1
|
Loguercio Polosa P, Capriglia F, Bruni F. Molecular Investigation of Mitochondrial RNA19 Role in the Pathogenesis of MELAS Disease. Life (Basel) 2023; 13:1863. [PMID: 37763267 PMCID: PMC10532844 DOI: 10.3390/life13091863] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/16/2023] [Accepted: 08/31/2023] [Indexed: 09/29/2023] Open
Abstract
In mammalian mitochondria, the processing of primary RNA transcripts involves a coordinated series of cleavage and modification events, leading to the formation of processing intermediates and mature mt-RNAs. RNA19 is an unusually stable unprocessed precursor, physiologically polyadenylated, which includes the 16S mt-rRNA, the mt-tRNALeuUUR and the mt-ND1 mRNA. These peculiarities, together with the alteration of its steady-state levels in cellular models with defects in mitochondrial function, make RNA19 a potentially important molecule for the physiological regulation of mitochondrial molecular processes as well as for the pathogenesis of mitochondrial diseases. In this work, we quantitatively and qualitatively examined RNA19 in MELAS trans-mitochondrial cybrids carrying the mtDNA 3243A>G transition and displaying a profound mitochondrial translation defect. Through a combination of isokinetic sucrose gradient and RT-qPCR experiments, we found that RNA19 accumulated and co-sedimented with the mitoribosomal large subunit (mt-LSU) in mutant cells. Intriguingly, exogenous expression of the isolated LARS2 C-terminal domain (Cterm), which was shown to rescue defective translation in MELAS cybrids, decreased the levels of mt-LSU-associated RNA19 by relegating it to the pool of free unbound RNAs. Overall, the data reported here support a regulatory role for RNA19 in mitochondrial physiopathological processes, designating this RNA precursor as a possible molecular target in view of therapeutic strategy development.
Collapse
Affiliation(s)
| | | | - Francesco Bruni
- Department of Biosciences, Biotechnologies and Environment, University of Bari ‘Aldo Moro’, 70125 Bari, Italy; (P.L.P.); (F.C.)
| |
Collapse
|
2
|
Tomoda E, Nagao A, Shirai Y, Asano K, Suzuki T, Battersby B, Suzuki T. Restoration of mitochondrial function through activation of hypomodified tRNAs with pathogenic mutations associated with mitochondrial diseases. Nucleic Acids Res 2023; 51:7563-7579. [PMID: 36928678 PMCID: PMC10415153 DOI: 10.1093/nar/gkad139] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 02/14/2023] [Accepted: 03/08/2023] [Indexed: 03/18/2023] Open
Abstract
Mutations in mitochondrial (mt-)tRNAs frequently cause mitochondrial dysfunction. Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), and myoclonus epilepsy associated with ragged red fibers (MERRF) are major clinical subgroups of mitochondrial diseases caused by pathogenic point mutations in tRNA genes encoded in mtDNA. We previously reported a severe reduction in the frequency of 5-taurinomethyluridine (τm5U) and its 2-thiouridine derivative (τm5s2U) in the anticodons of mutant mt-tRNAs isolated from the cells of patients with MELAS and MERRF, respectively. The hypomodified tRNAs fail to decode cognate codons efficiently, resulting in defective translation of respiratory chain proteins in mitochondria. To restore the mitochondrial activity of MELAS patient cells, we overexpressed MTO1, a τm5U-modifying enzyme, in patient-derived myoblasts. We used a newly developed primer extension method and showed that MTO1 overexpression almost completely restored the τm5U modification of the MELAS mutant mt-tRNALeu(UUR). An increase in mitochondrial protein synthesis and oxygen consumption rate suggested that the mitochondrial function of MELAS patient cells can be activated by restoring the τm5U of the mutant tRNA. In addition, we confirmed that MTO1 expression restored the τm5s2U of the mutant mt-tRNALys in MERRF patient cells. These findings pave the way for epitranscriptomic therapies for mitochondrial diseases.
Collapse
Affiliation(s)
- Ena Tomoda
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Asuteka Nagao
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yuki Shirai
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kana Asano
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeo Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | | | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
3
|
Yu T, Zhang Y, Zheng WQ, Wu S, Li G, Zhang Y, Li N, Yao R, Fang P, Wang J, Zhou XL. Selective degradation of tRNASer(AGY) is the primary driver for mitochondrial seryl-tRNA synthetase-related disease. Nucleic Acids Res 2022; 50:11755-11774. [PMID: 36350636 PMCID: PMC9723649 DOI: 10.1093/nar/gkac1028] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/13/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022] Open
Abstract
Mitochondrial translation is of high significance for cellular energy homeostasis. Aminoacyl-tRNA synthetases (aaRSs) are crucial translational components. Mitochondrial aaRS variants cause various human diseases. However, the pathogenesis of the vast majority of these diseases remains unknown. Here, we identified two novel SARS2 (encoding mitochondrial seryl-tRNA synthetase) variants that cause a multisystem disorder. c.654-14T > A mutation induced mRNA mis-splicing, generating a peptide insertion in the active site; c.1519dupC swapped a critical tRNA-binding motif in the C-terminus due to stop codon readthrough. Both mutants exhibited severely diminished tRNA binding and aminoacylation capacities. A marked reduction in mitochondrial tRNASer(AGY) was observed due to RNA degradation in patient-derived induced pluripotent stem cells (iPSCs), causing impaired translation and comprehensive mitochondrial function deficiencies. These impairments were efficiently rescued by wild-type SARS2 overexpression. Either mutation caused early embryonic fatality in mice. Heterozygous mice displayed reduced muscle tissue-specific levels of tRNASers. Our findings elucidated the biochemical and cellular consequences of impaired translation mediated by SARS2, suggesting that reduced abundance of tRNASer(AGY) is a key determinant for development of SARS2-related diseases.
Collapse
Affiliation(s)
| | | | - Wen-Qiang Zheng
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Siqi Wu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Guoqiang Li
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Key Laboratory of Clinical Molecular Diagnostics for Pediatrics, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, 1678 Dong Fang Road, Shanghai 200127, China
| | - Yong Zhang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Niu Li
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Key Laboratory of Clinical Molecular Diagnostics for Pediatrics, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, 1678 Dong Fang Road, Shanghai 200127, China
| | - Ruen Yao
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Key Laboratory of Clinical Molecular Diagnostics for Pediatrics, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, 1678 Dong Fang Road, Shanghai 200127, China
| | - Pengfei Fang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Jian Wang
- Correspondence may also be addressed to Jian Wang. Tel: +86 21 3808 7371;
| | - Xiao-Long Zhou
- To whom correspondence should be addressed. Tel: +86 21 5492 1247; Fax: +86 21 5492 1011;
| |
Collapse
|
4
|
Exploring the Ability of LARS2 Carboxy-Terminal Domain in Rescuing the MELAS Phenotype. Life (Basel) 2021; 11:life11070674. [PMID: 34357047 PMCID: PMC8303833 DOI: 10.3390/life11070674] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 12/25/2022] Open
Abstract
The m.3243A>G mutation within the mitochondrial mt-tRNALeu(UUR) gene is the most prevalent variant linked to mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome. This pathogenic mutation causes severe impairment of mitochondrial protein synthesis due to alterations of the mutated tRNA, such as reduced aminoacylation and a lack of post-transcriptional modification. In transmitochondrial cybrids, overexpression of human mitochondrial leucyl-tRNA synthetase (LARS2) has proven effective in rescuing the phenotype associated with m.3243A>G substitution. The rescuing activity resides in the carboxy-terminal domain (Cterm) of the enzyme; however, the precise molecular mechanisms underlying this process have not been fully elucidated. To deepen our knowledge on the rescuing mechanisms, we demonstrated the interactions of the Cterm with mutated mt-tRNALeu(UUR) and its precursor in MELAS cybrids. Further, the effect of Cterm expression on mitochondrial functions was evaluated. We found that Cterm ameliorates de novo mitochondrial protein synthesis, whilst it has no effect on mt-tRNALeu(UUR) steady-state levels and aminoacylation. Despite the complete recovery of cell viability and the increase in mitochondrial translation, Cterm-overexpressing cybrids were not able to recover bioenergetic competence. These data suggest that, in our MELAS cell model, the beneficial effect of Cterm may be mediated by factors that are independent of the mitochondrial bioenergetics.
