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Nesterov SV, Ilyinsky NS, Plokhikh KS, Manuylov VD, Chesnokov YM, Vasilov RG, Kuznetsova IM, Turoverov KK, Gordeliy VI, Fonin AV, Uversky VN. Order wrapped in chaos: On the roles of intrinsically disordered proteins and RNAs in the arrangement of the mitochondrial enzymatic machines. Int J Biol Macromol 2024; 267:131455. [PMID: 38588835 DOI: 10.1016/j.ijbiomac.2024.131455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 04/10/2024]
Abstract
The analysis of cryo-electron tomography images of human and rat mitochondria revealed that the mitochondrial matrix is at least as crowded as the cytosol. To mitigate the crowding effects, metabolite transport in the mitochondria primarily occurs through the intermembrane space, which is significantly less crowded. The scientific literature largely ignores how enzyme systems and metabolite transport are organized in the crowded environment of the mitochondrial matrix. Under crowded conditions, multivalent interactions carried out by disordered protein regions (IDRs), may become extremely important. We analyzed the human mitochondrial proteome to determine the presence and physiological significance of IDRs. Despite mitochondrial proteins being generally more ordered than cytosolic or overall proteome proteins, disordered regions plays a significant role in certain mitochondrial compartments and processes. Even in highly ordered enzyme systems, there are proteins with long IDRs. Some IDRs act as binding elements between highly ordered subunits, while the roles of others are not yet established. Mitochondrial systems, like their bacterial ancestors, rely less on IDRs and more on RNA for LLPS compartmentalization. More evolutionarily advanced subsystems that enable mitochondria-cell interactions contain more IDRs. The study highlights the crucial and often overlooked role played by IDRs and non-coding RNAs in mitochondrial organization.
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Affiliation(s)
- Semen V Nesterov
- National Research Center "Kurchatov Institute", Moscow 123182, Russia; Moscow Institute of Physics and Techonology, Dolgoprudny, Moscow Region 141701, Russia; Institute of Cytology, Russian Academy of Sciences, Saint Petersburg 194064, Russia.
| | - Nikolay S Ilyinsky
- Moscow Institute of Physics and Techonology, Dolgoprudny, Moscow Region 141701, Russia.
| | | | - Vladimir D Manuylov
- Moscow Institute of Physics and Techonology, Dolgoprudny, Moscow Region 141701, Russia
| | - Yuriy M Chesnokov
- National Research Center "Kurchatov Institute", Moscow 123182, Russia
| | - Raif G Vasilov
- National Research Center "Kurchatov Institute", Moscow 123182, Russia
| | - Irina M Kuznetsova
- Institute of Cytology, Russian Academy of Sciences, Saint Petersburg 194064, Russia
| | | | - Valentin I Gordeliy
- Institut de Biologie Structurale Jean-Pierre Ebel, Université Grenoble Alpes-Commissariat à l'Energie Atomique et aux Energies Alternatives-CNRS, 38027 Grenoble, France
| | - Alexander V Fonin
- Institute of Cytology, Russian Academy of Sciences, Saint Petersburg 194064, Russia
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC07, Tampa, FL 33612, USA.
