1
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Sun X, Singla-Rastogi M, Wang J, Zhao C, Wang X, Li P. The uS10c-BPG2 module mediates ribosomal RNA processing in chloroplast nucleoids. Nucleic Acids Res 2024; 52:7893-7909. [PMID: 38686791 PMCID: PMC11260468 DOI: 10.1093/nar/gkae339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/09/2024] [Accepted: 04/17/2024] [Indexed: 05/02/2024] Open
Abstract
In plant chloroplasts, certain ribosomal proteins (RPs) and ribosome biogenesis factors (RBFs) are present in nucleoids, implying an association between nucleoids and ribosome biogenesis. In Arabidopsis, the YqeH-type GTPase Brassinazole-Insensitive Pale Green2 (BPG2) is a chloroplast nucleoid-associated RBF. Here, we investigated the relationship between nucleoids and BPG2-involved ribosome biogenesis steps by exploring how BPG2 targets ribosomes. Our findings demonstrate that BPG2 interacts with an essential plastid RP, uS10c, in chloroplast nucleoids in a ribosomal RNA (rRNA)-independent manner. We also discovered that uS10c is a haploinsufficient gene, as the heterozygous deletion of this gene leads to variegated shoots and chlorophyll aggregation. uS10c is integrated into 30S ribosomal particles when rRNA is relatively exposed and also exists in polysome fractions. In contrast, BPG2 exclusively associates with 30S ribosomal particles. Notably, the interaction between BPG2 and 30S particles is influenced by the absence of uS10c, resulting in BPG2 diffusing in chloroplasts instead of targeting nucleoids. Further, our results reveal that the loss of BPG2 function and the heterozygous deletion of uS10c impair the processing of 16S and 23S-4.5S rRNAs, reduce plastid protein accumulation, and trigger the plastid signaling response. Together, these findings indicate that the uS10c-BPG2 module mediates ribosome biogenesis in chloroplast nucleoids.
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Affiliation(s)
- Xueping Sun
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
- College of Life Sciences, Shandong Normal University, Jinan, Shandong 250014, PR China
| | | | - Jingwen Wang
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
- College of Life Sciences, Shandong Normal University, Jinan, Shandong 250014, PR China
| | - Chuanzhi Zhao
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
| | - Xingjun Wang
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
| | - Pengcheng Li
- Institute of Crop Germplasm Resources (Biotechnology Research Center), Shandong Academy of Agricultural Sciences; Shandong Provincial Key Laboratory of Crop Genetic Improvement, Ecology and Physiology, Jinan, Shandong 250100, PR China
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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2
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Meynier V, Hardwick SW, Catala M, Roske JJ, Oerum S, Chirgadze DY, Barraud P, Yue WW, Luisi BF, Tisné C. Structural basis for human mitochondrial tRNA maturation. Nat Commun 2024; 15:4683. [PMID: 38824131 PMCID: PMC11144196 DOI: 10.1038/s41467-024-49132-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 05/21/2024] [Indexed: 06/03/2024] Open
Abstract
The human mitochondrial genome is transcribed into two RNAs, containing mRNAs, rRNAs and tRNAs, all dedicated to produce essential proteins of the respiratory chain. The precise excision of tRNAs by the mitochondrial endoribonucleases (mt-RNase), P and Z, releases all RNA species from the two RNA transcripts. The tRNAs then undergo 3'-CCA addition. In metazoan mitochondria, RNase P is a multi-enzyme assembly that comprises the endoribonuclease PRORP and a tRNA methyltransferase subcomplex. The requirement for this tRNA methyltransferase subcomplex for mt-RNase P cleavage activity, as well as the mechanisms of pre-tRNA 3'-cleavage and 3'-CCA addition, are still poorly understood. Here, we report cryo-EM structures that visualise four steps of mitochondrial tRNA maturation: 5' and 3' tRNA-end processing, methylation and 3'-CCA addition, and explain the defined sequential order of the tRNA processing steps. The methyltransferase subcomplex recognises the pre-tRNA in a distinct mode that can support tRNA-end processing and 3'-CCA addition, likely resulting from an evolutionary adaptation of mitochondrial tRNA maturation complexes to the structurally-fragile mitochondrial tRNAs. This subcomplex can also ensure a tRNA-folding quality-control checkpoint before the sequential docking of the maturation enzymes. Altogether, our study provides detailed molecular insight into RNA-transcript processing and tRNA maturation in human mitochondria.
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Affiliation(s)
- Vincent Meynier
- Expression Génétique Microbienne, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique (IBPC), 75005, Paris, France
| | - Steven W Hardwick
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Marjorie Catala
- Expression Génétique Microbienne, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique (IBPC), 75005, Paris, France
| | - Johann J Roske
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Stephanie Oerum
- Expression Génétique Microbienne, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique (IBPC), 75005, Paris, France
| | - Dimitri Y Chirgadze
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Pierre Barraud
- Expression Génétique Microbienne, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique (IBPC), 75005, Paris, France
| | - Wyatt W Yue
- Centre for Medicines Discovery, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, OX3 7DQ, UK
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Ben F Luisi
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Carine Tisné
- Expression Génétique Microbienne, Université Paris Cité, CNRS, Institut de Biologie Physico-Chimique (IBPC), 75005, Paris, France.
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3
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Sridhara S. Multiple structural flavors of RNase P in precursor tRNA processing. WILEY INTERDISCIPLINARY REVIEWS. RNA 2024; 15:e1835. [PMID: 38479802 DOI: 10.1002/wrna.1835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 06/06/2024]
Abstract
The precursor transfer RNAs (pre-tRNAs) require extensive processing to generate mature tRNAs possessing proper fold, structural stability, and functionality required to sustain cellular viability. The road to tRNA maturation follows an ordered process: 5'-processing, 3'-processing, modifications at specific sites, if any, and 3'-CCA addition before aminoacylation and recruitment to the cellular protein synthesis machinery. Ribonuclease P (RNase P) is a universally conserved endonuclease in all domains of life, performing the hydrolysis of pre-tRNA sequences at the 5' end by the removal of phosphodiester linkages between nucleotides at position -1 and +1. Except for an archaeal species: Nanoarchaeum equitans where tRNAs are transcribed from leaderless-position +1, RNase P is indispensable for life and displays fundamental variations in terms of enzyme subunit composition, mechanism of substrate recognition and active site architecture, utilizing in all cases a two metal ion-mediated conserved catalytic reaction. While the canonical RNA-based ribonucleoprotein RNase P has been well-known to occur in bacteria, archaea, and eukaryotes, the occurrence of RNA-free protein-only RNase P in eukaryotes and RNA-free homologs of Aquifex RNase P in prokaryotes has been discovered more recently. This review aims to provide a comprehensive overview of structural diversity displayed by various RNA-based and RNA-free RNase P holoenzymes towards harnessing critical RNA-protein and protein-protein interactions in achieving conserved pre-tRNA processing functionality. Furthermore, alternate roles and functional interchangeability of RNase P are discussed in the context of its employability in several clinical and biotechnological applications. This article is categorized under: RNA Processing > tRNA Processing RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.