Collapse
|
5
|
Richter U, McFarland R, Taylor RW, Pickett SJ. The molecular pathology of pathogenic mitochondrial tRNA variants. FEBS Lett 2021; 595:1003-1024. [PMID: 33513266 PMCID: PMC8600956 DOI: 10.1002/1873-3468.14049] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/14/2021] [Accepted: 01/18/2021] [Indexed: 12/16/2022]
Abstract
Mitochondrial diseases are clinically and genetically heterogeneous disorders, caused by pathogenic variants in either the nuclear or mitochondrial genome. This heterogeneity is particularly striking for disease caused by variants in mitochondrial DNA‐encoded tRNA (mt‐tRNA) genes, posing challenges for both the treatment of patients and understanding the molecular pathology. In this review, we consider disease caused by the two most common pathogenic mt‐tRNA variants: m.3243A>G (within MT‐TL1, encoding mt‐tRNALeu(UUR)) and m.8344A>G (within MT‐TK, encoding mt‐tRNALys), which together account for the vast majority of all mt‐tRNA‐related disease. We compare and contrast the clinical disease they are associated with, as well as their molecular pathologies, and consider what is known about the likely molecular mechanisms of disease. Finally, we discuss the role of mitochondrial–nuclear crosstalk in the manifestation of mt‐tRNA‐associated disease and how research in this area not only has the potential to uncover molecular mechanisms responsible for the vast clinical heterogeneity associated with these variants but also pave the way to develop treatment options for these devastating diseases.
Collapse
Affiliation(s)
- Uwe Richter
- Wellcome Centre for Mitochondrial Research, The Medical School, Newcastle University, UK.,Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Finland.,Newcastle University Biosciences Institute, Newcastle University, UK
| | - Robert McFarland
- Wellcome Centre for Mitochondrial Research, The Medical School, Newcastle University, UK.,Newcastle University Translational and Clinical Research Institute, Newcastle University, UK
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, The Medical School, Newcastle University, UK.,Newcastle University Translational and Clinical Research Institute, Newcastle University, UK
| | - Sarah J Pickett
- Wellcome Centre for Mitochondrial Research, The Medical School, Newcastle University, UK.,Newcastle University Translational and Clinical Research Institute, Newcastle University, UK
| |
Collapse
|
6
|
Perli E, Pisano A, Pignataro MG, Campese AF, Pelullo M, Genovese I, de Turris V, Ghelli AM, Cerbelli B, Giordano C, Colotti G, Morea V, d'Amati G. Exogenous peptides are able to penetrate human cell and mitochondrial membranes, stabilize mitochondrial tRNA structures, and rescue severe mitochondrial defects. FASEB J 2020; 34:7675-7686. [PMID: 32304340 DOI: 10.1096/fj.201903270r] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 03/04/2020] [Accepted: 03/24/2020] [Indexed: 12/14/2022]
Abstract
Mutations in mitochondrial transfer RNA (mt-tRNA) genes are responsible for a wide range of syndromes, for which no effective treatment is available. We previously reported that transfection of the nucleotide sequence encoding for the 16-residue β32_33 peptide from mitochondrial leucyl-tRNA synthetase ameliorates the cell phenotype caused by the mitochondrial tRNA mutations. In this work, we demonstrated that both the β32_33 peptide linked with the known (L)-Phe-(D)-Arg-(L)-Phe-(L)-Lys (FrFK) mitochondrial penetrating sequence and, strikingly, the β32_33 peptide per se, are able to penetrate both the plasma and mitochondrial membranes and exert the rescuing activity when exogenously administered to cells bearing the mutations m.3243A > G and m.8344A > G. These mutations are responsible for the most common and severe mt-tRNA-related diseases. In addition, we dissected the molecular determinants of constructs activity by showing that both the order of amino acids along the sequence and presence of positive charges are essential determinants of the peptide activity in cells and mt-tRNA structures stabilization in vitro. In view of future in vivo studies, this information may be required to design of β32_33 peptide-mimetic derivatives. The β32_33 and FrFK-β32_33 peptides are, therefore, promising molecules for the development of therapeutic agents against diseases caused by the mt-tRNA point mutations.
Collapse
Affiliation(s)
- Elena Perli
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - Annalinda Pisano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - Maria Gemma Pignataro
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | | | - Maria Pelullo
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Ilaria Genovese
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Rome, Italy
| | - Valeria de Turris
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Anna Maria Ghelli
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, Bologna, Italy
| | - Bruna Cerbelli
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University, Latina, Italy
| | - Carla Giordano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - Gianni Colotti
- Institute of Molecular Biology and Pathology, National Research Council of Italy, Rome, Italy
| | - Veronica Morea
- Institute of Molecular Biology and Pathology, National Research Council of Italy, Rome, Italy
| | - Giulia d'Amati
- Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| |
Collapse
|
7
|
Gong S, Wang X, Meng F, Cui L, Yi Q, Zhao Q, Cang X, Cai Z, Mo JQ, Liang Y, Guan MX. Overexpression of mitochondrial histidyl-tRNA synthetase restores mitochondrial dysfunction caused by a deafness-associated tRNAHis mutation. J Biol Chem 2020. [DOI: 10.1016/s0021-9258(17)49906-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
8
|
Mitochondrial aminoacyl-tRNA synthetases. Enzymes 2020. [PMID: 33837704 DOI: 10.1016/bs.enz.2020.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2023]
Abstract
In all eukaryotic cells, protein synthesis occurs not only in the cytosol, but also in the mitochondria. Translation of mitochondrial genes requires a set of aminoacyl-tRNA synthetases, many of which are often specialized for organellar function. These enzymes have evolved unique mechanisms for tRNA recognition and for ensuring fidelity of translation. Mutations of human mitochondrial synthetases are associated with a wide range of pathogenic phenotypes, both highlighting the importance of their role in maintaining the cellular "powerhouse" and suggesting additional cellular roles.
Collapse
|
9
|
Gong S, Wang X, Meng F, Cui L, Yi Q, Zhao Q, Cang X, Cai Z, Mo JQ, Liang Y, Guan MX. Overexpression of mitochondrial histidyl-tRNA synthetase restores mitochondrial dysfunction caused by a deafness-associated tRNA His mutation. J Biol Chem 2019; 295:940-954. [PMID: 31819004 DOI: 10.1074/jbc.ra119.010998] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/27/2019] [Indexed: 01/19/2023] Open
Abstract
The deafness-associated m.12201T>C mutation affects the A5-U68 base-pairing within the acceptor stem of mitochondrial tRNAHis The primary defect in this mutation is an alteration in tRNAHis aminoacylation. Here, we further investigate the molecular mechanism of the deafness-associated tRNAHis 12201T>C mutation and test whether the overexpression of the human mitochondrial histidyl-tRNA synthetase gene (HARS2) in cytoplasmic hybrid (cybrid) cells carrying the m.12201T>C mutation reverses mitochondrial dysfunctions. Using molecular dynamics simulations, we demonstrate that the m.12201T>C mutation perturbs the tRNAHis structure and function, supported by decreased melting temperature, conformational changes, and instability of mutated tRNA. We show that the m.12201T>C mutation-induced alteration of aminoacylation tRNAHis causes mitochondrial translational defects and respiratory deficiency. We found that the transfer of HARS2 into the cybrids carrying the m.12201T>C mutation raises the levels of aminoacylated tRNAHis from 56.3 to 75.0% but does not change the aminoacylation of other tRNAs. Strikingly, HARS2 overexpression increased the steady-state levels of tRNAHis and of noncognate tRNAs, including tRNAAla, tRNAGln, tRNAGlu, tRNALeu(UUR), tRNALys, and tRNAMet, in cells bearing the m.12201T>C mutation. This improved tRNA metabolism elevated the efficiency of mitochondrial translation, activities of oxidative phosphorylation complexes, and respiration capacity. Furthermore, HARS2 overexpression markedly increased mitochondrial ATP levels and membrane potential and reduced production of reactive oxygen species in cells carrying the m.12201T>C mutation. These results indicate that HARS2 overexpression corrects the mitochondrial dysfunction caused by the tRNAHis mutation. These findings provide critical insights into the pathophysiology of mitochondrial disease and represent a step toward improved therapeutic interventions for mitochondrial disorders.
