous recombination repair and to enhance transcription by facilitating RNA Pol II recruitment to gene promoters. In the yeast Saccharomyces cerevisiae, nuclear actin modulates interphase chromosome dynamics and is required to reposition the induced INO1 gene to the nuclear periphery. Here, we have investigated the role of actin in driving intergenic interactions between Heat Shock Factor 1 (Hsf1)-regulated Heat Shock Protein (HSP) genes in budding yeast. These genes, dispersed on multiple chromosomes, dramatically reposition following exposure of cells to acute thermal stress, leading to their clustering within dynamic biomolecular condensates. Using an auxin-induced degradation strategy, we found that conditional depletion of nucleators of either linear or branched F-actin (Bni1/Bnr1 and Arp2, respectively) had little or no effect on heat shock-induced HSP gene coalescence or transcription. In addition, we found that pretreatment of cells with latrunculin A, an inhibitor of both filamentous and monomeric actin, failed to affect intergenic interactions between activated HSP genes and their heat shock-induced intragenic looping and folding. Moreover, latrunculin A pretreatment had little effect on HSP gene expression at either RNA or protein levels. In notable contrast, we confirmed that repositioning of activated INO1 to the nuclear periphery and its proper expression do require actin. Collectively, our work suggests that transcriptional activation and 3D genome restructuring of thermally induced, Hsf1-regulated genes can occur in the absence of actin.
Collapse
Affiliation(s)
- Linda S Rubio
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA
| | - David S Gross
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA
| |
Collapse
|
45
|
Moustafa A, Hashemi S, Brar G, Grigull J, Ng SHS, Williams D, Schmitt-Ulms G, McDermott JC. The MEF2A transcription factor interactome in cardiomyocytes. Cell Death Dis 2023; 14:240. [PMID: 37019881 PMCID: PMC10076289 DOI: 10.1038/s41419-023-05665-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 12/02/2022] [Accepted: 02/08/2023] [Indexed: 04/07/2023]
Abstract
Transcriptional regulators encoded by the Myocyte Enhancer Factor 2 (MEF2) gene family play a fundamental role in cardiac development, homeostasis and pathology. Previous studies indicate that MEF2A protein-protein interactions serve as a network hub in several cardiomyocyte cellular processes. Based on the idea that interactions with regulatory protein partners underly the diverse roles of MEF2A in cardiomyocyte gene expression, we undertook a systematic unbiased screen of the MEF2A protein interactome in primary cardiomyocytes using an affinity purification-based quantitative mass spectrometry approach. Bioinformatic processing of the MEF2A interactome revealed protein networks involved in the regulation of programmed cell death, inflammatory responses, actin dynamics and stress signaling in primary cardiomyocytes. Further biochemical and functional confirmation of specific protein-protein interactions documented a dynamic interaction between MEF2A and STAT3 proteins. Integration of transcriptome level data from MEF2A and STAT3-depleted cardiomyocytes reveals that the balance between MEF2A and STAT3 activity exerts a level of executive control over the inflammatory response and cardiomyocyte cell survival and experimentally ameliorates Phenylephrine induced cardiomyocyte hypertrophy. Lastly, we identified several MEF2A/STAT3 co-regulated genes, including the MMP9 gene. Herein, we document the cardiomyocyte MEF2A interactome, which furthers our understanding of protein networks involved in the hierarchical control of normal and pathophysiological cardiomyocyte gene expression in the mammalian heart.