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Affiliation(s)
- Sagar Sridhara
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
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4
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Caicedo A, Morales E, Moyano A, Peñaherrera S, Peña-Cisneros J, Benavides-Almeida A, Pérez-Meza ÁA, Haro-Vinueza A, Ruiz C, Robayo P, Tenesaca D, Barba D, Zambrano K, Castañeda V, Singh KK. Powering prescription: Mitochondria as "Living Drugs" - Definition, clinical applications, and industry advancements. Pharmacol Res 2024; 199:107018. [PMID: 38013162 DOI: 10.1016/j.phrs.2023.107018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 11/22/2023] [Accepted: 11/24/2023] [Indexed: 11/29/2023]
Abstract
Mitochondria's role as engines and beacons of metabolism and determinants of cellular health is being redefined through their therapeutic application as "Living Drugs" (LDs). Artificial mitochondrial transfer/transplant (AMT/T), encompassing various techniques to modify, enrich, or restore mitochondria in cells and tissues, is revolutionizing acellular therapies and the future of medicine. This article proposes a necessary definition for LDs within the Advanced Therapeutic Medicinal Products (ATMPs) framework. While recognizing different types of LDs as ATMPs, such as mesenchymal stem cells (MSCs) and chimeric antigen receptor T (CAR T) cells, we focus on mitochondria due to their unique attributes that distinguish them from traditional cell therapies. These attributes include their inherent living nature, diverse sources, industry applicability, validation, customizability for therapeutic needs, and their capability to adapt and respond within recipient cells. We trace the journey from initial breakthroughs in AMT/T to the current state-of-the-art applications by emerging innovative companies, highlighting the need for manufacturing standards to navigate the transition of mitochondrial therapies from concept to clinical practice. By providing a comprehensive overview of the scientific, clinical, and commercial landscape of mitochondria as LDs, this article contributes to the essential dialogue among regulatory agencies, academia, and industry to shape their future in medicine.
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Affiliation(s)
- Andrés Caicedo
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador; Sistemas Médicos SIME, Universidad San Francisco de Quito, Quito, Ecuador.
| | - Emilia Morales
- Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador; Biología, Colegio de Ciencias Biológicas y Ambientales COCIBA, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Aldana Moyano
- Mito-Act Research Consortium, Quito, Ecuador; Instituto de investigaciones biotecnológicas IIB, Universidad Nacional de San Martín, Buenos Aires, Argentina
| | - Sebastian Peñaherrera
- Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador; Biología, Colegio de Ciencias Biológicas y Ambientales COCIBA, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - José Peña-Cisneros
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador
| | - Abigail Benavides-Almeida
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador
| | - Álvaro A Pérez-Meza
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador
| | - Alissen Haro-Vinueza
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador; Biología, Colegio de Ciencias Biológicas y Ambientales COCIBA, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Cristina Ruiz
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador
| | | | - Doménica Tenesaca
- Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador
| | - Diego Barba
- Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador
| | - Kevin Zambrano
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Escuela de Medicina, Quito, Ecuador; Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador; School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, the Netherlands; Instituto de Neurociencias, Universidad San Francisco de Quito USFQ, Quito, Ecuador
| | - Verónica Castañeda
- Universidad San Francisco de Quito USFQ, Instituto de Investigaciones en Biomedicina iBioMed, Quito, Ecuador; Mito-Act Research Consortium, Quito, Ecuador; Biología, Colegio de Ciencias Biológicas y Ambientales COCIBA, Universidad San Francisco de Quito USFQ, Quito, Ecuador; PhD Program in Biomedicine, Faculty of Medicine, Universidad de los Andes, Santiago, Chile
| | - Keshav K Singh
- Departments of Genetics, Dermatology and Pathology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
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5
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LaPeruta AJ, Micic J, Woolford Jr. JL. Additional principles that govern the release of pre-ribosomes from the nucleolus into the nucleoplasm in yeast. Nucleic Acids Res 2023; 51:10867-10883. [PMID: 35736211 PMCID: PMC10639060 DOI: 10.1093/nar/gkac430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 05/05/2022] [Accepted: 06/20/2022] [Indexed: 11/14/2022] Open
Abstract
During eukaryotic ribosome biogenesis, pre-ribosomes travel from the nucleolus, where assembly is initiated, to the nucleoplasm and then are exported to the cytoplasm, where assembly concludes. Although nuclear export of pre-ribosomes has been extensively investigated, the release of pre-ribosomes from the nucleolus is an understudied phenomenon. Initial data indicate that unfolded rRNA interacts in trans with nucleolar components and that, when rRNA folds due to ribosomal protein (RP) binding, the number of trans interactions drops below the threshold necessary for nucleolar retention. To validate and expand on this idea, we performed a bioinformatic analysis of the protein components of the Saccharomyces cerevisiae ribosome assembly pathway. We found that ribosome biogenesis factors (RiBi factors) contain significantly more predicted trans interacting regions than RPs. We also analyzed cryo-EM structures of ribosome assembly intermediates to determine how nucleolar pre-ribosomes differ from post-nucleolar pre-ribosomes, specifically the capacity of RPs, RiBi factors, and rRNA components to interact in trans. We observed a significant decrease in the theoretical trans-interacting capability of pre-ribosomes between nucleolar and post-nucleolar stages of assembly due to the release of RiBi factors from particles and the folding of rRNA. Here, we provide a mechanism for the release of pre-ribosomes from the nucleolus.
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Affiliation(s)
- Amber J LaPeruta
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Jelena Micic
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - John L Woolford Jr.
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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6
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Potter A, Cabrera-Orefice A, Spelbrink JN. Let's make it clear: systematic exploration of mitochondrial DNA- and RNA-protein complexes by complexome profiling. Nucleic Acids Res 2023; 51:10619-10641. [PMID: 37615582 PMCID: PMC10602928 DOI: 10.1093/nar/gkad697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 07/18/2023] [Accepted: 08/11/2023] [Indexed: 08/25/2023] Open
Abstract
Complexome profiling (CP) is a powerful tool for systematic investigation of protein interactors that has been primarily applied to study the composition and dynamics of mitochondrial protein complexes. Here, we further optimized this method to extend its application to survey mitochondrial DNA- and RNA-interacting protein complexes. We established that high-resolution clear native gel electrophoresis (hrCNE) is a better alternative to preserve DNA- and RNA-protein interactions that are otherwise disrupted when samples are separated by the widely used blue native gel electrophoresis (BNE). In combination with enzymatic digestion of DNA, our CP approach improved the identification of a wide range of protein interactors of the mitochondrial gene expression system without compromising the detection of other multiprotein complexes. The utility of this approach was particularly demonstrated by analysing the complexome changes in human mitochondria with impaired gene expression after transient, chemically induced mitochondrial DNA depletion. Effects of RNase on mitochondrial protein complexes were also evaluated and discussed. Overall, our adaptations significantly improved the identification of mitochondrial DNA- and RNA-protein interactions by CP, thereby unlocking the comprehensive analysis of a near-complete mitochondrial complexome in a single experiment.
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Affiliation(s)
- Alisa Potter
- Department of Pediatrics, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands
- Radboud Center for Mitochondrial Medicine (RCMM), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Alfredo Cabrera-Orefice
- Radboud Center for Mitochondrial Medicine (RCMM), Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Medical BioSciences, Radboud University Medical Center, Nijmegen, The Netherlands
- Functional Proteomics, Institute for Cardiovascular Physiology, Goethe University, Frankfurt am Main, Germany
| | - Johannes N Spelbrink
- Department of Pediatrics, Amalia Children's Hospital, Radboud University Medical Center, Nijmegen, The Netherlands
- Radboud Center for Mitochondrial Medicine (RCMM), Radboud University Medical Center, Nijmegen, The Netherlands
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7
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Ma J, Sun L, Gao W, Li Y, Dong D. RNA binding protein: coordinated expression between the nuclear and mitochondrial genomes in tumors. J Transl Med 2023; 21:512. [PMID: 37507746 PMCID: PMC10386658 DOI: 10.1186/s12967-023-04373-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Mitochondria are the only organelles regulated by two genomes. The coordinated translation of nuclear DNA (nDNA) and mitochondrial DNA (mtDNA), which together co-encode the subunits of the oxidative phosphorylation (OXPHOS) complex, is critical for determining the metabolic plasticity of tumor cells. RNA-binding protein (RBP) is a post-transcriptional regulatory factor that plays a pivotal role in determining the fate of mRNA. RBP rapidly and effectively reshapes the mitochondrial proteome in response to intracellular and extracellular stressors, mediating the cytoplasmic and mitochondrial translation balance to adjust mitochondrial respiratory capacity and provide energy for tumor cells to adapt to different environmental pressures and growth needs. This review highlights the ability of RBPs to use liquid-liquid phase separation (LLPS) as a platform for translation regulation, integrating nuclear-mitochondrial positive and retrograde signals to coordinate cross-department translation, reshape mitochondrial energy metabolism, and promote the development and survival of tumor cells.