Collapse
Affiliation(s)
- Shasha Gong
- Taizhou University Hospital, Taizhou University, Taizhou, Zhejiang 318000, China.,Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaoqiong Wang
- Department of Otolaryngology, Taizhou Municipal Hospital, Taizhou, Zhejiang 318000, China.,Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Feilong Meng
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China.,Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Limei Cui
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Qiuzi Yi
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Qiong Zhao
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaohui Cang
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Zhiyi Cai
- Department of Otolaryngology, Taizhou Municipal Hospital, Taizhou, Zhejiang 318000, China
| | - Jun Qin Mo
- Department of Pathology, Rady Children's Hospital, University of California School of Medicine, San Diego, California 92123
| | - Yong Liang
- Taizhou University Hospital, Taizhou University, Taizhou, Zhejiang 318000, China
| | - Min-Xin Guan
- Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310058, China .,Division of Medical Genetics and Genomics, the Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.,Key Laboratory of Reproductive Genetics, Ministry of Education of PRC, Zhejiang University, Hangzhou, Zhejiang 310058, China.,Joint Institute of Genetics and Genomic Medicine between Zhejiang University and University of Toronto, Hangzhou, Zhejiang 310058, China
| |
Collapse
|
10
|
Tiosano D, Mears JA, Buchner DA. Mitochondrial Dysfunction in Primary Ovarian Insufficiency. Endocrinology 2019; 160:2353-2366. [PMID: 31393557 PMCID: PMC6760336 DOI: 10.1210/en.2019-00441] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/01/2019] [Indexed: 12/14/2022]
Abstract
Primary ovarian insufficiency (POI) is defined by the loss or dysfunction of ovarian follicles associated with amenorrhea before the age of 40. Symptoms include hot flashes, sleep disturbances, and depression, as well as reduced fertility and increased long-term risk of cardiovascular disease. POI occurs in ∼1% to 2% of women, although the etiology of most cases remains unexplained. Approximately 10% to 20% of POI cases are due to mutations in a single gene or a chromosomal abnormality, which has provided considerable molecular insight into the biological underpinnings of POI. Many of the genes for which mutations have been associated with POI, either isolated or syndromic cases, function within mitochondria, including MRPS22, POLG, TWNK, LARS2, HARS2, AARS2, CLPP, and LRPPRC. Collectively, these genes play roles in mitochondrial DNA replication, gene expression, and protein synthesis and degradation. Although mutations in these genes clearly implicate mitochondrial dysfunction in rare cases of POI, data are scant as to whether these genes in particular, and mitochondrial dysfunction in general, contribute to most POI cases that lack a known etiology. Further studies are needed to better elucidate the contribution of mitochondria to POI and determine whether there is a common molecular defect in mitochondrial function that distinguishes mitochondria-related genes that when mutated cause POI vs those that do not. Nonetheless, the clear implication of mitochondrial dysfunction in POI suggests that manipulation of mitochondrial function represents an important therapeutic target for the treatment or prevention of POI.
Collapse
Affiliation(s)
- Dov Tiosano
- Division of Pediatric Endocrinology, Ruth Rappaport Children’s Hospital, Rambam Medical Center, Haifa, Israel
- Rappaport Family Faculty of Medicine, Technion—Israel Institute of Technology, Haifa, Israel
- Correspondence: David A. Buchner, PhD, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106. E-mail: ; or Dov Tiosano, MD, Division of Pediatric Endocrinology, Ruth Rappaport Children’s Hospital, Rambam Medical Center, HaAliya HaShniya Street 8, Haifa 3109601, Israel. E-mail:
| | - Jason A Mears
- Center for Mitochondrial Diseases, Case Western Reserve University, Cleveland, Ohio
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - David A Buchner
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio
- Research Institute for Children’s Health, Case Western Reserve University, Cleveland, Ohio
- Correspondence: David A. Buchner, PhD, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106. E-mail: ; or Dov Tiosano, MD, Division of Pediatric Endocrinology, Ruth Rappaport Children’s Hospital, Rambam Medical Center, HaAliya HaShniya Street 8, Haifa 3109601, Israel. E-mail:
| |
Collapse
|
11
|
Asano K, Suzuki T, Saito A, Wei FY, Ikeuchi Y, Numata T, Tanaka R, Yamane Y, Yamamoto T, Goto T, Kishita Y, Murayama K, Ohtake A, Okazaki Y, Tomizawa K, Sakaguchi Y, Suzuki T. Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. Nucleic Acids Res 2019; 46:1565-1583. [PMID: 29390138 PMCID: PMC5829720 DOI: 10.1093/nar/gky068] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 01/23/2018] [Indexed: 12/21/2022] Open
Abstract
Modified uridine containing taurine, 5-taurinomethyluridine (τm5U), is found at the anticodon first position of mitochondrial (mt-)transfer RNAs (tRNAs). Previously, we reported that τm5U is absent in mt-tRNAs with pathogenic mutations associated with mitochondrial diseases. However, biogenesis and physiological role of τm5U remained elusive. Here, we elucidated τm5U biogenesis by confirming that 5,10-methylene-tetrahydrofolate and taurine are metabolic substrates for τm5U formation catalyzed by MTO1 and GTPBP3. GTPBP3-knockout cells exhibited respiratory defects and reduced mitochondrial translation. Very little τm5U34 was detected in patient's cells with the GTPBP3 mutation, demonstrating that lack of τm5U results in pathological consequences. Taurine starvation resulted in downregulation of τm5U frequency in cultured cells and animal tissues (cat liver and flatfish). Strikingly, 5-carboxymethylaminomethyluridine (cmnm5U), in which the taurine moiety of τm5U is replaced with glycine, was detected in mt-tRNAs from taurine-depleted cells. These results indicate that tRNA modifications are dynamically regulated via sensing of intracellular metabolites under physiological condition.
Collapse
Affiliation(s)
- Kana Asano
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeo Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Ayaka Saito
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Fan-Yan Wei
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Yoshiho Ikeuchi
- Institute of Industrial Science, University of Tokyo, Meguro-ku, Tokyo 153-8505, Japan
| | - Tomoyuki Numata
- Biological Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan
| | - Ryou Tanaka
- Department of Veterinary Surgery, Tokyo University of Agriculture and Technology, Animal Medical Center, Fuchu, Tokyo 183-8509, Japan
| | - Yoshihisa Yamane
- Department of Veterinary Surgery, Tokyo University of Agriculture and Technology, Animal Medical Center, Fuchu, Tokyo 183-8509, Japan
| | - Takeshi Yamamoto
- Tamaki Laboratory, National Research Institute of Aquaculture, Japan Fisheries Research and Education Agency, Tamaki, Mie 519-0423, Japan
| | - Takanobu Goto
- Department of Chemistry & Biochemistry, National Institute of Technology, Numazu College, Numazu, Shizuoka 410-8501, Japan
| | - Yoshihito Kishita
- Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University, Hidaka, Saitama 350-1240, Japan
| | - Kei Murayama
- Department of Metabolism, Chiba Children's Hospital, Midori-ku, Chiba 266-0007, Japan
| | - Akira Ohtake
- Department of Pediatrics, Saitama Medical University, Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan
| | - Yasushi Okazaki
- Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University, Hidaka, Saitama 350-1240, Japan.,Division of Translational Research, Research Center for Genomic Medicine, Saitama Medical University, Hidaka, Saitama 350-1240, Japan
| | - Kazuhito Tomizawa
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Yuriko Sakaguchi
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
12
|
Steiner RE, Ibba M. Regulation of tRNA-dependent translational quality control. IUBMB Life 2019; 71:1150-1157. [PMID: 31135095 DOI: 10.1002/iub.2080] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/01/2019] [Accepted: 05/14/2019] [Indexed: 02/06/2023]
Abstract
Translation is the most error-prone process in protein synthesis; however, it is important that accuracy is maintained because erroneous translation has been shown to affect all domains of life. Translational quality control is maintained by both proteins and RNA through intricate processes. The aminoacyl-tRNA synthetases help maintain high levels of translational accuracy through the esterification of tRNA and proofreading mechanisms. tRNA is often recognized by an aminoacyl-tRNA synthetase in a sequence and structurally dependent manner, sometimes involving modified nucleotides. Additionally, some proofreading mechanisms of aminoacyl-tRNA synthetases require tRNA elements for hydrolysis of a noncognate aminoacyl-tRNA. Finally, tRNA is also important for proper decoding of the mRNA message by codon and anticodon pairing. Here, recent developments regarding the importance of tRNA in maintenance of translational accuracy are reviewed. © 2019 IUBMB Life, 2019 © 2019 IUBMB Life, 71(8):1150-1157, 2019.