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Chen KY, Liu Z, Yi J, Hui YP, Song YN, Lu JH, Chen HJ, Yang SY, Hu XY, Zhang DS, Liang GY. PDHA1 Alleviates Myocardial Ischemia-Reperfusion Injury by Improving Myocardial Insulin Resistance During Cardiopulmonary Bypass Surgery in Rats. Cardiovasc Drugs Ther 2023:10.1007/s10557-023-07501-9. [PMID: 37610688 DOI: 10.1007/s10557-023-07501-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/03/2023] [Indexed: 08/24/2023]
Abstract
OBJECTIVE Cardiopulmonary bypass (CPB) is a requisite technique for thoracotomy in advanced cardiovascular surgery. However, the consequent myocardial ischemia-reperfusion injury (MIRI) is the primary culprit behind cardiac dysfunction and fatal consequences post-operation. Prior research has posited that myocardial insulin resistance (IR) plays a vital role in exacerbating the progression of MIRI. Nonetheless, the exact mechanisms underlying this phenomenon remain obscure. METHODS We constructed pyruvate dehydrogenase E1 α subunit (PDHA1) interference and overexpression rats and used ascending aorta occlusion in an in vivo model of CPB-MIRI. We devised an in vivo model of CPB-MIRI by constructing rat models with both pyruvate dehydrogenase E1α subunit (PDHA1) interference and overexpression through ascending aorta occlusion. We analyzed myocardial glucose metabolism and the degree of myocardial injury using functional monitoring, biochemical assays, and histological analysis. RESULTS We discovered a clear downregulation of glucose transporter 4 (GLUT4) protein content expression in the CPB I/R model. In particular, cardiac-specific PDHA1 interference resulted in exacerbated cardiac dysfunction, significantly increased myocardial infarction area, more pronounced myocardial edema, and markedly increased cardiomyocyte apoptosis. Notably, the opposite effect was observed with PDHA1 overexpression, leading to a mitigated cardiac dysfunction and decreased incidence of myocardial infarction post-global ischemia. Mechanistically, PDHA1 plays a crucial role in regulating the protein content expression of GLUT4 on cardiomyocytes, thereby controlling the uptake and utilization of myocardial glucose, influencing the development of myocardial insulin resistance, and ultimately modulating MIRI. CONCLUSION Overall, our study sheds new light on the pivotal role of PDHA1 in glucose metabolism and the development of myocardial insulin resistance. Our findings hold promising therapeutic potential for addressing the deleterious effects of MIRI in patients.
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Affiliation(s)
- Kai-Yuan Chen
- Department of Cardiovascular Surgery, the Affiliated Hospital of Guizhou Medical University, Beijing Road, Yunyan District, Guiyang, 550001, Guizhou Province, China
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China
| | - Zhou Liu
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China
| | - Jing Yi
- Department of Anesthesiology, Affiliated Hospital of Guizhou Medical University, Guiyang, 550001, Guizhou Province, China
| | - Yong-Peng Hui
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China
| | - Ying-Nan Song
- Department of Cardiovascular Surgery, the Affiliated Hospital of Guizhou Medical University, Beijing Road, Yunyan District, Guiyang, 550001, Guizhou Province, China
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China
| | - Jun-Hou Lu
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China
| | - Hong-Jin Chen
- Department of Cardiovascular Surgery, the Affiliated Hospital of Guizhou Medical University, Beijing Road, Yunyan District, Guiyang, 550001, Guizhou Province, China
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China
| | - Si-Yuan Yang
- Department of Cardiovascular Surgery, the Affiliated Hospital of Guizhou Medical University, Beijing Road, Yunyan District, Guiyang, 550001, Guizhou Province, China
| | - Xuan-Yi Hu
- Department of Cardiovascular Surgery, the Affiliated Hospital of Guizhou Medical University, Beijing Road, Yunyan District, Guiyang, 550001, Guizhou Province, China
| | - Deng-Shen Zhang
- Department of Cardiovascular Surgery, the Affiliated Hospital of Zunyi Medical University, Zunyi, 563009, Guizhou Province, China
| | - Gui-You Liang
- Department of Cardiovascular Surgery, the Affiliated Hospital of Guizhou Medical University, Beijing Road, Yunyan District, Guiyang, 550001, Guizhou Province, China.
- Translational Medicine Research Center, Guizhou Medical University, Guiyang, 550025, Guizhou Province, China.
