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Pirrone MG, Gysin M, Haldimann K, Hobbie SN, Vasella A, Crich D. Predictive Analysis of the Side Chain Conformation of the Higher Carbon Sugars: Application to the Preorganization of the Aminoglycoside Ring 1 Side Chain for Binding to the Bacterial Ribosomal Decoding A Site. J Org Chem 2020; 85:16043-16059. [PMID: 32902280 PMCID: PMC7749010 DOI: 10.1021/acs.joc.0c01836] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
With a view to facilitating prediction of the exocyclic bond to the pyranoside ring in higher carbon sugars, a model is advanced that relates the relative configuration of the three stereogenic centers comprised of the branchpoint and of the two flanking centers (C4-C5-C6 in aldoheptoses and higher and C5-C6-C7 in sialic and ulosonic acids) to that of the simple ring-opened pentoses. Assignment of a given stereotriad as arabino, lxyo, ribo, or xylo by inspection of the Fischer projection formulas permits prediction of conformation of the exocyclic bond by comparison with the known solution (= crystal in all cases) conformations of the simple pentitols. More remote stereogenic centers in the side chain, as in the 8-position of N-acetylneuraminic acid, have little impact on the conformation of the exocyclic bond. On the basis of this model the conformation of the exocyclic bond in ring I of 6'-homologated 4,5-disubstituted 2-deoxystreptamine class aminoglycoside antibiotics was predicted and was borne out by NMR analysis of newly synthesized derivatives in D2O at pD5. The antiribosomal and antibacterial activity of these derivatives is briefly presented and discussed in terms of preorganization of the side chain for binding to the ribosomal decoding A site. It is anticipated that this predictive analysis will also find use in the prediction of the conformation of the exocyclic bonds in other 2-(1-hydroxyalkyl)-3-hydroxytetrahydropyrans and tetrahydrofurans.
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Affiliation(s)
- Michael G Pirrone
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, Georgia 30602, United States
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United States
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
| | - Marina Gysin
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 28, 8006 Zürich, Switzerland
| | - Klara Haldimann
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 28, 8006 Zürich, Switzerland
| | - Sven N Hobbie
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 28, 8006 Zürich, Switzerland
| | - Andrea Vasella
- Organic Chemistry Laboratory, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland
| | - David Crich
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, Georgia 30602, United States
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United States
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, United States
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
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2
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Clinical syndromes associated with mtDNA mutations: where we stand after 30 years. Essays Biochem 2018; 62:235-254. [DOI: 10.1042/ebc20170097] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 05/29/2018] [Accepted: 05/30/2018] [Indexed: 01/16/2023]
Abstract
The landmark year 1988 can be considered as the birthdate of mitochondrial medicine, when the first pathogenic mutations affecting mtDNA were associated with human diseases. Three decades later, the field still expands and we are not ‘scraping the bottom of the barrel’ yet. Despite the tremendous progress in terms of molecular characterization and genotype/phenotype correlations, for the vast majority of cases we still lack a deep understanding of the pathogenesis, good models to study, and effective therapeutic options. However, recent technological advances including somatic cell reprogramming to induced pluripotent stem cells (iPSCs), organoid technology, and tailored endonucleases provide unprecedented opportunities to fill these gaps, casting hope to soon cure the major primary mitochondrial phenotypes reviewed here. This group of rare diseases represents a key model for tackling the pathogenic mechanisms involving mitochondrial biology relevant to much more common disorders that affect our currently ageing population, such as diabetes and metabolic syndrome, neurodegenerative and inflammatory disorders, and cancer.