Collapse
Affiliation(s)
- Amira Moustafa
- Department of Biology, York University, Toronto, ON, M3J 1P3, Canada
- Muscle Health Research Centre (MHRC), York University, Toronto, ON, M3J 1P3, Canada
- Centre for Research in Biomolecular Interactions (CRBI), York University, Toronto, ON, M3J 1P3, Canada
| | - Sara Hashemi
- Analytical Sciences, Sanofi, Toronto, ON, M2R 3T4, Canada
- Seneca College, School of Health Sciences, King City, ON, L7B 1B3, Canada
| | - Gurnoor Brar
- Department of Biology, York University, Toronto, ON, M3J 1P3, Canada
- Muscle Health Research Centre (MHRC), York University, Toronto, ON, M3J 1P3, Canada
- Centre for Research in Biomolecular Interactions (CRBI), York University, Toronto, ON, M3J 1P3, Canada
| | - Jörg Grigull
- Department of Mathematics and Statistics, York University, Toronto, ON, M3J1P3, Canada
| | - Siemon H S Ng
- Analytical Sciences, Sanofi, Toronto, ON, M2R 3T4, Canada
- Analytical Development, Notch Therapeutics, Toronto, ON, M5G 1M1, Canada
| | - Declan Williams
- Tanz Centre for Research in Neurodegenerative Diseases, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 0S8, Canada
| | - Gerold Schmitt-Ulms
- Tanz Centre for Research in Neurodegenerative Diseases, and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 0S8, Canada
| | - John C McDermott
- Department of Biology, York University, Toronto, ON, M3J 1P3, Canada.
- Muscle Health Research Centre (MHRC), York University, Toronto, ON, M3J 1P3, Canada.
- Centre for Research in Biomolecular Interactions (CRBI), York University, Toronto, ON, M3J 1P3, Canada.
| |
Collapse
|
46
|
Debaugnies M, Rodríguez-Acebes S, Blondeau J, Parent MA, Zocco M, Song Y, de Maertelaer V, Moers V, Latil M, Dubois C, Coulonval K, Impens F, Van Haver D, Dufour S, Uemura A, Sotiropoulou PA, Méndez J, Blanpain C. RHOJ controls EMT-associated resistance to chemotherapy. Nature 2023; 616:168-175. [PMID: 36949199 PMCID: PMC10076223 DOI: 10.1038/s41586-023-05838-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 02/14/2023] [Indexed: 03/24/2023]
Abstract
The resistance of cancer cells to therapy is responsible for the death of most patients with cancer1. Epithelial-to-mesenchymal transition (EMT) has been associated with resistance to therapy in different cancer cells2,3. However, the mechanisms by which EMT mediates resistance to therapy remain poorly understood. Here, using a mouse model of skin squamous cell carcinoma undergoing spontaneous EMT during tumorigenesis, we found that EMT tumour cells are highly resistant to a wide range of anti-cancer therapies both in vivo and in vitro. Using gain and loss of function studies in vitro and in vivo, we found that RHOJ-a small GTPase that is preferentially expressed in EMT cancer cells-controls resistance to therapy. Using genome-wide transcriptomic and proteomic profiling, we found that RHOJ regulates EMT-associated resistance to chemotherapy by enhancing the response to replicative stress and activating the DNA-damage response, enabling tumour cells to rapidly repair DNA lesions induced by chemotherapy. RHOJ interacts with proteins that regulate nuclear actin, and inhibition of actin polymerization sensitizes EMT tumour cells to chemotherapy-induced cell death in a RHOJ-dependent manner. Together, our study uncovers the role and the mechanisms through which RHOJ acts as a key regulator of EMT-associated resistance to chemotherapy.
Collapse
Affiliation(s)
- Maud Debaugnies
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
- CHU Saint-Pierre, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Sara Rodríguez-Acebes
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre, Madrid, Spain
| | - Jeremy Blondeau
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Marie-Astrid Parent
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Manuel Zocco
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Yura Song
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Viviane de Maertelaer
- Institute of Interdisciplinary Research (IRIBHM), Université Libre de Bruxelles (ULB), Brussels, Belgium
- ULB-Cancer Research Center (U-crc), Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Virginie Moers
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Mathilde Latil
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Christine Dubois
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium
| | - Katia Coulonval
- Institute of Interdisciplinary Research (IRIBHM), Université Libre de Bruxelles (ULB), Brussels, Belgium
- ULB-Cancer Research Center (U-crc), Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Francis Impens
- VIB Center for Medical Biotechnology, VIB Proteomics Core, Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Delphi Van Haver
- VIB Center for Medical Biotechnology, VIB Proteomics Core, Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Sara Dufour
- VIB Center for Medical Biotechnology, VIB Proteomics Core, Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Akiyoshi Uemura
- Department of Retinal Vascular Biology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | | | - Juan Méndez
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre, Madrid, Spain
| | - Cédric Blanpain
- Laboratory of Stem Cells and Cancer, Université Libre de Buxelles (ULB), Brussels, Belgium.