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3
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Liu S, Xia X, Zhen J, Li Z, Zhou ZH. Structures and comparison of endogenous 2-oxoglutarate and pyruvate dehydrogenase complexes from bovine kidney. Cell Discov 2022; 8:126. [PMID: 36414632 PMCID: PMC9681731 DOI: 10.1038/s41421-022-00487-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 10/20/2022] [Indexed: 11/23/2022] Open
Abstract
The α-keto acid dehydrogenase complex family catalyzes the essential oxidative decarboxylation of α-keto acids to yield acyl-CoA and NADH. Despite performing the same overarching reaction, members of the family have different component structures and structural organization between each other and across phylogenetic species. While native structures of α-keto acid dehydrogenase complexes from bacteria and fungi became available recently, the atomic structure and organization of their mammalian counterparts in native states remain unknown. Here, we report the cryo-electron microscopy structures of the endogenous cubic 2-oxoglutarate dehydrogenase complex (OGDC) and icosahedral pyruvate dehydrogenase complex (PDC) cores from bovine kidney determined at resolutions of 3.5 Å and 3.8 Å, respectively. The structures of multiple proteins were reconstructed from a single lysate sample, allowing direct structural comparison without the concerns of differences arising from sample preparation and structure determination. Although native and recombinant E2 core scaffold structures are similar, the native structures are decorated with their peripheral E1 and E3 subunits. Asymmetric sub-particle reconstructions support heterogeneity in the arrangements of these peripheral subunits. In addition, despite sharing a similar monomeric fold, OGDC and PDC E2 cores have distinct interdomain and intertrimer interactions, which suggests a means of modulating self-assembly to mitigate heterologous binding between mismatched E2 species. The lipoyl moiety lies near a mobile gatekeeper within the interdomain active site of OGDC E2 and PDC E2. Analysis of the twofold related intertrimer interface identified secondary structural differences and chemical interactions between icosahedral and cubic geometries of the core. Taken together, our study provides a direct structural comparison of OGDC and PDC from the same source and offers new insights into determinants of interdomain interactions and of architecture diversity among α-keto acid dehydrogenase complexes.
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Affiliation(s)
- Shiheng Liu
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
| | - Xian Xia
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
| | - James Zhen
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
- Molecular Biology Institute, UCLA, Los Angeles, CA, USA
| | - Zihang Li
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA
| | - Z Hong Zhou
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA, USA.
- California NanoSystems Institute, UCLA, Los Angeles, CA, USA.
- Molecular Biology Institute, UCLA, Los Angeles, CA, USA.
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Gokcan H, Bedoyan JK, Isayev O. Simulations of Pathogenic E1α Variants: Allostery and Impact on Pyruvate Dehydrogenase Complex-E1 Structure and Function. J Chem Inf Model 2022; 62:3463-3475. [PMID: 35797142 DOI: 10.1021/acs.jcim.2c00630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pyruvate dehydrogenase complex (PDC) deficiency is a major cause of primary lactic acidemia resulting in high morbidity and mortality, with limited therapeutic options. The E1 component of the mitochondrial multienzyme PDC (PDC-E1) is a symmetric dimer of heterodimers (αβ/α'β') encoded by the PDHA1 and PDHB genes, with two symmetric active sites each consisting of highly conserved phosphorylation loops A and B. PDHA1 mutations are responsible for 82-88% of cases. Greater than 85% of E1α residues with disease-causing missense mutations (DMMs) are solvent-inaccessible, with ∼30% among those involved in subunit-subunit interface contact (SSIC). We performed molecular dynamics simulations of wild-type (WT) PDC-E1 and E1 variants with E1α DMMs at R349 and W185 (residues involved in SSIC), to investigate their impact on human PDC-E1 structure. We evaluated the change in E1 structure and dynamics and examined their implications on E1 function with the specific DMMs. We found that the dynamics of phosphorylation Loop A, which is crucial for E1 biological activity, changes with DMMs that are at least about 15 Å away. Because communication is essential for PDC-E1 activity (with alternating active sites), we also investigated the possible communication network within WT PDC-E1 via centrality analysis. We observed that DMMs altered/disrupted the communication network of PDC-E1. Collectively, these results indicate allosteric effect in PDC-E1, with implications for the development of novel small-molecule therapeutics for specific recurrent E1α DMMs such as replacements of R349 responsible for ∼10% of PDC deficiency due to E1α DMMs.