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3
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McKay SE, Yan W, Nouws J, Thormann MJ, Raimundo N, Khan A, Santos-Sacchi J, Song L, Shadel GS. Auditory Pathology in a Transgenic mtTFB1 Mouse Model of Mitochondrial Deafness. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:3132-40. [PMID: 26552864 DOI: 10.1016/j.ajpath.2015.08.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 07/31/2015] [Accepted: 08/14/2015] [Indexed: 12/13/2022]
Abstract
The A1555G mutation in the 12S rRNA gene of human mitochondrial DNA causes maternally inherited, nonsyndromic deafness, an extreme case of tissue-specific mitochondrial pathology. A transgenic mouse strain that robustly overexpresses the mitochondrial 12S ribosomal RNA methyltransferase TFB1M (Tg-mtTFB1 mice) exhibits progressive hearing loss that we proposed models aspects of A1555G-related pathology in humans. Although our previous studies of Tg-mtTFB1 mice implicated apoptosis in the spiral ganglion and stria vascularis because of mitochondrial reactive oxygen species-mediated activation of AMP kinase (AMPK) and the nuclear transcription factor E2F1, detailed auditory pathology was not delineated. Herein, we show that Tg-mtTFB1 mice have reduced endocochlear potential, indicative of significant stria vascularis dysfunction, but without obvious signs of strial atrophy. We also observed decreased auditory brainstem response peak 1 amplitude and prolonged wave I latency, consistent with apoptosis of spiral ganglion neurons. Although no major loss of hair cells was observed, there was a mild impairment of voltage-dependent electromotility of outer hair cells. On the basis of these results, we propose that these events conspire to produce the progressive hearing loss phenotype in Tg-mtTFB1 mice. Finally, genetically reducing AMPK α1 rescues hearing loss in Tg-mtTFB1 mice, confirming that aberrant up-regulation of AMPK signaling promotes the observed auditory pathology. The relevance of these findings to human A1555G patients and the potential therapeutic value of reducing AMPK activity are discussed.
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Affiliation(s)
- Sharen E McKay
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut; Department of Psychology, University of Bridgeport, Bridgeport, Connecticut
| | - Wayne Yan
- Department of Surgery, Yale School of Medicine, New Haven, Connecticut
| | - Jessica Nouws
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | | | - Nuno Raimundo
- Institute of Cell Biology, University Medical Center Göettingen, Göttingen, Germany
| | - Abdul Khan
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Joseph Santos-Sacchi
- Department of Surgery, Yale School of Medicine, New Haven, Connecticut; Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut; Department of Neurobiology, Yale School of Medicine, New Haven, Connecticut.
| | - Lei Song
- Department of Surgery, Yale School of Medicine, New Haven, Connecticut.
| | - Gerald S Shadel
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut; Department of Genetics, Yale School of Medicine, New Haven, Connecticut.
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4
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Abstract
PURPOSE OF REVIEW With the proliferation of assisted reproductive technologies, there is an increasing awareness of the importance of sperm DNA damage. With the recent advent of in-vitro fertilization/intracytoplasmic sperm injection, we are bypassing the normal natural selection barriers and potentially introducing sperm with damaged DNA. To date, these consequences are still largely unknown. RECENT FINDINGS Infertile men possess substantially more DNA-damaged sperm than fertile men, and this DNA damage may adversely affect reproductive outcomes. There may be a threshold level of DNA damage beyond which embryo development and subsequent pregnancy are impaired. Protamine deficiency and the effect of reactive oxygen species have been implicated in the etiology of sperm DNA damage. Assays of DNA damage are being used clinically to quantify objectively the degree of DNA damage in the sperm of infertile men in the hope of identifying more accurate ways of gauging fertility potential. SUMMARY There now exists clinical evidence to show that sperm DNA damage is detrimental to reproductive outcomes. Tests for DNA damage may provide better prognostic information and may allow for better decision-making than standard semen parameters when evaluating the infertile couple. The etiology of the DNA damage and the full extent of the damage on reproductive outcomes need further study.
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Affiliation(s)
- Armand Zini
- Division of Urology, Department of Surgery, McGill University, and St. Mary's Hospital, 3830 Lacombe Avenue, Montreal, Quebec, Canada.