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Affiliation(s)
- Jiaoyan Ma
- Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China
| | - Liankun Sun
- Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China
| | - Weinan Gao
- Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China
| | - Yang Li
- Department of Physiology, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China
| | - Delu Dong
- Department of Pathophysiology, College of Basic Medical Sciences, Jilin University, Changchun, 130021, China.
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8
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Khawaja A, Cipullo M, Krüger A, Rorbach J. Insights into mitoribosomal biogenesis from recent structural studies. Trends Biochem Sci 2023; 48:629-641. [PMID: 37169615 DOI: 10.1016/j.tibs.2023.04.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 05/13/2023]
Abstract
The mitochondrial ribosome (mitoribosome) is a multicomponent machine that has unique structural features. Biogenesis of the human mitoribosome includes correct maturation and folding of the mitochondria-encoded RNA components (12S and 16S mt-rRNAs, and mt-tRNAVal) and their assembly together with 82 nucleus-encoded mitoribosomal proteins. This complex process requires the coordinated action of multiple assembly factors. Recent advances in single-particle cryo-electron microscopy (cryo-EM) have provided detailed insights into the specific functions of several mitoribosome assembly factors and have defined their timing. In this review we summarize mitoribosomal small (mtSSU) and large subunit (mtLSU) biogenesis based on structural findings, and we discuss potential crosstalk between mtSSU and mtLSU assembly pathways as well as coordination between mitoribosome biogenesis and other processes involved in mitochondrial gene expression.
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Affiliation(s)
- Anas Khawaja
- Department of Medical Biochemistry and Biophysics, Division of Molecular Metabolism, Karolinska Institutet, Biomedicum, 171 65 Solna, Sweden; Max Planck Institute Biology of Ageing, Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Miriam Cipullo
- Department of Medical Biochemistry and Biophysics, Division of Molecular Metabolism, Karolinska Institutet, Biomedicum, 171 65 Solna, Sweden; Max Planck Institute Biology of Ageing, Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Annika Krüger
- Department of Medical Biochemistry and Biophysics, Division of Molecular Metabolism, Karolinska Institutet, Biomedicum, 171 65 Solna, Sweden; Max Planck Institute Biology of Ageing, Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Joanna Rorbach
- Department of Medical Biochemistry and Biophysics, Division of Molecular Metabolism, Karolinska Institutet, Biomedicum, 171 65 Solna, Sweden; Max Planck Institute Biology of Ageing, Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.
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9
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Fei L, Lu Z, Xu Y, Hou G. A comprehensive pan-cancer analysis of the expression characteristics, prognostic value, and immune characteristics of TOP1MT. Front Genet 2022; 13:920897. [PMID: 36035140 PMCID: PMC9399363 DOI: 10.3389/fgene.2022.920897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 07/12/2022] [Indexed: 12/01/2022] Open
Abstract
Background: Mitochondria are at the heart of a number of metabolic pathways providing enormous energy for normal cell growth and regulating tumor cell growth as well as survival. Mitochondrial topoisomerase I (TOP1MT) is a type IB topoisomerase found in the mitochondria of vertebrates. However, no pan-cancer analysis of TOP1MT has been reported. This study aims to explore TOP1MT expression in pan-cancer tissues and identify whether it can be a target for mitochondrial anticancer therapy. Methods and results: The original TOP1MT expression data in 33 different types of cancer patients were downloaded from the TCGA and GTEx databases. TOP1MT was highly expressed in cancer tissues, including BLCA, BRCA, CHOL, COAD, DLBC, ESCA, GBM, HNSC, KIRC, KIRP, LGG, LIHC, LUAD, LUSC, PAAD, PCPG, PRAD, READ, SKCM, STAD, THYM, UCEC, and UCS. According to Kaplan-Meier survival curve analysis, high TOP1MT expression in BLCA, HNSC, KIRP, PAAD, UCEC, and LIHC cancer tissues was linked to poor prognosis of cancer patients, i.e., poor OS, disease-specific survival, and PFI. Linkedomics analysis identified a positive correlation of TOP1MT expression with CNA, but a negative correlation with methylation. TOP1MT expression significantly correlated with immune cells and immune checkpoints in the TIMER database. Functional analysis showed a close relationship between TOP1MT expression and ribosomes. Conclusion: In summary, TOP1MT is a potential biomarker for mitochondrial anticancer therapy and cancer immunotherapy.
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Affiliation(s)
- Lihong Fei
- Department of Gastroenterology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Zhimin Lu
- Department of Outpatient, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
| | - Yufen Xu
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
- *Correspondence: Yufen Xu, ; Guoxin Hou,
| | - Guoxin Hou
- Department of Oncology, The First Hospital of Jiaxing, Affiliated Hospital of Jiaxing University, Jiaxing, Zhejiang, China
- *Correspondence: Yufen Xu, ; Guoxin Hou,
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10
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Ziemann M, Wu W, Deng XL, Du XJ. Transcriptomic Analysis of Dysregulated Genes of the nDNA-mtDNA Axis in a Mouse Model of Dilated Cardiomyopathy. Front Genet 2022; 13:921610. [PMID: 35754828 PMCID: PMC9214240 DOI: 10.3389/fgene.2022.921610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/17/2022] [Indexed: 11/30/2022] Open
Abstract
Background: Mitochondrial dysfunction is implicated in the development of cardiomyopathy and heart failure. Transcription of mitochondrial DNA (mtDNA) encoded genes and subsequent protein synthesis are tightly regulated by nuclear DNA (nDNA) encoded proteins forming the nDNA-mtDNA axis. The scale of abnormalities in this axis in dilated cardiomyopathy (DCM) is unclear. We previously demonstrated, in a mouse DCM model with cardiac Mst1 overexpression, extensive downregulation of mitochondrial genes and mitochondrial dysfunction. Using the pre-acquired transcriptome sequencing database, we studied expression of gene sets of the nDNA-mtDNA axis. Methods: Using RNA-sequencing data from DCM hearts of mice at early and severe disease stages, transcriptome was performed for dysregulated nDNA-encoded gene sets that govern mtDNA transcription and in situ protein synthesis. To validate gene data, expression of a panel of proteins was determined by immunoblotting. Results: Relative to littermate controls, DCM hearts showed significant downregulation of all mtDNA encoded mRNAs, as well as mtDNA transcriptional activators. Downregulation was also evident for gene sets of mt-rRNA processing, aminoacyl-tRNA synthases, and mitoribosome subunits for in situ protein synthesis. Multiple downregulated genes belong to mitochondrial protein-importing machinery indicating compromised importing of proteins for mtDNA transcription and translation. Diverse changes were genes of mtRNA-binding proteins that govern maturation and stability of mtDNA-derived RNAs. Expression of mtDNA replicome genes was largely unchanged. These changes were similarly observed in mouse hearts at early and severe stages of DCM. Conclusion: Transcriptome revealed in our DCM model dysregulation of multiple gene sets of the nDNA-mtDNA axis, that is, expected to interfere with mtDNA transcription and in situ protein synthesis. Dysfunction of the nDNA-mtDNA axis might contribute to mitochondrial dysfunction and ultimately development of DCM.