Collapse
Affiliation(s)
- Rebecca E Steiner
- The Ohio State University Biochemistry Program, The Ohio State University, Columbus, OH, USA.,Center for RNA Biology, The Ohio State University, Columbus, OH, USA
| | - Michael Ibba
- The Ohio State University Biochemistry Program, The Ohio State University, Columbus, OH, USA.,Center for RNA Biology, The Ohio State University, Columbus, OH, USA.,Department of Microbiology, The Ohio State University, Columbus, OH, USA
| |
Collapse
|
13
|
Zhao X, Han J, Zhu L, Xiao Y, Wang C, Hong F, Jiang P, Guan MX. Overexpression of human mitochondrial alanyl-tRNA synthetase suppresses biochemical defects of the mt-tRNA Ala mutation in cybrids. Int J Biol Sci 2018; 14:1437-1444. [PMID: 30262995 PMCID: PMC6158735 DOI: 10.7150/ijbs.27043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/17/2018] [Indexed: 11/13/2022] Open
Abstract
Mutations of mitochondrial transfer RNAs (mt-tRNAs) play a major role in a wide range of mitochondrial diseases because of the vital role of these molecules in mitochondrial translation. It has previously been reported that the overexpression of mitochondrial aminoacyl tRNA synthetases is effective at partially suppressing the defects resulting from mutations in their cognate mt-tRNAs in cells. Here we report a detailed analysis of the suppressive activities of mitochondrial alanyl-tRNA synthetase (AARS2) on mt-tRNAAla 5655 A>G mutant. Mitochondrial defects in respiration, activity of oxidative phosphorylation complexes, ATP production, mitochondrial superoxide, and membrane potential were consistently rescued in m.5655A>G cybrids upon AARS2 expression. However, AARS2 overexpression did not result in a detectable increase in mutated mt-tRNAAla but caused an increase incharged mt-tRNAAla in mutant cybrids, leading to enhanced mitochondrial translation. This indicated that AARS2 improved the aminoacylation activity in the case of m.5655A>G, rather than having a stabilizing effect on the tRNA structure. The data presented in this paper deepen our understanding of the pathogenesis of mt-tRNA diseases.
Collapse
Affiliation(s)
- Xiaoxu Zhao
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.,Institute of Genetics Zhejiang University, and Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Jiamin Han
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.,Institute of Genetics Zhejiang University, and Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Ling Zhu
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Yun Xiao
- Institute of Genetics Zhejiang University, and Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Chenghui Wang
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.,Institute of Genetics Zhejiang University, and Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Fang Hong
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Pingping Jiang
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.,Institute of Genetics Zhejiang University, and Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Min-Xin Guan
- Division of Medical Genetics and Genomics, The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.,Institute of Genetics Zhejiang University, and Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, 310058, China
| |
Collapse
|
14
|
Mitochondrial DNA transcription and translation: clinical syndromes. Essays Biochem 2018; 62:321-340. [PMID: 29980628 PMCID: PMC6056718 DOI: 10.1042/ebc20170103] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 05/17/2018] [Accepted: 05/21/2018] [Indexed: 01/15/2023]
Abstract
Diagnosing primary mitochondrial diseases is challenging in clinical practice. Although, defective oxidative phosphorylation (OXPHOS) is the common final pathway, it is unknown why different mtDNA or nuclear mutations result in largely heterogeneous and often tissue -specific clinical presentations. Mitochondrial tRNA (mt-tRNA) mutations are frequent causes of mitochondrial diseases both in children and adults. However numerous nuclear mutations involved in mitochondrial protein synthesis affecting ubiquitously expressed genes have been reported in association with very tissue specific clinical manifestations suggesting that there are so far unknown factors determining the tissue specificity in mitochondrial translation. Most of these gene defects result in histological abnormalities and multiple respiratory chain defects in the affected organs. The clinical phenotypes are usually early-onset, severe, and often fatal, implying the importance of mitochondrial translation from birth. However, some rare, reversible infantile mitochondrial diseases are caused by very specific defects of mitochondrial translation. An unbiased genetic approach (whole exome sequencing, RNA sequencing) combined with proteomics and functional studies revealed novel factors involved in mitochondrial translation which contribute to the clinical manifestation and recovery in these rare reversible mitochondrial conditions.
Collapse
|
15
|
Emerging therapies for mitochondrial diseases. Essays Biochem 2018; 62:467-481. [PMID: 29980632 DOI: 10.1042/ebc20170114] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 05/20/2018] [Accepted: 05/23/2018] [Indexed: 12/25/2022]
Abstract
For the vast majority of patients with mitochondrial diseases, only supportive and symptomatic therapies are available. However, in the last decade, due to extraordinary advances in defining the causes and pathomechanisms of these diverse disorders, new therapies are being developed in the laboratory and are entering human clinical trials. In this review, we highlight the current use of dietary supplement and exercise therapies as well as emerging therapies that may be broadly applicable across multiple mitochondrial diseases or tailored for specific disorders. Examples of non-tailored therapeutic targets include: activation of mitochondrial biogenesis, regulation of mitophagy and mitochondrial dynamics, bypass of biochemical defects, mitochondrial replacement therapy, and hypoxia. In contrast, tailored therapies are: scavenging of toxic compounds, deoxynucleoside and deoxynucleotide treatments, cell replacement therapies, gene therapy, shifting mitochondrial DNA mutation heteroplasmy, and stabilization of mutant mitochondrial transfer RNAs.
Collapse
|
16
|
Morrow EH, Camus MF. Mitonuclear epistasis and mitochondrial disease. Mitochondrion 2017; 35:119-122. [PMID: 28603048 DOI: 10.1016/j.mito.2017.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 06/06/2017] [Accepted: 06/06/2017] [Indexed: 12/01/2022]
Affiliation(s)
- Edward H Morrow
- School of Life Sciences, University of Sussex, Brighton BN1 9QG, United Kingdom.
| | - M Florencia Camus
- Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, United Kingdom
| |
Collapse
|
17
|
Nasca A, Scotton C, Zaharieva I, Neri M, Selvatici R, Magnusson OT, Gal A, Weaver D, Rossi R, Armaroli A, Pane M, Phadke R, Sarkozy A, Muntoni F, Hughes I, Cecconi A, Hajnóczky G, Donati A, Mercuri E, Zeviani M, Ferlini A, Ghezzi D. Recessive mutations in MSTO1 cause mitochondrial dynamics impairment, leading to myopathy and ataxia. Hum Mutat 2017; 38:970-977. [PMID: 28544275 PMCID: PMC5575512 DOI: 10.1002/humu.23262] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 05/10/2017] [Accepted: 05/12/2017] [Indexed: 12/30/2022]
Abstract
We report here the first families carrying recessive variants in the MSTO1 gene: compound heterozygous mutations were identified in two sisters and in an unrelated singleton case, who presented a multisystem complex phenotype mainly characterized by myopathy and cerebellar ataxia. Human MSTO1 is a poorly studied protein, suggested to have mitochondrial localization and to regulate morphology and distribution of mitochondria. As for other mutations affecting genes involved in mitochondrial dynamics, no biochemical defects typical of mitochondrial disorders were reported. Studies in patients’ fibroblasts revealed that MSTO1 protein levels were strongly reduced, the mitochondrial network was fragmented, and the fusion events among mitochondria were decreased, confirming the deleterious effect of the identified variants and the role of MSTO1 in modulating mitochondrial dynamics. We also found that MSTO1 is mainly a cytosolic protein. These findings indicate recessive mutations in MSTO1 as a new cause for inherited neuromuscular disorders with multisystem features.
