1
|
Nourisa J, Passemiers A, Shakeri F, Omidi M, Helmholz H, Raimondi D, Moreau Y, Tomforde S, Schlüter H, Luthringer-Feyerabend B, Cyron CJ, Aydin RC, Willumeit-Römer R, Zeller-Plumhoff B. Gene regulatory network analysis identifies MYL1, MDH2, GLS, and TRIM28 as the principal proteins in the response of mesenchymal stem cells to Mg 2+ ions. Comput Struct Biotechnol J 2024; 23:1773-1785. [PMID: 38689715 PMCID: PMC11058716 DOI: 10.1016/j.csbj.2024.04.033] [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: 12/15/2023] [Revised: 04/12/2024] [Accepted: 04/12/2024] [Indexed: 05/02/2024] Open
Abstract
Magnesium (Mg)-based implants have emerged as a promising alternative for orthopedic applications, owing to their bioactive properties and biodegradability. As the implants degrade, Mg2+ ions are released, influencing all surrounding cell types, especially mesenchymal stem cells (MSCs). MSCs are vital for bone tissue regeneration, therefore, it is essential to understand their molecular response to Mg2+ ions in order to maximize the potential of Mg-based biomaterials. In this study, we conducted a gene regulatory network (GRN) analysis to examine the molecular responses of MSCs to Mg2+ ions. We used time-series proteomics data collected at 11 time points across a 21-day period for the GRN construction. We studied the impact of Mg2+ ions on the resulting networks and identified the key proteins and protein interactions affected by the application of Mg2+ ions. Our analysis highlights MYL1, MDH2, GLS, and TRIM28 as the primary targets of Mg2+ ions in the response of MSCs during 1-21 days phase. Our results also identify MDH2-MYL1, MDH2-RPS26, TRIM28-AK1, TRIM28-SOD2, and GLS-AK1 as the critical protein relationships affected by Mg2+ ions. By offering a comprehensive understanding of the regulatory role of Mg2+ ions on MSCs, our study contributes valuable insights into the molecular response of MSCs to Mg-based materials, thereby facilitating the development of innovative therapeutic strategies for orthopedic applications.
Collapse
Affiliation(s)
- Jalil Nourisa
- Institute of Material Systems Modeling, Helmholtz Zentrum Hereon, Geesthacht, Germany
| | | | - Farhad Shakeri
- Institute of Medical Biometry, Informatics and Epidemiology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Maryam Omidi
- Institute of Clinical Chemistry/Central Laboratories, University Medical Center Hamburg, Hamburg, Germany
| | - Heike Helmholz
- Institute of Metallic Biomaterials, Helmholtz Zentrum Hereon, Geesthacht, Germany
| | | | | | - Sven Tomforde
- Department of Computer Science, Intelligent Systems, University of Kiel, Kiel, Germany
| | - Hartmuth Schlüter
- Institute of Clinical Chemistry and Laboratory Medicine Diagnostic Center, University of Hamburg, Hamburg, Germany
| | | | - Christian J. Cyron
- Institute of Material Systems Modeling, Helmholtz Zentrum Hereon, Geesthacht, Germany
- Institute for Continuum and Material Mechanics, Hamburg University of Technology, Hamburg, Germany
| | - Roland C. Aydin
- Institute of Material Systems Modeling, Helmholtz Zentrum Hereon, Geesthacht, Germany
- Institute for Continuum and Material Mechanics, Hamburg University of Technology, Hamburg, Germany
| | | | | |
Collapse
|
2
|
Gerzen O, Potoskueva I, Votinova V, Sergeeva K, Tyganov S, Tzybina A, Shenkman BS, Nikitina L. Mechanical interaction of myosin and native thin filament in the disused rat soleus muscle. LIFE SCIENCES IN SPACE RESEARCH 2024; 41:80-85. [PMID: 38670656 DOI: 10.1016/j.lssr.2024.01.009] [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: 08/19/2023] [Revised: 01/22/2024] [Accepted: 01/31/2024] [Indexed: 04/28/2024]
Abstract
The disuse of skeletal limb muscles occurs in a variety of conditions, yet our comprehension of the molecular mechanisms involved in adaptation to disuse remains incomplete. We studied the mechanical characteristics of actin-myosin interaction using an in vitro motility assay and isoform composition of myosin heavy and light chains by dint of SDS-PAGE in soleus muscle of both control and hindlimb-unloaded rats. 14 days of hindlimb unloading led to the increased maximum sliding velocity of actin, reconstituted, and native thin filaments over rat soleus muscle myosin by 24 %, 19 %, and 20 %, respectively. The calcium sensitivity of the "pCa-velocity" relationship decreased. There was a 26 % increase in fast myosin heavy chain IIa (MHC IIa), a 22 % increase in fast myosin light chain 2 (MLC 2f), and a 13 % increase in fast MLC 1f content. The content of MLC 1s/v, typical for slow skeletal muscles and cardiac ventricles did not change. At the same time, MLC 1s, typical only for slow skeletal muscles, disappeared. The maximum velocity of soleus muscle native thin filaments was 24 % higher compared to control ones sliding over the same rabbit myosin. Therefore, both myosin and native thin filament kinetics could influence the mechanical characteristics of the soleus muscle. Additionally, the MLC 1s and MLC 1s/v ratio may contribute to the mechanical characteristics of slow skeletal muscle, along with MHC, MLC 2, and MLC 1 slow/fast isoforms ratio.
Collapse
Affiliation(s)
- Oksana Gerzen
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia; Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia.
| | - Iulia Potoskueva
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
| | - Veronika Votinova
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
| | - Ksenia Sergeeva
- Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Sergey Tyganov
- Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Alena Tzybina
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
| | - Boris S Shenkman
- Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Larisa Nikitina
- Institute of Immunology and Physiology, Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia
| |
Collapse
|
3
|
Al Sultan A, Rattray Z, Rattray NJW. Cytotoxicity and toxicoproteomics analysis of thiazolidinedione exposure in human-derived cardiomyocytes. J Appl Toxicol 2024. [PMID: 38654465 DOI: 10.1002/jat.4613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 03/16/2024] [Accepted: 04/02/2024] [Indexed: 04/26/2024]
Abstract
Thiazolidinediones (TZDs) (e.g. pioglitazone and rosiglitazone), known insulin sensitiser agents for type II diabetes mellitus, exhibit controversial effects on cardiac tissue. Despite consensus on their association with increased heart failure risk, limiting TZD use in diabetes management, the underlying mechanisms remain uncharacterised. Herein, we report a comprehensive in vitro investigation utilising a novel toxicoproteomics pipeline coupled with cytotoxicity assays in human adult cardiomyocytes to elucidate mechanistic insights into TZD cardiotoxicity. The cytotoxicity assay findings showed a significant loss of mitochondrial adenosine triphosphate production upon exposure to either TZD agents, which may underpin TZD cardiotoxicity. Our toxicoproteomics analysis revealed that mitochondrial dysfunction primarily stems from oxidative phosphorylation impairment, with distinct signalling mechanisms observed for both agents. The type of cell death differed strikingly between the two agents, with rosiglitazone exhibiting features of caspase-dependent apoptosis and pioglitazone implicating mitochondrial-mediated necroptosis, as evidenced by the protein upregulation in the phosphoglycerate mutase family 5-dynamin-related protein 1 axis. Furthermore, our analysis revealed additional mechanistic aspects of cardiotoxicity, showcasing drug specificity. The downregulation of various proteins involved in protein machinery and protein processing in the endoplasmic reticulum was observed in rosiglitazone-treated cells, implicating proteostasis in the rosiglitazone cardiotoxicity. Regarding pioglitazone, the findings suggested the potential activation of the interplay between the complement and coagulation systems and the disruption of the cytoskeletal architecture, which was primarily mediated through the integrin-signalling pathways responsible for pioglitazone-induced myocardial contractile failure. Collectively, this study unlocks substantial mechanistic insight into TZD cardiotoxicity, providing the rationale for future optimisation of antidiabetic therapies.
Collapse
Affiliation(s)
- Abdullah Al Sultan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
- Faculty of Pharmacy, Kuwait University, Safat, Kuwait
| | - Zahra Rattray
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Nicholas J W Rattray
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| |
Collapse
|
4
|
Racine JJ, Bachman JF, Zhang JG, Misherghi A, Khadour R, Kaisar S, Bedard O, Jenkins C, Abbott A, Forte E, Rainer P, Rosenthal N, Sattler S, Serreze DV. Murine MHC-Deficient Nonobese Diabetic Mice Carrying Human HLA-DQ8 Develop Severe Myocarditis and Myositis in Response to Anti-PD-1 Immune Checkpoint Inhibitor Cancer Therapy. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 212:1287-1306. [PMID: 38426910 PMCID: PMC10984778 DOI: 10.4049/jimmunol.2300841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 02/08/2024] [Indexed: 03/02/2024]
Abstract
Myocarditis has emerged as an immune-related adverse event of immune checkpoint inhibitor (ICI) cancer therapy associated with significant mortality. To ensure patients continue to safely benefit from life-saving cancer therapy, an understanding of fundamental immunological phenomena underlying ICI myocarditis is essential. We recently developed the NOD-cMHCI/II-/-.DQ8 mouse model that spontaneously develops myocarditis with lower mortality than observed in previous HLA-DQ8 NOD mouse strains. Our strain was rendered murine MHC class I and II deficient using CRISPR/Cas9 technology, making it a genetically clean platform for dissecting CD4+ T cell-mediated myocarditis in the absence of classically selected CD8+ T cells. These mice are highly susceptible to myocarditis and acute heart failure following anti-PD-1 ICI-induced treatment. Additionally, anti-PD-1 administration accelerates skeletal muscle myositis. Using histology, flow cytometry, adoptive transfers, and RNA sequencing analyses, we performed a thorough characterization of cardiac and skeletal muscle T cells, identifying shared and unique characteristics of both populations. Taken together, this report details a mouse model with features of a rare, but highly lethal clinical presentation of overlapping myocarditis and myositis following ICI therapy. This study sheds light on underlying immunological mechanisms in ICI myocarditis and provides the basis for further detailed analyses of diagnostic and therapeutic strategies.