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Affiliation(s)
- Mark Ziemann
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, Australia
| | - Wei Wu
- Key Laboratory of Environment and Genes Related to Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Ministry of Education, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xiu-Ling Deng
- Key Laboratory of Environment and Genes Related to Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Ministry of Education, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xiao-Jun Du
- Key Laboratory of Environment and Genes Related to Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Ministry of Education, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
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11
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Organization and expression of the mammalian mitochondrial genome. Nat Rev Genet 2022; 23:606-623. [PMID: 35459860 DOI: 10.1038/s41576-022-00480-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/21/2022] [Indexed: 02/07/2023]
Abstract
The mitochondrial genome encodes core subunits of the respiratory chain that drives oxidative phosphorylation and is, therefore, essential for energy conversion. Advances in high-throughput sequencing technologies and cryoelectron microscopy have shed light on the structure and organization of the mitochondrial genome and revealed unique mechanisms of mitochondrial gene regulation. New animal models of impaired mitochondrial protein synthesis have shown how the coordinated regulation of the cytoplasmic and mitochondrial translation machineries ensures the correct assembly of the respiratory chain complexes. These new technologies and disease models are providing a deeper understanding of mitochondrial genome organization and expression and of the diseases caused by impaired energy conversion, including mitochondrial, neurodegenerative, cardiovascular and metabolic diseases. They also provide avenues for the development of treatments for these conditions.
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12
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Miranda M, Bonekamp NA, Kühl I. Starting the engine of the powerhouse: mitochondrial transcription and beyond. Biol Chem 2022; 403:779-805. [PMID: 35355496 DOI: 10.1515/hsz-2021-0416] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 03/09/2022] [Indexed: 12/25/2022]
Abstract
Mitochondria are central hubs for cellular metabolism, coordinating a variety of metabolic reactions crucial for human health. Mitochondria provide most of the cellular energy via their oxidative phosphorylation (OXPHOS) system, which requires the coordinated expression of genes encoded by both the nuclear (nDNA) and mitochondrial genomes (mtDNA). Transcription of mtDNA is not only essential for the biogenesis of the OXPHOS system, but also generates RNA primers necessary to initiate mtDNA replication. Like the prokaryotic system, mitochondria have no membrane-based compartmentalization to separate the different steps of mtDNA maintenance and expression and depend entirely on nDNA-encoded factors imported into the organelle. Our understanding of mitochondrial transcription in mammalian cells has largely progressed, but the mechanisms regulating mtDNA gene expression are still poorly understood despite their profound importance for human disease. Here, we review mechanisms of mitochondrial gene expression with a focus on the recent findings in the field of mammalian mtDNA transcription and disease phenotypes caused by defects in proteins involved in this process.
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Affiliation(s)
- Maria Miranda
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, D-50931, Germany
| | - Nina A Bonekamp
- Department of Neuroanatomy, Mannheim Center for Translational Neurosciences (MCTN), Medical Faculty Mannheim, Heidelberg University, Mannheim, D-68167, Germany
| | - Inge Kühl
- Department of Cell Biology, Institute of Integrative Biology of the Cell (I2BC), UMR9198, CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, F-91190, France
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13
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Rebelo-Guiomar P, Pellegrino S, Dent KC, Sas-Chen A, Miller-Fleming L, Garone C, Van Haute L, Rogan JF, Dinan A, Firth AE, Andrews B, Whitworth AJ, Schwartz S, Warren AJ, Minczuk M. A late-stage assembly checkpoint of the human mitochondrial ribosome large subunit. Nat Commun 2022; 13:929. [PMID: 35177605 PMCID: PMC8854578 DOI: 10.1038/s41467-022-28503-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 01/20/2022] [Indexed: 12/04/2022] Open
Abstract
Many cellular processes, including ribosome biogenesis, are regulated through post-transcriptional RNA modifications. Here, a genome-wide analysis of the human mitochondrial transcriptome shows that 2’-O-methylation is limited to residues of the mitoribosomal large subunit (mtLSU) 16S mt-rRNA, introduced by MRM1, MRM2 and MRM3, with the modifications installed by the latter two proteins being interdependent. MRM2 controls mitochondrial respiration by regulating mitoribosome biogenesis. In its absence, mtLSU particles (visualized by cryo-EM at the resolution of 2.6 Å) present disordered RNA domains, partial occupancy of bL36m and bound MALSU1:L0R8F8:mtACP anti-association module, allowing five mtLSU biogenesis intermediates with different intersubunit interface configurations to be placed along the assembly pathway. However, mitoribosome biogenesis does not depend on the methyltransferase activity of MRM2. Disruption of the MRM2 Drosophila melanogaster orthologue leads to mitochondria-related developmental arrest. This work identifies a key checkpoint during mtLSU assembly, essential to maintain mitochondrial homeostasis. Rebelo-Guiomar et al. unveil late stage assembly intermediates of the human mitochondrial ribosome by inactivating the methyltransferase MRM2 in cells. Absence of MRM2 impairs organismal homeostasis, while its catalytic activity is dispensable for mitoribosomal biogenesis.
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Affiliation(s)
- Pedro Rebelo-Guiomar
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK
| | - Simone Pellegrino
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust - MRC Stem Cell Institute, Cambridge Biomedical Campus, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, CB2 0AW, UK.,Department of Haematology, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, CB2 0AW, UK
| | - Kyle C Dent
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust - MRC Stem Cell Institute, Cambridge Biomedical Campus, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, CB2 0AW, UK.,Department of Haematology, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, CB2 0AW, UK.,MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Aldema Sas-Chen
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 76100, Israel.,Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Leonor Miller-Fleming
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK
| | - Caterina Garone
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, 40137, Italy
| | - Lindsey Van Haute
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK
| | - Jack F Rogan
- STORM Therapeutics Limited, Babraham Research Campus, Moneta Building, Cambridge, CB22 3AT, UK
| | - Adam Dinan
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Andrew E Firth
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Byron Andrews
- STORM Therapeutics Limited, Babraham Research Campus, Moneta Building, Cambridge, CB22 3AT, UK
| | - Alexander J Whitworth
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK
| | - Schraga Schwartz
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Alan J Warren
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust - MRC Stem Cell Institute, Cambridge Biomedical Campus, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, CB2 0AW, UK.,Department of Haematology, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, CB2 0AW, UK
| | - Michal Minczuk
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.
