1
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Anderson CL, Brown KA, North RJ, Walters JK, Kaska ST, Wolff MR, Kamp TJ, Ge Y, Eckhardt LL. Global Proteomic Analysis Reveals Alterations in Differentially Expressed Proteins between Cardiopathic Lamin A/C Mutations. J Proteome Res 2024. [PMID: 38718259 DOI: 10.1021/acs.jproteome.3c00853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2024]
Abstract
Lamin A/C (LMNA) is an important component of nuclear lamina. Mutations cause arrhythmia, heart failure, and sudden cardiac death. While LMNA-associated cardiomyopathy typically has an aggressive course that responds poorly to conventional heart failure therapies, there is variability in severity and age of penetrance between and even within specific mutations, which is poorly understood at the cellular level. Further, this heterogeneity has not previously been captured to mimic the heterozygous state, nor have the hundreds of clinical LMNA mutations been represented. Herein, we have overexpressed cardiopathic LMNA variants in HEK cells and utilized state-of-the-art quantitative proteomics to compare the global proteomic profiles of (1) aggregating Q353 K alone, (2) Q353 K coexpressed with WT, (3) aggregating N195 K coexpressed with WT, and (4) nonaggregating E317 K coexpressed with WT to help capture some of the heterogeneity between mutations. We analyzed each data set to obtain the differentially expressed proteins (DEPs) and applied gene ontology (GO) and KEGG pathway analyses. We found a range of 162 to 324 DEPs from over 6000 total protein IDs with differences in GO terms, KEGG pathways, and DEPs important in cardiac function, further highlighting the complexity of cardiac laminopathies. Pathways disrupted by LMNA mutations were validated with redox, autophagy, and apoptosis functional assays in both HEK 293 cells and in induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) for LMNA N195 K. These proteomic profiles expand our repertoire for mutation-specific downstream cellular effects that may become useful as druggable targets for personalized medicine approach for cardiac laminopathies.
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Affiliation(s)
- Corey L Anderson
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Kyle A Brown
- Department of Cell and Regenerative Biology, Human Proteomics Program, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Ryan J North
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Janay K Walters
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Sara T Kaska
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Mathew R Wolff
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Timothy J Kamp
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Ying Ge
- Department of Cell and Regenerative Biology, Human Proteomics Program, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Lee L Eckhardt
- Department of Medicine, Division of Cardiovascular Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
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2
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Gerbino A, Forleo C, Milano S, Piccapane F, Procino G, Pepe M, Piccolo M, Guida P, Resta N, Favale S, Svelto M, Carmosino M. Pro-inflammatory cytokines as emerging molecular determinants in cardiolaminopathies. J Cell Mol Med 2021; 25:10902-10915. [PMID: 34773379 PMCID: PMC8642682 DOI: 10.1111/jcmm.16975] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/16/2021] [Accepted: 09/23/2021] [Indexed: 12/12/2022] Open
Abstract
Mutations in Lamin A/C gene (lmna) cause a wide spectrum of cardiolaminopathies strictly associated with significant deterioration of the electrical and contractile function of the heart. Despite the continuous flow of biomedical evidence, linking cardiac inflammation to heart remodelling in patients harbouring lmna mutations is puzzling. Therefore, we profiled 30 serum cytokines/chemokines in patients belonging to four different families carrying pathogenic lmna mutations segregating with cardiac phenotypes at different stages of severity (n = 19) and in healthy subjects (n = 11). Regardless lmna mutation subtype, high levels of circulating granulocyte colony‐stimulating factor (G‐CSF) and interleukin 6 (IL‐6) were found in all affected patients’ sera. In addition, elevated levels of Interleukins (IL) IL‐1Ra, IL‐1β IL‐4, IL‐5 and IL‐8 and the granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) were measured in a large subset of patients associated with more aggressive clinical manifestations. Finally, the expression of the pro‐inflammatory 70 kDa heat shock protein (Hsp70) was significantly increased in serum exosomes of patients harbouring the lmna mutation associated with the more severe phenotype. Overall, the identification of patient subsets with overactive or dysregulated myocardial inflammatory responses could represent an innovative diagnostic, prognostic and therapeutic tool against Lamin A/C cardiomyopathies.