Collapse
Affiliation(s)
- Alessia Nasca
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute Besta, Milan, Italy
| | - Chiara Scotton
- Medical Genetics Unit, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Irina Zaharieva
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Hospital, London, UK
| | - Marcella Neri
- Medical Genetics Unit, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Rita Selvatici
- Medical Genetics Unit, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | | | - Aniko Gal
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania.,Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - David Weaver
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Rachele Rossi
- Medical Genetics Unit, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Annarita Armaroli
- Medical Genetics Unit, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Marika Pane
- Neuropsichiatry Unit, Catholic University, Policlinico Gemelli, Rome, Italy
| | - Rahul Phadke
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Hospital, London, UK
| | - Anna Sarkozy
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Hospital, London, UK
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Hospital, London, UK
| | - Imelda Hughes
- Royal Manchester Children's Hospital, Manchester, UK
| | - Antonella Cecconi
- Pediatrics Medical Genetics, Hospital S. Maria Annunziata Bagno a Ripoli, Florence, Italy
| | - György Hajnóczky
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Alice Donati
- Unit of Metabolic and Muscular Diseases, Meyer Children Hospital, Florence, Italy
| | - Eugenio Mercuri
- Neuropsichiatry Unit, Catholic University, Policlinico Gemelli, Rome, Italy
| | | | - Alessandra Ferlini
- Medical Genetics Unit, Department of Medical Sciences, University of Ferrara, Ferrara, Italy.,Dubowitz Neuromuscular Centre, UCL Great Ormond Street Hospital, London, UK
| | - Daniele Ghezzi
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute Besta, Milan, Italy
| |
Collapse
|
18
|
Francisci S, Montanari A. Mitochondrial diseases: Yeast as a model for the study of suppressors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:666-673. [PMID: 28089773 DOI: 10.1016/j.bbamcr.2017.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 12/22/2016] [Accepted: 01/11/2017] [Indexed: 11/27/2022]
Abstract
Mitochondrial (mt) tRNA gene mutations are an important cause of human morbidity and are associated with different syndromes. We have previously shown that the mitochondrial protein synthesis elongation factor EF-Tu and isolated sequences from the carboxy-terminal domain of yeast and human mt leucyl-tRNA synthetases (LeuRS), have a wide range of suppression capability among different yeast mt tRNA mutants having defective respiratory phenotype. Here we show that the rescuing capability can be restricted to a specific sequence of six amino acids from the carboxy-terminal domain of mt LeuRS. On the other hand by overexpressing a mutated version of mt EF-Tu in a yeast strain deleted for the endogenous nuclear gene we identified the specific region involved in suppression. Results support the possibility that a small peptide could correct defects associated with many mt tRNA mutations, suggesting a novel therapy for mitochondrial diseases treatment. The involvement of the mt EF-Tu in cellular heat stress response has also been suggested.
Collapse
Affiliation(s)
- Silvia Francisci
- Department of Biology and Biotechnologies "Charles Darwin", Sapienza University of Rome, Piazzale Aldo Moro, 5, 00185 Rome, Italy.
| | - Arianna Montanari
- Department of Biology and Biotechnologies "Charles Darwin", Sapienza University of Rome, Piazzale Aldo Moro, 5, 00185 Rome, Italy; Pasteur Institute Italy - Cenci Bolognetti Foundation, Sapienza University of Rome, Viale Regina Elena, 291, 00161 Rome, Italy.
| |
Collapse
|
19
|
Surface Plasmon Resonance: A Useful Strategy for the Identification of Small Molecule Argonaute 2 Protein Binders. Methods Mol Biol 2017; 1517:223-237. [PMID: 27924486 DOI: 10.1007/978-1-4939-6563-2_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Surface plasmon resonance (SPR) is one of the most important techniques for the detection and the characterization of molecular interactions. SPR technology is a label-free approach for monitoring biomolecular interactions in real time. The binding of analytes to molecules immobilized on a thin metal film (ligand) determines a change in the refractive index and, therefore in the angle of extinction of light, is reflected when polarized light hits the film, monitored in real time as a change in the position of the dip in reflected intensity. Since SPR detects mass, the technique is label-free.Here, we describe the use of SPR techniques to study the interaction between Argonaute 2 and small molecular compounds selected by means of high-throughput docking screening.
Collapse
|
20
|
Nightingale H, Pfeffer G, Bargiela D, Horvath R, Chinnery PF. Emerging therapies for mitochondrial disorders. Brain 2016; 139:1633-48. [PMID: 27190030 PMCID: PMC4892756 DOI: 10.1093/brain/aww081] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/26/2016] [Indexed: 12/18/2022] Open
Abstract
Mitochondrial disorders are a diverse group of debilitating conditions resulting from nuclear and mitochondrial DNA mutations that affect multiple organs, often including the central and peripheral nervous system. Despite major advances in our understanding of the molecular mechanisms, effective treatments have not been forthcoming. For over five decades patients have been treated with different vitamins, co-factors and nutritional supplements, but with no proven benefit. There is therefore a clear need for a new approach. Several new strategies have been proposed acting at the molecular or cellular level. Whilst many show promise in vitro, the clinical potential of some is questionable. Here we critically appraise the most promising preclinical developments, placing the greatest emphasis on diseases caused by mitochondrial DNA mutations. With new animal and cellular models, longitudinal deep phenotyping in large patient cohorts, and growing interest from the pharmaceutical industry, the field is poised to make a breakthrough.
Collapse
Affiliation(s)
- Helen Nightingale
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK
| | - Gerald Pfeffer
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK Department of Clinical Neurosciences, University of Calgary, Calgary, Canada Hotchkiss Brain Institute, at the University of Calgary, Calgary, Canada
| | - David Bargiela
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK
| | - Rita Horvath
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK
| | - Patrick F Chinnery
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK MRC-Mitochondrial Biology Unit, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, CB2 0QQ, UK
| |
Collapse
|
21
|
Perli E, Fiorillo A, Giordano C, Pisano A, Montanari A, Grazioli P, Campese AF, Di Micco P, Tuppen HA, Genovese I, Poser E, Preziuso C, Taylor RW, Morea V, Colotti G, d'Amati G. Short peptides from leucyl-tRNA synthetase rescue disease-causing mitochondrial tRNA point mutations. Hum Mol Genet 2016; 25:903-15. [PMID: 26721932 PMCID: PMC4754043 DOI: 10.1093/hmg/ddv619] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 12/18/2015] [Indexed: 01/11/2023] Open
Abstract
Mutations in mitochondrial (mt) genes coding for mt-tRNAs are responsible for a range of syndromes, for which no effective treatment is available. We recently showed that the carboxy-terminal domain (Cterm) of human mt-leucyl tRNA synthetase rescues the pathologic phenotype associated either with the m.3243A>G mutation in mt-tRNA(Leu(UUR)) or with mutations in the mt-tRNA(Ile), both of which are aminoacylated by Class I mt-aminoacyl-tRNA synthetases (mt-aaRSs). Here we show, by using the human transmitochondrial cybrid model, that the Cterm is also able to improve the phenotype caused by the m.8344A>G mutation in mt-tRNA(Lys), aminoacylated by a Class II aaRS. Importantly, we demonstrate that the same rescuing ability is retained by two Cterm-derived short peptides, β30_31 and β32_33, which are effective towards both the m.8344A>G and the m.3243A>G mutations. Furthermore, we provide in vitro evidence that these peptides bind with high affinity wild-type and mutant human mt-tRNA(Leu(UUR)) and mt-tRNA(Lys), and stabilize mutant mt-tRNA(Leu(UUR)). In conclusion, we demonstrate that small Cterm-derived peptides can be effective tools to rescue cellular defects caused by mutations in a wide range of mt-tRNAs.
Collapse
Affiliation(s)
- Elena Perli
- Department of Radiology, Oncology and Pathology
| | | | | | | | - Arianna Montanari
- Department of Biology and Biotechnologies 'Charles Darwin' and Pasteur Institute-Cenci Bolognetti Foundation, Rome 00161, Italy
| | - Paola Grazioli
- Department of Molecular Medicine, Sapienza University of Rome, Rome 00161, Italy
| | - Antonio F Campese
- Department of Molecular Medicine, Sapienza University of Rome, Rome 00161, Italy
| | | | - Helen A Tuppen
- Wellcome Trust Center for Mitochondrial Research, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne NE1 7RU, UK and
| | | | - Elena Poser
- Department of Biochemical Sciences "A. Rossi Fanelli"
| | | | - Robert W Taylor
- Wellcome Trust Center for Mitochondrial Research, Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne NE1 7RU, UK and
| | - Veronica Morea
- National Research Council of Italy, Institute of Molecular Biology and Pathology, Rome 00185, Italy
| | - Gianni Colotti
- National Research Council of Italy, Institute of Molecular Biology and Pathology, Rome 00185, Italy
| | - Giulia d'Amati
- Department of Radiology, Oncology and Pathology, Pasteur Institute-Cenci Bolognetti Foundation, Rome 00161, Italy,
| |
Collapse
|
22
|
Ficociello G, Salemme A, Uccelletti D, Fiorito S, Togna AR, Vallan L, González-Domínguez JM, Da Ros T, Francisci S, Montanari A. Evaluation of the efficacy of carbon nanotubes for delivering peptides into mitochondria. RSC Adv 2016. [DOI: 10.1039/c6ra14254k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Future therapy for mitochondrial pathologies: CKKSFLSPRTALINFLVK peptide from mitochondrial-LeuRS has a mitochondrial targeting activity when conjugated with multi-walled carbon nanotubes.
