Combination of Brain MRI Features As a Useful Tool for Genotype/Phe

Total Page:16

File Type:pdf, Size:1020Kb

Combination of Brain MRI Features As a Useful Tool for Genotype/Phe Downloaded from jmg.bmj.com on June 17, 2014 - Published by group.bmj.com JMG Online First, published on May 1, 2014 as 10.1136/jmedgenet-2013-102256 Review Brain imaging in mitochondrial respiratory chain deficiency: combination of brain MRI features as a useful tool for genotype/phenotype correlations M Bricout,1 D Grévent,1 A S Lebre,2 M Rio,2 I Desguerre,3 P De Lonlay,3 V Valayannopoulos,3 F Brunelle,1 A Rötig,2 A Munnich,2 N Boddaert1 1Department of Pediatric ABSTRACT COMPLEX I DEFICIENCY Radiology, Hôpital Necker- Mitochondrial diseases are characterised by a broad Isolated complex I deficiency, the most frequent Enfants Malades and Inserm U781 and U1000, Université clinical and genetic heterogeneity that makes diagnosis cause of respiratory chain defects in childhood, Paris Descartes-Sorbonne Paris difficult. Owing to the wide pattern of symptoms in accounts for various clinical presentations combin- Cité, Institut Imagine, Paris, mitochondrial disorders and the constantly growing ing hypotonia, developmental delay, seizures, car- France 2 number of disease genes, their genetic diagnosis is diomyopathy, optic atrophy or retinopathy and Department of Genetic Units, difficult and genotype/phenotype correlations remain other organ involvement. It includes Leigh syn- Hôpital Necker-Enfants Malades and Inserm U781 and elusive. Brain MRI appears as a useful tool for genotype/ drome, Leber hereditary optic neuropathy (LHON), U1000, Université Paris phenotype correlations. Here, we summarise the various mitochondrial encephalomyopathy, lactic acidosis Descartes-Sorbonne Paris Cité, combinations of MRI lesions observed in the most and stroke-like episodes (MELAS) and numerous Institut Imagine, Paris, France frequent mitochondrial respiratory chain deficiencies so other clinical presentations. Leigh syndrome is an 3Department of Neurology, Hôpital Necker-Enfants as to direct molecular genetic test in patients at risk of early-onset progressive neurodegenerative disorder Malades and Inserm U781 and such diseases. We believe that the combination of brain causing various symptoms, including hypotonia, U1000, Université Paris MRI features is of value to support respiratory chain psychomotor regression, ataxia, ocular movement Descartes-Sorbonne Paris Cité, deficiency and direct molecular genetic tests. abnormalities, seizures, dystonia, swallowing dys- Institut Imagine, Paris, France function and respiratory disturbances. Characteristic Correspondence to neuropathological features consist of spongiform Dr M Bricout, Department of Mitochondrial diseases are due to deficiency of the necrosis, myelin degeneration, vascular proliferation Pediatric radiology, Hôpital respiratory chain, which is made up of five com- and gliosis in one or more areas of the central Necker-Enfants Malades and plexes and consists of more than 80 different pro- nervous system (CNS), including thalamus, basal Inserm U781 and U1000, 1 Université Paris Descartes- teins. These diseases are characterised by a broad ganglia, brainstem and spinal cord. Sorbonne Paris Cité, Institut clinical and genetic heterogeneity that makes diag- Complex I (NADH:ubiquinone oxidoreductase), Imagine, 149 rue de sèvres, nosis difficult. Some clinical presentations are highly the largest component of the respiratory chain, Paris 75015, France; marine. suggestive of given gene mutations, allowing rapid comprises seven core subunits encoded by mitochon- [email protected] genetic diagnosis. However, owing to the wide drial DNA (mtDNA), 38 nuclearly encoded core Received 17 January 2014 pattern of symptoms in mitochondrial disorders and subunits and few known (but many unknown) assem- Revised 17 March 2014 the constantly growing number of disease genes, bly factors. To date, disease causing mutations have Accepted 6 April 2014 their genetic diagnosis is frequently difficult and been identified in 19 core subunits comprising 16 genotype/phenotype correlations remain elusive. nuclear genes (NDUFS1-4, NDUFS6-8, NDUFV1-2, Here, based on brain MRI features in known