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Affiliation(s)
- Andrea Gerbino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Cinzia Forleo
- Department of Emergency and Organ Transplantation, Cardiology Unit, University of Bari Aldo Moro, Bari, Italy
| | - Serena Milano
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Francesca Piccapane
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Giuseppe Procino
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Martino Pepe
- Department of Emergency and Organ Transplantation, Cardiology Unit, University of Bari Aldo Moro, Bari, Italy
| | - Mara Piccolo
- Department of Emergency and Organ Transplantation, Cardiology Unit, University of Bari Aldo Moro, Bari, Italy
| | - Piero Guida
- Regional General Hospital "F. Miulli", Acquaviva delle Fonti, Italy
| | - Nicoletta Resta
- Division of Medical Genetics, Department of Biomedical Sciences and Human Oncology, University of Bari Aldo Moro, Bari, Italy
| | - Stefano Favale
- Department of Emergency and Organ Transplantation, Cardiology Unit, University of Bari Aldo Moro, Bari, Italy
| | - Maria Svelto
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Monica Carmosino
- Department of Sciences, University of Basilicata, Potenza, Italy
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3
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Lityagina O, Dobreva G. The LINC Between Mechanical Forces and Chromatin. Front Physiol 2021; 12:710809. [PMID: 34408666 PMCID: PMC8365421 DOI: 10.3389/fphys.2021.710809] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 07/14/2021] [Indexed: 12/26/2022] Open
Abstract
The heart continually senses and responds to mechanical stimuli that balance cardiac structure and activity. Tensile forces, compressive forces, and shear stress are sensed by the different cardiac cell types and converted into signals instructing proper heart morphogenesis, postnatal growth, and function. Defects in mechanotransduction, the ability of cells to convert mechanical stimuli into biochemical signals, are implicated in cardiovascular disease development and progression. In this review, we summarize the current knowledge on how mechanical forces are transduced to chromatin through the tensed actomyosin cytoskeleton, the linker of nucleoskeleton and cytoskeleton (LINC) complex and the nuclear lamina. We also discuss the functional significance of the LINC complex in cardiovascular disease.
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Affiliation(s)
- Olga Lityagina
- Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Gergana Dobreva
- Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.,German Centre for Cardiovascular Research (DZHK), Partner Site Heidelberg/Mannheim, Mannheim, Germany
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4
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Nothing Regular about the Regulins: Distinct Functional Properties of SERCA Transmembrane Peptide Regulatory Subunits. Int J Mol Sci 2021; 22:ijms22168891. [PMID: 34445594 PMCID: PMC8396278 DOI: 10.3390/ijms22168891] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/10/2021] [Accepted: 08/12/2021] [Indexed: 12/11/2022] Open
Abstract
The sarco-endoplasmic reticulum calcium ATPase (SERCA) is responsible for maintaining calcium homeostasis in all eukaryotic cells by actively transporting calcium from the cytosol into the sarco-endoplasmic reticulum (SR/ER) lumen. Calcium is an important signaling ion, and the activity of SERCA is critical for a variety of cellular processes such as muscle contraction, neuronal activity, and energy metabolism. SERCA is regulated by several small transmembrane peptide subunits that are collectively known as the “regulins”. Phospholamban (PLN) and sarcolipin (SLN) are the original and most extensively studied members of the regulin family. PLN and SLN inhibit the calcium transport properties of SERCA and they are required for the proper functioning of cardiac and skeletal muscles, respectively. Myoregulin (MLN), dwarf open reading frame (DWORF), endoregulin (ELN), and another-regulin (ALN) are newly discovered tissue-specific regulators of SERCA. Herein, we compare the functional properties of the regulin family of SERCA transmembrane peptide subunits and consider their regulatory mechanisms in the context of the physiological and pathophysiological roles of these peptides. We present new functional data for human MLN, ELN, and ALN, demonstrating that they are inhibitors of SERCA with distinct functional consequences. Molecular modeling and molecular dynamics simulations of SERCA in complex with the transmembrane domains of MLN and ALN provide insights into how differential binding to the so-called inhibitory groove of SERCA—formed by transmembrane helices M2, M6, and M9—can result in distinct functional outcomes.