Collapse
Affiliation(s)
- Graziella Ficociello
- Department of Biology and Biotechnologies “Charles Darwin”
- Sapienza University of Rome
- 5-00185 Rome
- Italy
| | - Adele Salemme
- Department of Physiology and Pharmacology “Vittorio Erspamer”
- Sapienza University of Rome
- 5-00185 Rome
- Italy
| | - Daniela Uccelletti
- Department of Biology and Biotechnologies “Charles Darwin”
- Sapienza University of Rome
- 5-00185 Rome
- Italy
| | - Silvana Fiorito
- Institute of Translational Pharmacology – CNR
- 100-00133 Rome
- Italy
| | - Anna Rita Togna
- Department of Physiology and Pharmacology “Vittorio Erspamer”
- Sapienza University of Rome
- 5-00185 Rome
- Italy
| | - Lorenzo Vallan
- INSTM Unit of Trieste
- Department of Chemical and Pharmaceutical Sciences
- University of Trieste
- 1-34127 Trieste
- Italy
| | - Jose M. González-Domínguez
- INSTM Unit of Trieste
- Department of Chemical and Pharmaceutical Sciences
- University of Trieste
- 1-34127 Trieste
- Italy
| | - Tatiana Da Ros
- INSTM Unit of Trieste
- Department of Chemical and Pharmaceutical Sciences
- University of Trieste
- 1-34127 Trieste
- Italy
| | - Silvia Francisci
- Department of Biology and Biotechnologies “Charles Darwin”
- Sapienza University of Rome
- 5-00185 Rome
- Italy
| | - Arianna Montanari
- Department of Biology and Biotechnologies “Charles Darwin”
- Sapienza University of Rome
- 5-00185 Rome
- Italy
- Pasteur Institute – Cenci Bolognetti Foundation
| |
Collapse
|
23
|
Brown TA, Tkachuk AN, Clayton DA. Mitochondrial Transcription Factor A (TFAM) Binds to RNA Containing 4-Way Junctions and Mitochondrial tRNA. PLoS One 2015; 10:e0142436. [PMID: 26545237 PMCID: PMC4636309 DOI: 10.1371/journal.pone.0142436] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/21/2015] [Indexed: 11/26/2022] Open
Abstract
Mitochondrial DNA (mtDNA) is maintained within nucleoprotein complexes known as nucleoids. These structures are highly condensed by the DNA packaging protein, mitochondrial Transcription Factor A (TFAM). Nucleoids also include RNA, RNA:DNA hybrids, and are associated with proteins involved with RNA processing and mitochondrial ribosome biogenesis. Here we characterize the ability of TFAM to bind various RNA containing substrates in order to determine their role in TFAM distribution and function within the nucleoid. We find that TFAM binds to RNA-containing 4-way junctions but does not bind appreciably to RNA hairpins, internal loops, or linear RNA:DNA hybrids. Therefore the RNA within nucleoids largely excludes TFAM, and its distribution is not grossly altered with removal of RNA. Within the cell, TFAM binds to mitochondrial tRNAs, consistent with our RNA 4-way junction data. Kinetic binding assays and RNase-insensitive TFAM distribution indicate that DNA remains the preferred substrate within the nucleoid. However, TFAM binds to tRNA with nanomolar affinity and these complexes are not rare. TFAM-immunoprecipitated tRNAs have processed ends, suggesting that binding is not specific to RNA precursors. The amount of each immunoprecipitated tRNA is not well correlated with tRNA celluar abundance, indicating unequal TFAM binding preferences. TFAM-mt-tRNA interaction suggests potentially new functions for this protein.
Collapse
Affiliation(s)
- Timothy A. Brown
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, United States of America
- * E-mail:
| | - Ariana N. Tkachuk
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, United States of America
| | - David A. Clayton
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia, United States of America
| |
Collapse
|
24
|
Lightowlers RN, Taylor RW, Turnbull DM. Mutations causing mitochondrial disease: What is new and what challenges remain? Science 2015; 349:1494-9. [PMID: 26404827 DOI: 10.1126/science.aac7516] [Citation(s) in RCA: 211] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mitochondrial diseases are among the most common and most complex of all inherited genetic diseases. The involvement of both the mitochondrial and nuclear genome presents unique challenges, but despite this there have been some remarkable advances in our knowledge of mitochondrial diseases over the past few years. A greater understanding of mitochondrial genetics has led to improved diagnosis as well as novel ways to prevent transmission of severe mitochondrial disease. These and other advances have had a major impact on patient care, but considerable challenges remain, particularly in the areas of therapies for those patients manifesting clinical symptoms associated with mitochondrial dysfunction and the tissue specificity seen in many mitochondrial disorders. This review highlights some important recent advances in mitochondrial disease but also stresses the areas where progress is essential.
Collapse
Affiliation(s)
- Robert N Lightowlers
- Wellcome Trust Centre for Mitochondrial Research, Institute for Cell and Molecular Biosciences and Institute of Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute for Cell and Molecular Biosciences and Institute of Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Doug M Turnbull
- Wellcome Trust Centre for Mitochondrial Research, Institute for Cell and Molecular Biosciences and Institute of Neuroscience, Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| |
Collapse
|
25
|
Rahman S. Emerging aspects of treatment in mitochondrial disorders. J Inherit Metab Dis 2015; 38:641-53. [PMID: 25962587 DOI: 10.1007/s10545-015-9855-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 11/26/2022]
Abstract
Mitochondrial diseases are clinically, biochemically and genetically heterogeneous disorders of two genomes, for which effective curative therapies are currently lacking. With the exception of a few rare vitamin/cofactor responsive conditions (including ACAD9 deficiency, disorders of coenzyme Q(10) biosynthesis, and Leigh syndrome caused by mutations in the SLC19A3 transporter), the mainstay of treatment for the vast majority of patients involves supportive measures. The search for a cure for mitochondrial disease is the subject of intensive research efforts by many investigators across the globe, but the goal remains elusive. The clinical and genetic heterogeneity, multisystemic nature of many of these disorders, unpredictable natural course, relative inaccessibility of the mitochondrion and lack of validated, clinically meaningful outcome measures, have all presented great challenges to the design of rigorous clinical trials. This review discusses barriers to developing effective therapies for mitochondrial disease, models for evaluating the efficacy of novel treatments and summarises the most promising emerging therapies in six key areas: 1) antioxidant approaches; 2) stimulating mitochondrial biogenesis; 3) targeting mitochondrial membrane lipids, dynamics and mitophagy; 4) replacement therapy; 5) cell-based therapies; and 6) gene therapy approaches for both mtDNA and nuclear-encoded defects of mitochondrial metabolism.
Collapse
Affiliation(s)
- Shamima Rahman
- Mitochondrial Research Group, Genetics and Genomic Medicine, Institute of Child Health, University College London and Metabolic Unit, Great Ormond Street Hospital, 30 Guilford Street, London, WC1N 1EH, UK,
| |
Collapse
|
26
|
Chen C, Chen Y, Guan MX. A peep into mitochondrial disorder: multifaceted from mitochondrial DNA mutations to nuclear gene modulation. Protein Cell 2015; 6:862-70. [PMID: 26084519 PMCID: PMC4656216 DOI: 10.1007/s13238-015-0175-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/17/2015] [Indexed: 02/06/2023] Open
Abstract
Mitochondrial genome is responsible for multiple human diseases in a maternal inherited pattern, yet phenotypes of patients in a same pedigree frequently vary largely. Genes involving in epigenetic modification, RNA processing, and other biological pathways, rather than “threshold effect” and environmental factors, provide more specific explanation to the aberrant phenotype. Thus, the double hit theory, mutations both in mitochondrial DNA and modifying genes aggravating the symptom, throws new light on mitochondrial dysfunction processes. In addition, mitochondrial retrograde signaling pathway that leads to reconfiguration of cell metabolism to adapt defects in mitochondria may as well play an active role. Here we review selected examples of modifier genes and mitochondrial retrograde signaling in mitochondrial disorders, which refine our understanding and will guide the rational design of clinical therapies.