Collapse
Affiliation(s)
| | | | | | - Adel Misherghi
- The Jackson Laboratory, Bar Harbor, Maine, USA
- College of the Atlantic, Bar Harbor, Maine, USA
| | - Raheem Khadour
- The Jackson Laboratory, Bar Harbor, Maine, USA
- College of the Atlantic, Bar Harbor, Maine, USA
| | | | | | | | | | | | - Peter Rainer
- Medical University of Graz, Graz, 8053 Austria
- BioTechMed Graz, Graz, Austria
- BKH St. Johann in Tirol, 6380 St. Johann in Tirol, Austria
| | - Nadia Rosenthal
- The Jackson Laboratory, Bar Harbor, Maine, USA
- Imperial College London, London SW7 2AZ, UK
| | - Susanne Sattler
- Imperial College London, London SW7 2AZ, UK
- Medical University of Graz, Graz, 8053 Austria
| | | |
Collapse
|
5
|
Morales PN, Coons AN, Koopman AJ, Patel S, Chase PB, Parvatiyar MS, Pinto JR. Post-translational modifications of vertebrate striated muscle myosin heavy chains. Cytoskeleton (Hoboken) 2024. [PMID: 38587113 DOI: 10.1002/cm.21857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/06/2024] [Accepted: 03/25/2024] [Indexed: 04/09/2024]
Abstract
Post-translational modifications (PTMs) play a crucial role in regulating the function of many sarcomeric proteins, including myosin. Myosins comprise a family of motor proteins that play fundamental roles in cell motility in general and muscle contraction in particular. A myosin molecule consists of two myosin heavy chains (MyHCs) and two pairs of myosin light chains (MLCs); two MLCs are associated with the neck region of each MyHC's N-terminal head domain, while the two MyHC C-terminal tails form a coiled-coil that polymerizes with other MyHCs to form the thick filament backbone. Myosin undergoes extensive PTMs, and dysregulation of these PTMs may lead to abnormal muscle function and contribute to the development of myopathies and cardiovascular disorders. Recent studies have uncovered the significance of PTMs in regulating MyHC function and showed how these PTMs may provide additional modulation of contractile processes. Here, we discuss MyHC PTMs that have been biochemically and/or functionally studied in mammals' and rodents' striated muscle. We have identified hotspots or specific regions in three isoforms of myosin (MYH2, MYH6, and MYH7) where the prevalence of PTMs is more frequent and could potentially play a significant role in fine-tuning the activity of these proteins.
Collapse
Affiliation(s)
- Paula Nieto Morales
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Arianna N Coons
- Department of Biological Science, Florida State University, Tallahassee, Florida, USA
| | - Amelia J Koopman
- Department of Biological Science, Florida State University, Tallahassee, Florida, USA
| | - Sonu Patel
- Department of Health, Nutrition and Food Sciences, Florida State University, Tallahassee, Florida, USA
| | - P Bryant Chase
- Department of Biological Science, Florida State University, Tallahassee, Florida, USA
| | - Michelle S Parvatiyar
- Department of Health, Nutrition and Food Sciences, Florida State University, Tallahassee, Florida, USA
| | - Jose R Pinto
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| |
Collapse
|
6
|
Chapman EA, Li BH, Krichel B, Chan HJ, Buck KM, Roberts DS, Ge Y. Native Top-Down Mass Spectrometry for Characterizing Sarcomeric Proteins Directly from Cardiac Tissue Lysate. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:738-745. [PMID: 38422011 PMCID: PMC11098619 DOI: 10.1021/jasms.3c00430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Native top-down mass spectrometry (nTDMS) has emerged as a powerful structural biology tool that can localize post-translational modifications (PTMs), explore ligand-binding interactions, and elucidate the three-dimensional structure of proteins and protein complexes in the gas-phase. Fourier-transform ion cyclotron resonance (FTICR) MS offers distinct capabilities for nTDMS, owing to its ultrahigh resolving power, mass accuracy, and robust fragmentation techniques. Previous nTDMS studies using FTICR have mainly been applied to overexpressed recombinant proteins and protein complexes. Here, we report the first nTDMS study that directly analyzes human heart tissue lysate by direct infusion FTICR MS without prior chromatographic separation strategies. We have achieved comprehensive nTDMS characterization of cardiac contractile proteins that play critical roles in heart contraction and relaxation. Specifically, our results reveal structural insights into ventricular myosin light chain 2 (MLC-2v), ventricular myosin light chain 1 (MLC-1v), and alpha-tropomyosin (α-Tpm) in the sarcomere, the basic contractile unit of cardiac muscle. Furthermore, we verified the calcium (Ca2+) binding domain in MLC-2v. In summary, our nTDMS platform extends the application of FTICR MS to directly characterize the structure, PTMs, and metal-binding of endogenous proteins from heart tissue lysate without prior separation methods.
Collapse
Affiliation(s)
- Emily A. Chapman
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Brad H. Li
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Boris Krichel
- School of Life Sciences, University of Siegen, 57076, Germany
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Hsin-Ju Chan
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Kevin M. Buck
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - David S. Roberts
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
- Human Proteomics Program, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| |
Collapse
|
7
|
Sun H, He Z, Gao Y, Yang Y, Wang Y, Gu A, Xu J, Quan Y, Yang Y. Polyoxyethylene tallow amine and glyphosate exert different developmental toxicities on human pluripotent stem cells-derived heart organoid model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170675. [PMID: 38316312 DOI: 10.1016/j.scitotenv.2024.170675] [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: 12/06/2023] [Revised: 01/27/2024] [Accepted: 02/02/2024] [Indexed: 02/07/2024]
Abstract
The early stage of heart development is highly susceptible to various environmental factors. While the use of animal models has aided in identifying numerous environmental risk factors, the variability between species and the low throughput limit their translational potential. Recently, a type of self-assembling cardiac structures, known as human heart organoids (hHOs), exhibits a remarkable biological consistency with human heart. However, the feasibility of hHOs for assessing cardiac developmental risk factors remains unexplored. Here, we focused on the cardiac developmental effects of core components of Glyphosate-based herbicides (GBHs), the most widely used herbicides, to evaluate the reliability of hHOs for the prediction of possible cardiogenesis toxicity. GBHs have been proven toxic to cardiac development based on multiple animal models, with the mechanism remaining unknown. We found that polyoxyethylene tallow amine (POEA), the most common surfactant in GBHs formulations, played a dominant role in GBHs' heart developmental toxicity. Though there were a few differences in transcriptive features, hHOs exposed to sole POEA and combined POEA and Glyphosate would suffer from both disruption of heart contraction and disturbance of commitment in cardiomyocyte isoforms. By contrast, Glyphosate only caused mild epicardial hyperplasia. This study not only sheds light on the toxic mechanism of GBHs, but also serves as a methodological demonstration, showcasing its effectiveness in recognizing and evaluating environmental risk factors, and deciphering toxic mechanisms.
Collapse
Affiliation(s)
- Hao Sun
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing 211166, China
| | - Zhazheng He
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Yao Gao
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Yanhan Yang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing 211166, China
| | - Yachang Wang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing 211166, China
| | - Aihua Gu
- State Key Laboratory of Reproductive Medicine and Offspring Health, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Jin Xu
- State Key Laboratory of Reproductive Medicine and Offspring Health, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Yingyi Quan
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing 211166, China
| | - Yang Yang
- State Key Laboratory of Reproductive Medicine and Offspring Health, Nanjing Medical University, Nanjing 211166, China.
| |
Collapse
|
8
|
Hyodo T, Asano-Inami E, Ito S, Sugiyama M, Nawa A, Rahman ML, Hasan MN, Mihara Y, Lam VQ, Karnan S, Ota A, Tsuzuki S, Hamaguchi M, Hosokawa Y, Konishi H. Leucine zipper protein 1 (LUZP1) regulates the constriction velocity of the contractile ring during cytokinesis. FEBS J 2024; 291:927-944. [PMID: 38009294 DOI: 10.1111/febs.17017] [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: 01/18/2023] [Revised: 09/11/2023] [Accepted: 11/22/2023] [Indexed: 11/28/2023]
Abstract
There has been a great deal of research on cell division and its mechanisms; however, its processes still have many unknowns. To find novel proteins that regulate cell division, we performed the screening using siRNAs and/or the expression plasmid of the target genes and identified leucine zipper protein 1 (LUZP1). Recent studies have shown that LUZP1 interacts with various proteins and stabilizes the actin cytoskeleton; however, the function of LUZP1 in mitosis is not known. In this study, we found that LUZP1 colocalized with the chromosomal passenger complex (CPC) at the centromere in metaphase and at the central spindle in anaphase and that these LUZP1 localizations were regulated by CPC activity and kinesin family member 20A (KIF20A). Mass spectrometry analysis identified that LUZP1 interacted with death-associated protein kinase 3 (DAPK3), one regulator of the cleavage furrow ingression in cytokinesis. In addition, we found that LUZP1 also interacted with myosin light chain 9 (MYL9), a substrate of DAPK3, and comprehensively inhibited MYL9 phosphorylation by DAPK3. In line with a known role for MYL9 in the actin-myosin contraction, LUZP1 suppression accelerated the constriction velocity at the division plane in our time-lapse analysis. Our study indicates that LUZP1 is a novel regulator for cytokinesis that regulates the constriction velocity of the contractile ring.
