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Ridha F, Gromiha MM. MPA-Pred: A machine learning approach for predicting the binding affinity of membrane protein-protein complexes. Proteins 2024; 92:499-508. [PMID: 37949651 DOI: 10.1002/prot.26633] [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: 05/05/2023] [Revised: 10/05/2023] [Accepted: 10/25/2023] [Indexed: 11/12/2023]
Abstract
Membrane protein-protein interactions are essential for several functions including cell signaling, ion transport, and enzymatic activity. These interactions are mainly dictated by their binding affinities. Although several methods are available for predicting the binding affinity of protein-protein complexes, there exists no specific method for membrane protein-protein complexes. In this work, we collected the experimental binding affinity data for a set of 114 membrane protein-protein complexes and derived several structure and sequence-based features. Our analysis on the relationship between binding affinity and the features revealed that the important factors mainly depend on the type of membrane protein and the functional class of the protein. Specifically, aromatic and charged residues at the interface, and aromatic-aromatic and electrostatic interactions are found to be important to understand the binding affinity. Further, we developed a method, MPA-Pred, for predicting the binding affinity of membrane protein-protein complexes using a machine learning approach. It showed an average correlation and mean absolute error of 0.83 and 0.91 kcal/mol, respectively, using the jack-knife test on a set of 114 complexes. We have also developed a web server and it is available at https://web.iitm.ac.in/bioinfo2/MPA-Pred/. This method can be used for predicting the affinity of membrane protein-protein complexes at a large scale and aid to improve drug design strategies.
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Affiliation(s)
- Fathima Ridha
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
| | - M Michael Gromiha
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
- Department of Computer Science, National University of Singapore, Singapore, Singapore
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2
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Halder R, Warshel A. Energetic and structural insights behind calcium induced conformational transition in calmodulin. Proteins 2024; 92:384-394. [PMID: 37915244 PMCID: PMC10872638 DOI: 10.1002/prot.26620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 10/01/2023] [Accepted: 10/10/2023] [Indexed: 11/03/2023]
Abstract
Calmodulin (CaM) is a key signaling protein that triggers several cellular and physiological processes inside the cell. Upon binding with calcium ion, CaM undergoes large scale conformational transition from a closed state to an open state that facilitates its interaction with various target protein and regulates their activity. This work explores the origin of the energetic and structural variation of the wild type and mutated CaM and explores the molecular origin for the structural differences between them. We first calculated the sequential calcium binding energy to CaM using the PDLD/S-LRA/β approach. This study shows a very good correlation with experimental calcium binding energies. Next we calculated the calcium binding energies to the wild type CaM and several mutated CaM systems which were reported experimentally. On the structural aspect, it has been reported experimentally that certain mutation (Q41L-K75I) in calcium bound CaM leads to complete conformational transition from an open to a closed state. By using equilibrium molecular dynamics simulation, free energy calculation and contact frequency map analysis, we have shown that the formation of a cluster of long-range hydrophobic contacts, initiated by the Q41L-K75I CaM variant is the driving force behind its closing motion. This study unravels the energetics and structural aspects behind calcium ion induced conformational changes in wild type CaM and its variant.