NDUFA1-2, NDUFA9-11, NDUFB3,9), 7 mtDNA nuclear/mitochondrial DNA mutations, we have genes and at least 6 assembly factors (NDUFAF1-4, tried to provide physicians with valuable informa- NUBPL, C8orf38 and C20orf7). Our retrospective tion so as to help them in interpreting the growing study of brain MRI and/or CT-scan in 30 complex amount of data derived from exome sequencing I-deficient patients carrying known mutations have and targeted gene resequencing in mitochondrial helped us identify a consistent pattern of brain MRI diseases. imaging in primary complex I deficiency.2 Indeed, we Based on the current review of published litera- observed a common and uniform pattern of bilateral ture, we have focused our MRI analysis for the and symmetrical brainstem lesions in 30/30 complex genotype/phenotype correlations on five brain areas I-deficient patients (table 1). Putaminal anomalies known as targets of mitochondrial dysfunction: (1) were very frequent (23/30). Supra-tentorial stroke- basal ganglia (hyperintensities on T2-weighted like lesions were only observed in patients carrying imaging or calcifications); (2) cerebellum (hyperin- mtDNA mutations (8/19) while necrotising leucoen- tensities on T2 or atrophy); (3) brainstem (hyperin- cephalopathy was constantly found in patients carry- tensities on T2 or atrophy); (4) white matter ing nDNA mutations (4/5). Cerebellar atrophy was (leucoencephalopathy); (5) cortex (supra-tentorial observed in 9/12 patients older than 5 years and car- atrophy). Stroke-like episodes were also considered. rying mtDNA mutation (75%) but neither below The combination of some features and absence of 5 years nor in patients carrying nDNA mutations.2 others are sometimes suggestive of a particular Interestingly, hyperintensity of coliculli was often To cite: Bricout M, respiratory chain deficiency or gene mutation. We encountered in patients in mt-ND5 mutation.3 Grévent D, Lebre AS, et al. J NUBPL Med Genet Published Online believe that the combination of brain MRI anomal- mutations caused major abnormalities of First: [please include Day ies is of value to support respiratory chain defi- the cerebellum and inconstant supra-tentorial leu- Month Year] doi:10.1136/ ciency and interpret next-generation sequencing coencephalopathy involvement but no anomalies of jmedgenet-2013-102256 data in respiratory chain deficiency. the basal ganglia45(figure 1). BricoutCopyright M, et al. J MedArticle Genet 2014;author0:1–7. (or doi:10.1136/jmedgenet-2013-102256 their employer) 2014. Produced by BMJ Publishing Group Ltd under licence. 1 Downloaded from jmg.bmj.com on June 17, 2014 - Published by group.bmj.com Review Table 1 Various combinations of MRI abnormalities observed in the most frequent mitochondrial respiratory chain deficiencies Respiratory chain deficiency Basal ganglia Cerebellum Brainstem Leucoencephalopathy Cortical atrophy Stroke-like episodes Complex I mitochondrial DNA ± ± + −−± Complex I nuclear DNA ± ± + ± −− NUBPL − +±± −− SURF1 ± ± ± ± −− Complex V + ± ± −−− PDH deficiency ± ± ± −−− SUCLG1/SUCLA2 + −−− ± − Ubiquinone deficiency − + −− − ± MELAS ± ± −− ±± POLG ± ± −− ±± Kearns–Sayre syndrome ± ± ± ± ± ± RARS2 − ++− + − FARS2 + −−− + − DARS2 − ±++ −− EARS2 ± ± ± + −− MNGIE ± ± ± + −− MEALS, Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes; MNGIE, Mitochondrial Neurogastrointestinal Encephalopathy. Hence, complex I mtDNA mutations consistently caused COMPLEX V DEFICIENCY brainstem±basal ganglia involvement±stroke-like episodes Complex V deficiency is a rare cause of respiratory chain defi- ±cerebellar atrophy involvement while nuclear complex I muta- ciency. Clinical presentations include neuropathy, ataxia and retin- tions caused brainstem±basal ganglia involvement±leucoence- itis pigmentosa (NARP) and Leigh syndrome. The most frequent phalopathy (figures 2 and 3). Complex I deficiency is unlikely if known cause of complex V deficiency is the MT-ATP6 gene muta- no brainstem involvement is observed. tion. Those patients present MRI lesions involving basal ganglia frequently associated with cerebellar atrophy (table 1).67 Associated brainstem lesions are observed in largely 25% of cases. No stroke-like lesions, delayed myelination or corpus callosum abnormalities