Collapse
Affiliation(s)
- Toshinori Hyodo
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Eri Asano-Inami
- Department of Obstetrics and Gynecology Collaborative Research, Bell Research Center, Nagoya University Graduate School of Medicine, Japan
| | | | - Mai Sugiyama
- Department of Obstetrics and Gynecology Collaborative Research, Bell Research Center, Nagoya University Graduate School of Medicine, Japan
| | - Akihiro Nawa
- Department of Obstetrics and Gynecology Collaborative Research, Bell Research Center, Nagoya University Graduate School of Medicine, Japan
| | - Md Lutfur Rahman
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Muhammad Nazmul Hasan
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Yuko Mihara
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Vu Quang Lam
- Division of Hematology, Department of Internal Medicine, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Sivasundaram Karnan
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Akinobu Ota
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Shinobu Tsuzuki
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | | | - Yoshitaka Hosokawa
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| | - Hiroyuki Konishi
- Department of Biochemistry, Aichi Medical University School of Medicine, Nagakute, Japan
| |
Collapse
|
9
|
Rossler KJ, de Lange WJ, Mann MW, Aballo TJ, Melby JA, Zhang J, Kim G, Bayne EF, Zhu Y, Farrell ET, Kamp TJ, Ralphe JC, Ge Y. Lactate- and immunomagnetic-purified hiPSC-derived cardiomyocytes generate comparable engineered cardiac tissue constructs. JCI Insight 2024; 9:e172168. [PMID: 37988170 PMCID: PMC10906451 DOI: 10.1172/jci.insight.172168] [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: 05/09/2023] [Accepted: 11/17/2023] [Indexed: 11/23/2023] Open
Abstract
Three-dimensional engineered cardiac tissue (ECT) using purified human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) has emerged as an appealing model system for the study of human cardiac biology and disease. A recent study reported widely used metabolic (lactate) purification of monolayer hiPSC-CM cultures results in an ischemic cardiomyopathy-like phenotype compared with magnetic antibody-based cell sorting (MACS) purification, complicating the interpretation of studies using lactate-purified hiPSC-CMs. Herein, our objective was to determine if use of lactate relative to MACS-purified hiPSC-CMs affects the properties of resulting hiPSC-ECTs. Therefore, hiPSC-CMs were differentiated and purified using either lactate-based media or MACS. Global proteomics revealed that lactate-purified hiPSC-CMs displayed a differential phenotype over MACS hiPSC-CMs. hiPSC-CMs were then integrated into 3D hiPSC-ECTs and cultured for 4 weeks. Structurally, there was no significant difference in sarcomere length between lactate and MACS hiPSC-ECTs. Assessment of isometric twitch force and Ca2+ transient measurements revealed similar functional performance between purification methods. High-resolution mass spectrometry-based quantitative proteomics showed no significant difference in protein pathway expression or myofilament proteoforms. Taken together, this study demonstrates that lactate- and MACS-purified hiPSC-CMs generate ECTs with comparable structural, functional, and proteomic features, and it suggests that lactate purification does not result in an irreversible change in a hiPSC-CM phenotype.
Collapse
Affiliation(s)
- Kalina J. Rossler
- Molecular and Cellular Pharmacology Training Program
- Department of Cell and Regenerative Biology
| | | | | | - Timothy J. Aballo
- Molecular and Cellular Pharmacology Training Program
- Department of Cell and Regenerative Biology
| | | | | | | | | | - Yanlong Zhu
- Human Proteomics Program, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | | | - Timothy J. Kamp
- Department of Cell and Regenerative Biology
- Department of Medicine
| | | | - Ying Ge
- Department of Cell and Regenerative Biology
- Department of Chemistry, and
- Human Proteomics Program, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA
| |
Collapse
|
10
|
Mohran S, Kooiker K, Mahoney-Schaefer M, Mandrycky C, Kao K, Tu AY, Freeman J, Moussavi-Harami F, Geeves M, Regnier M. The biochemically defined super relaxed state of myosin-A paradox. J Biol Chem 2024; 300:105565. [PMID: 38103642 PMCID: PMC10819765 DOI: 10.1016/j.jbc.2023.105565] [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: 09/12/2023] [Revised: 11/06/2023] [Accepted: 12/06/2023] [Indexed: 12/19/2023] Open
Abstract
The biochemical SRX (super-relaxed) state of myosin has been defined as a low ATPase activity state. This state can conserve energy when the myosin is not recruited for muscle contraction. The SRX state has been correlated with a structurally defined ordered (versus disordered) state of muscle thick filaments. The two states may be linked via a common interacting head motif (IHM) where the two heads of heavy meromyosin (HMM), or myosin, fold back onto each other and form additional contacts with S2 and the thick filament. Experimental observations of the SRX, IHM, and the ordered form of thick filaments, however, do not always agree, and result in a series of unresolved paradoxes. To address these paradoxes, we have reexamined the biochemical measurements of the SRX state for porcine cardiac HMM. In our hands, the commonly employed mantATP displacement assay was unable to quantify the population of the SRX state with all data fitting very well by a single exponential. We further show that mavacamten inhibits the basal ATPases of both porcine ventricle HMM and S1 (Ki, 0.32 and 1.76 μM respectively) while dATP activates HMM cooperatively without any evidence of an SRX state. A combination of our experimental observations and theories suggests that the displacement of mantATP in purified proteins is not a reliable assay to quantify the SRX population. This means that while the structurally defined IHM and ordered thick filaments clearly exist, great care must be employed when using the mantATP displacement assay.
Collapse
Affiliation(s)
- Saffie Mohran
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA
| | - Kristina Kooiker
- Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA; Division of Cardiology, University of Washington, Seattle, Washington, USA
| | | | - Christian Mandrycky
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA
| | - Kerry Kao
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - An-Yue Tu
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA
| | - Jeremy Freeman
- Division of Cardiology, University of Washington, Seattle, Washington, USA
| | - Farid Moussavi-Harami
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA; Division of Cardiology, University of Washington, Seattle, Washington, USA
| | - Michael Geeves
- School of Biosciences, University of Kent, Canterbury, UK.
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA.
| |
Collapse
|
11
|
Tsuji-Tamura K, Ogawa M. FOXO1 promotes endothelial cell elongation and angiogenesis by up-regulating the phosphorylation of myosin light chain 2. Angiogenesis 2023; 26:523-545. [PMID: 37488325 DOI: 10.1007/s10456-023-09884-7] [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: 01/06/2023] [Accepted: 07/11/2023] [Indexed: 07/26/2023]
Abstract
The forkhead box O1 (FOXO1) is an important transcription factor related to proliferation, metabolism, and homeostasis, while the major phenotype of FOXO1-null mice is abnormal vascular morphology, such as vessel enlargement and dilation. In in vitro mouse embryonic stem cell (ESC)-differentiation system, Foxo1-/- vascular endothelial cells (ECs) fail to elongate, and mimic the abnormalities of FOXO1-deficiency in vivo. Here, we identified the PPP1R14C gene as the FOXO1 target genes responsible for elongating using transcriptome analyses in ESC-derived ECs (ESC-ECs), and found that the FOXO1-PPP1R14C-myosin light chain 2 (MLC2) axis is required for EC elongation during angiogenesis. MLC2 is phosphorylated by MLC kinase (MLCK) and dephosphorylated by MLC phosphatase (MLCP). PPP1R14C is an inhibitor of PP1, the catalytic subunit of MLCP. The abnormal morphology of Foxo1-/- ESC-ECs was associated with low level of PPP1R14C and loss of MLC2 phosphorylation, which were reversed by PPP1R14C-introduction. Knockdown of either FOXO1 or PPP1R14C suppressed vascular cord formation and reduced MLC2 phosphorylation in human ECs (HUVECs). The mouse and human PPP1R14C locus possesses an enhancer element containing conserved FOXO1-binding motifs. In vivo chemical inhibition of MLC2 phosphorylation caused dilated vascular structures in mouse embryos. Furthermore, foxo1 or ppp1r14c-knockdown zebrafish exhibited vascular malformations, which were also restored by PPP1R14C-introduction. Mechanistically, FOXO1 suppressed MLCP activity by up-regulating PPP1R14C expression, thereby promoting MLC2 phosphorylation and EC elongation, which are necessary for vascular development. Given the importance of MLC2 phosphorylation in cell morphogenesis, this study may provide novel insights into the role of FOXO1 in control of angiogenesis.
Collapse
Affiliation(s)
- Kiyomi Tsuji-Tamura
- Oral Biochemistry and Molecular Biology, Department of Oral Health Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-Ku, Sapporo, 060-8586, Japan.
| | - Minetaro Ogawa
- Department of Cell Differentiation, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-Ku, Kumamoto, 860-0811, Japan
| |
Collapse
|
12
|
Bayne EF, Rossler KJ, Gregorich ZR, Aballo TJ, Roberts DS, Chapman EA, Guo W, Palecek SP, Ralphe JC, Kamp TJ, Ge Y. Top-down proteomics of myosin light chain isoforms define chamber-specific expression in the human heart. J Mol Cell Cardiol 2023; 181:89-97. [PMID: 37327991 PMCID: PMC10528938 DOI: 10.1016/j.yjmcc.2023.06.003] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 05/27/2023] [Accepted: 06/13/2023] [Indexed: 06/18/2023]
Abstract
Myosin functions as the "molecular motor" of the sarcomere and generates the contractile force necessary for cardiac muscle contraction. Myosin light chains 1 and 2 (MLC-1 and -2) play important functional roles in regulating the structure of the hexameric myosin molecule. Each of these light chains has an 'atrial' and 'ventricular' isoform, so called because they are believed to exhibit chamber-restricted expression in the heart. However, recently the chamber-specific expression of MLC isoforms in the human heart has been questioned. Herein, we analyzed the expression of MLC-1 and -2 atrial and ventricular isoforms in each of the four cardiac chambers in adult non-failing donor hearts using top-down mass spectrometry (MS)-based proteomics. Strikingly, we detected an isoform thought to be ventricular, MLC-2v (gene: MYL2), in the atria and confirmed the protein sequence using tandem MS (MS/MS). For the first time, a putative deamidation post-translation modification (PTM) located on MLC-2v in atrial tissue was localized to amino acid N13. MLC-1v (MYL3) and MLC-2a (MYL7) were the only MLC isoforms exhibiting chamber-restricted expression patterns across all donor hearts. Importantly, our results unambiguously show that MLC-1v, not MLC-2v, is ventricle-specific in adult human hearts. Moreover, we found elevated MLC-2 phosphorylation in male hearts compared to female hearts across each cardiac chamber. Overall, top-down proteomics allowed an unbiased analysis of MLC isoform expression throughout the human heart, uncovering previously unexpected isoform expression patterns and PTMs.