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Affiliation(s)
- Ritaban Halder
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
| | - Arieh Warshel
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
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3
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Rodnyy AY, Kondaurova EM, Tsybko AS, Popova NK, Kudlay DA, Naumenko VS. The brain serotonin system in autism. Rev Neurosci 2024; 35:1-20. [PMID: 37415576 DOI: 10.1515/revneuro-2023-0055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 06/10/2023] [Indexed: 07/08/2023]
Abstract
Autism spectrum disorders (ASDs) are among the most common neurodevelopmental diseases. These disorders are characterized by lack of social interaction, by repetitive behavior, and often anxiety and learning disabilities. The brain serotonin (5-HT) system is known to be crucially implicated in a wide range of physiological functions and in the control of different kinds of normal and pathological behavior. A growing number of studies indicate the involvement of the brain 5-HT system in the mechanisms underlying both ASD development and ASD-related behavioral disorders. There are some review papers describing the role of separate key players of the 5-HT system in an ASD and/or autistic-like behavior. In this review, we summarize existing data on the participation of all members of the brain 5-HT system, namely, 5-HT transporter, tryptophan hydroxylase 2, MAOA, and 5-HT receptors, in autism in human and various animal models. Additionally, we describe the most recent studies involving modern techniques for in vivo regulation of gene expression that are aimed at identifying exact roles of 5-HT receptors, MAOA, and 5-HT transporter in the mechanisms underlying autistic-like behavior. Altogether, results of multiple research articles show that the brain 5-HT system intimately partakes in the control of some types of ASD-related behavior, and that specific changes in a function of a certain 5-HT receptor, transporter, and/or enzyme may normalize this aberrant behavior. These data give hope that some of clinically used 5-HT-related drugs have potential for ASD treatment.
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Affiliation(s)
- Alexander Ya Rodnyy
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Akad. Lavrentyeva Ave. 10, Novosibirsk 630090, Russia
| | - Elena M Kondaurova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Akad. Lavrentyeva Ave. 10, Novosibirsk 630090, Russia
| | - Anton S Tsybko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Akad. Lavrentyeva Ave. 10, Novosibirsk 630090, Russia
| | - Nina K Popova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Akad. Lavrentyeva Ave. 10, Novosibirsk 630090, Russia
| | - Dmitry A Kudlay
- NRC Institute of Immunology FMBA of Russia, Kashirskoe Highway 24, Moscow 115522, Russia
- Sechenov's University, 8-2 Trubetskaya Str., Moscow 119991, Russia
| | - Vladimir S Naumenko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Akad. Lavrentyeva Ave. 10, Novosibirsk 630090, Russia
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Teralı K, Türkyılmaz A, Sağer SG, Çebi AH. Prediction of molecular phenotypes for novel SCN1A variants from a Turkish genetic epilepsy syndromes cohort and report of two new patients with recessive Dravet syndrome. Clin Transl Sci 2024; 17:e13679. [PMID: 37955180 PMCID: PMC10772300 DOI: 10.1111/cts.13679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 09/23/2023] [Accepted: 09/29/2023] [Indexed: 11/14/2023] Open
Abstract
Dravet syndrome and genetic epilepsy with febrile seizures plus (GEFS+) are both epilepsy syndromes that can be attributed to deleterious mutations occurring in SCN1A, the gene encoding the pore-forming α-subunit of the NaV 1.1 voltage-gated sodium channel predominantly expressed in the central nervous system. In this research endeavor, our goal is to expand our prior cohort of Turkish patients affected by SCN1A-positive genetic epilepsy disorders. This will be accomplished by incorporating two recently discovered and infrequent index cases who possess a novel biallelic (homozygous) SCN1A missense variant, namely E158G, associated with Dravet syndrome. Furthermore, our intention is to use computational techniques to predict the molecular phenotypes of each distinct SCN1A variant that has been detected to date within our center. The correlation between genotype and phenotype in Dravet syndrome/GEFS+ is intricate and necessitates meticulous clinical investigation as well as advanced scientific exploration. Broadened mechanistic and structural insights into NaV 1.1 dysfunction offer significant promise in facilitating the development of targeted and effective therapies, which will ultimately enhance clinical outcomes in the treatment of epilepsy.