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14
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Lenarčič T, Niemann M, Ramrath DJF, Calderaro S, Flügel T, Saurer M, Leibundgut M, Boehringer D, Prange C, Horn EK, Schneider A, Ban N. Mitoribosomal small subunit maturation involves formation of initiation-like complexes. Proc Natl Acad Sci U S A 2022; 119:e2114710118. [PMID: 35042777 PMCID: PMC8784144 DOI: 10.1073/pnas.2114710118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 10/29/2021] [Indexed: 01/02/2023] Open
Abstract
Mitochondrial ribosomes (mitoribosomes) play a central role in synthesizing mitochondrial inner membrane proteins responsible for oxidative phosphorylation. Although mitoribosomes from different organisms exhibit considerable structural variations, recent insights into mitoribosome assembly suggest that mitoribosome maturation follows common principles and involves a number of conserved assembly factors. To investigate the steps involved in the assembly of the mitoribosomal small subunit (mt-SSU) we determined the cryoelectron microscopy structures of middle and late assembly intermediates of the Trypanosoma brucei mitochondrial small subunit (mt-SSU) at 3.6- and 3.7-Å resolution, respectively. We identified five additional assembly factors that together with the mitochondrial initiation factor 2 (mt-IF-2) specifically interact with functionally important regions of the rRNA, including the decoding center, thereby preventing premature mRNA or large subunit binding. Structural comparison of assembly intermediates with mature mt-SSU combined with RNAi experiments suggests a noncanonical role of mt-IF-2 and a stepwise assembly process, where modular exchange of ribosomal proteins and assembly factors together with mt-IF-2 ensure proper 9S rRNA folding and protein maturation during the final steps of assembly.
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Affiliation(s)
- Tea Lenarčič
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Moritz Niemann
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - David J F Ramrath
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Salvatore Calderaro
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - Timo Flügel
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Martin Saurer
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Marc Leibundgut
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Daniel Boehringer
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Céline Prange
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Elke K Horn
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - André Schneider
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, CH-3012 Bern, Switzerland
| | - Nenad Ban
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland;
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15
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Criscuolo D, Avolio R, Matassa DS, Esposito F. Targeting Mitochondrial Protein Expression as a Future Approach for Cancer Therapy. Front Oncol 2021; 11:797265. [PMID: 34888254 PMCID: PMC8650000 DOI: 10.3389/fonc.2021.797265] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 11/03/2021] [Indexed: 12/20/2022] Open
Abstract
Extensive metabolic remodeling is a fundamental feature of cancer cells. Although early reports attributed such remodeling to a loss of mitochondrial functions, it is now clear that mitochondria play central roles in cancer development and progression, from energy production to synthesis of macromolecules, from redox modulation to regulation of cell death. Biosynthetic pathways are also heavily affected by the metabolic rewiring, with protein synthesis dysregulation at the hearth of cellular transformation. Accumulating evidence in multiple organisms shows that the metabolic functions of mitochondria are tightly connected to protein synthesis, being assembly and activity of respiratory complexes highly dependent on de novo synthesis of their components. In turn, protein synthesis within the organelle is tightly connected with the cytosolic process. This implies an entire network of interactions and fine-tuned regulations that build up a completely under-estimated level of complexity. We are now only preliminarily beginning to reconstitute such regulatory level in human cells, and to perceive its role in diseases. Indeed, disruption or alterations of these connections trigger conditions of proteotoxic and energetic stress that could be potentially exploited for therapeutic purposes. In this review, we summarize the available literature on the coordinated regulation of mitochondrial and cytosolic mRNA translation, and their effects on the integrity of the mitochondrial proteome and functions. Finally, we highlight the potential held by this topic for future research directions and for the development of innovative therapeutic approaches.
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Affiliation(s)
- Daniela Criscuolo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy
| | - Rosario Avolio
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy
| | - Danilo Swann Matassa
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy
| | - Franca Esposito
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy
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16
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Kim M, Schulz V, Brings L, Schoeller T, Kühn K, Vierling E. mTERF18 and ATAD3 are required for mitochondrial nucleoid structure and their disruption confers heat tolerance in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2021; 232:2026-2042. [PMID: 34482561 DOI: 10.1111/nph.17717] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/23/2021] [Indexed: 05/27/2023]
Abstract
Mitochondria play critical roles in generating ATP through oxidative phosphorylation (OXPHOS) and produce both damaging and signaling reactive oxygen species (ROS). They have reduced genomes that encode essential subunits of the OXPHOS machinery. Mitochondrial Transcription tERmination Factor-related (mTERF) proteins are involved in organelle gene expression, interacting with organellar DNA or RNA. We previously found that mutations in Arabidopsis thaliana mTERF18/SHOT1 enable plants to better tolerate heat and oxidative stresses, presumably due to low ROS production and reduced oxidative damage. Here we discover that shot1 mutants have greatly reduced OXPHOS complexes I and IV and reveal that suppressor of hot1-4 1 (SHOT1) binds DNA and localizes to mitochondrial nucleoids, which are disrupted in shot1. Furthermore, three homologues of animal ATPase family AAA domain-containing protein 3 (ATAD3), which is involved in mitochondrial nucleoid organization, were identified as SHOT1-interacting proteins. Importantly, disrupting ATAD3 function disrupts nucleoids, reduces accumulation of complex I, and enhances heat tolerance, as is seen in shot1 mutants. Our data link nucleoid organization to OXPHOS biogenesis and suggest that the common defects in shot1 mutants and ATAD3-disrupted plants lead to critical changes in mitochondrial metabolism and signaling that result in plant heat tolerance.
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Affiliation(s)
- Minsoo Kim
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA, 01003, USA
| | - Vincent Schulz
- Department of Life Sciences, Institute of Biology, Humboldt-Universität zu Berlin, 10099, Berlin, Germany
| | - Lea Brings
- Department of Life Sciences, Institute of Biology, Humboldt-Universität zu Berlin, 10099, Berlin, Germany
| | - Theresa Schoeller
- Department of Plant Physiology, Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Kristina Kühn
- Department of Life Sciences, Institute of Biology, Humboldt-Universität zu Berlin, 10099, Berlin, Germany
- Department of Plant Physiology, Institute of Biology, Martin-Luther-Universität Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Elizabeth Vierling
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA, 01003, USA
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17
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Xavier VJ, Martinou JC. RNA Granules in the Mitochondria and Their Organization under Mitochondrial Stresses. Int J Mol Sci 2021; 22:9502. [PMID: 34502411 PMCID: PMC8431320 DOI: 10.3390/ijms22179502] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 08/25/2021] [Accepted: 08/27/2021] [Indexed: 12/25/2022] Open
Abstract
The human mitochondrial genome (mtDNA) regulates its transcription products in specialised and distinct ways as compared to nuclear transcription. Thanks to its mtDNA mitochondria possess their own set of tRNAs, rRNAs and mRNAs that encode a subset of the protein subunits of the electron transport chain complexes. The RNA regulation within mitochondria is organised within specialised, membraneless, compartments of RNA-protein complexes, called the Mitochondrial RNA Granules (MRGs). MRGs were first identified to contain nascent mRNA, complexed with many proteins involved in RNA processing and maturation and ribosome assembly. Most recently, double-stranded RNA (dsRNA) species, a hybrid of the two complementary mRNA strands, were found to form granules in the matrix of mitochondria. These RNA granules are therefore components of the mitochondrial post-transcriptional pathway and as such play an essential role in mitochondrial gene expression. Mitochondrial dysfunctions in the form of, for example, RNA processing or RNA quality control defects, or inhibition of mitochondrial fission, can cause the loss or the aberrant accumulation of these RNA granules. These findings underline the important link between mitochondrial maintenance and the efficient expression of its genome.