Collapse
Affiliation(s)
- Elizabeth F Bayne
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Kalina J Rossler
- Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Zachery R Gregorich
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Timothy J Aballo
- Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - David S Roberts
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Emily A Chapman
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Wei Guo
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sean P Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - J Carter Ralphe
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Timothy J Kamp
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705, USA; Human Proteomics Program, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA.
| |
Collapse
|
13
|
Román‐Carrasco P, Klug C, Hemmer W, Focke‐Tejkl M, Raith M, Grosinger I, Stoll P, Quirce S, Sanchez‐Jareño M, Martínez‐Blanco M, Molina E, Somoza V, Lieder B, Marin Z, Nöbauer K, Hummel K, Razzazi‐Fazeli E, Swoboda I. Bos d 13, A Novel Heat-Stable Beef Allergen. Mol Nutr Food Res 2023; 67:e2200601. [PMID: 37173826 PMCID: PMC10909433 DOI: 10.1002/mnfr.202200601] [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: 09/06/2022] [Revised: 03/24/2023] [Indexed: 05/15/2023]
Abstract
SCOPE Red meat, a staple food of Western diets, can also induce IgE-mediated allergic reactions. Yet, apart from the heat-labile protein serum albumin and the carbohydrate α-Gal, the molecules causing allergic reactions to red meat remain unknown. METHODS AND RESULTS IgE reactivity profiles of beef-sensitized individuals are analyzed by IgE-immunoblotting with protein extracts from raw and cooked beef. Two IgE-reactive proteins are identified by peptide mass fingerprinting as myosinlight chain 1 (MYL1) and myosin light chain 3 (MYL3) in cooked beef extract and are designated Bos d 13 isoallergens. MYL1 and MYL3 are produced recombinantly in Escherichia coli. ELISAs proved their IgE reactivity and circular dichroism analysis showed that they represent folded molecules with remarkable thermal stability. In vitro gastrointestinal digestion experiments showed the higher stability of rMYL1 as compared to rMYL3. Exposure of a monolayer of Caco-2 cells to rMYL1 indicated that the molecule is able to cross intestinal epithelial cells without disturbing the integrity of the tight junctions, suggesting the sensitizing capacity of MYL1. CONCLUSION MYLs are identified as novel heat-stable bovine meat allergens.
Collapse
Affiliation(s)
- Patricia Román‐Carrasco
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
| | - Christoph Klug
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
- Present address: MacroArray Diagnostics GmbHVienna1230Austria
| | | | - Margarete Focke‐Tejkl
- Division of ImmunopathologyDepartment of Pathophysiology and Allergy ResearchCenter for PathophysiologyInfectiology and ImmunologyMedical University of ViennaVienna1090Austria
| | - Marianne Raith
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
| | - Isabella Grosinger
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
| | - Peter Stoll
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
| | - Santiago Quirce
- Department of AllergyLa Paz University Hospital, IdiPAZMadrid28046Spain
| | | | - Mónica Martínez‐Blanco
- Instituto de Investigación en Ciencias de la Alimentación (CIAL, CSIC‐UAM)Madrid28049Spain
| | - Elena Molina
- Instituto de Investigación en Ciencias de la Alimentación (CIAL, CSIC‐UAM)Madrid28049Spain
| | - Veronika Somoza
- Department of Physiological ChemistryFaculty of ChemistryUniversity of ViennaVienna1090Austria
- Leibniz Institute for Food Systems BiologyTechnical University Munich85354MunichGermany
| | - Barbara Lieder
- Department of Physiological ChemistryFaculty of ChemistryUniversity of ViennaVienna1090Austria
| | - Zana Marin
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
| | - Katharina Nöbauer
- VetCore Facility for ResearchUniversity of Veterinary MedicineVienna1210Austria
| | - Karin Hummel
- VetCore Facility for ResearchUniversity of Veterinary MedicineVienna1210Austria
| | | | - Ines Swoboda
- Biotechnology SectionFH Campus WienCampus Vienna BiocenterUniversity of Applied SciencesVienna1100Austria
- Division of ImmunopathologyDepartment of Pathophysiology and Allergy ResearchCenter for PathophysiologyInfectiology and ImmunologyMedical University of ViennaVienna1090Austria
| |
Collapse
|
14
|
Gerzen OP, Votinova VO, Potoskueva IK, Tzybina AE, Nikitina LV. Direct Effects of Toxic Divalent Cations on Contractile Proteins with Implications for the Heart: Unraveling Mechanisms of Dysfunction. Int J Mol Sci 2023; 24:10579. [PMID: 37445756 DOI: 10.3390/ijms241310579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 06/19/2023] [Accepted: 06/22/2023] [Indexed: 07/15/2023] Open
Abstract
The binding of calcium and magnesium ions to proteins is crucial for regulating heart contraction. However, other divalent cations, including xenobiotics, can accumulate in the myocardium and enter cardiomyocytes, where they can bind to proteins. In this article, we summarized the impact of these cations on myosin ATPase activity and EF-hand proteins, with special attention given to toxic cations. Optimal binding to EF-hand proteins occurs at an ionic radius close to that of Mg2+ and Ca2+. In skeletal Troponin C, Cd2+, Sr2+, Pb2+, Mn2+, Co2+, Ni2+, Ba2+, Mg2+, Zn2+, and trivalent lanthanides can substitute for Ca2+. As myosin ATPase is not a specific MgATPase, Ca2+, Fe2+, Mn2+, Ni2+, and Sr2+ could support myosin ATPase activity. On the other hand, Zn2+ and Cu2 significantly inhibit ATPase activity. The affinity to various divalent cations depends on certain proteins or their isoforms and can alter with amino acid substitution and post-translational modification. Cardiac EF-hand proteins and the myosin ATP-binding pocket are potential molecular targets for toxic cations, which could significantly alter the mechanical characteristics of the heart muscle at the molecular level.
Collapse
Affiliation(s)
- Oksana P Gerzen
- Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences, 620049 Ekaterinburg, Russia
| | - Veronika O Votinova
- Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences, 620049 Ekaterinburg, Russia
| | - Iulia K Potoskueva
- Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences, 620049 Ekaterinburg, Russia
| | - Alyona E Tzybina
- Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences, 620049 Ekaterinburg, Russia
| | - Larisa V Nikitina
- Institute of Immunology and Physiology of the Ural Branch of the Russian Academy of Sciences, 620049 Ekaterinburg, Russia
| |
Collapse
|
15
|
Rossler KJ, de Lange WJ, Mann MW, Aballo TJ, Melby JA, Zhang J, Kim G, Bayne EF, Zhu Y, Farrell ET, Kamp TJ, Ralphe JC, Ge Y. Lactate and Immunomagnetic-purified iPSC-derived Cardiomyocytes Generate Comparable Engineered Cardiac Tissue Constructs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.05.539642. [PMID: 37205556 PMCID: PMC10187273 DOI: 10.1101/2023.05.05.539642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Three-dimensional engineered cardiac tissue (ECT) using purified human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) has emerged as an appealing model system for the study of human cardiac biology and disease. A recent study reported widely-used metabolic (lactate) purification of monolayer hiPSC-CM cultures results in an ischemic cardiomyopathy-like phenotype compared to magnetic antibody-based cell sorting (MACS) purification, complicating the interpretation of studies using lactate-purified hiPSC-CMs. Herein, our objective was to determine if use of lactate relative to MACs-purified hiPSC-CMs impacts the properties of resulting hiPSC-ECTs. Therefore, hiPSC-CMs were differentiated and purified using either lactate-based media or MACS. After purification, hiPSC-CMs were combined with hiPSC-cardiac fibroblasts to create 3D hiPSC-ECT constructs maintained in culture for four weeks. There were no structural differences observed, and there was no significant difference in sarcomere length between lactate and MACS hiPSC-ECTs. Assessment of isometric twitch force, Ca 2+ transients, and β-adrenergic response revealed similar functional performance between purification methods. High-resolution mass spectrometry (MS)-based quantitative proteomics showed no significant difference in any protein pathway expression or myofilament proteoforms. Taken together, this study demonstrates lactate- and MACS-purified hiPSC-CMs generate ECTs with comparable molecular and functional properties, and suggests lactate purification does not result in an irreversible change in hiPSC-CM phenotype.
Collapse
|
16
|
Bayne EF, Rossler KJ, Gregorich ZR, Aballo TJ, Roberts DS, Chapman EA, Guo W, Ralphe JC, Kamp TJ, Ge Y. Top-down Proteomics of Myosin Light Chain Isoforms Define Chamber-Specific Expression in the Human Heart. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.26.525767. [PMID: 36747670 PMCID: PMC9900887 DOI: 10.1101/2023.01.26.525767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Myosin functions as the "molecular motor" of the sarcomere and generates the contractile force necessary for cardiac muscle contraction. Myosin light chains 1 and 2 (MLC-1 and -2) play important functional roles in regulating the structure of the hexameric myosin molecule. Each of these light chains has an "atrial" and "ventricular" isoform, so called because they are believed to exhibit chamber-restricted expression in the heart. However, recently the chamber-specific expression of MLC isoforms in the human heart has been questioned. Herein, we analyzed the expression of MLC-1 and -2 atrial and ventricular isoforms in each of the four cardiac chambers in adult non-failing donor hearts using top-down mass spectrometry (MS)-based proteomics. Strikingly, we detected an isoform thought to be ventricular, MLC-2v, in the atria and confirmed the protein sequence using tandem MS (MS/MS). For the first time, a putative deamidation post-translation modification (PTM) located on MLC-2v in atrial tissue was localized to amino acid N13. MLC-1v and MLC-2a were the only MLC isoforms exhibiting chamber-restricted expression patterns across all donor hearts. Importantly, our results unambiguously show that MLC-1v, not MLC-2v, is ventricle-specific in adult human hearts. Overall, top-down proteomics allowed us an unbiased analysis of MLC isoform expression throughout the human heart, uncovering previously unexpected isoform expression patterns and PTMs.