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Affiliation(s)
- Kerem Teralı
- Department of Medical Biochemistry, Faculty of MedicineCyprus International UniversityNicosiaCyprus
| | - Ayberk Türkyılmaz
- Department of Medical Genetics, Faculty of MedicineKaradeniz Technical UniversityTrabzonTurkey
| | - Safiye Güneş Sağer
- Department of Pediatric NeurologyKartal Dr. Lütfi Kırdar City HospitalİstanbulTurkey
| | - Alper Han Çebi
- Department of Medical Genetics, Faculty of MedicineKaradeniz Technical UniversityTrabzonTurkey
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Brohus M, Busuioc AO, Wimmer R, Nyegaard M, Overgaard MT. Calmodulin mutations affecting Gly114 impair binding to the Na V1.5 IQ-domain. Front Pharmacol 2023; 14:1210140. [PMID: 37663247 PMCID: PMC10469309 DOI: 10.3389/fphar.2023.1210140] [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: 04/24/2023] [Accepted: 07/25/2023] [Indexed: 09/05/2023] Open
Abstract
Missense variants in CALM genes encoding the Ca2+-binding protein calmodulin (CaM) cause severe cardiac arrhythmias. The disease mechanisms have been attributed to dysregulation of RyR2, for Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) and/or CaV1.2, for Long-QT Syndrome (LQTS). Recently, a novel CALM2 variant, G114R, was identified in a mother and two of her four children, all of whom died suddenly while asleep at a young age. The G114R variant impairs closure of CaV1.2 and RyR2, consistent with a CPVT and/or mild LQTS phenotype. However, the children carrying the CALM2 G114R variant displayed a phenotype commonly observed with variants in NaV1.5, i.e., Brugada Syndrome (BrS) or LQT3, where death while asleep is a common feature. We therefore hypothesized that the G114R variant specifically would interfere with NaV1.5 binding. Here, we demonstrate that CaM binding to the NaV1.5 IQ-domain is severely impaired for two CaM variants G114R and G114W. The impact was most severe at low and intermediate Ca2+ concentrations (up to 4 µM) resulting in more than a 50-fold reduction in NaV1.5 binding affinity, and a smaller 1.5 to 11-fold reduction at high Ca2+ concentrations (25-400 µM). In contrast, the arrhythmogenic CaM-N98S variant only induced a 1.5-fold reduction in NaV1.5 binding and only at 4 µM Ca2+. A non-arrhythmogenic I10T variant in CaM did not impair NaV1.5 IQ binding. These data suggest that the interaction between NaV1.5 and CaM is decreased with certain CaM variants, which may alter the cardiac sodium current, INa. Overall, these results suggest that the phenotypic spectrum of calmodulinopathies may likely expand to include BrS- and/or LQT3-like traits.
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Affiliation(s)
- Malene Brohus
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Ana-Octavia Busuioc
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Reinhard Wimmer
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Mette Nyegaard
- Department of Health Science and Technology, Aalborg University, Gistrup, Denmark
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Wu X, Singla S, Liu JJ, Hong L. The role of macrophage ion channels in the progression of atherosclerosis. Front Immunol 2023; 14:1225178. [PMID: 37588590 PMCID: PMC10425548 DOI: 10.3389/fimmu.2023.1225178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/10/2023] [Indexed: 08/18/2023] Open
Abstract
Atherosclerosis is a complex inflammatory disease that affects the arteries and can lead to severe complications such as heart attack and stroke. Macrophages, a type of immune cell, play a crucial role in atherosclerosis initiation and progression. Emerging studies revealed that ion channels regulate macrophage activation, polarization, phagocytosis, and cytokine secretion. Moreover, macrophage ion channel dysfunction is implicated in macrophage-derived foam cell formation and atherogenesis. In this context, exploring the regulatory role of ion channels in macrophage function and their impacts on the progression of atherosclerosis emerges as a promising avenue for research. Studies in the field will provide insights into novel therapeutic targets for the treatment of atherosclerosis.