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5
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O'Brien J, Zini A. Sperm DNA integrity and male infertility. Urology 2005; 65:16-22. [PMID: 15667855 DOI: 10.1016/j.urology.2004.07.015] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Accepted: 07/13/2004] [Indexed: 11/15/2022]
Affiliation(s)
- Jeanne O'Brien
- Division of Urology, Department of Surgery, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
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Wang S, Bian Q, Liu Z, Feng Y, Lian N, Chen H, Hu C, Dong Y, Cai Z. Capability of serum to convert streptomycin to cytotoxin in patients with aminoglycoside-induced hearing loss. Hear Res 1999; 137:1-7. [PMID: 10545628 DOI: 10.1016/s0378-5955(99)00116-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Individual variations in sensitivity to the ototoxic effects of aminoglycoside antibiotics are well documented. Our research demonstrates that there is an apparent difference in serum from patients who are resistant or susceptible to aminoglycoside ototoxicity. In the first study, the cytotoxicity of sera from patients with and without hearing loss after various time periods following the discontinuation of aminoglycoside treatment was assayed using the isolated outer hair cell toxicity assay. The results indicate that sera from patients with hearing loss were significantly more toxic than sera from patients with normal hearing or minimal hearing loss. This toxicity may persist for up to 1 year after discontinuation of aminoglycoside therapy. In a second study, sera were obtained from patients who had received aminoglycoside therapy several years previously. None of these sera was toxic to isolated outer hair cells in vitro. Streptomycin was then incubated with the sera or a protein fraction isolated from sera, and the incubation mixtures were tested for toxicity. The percentage of damaged outer hair cells was significantly higher when streptomycin had been treated with sera or a serum protein fraction from patients with hearing loss (58+/-10% and 68+/-9%, respectively) than with sera or a serum protein fraction from a control group (10+/-5% and 17+/-4%, respectively). In addition, several incubation mixtures were analyzed using high performance liquid chromatography. A new chromatographic peak was only found in the incubations of streptomycin with serum protein from patients with hearing loss. The results suggest that sera from individuals sensitive to aminoglycoside antibiotics may metabolize these drugs to cytotoxins.
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Affiliation(s)
- S Wang
- Beijing Institute of Otorhinolaryngology, 17# Hougou Lane Chong-Nei, Beijing, PR China
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7
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Abstract
The present study investigated the ability of gentamicin to catalyze free radical reactions and probed the underlying mechanisms by hydroethidine imaging, oxygen consumption, and reduction of cytochrome c. In Epstein-Barr virus-transformed lymphoblastoid cells, a respiratory burst was induced by phorbol ester and detected by hydroethidine, a fluorescent indicator of superoxide radical. The addition of gentamicin increased the fluorescence two-fold while gentamicin did not produce fluorescence in the absence of phorbol ester. In membrane preparations, gentamicin did not enhance NADPH consumption ruling out a direct activation of NADPH oxidase. The formation of reactive oxygen species by gentamicin was additionally supported by experiments that showed gentamicin increased oxygen consumption two-fold in intact cells and a cell-free system. In addition, generation of superoxide was indicated by the gentamicin-stimulated reduction of cytochrome c. The stimulation by gentamicin depended upon the presence of iron (FeII/FeIII) and of arachidonic acid as an electron donor. These results support the hypothesis that an iron-gentamicin complex can increase reactive oxygen species in nonenzymatic and in biological systems. The requirement for a reductive activation in intact cells (e.g., by a respiratory burst) is interpreted as the conversion of an inactive FeIII-gentamicin to a redox-active FeII-gentamicin complex.