- WELBIO, Université Libre de Bruxelles (ULB), Brussels, Belgium.
| |
Collapse
|
47
|
Palumbieri MD, Merigliano C, Acosta DG, von Känel T, Welter B, Stoy H, Krietsch J, Ulferts S, Sanchi A, Grosse R, Chiolo I, Lopes M. Replication fork plasticity upon replication stress requires rapid nuclear actin polymerization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.24.534097. [PMID: 36993227 PMCID: PMC10055433 DOI: 10.1101/2023.03.24.534097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Cells rapidly respond to replication stress actively slowing fork progression and inducing fork reversal. How replication fork plasticity is achieved in the context of nuclear organization is currently unknown. Using nuclear actin probes in living and fixed cells, we visualized nuclear actin filaments in unperturbed S phase, rapidly extending in number and thickness upon genotoxic treatments, and taking frequent contact with replication factories. Chemically or genetically impairing nuclear actin polymerization shortly before these treatments prevents active fork slowing and abolishes fork reversal. Defective fork plasticity is linked to reduced recruitment of RAD51 and SMARCAL1 to nascent DNA. Conversely, PRIMPOL gains access to replicating chromatin, promoting unrestrained and discontinuous DNA synthesis, which is associated with increased chromosomal instability and decreased cellular resistance to replication stress. Hence, nuclear F-actin orchestrates replication fork plasticity and is a key molecular determinant in the rapid cellular response to genotoxic treatments.
Collapse
|
48
|
Campellone KG, Lebek NM, King VL. Branching out in different directions: Emerging cellular functions for the Arp2/3 complex and WASP-family actin nucleation factors. Eur J Cell Biol 2023; 102:151301. [PMID: 36907023 DOI: 10.1016/j.ejcb.2023.151301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 02/07/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
The actin cytoskeleton impacts practically every function of a eukaryotic cell. Historically, the best-characterized cytoskeletal activities are in cell morphogenesis, motility, and division. The structural and dynamic properties of the actin cytoskeleton are also crucial for establishing, maintaining, and changing the organization of membrane-bound organelles and other intracellular structures. Such activities are important in nearly all animal cells and tissues, although distinct anatomical regions and physiological systems rely on different regulatory factors. Recent work indicates that the Arp2/3 complex, a broadly expressed actin nucleator, drives actin assembly during several intracellular stress response pathways. These newly described Arp2/3-mediated cytoskeletal rearrangements are coordinated by members of the Wiskott-Aldrich Syndrome Protein (WASP) family of actin nucleation-promoting factors. Thus, the Arp2/3 complex and WASP-family proteins are emerging as crucial players in cytoplasmic and nuclear activities including autophagy, apoptosis, chromatin dynamics, and DNA repair. Characterizations of the functions of the actin assembly machinery in such stress response mechanisms are advancing our understanding of both normal and pathogenic processes, and hold great promise for providing insights into organismal development and interventions for disease.