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Affiliation(s)
- Xin Wu
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Sidhant Singla
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Jianhua J. Liu
- Department of Pathology, University of Illinois at Chicago, Chicago, IL, United States
| | - Liang Hong
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, United States
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Wang M, Zhao M, Xu S, Zheng Z, Zhang J, Pan W, Yin Z, Liu J, Wei C, Wan J, Xu Y. TRPA1 deficiency attenuates cardiac fibrosis via regulating GRK5/NFAT signaling in diabetic rats. Biochem Pharmacol 2023:115671. [PMID: 37380112 DOI: 10.1016/j.bcp.2023.115671] [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: 05/17/2023] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 06/30/2023]
Abstract
BACKGROUND Transient receptor potential ankyrin 1 (TRPA1) has been linked to the development of various cardiovascular diseases, but its role in diabetic cardiomyopathy is not well understood. This study aimed to investigate the protective effects of TRPA1 deficiency on diabetic cardiomyopathy in rats with streptozotocin-induced diabetes and in neonatal rat cardiac fibroblasts (CFs) exposed to high glucose (HG). METHODS Cardiac TRPA1 expression levels were measured in diabetic rats. Cardiac function, remodeling, and fibrosis were analyzed in Sprague-Dawley (SD) rats and TRPA1-deficient rats with diabetic cardiomyopathy. In vitro, fibrosis was measured in CFs exposed to HG. Additionally, 1,8-cineole, a natural inhibitor of TRPA1, was used to treat SD rats with diabetic cardiomyopathy. RESULTS TRPA1 expression was increased in the heart tissue of diabetic rats and in CFs treated with HG. TRPA1 deficiency significantly improved cardiac function in diabetic rats, as evidenced by improved echocardiography and reduced cardiac hypertrophy and fibrosis. In vitro, TRPA1 deficiency suppressed the transformation of HG-induced CFs into myofibroblasts. The cardioprotective effect of TRPA1 deficiency was found to inhibit cardiac fibrosis by regulating GRK5/NFAT signaling. Furthermore, inhibition of GRK5/NFAT signaling abolished the promotion of CF transformation into myofibroblasts by TRPA1 activation. Inhibition of TRPA1 activation by 1,8-cineole reduced cardiac dysfunction and remodeling in diabetic rats by regulating GRK5/NFAT signaling. CONCLUSIONS TRPA1 deficiency reduced cardiac fibrosis in diabetic rats and inhibited HG-induced CF activation in vitro by regulating GRK5/NFAT signaling. The TRPA1 inhibitor 1,8-cineole may serve as a novel therapeutic agent for the treatment of diabetic cardiomyopathy.
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Affiliation(s)
- Menglong Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Mengmeng Zhao
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Shuwan Xu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Zihui Zheng
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Jishou Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Wei Pan
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Zheng Yin
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Jianfang Liu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Cheng Wei
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China
| | - Jun Wan
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China.
| | - Yao Xu
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China; Cardiovascular Research Institute, Wuhan University, Wuhan 430060, PR China; Hubei Key Laboratory of Cardiology, Wuhan 430060, PR China.
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Ohla J, Wiciński M, Słupski M, Zabrzyński J, Malinowski B. Cyclic AMP but Not Calmodulin as a Potential Wasoconstrictor in Simulated Reperfusion. Int J Mol Sci 2023; 24:10355. [PMID: 37373502 DOI: 10.3390/ijms241210355] [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: 04/06/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
The phenomena of ischemia and reperfusion are associated with the pathological background of cardiovascular diseases. Ischemia is initiated by ischemia reperfusion injury (IRI), which involves disruption of intracellular signaling pathways and causes cell death. The aim of this study was to assess the reactivity of vascular smooth muscle cells in the conditions of induced ischemia and reperfusion, and to determine the mechanisms leading to contractility disorders. This study was conducted using classical pharmacometric methods on an isolated model of the rat caudal artery. The experiment consisted of the analysis of the final and initial perfusate pressure measurements after induction of arterial contraction with phenylephrine in the presence of forskolin and A7 hydrochloride, two ligands modifying the contractility of vascular smooth muscle cells (VSMC). The pharmacometric analysis showed that in simulated reperfusion, cyclic nucleotides have a vasoconstrictive effect, and calmodulin has a vasodilating effect. The responsiveness of vascular smooth muscle cells to the vasopressor effects of α1-adrenomimetics during reperfusion may change uncontrollably, and the effects of secondary messengers may be counter physiological. Further studies are needed to evaluate the function of other second messengers on VSMCs in the process of ischemia and reperfusion.