were noted in patients carrying MT-ATP6 mutations. Few patients carrying mutant genotypes other than MT- ATP6-ATP8 mutation have been reported. Jonckheere et al8 reported no brain lesion but a cisterna magna in a patient carrying a MT-ATP8 mutation. Finally, brain MRI of TMEM70 patients showed prominent cerebellar and pontine atrophy, generalised cor- tical atrophy, hypoplastic corpus callosum and relative white matter deficiency.9 Hence, brain MRI features in MT-ATP6 mutations involved basal ganglia±brainstem and cerebellar atrophy (figure 4). CYTOCHROME C OXIDASE DEFICIENCY SURF1 is the first assembly factor gene reported to cause cyto- chrome c oxidase (COX) deficiency. Leigh syndrome is the most common clinical manifestation of SURF1 mutation, but milder neurological involvement with a malabsorption syndrome or leucoencephalopathy has been described.10 Mutations in three other COX assembly genes, COX10, SCO1 and SCO2, are asso- ciated with hypertrophic cardiomyopathy and encephalopathy combined with hepatic failure. Hitherto, two major brain MRI features were observed in COX deficiency, namely, diffuse leucoencephalopathy (corpus callosum, internal capsule, cerebellar white matter and U fibres) and/or brainstem involve- ment. Abnormal white
Recommended publications
  • Remodeling Adipose Tissue Through in Silico Modulation of Fat Storage For
    Chénard et al. BMC Systems Biology (2017) 11:60 DOI 10.1186/s12918-017-0438-9 RESEARCHARTICLE Open Access Remodeling adipose tissue through in silico modulation of fat storage for the prevention of type 2 diabetes Thierry Chénard2, Frédéric Guénard3, Marie-Claude Vohl3,4, André Carpentier5, André Tchernof4,6 and Rafael J. Najmanovich1* Abstract Background: Type 2 diabetes is one of the leading non-infectious diseases worldwide and closely relates to excess adipose tissue accumulation as seen in obesity. Specifically, hypertrophic expansion of adipose tissues is related to increased cardiometabolic risk leading to type 2 diabetes. Studying mechanisms underlying adipocyte hypertrophy could lead to the identification of potential targets for the treatment of these conditions. Results: We present iTC1390adip, a highly curated metabolic network of the human adipocyte presenting various improvements over the previously published iAdipocytes1809. iTC1390adip contains 1390 genes, 4519 reactions and 3664 metabolites. We validated the network obtaining 92.6% accuracy by comparing experimental gene essentiality in various cell lines to our predictions of biomass production. Using flux balance analysis under various test conditions, we predict the effect of gene deletion on both lipid droplet and biomass production, resulting in the identification of 27 genes that could reduce adipocyte hypertrophy. We also used expression data from visceral and subcutaneous adipose tissues to compare the effect of single gene deletions between adipocytes from each
    [Show full text]
  • Two Transgenic Mouse Models for Β-Subunit Components of Succinate-Coa Ligase Yielding Pleiotropic Metabolic Alterations
    Two transgenic mouse models for -subunit components of succinate-CoA ligase yielding pleiotropic metabolic alterations Kacso, Gergely; Ravasz, Dora; Doczi, Judit; Németh, Beáta; Madgar, Ory; Saada, Ann; Ilin, Polina; Miller, Chaya; Ostergaard, Elsebet; Iordanov, Iordan; Adams, Daniel; Vargedo, Zsuzsanna; Araki, Masatake; Araki, Kimi; Nakahara, Mai; Ito, Haruka; Gál, Aniko; Molnár, Mária J; Nagy, Zsolt; Patocs, Attila; Adam-Vizi, Vera; Chinopoulos, Christos Published in: Biochemical Journal DOI: 10.1042/BCJ20160594 Publication date: 2016 Document version Publisher's PDF, also known as Version of record Document license: CC BY Citation for published version (APA): Kacso, G., Ravasz, D., Doczi, J., Németh, B., Madgar, O., Saada, A., Ilin, P., Miller, C., Ostergaard, E., Iordanov, I., Adams, D., Vargedo, Z., Araki, M., Araki, K., Nakahara, M., Ito, H., Gál, A., Molnár, M. J., Nagy, Z., ... Chinopoulos, C. (2016). Two transgenic mouse models for -subunit components of succinate-CoA ligase yielding pleiotropic metabolic alterations. Biochemical Journal, 473(20), 3463-3485. https://doi.org/10.1042/BCJ20160594 Download date: 02. okt.. 2021 Biochemical Journal (2016) 473 3463–3485 DOI: 10.1042/BCJ20160594 Research Article Two transgenic mouse models for β-subunit components of succinate-CoA ligase yielding pleiotropic metabolic alterations Gergely Kacso1,2, Dora Ravasz1,2, Judit Doczi1,2, Beáta Németh1,2, Ory Madgar1,2, Ann Saada3, Polina Ilin3, Chaya Miller3, Elsebet Ostergaard4, Iordan Iordanov1,5, Daniel Adams1,2, Zsuzsanna Vargedo1,2, Masatake