Collapse
Affiliation(s)
- Chao Chen
- School of Medicine, Institute of Genetics, Zhejiang University, Hangzhou, 310058, China
| | - Ye Chen
- School of Medicine, Institute of Genetics, Zhejiang University, Hangzhou, 310058, China. .,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310058, China.
| | - Min-Xin Guan
- School of Medicine, Institute of Genetics, Zhejiang University, Hangzhou, 310058, China.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310058, China
| |
Collapse
|
27
|
Holmbeck MA, Donner JR, Villa-Cuesta E, Rand DM. A Drosophila model for mito-nuclear diseases generated by an incompatible interaction between tRNA and tRNA synthetase. Dis Model Mech 2015; 8:843-54. [PMID: 26035388 PMCID: PMC4527286 DOI: 10.1242/dmm.019323] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 04/23/2015] [Indexed: 12/30/2022] Open
Abstract
Communication between the mitochondrial and nuclear genomes is vital for cellular function. The assembly of mitochondrial enzyme complexes, which produce the majority of cellular energy, requires the coordinated expression and translation of both mitochondrially and nuclear-encoded proteins. The joint genetic architecture of this system complicates the basis of mitochondrial diseases, and mutations both in mitochondrial DNA (mtDNA)- and nuclear-encoded genes have been implicated in mitochondrial dysfunction. Previously, in a set of mitochondrial-nuclear introgression strains, we characterized a dual genome epistasis in which a naturally occurring mutation in the Drosophila simulans simw(501) mtDNA-encoded transfer RNA (tRNA) for tyrosine (tRNA(Tyr)) interacts with a mutation in the nuclear-encoded mitochondrially localized tyrosyl-tRNA synthetase from Drosophila melanogaster. Here, we show that the incompatible mitochondrial-nuclear combination results in locomotor defects, reduced mitochondrial respiratory capacity, decreased oxidative phosphorylation (OXPHOS) enzyme activity and severe alterations in mitochondrial morphology. Transgenic rescue strains containing nuclear variants of the tyrosyl-tRNA synthetase are sufficient to rescue many of the deleterious phenotypes identified when paired with the simw(501) mtDNA. However, the severity of this defective mito-nuclear interaction varies across traits and genetic backgrounds, suggesting that the impact of mitochondrial dysfunction might be tissue specific. Because mutations in mitochondrial tRNA(Tyr) are associated with exercise intolerance in humans, this mitochondrial-nuclear introgression model in Drosophila provides a means to dissect the molecular basis of these, and other, mitochondrial diseases that are a consequence of the joint genetic architecture of mitochondrial function.
Collapse
Affiliation(s)
- Marissa A Holmbeck
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, USA
| | - Julia R Donner
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
| | | | - David M Rand
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
| |
Collapse
|
28
|
Abstract
Because of their high-energy metabolism, neurons are strictly dependent on mitochondria, which generate cellular ATP through oxidative phosphorylation. The mitochondrial genome encodes for critical components of the oxidative phosphorylation pathway machinery, and therefore, mutations in mitochondrial DNA (mtDNA) cause energy production defects that frequently have severe neurological manifestations. Here, we review the principles of mitochondrial genetics and focus on prototypical mitochondrial diseases to illustrate how primary defects in mtDNA or secondary defects in mtDNA due to nuclear genome mutations can cause prominent neurological and multisystem features. In addition, we discuss the pathophysiological mechanisms underlying mitochondrial diseases, the cellular mechanisms that protect mitochondrial integrity, and the prospects for therapy.
Collapse
Affiliation(s)
- Valerio Carelli
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy; Neurology Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - David C Chan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
| |
Collapse
|
29
|
Giordano C, Morea V, Perli E, d'Amati G. The phenotypic expression of mitochondrial tRNA-mutations can be modulated by either mitochondrial leucyl-tRNA synthetase or the C-terminal domain thereof. Front Genet 2015; 6:113. [PMID: 25852750 PMCID: PMC4370040 DOI: 10.3389/fgene.2015.00113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 03/04/2015] [Indexed: 11/23/2022] Open
Abstract
Mutations in mitochondrial (mt) DNA determine important human diseases. The majority of the known pathogenic mutations are located in transfer RNA (tRNA) genes and are responsible for a wide range of currently untreatable disorders. Experimental evidence both in yeast and in human cells has shown that the detrimental effects of mt-tRNA point mutations can be attenuated by increasing the expression of the cognate mt-aminoacyl-tRNA synthetases (aaRSs). In addition, constitutive high levels of isoleucyl-tRNA syntethase have been shown to reduce the penetrance of a homoplasmic mutation in mt-tRNAIle in a small kindred. More recently, we showed that the isolated carboxy-terminal domain of human mt-leucyl tRNA synthetase (LeuRS-Cterm) localizes to mitochondria and ameliorates the energetic defect in transmitochondrial cybrids carrying mutations either in the cognate mt-tRNALeu(UUR) or in the non-cognate mt-tRNAIle gene. Since the mt-LeuRS-Cterm does not possess catalytic activity, its rescuing ability is most likely mediated by a chaperon-like effect, consisting in the stabilization of the tRNA structure altered by the mutation. All together, these observations open potential therapeutic options for mt-tRNA mutations-associated diseases.
Collapse
Affiliation(s)
- Carla Giordano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome Rome, Italy
| | - Veronica Morea
- National Research Council of Italy, Institute of Molecular Biology and Pathology, Department of Biochemical Sciences, Sapienza University of Rome Rome, Italy
| | - Elena Perli
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome Rome, Italy
| | - Giulia d'Amati
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome Rome, Italy ; Pasteur Institute-Cenci Bolognetti Foundation Rome, Italy
| |
Collapse
|
30
|
Powell CA, Nicholls TJ, Minczuk M. Nuclear-encoded factors involved in post-transcriptional processing and modification of mitochondrial tRNAs in human disease. Front Genet 2015; 6:79. [PMID: 25806043 PMCID: PMC4354410 DOI: 10.3389/fgene.2015.00079] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/16/2015] [Indexed: 11/29/2022] Open
Abstract
The human mitochondrial genome (mtDNA) encodes 22 tRNAs (mt-tRNAs) that are necessary for the intraorganellar translation of the 13 mtDNA-encoded subunits of the mitochondrial respiratory chain complexes. Maturation of mt-tRNAs involves 5′ and 3′ nucleolytic excision from precursor RNAs, as well as extensive post-transcriptional modifications. Recent data suggest that over 7% of all mt-tRNA residues in mammals undergo post-transcriptional modification, with over 30 different modified mt-tRNA positions so far described. These processing and modification steps are necessary for proper mt-tRNA function, and are performed by dedicated, nuclear-encoded enzymes. Recent growing evidence suggests that mutations in these nuclear genes (nDNA), leading to incorrect maturation of mt-tRNAs, are a cause of human mitochondrial disease. Furthermore, mtDNA mutations in mt-tRNA genes, which may also affect mt-tRNA function, processing, and modification, are also frequently associated with human disease. In theory, all pathogenic mt-tRNA variants should be expected to affect only a single process, which is mitochondrial translation, albeit to various extents. However, the clinical manifestations of mitochondrial disorders linked to mutations in mt-tRNAs are extremely heterogeneous, ranging from defects of a single tissue to complex multisystem disorders. This review focuses on the current knowledge of nDNA coding for proteins involved in mt-tRNA maturation that have been linked to human mitochondrial pathologies. We further discuss the possibility that tissue specific regulation of mt-tRNA modifying enzymes could play an important role in the clinical heterogeneity observed for mitochondrial diseases caused by mutations in mt-tRNA genes.