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Affiliation(s)
- Hatice Gokcan
- Department of Chemistry, Mellon College of Science, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Jirair K Bedoyan
- Division of Genetic and Genomic Medicine, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania 15224, United States.,Department of Pediatrics, University of Pittsburgh, Pittsburgh, Pennsylvania 15219, United States
| | - Olexandr Isayev
- Department of Chemistry, Mellon College of Science, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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Liu Y, Yang L, Liu P, Jin Y, Qin S, Chen L. Identification of Antibacterial Components in the Methanol-Phase Extract from Edible Herbaceous Plant Rumex madaio Makino and Their Antibacterial Action Modes. Molecules 2022; 27:molecules27030660. [PMID: 35163925 PMCID: PMC8839378 DOI: 10.3390/molecules27030660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 02/04/2023] Open
Abstract
Outbreaks and prevalence of infectious diseases worldwide are some of the major contributors to morbidity and morbidity in humans. Pharmacophageous plants are the best source for searching antibacterial compounds with low toxicity to humans. In this study, we identified, for the first time, antibacterial components and action modes of methanol-phase extract from such one edible herbaceous plant Rumex madaio Makino. The bacteriostatic rate of the extract was 75% against 23 species of common pathogenic bacteria. The extract was further purified using the preparative high-performance liquid chromatography (Prep-HPLC) technique, and five separated componential complexes (CC) were obtained. Among these, the CC 1 significantly increased cell surface hydrophobicity and membrane permeability and decreased membrane fluidity, which damaged cell structure integrity of Gram-positive and -negative pathogens tested. A total of 58 different compounds in the extract were identified using ultra-HPLC and mass spectrometry (UHPLC-MS) techniques. Comparative transcriptomic analyses revealed a number of differentially expressed genes and various changed metabolic pathways mediated by the CC1 action, such as down-regulated carbohydrate transport and/or utilization and energy metabolism in four pathogenic strains tested. Overall, the results in this study demonstrated that the CC1 from R. madaio Makino are promising candidates for antibacterial medicine and human health care products.
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Affiliation(s)
- Yue Liu
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs of the People’s Republic of China, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (L.Y.); (P.L.); (Y.J.)
| | - Lianzhi Yang
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs of the People’s Republic of China, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (L.Y.); (P.L.); (Y.J.)
| | - Pingping Liu
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs of the People’s Republic of China, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (L.Y.); (P.L.); (Y.J.)
| | - Yinzhe Jin
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs of the People’s Republic of China, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (L.Y.); (P.L.); (Y.J.)
| | - Si Qin
- Key Laboratory for Food Science and Biotechnology of Hunan Province, College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China
- Correspondence: (S.Q.); (L.C.)
| | - Lanming Chen
- Key Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs of the People’s Republic of China, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China; (Y.L.); (L.Y.); (P.L.); (Y.J.)
- Correspondence: (S.Q.); (L.C.)