    [Show full text]
  • Complex I Deficiency Due to Loss of Ndufs4 in the Brain Results
    Complex I deficiency due to loss of Ndufs4 in the brain results in progressive encephalopathy resembling Leigh syndrome Albert Quintanaa,1, Shane E. Krusea,1, Raj P. Kapurb, Elisenda Sanzc, and Richard D. Palmitera,2 aHoward Hughes Medical Institute and Department of Biochemistry, University of Washington, Seattle, WA 98195; bDepartment of Laboratories, Seattle Children’s Hospital, Seattle, WA 98105; and cDepartment of Pharmacology, University of Washington, Seattle, WA 98195 Contributed by Richard D. Palmiter, May 5, 2010 (sent for review April 22, 2010) To explore the lethal, ataxic phenotype of complex I deficiency in least one intact Ndufs4 allele are indistinguishable from WT Ndufs4 knockout (KO) mice, we inactivated Ndufs4 selectively in mice, and they are sometimes used interchangeably with WT as neurons and glia (NesKO mice). NesKO mice manifested the same controls (CT). To examine the role of the CNS in pathology, we symptoms as KO mice including retarded growth, loss of motor restricted the inactivation of Ndufs4 gene to neurons and lox/lox ability, breathing abnormalities, and death by ∼7 wk. Progressive astroglial cells by crossing the Ndufs4 mice with mice neuronal deterioration and gliosis in specific brain areas corre- expressing Cre recombinase from the Nestin locus (19) to create sponded to behavioral changes as the disease advanced, with mice that we refer to as NesKO mice. We confirmed that Nestin- early involvement of the olfactory bulb, cerebellum, and vestibular Cre results in recombination primarily in the CNS by crossing the nuclei. Neurons, particularly in these brain regions, had aberrant mice with a Rosa26-reporter line and by PCR analysis of DNA mitochondrial morphology.
    [Show full text]
  • Multi-Targeted Mechanisms Underlying the Endothelial Protective Effects of the Diabetic-Safe Sweetener Erythritol
    Multi-Targeted Mechanisms Underlying the Endothelial Protective Effects of the Diabetic-Safe Sweetener Erythritol Danie¨lle M. P. H. J. Boesten1*., Alvin Berger2.¤, Peter de Cock3, Hua Dong4, Bruce D. Hammock4, Gertjan J. M. den Hartog1, Aalt Bast1 1 Department of Toxicology, Maastricht University, Maastricht, The Netherlands, 2 Global Food Research, Cargill, Wayzata, Minnesota, United States of America, 3 Cargill RandD Center Europe, Vilvoorde, Belgium, 4 Department of Entomology and UCD Comprehensive Cancer Center, University of California Davis, Davis, California, United States of America Abstract Diabetes is characterized by hyperglycemia and development of vascular pathology. Endothelial cell dysfunction is a starting point for pathogenesis of vascular complications in diabetes. We previously showed the polyol erythritol to be a hydroxyl radical scavenger preventing endothelial cell dysfunction onset in diabetic rats. To unravel mechanisms, other than scavenging of radicals, by which erythritol mediates this protective effect, we evaluated effects of erythritol in endothelial cells exposed to normal (7 mM) and high glucose (30 mM) or diabetic stressors (e.g. SIN-1) using targeted and transcriptomic approaches. This study demonstrates that erythritol (i.e. under non-diabetic conditions) has minimal effects on endothelial cells. However, under hyperglycemic conditions erythritol protected endothelial cells against cell death induced by diabetic stressors (i.e. high glucose and peroxynitrite). Also a number of harmful effects caused by high glucose, e.g. increased nitric oxide release, are reversed. Additionally, total transcriptome analysis indicated that biological processes which are differentially regulated due to high glucose are corrected by erythritol. We conclude that erythritol protects endothelial cells during high glucose conditions via effects on multiple targets.