Collapse
|
17
|
Dowling P, Gargan S, Swandulla D, Ohlendieck K. Fiber-Type Shifting in Sarcopenia of Old Age: Proteomic Profiling of the Contractile Apparatus of Skeletal Muscles. Int J Mol Sci 2023; 24:ijms24032415. [PMID: 36768735 PMCID: PMC9916839 DOI: 10.3390/ijms24032415] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 01/28/2023] Open
Abstract
The progressive loss of skeletal muscle mass and concomitant reduction in contractile strength plays a central role in frailty syndrome. Age-related neuronal impairments are closely associated with sarcopenia in the elderly, which is characterized by severe muscular atrophy that can considerably lessen the overall quality of life at old age. Mass-spectrometry-based proteomic surveys of senescent human skeletal muscles, as well as animal models of sarcopenia, have decisively improved our understanding of the molecular and cellular consequences of muscular atrophy and associated fiber-type shifting during aging. This review outlines the mass spectrometric identification of proteome-wide changes in atrophying skeletal muscles, with a focus on contractile proteins as potential markers of changes in fiber-type distribution patterns. The observed trend of fast-to-slow transitions in individual human skeletal muscles during the aging process is most likely linked to a preferential susceptibility of fast-twitching muscle fibers to muscular atrophy. Studies with senescent animal models, including mostly aged rodent skeletal muscles, have confirmed fiber-type shifting. The proteomic analysis of fast versus slow isoforms of key contractile proteins, such as myosin heavy chains, myosin light chains, actins, troponins and tropomyosins, suggests them as suitable bioanalytical tools of fiber-type transitions during aging.
Collapse
Affiliation(s)
- Paul Dowling
- Department of Biology, Maynooth University, National University of Ireland, W23 F2H6 Maynooth, Co. Kildare, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, W23 F2H6 Maynooth, Co. Kildare, Ireland
| | - Stephen Gargan
- Department of Biology, Maynooth University, National University of Ireland, W23 F2H6 Maynooth, Co. Kildare, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, W23 F2H6 Maynooth, Co. Kildare, Ireland
| | - Dieter Swandulla
- Institute of Physiology, University of Bonn, D53115 Bonn, Germany
| | - Kay Ohlendieck
- Department of Biology, Maynooth University, National University of Ireland, W23 F2H6 Maynooth, Co. Kildare, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, W23 F2H6 Maynooth, Co. Kildare, Ireland
- Correspondence: ; Tel.: +353-1-7083842
| |
Collapse
|
18
|
Johnson LG, Zhai C, Reever LM, Prusa KJ, Nair MN, Huff-Lonergan E, Lonergan SM. Characterizing the sarcoplasmic proteome of aged pork chops classified by purge loss. J Anim Sci 2023; 101:7031059. [PMID: 36751720 PMCID: PMC9994594 DOI: 10.1093/jas/skad046] [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: 11/30/2022] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
Unpredictable variation in quality, including fresh pork water-holding capacity, remains challenging to pork processors and customers. Defining the diverse factors that influence fresh pork water-holding capacity is necessary to make progress in refining pork quality prediction methods. The objective was to utilize liquid chromatography and mass spectrometry coupled with tandem mass tag (TMT) multiplexing to evaluate the sarcoplasmic proteome of aged pork loins classified by purge loss. Fresh commercial pork loins were collected, aged 12 or 14 d postmortem, and pork quality and sensory attributes were evaluated. Chops were classified into Low (N = 27, average purge = 0.33%), Intermediate (N = 27, average purge = 0.72%), or High (N = 27, average purge = 1.19%) chop purge groups. Proteins soluble in a low-ionic strength buffer were extracted, digested with trypsin, labeled with 11-plex isobaric TMT reagents, and detected using a Q-Exactive Mass Spectrometer. Between the Low and High purge groups, 40 proteins were differentially (P < 0.05) abundant. The Low purge group had a greater abundance of proteins classified as structural and contractile, sarcoplasmic reticulum and calcium regulating, chaperone, and citric acid cycle enzymes than the High purge group. The presence of myofibrillar proteins in the aged sarcoplasmic proteome is likely due to postmortem degradation. These observations support our hypothesis that pork chops with low purge have a greater abundance of structural proteins in the soluble protein fraction. Together, these and other proteins in the aged sarcoplasmic proteome may be biomarkers of pork water-holding capacity. Additional research should establish the utility of these proteins as biomarkers early postmortem and over subsequent aging periods.
Collapse
Affiliation(s)
- Logan G Johnson
- Department of Animal Science, Iowa State University, Ames, Iowa 50011, USA
| | - Chaoyu Zhai
- Department of Animal Science, University of Connecticut, Storrs, Connecticut 06269-4040, USA
| | - Leah M Reever
- Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011, USA
| | - Kenneth J Prusa
- Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011, USA
| | - Mahesh N Nair
- Department of Animal Sciences, Colorado State University, Fort Collins, Colorado 80523, USA
| | | | - Steven M Lonergan
- Department of Animal Science, Iowa State University, Ames, Iowa 50011, USA
| |
Collapse
|
19
|
Johnson LG, Zhai C, Steadham EM, Reever LM, Prusa KJ, Nair MN, Huff-Lonergan E, Lonergan SM. Distinct myofibrillar sub-proteomic profiles are associated with the instrumental texture of aged pork loin. J Anim Sci 2023; 101:skad327. [PMID: 37751382 PMCID: PMC10629443 DOI: 10.1093/jas/skad327] [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: 08/11/2023] [Accepted: 09/22/2023] [Indexed: 09/28/2023] Open
Abstract
Fresh pork tenderness contributes to consumer satisfaction with the eating experience. Postmortem proteolysis of proteins within and between myofibrils has been closely linked with pork tenderness development. A clear understanding of the molecular features associated with pork tenderness development will provide additional targets and open the door to new solutions to improve and make pork tenderness development more consistent. Therefore, the objective was to utilize liquid chromatography and mass spectrometry with tandem mass tag (TMT) multiplexing to evaluate myofibrillar sub-proteome differences between pork chops of different instrumental star probe values. Pork loins (N = 120) were collected from a commercial harvest facility at 24 h postmortem. Quality and sensory attributes were evaluated at 24 h postmortem and after ~2 weeks of postmortem aging. Pork chops were grouped into 4 groups based on instrumental star probe value (group A,x¯ = 4.23 kg, 3.43 to 4.55 kg; group B,x¯ = 4.79 kg, 4.66 to 5.00 kg; group C,x¯ = 5.43 kg, 5.20 to 5.64 kg; group D,x¯ = 6.21 kg, 5.70 to 7.41 kg; n = 25 per group). Myofibrillar proteins from the samples aged ~2 wk were fractionated, washed, and solubilized in 8.3 M urea, 2 M thiourea, and 1% dithiothreitol. Proteins were digested with trypsin, labeled with 11-plex isobaric TMT reagents, and identified and quantified using a Q-Exactive Mass Spectrometer. Between groups A and D, 54 protein groups were differentially abundant (adjusted P < 0.05). Group A had a greater abundance of proteins related to the thick and thin filament and a lesser abundance of Z-line-associated proteins and metabolic enzymes than group D chops. These data highlight that distinct myofibrillar sub-proteomes are associated with pork chops of different tenderness values. Future research should evaluate changes immediately and earlier postmortem to further elucidate myofibrillar sub-proteome differences over the postmortem aging period.
Collapse
Affiliation(s)
- Logan G Johnson
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA
| | - Chaoyu Zhai
- Department of Animal Science, University of Connecticut, Storrs, CT 06269-4040, USA
| | - Edward M Steadham
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA
| | - Leah M Reever
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Kenneth J Prusa
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Mahesh N Nair
- Department of Animal Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | | | - Steven M Lonergan
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA
| |
Collapse
|
20
|
Eaton DM, Martin TG, Kasa M, Djalinac N, Ljubojevic-Holzer S, Von Lewinski D, Pöttler M, Kampaengsri T, Krumphuber A, Scharer K, Maechler H, Zirlik A, McKinsey TA, Kirk JA, Houser SR, Rainer PP, Wallner M. HDAC Inhibition Regulates Cardiac Function by Increasing Myofilament Calcium Sensitivity and Decreasing Diastolic Tension. Pharmaceutics 2022; 14:pharmaceutics14071509. [PMID: 35890404 PMCID: PMC9323146 DOI: 10.3390/pharmaceutics14071509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 01/09/2023] Open
Abstract
We recently established a large animal model that recapitulates key clinical features of heart failure with preserved ejection fraction (HFpEF) and tested the effects of the pan-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). SAHA reversed and prevented the development of cardiopulmonary impairment. This study evaluated the effects of SAHA at the level of cardiomyocyte and contractile protein function to understand how it modulates cardiac function. Both isolated adult feline ventricular cardiomyocytes (AFVM) and left ventricle (LV) trabeculae isolated from non-failing donors were treated with SAHA or vehicle before recording functional data. Skinned myocytes were isolated from AFVM and human trabeculae to assess myofilament function. SAHA-treated AFVM had increased contractility and improved relaxation kinetics but no difference in peak calcium transients, with increased calcium sensitivity and decreased passive stiffness of myofilaments. Mass spectrometry analysis revealed increased acetylation of the myosin regulatory light chain with SAHA treatment. SAHA-treated human trabeculae had decreased diastolic tension and increased developed force. Myofilaments isolated from human trabeculae had increased calcium sensitivity and decreased passive stiffness. These findings suggest that SAHA has an important role in the direct control of cardiac function at the level of the cardiomyocyte and myofilament by increasing myofilament calcium sensitivity and reducing diastolic tension.
Collapse
Affiliation(s)
- Deborah M. Eaton
- Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA; (D.M.E.); (S.R.H.)