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Affiliation(s)
| | - Jean-Claude Martinou
- Department of Cell Biology, Faculty of Sciences, University of Geneva, 1205 Geneva, Switzerland;
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18
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Hilander T, Jackson CB, Robciuc M, Bashir T, Zhao H. The roles of assembly factors in mammalian mitoribosome biogenesis. Mitochondrion 2021; 60:70-84. [PMID: 34339868 DOI: 10.1016/j.mito.2021.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 02/08/2023]
Abstract
As ancient bacterial endosymbionts of eukaryotic cells, mitochondria have retained their own circular DNA as well as protein translation system including mitochondrial ribosomes (mitoribosomes). In recent years, methodological advancements in cryoelectron microscopy and mass spectrometry have revealed the extent of the evolutionary divergence of mitoribosomes from their bacterial ancestors and their adaptation to the synthesis of 13 mitochondrial DNA encoded oxidative phosphorylation complex subunits. In addition to the structural data, the first assembly pathway maps of mitoribosomes have started to emerge and concomitantly also the assembly factors involved in this process to achieve fully translational competent particles. These transiently associated factors assist in the intricate assembly process of mitoribosomes by enhancing protein incorporation, ribosomal RNA folding and modification, and by blocking premature or non-native protein binding, for example. This review focuses on summarizing the current understanding of the known mammalian mitoribosome assembly factors and discussing their possible roles in the assembly of small or large mitoribosomal subunits.
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Affiliation(s)
- Taru Hilander
- Faculty of Biological and Environmental Sciences, University of Helsinki, Finland.
| | - Christopher B Jackson
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Finland.
| | - Marius Robciuc
- Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
| | - Tanzeela Bashir
- Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
| | - Hongxia Zhao
- Faculty of Biological and Environmental Sciences, University of Helsinki, Finland; Key Laboratory of Stem Cell and Biopharmaceutical Technology, School of Life Sciences, Guangxi Normal University, Guangxi, China.
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19
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D’Souza AR, Van Haute L, Powell CA, Mutti CD, Páleníková P, Rebelo-Guiomar P, Rorbach J, Minczuk M. YbeY is required for ribosome small subunit assembly and tRNA processing in human mitochondria. Nucleic Acids Res 2021; 49:5798-5812. [PMID: 34037799 PMCID: PMC8191802 DOI: 10.1093/nar/gkab404] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/20/2021] [Accepted: 05/06/2021] [Indexed: 12/12/2022] Open
Abstract
Mitochondria contain their own translation apparatus which enables them to produce the polypeptides encoded in their genome. The mitochondrially-encoded RNA components of the mitochondrial ribosome require various post-transcriptional processing steps. Additional protein factors are required to facilitate the biogenesis of the functional mitoribosome. We have characterized a mitochondrially-localized protein, YbeY, which interacts with the assembling mitoribosome through the small subunit. Loss of YbeY leads to a severe reduction in mitochondrial translation and a loss of cell viability, associated with less accurate mitochondrial tRNASer(AGY) processing from the primary transcript and a defect in the maturation of the mitoribosomal small subunit. Our results suggest that YbeY performs a dual, likely independent, function in mitochondria being involved in precursor RNA processing and mitoribosome biogenesis. Issue Section: Nucleic Acid Enzymes.
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Affiliation(s)
- Aaron R D’Souza
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Lindsey Van Haute
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Christopher A Powell
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Christian D Mutti
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Petra Páleníková
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Pedro Rebelo-Guiomar
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Joanna Rorbach
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Michal Minczuk
- To whom correspondence should be addressed. Tel: +44 122 325 2750;
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20
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High-resolution imaging reveals compartmentalization of mitochondrial protein synthesis in cultured human cells. Proc Natl Acad Sci U S A 2021; 118:2008778118. [PMID: 33526660 PMCID: PMC8017971 DOI: 10.1073/pnas.2008778118] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In mitochondria from various species, the OXPHOS complexes reside mainly in the invaginated cristae membranes, as opposed to the inner boundary membrane (IBM) that parallels the mitochondrial outer membrane. However, the IBM contains dynamic contact sites enriched for translocases that import proteins from the cytosol. As the majority of OXPHOS components are imported and need to be integrated in assembly with the mtDNA-encoded components, where does intramitochondrial translation occur? Here we report: 1) a method for visualizing protein synthesis in human mitochondria at super resolution; 2) that synthesis is enriched at cristae membranes, in preference to the IBM; and 3) that sites of translation are spatially separated from RNA granules where RNA processing, maturation, and mitoribosomal assembly occur. Human mitochondria contain their own genome, mitochondrial DNA, that is expressed in the mitochondrial matrix. This genome encodes 13 vital polypeptides that are components of the multisubunit complexes that couple oxidative phosphorylation (OXPHOS). The inner mitochondrial membrane that houses these complexes comprises the inner boundary membrane that runs parallel to the outer membrane, infoldings that form the cristae membranes, and the cristae junctions that separate the two. It is in these cristae membranes that the OXPHOS complexes have been shown to reside in various species. The majority of the OXPHOS subunits are nuclear-encoded and must therefore be imported from the cytosol through the outer membrane at contact sites with the inner boundary membrane. As the mitochondrially encoded components are also integral members of these complexes, where does protein synthesis occur? As transcription, mRNA processing, maturation, and at least part of the mitoribosome assembly process occur at the nucleoid and the spatially juxtaposed mitochondrial RNA granules, is protein synthesis also performed at the RNA granules close to these entities, or does it occur distal to these sites? We have adapted a click chemistry-based method coupled with stimulated emission depletion nanoscopy to address these questions. We report that, in human cells in culture, within the limits of our methodology, the majority of mitochondrial protein synthesis is detected at the cristae membranes and is spatially separated from the sites of RNA processing and maturation.
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21
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Human Mitoribosome Biogenesis and Its Emerging Links to Disease. Int J Mol Sci 2021; 22:ijms22083827. [PMID: 33917098 PMCID: PMC8067846 DOI: 10.3390/ijms22083827] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/23/2021] [Accepted: 03/24/2021] [Indexed: 12/20/2022] Open
Abstract
Mammalian mitochondrial ribosomes (mitoribosomes) synthesize a small subset of proteins, which are essential components of the oxidative phosphorylation machinery. Therefore, their function is of fundamental importance to cellular metabolism. The assembly of mitoribosomes is a complex process that progresses through numerous maturation and protein-binding events coordinated by the actions of several assembly factors. Dysregulation of mitoribosome production is increasingly recognized as a contributor to metabolic and neurodegenerative diseases. In recent years, mutations in multiple components of the mitoribosome assembly machinery have been associated with a range of human pathologies, highlighting their importance to cell function and health. Here, we provide a review of our current understanding of mitoribosome biogenesis, highlighting the key factors involved in this process and the growing number of mutations in genes encoding mitoribosomal RNAs, proteins, and assembly factors that lead to human disease.
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22
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Blackout in the powerhouse: clinical phenotypes associated with defects in the assembly of OXPHOS complexes and the mitoribosome. Biochem J 2021; 477:4085-4132. [PMID: 33151299 PMCID: PMC7657662 DOI: 10.1042/bcj20190767] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/29/2020] [Accepted: 10/05/2020] [Indexed: 12/26/2022]
Abstract
Mitochondria produce the bulk of the energy used by almost all eukaryotic cells through oxidative phosphorylation (OXPHOS) which occurs on the four complexes of the respiratory chain and the F1–F0 ATPase. Mitochondrial diseases are a heterogenous group of conditions affecting OXPHOS, either directly through mutation of genes encoding subunits of OXPHOS complexes, or indirectly through mutations in genes encoding proteins supporting this process. These include proteins that promote assembly of the OXPHOS complexes, the post-translational modification of subunits, insertion of cofactors or indeed subunit synthesis. The latter is important for all 13 of the proteins encoded by human mitochondrial DNA, which are synthesised on mitochondrial ribosomes. Together the five OXPHOS complexes and the mitochondrial ribosome are comprised of more than 160 subunits and many more proteins support their biogenesis. Mutations in both nuclear and mitochondrial genes encoding these proteins have been reported to cause mitochondrial disease, many leading to defective complex assembly with the severity of the assembly defect reflecting the severity of the disease. This review aims to act as an interface between the clinical and basic research underpinning our knowledge of OXPHOS complex and ribosome assembly, and the dysfunction of this process in mitochondrial disease.