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Affiliation(s)
- S H Sha
- Kresge Hearing Research Institute, Department of Otolaryngology, University of Michigan, Ann Arbor 48109-0506, USA
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8
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Abstract
We have previously shown gentamicin to form a redox-active iron chelate. This study investigates whether other aminoglycosides can likewise stimulate the generation of reactive oxygen species (free radicals). Kanamycin, neomycin and streptomycin were compared to gentamicin in intact cells and in cell-free in vitro assays using luminescence detection with lucigenin or luminol. Neutrophils and Epstein-Barr virus-transformed lymphoblastoid cells served as cell models in which a respiratory burst of superoxide was induced by phorbol ester. The addition of millimolar amounts of any of the aminoglycosides increased the luminescence significantly. The drugs also increased the formation of free radicals in an enzymatic (hypoxanthine-xanthine oxidase) and a non-enzymatic (phenazine methosulfate-NADH) superoxide-generating system. Half-maximal stimulation was reached with (0.4 mM gentamicin, and there was an absolute requirement for an electron donor, arachidonic acid. In both intact cells and cell-free systems, gentamicin-enhanced luminosity was suppressed by iron chelators. These results demonstrate that different aminoglycoside antibiotics can stimulate the formation of free radicals in biological and in cell-free systems. Luminescence detection is a convenient assay method to investigate the redox properties of these drugs.
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Affiliation(s)
- S H Sha
- Kresge Hearing Research Institute, Department of Otolaryngology, University of Michigan, Ann Arbor 48109-0506, USA
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Wackym PA, Kerner MM, Grody WW. Molecular temporal bone pathology: IV. Analysis of DNA template length using mitochondrial PCR primers. Laryngoscope 1998; 108:4-7. [PMID: 9707260 DOI: 10.1097/00005537-199808001-00002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The focus of this study was to identify, via molecular biology techniques, the length of the DNA templates present in individual archival celloidin-embedded human temporal bone sections. Earlier studies have suggested that the maximum template length present in these tissues is on the order of 471 base pair (bp). Polymerase chain reaction (PCR) amplification of 92 bp, 121 bp, 471 bp, and 609 bp regions of mitochondrial DNA (mtDNA), extracted from single archival celloidin-embedded human temporal bone sections, was used to assess the length of the template DNA extracted. These data are crucial to determine the limits of applying PCR technology to amplify specific genomic DNA targets located within the human inner ear. The results described should be of value to those investigators extracting DNA from archival individual human temporal bone sections for polymerase chain reaction assays of specific genetic alterations or infectious agents associated with temporal bone pathologies.
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Affiliation(s)
- P A Wackym
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee 53226, USA
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10
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Michikawa Y, Hofhaus G, Lerman LS, Attardi G. Comprehensive, rapid and sensitive detection of sequence variants of human mitochondrial tRNA genes. Nucleic Acids Res 1997; 25:2455-63. [PMID: 9171099 PMCID: PMC146751 DOI: 10.1093/nar/25.12.2455] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In the present study, a comprehensive, rapid and sensitive method for screening sequence variation of the human mitochondrial tRNA genes has been developed. For this purpose, the denaturing gradient gel electrophoresis (DGGE) technique has been appropriately modified for simultaneous mutation analysis of a large number of samples and adapted so as to circumvent the problems caused by the anomalous electrophoretic behavior of DNA fragments encoding tRNA genes. Eighteen segments of mitochondrial DNA (mtDNA), each containing a single uniform melting domain, were selected to cover all tRNA-encoding regions using the computer program MELT94. All 18 segments were simultaneously analyzed by electrophoresis through a single broad range denaturing gradient gel under rigorously defined conditions, which prevent band broadening and other migration abnormalities from interfering with detection of sequence variants. All base substitutions tested, which include six natural mutations and 14 artificially introduced ones, have been detected successfully in the present study. Several types of evidence strongly suggest that the anomalous behavior in DGGE of tRNA gene-containing mtDNA fragments reflects their tendency to form temporary or stable alternative secondary structures under semi-denaturing conditions. The high sensitivity of the method, which can detect as low as 10% of mutant mtDNA visually, makes it valuable for the analysis of heteroplasmic mutations.