    [Show full text]
  • Remodeling Adipose Tissue Through in Silico Modulation of Fat Storage For
    Chénard et al. BMC Systems Biology (2017) 11:60 DOI 10.1186/s12918-017-0438-9 RESEARCHARTICLE Open Access Remodeling adipose tissue through in silico modulation of fat storage for the prevention of type 2 diabetes Thierry Chénard2, Frédéric Guénard3, Marie-Claude Vohl3,4, André Carpentier5, André Tchernof4,6 and Rafael J. Najmanovich1* Abstract Background: Type 2 diabetes is one of the leading non-infectious diseases worldwide and closely relates to excess adipose tissue accumulation as seen in obesity. Specifically, hypertrophic expansion of adipose tissues is related to increased cardiometabolic risk leading to type 2 diabetes. Studying mechanisms underlying adipocyte hypertrophy could lead to the identification of potential targets for the treatment of these conditions. Results: We present iTC1390adip, a highly curated metabolic network of the human adipocyte presenting various improvements over the previously published iAdipocytes1809. iTC1390adip contains 1390 genes, 4519 reactions and 3664 metabolites. We validated the network obtaining 92.6% accuracy by comparing experimental gene essentiality in various cell lines to our predictions of biomass production. Using flux balance analysis under various test conditions, we predict the effect of gene deletion on both lipid droplet and biomass production, resulting in the identification of 27 genes that could reduce adipocyte hypertrophy. We also used expression data from visceral and subcutaneous adipose tissues to compare the effect of single gene deletions between adipocytes from each
    [Show full text]
  • Mitochondrial Hepatopathies Etiology and Genetics the Hepatocyte Mitochondrion Can Function Both As a Cause and As a Target of Liver Injury
    Mitochondrial Hepatopathies Etiology and Genetics The hepatocyte mitochondrion can function both as a cause and as a target of liver injury. Most mitochondrial hepatopathies involve defects in the mitochondrial respiratory chain enzyme complexes (Figure 1). Resultant dysfunction of mitochondria yields deficient oxidative phosphorylation (OXPHOS), increased generation of reactive oxygen species (ROS), accumulation of hepatocyte lipid, impairment of other metabolic pathways and activation of both apoptotic and necrotic pathways of cellular death. Figure 1: Since the mitochondria are under dual control of nuclear DNA and mitochondrial DNA (mtDNA), mutations in genes of both classes have been associated with inherited mitochondrial myopathies, encephalopathies, and hepatopathies. Autosomal nuclear gene defects affect a variety of mitochondrial processes such as protein assembly, mtDNA synthesis and replication (e.g., deoxyguanosine kinase [dGUOK]) and DNA polymerase gamma [POLG]), and transport of nucleotides or metals. MPV17 (function unknown) and RRM2B (encoding the cytosolic p53-inducible ribonucleotide reductase small subunit) are two genes recently identified as also causing mtDNA depletion syndrome and liver failure, as has TWINKLE, TRMU, and SUCLG1. Most children with mitochondrial hepatopathies have identified or presumed mutations in these nuclear genes, rather than mtDNA genes. A classification of primary mitochondrial hepatopathies involving energy metabolism is presented in Table 1. Drug interference with mtDNA replication is now recognized as a cause of acquired mtDNA depletion that can result in liver failure, lactic acidosis, and myopathy in human immunodeficiency virus infected patients and, previously, in hepatitis B virus patients treated with nucleoside reverse transcriptase inhibitors. Current estimates suggest a minimum prevalence of all mitochondrial diseases of 11.5 cases per 100,000 individuals, or 1 in 8500 of the general population.