- Penn Cardiovascular Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Thomas G. Martin
- Department of Cell and Molecular Physiology, Loyola University Chicago Stritch School of Medicine, Chicago, IL 60153, USA; (T.G.M.); (T.K.); (J.A.K.)
| | - Michael Kasa
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Natasa Djalinac
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Senka Ljubojevic-Holzer
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Dirk Von Lewinski
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Maria Pöttler
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Theerachat Kampaengsri
- Department of Cell and Molecular Physiology, Loyola University Chicago Stritch School of Medicine, Chicago, IL 60153, USA; (T.G.M.); (T.K.); (J.A.K.)
| | - Andreas Krumphuber
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Katharina Scharer
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Heinrich Maechler
- Department of Cardiothoracic Surgery, Medical University of Graz, 8036 Graz, Austria;
| | - Andreas Zirlik
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
| | - Timothy A. McKinsey
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jonathan A. Kirk
- Department of Cell and Molecular Physiology, Loyola University Chicago Stritch School of Medicine, Chicago, IL 60153, USA; (T.G.M.); (T.K.); (J.A.K.)
| | - Steven R. Houser
- Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA; (D.M.E.); (S.R.H.)
| | - Peter P. Rainer
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
- BioTechMed Graz, 8010 Graz, Austria
| | - Markus Wallner
- Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA; (D.M.E.); (S.R.H.)
- Division of Cardiology, Medical University of Graz, 8036 Graz, Austria; (M.K.); (N.D.); (S.L.-H.); (D.V.L.); (M.P.); (A.K.); (K.S.); (A.Z.); (P.P.R.)
- Correspondence:
| |
Collapse
|
21
|
Fu X, Matsui T, Funaba M. Enhancement of vitamin C-induced myogenesis by inhibition of extracellular signal-regulated kinase (ERK) 1/2 pathway. Biochem Biophys Res Commun 2022; 612:57-62. [DOI: 10.1016/j.bbrc.2022.04.103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 04/15/2022] [Accepted: 04/22/2022] [Indexed: 11/02/2022]
|
22
|
Mechanisms of the modulation of actin-myosin interactions by A1-type myosin light chains. Biochim Biophys Acta Gen Subj 2022; 1866:130132. [PMID: 35307509 DOI: 10.1016/j.bbagen.2022.130132] [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: 12/05/2021] [Revised: 03/04/2022] [Accepted: 03/13/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND The interaction of N-terminal extension of the myosin A1 essential light chain (A1 ELC) with actin is receiving increasing attention as a target in utilizing synthetic A1 ELC N-terminal-derived peptides in cardiac dysfunction therapy. METHODS To elucidate the mechanism by which these peptides regulate actin-myosin interaction, here we have investigated their effects on the myosin subfragment 1 (S1)-induced polymerization of G-actin. RESULTS The MLCFpep and MLCSpep peptides spanning the 3-12 of A1 ELC sequences from fast and slow skeletal muscle, respectively, increased the rate of actin polymerization not only by S1(A2) but also the rate of S1(A1)-induced actin polymerization, suggesting that they did not interfere with the direct binding of A1 ELC with actin. The efficiency of actin polymerization in the presence of the N-terminal ELC peptides depended on their sequence. Substitution of aspartic acid for neutral asparagine at position 5 of MLCFpep dramatically enhanced its ability to stimulate S1-induced polymerization and enabled it to initiate polymerization of G-actin in the absence of S1. CONCLUSIONS These and other results presented in this work suggest that the modulation of myosin motor activity by N-terminal ELC peptides is exerted through a change in actin filament conformation rather than through blocking the A1 ELC-actin interaction. GENERAL SIGNIFICANCE The results imply the possibility of enhancing therapeutic effects of these peptides by modifications of their sequence.
Collapse
|
23
|
The Oxidative Balance Orchestrates the Main Keystones of the Functional Activity of Cardiomyocytes. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:7714542. [PMID: 35047109 PMCID: PMC8763515 DOI: 10.1155/2022/7714542] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 11/03/2021] [Accepted: 12/15/2021] [Indexed: 12/11/2022]
Abstract
This review is aimed at providing an overview of the key hallmarks of cardiomyocytes in physiological and pathological conditions. The main feature of cardiac tissue is the force generation through contraction. This process requires a conspicuous energy demand and therefore an active metabolism. The cardiac tissue is rich of mitochondria, the powerhouses in cells. These organelles, producing ATP, are also the main sources of ROS whose altered handling can cause their accumulation and therefore triggers detrimental effects on mitochondria themselves and other cell components thus leading to apoptosis and cardiac diseases. This review highlights the metabolic aspects of cardiomyocytes and wanders through the main systems of these cells: (a) the unique structural organization (such as different protein complexes represented by contractile, regulatory, and structural proteins); (b) the homeostasis of intracellular Ca2+ that represents a crucial ion for cardiac functions and E-C coupling; and (c) the balance of Zn2+, an ion with a crucial impact on the cardiovascular system. Although each system seems to be independent and finely controlled, the contractile proteins, intracellular Ca2+ homeostasis, and intracellular Zn2+ signals are strongly linked to each other by the intracellular ROS management in a fascinating way to form a "functional tetrad" which ensures the proper functioning of the myocardium. Nevertheless, if ROS balance is not properly handled, one or more of these components could be altered resulting in deleterious effects leading to an unbalance of this "tetrad" and promoting cardiovascular diseases. In conclusion, this "functional tetrad" is proposed as a complex network that communicates continuously in the cardiomyocytes and can drive the switch from physiological to pathological conditions in the heart.
Collapse
|
24
|
Molecular basis of force-pCa relation in MYL2 cardiomyopathy mice: Role of the super-relaxed state of myosin. Proc Natl Acad Sci U S A 2022; 119:2110328119. [PMID: 35177471 PMCID: PMC8872785 DOI: 10.1073/pnas.2110328119] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2022] [Indexed: 01/22/2023] Open
Abstract
Many forms of cardiomyopathy manifest with changes in sarcomeric structure, function, and energetics. We used small-angle X-ray diffraction and myosin super-relaxed (SRX) state approaches to investigate the mechanisms underlying the clinical phenotypes associated with HCM-related D166V (aspartate-to-valine) and DCM-linked D94A (aspartate-to-alanine) mutations in the cardiac myosin RLC (MYL2 gene). Modulation of myosin function through dysregulation of the SRX state was closely coupled with structural rearrangements and the Ca2+ dependence of force development in HCM–D166V mice. The DCM–D94A model favored the SRX state without altering structure/force–pCa relationships. Understanding the regulation of SRX ↔ DRX equilibrium in the normal heart and how it is changed in heart disease may advance future therapeutics of patients suffering from the mutated MYL2 gene. In this study, we investigated the role of the super-relaxed (SRX) state of myosin in the structure–function relationship of sarcomeres in the hearts of mouse models of cardiomyopathy-bearing mutations in the human ventricular regulatory light chain (RLC, MYL2 gene). Skinned papillary muscles from hypertrophic (HCM–D166V) and dilated (DCM–D94A) cardiomyopathy models were subjected to small-angle X-ray diffraction simultaneously with isometric force measurements to obtain the interfilament lattice spacing and equatorial intensity ratios (I11/I10) together with the force-pCa relationship over a full range of [Ca2+] and at a sarcomere length of 2.1 μm. In parallel, we studied the effect of mutations on the ATP-dependent myosin energetic states. Compared with wild-type (WT) and DCM–D94A mice, HCM–D166V significantly increased the Ca2+ sensitivity of force and left shifted the I11/I10-pCa relationship, indicating an apparent movement of HCM–D166V cross-bridges closer to actin-containing thin filaments, thereby allowing for their premature Ca2+ activation. The HCM–D166V model also disrupted the SRX state and promoted an SRX-to-DRX (super-relaxed to disordered relaxed) transition that correlated with an HCM-linked phenotype of hypercontractility. While this dysregulation of SRX ↔ DRX equilibrium was consistent with repositioning of myosin motors closer to the thin filaments and with increased force-pCa dependence for HCM–D166V, the DCM–D94A model favored the energy-conserving SRX state, but the structure/function–pCa data were similar to WT. Our results suggest that the mutation-induced redistribution of myosin energetic states is one of the key mechanisms contributing to the development of complex clinical phenotypes associated with human HCM–D166V and DCM–D94A mutations.
Collapse
|
25
|
Zhang Q, Yu Y, Luo Z, Xiang J, Li F. Comparison of Gene Expression Between Resistant and Susceptible Families Against VP AHPND and Identification of Biomarkers Used for Resistance Evaluation in Litopenaeus vannamei. Front Genet 2021; 12:772442. [PMID: 34899859 PMCID: PMC8662381 DOI: 10.3389/fgene.2021.772442] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/01/2021] [Indexed: 11/13/2022] Open
Abstract
Acute hepatopancreatic necrosis disease (AHPND) has caused a heavy loss to shrimp aquaculture since its outbreak. Vibrio parahaemolyticus (VPAHPND) is regarded as one of the main pathogens that caused AHPND in the Pacific white shrimp Litopenaeus vannamei. In order to learn more about the mechanism of resistance to AHPND, the resistant and susceptible shrimp families were obtained through genetic breeding, and comparative transcriptome approach was used to analyze the gene expression patterns between resistant and susceptible families. A total of 95 families were subjected to VPAHPND challenge test, and significant variations in the resistance of these families were observed. Three pairs of resistant and susceptible families were selected for transcriptome sequencing. A total of 489 differentially expressed genes (DEGs) that presented in at least two pairwise comparisons were screened, including 196 DEGs highly expressed in the susceptible families and 293 DEGs in the resistant families. Among these DEGs, 16 genes demonstrated significant difference in all three pairwise comparisons. Gene set enrichment analysis (GSEA) of all 27,331 expressed genes indicated that some energy metabolism processes were enriched in the resistant families, while signal transduction and immune system were enriched in the susceptible families. A total of 32 DEGs were further confirmed in the offspring of the detected families, among which 19 genes were successfully verified. The identified genes in this study will be useful for clarifying the genetic mechanism of shrimp resistance against Vibrio and will further provide molecular markers for evaluating the disease resistance of shrimp in the breeding program.