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MESH Headings
- Cell Line
- DNA, Mitochondrial/genetics
- Genetic Variation
- Humans
- Nucleic Acid Heteroduplexes/biosynthesis
- Point Mutation
- RNA/biosynthesis
- RNA/genetics
- RNA, Mitochondrial
- RNA, Transfer, Amino Acid-Specific/biosynthesis
- RNA, Transfer, Amino Acid-Specific/genetics
- RNA, Transfer, Leu/biosynthesis
- RNA, Transfer, Leu/genetics
- RNA, Transfer, Lys/biosynthesis
- RNA, Transfer, Lys/genetics
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Affiliation(s)
- Y Michikawa
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
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11
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Priuska EM, Schacht J. Mechanism and Prevention of Aminoglycoside Ototoxicity: Outer Hair Cells as Targets and Tools. EAR, NOSE & THROAT JOURNAL 1997. [DOI: 10.1177/014556139707600310] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Eric M. Priuska
- Kresge Hearing Research Institute, University of Michigan, Ann Arbor, Michigan
| | - Jochen Schacht
- Kresge Hearing Research Institute, University of Michigan, Ann Arbor, Michigan
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12
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Abstract
Hearing loss is the most frequent sensory defect in humans. Dozens of genes may be responsible for the early onset forms of isolated deafness and several hundreds of syndromes with hearing loss have been described. Both the difficulties encountered by linkage analysis in families affected by isolated deafness and the paucity of data concerning the molecular components specifically involved in the peripheral auditory process, have long hampered the identification of genes responsible for hereditary hearing loss. Rapid progress is now being made in both fields. This should allow completion of major pieces of the jigsaw for understanding the development and function of the ear.
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Affiliation(s)
- C Petit
- Unité de Génétique Moléculaire Humaine, URA 1968, CNRS, Institut Pasteur, Paris, France.
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13
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Weber WW. Influence of heredity on human sensitivity to environmental chemicals. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1995; 25 Suppl 26:102-114. [PMID: 7789356 DOI: 10.1002/em.2850250614] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Hereditary peculiarities in individual responses to environmental chemicals are a common occurrence in human populations. Genetic variation in glutathione S-transferase, CYP1A2, N-acetyltransferase, and paraoxonase exemplify the relationship of metabolic variation to individual susceptibility to cancer and other toxicants of environmental origin. Heritable receptor protein variants, a subset of proteins of enormous pharmacogenetic potential that have not thus far been extensively explored from the pharmacogenetic standpoint, are also considered. Examples of interest that are considered include receptor variants associated with retinoic acid resistance in acute promyelocytic leukemia, with paradoxical responses to antiandrogens in prostate cancer, and with retinitis pigmentosa. Additional heritable protein variants of pharmacogenetic interest that result in antibiotic-induced deafness, glucocorticoid-remediable aldosteronism and hypertension, the long-QT syndrome, and beryllium-induced lung disease are also discussed. These traits demonstrate how knowledge of the molecular basis and mechanism of the variant response may contribute to its prevention in sensitive persons as well as to improved therapy for genetically conditioned disorders that arise from environmental chemicals.
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Affiliation(s)
- W W Weber
- Department of Pharmacology, University of Michigan, Ann Arbor 48109-0632, USA
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14
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Abstract
Mitochondrial ATP production via oxidative phosphorylation (OXPHOS) is essential for normal function and maintenance of human organ systems. Since OXPHOS biogenesis depends on both nuclear- and mitochondrial-encoded gene products, mutations in both genomes can result in impaired electron transport and ATP synthesis, thus causing tissue dysfunction and, ultimately, human disease. Over 30 mitochondrial DNA (mtDNA) point mutations and over 100 mtDNA rearrangements have now been identified as etiological factors in human disease. Because of the unique characteristics of mtDNA genetics, genotype/phenotype associations are often complex and disease expression can be influenced by a number of factors, including the presence of nuclear modifying or susceptibility alleles. Accordingly, these mutations result in an extraordinarily broad spectrum of clinical phenotypes ranging from systemic, lethal pediatric disease to late-onset, tissue-specific neurodegenerative disorders. In spite of its complexity, an understanding of the molecular basis of mitochondrial DNA disease will be essential as the first step toward rationale and permanent curative therapy.