Collapse
Affiliation(s)
- Christopher A Powell
- Mitochondrial Genetics, Mitochondrial Biology Unit, Medical Research Council, Cambridge, UK
| | - Thomas J Nicholls
- Mitochondrial Genetics, Mitochondrial Biology Unit, Medical Research Council, Cambridge, UK
| | - Michal Minczuk
- Mitochondrial Genetics, Mitochondrial Biology Unit, Medical Research Council, Cambridge, UK
| |
Collapse
|
31
|
Viscomi C, Bottani E, Zeviani M. Emerging concepts in the therapy of mitochondrial disease. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:544-57. [PMID: 25766847 DOI: 10.1016/j.bbabio.2015.03.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 02/15/2015] [Accepted: 03/02/2015] [Indexed: 01/07/2023]
Abstract
Mitochondrial disorders are an important group of genetic conditions characterized by impaired oxidative phosphorylation. Mitochondrial disorders come with an impressive variability of symptoms, organ involvement, and clinical course, which considerably impact the quality of life and quite often shorten the lifespan expectancy. Although the last 20 years have witnessed an exponential increase in understanding the genetic and biochemical mechanisms leading to disease, this has not resulted in the development of effective therapeutic approaches, amenable of improving clinical course and outcome of these conditions to any significant extent. Therapeutic options for mitochondrial diseases still remain focused on supportive interventions aimed at relieving complications. However, new therapeutic strategies have recently been emerging, some of which have shown potential efficacy at the pre-clinical level. This review will present the state of the art on experimental therapy for mitochondrial disorders.
Collapse
Affiliation(s)
- Carlo Viscomi
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
| | | | - Massimo Zeviani
- Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology IRCCS, 20133 Milan, Italy; MRC-Mitochondrial Biology Unit, Cambridge CB2 0XY, UK.
| |
Collapse
|
32
|
Turnbull DM, Rustin P. Genetic and biochemical intricacy shapes mitochondrial cytopathies. Neurobiol Dis 2015; 92:55-63. [PMID: 25684538 DOI: 10.1016/j.nbd.2015.02.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/22/2015] [Accepted: 02/03/2015] [Indexed: 12/17/2022] Open
Abstract
The major progress made in the identification of the molecular bases of mitochondrial disease has revealed the huge diversity of their origin. Today up to 300 mutations were identified in the mitochondrial genome and about 200 nuclear genes are possibly mutated. In this review, we highlight a number of features specific to mitochondria which possibly participate in the complexity of these diseases. These features include both the complexity of mitochondrial genetics and the multiplicity of the roles ensured by the organelles in numerous aspects of cell life and death. This spectacular complexity presumably accounts for the present lack of an efficient therapy in the vast majority of cases.
Collapse
Affiliation(s)
- Douglass M Turnbull
- Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Newcastle University, Framlington Road, Newcastle upon Tyne NE2 4HH, UK
| | - Pierre Rustin
- INSERM UMR 1141, Hôpital Robert Debré, Paris, France; Université Paris 7, Faculté de Médecine Denis Diderot, Paris, France.
| |
Collapse
|
33
|
|
34
|
Di Micco P, Fazzi D'Orsi M, Morea V, Frontali L, Francisci S, Montanari A. The yeast model suggests the use of short peptides derived from mt LeuRS for the therapy of diseases due to mutations in several mt tRNAs. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:3065-74. [PMID: 25261707 DOI: 10.1016/j.bbamcr.2014.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 09/09/2014] [Accepted: 09/11/2014] [Indexed: 01/23/2023]
Abstract
We have previously established a yeast model of mitochondrial (mt) diseases. We showed that defective respiratory phenotypes due to point-mutations in mt tRNA(Leu(UUR)), tRNA(Ile) and tRNA(Val) could be relieved by overexpression of both cognate and non-cognate nuclearly encoded mt aminoacyl-tRNA synthetases (aaRS) LeuRS, IleRS and ValRS. More recently, we showed that the isolated carboxy-terminal domain (Cterm) of yeast mt LeuRS, and even short peptides derived from the human Cterm, have the same suppressing abilities as the whole enzymes. In this work, we extend these results by investigating the activity of a number of mt aaRS from either class I or II towards a panel of mt tRNAs. The Cterm of both human and yeast mt LeuRS has the same spectrum of activity as mt aaRS belonging to class I and subclass a, which is the most extensive among the whole enzymes. Yeast Cterm is demonstrated to be endowed with mt targeting activity. Importantly, peptide fragments β30_31 and β32_33, derived from the human Cterm, have even higher efficiency as well as wider spectrum of activity, thus opening new avenues for therapeutic intervention. Bind-shifting experiments show that the β30_31 peptide directly interacts with human mt tRNA(Leu(UUR)) and tRNA(Ile), suggesting that the rescuing activity of isolated peptide fragments is mediated by a chaperone-like mechanism. Wide-range suppression appears to be idiosyncratic of LeuRS and its fragments, since it is not shared by Cterminal regions derived from human mt IleRS or ValRS, which are expected to have very different structures and interactions with tRNAs.
Collapse
Affiliation(s)
- Patrizio Di Micco
- Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy
| | - Mario Fazzi D'Orsi
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy
| | - Veronica Morea
- National Research Council of Italy (CNR) - Institute of Biology, Molecular Medicine and Nanobiotechnology (IBMN), Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy
| | - Laura Frontali
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy; Pasteur Institute - Cenci Bolognetti Foundation, Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy
| | - Silvia Francisci
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy; Pasteur Institute - Cenci Bolognetti Foundation, Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy
| | - Arianna Montanari
- Department of Biology and Biotechnologies "C. Darwin", Sapienza University of Rome, Piazzale A. Moro 5, 00185 Rome, Italy.
| |
Collapse
|
35
|
Abbott JA, Francklyn CS, Robey-Bond SM. Transfer RNA and human disease. Front Genet 2014; 5:158. [PMID: 24917879 PMCID: PMC4042891 DOI: 10.3389/fgene.2014.00158] [Citation(s) in RCA: 149] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 05/14/2014] [Indexed: 12/25/2022] Open
Abstract
Pathological mutations in tRNA genes and tRNA processing enzymes are numerous and result in very complicated clinical phenotypes. Mitochondrial tRNA (mt-tRNA) genes are “hotspots” for pathological mutations and over 200 mt-tRNA mutations have been linked to various disease states. Often these mutations prevent tRNA aminoacylation. Disrupting this primary function affects protein synthesis and the expression, folding, and function of oxidative phosphorylation enzymes. Mitochondrial tRNA mutations manifest in a wide panoply of diseases related to cellular energetics, including COX deficiency (cytochrome C oxidase), mitochondrial myopathy, MERRF (Myoclonic Epilepsy with Ragged Red Fibers), and MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes). Diseases caused by mt-tRNA mutations can also affect very specific tissue types, as in the case of neurosensory non-syndromic hearing loss and pigmentary retinopathy, diabetes mellitus, and hypertrophic cardiomyopathy. Importantly, mitochondrial heteroplasmy plays a role in disease severity and age of onset as well. Not surprisingly, mutations in enzymes that modify cytoplasmic and mitochondrial tRNAs are also linked to a diverse range of clinical phenotypes. In addition to compromised aminoacylation of the tRNAs, mutated modifying enzymes can also impact tRNA expression and abundance, tRNA modifications, tRNA folding, and even tRNA maturation (e.g., splicing). Some of these pathological mutations in tRNAs and processing enzymes are likely to affect non-canonical tRNA functions, and contribute to the diseases without significantly impacting on translation. This chapter will review recent literature on the relation of mitochondrial and cytoplasmic tRNA, and enzymes that process tRNAs, to human disease. We explore the mechanisms involved in the clinical presentation of these various diseases with an emphasis on neurological disease.
Collapse
Affiliation(s)
- Jamie A Abbott
- Department of Biochemistry, College of Medicine, University of Vermont Burlington, VT, USA
| | | | - Susan M Robey-Bond
- Department of Biochemistry, College of Medicine, University of Vermont Burlington, VT, USA
| |
Collapse
|
36
|
Tyynismaa H, Schon EA. Mixing and matching mitochondrial aminoacyl synthetases and their tRNAs: a new way to treat respiratory chain disorders? EMBO Mol Med 2014; 6:155-7. [PMID: 24473201 PMCID: PMC3927951 DOI: 10.1002/emmm.201303586] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Mutations in mitochondrial DNA are an important cause of human disease and from a therapeutic standpoint, these disorders are currently untreatable. New studies now show that a non‐cognate mitochondrial aminoacyl tRNA synthetase can overcome the respiratory defect caused by an mt‐tRNA mutation and that the isolated carboxy‐terminal domain of human mt‐leucyl tRNA synthetase can ameliorate the pathologic phenotype.
Collapse
Affiliation(s)
- Henna Tyynismaa
- Research Programs Unit Molecular Neurology, Biomedicum Helsinki, Helsinki, Finland
| | | |
Collapse
|
37
|
Pathological Mutations of the Mitochondrial Human Genome: the Instrumental Role of the Yeast S. cerevisiae. Diseases 2014. [DOI: 10.3390/diseases2010024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|