    [Show full text]
  • A High-Throughput Approach to Uncover Novel Roles of APOBEC2, a Functional Orphan of the AID/APOBEC Family
    Rockefeller University Digital Commons @ RU Student Theses and Dissertations 2018 A High-Throughput Approach to Uncover Novel Roles of APOBEC2, a Functional Orphan of the AID/APOBEC Family Linda Molla Follow this and additional works at: https://digitalcommons.rockefeller.edu/ student_theses_and_dissertations Part of the Life Sciences Commons A HIGH-THROUGHPUT APPROACH TO UNCOVER NOVEL ROLES OF APOBEC2, A FUNCTIONAL ORPHAN OF THE AID/APOBEC FAMILY A Thesis Presented to the Faculty of The Rockefeller University in Partial Fulfillment of the Requirements for the degree of Doctor of Philosophy by Linda Molla June 2018 © Copyright by Linda Molla 2018 A HIGH-THROUGHPUT APPROACH TO UNCOVER NOVEL ROLES OF APOBEC2, A FUNCTIONAL ORPHAN OF THE AID/APOBEC FAMILY Linda Molla, Ph.D. The Rockefeller University 2018 APOBEC2 is a member of the AID/APOBEC cytidine deaminase family of proteins. Unlike most of AID/APOBEC, however, APOBEC2’s function remains elusive. Previous research has implicated APOBEC2 in diverse organisms and cellular processes such as muscle biology (in Mus musculus), regeneration (in Danio rerio), and development (in Xenopus laevis). APOBEC2 has also been implicated in cancer. However the enzymatic activity, substrate or physiological target(s) of APOBEC2 are unknown. For this thesis, I have combined Next Generation Sequencing (NGS) techniques with state-of-the-art molecular biology to determine the physiological targets of APOBEC2. Using a cell culture muscle differentiation system, and RNA sequencing (RNA-Seq) by polyA capture, I demonstrated that unlike the AID/APOBEC family member APOBEC1, APOBEC2 is not an RNA editor. Using the same system combined with enhanced Reduced Representation Bisulfite Sequencing (eRRBS) analyses I showed that, unlike the AID/APOBEC family member AID, APOBEC2 does not act as a 5-methyl-C deaminase.
    [Show full text]
  • SUCLA2 Mutations Cause Global Protein Succinylation Contributing To
    ARTICLE https://doi.org/10.1038/s41467-020-19743-4 OPEN SUCLA2 mutations cause global protein succinylation contributing to the pathomechanism of a hereditary mitochondrial disease ✉ Philipp Gut 1,2,17 , Sanna Matilainen3,17, Jesse G. Meyer4,14,17, Pieti Pällijeff3, Joy Richard2, Christopher J. Carroll5, Liliya Euro 3, Christopher B. Jackson 3, Pirjo Isohanni3,6, Berge A. Minassian7,8, Reem A. Alkhater9, Elsebet Østergaard10, Gabriele Civiletto2, Alice Parisi2, Jonathan Thevenet2, Matthew J. Rardin4,15, Wenjuan He1, Yuya Nishida1, John C. Newman 1, Xiaojing Liu11,16, Stefan Christen2, ✉ ✉ Sofia Moco 2, Jason W. Locasale 11, Birgit Schilling 4,18 , Anu Suomalainen 3,12,13,18 & 1234567890():,; ✉ Eric Verdin 1,4,18 Mitochondrial acyl-coenzyme A species are emerging as important sources of protein modification and damage. Succinyl-CoA ligase (SCL) deficiency causes a mitochondrial encephalomyopathy of unknown pathomechanism. Here, we show that succinyl-CoA accumulates in cells derived from patients with recessive mutations in the tricarboxylic acid cycle (TCA) gene succinyl-CoA ligase subunit-β (SUCLA2), causing global protein hyper- succinylation. Using mass spectrometry, we quantify nearly 1,000 protein succinylation sites on 366 proteins from patient-derived fibroblasts and myotubes. Interestingly, hyper- succinylated proteins are distributed across cellular compartments, and many are known targets of the (NAD+)-dependent desuccinylase SIRT5. To test the contribution of hyper- succinylation to disease progression, we develop a zebrafish model of the SCL deficiency and find that SIRT5 gain-of-function reduces global protein succinylation and improves survival. Thus, increased succinyl-CoA levels contribute to the pathology of SCL deficiency through post-translational modifications.