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Affiliation(s)
- M D Brown
- Department of Genetics and Molecular Medicine, Atlanta, Georgia 30333
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15
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Reid FM, Vernham GA, Jacobs HT. A novel mitochondrial point mutation in a maternal pedigree with sensorineural deafness. Hum Mutat 1994; 3:243-7. [PMID: 8019558 DOI: 10.1002/humu.1380030311] [Citation(s) in RCA: 169] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We have detected a novel mitochondrial mutation in a maternal pedigree, at least 13 of whose members have sensorineural hearing loss of varying severity, but who exhibit no other pathological features. The mutation, at np 7445, converts the 3' terminal T residue of tRNA-ser(UCN) to a C, and also brings about a silent alteration to the COI stop codon. The mutation destroys an XbaI site, within which a second mutation, at np 7444, has previously been reported in association with Leber's hereditary optic neuropathy. Predominantly mutant mtDNA was found in all 13 family members surveyed, whether or not they are overtly affected by deafness, and some individuals appeared homoplasmic, within the limits of detection. The novel mutation was not found in over 600 normal controls, nor in any of 27 other maternally unrelated individuals with deafness Other mutations found in mitochondrial disorders were also absent from this pedigree.
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Affiliation(s)
- F M Reid
- Robertson Institute of Biotechnology, Department of Genetics, University of Glasgow, Scotland, UK
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16
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Fischel-Ghodsian N, Prezant TR, Bu X, Oztas S. Mitochondrial ribosomal RNA gene mutation in a patient with sporadic aminoglycoside ototoxicity. Am J Otolaryngol 1993; 14:399-403. [PMID: 8285309 DOI: 10.1016/0196-0709(93)90113-l] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE Aminoglycoside-induced deafness has been described in a number of Chinese pedigrees. In nearly all of these families, affected individuals were related through the maternal side. Because mitochondrial DNA is transmitted exclusively through mothers, it had been speculated that a mutation in the mitochondrial DNA might predispose these maternally related family members to aminoglycoside ototoxicity. Recently, we analyzed three such families with multiple cases of ototoxic deafness and identified a pathogenic mutation in the mitochondrial 12S ribosomal RNA gene at nucleotide position 1555. The purpose of the current study is to analyze individuals with no family history of deafness, who had severe hearing loss after aminoglycoside exposure, for presence or absence of this particular mitochondrial DNA mutation. MATERIALS AND METHODS Blood was obtained from 36 Chinese individuals who became deaf after aminoglycoside exposure and had no family history of deafness. The DNA of these individuals was extracted, amplified by the polymerase chain reaction, and analyzed for the mitochondrial ribosomal RNA gene mutation by allele-specific oligonucleotide hybridization and Southern blot analysis. RESULTS In one of these 36 sporadic cases, we identified the nucleotide 1555 A-->G mutation in the mitochondrial genome. CONCLUSION This finding implies that a small proportion of individuals at risk for aminoglycoside ototoxicity harbor the specific mitochondrial DNA mutation identified in the familial cases. In these individuals, a genetic susceptibility to the ototoxic effects of aminoglycosides can be diagnosed, and deafness can be prevented in maternal relatives by avoiding the use of these antibiotics.