Collapse
Affiliation(s)
- Kenneth G Campellone
- Department of Molecular and Cell Biology, Institute for Systems Genomics; University of Connecticut; Storrs, CT, USA.
| | - Nadine M Lebek
- Department of Molecular and Cell Biology, Institute for Systems Genomics; University of Connecticut; Storrs, CT, USA
| | - Virginia L King
- Department of Molecular and Cell Biology, Institute for Systems Genomics; University of Connecticut; Storrs, CT, USA
| |
Collapse
|
49
|
Stromberg KA, Spain T, Tomlin SA, Amarillo KD, Schroeder CM. Evolutionary diversification reveals distinct somatic versus germline cytoskeletal functions of the Arp2 branched actin nucleator protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.25.530036. [PMID: 36909544 PMCID: PMC10002617 DOI: 10.1101/2023.02.25.530036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Branched actin networks are critical in many cellular processes, including cell motility and division. Arp2, a protein within the 7-membered Arp2/3 complex, is responsible for generating branched actin. Given its essential roles, Arp2 evolves under stringent sequence conservation throughout eukaryotic evolution. We unexpectedly discovered recurrent evolutionary diversification of Arp2 in Drosophila, yielding independently arising paralogs Arp2D in obscura species and Arp2D2 in montium species. Both paralogs are unusually testis-enriched in expression relative to Arp2. We investigated whether their sequence divergence from canonical Arp2 led to functional specialization by replacing Arp2 in D. melanogaster with either Arp2D or Arp2D2. Despite their divergence, we surprisingly found both complement Arp2's essential function in the soma, suggesting they have preserved the ability to polymerize branched actin even in a non-native species. However, we found that Arp2D-expressing males are subfertile and display many defects throughout sperm development. We pinpointed two highly diverged structural regions in Arp2D that contribute to these defects: subdomain 2 and the C-terminus. We expected that germline function would be rescued by replacing Arp2D's long and charged C-terminus with Arp2's short C-terminus, yet surprisingly, the essential somatic function of Arp2D was lost. Therefore, while Arp2D's structural divergence is incompatible with D. melanogaster sperm development, its unique C-terminus has evolved a critical role in actin polymerization. Our findings suggest canonical Arp2's function differs between somatic versus germline contexts, and Arp2 paralogs have recurrently evolved and specialized for actin branching in the testis.
Collapse
Affiliation(s)
| | - Tristan Spain
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX
| | - Sarah A. Tomlin
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA
| | | | | |
Collapse
|
50
|
Puccini J, Wei J, Tong L, Bar-Sagi D. Cytoskeletal association of ATP citrate lyase controls the mechanodynamics of macropinocytosis. Proc Natl Acad Sci U S A 2023; 120:e2213272120. [PMID: 36787367 PMCID: PMC9974455 DOI: 10.1073/pnas.2213272120] [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: 01/15/2023] [Indexed: 02/15/2023] Open
Abstract
Macropinocytosis is an actin-dependent mode of nonselective endocytosis that mediates the uptake of extracellular fluid-phase cargoes. It is now well recognized that tumor cells exploit macropinocytosis to internalize macromolecules that can be catabolized and used to support cell growth and proliferation under nutrient-limiting conditions. Therefore, the identification of molecular mechanisms that control macropinocytosis is fundamental to the understanding of the metabolic adaptive landscape of tumor cells. Here, we report that the acetyl-CoA-producing enzyme, ATP citrate lyase (ACLY), is a key regulator of macropinocytosis and describes a heretofore-unappreciated association of ACLY with the actin cytoskeleton. The cytoskeletal tethering of ACLY is required for the spatially defined acetylation of heterodimeric actin capping protein, which we identify as an essential mediator of the actin remodeling events that drive membrane ruffling and macropinocytosis. Furthermore, we identify a requirement for mitochondrial-derived citrate, an ACLY substrate, for macropinocytosis, and show that mitochondria traffic to cell periphery regions juxtaposed to plasma membrane ruffles. Collectively, these findings establish a mode of metabolite compartmentalization that supports the spatiotemporal modulation of membrane-cytoskeletal interactions required for macropinocytosis by coupling regional acetyl-CoA availability with dynamic protein acetylation.
Collapse
Affiliation(s)
- Joseph Puccini
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY10016
| | - Jia Wei
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Dafna Bar-Sagi
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY10016
| |
Collapse
|