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23
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Mechanisms and regulation of protein synthesis in mitochondria. Nat Rev Mol Cell Biol 2021; 22:307-325. [PMID: 33594280 DOI: 10.1038/s41580-021-00332-2] [Citation(s) in RCA: 154] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2021] [Indexed: 02/06/2023]
Abstract
Mitochondria are cellular organelles responsible for generation of chemical energy in the process called oxidative phosphorylation. They originate from a bacterial ancestor and maintain their own genome, which is expressed by designated, mitochondrial transcription and translation machineries that differ from those operating for nuclear gene expression. In particular, the mitochondrial protein synthesis machinery is structurally and functionally very different from that governing eukaryotic, cytosolic translation. Despite harbouring their own genetic information, mitochondria are far from being independent of the rest of the cell and, conversely, cellular fitness is closely linked to mitochondrial function. Mitochondria depend heavily on the import of nuclear-encoded proteins for gene expression and function, and hence engage in extensive inter-compartmental crosstalk to regulate their proteome. This connectivity allows mitochondria to adapt to changes in cellular conditions and also mediates responses to stress and mitochondrial dysfunction. With a focus on mammals and yeast, we review fundamental insights that have been made into the biogenesis, architecture and mechanisms of the mitochondrial translation apparatus in the past years owing to the emergence of numerous near-atomic structures and a considerable amount of biochemical work. Moreover, we discuss how cellular mitochondrial protein expression is regulated, including aspects of mRNA and tRNA maturation and stability, roles of auxiliary factors, such as translation regulators, that adapt mitochondrial translation rates, and the importance of inter-compartmental crosstalk with nuclear gene expression and cytosolic translation and how it enables integration of mitochondrial translation into the cellular context.
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24
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Tobiasson V, Gahura O, Aibara S, Baradaran R, Zíková A, Amunts A. Interconnected assembly factors regulate the biogenesis of mitoribosomal large subunit. EMBO J 2021; 40:e106292. [PMID: 33576519 PMCID: PMC7957421 DOI: 10.15252/embj.2020106292] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 12/18/2020] [Accepted: 12/23/2020] [Indexed: 12/11/2022] Open
Abstract
Mitoribosomes consist of ribosomal RNA and protein components, coordinated assembly of which is critical for function. We used mitoribosomes from Trypanosoma brucei with reduced RNA and increased protein mass to provide insights into the biogenesis of the mitoribosomal large subunit. Structural characterization of a stable assembly intermediate revealed 22 assembly factors, some of which have orthologues/counterparts/homologues in mammalian genomes. These assembly factors form a protein network that spans a distance of 180 Å, shielding the ribosomal RNA surface. The central protuberance and L7/L12 stalk are not assembled entirely and require removal of assembly factors and remodeling of the mitoribosomal proteins to become functional. The conserved proteins GTPBP7 and mt‐EngA are bound together at the subunit interface in proximity to the peptidyl transferase center. A mitochondrial acyl‐carrier protein plays a role in docking the L1 stalk, which needs to be repositioned during maturation. Additional enzymatically deactivated factors scaffold the assembly while the exit tunnel is blocked. Together, this extensive network of accessory factors stabilizes the immature sites and connects the functionally important regions of the mitoribosomal large subunit.
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Affiliation(s)
- Victor Tobiasson
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden
| | - Ondřej Gahura
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Shintaro Aibara
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden
| | - Rozbeh Baradaran
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden
| | - Alena Zíková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Alexey Amunts
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden
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25
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Role of GTPases in Driving Mitoribosome Assembly. Trends Cell Biol 2021; 31:284-297. [PMID: 33419649 DOI: 10.1016/j.tcb.2020.12.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 12/01/2020] [Accepted: 12/11/2020] [Indexed: 01/08/2023]
Abstract
Mitoribosomes catalyze essential protein synthesis within mitochondria. Mitoribosome biogenesis is assisted by an increasing number of assembly factors, among which guanosine triphosphate hydrolases (GTPases) are the most abundant class. Here, we review recent progress in our understanding of mitoribosome assembly GTPases. We describe their shared and specific features and mechanisms of action, compare them with their bacterial counterparts, and discuss their possible roles in the assembly of small or large mitoribosomal subunits and the formation of the monosome by establishing quality-control checkpoints during these processes. Furthermore, following the recent unification of the nomenclature for the mitoribosomal proteins, we also propose a unified nomenclature for mitoribosome assembly GTPases.
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26
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Abstract
Mitochondria contain ribosomes (mitoribosomes) specialized in the synthesis of a handful of proteins essential for oxidative phosphorylation. Therefore, mitoribosome integrity and function are essential for the life of eukaryotic cells and lesions that affect them result in devastating human disorders. To broadly analyze the integrity and assembly state of mitoribosomes it is useful to start by determining the sedimentation profile of these structures by sucrose gradient centrifugation of mitochondrial extracts. During centrifugation, mitoribosome subunits, monosomes and polysomes, and potentially accumulated assembly intermediates will sediment through the gradient at different rates. Sedimentation will depend on the centrifugal force applied and the density and viscosity of the gradient. Importantly, it will also depend on the size, shape, and density of the mitoribosome particles present in the samples under study. Variations of this technique, often coupled with additional downstream approaches, have been used to analyze the process of mitoribosome biogenesis, the composition of assembly intermediates, or to monitor the interaction of extraribosomal proteins with individual mitoribosome subunits or monosomes.
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Affiliation(s)
- Austin Choi
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Antoni Barrientos
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA.
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA.
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27
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Summer S, Smirnova A, Gabriele A, Toth U, Fasemore AM, Förstner KU, Kuhn L, Chicher J, Hammann P, Mitulović G, Entelis N, Tarassov I, Rossmanith W, Smirnov A. YBEY is an essential biogenesis factor for mitochondrial ribosomes. Nucleic Acids Res 2020; 48:9762-9786. [PMID: 32182356 PMCID: PMC7515705 DOI: 10.1093/nar/gkaa148] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 12/11/2022] Open
Abstract
Ribosome biogenesis requires numerous trans-acting factors, some of which are deeply conserved. In Bacteria, the endoribonuclease YbeY is believed to be involved in 16S rRNA 3′-end processing and its loss was associated with ribosomal abnormalities. In Eukarya, YBEY appears to generally localize to mitochondria (or chloroplasts). Here we show that the deletion of human YBEY results in a severe respiratory deficiency and morphologically abnormal mitochondria as an apparent consequence of impaired mitochondrial translation. Reduced stability of 12S rRNA and the deficiency of several proteins of the small ribosomal subunit in YBEY knockout cells pointed towards a defect in mitochondrial ribosome biogenesis. The specific interaction of mitoribosomal protein uS11m with YBEY suggests that the latter helps to properly incorporate uS11m into the nascent small subunit in its late assembly stage. This scenario shows similarities with final stages of cytosolic ribosome biogenesis, and may represent a late checkpoint before the mitoribosome engages in translation.