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Pavlu-Pereira H, Lousa D, Tomé CS, Florindo C, Silva MJ, de Almeida IT, Leandro P, Rivera I, Vicente JB. Structural and functional impact of clinically relevant E1α variants causing pyruvate dehydrogenase complex deficiency. Biochimie 2021; 183:78-88. [PMID: 33588022 DOI: 10.1016/j.biochi.2021.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 01/19/2023]
Abstract
Pyruvate dehydrogenase complex (PDC) catalyzes the oxidative decarboxylation of pyruvate to acetyl-coenzyme A, hinging glycolysis and the tricarboxylic acid cycle. PDC deficiency, an inborn error of metabolism, has a broad phenotypic spectrum. Symptoms range from fatal lactic acidosis or progressive neuromuscular impairment in the neonatal period, to chronic neurodegeneration. Most disease-causing mutations in PDC deficiency affect the PDHA1 gene, encoding the α subunit of the PDC-E1 component. Detailed biophysical analysis of pathogenic protein variants is a challenging approach to support the design of therapies based on improving and correcting protein structure and function. Herein, we report the characterization of clinically relevant PDC-E1α variants identified in Portuguese PDC deficient patients. These variants bear amino acid substitutions in different structural regions of PDC-E1α. The structural and functional analyses of recombinant heterotetrameric (αα'ββ') PDC-E1 variants, combined with molecular dynamics (MD) simulations, show a limited impact of the amino acid changes on the conformational stability, apart from the increased propensity for aggregation of the p.R253G variant as compared to wild-type PDC-E1. However, all variants presented a functional impairment in terms of lower residual PDC-E1 enzymatic activity and ≈3-100 × lower affinity for the thiamine pyrophosphate (TPP) cofactor, in comparison with wild-type PDC-E1. MD simulations neatly showed generally decreased stability (increased flexibility) of all variants with respect to the WT heterotetramer, particularly in the TPP binding region. These results are discussed in light of disease severity of the patients bearing such mutations and highlight the difficulty of developing chaperone-based therapies for PDC deficiency.
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Affiliation(s)
- Hana Pavlu-Pereira
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Diana Lousa
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Catarina S Tomé
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Cristina Florindo
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Maria João Silva
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Isabel Tavares de Almeida
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Paula Leandro
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal.
| | - Isabel Rivera
- Research Institute for Medicines (iMed.ULisboa) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal.
| | - João B Vicente
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.
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7
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Pavlu-Pereira H, Silva MJ, Florindo C, Sequeira S, Ferreira AC, Duarte S, Rodrigues AL, Janeiro P, Oliveira A, Gomes D, Bandeira A, Martins E, Gomes R, Soares S, Tavares de Almeida I, Vicente JB, Rivera I. Pyruvate dehydrogenase complex deficiency: updating the clinical, metabolic and mutational landscapes in a cohort of Portuguese patients. Orphanet J Rare Dis 2020; 15:298. [PMID: 33092611 PMCID: PMC7579914 DOI: 10.1186/s13023-020-01586-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 10/13/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The pyruvate dehydrogenase complex (PDC) catalyzes the irreversible decarboxylation of pyruvate into acetyl-CoA. PDC deficiency can be caused by alterations in any of the genes encoding its several subunits. The resulting phenotype, though very heterogeneous, mainly affects the central nervous system. The aim of this study is to describe and discuss the clinical, biochemical and genotypic information from thirteen PDC deficient patients, thus seeking to establish possible genotype-phenotype correlations. RESULTS The mutational spectrum showed that seven patients carry mutations in the PDHA1 gene encoding the E1α subunit, five patients carry mutations in the PDHX gene encoding the E3 binding protein, and the remaining patient carries mutations in the DLD gene encoding the E3 subunit. These data corroborate earlier reports describing PDHA1 mutations as the predominant cause of PDC deficiency but also reveal a notable prevalence of PDHX mutations among Portuguese patients, most of them carrying what seems to be a private mutation (p.R284X). The biochemical analyses revealed high lactate and pyruvate plasma levels whereas the lactate/pyruvate ratio was below 16; enzymatic activities, when compared to control values, indicated to be independent from the genotype and ranged from 8.5% to 30%, the latter being considered a cut-off value for primary PDC deficiency. Concerning the clinical features, all patients displayed psychomotor retardation/developmental delay, the severity of which seems to correlate with the type and localization of the mutation carried by the patient. The therapeutic options essentially include the administration of a ketogenic diet and supplementation with thiamine, although arginine aspartate intake revealed to be beneficial in some patients. Moreover, in silico analysis of the missense mutations present in this PDC deficient population allowed to envisage the molecular mechanism underlying these pathogenic variants. CONCLUSION The identification of the disease-causing mutations, together with the functional and structural characterization of the mutant protein variants, allow to obtain an insight on the severity of the clinical phenotype and the selection of the most appropriate therapy.