    [Show full text]
  • Exclusive Neuronal Expression of SUCLA2 in the Human Brain
    Exclusive neuronal expression of SUCLA2 in the human brain Arpád Dobolyi1, Elsebet Ostergaard2, Attila G. Bagó1,3, Tamás Dóczi4, Miklós Palkovits1,5, Aniko Gál6, Mária J Molnár6, Vera Adam-Vizi7 and Christos Chinopoulos7 1Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, 1094, Hungary; 2Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, Copenhagen, 2100, Denmark; 3National Institute of Neurosurgery, Budapest, 1145, Hungary; 4MTA-PTE Clinical MR Research Group, Department of Neurosurgery, University of Pécs, 7623, Pécs, Hungary; 5Human Brain Tissue Bank, Semmelweis University, Budapest, 1094, Hungary; 6Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, 1083, Hungary; 7Department of Medical Biochemistry, Semmelweis University, Hungarian Academy of Sciences-SE Laboratory for Neurobiochemistry, Budapest, 1094, Hungary Address correspondence to: Dr. Christos Chinopoulos, Department of Medical Biochemistry, Semmelweis University, Budapest, Hungary. Tel: +361 4591500 ext. 60024, Fax: +361 2670031. E-mail: [email protected] ABSTRACT SUCLA2 encodes the ATP-forming subunit (A-SUCL- ) of succinyl-CoA ligase, an enzyme of the citric acid cycle. Mutations in SUCLA2 lead to a mitochondrial disorder manifesting as encephalomyopathy with dystonia, deafness and lesions in the basal ganglia. Despite the distinct brain pathology associated with SUCLA2 mutations, the precise localization of SUCLA2 protein has never been investigated. Here we show that immunoreactivity of A-SUCL- in surgical human cortical tissue samples was present exclusively in neurons, identified by their morphology and visualized by double labeling with a fluorescent Nissl dye. A-SUCL- immunoreactivity co-localized >99% with that of the d subunit of the mitochondrial F0-F1 ATP synthase. Specificity of the anti-A-SUCL- antiserum was verified by the absence of labeling in fibroblasts from a patient with a complete deletion of SUCLA2.
    [Show full text]
  • Screen for Abnormal Mitochondrial Phenotypes in Mouse Embryonic Stem Cells Identifies a Model for Succinyl-Coa Ligase Deficiency and Mtdna Depletion Taraka R
    © 2014. Published by The Company of Biologists Ltd | Disease Models & Mechanisms (2014) 7, 271-280 doi:10.1242/dmm.013466 RESOURCE ARTICLE Screen for abnormal mitochondrial phenotypes in mouse embryonic stem cells identifies a model for succinyl-CoA ligase deficiency and mtDNA depletion Taraka R. Donti1,‡, Carmen Stromberger1,*,‡, Ming Ge1, Karen W. Eldin2, William J. Craigen1,3 and Brett H. Graham1,§ ABSTRACT prevalence of mitochondrial disorders might be as high as 1 in 5000, Mutations in subunits of succinyl-CoA synthetase/ligase (SCS), a making mitochondrial disease one of the more common genetic component of the citric acid cycle, are associated with mitochondrial causes of encephalomyopathies and multisystem disease (Schaefer et encephalomyopathy, elevation of methylmalonic acid (MMA), and al., 2004; Elliott et al., 2008; Schaefer et al., 2008). Despite important mitochondrial DNA (mtDNA) depletion. A FACS-based retroviral- insights into clinical, biochemical and molecular features of these mediated gene trap mutagenesis screen in mouse embryonic stem disorders, the underlying molecular pathogenesis remains poorly (ES) cells for abnormal mitochondrial phenotypes identified a gene understood and no clearly effective therapies exist. Mitochondria trap allele of Sucla2 (Sucla2SAβgeo), which was used to generate contain their own genome that consists of a multicopy, ~16.4-kilobase transgenic mice. Sucla2 encodes the ADP-specific β-subunit isoform circular chromosome. This mitochondrial DNA (mtDNA) encodes 13 of SCS. Sucla2SAβgeo homozygotes exhibited recessive lethality, with polypeptides that are subunits of various respiratory chain complexes most mutants dying late in gestation (e18.5). Mutant placenta and as well as 22 tRNAs and two rRNAs required for mitochondrial embryonic (e17.5) brain, heart and muscle showed varying degrees protein translation.