Collapse
Affiliation(s)
- Qian Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yang Yu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Zheng Luo
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jianhai Xiang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Fuhua Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.,Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China.,The Innovation of Seed Design, Chinese Academy of Sciences, Wuhan, China
| |
Collapse
|
26
|
You Y, Liu T, Shen J. Research progress in myosin light chain 9 in malignant tumors. ZHONG NAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF CENTRAL SOUTH UNIVERSITY. MEDICAL SCIENCES 2021; 46:1153-1158. [PMID: 34911847 PMCID: PMC10930228 DOI: 10.11817/j.issn.1672-7347.2021.200814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Indexed: 11/03/2022]
Abstract
Myosin light chain 9 (MYL9) is a regulatory light chain of myosin, which plays an important role in various biological processes including cell contraction, proliferation and invasion. MYL9 expresses abnormally in several malignancies including lung cancer, breast cancer, prostate cancer, malignant melanoma and others, which is closely related to the poor prognosis, but the clinical significance for its expression varies with different types of cancer tissues. Further elucidating the molecular mechanism of MYL9 in various types of malignant tumor metastasis is of great significance for cancer prevention and treatment. At the same time, as a molecular marker and potential target, MYL9 may have great clinical value in the early diagnosis, prognosis prediction, and targeted treatment of malignant tumors.
Collapse
Affiliation(s)
- Yimeng You
- Fujian Institute of Hematology; Fujian Provincial Key Laboratory on Hematology; Department of Hematology, Union Hospital Affiliated to Fujian Medical University, Fuzhou 350001, China.
| | - Tingbo Liu
- Fujian Institute of Hematology; Fujian Provincial Key Laboratory on Hematology; Department of Hematology, Union Hospital Affiliated to Fujian Medical University, Fuzhou 350001, China
| | - Jianzhen Shen
- Fujian Institute of Hematology; Fujian Provincial Key Laboratory on Hematology; Department of Hematology, Union Hospital Affiliated to Fujian Medical University, Fuzhou 350001, China.
| |
Collapse
|
27
|
Banaszkiewicz M, Olejnik A, Krzywonos-Zawadzka A, Hałucha K, Bil-Lula I. Expression of atrial‑fetal light chains in cultured human cardiomyocytes after chemical ischemia‑reperfusion injury. Mol Med Rep 2021; 24:770. [PMID: 34490485 PMCID: PMC8430302 DOI: 10.3892/mmr.2021.12410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/19/2021] [Indexed: 11/19/2022] Open
Abstract
Atrial light chains (ALC1) are naturally present in adult heart atria, while ventricular light chains (VLC1) are predominant in ventricles. Degradation of VLC1 and re-expression of ALC1 in heart ventricles are associated with heart disorders in response to pressure overload. The aim of the current study was to investigate changes in myosin light chain expression after simulated ischemia and simulated reperfusion (sI/sR). Human cardiomyocytes (HCM) isolated from adult heart ventricles were subjected to chemical ischemia. The control group was maintained under aerobic conditions. Myocyte injury was determined by testing lactate dehydrogenase (LDH) activity. The gene expression of ALC1, VLC1 and MMP-2 were assessed by reverse transcription-quatitive PCR. Additionally, protein synthesis was measured using ELISA kits and MMP-2 activity was measured by zymography. The results revealed that LDH activity was increased in sI/sR cell-conditioned medium (P=0.02), confirming the ischemic damage of HCM. ALC1 gene expression and content in HCM were also increased in the sI/sR group (P=0.03 and P<0.001, respectively), while VLC1 gene expression after sI/sR was decreased (P=0.008). Furthermore, MMP-2 gene expression and synthesis were lower in the sI/sR group when compared with the aerobic control group (P<0.001 and P=0.03, respectively). MMP-2 activity was also increased in sI/sR cell-conditioned medium (P=0.006). In conclusion, sI/sR treatment led to increased ALC1 and decreased VLC1 expression in ventricular cardiomyocytes, which may constitute an adaptive mechanism to altered conditions and contribute to the improvement of heart function.
Collapse
Affiliation(s)
- Marta Banaszkiewicz
- Division of Clinical Chemistry and Laboratory Haematology, Department of Medical Laboratory Diagnostics, Faculty of Pharmacy, Wroclaw Medical University, 50‑556 Wroclaw, Poland
| | - Agnieszka Olejnik
- Division of Clinical Chemistry and Laboratory Haematology, Department of Medical Laboratory Diagnostics, Faculty of Pharmacy, Wroclaw Medical University, 50‑556 Wroclaw, Poland
| | - Anna Krzywonos-Zawadzka
- Division of Clinical Chemistry and Laboratory Haematology, Department of Medical Laboratory Diagnostics, Faculty of Pharmacy, Wroclaw Medical University, 50‑556 Wroclaw, Poland
| | - Kornela Hałucha
- Division of Clinical Chemistry and Laboratory Haematology, Department of Medical Laboratory Diagnostics, Faculty of Pharmacy, Wroclaw Medical University, 50‑556 Wroclaw, Poland
| | - Iwona Bil-Lula
- Division of Clinical Chemistry and Laboratory Haematology, Department of Medical Laboratory Diagnostics, Faculty of Pharmacy, Wroclaw Medical University, 50‑556 Wroclaw, Poland
| |
Collapse
|
28
|
Mass Spectrometric Profiling of Extraocular Muscle and Proteomic Adaptations in the mdx-4cv Model of Duchenne Muscular Dystrophy. Life (Basel) 2021; 11:life11070595. [PMID: 34206383 PMCID: PMC8304255 DOI: 10.3390/life11070595] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 12/16/2022] Open
Abstract
Extraocular muscles (EOMs) represent a specialized type of contractile tissue with unique cellular, physiological, and biochemical properties. In Duchenne muscular dystrophy, EOMs stay functionally unaffected in the course of disease progression. Therefore, it was of interest to determine their proteomic profile in dystrophinopathy. The proteomic survey of wild type mice and the dystrophic mdx-4cv model revealed a broad spectrum of sarcomere-associated proteoforms, including components of the thick filament, thin filament, M-band and Z-disk, as well as a variety of muscle-specific markers. Interestingly, the mass spectrometric analysis revealed unusual expression levels of contractile proteins, especially isoforms of myosin heavy chain. As compared to diaphragm muscle, both proteomics and immunoblotting established isoform MyHC14 as a new potential marker in wild type EOMs, in addition to the previously identified isoforms MyHC13 and MyHC15. Comparative proteomics was employed to establish alterations in the protein expression profile between normal EOMs and dystrophin-lacking EOMs. The analysis of mdx-4cv EOMs identified elevated levels of glycolytic enzymes and molecular chaperones, as well as decreases in mitochondrial enzymes. These findings suggest a process of adaptation in dystrophin-deficient EOMs via a bioenergetic shift to more glycolytic metabolism, as well as an efficient cellular stress response in EOMs in dystrophinopathy.
Collapse
|
29
|
Rasicci DV, Kirkland O, Moonschi FH, Wood NB, Szczesna-Cordary D, Previs MJ, Wenk JF, Campbell KS, Yengo CM. Impact of regulatory light chain mutation K104E on the ATPase and motor properties of cardiac myosin. J Gen Physiol 2021; 153:212025. [PMID: 33891674 PMCID: PMC8077168 DOI: 10.1085/jgp.202012811] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/19/2021] [Indexed: 12/11/2022] Open
Abstract
Mutations in the cardiac myosin regulatory light chain (RLC, MYL2 gene) are known to cause inherited cardiomyopathies with variable phenotypes. In this study, we investigated the impact of a mutation in the RLC (K104E) that is associated with hypertrophic cardiomyopathy (HCM). Previously in a mouse model of K104E, older animals were found to develop cardiac hypertrophy, fibrosis, and diastolic dysfunction, suggesting a slow development of HCM. However, variable penetrance of the mutation in human populations suggests that the impact of K104E may be subtle. Therefore, we generated human cardiac myosin subfragment-1 (M2β-S1) and exchanged on either the wild type (WT) or K104E human ventricular RLC in order to assess the impact of the mutation on the mechanochemical properties of cardiac myosin. The maximum actin-activated ATPase activity and actin sliding velocities in the in vitro motility assay were similar in M2β-S1 WT and K104E, as were the detachment kinetic parameters, including the rate of ATP-induced dissociation and the ADP release rate constant. We also examined the mechanical performance of α-cardiac myosin extracted from transgenic (Tg) mice expressing human wild type RLC (Tg WT) or mutant RLC (Tg K104E). We found that α-cardiac myosin from Tg K104E animals demonstrated enhanced actin sliding velocities in the motility assay compared with its Tg WT counterpart. Furthermore, the degree of incorporation of the mutant RLC into α-cardiac myosin in the transgenic animals was significantly reduced compared with wild type. Therefore, we conclude that the impact of the K104E mutation depends on either the length or the isoform of the myosin heavy chain backbone and that the mutation may disrupt RLC interactions with the myosin lever arm domain.
Collapse
Affiliation(s)
- David V Rasicci
- Pennsylvania State University College of Medicine, Hershey, PA
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Jiang H, Bao J, Xing Y, Feng C, Li X, Chen Q. Proteomic Analysis of the Hemolymph After Metschnikowia bicuspidata Infection in the Chinese Mitten Crab Eriocheir sinensis. Front Immunol 2021; 12:659723. [PMID: 33868309 PMCID: PMC8047416 DOI: 10.3389/fimmu.2021.659723] [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: 01/28/2021] [Accepted: 03/16/2021] [Indexed: 12/18/2022] Open
Abstract
The “milky disease” of the Chinese mitten crab, Eriocheir sinensis, is a highly lethal fungal disease caused by Metschnikowia bicuspidata infection. To elucidate the immune responses of the hemolymph of E. sinensis to M. bicuspidata infection, a comparative analysis of the hemolymph of E. sinensis infected with M. bicuspidata and that treated with phosphate buffered saline was performed using label-free quantitative proteomics. A total of 429 proteins were identified. Using a 1.5-fold change in expression as a physiologically significant benchmark, 62 differentially expressed proteins were identified, of which 38 were significantly upregulated and 24 were significantly downregulated. The upregulated proteins mainly included cytoskeleton-related proteins (myosin regulatory light chain 2, myosin light chain alkali, tubulin α-2 chain, and tubulin β-1 chain), serine protease and serine protease inhibitor (clip domain-containing serine protease, leukocyte elastase inhibitor, serine protein inhibitor 42Dd), catalase, transferrin, and heat shock protein 70. Upregulation of these proteins indicated that phenoloxidase system, phagocytosis and the ROS systems were induced by M. bicuspidata. The downregulated proteins were mainly organ and tissue regeneration proteins (PDGF/VEGF-related factor protein, integrin-linked protein kinase homing pat-4 gene) and hemagglutination-associated proteins (hemolymph clottable protein, hemocyte protein-glutamine gamma-glutamyltransferase). Downregulation of these proteins indicated that M. bicuspidata inhibited hemocyte regeneration and hemolymph agglutination. Fifteen differentially expressed proteins related to immunity were verified using a parallel reaction monitoring method. The expression trend of these proteins was similar to that of the proteome. To the best of our knowledge, this is the first report on the proteome of E. sinensis in response to M. bicuspidata infection. These results not only provide new and important information on the immune response of crustaceans to yeast infection but also provide a basis for further understanding the molecular mechanism of complex host pathogen interactions between crustaceans and fungi.