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Onoue K, Wakimoto H, Jiang J, Parfenov M, DePalma S, Conner D, Gorham J, McKean D, Seidman JG, Seidman CE, Saito Y. Cardiomyocyte Proliferative Capacity Is Restricted in Mice With Lmna Mutation. Front Cardiovasc Med 2021; 8:639148. [PMID: 34250035 PMCID: PMC8260675 DOI: 10.3389/fcvm.2021.639148] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 05/21/2021] [Indexed: 02/01/2023] Open
Abstract
LMNA is one of the leading causative genes of genetically inherited dilated cardiomyopathy (DCM). Unlike most DCM-causative genes, which encode sarcomeric or sarcomere-related proteins, LMNA encodes nuclear envelope proteins, lamin A and C, and does not directly associate with contractile function. However, a mutation in this gene could lead to the development of DCM. The molecular mechanism of how LMNA mutation contributes to DCM development remains largely unclear and yet to be elucidated. The objective of this study was to clarify the mechanism of developing DCM caused by LMNA mutation. Methods and Results: We assessed cardiomyocyte phenotypes and characteristics focusing on cell cycle activity in mice with Lmna mutation. Both cell number and cell size were reduced, cardiomyocytes were immature, and cell cycle activity was retarded in Lmna mutant mice at both 5 weeks and 2 years of age. RNA-sequencing and pathway analysis revealed "proliferation of cells" had the most substantial impact on Lmna mutant mice. Cdkn1a, which encodes the cell cycle regulating protein p21, was strongly upregulated in Lmna mutants, and upregulation of p21 was confirmed by Western blot and immunostaining. DNA damage, which is known to upregulate Cdkn1a, was more abundantly detected in Lmna mutant mice. To assess the proliferative capacity of cardiomyocytes, the apex of the neonate mouse heart was resected, and recovery from the insult was observed. A restricted cardiomyocyte proliferating capacity after resecting the apex of the heart was observed in Lmna mutant mice. Conclusions: Our results strongly suggest that loss of lamin function contributes to impaired cell proliferation through cell cycle defects. The inadequate inborn or responsive cell proliferation capacity plays an essential role in developing DCM with LMNA mutation.
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Affiliation(s)
- Kenji Onoue
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara, Japan.,Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Hiroko Wakimoto
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Jiangming Jiang
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Michael Parfenov
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Steven DePalma
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - David Conner
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Joshua Gorham
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - David McKean
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Jonathan G Seidman
- Department of Genetics, Harvard Medical School, Boston, MA, United States
| | - Christine E Seidman
- Department of Genetics, Harvard Medical School, Boston, MA, United States.,Division of Cardiovascular Medicine, Howard Hughes Medical Institute, Brigham and Women's Hospital, Boston, MA, United States
| | - Yoshihiko Saito
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara, Japan
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6
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Bal NC, Gupta SC, Pant M, Sopariwala DH, Gonzalez-Escobedo G, Turner J, Gunn JS, Pierson CR, Harper SQ, Rafael-Fortney JA, Periasamy M. Is Upregulation of Sarcolipin Beneficial or Detrimental to Muscle Function? Front Physiol 2021; 12:633058. [PMID: 33732165 PMCID: PMC7956958 DOI: 10.3389/fphys.2021.633058] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/21/2021] [Indexed: 11/25/2022] Open
Abstract
Sarcolipin (SLN) is a regulator of sarco/endo plasmic reticulum Ca2+-ATPase (SERCA) pump and has been shown to be involved in muscle nonshivering thermogenesis (NST) and energy metabolism. Interestingly, SLN expression is significantly upregulated both during muscle development and in several disease states. However, the significance of altered SLN expression in muscle patho-physiology is not completely understood. We have previously shown that transgenic over-expression of SLN in skeletal muscle is not detrimental, and can promote oxidative metabolism and exercise capacity. In contrast, some studies have suggested that SLN upregulation in disease states is deleterious for muscle function and ablation of SLN can be beneficial. In this perspective article, we critically examine both published and some new data to determine the relevance of SLN expression to disease pathology. The new data presented in this paper show that SLN levels are induced in muscle during systemic bacterial (Salmonella) infection or lipopolysaccharides (LPS) treatment. We also present data showing that SLN expression is significantly upregulated in different types of muscular dystrophies including myotubular myopathy. These data taken together reveal that upregulation of SLN expression in muscle disease is progressive and increases with severity. Therefore, we suggest that increased SLN expression should not be viewed as the cause of the disease; rather, it is a compensatory response to meet the higher energy demand of the muscle. We interpret that higher SLN/SERCA ratio positively modulate cytosolic Ca2+ signaling pathways to promote mitochondrial biogenesis and oxidative metabolism to meet higher energy demand in muscle.