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Affiliation(s)
- Jakub Ohla
- Department of Orthopaedics and Traumatology, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-090 Bydgoszcz, Poland
| | - Michał Wiciński
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-090 Bydgoszcz, Poland
| | - Maciej Słupski
- Department of Hepatobiliary and General Surgery, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-090 Bydgoszcz, Poland
| | - Jan Zabrzyński
- Department of Orthopaedics and Traumatology, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-090 Bydgoszcz, Poland
| | - Bartosz Malinowski
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-090 Bydgoszcz, Poland
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Calmodulin variant E140G associated with long QT syndrome impairs CaMKIIδ autophosphorylation and L-type calcium channel inactivation. J Biol Chem 2023; 299:102777. [PMID: 36496072 PMCID: PMC9830374 DOI: 10.1016/j.jbc.2022.102777] [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: 07/28/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/13/2022] Open
Abstract
Long QT syndrome (LQTS) is a human inherited heart condition that can cause life-threatening arrhythmia including sudden cardiac death. Mutations in the ubiquitous Ca2+-sensing protein calmodulin (CaM) are associated with LQTS, but the molecular mechanism by which these mutations lead to irregular heartbeats is not fully understood. Here, we use a multidisciplinary approach including protein biophysics, structural biology, confocal imaging, and patch-clamp electrophysiology to determine the effect of the disease-associated CaM mutation E140G on CaM structure and function. We present novel data showing that mutant-regulated CaMKIIδ kinase activity is impaired with a significant reduction in enzyme autophosphorylation rate. We report the first high-resolution crystal structure of a LQTS-associated CaM variant in complex with the CaMKIIδ peptide, which shows significant structural differences, compared to the WT complex. Furthermore, we demonstrate that the E140G mutation significantly disrupted Cav1.2 Ca2+/CaM-dependent inactivation, while cardiac ryanodine receptor (RyR2) activity remained unaffected. In addition, we show that the LQTS-associated mutation alters CaM's Ca2+-binding characteristics, secondary structure content, and interaction with key partners involved in excitation-contraction coupling (CaMKIIδ, Cav1.2, RyR2). In conclusion, LQTS-associated CaM mutation E140G severely impacts the structure-function relationship of CaM and its regulation of CaMKIIδ and Cav1.2. This provides a crucial insight into the molecular factors contributing to CaM-mediated arrhythmias with a central role for CaMKIIδ.
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Wu X, Li Y, Hong L. Effects of Mexiletine on a Race-specific Mutation in Nav1.5 Associated With Long QT Syndrome. Front Physiol 2022; 13:904664. [PMID: 35864896 PMCID: PMC9294368 DOI: 10.3389/fphys.2022.904664] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/14/2022] [Indexed: 11/13/2022] Open
Abstract
The voltage-gated sodium channel Nav1.5 plays an essential role in the generation and propagation of action potential in cardiomyocytes. Mutations in Nav1.5 have been associated with LQT syndrome, Brugada syndrome, and sudden arrhythmia death syndrome. Genetic studies showed that Nav1.5 mutations vary across race-ethnic groups. Here we investigated an Asian-specific mutation Nav1.5-P1090L associated with LQT syndrome. We found that Nav1.5-P1090L mutation perturbed the sodium channel function. It altered the gating process of the channel and exhibited an enhanced window current. Treatment with mexiletine reversed the depolarization shift of the steady-state inactivation produced by P1090L. Mexiletine also modified the recovery from steady-state inactivation and the development of inactivation of P1090L. It rescued the dysfunctional inactivation of P1090L and reduced the P1090L channel’s availability.