Collapse
Affiliation(s)
- Hongbo Jiang
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| | - Jie Bao
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| | - Yuenan Xing
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| | - Chengcheng Feng
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| | - Xiaodong Li
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| | - Qijun Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, Key Laboratory of Zoonosis, Shenyang Agricultural University, Shenyang, China
| |
Collapse
|
31
|
Solís C, Solaro RJ. Novel insights into sarcomere regulatory systems control of cardiac thin filament activation. J Gen Physiol 2021; 153:211903. [PMID: 33740037 PMCID: PMC7988513 DOI: 10.1085/jgp.202012777] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 02/23/2021] [Indexed: 12/11/2022] Open
Abstract
Our review focuses on sarcomere regulatory mechanisms with a discussion of cardiac-specific modifications to the three-state model of thin filament activation from a blocked to closed to open state. We discuss modulation of these thin filament transitions by Ca2+, by crossbridge interactions, and by thick filament–associated proteins, cardiac myosin–binding protein C (cMyBP-C), cardiac regulatory light chain (cRLC), and titin. Emerging evidence supports the idea that the cooperative activation of the thin filaments despite a single Ca2+ triggering regulatory site on troponin C (cTnC) cannot be considered in isolation of other functional domains of the sarcomere. We discuss long- and short-range interactions among these domains with the regulatory units of thin filaments, including proteins at the barbed end at the Z-disc and the pointed end near the M-band. Important to these discussions is the ever-increasing understanding of the role of cMyBP-C, cRLC, and titin filaments. Detailed knowledge of these control processes is critical to the understanding of mechanisms sustaining physiological cardiac state with varying hemodynamic load, to better defining genetic and acquired cardiac disorders, and to developing targets for therapies at the level of the sarcomeres.
Collapse
Affiliation(s)
- Christopher Solís
- University of Illinois at Chicago, College of Medicine, Department of Physiology and Biophysics and Center for Cardiovascular Research, Chicago, IL
| | - R John Solaro
- University of Illinois at Chicago, College of Medicine, Department of Physiology and Biophysics and Center for Cardiovascular Research, Chicago, IL
| |
Collapse
|
32
|
Chong JX, Talbot JC, Teets EM, Previs S, Martin BL, Shively KM, Marvin CT, Aylsworth AS, Saadeh-Haddad R, Schatz UA, Inzana F, Ben-Omran T, Almusafri F, Al-Mulla M, Buckingham KJ, Harel T, Mor-Shaked H, Radhakrishnan P, Girisha KM, Nayak SS, Shukla A, Dieterich K, Faure J, Rendu J, Capri Y, Latypova X, Nickerson DA, Warshaw DM, Janssen PM, Amacher SL, Bamshad MJ, Bamshad MJ. Mutations in MYLPF Cause a Novel Segmental Amyoplasia that Manifests as Distal Arthrogryposis. Am J Hum Genet 2020; 107:293-310. [PMID: 32707087 DOI: 10.1016/j.ajhg.2020.06.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 06/18/2020] [Indexed: 02/06/2023] Open
Abstract
We identified ten persons in six consanguineous families with distal arthrogryposis (DA) who had congenital contractures, scoliosis, and short stature. Exome sequencing revealed that each affected person was homozygous for one of two different rare variants (c.470G>T [p.Cys157Phe] or c.469T>C [p.Cys157Arg]) affecting the same residue of myosin light chain, phosphorylatable, fast skeletal muscle (MYLPF). In a seventh family, a c.487G>A (p.Gly163Ser) variant in MYLPF arose de novo in a father, who transmitted it to his son. In an eighth family comprised of seven individuals with dominantly inherited DA, a c.98C>T (p.Ala33Val) variant segregated in all four persons tested. Variants in MYLPF underlie both dominant and recessively inherited DA. Mylpf protein models suggest that the residues associated with dominant DA interact with myosin whereas the residues altered in families with recessive DA only indirectly impair this interaction. Pathological and histological exam of a foot amputated from an affected child revealed complete absence of skeletal muscle (i.e., segmental amyoplasia). To investigate the mechanism for this finding, we generated an animal model for partial MYLPF impairment by knocking out zebrafish mylpfa. The mylpfa mutant had reduced trunk contractile force and complete pectoral fin paralysis, demonstrating that mylpf impairment most severely affects limb movement. mylpfa mutant muscle weakness was most pronounced in an appendicular muscle and was explained by reduced myosin activity and fiber degeneration. Collectively, our findings demonstrate that partial loss of MYLPF function can lead to congenital contractures, likely as a result of degeneration of skeletal muscle in the distal limb.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Michael J Bamshad
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Brotman-Baty Institute, Seattle, WA 98195, USA; Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA; Seattle Children's Hospital, Seattle, WA 98105, USA.
| |
Collapse
|
33
|
Manivannan SN, Darouich S, Masmoudi A, Gordon D, Zender G, Han Z, Fitzgerald-Butt S, White P, McBride KL, Kharrat M, Garg V. Novel frameshift variant in MYL2 reveals molecular differences between dominant and recessive forms of hypertrophic cardiomyopathy. PLoS Genet 2020; 16:e1008639. [PMID: 32453731 PMCID: PMC7274480 DOI: 10.1371/journal.pgen.1008639] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 06/05/2020] [Accepted: 01/29/2020] [Indexed: 12/18/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is characterized by thickening of the ventricular muscle without dilation and is often associated with dominant pathogenic variants in cardiac sarcomeric protein genes. Here, we report a family with two infants diagnosed with infantile-onset HCM and mitral valve dysplasia that led to death before one year of age. Using exome sequencing, we discovered that one of the affected children had a homozygous frameshift variant in Myosin light chain 2 (MYL2:NM_000432.3:c.431_432delCT: p.Pro144Argfs*57;MYL2-fs), which alters the last 20 amino acids of the protein and is predicted to impact the most C-terminal of the three EF-hand domains in MYL2. The parents are unaffected heterozygous carriers of the variant and the variant is absent in control cohorts from gnomAD. The absence of the phenotype in carriers and the infantile presentation of severe HCM is in contrast to HCM associated with dominant MYL2 variants. Immunohistochemical analysis of the ventricular muscle of the deceased patient with the MYL2-fs variant showed a marked reduction of MYL2 expression compared to an unaffected control. In vitro overexpression studies further indicate that the MYL2-fs variant is actively degraded. In contrast, an HCM-associated missense variant (MYL2:p.Gly162Arg) and three other MYL2 stop-gain variants (p.E22*, p.K62*, p.E97*) that result in loss of the EF domains are stably expressed but show impaired localization. The degradation of the MYL2-fs can be rescued by inhibiting the cell’s proteasome function supporting a post-translational effect of the variant. In vivo rescue experiments with a Drosophila MYL2-homolog (Mlc2) knockdown model indicate that neither the MYL2-fs nor the MYL2:p.Gly162Arg variant supports normal cardiac function. The tools that we have generated provide a rapid screening platform for functional assessment of variants of unknown significance in MYL2. Our study supports an autosomal recessive model of inheritance for MYL2 loss-of-function variants in infantile HCM and highlights the variant-specific molecular differences found in MYL2-associated cardiomyopathy. We report a novel frameshift variant in MYL2 that is associated with a severe form of infantile-onset hypertrophic cardiomyopathy. The impact of the variant is only observed in the recessive form of the disease found in the proband and not in the parents who are carriers of the variant. This contrasts with other dominant variants in MYL2 that are associated with cardiomyopathies. We compared the stability of this variant to that of other cardiomyopathy associated MYL2 variants and found molecular differences that correlated with disease pathology. We also show different protein domain requirements for stability and localization of MYL2 in cardiomyocytes. Furthermore, we used a fly model to demonstrate functional deficits due to the variant in the developing heart. Overall, our study shows a molecular mechanism by which loss-of-function variants in MYL2 are recessive while missense variants are dominant. We highlight the use of exome sequencing and functional testing to assist in the diagnosis of rare forms of disease where pathogenicity of the variant is not obvious. The new tools we developed for in vitro functional study and the fly fluorescent reporter analysis will permit rapid analysis of MYL2 variants of unknown significance.
Collapse
Affiliation(s)
- Sathiya N. Manivannan
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Heart Center, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Sihem Darouich
- University of Tunis El Manar, Faculty of Medicine of Tunis, LR99ES10 Laboratory of Human Genetics, Tunis, Tunisia
- * E-mail: (SD); (VG)
| | - Aida Masmoudi
- University of Tunis El Manar, Faculty of Medicine of Tunis, Department of Embryo-Fetopathology, Maternity and Neonatology Center, Tunis, Tunisia
| | - David Gordon
- Institute for Genomic Medicine at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Gloria Zender
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Zhe Han
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Sara Fitzgerald-Butt
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Heart Center, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, United States of America
| | - Peter White
- Institute for Genomic Medicine at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, United States of America
| | - Kim L. McBride
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Heart Center, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, United States of America
| | - Maher Kharrat
- University of Tunis El Manar, Faculty of Medicine of Tunis, LR99ES10 Laboratory of Human Genetics, Tunis, Tunisia
| | - Vidu Garg
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Heart Center, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, United States of America
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (SD); (VG)
| |
Collapse
|