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Affiliation(s)
- Naresh C Bal
- School of Biotechnology, KIIT University, Bhubaneswar, India
| | - Subash C Gupta
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, United States.,Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Meghna Pant
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, United States
| | - Danesh H Sopariwala
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, United States
| | - Geoffrey Gonzalez-Escobedo
- Departments of Microbiology and Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States
| | - Joanne Turner
- Departments of Microbiology and Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States.,Texas Biomedical Research Institute, San Antonio, TX, United States
| | - John S Gunn
- Departments of Microbiology and Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States.,Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Christopher R Pierson
- Department of Pathology and Laboratory Medicine, Nationwide Children's Hospital, Columbus, OH, United States.,Department of Pathology, The Ohio State University, Columbus, OH, United States.,Department of Biomedical Education and Anatomy, The Ohio State University, Columbus, OH, United States
| | - Scott Q Harper
- Department of Laboratory Medicine, Nationwide Children's Hospital, Columbus, OH, United States
| | - Jill A Rafael-Fortney
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, United States
| | - Muthu Periasamy
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, United States.,Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
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Dridi H, Wu W, Reiken SR, Ofer RM, Liu Y, Yuan Q, Sittenfeld L, Kushner J, Muchir A, Worman HJ, Marks AR. Ryanodine receptor remodeling in cardiomyopathy and muscular dystrophy caused by lamin A/C gene mutation. Hum Mol Genet 2021; 29:3919-3934. [PMID: 33388782 PMCID: PMC7906753 DOI: 10.1093/hmg/ddaa278] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/08/2020] [Accepted: 12/23/2020] [Indexed: 01/06/2023] Open
Abstract
Mutations in the lamin A/C gene (LMNA), which encodes A-type lamins, cause several diseases called laminopathies, the most common of which is dilated cardiomyopathy with muscular dystrophy. The role of Ca2+ regulation in these diseases remain poorly understood. We now show biochemical remodeling of the ryanodine receptor (RyR)/intracellular Ca2+ release channel in heart samples from human subjects with LMNA mutations, including protein kinase A-catalyzed phosphorylation, oxidation and depletion of the stabilizing subunit calstabin. In the LmnaH222P/H222P murine model of Emery-Dreifuss muscular dystrophy caused by LMNA mutation, we demonstrate an age-dependent biochemical remodeling of RyR2 in the heart and RyR1 in skeletal muscle. This RyR remodeling is associated with heart and skeletal muscle dysfunction. Defective heart and muscle function are ameliorated by treatment with a novel Rycal small molecule drug (S107) that fixes 'leaky' RyRs. SMAD3 phosphorylation is increased in hearts and diaphragms of LmnaH222P/H222P mice, which enhances NADPH oxidase binding to RyR channels, contributing to their oxidation. There is also increased generalized protein oxidation, increased calcium/calmodulin-dependent protein kinase II-catalyzed phosphorylation of RyRs and increased protein kinase A activity in these tissues. Our data show that RyR remodeling plays a role in cardiomyopathy and skeletal muscle dysfunction caused by LMNA mutation and identify these Ca2+ channels as a potential therapeutic target.
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Affiliation(s)
- Haikel Dridi
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Wei Wu
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Steven R Reiken
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Rachel M Ofer
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Yang Liu
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Qi Yuan
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Leah Sittenfeld
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Jared Kushner
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
| | - Antoine Muchir
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, 75013 Paris, France
| | - Howard J Worman
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Department of Pathology and Cell Biology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Andrew R Marks
- Department of Physiology and Cellular Biophysics, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Wu Center for Molecular Cardiology, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia, University, New York, NY 10032, USA
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8
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Piccus R, Brayson D. The nuclear envelope: LINCing tissue mechanics to genome regulation in cardiac and skeletal muscle. Biol Lett 2020; 16:20200302. [PMID: 32634376 DOI: 10.1098/rsbl.2020.0302] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Regulation of the genome is viewed through the prism of gene expression, DNA replication and DNA repair as controlled through transcription, chromatin compartmentalisation and recruitment of repair factors by enzymes such as DNA polymerases, ligases, acetylases, methylases and cyclin-dependent kinases. However, recent advances in the field of muscle cell physiology have also shown a compelling role for 'outside-in' biophysical control of genomic material through mechanotransduction. The crucial hub that transduces these biophysical signals is called the Linker of Nucleoskeleton and Cytoskeleton (LINC). This complex is embedded across the nuclear envelope, which separates the nucleus from the cytoplasm. How the LINC complex operates to mechanically regulate the many functions of DNA is becoming increasingly clear, and recent advances have provided exciting insight into how this occurs in cells from mechanically activated tissues such as skeletal and cardiac muscle. Nevertheless, there are still some notable shortcomings in our understanding of these processes and resolving these will likely help us understand how muscle diseases manifest at the level of the genome.
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Affiliation(s)
- Rachel Piccus
- Centre for Human and Applied Physiological Sciences, King's College London, London SE1 1UL, UK
| | - Daniel Brayson
- School of Cardiovascular Medicine and Sciences, King's College London, London SE5 9NU, UK.,Molecular Neurosciences, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK
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