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Affiliation(s)
- Hana Pavlu-Pereira
- Metabolism and Genetics Group, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisboa, Portugal
| | - Maria João Silva
- Metabolism and Genetics Group, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisboa, Portugal
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal
| | - Cristina Florindo
- Metabolism and Genetics Group, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisboa, Portugal
| | - Sílvia Sequeira
- Department of Pediatrics, Hospital D. Estefânia, Lisbon, Portugal
| | | | - Sofia Duarte
- Department of Pediatrics, Hospital D. Estefânia, Lisbon, Portugal
| | | | - Patrícia Janeiro
- Department of Pediatrics, Hospital Santa Maria, Lisbon, Portugal
| | | | - Daniel Gomes
- Department of Medicine, Hospital Santa Maria, Lisbon, Portugal
| | - Anabela Bandeira
- Department of Pediatrics, Hospital Santo António, Porto, Portugal
| | | | - Roseli Gomes
- Department of Neuropediatrics, Hospital Pedro Hispano, Matosinhos, Portugal
| | - Sérgia Soares
- Department of Neuropediatrics, Hospital Pedro Hispano, Matosinhos, Portugal
| | - Isabel Tavares de Almeida
- Metabolism and Genetics Group, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisboa, Portugal
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal
| | - João B Vicente
- Instituto de Tecnologia Química e Biológica António Xavier, NOVA University of Lisbon, Av. da República (Estação Agronómica Nacional), 2780-157, Oeiras, Portugal.
| | - Isabel Rivera
- Metabolism and Genetics Group, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisboa, Portugal.
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de Lisboa, Lisboa, Portugal.
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8
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Skalidis I, Tüting C, Kastritis PL. Unstructured regions of large enzymatic complexes control the availability of metabolites with signaling functions. Cell Commun Signal 2020; 18:136. [PMID: 32843078 PMCID: PMC7448341 DOI: 10.1186/s12964-020-00631-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/17/2020] [Indexed: 12/23/2022] Open
Abstract
Metabolites produced via traditional biochemical processes affect intracellular communication, inflammation, and malignancy. Unexpectedly, acetyl-CoA, α-ketoglutarate and palmitic acid, which are chemical species of reactions catalyzed by highly abundant, gigantic enzymatic complexes, dubbed as "metabolons", have broad "nonmetabolic" signaling functions. Conserved unstructured regions within metabolons determine the yield of these metabolites. Unstructured regions tether functional protein domains, act as spatial constraints to confine constituent enzyme communication, and, in the case of acetyl-CoA production, tend to be regulated by intricate phosphorylation patterns. This review presents the multifaceted roles of these three significant metabolites and describes how their perturbation leads to altered or transformed cellular function. Their dedicated enzymatic systems are then introduced, namely, the pyruvate dehydrogenase (PDH) and oxoglutarate dehydrogenase (OGDH) complexes, and the fatty acid synthase (FAS), with a particular focus on their structural characterization and the localization of unstructured regions. Finally, upstream metabolite regulation, in which spatial occupancy of unstructured regions within dedicated metabolons may affect metabolite availability and subsequently alter cell functions, is discussed. Video abstract.
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Affiliation(s)
- Ioannis Skalidis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany.,Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, Halle/Saale, Germany
| | - Christian Tüting
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany.,Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, Halle/Saale, Germany
| | - Panagiotis L Kastritis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3a, Halle/Saale, Germany. .,Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Straße 3, Halle/Saale, Germany. .,ZIK HALOmem, Martin Luther University Halle-Wittenberg, Biozentrum, Room A.2.14, Weinbergweg 22, 06120, Halle/Saale, Germany.
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