    [Show full text]
  • Succinyl-Coa Synthetase Deficiency in Siblings with Impaired Pyruvate Dehydrogenase Complex (PDC) and Other Oxidative
    Harvard Medical School Succinyl-CoA synthetase deficiency in siblings with impaired pyruvate dehydrogenase complex (PDC) and other oxidative Boston Children’s Hospital enzymes in skeletal muscle without mtDNA depletion Cleveland Medical Center Xiaoping Huanga,, Jirair K. Bedoyanb,c,d,j, Didem Demirbasa, David J. Harrisa,e, Alexander Mironc, Simone Edelheitc, George Grahamed, Suzanne D. DeBrossebc,j, Lee-Jun Wongf, Charles L. Hoppeld,g,h, Douglas S. Kerrd,j, Irina Anselmi, and Gerard T. Berrya,e a Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital (BCH), Boston, MA, USA; b Center for Human Genetics, University Hospitals Cleveland Medical Center (UHCMC), Cleveland, OH, USA; c Department of Genetics and Genome Sciences, Case Western Reserve University (CWRU), Cleveland, OH, USA; d Center for Inherited Disorders of Energy Metabolism (CIDEM), UHCMC, Cleveland, OH, USA; e Department of Pediatrics, Harvard Medical School, Boston, MA, USA; f Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; g Department of Pharmacology, CWRU, Cleveland, OH, USA; h Department of Medicine, CWRU, Cleveland, OH, USA; I Department of Neurology, BCH, Boston, MA USA; and j Department of Pediatrics, CWRU, Cleveland, OH, USA. SUMMARY These authors contributed equally to this work. Mutations in SUCLA2 result in succinyl-CoA ligase (ATP-forming) or succinyl-CoA synthetase (ADP-forming) (A-SCS) deficiency, a mitochondrial tricarboxylic acid cycle disorder (Fig. 1). The phenotype associated with this gene defect is largely encephalomyopathy. We describe two siblings compound heterozygous for SUCLA2 mutations, c.985A>G (p.M329V) and c.920C>T (p.A307V), with parents confirmed as carriers of each mutation.
    [Show full text]
  • Datasheet Blank Template
    SAN TA C RUZ BI OTEC HNOL OG Y, INC . SUCLA2 (H-296): sc-68912 BACKGROUND PRODUCT SUCLA2 (succinate-CoA ligase, ADP-forming, β subunit), also known as A- β, Each vial contains 200 µg IgG in 1.0 ml of PBS with < 0.1% sodium azide SCS- βA or renal carcinoma antigen NY-REN-39, is a 463 amino acid mito - and 0.1% gelatin. chondrial matrix enzyme that belongs to the succinate/malate CoA ligase β subunit family. Widely expressed, SUCLA2 dimerizes with the SCS α sub - APPLICATIONS unit to form SCS-A, an essential component of the tricarboxylic acid cycle. SUCLA2 (H-296) is recommended for detection of SUCLA2 of mouse, rat and Defects in SUCLA2 may be involved in a group of autosomal recessive disor - human origin by Western Blotting (starting dilution 1:200, dilution range ders known as mitochondrial DNA depletion syndromes (MDSs) that are 1:100-1:1000), immunoprecipitation [1-2 µg per 100-500 µg of total protein characterized by a decrease in mitochondrial DNA copy numbers in affected (1 ml of cell lysate)], immunofluorescence (starting dilution 1:50, dilution tissues. Progressive external ophthalmoplegia (PEO), ataxia-neuropathy and range 1:50-1:500) and solid phase ELISA (starting dilution 1:30, dilution range mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) may also be 1:30-1:3000). associated with mutations in SUCLA2. Two isoforms of SUCLA2 exists due to alternative splicing events. SUCLA2 (H-296) is also recommended for detection of SUCLA2 in additional species, including canine, bovine and porcine. REFERENCES Suitable for use as control antibody for SUCLA2 siRNA (h): sc-76598, SUCLA2 1.
    [Show full text]