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Affiliation(s)
- N Fischel-Ghodsian
- Ahmanson Department of Pediatrics, Steven Spielberg Pediatric Research Center, Los Angeles, CA
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17
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Abstract
Mitochondrial DNA mutations cause several human diseases, (eg, Leber's hereditary optic neuropathy). Wolfram syndrome (characterised by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness) also has, in some cases, a mitochondrial origin. The disease, often familial, has been well documented as an autosomal recessive disorder, and most of the clinical phenotypes are consistent with an ATP supply defect that is often seen in mitochondrial-mediated disorders. We propose a dual genome defect model for Wolfram syndrome in which nuclear genetic defects or mitochondrial genetic defects can independently lead to the disease. This model suggests that besides a mitochondrial gene defect alone, a nuclear gene defect, which interferes with the normal function of mitochondria (probably with a normal mitochondrial genome), can also be the underlying explanation for the pleiotropic features of Wolfram syndrome. This hypothesis explains how an autosomal recessive disorder can result in mitochondrial dysfunction, and has a general application in the identification of candidate genes for the various important phenotypes (eg, deafness and diabetes mellitus) seen in mitochondrial disorders.
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Affiliation(s)
- X Bu
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California 90048
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18
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Prezant TR, Agapian JV, Bohlman MC, Bu X, Oztas S, Qiu WQ, Arnos KS, Cortopassi GA, Jaber L, Rotter JI. Mitochondrial ribosomal RNA mutation associated with both antibiotic-induced and non-syndromic deafness. Nat Genet 1993; 4:289-94. [PMID: 7689389 DOI: 10.1038/ng0793-289] [Citation(s) in RCA: 792] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Maternally transmitted non-syndromic deafness was described recently both in pedigrees with susceptibility to aminoglycoside ototoxicity and in a large Arab-Israeli pedigree. Because of the known action of aminoglycosides on bacterial ribosomes, we analysed the sequence of the mitochondrial rRNA genes of three unrelated patients with familial aminoglycoside-induced deafness. We also sequenced the complete mitochondrial genome of the Arab-Israeli pedigree. All four families shared a nucleotide 1555 A to G substitution in the 12S rRNA gene, a site implicated in aminoglycoside activity. Our study offers the first description of a mitochondrial rRNA mutation leading to disease, the first cases of non-syndromic deafness caused by a mitochondrial DNA mutation and the first molecular genetic study of antibiotic-induced ototoxicity.
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Affiliation(s)
- T R Prezant
- Ahmanson Department of Pediatrics Steven Spielberg Pediatric Research Center, Cedars-Sinai Medical Center, Los Angeles, California
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19
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Bu X, Shohat M, Jaber L, Rotter JI. A form of sensorineural deafness is determined by a mitochondrial and an autosomal locus: evidence from pedigree segregation analysis. Genet Epidemiol 1993; 10:3-15. [PMID: 8472932 DOI: 10.1002/gepi.1370100102] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have previously reported a large Israeli-Arab pedigree with sensorineural deafness possibly determined simultaneously by two loci--one mitochondrial, and one autosomal recessive. This was analyzed by extending classic segregation analysis methods to the many nuclear families derived from the maternal line pedigree. Here we expand this pedigree and extend our analysis by using the regressive models for segregation analysis on the entire pedigree. The corresponding REGD computer program was utilized and the marrying-in males' and paternal line members' affection statuses were assigned as unknown to accommodate the exclusive maternal transmission pattern. For the autosomal locus, a simple autosomal recessive (q = 0.52) model with a nearly complete penetrance (0.93) was found to be the best-fitting model. Equally importantly, we were also able to use the power of the regressive models to test the hypothesis of mitochondrial heteroplasmy as an alternative for the proposed autosomal locus. We found no evidence for the heteroplasmy hypothesis as an explanation for the incomplete maternal transmission of deafness in this pedigree. Thus, even if the mitochondrial mutation occurred in a heteroplasmic distribution in the family members, this could not explain the familial aggregation in this pedigree, and an autosomal recessive locus is still required. These results provide further support for the concept that the sensorineural deafness occurring in this large Israeli-Arab pedigree results from simultaneous involvement of two genes at two different loci, one mitochondrial and likely homoplasmic, and the other autosomal and recessive.
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Affiliation(s)
- X Bu
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048
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