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Affiliation(s)
- Xin Wu
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Yawei Li
- Department of Preventive Medicine, Northwestern University, Chicago, IL, United States
| | - Liang Hong
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- *Correspondence: Liang Hong,
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11
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Chen TS, Lai MC, Huang HYI, Wu SN, Huang CW. Immunity, Ion Channels and Epilepsy. Int J Mol Sci 2022; 23:ijms23126446. [PMID: 35742889 PMCID: PMC9224225 DOI: 10.3390/ijms23126446] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/03/2022] [Accepted: 06/07/2022] [Indexed: 12/10/2022] Open
Abstract
Epilepsy is a common chronic neurological disorder in modern society. One of the major unmet challenges is that current antiseizure medications are basically not disease-modifying. Among the multifaceted etiologies of epilepsy, the role of the immune system has attracted considerable attention in recent years. It is known that both innate and adaptive immunity can be activated in response to insults to the central nervous system, leading to seizures. Moreover, the interaction between ion channels, which have a well-established role in epileptogenesis and epilepsy, and the immune system is complex and is being actively investigated. Some examples, including the interaction between ion channels and mTOR pathways, will be discussed in this paper. Furthermore, there has been substantial progress in our understanding of the pathophysiology of epilepsy associated with autoimmune encephalitis, and numerous neural-specific autoantibodies have been found and documented. Early recognition of immune-mediated epilepsy is important, especially in cases of pharmacoresistant epilepsy and in the presence of signs of autoimmune encephalitis, as early intervention with immunotherapy shows promise.
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Affiliation(s)
- Tsang-Shan Chen
- Department of Neurology, Tainan Sin-Lau Hospital, Tainan 701002, Taiwan;
| | - Ming-Chi Lai
- Department of Pediatrics, Chi-Mei Medical Center, Tainan 71004, Taiwan;
| | | | - Sheng-Nan Wu
- Department of Physiology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan;
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan 70101, Taiwan
| | - Chin-Wei Huang
- Department of Neurology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan
- Correspondence: ; Tel.: +886-6-2353535 (ext. 5485)
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12
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Wu X, Li Y, Maienschein-Cline M, Feferman L, Wu L, Hong L. RNA-Seq Analyses Reveal Roles of the HVCN1 Proton Channel in Cardiac pH Homeostasis. Front Cell Dev Biol 2022; 10:860502. [PMID: 35372367 PMCID: PMC8967321 DOI: 10.3389/fcell.2022.860502] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 02/16/2022] [Indexed: 12/13/2022] Open
Abstract
The voltage-gated proton channel HVCN1 is a member of the voltage-gated ion channel family. HVCN1 channel controls acid extrusion and regulates pH homeostasis in various cell types. Recent evidence indicated that the HVCN1 channel was associated with cardiac function. To investigate the role of HVCN1 in cardiac myocytes, we performed an RNA sequencing analysis of murine hearts and showed that HVCN1 null hearts exhibited a differential transcriptome profile compared with wild-type hearts. The RNA-seq data indicating impaired pH homeostasis in HVCN1 null hearts were the downregulated NADPH oxidoreductases (NOXs) and decreased expression of Cl−/HCO3− exchanger, indicating HVCN1 is a regulator of gene transcriptional networks controlling NOX signaling and CO2 homeostasis in the heart. Additionally, HVCN1 null hearts exhibited differential expression of cardiac ion channels, suggesting a potential role of HVCN1 in cardiac electrophysiological remodeling. The study highlights the importance of HVCN1 in cardiac function and may present a novel target associated with heart diseases.
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Affiliation(s)
- Xin Wu
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Yawei Li
- Department of Preventive Medicine, Northwestern University, Chicago, IL, United States
| | - Mark Maienschein-Cline
- Research Informatics Core, Research Resources Center, University of Illinois at Chicago, Chicago, IL, United States
| | - Leonid Feferman
- Research Informatics Core, Research Resources Center, University of Illinois at Chicago, Chicago, IL, United States
| | - Longjun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | - Liang Hong
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- *Correspondence: Liang Hong,
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