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Affiliation(s)
- Sabrina Summer
- Center for Anatomy & Cell Biology, Medical University of Vienna, Vienna A-1090, Austria
| | - Anna Smirnova
- UMR7156 - Molecular Genetics, Genomics, Microbiology, University of Strasbourg, CNRS, Strasbourg F-67000, France
| | - Alessandro Gabriele
- UMR7156 - Molecular Genetics, Genomics, Microbiology, University of Strasbourg, CNRS, Strasbourg F-67000, France
| | - Ursula Toth
- Center for Anatomy & Cell Biology, Medical University of Vienna, Vienna A-1090, Austria
| | | | - Konrad U Förstner
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg 97080, Germany.,TH Köln - University of Applied Sciences, Faculty of Information Science and Communication Studies, Institute of Information Science, Cologne D-50678, Germany.,ZB MED - Information Centre for Life Sciences, Cologne D-50931, Germany
| | - Lauriane Kuhn
- Proteomics Platform Strasbourg-Esplanade, FRC1589, IBMC, CNRS, Strasbourg F-67000, France
| | - Johana Chicher
- Proteomics Platform Strasbourg-Esplanade, FRC1589, IBMC, CNRS, Strasbourg F-67000, France
| | - Philippe Hammann
- Proteomics Platform Strasbourg-Esplanade, FRC1589, IBMC, CNRS, Strasbourg F-67000, France
| | - Goran Mitulović
- Proteomics Core Facility, Clinical Department for Laboratory Medicine, Medical University of Vienna, Vienna A-1090, Austria
| | - Nina Entelis
- UMR7156 - Molecular Genetics, Genomics, Microbiology, University of Strasbourg, CNRS, Strasbourg F-67000, France
| | - Ivan Tarassov
- UMR7156 - Molecular Genetics, Genomics, Microbiology, University of Strasbourg, CNRS, Strasbourg F-67000, France
| | - Walter Rossmanith
- Center for Anatomy & Cell Biology, Medical University of Vienna, Vienna A-1090, Austria
| | - Alexandre Smirnov
- UMR7156 - Molecular Genetics, Genomics, Microbiology, University of Strasbourg, CNRS, Strasbourg F-67000, France
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28
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Singh AP, Salvatori R, Aftab W, Kohler A, Carlström A, Forne I, Imhof A, Ott M. Molecular Connectivity of Mitochondrial Gene Expression and OXPHOS Biogenesis. Mol Cell 2020; 79:1051-1065.e10. [PMID: 32877643 DOI: 10.1016/j.molcel.2020.07.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 01/05/2023]
Abstract
Mitochondria contain their own gene expression systems, including membrane-bound ribosomes dedicated to synthesizing a few hydrophobic subunits of the oxidative phosphorylation (OXPHOS) complexes. We used a proximity-dependent biotinylation technique, BioID, coupled with mass spectrometry to delineate in baker's yeast a comprehensive network of factors involved in biogenesis of mitochondrial encoded proteins. This mitochondrial gene expression network (MiGENet) encompasses proteins involved in transcription, RNA processing, translation, or protein biogenesis. Our analyses indicate the spatial organization of these processes, thereby revealing basic mechanistic principles and the proteins populating strategically important sites. For example, newly synthesized proteins are directly handed over to ribosomal tunnel exit-bound factors that mediate membrane insertion, co-factor acquisition, or their mounting into OXPHOS complexes in a special early assembly hub. Collectively, the data reveal the connectivity of mitochondrial gene expression, reflecting a unique tailoring of the mitochondrial gene expression system.
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Affiliation(s)
- Abeer Prakash Singh
- Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden; Department of Medical Biochemistry and Cell Biology, University of Gothenburg, 40530 Gothenburg, Sweden
| | - Roger Salvatori
- Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden; Department of Medical Biochemistry and Cell Biology, University of Gothenburg, 40530 Gothenburg, Sweden
| | - Wasim Aftab
- BioMedical Center, Faculty of Medicine, Ludwig Maximilians University of Munich, 82152 Planegg-Martinsried, Germany; Graduate School for Quantitative Biosciences (QBM), Ludwig Maximilians University of Munich, 81377 Munich, Germany
| | - Andreas Kohler
- Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden
| | - Andreas Carlström
- Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden
| | - Ignasi Forne
- BioMedical Center, Faculty of Medicine, Ludwig Maximilians University of Munich, 82152 Planegg-Martinsried, Germany
| | - Axel Imhof
- BioMedical Center, Faculty of Medicine, Ludwig Maximilians University of Munich, 82152 Planegg-Martinsried, Germany
| | - Martin Ott
- Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden; Department of Medical Biochemistry and Cell Biology, University of Gothenburg, 40530 Gothenburg, Sweden.
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29
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Gao K, Cheng M, Zuo X, Lin J, Hoogewijs K, Murphy MP, Fu XD, Zhang X. Active RNA interference in mitochondria. Cell Res 2020; 31:219-228. [PMID: 32807841 DOI: 10.1038/s41422-020-00394-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/24/2020] [Indexed: 02/06/2023] Open
Abstract
RNA interference (RNAi) has been thought to be a gene-silencing pathway present in most eukaryotic cells to safeguard the genome against retrotransposition. Small interfering RNAs (siRNAs) have also become a powerful tool for studying gene functions. Given the endosymbiotic hypothesis that mitochondria originated from prokaryotes, mitochondria have been generally assumed to lack active RNAi; however, certain bacteria have Argonaute homologs and various reports suggest the presence of specific microRNAs and nuclear genome (nDNA)-encoded Ago2 in the mitochondria. Here we report that transfected siRNAs are not only able to enter the matrix of mitochondria, but also function there to specifically silence targeted mitochondrial transcripts. The mitoRNAi effect is readily detectable at the mRNA level, but only recordable on relatively unstable proteins, such as the mtDNA-encoded complex IV subunits. We also apply mitoRNAi to directly determine the postulated crosstalk between individual respiratory chain complexes, and our result suggests that the controversial observations previously made in patient-derived cells might result from differential adaptation in different cell lines. Our findings bring a new tool to study mitochondrial biology.
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Affiliation(s)
- Kuanxing Gao
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, 430072, China.,Key Laboratory for RNA Biology, Institute of Biophysics, Chinese Academy of Science, Beijing, 100101, China
| | - Man Cheng
- Key Laboratory for RNA Biology, Institute of Biophysics, Chinese Academy of Science, Beijing, 100101, China
| | - Xinxin Zuo
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, Hubei, 430072, China
| | - Jinzhong Lin
- State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200433, China
| | - Kurt Hoogewijs
- Department of Organic and Macromolecular Chemistry, University of Ghent, Ghent, 9000, Belgium
| | - Michael P Murphy
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 1TN, UK.,Department of Medicine, University of Cambridge, Cambridge, CB2 1TN, UK
| | - Xiang-Dong Fu
- Department of Cellular and Molecular Medicine, Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA, 92093-0651, USA.
| | - Xiaorong Zhang
- Key Laboratory for RNA Biology, Institute of Biophysics, Chinese Academy of Science, Beijing, 100101, China.
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30
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Lee RG, Gao J, Siira SJ, Shearwood AM, Ermer JA, Hofferek V, Mathews JC, Zheng M, Reid GE, Rackham O, Filipovska A. Cardiolipin is required for membrane docking of mitochondrial ribosomes and protein synthesis. J Cell Sci 2020; 133:jcs240374. [PMID: 32576663 DOI: 10.1242/jcs.240374] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 06/12/2020] [Indexed: 01/01/2023] Open
Abstract
The mitochondrial inner membrane contains a unique phospholipid known as cardiolipin (CL), which stabilises the protein complexes embedded in the membrane and supports its overall structure. Recent evidence indicates that the mitochondrial ribosome may associate with the inner membrane to facilitate co-translational insertion of the hydrophobic oxidative phosphorylation (OXPHOS) proteins into the inner membrane. We generated three mutant knockout cell lines for the CL biosynthesis gene Crls1 to investigate the effects of CL loss on mitochondrial protein synthesis. Reduced CL levels caused altered mitochondrial morphology and transcriptome-wide changes that were accompanied by uncoordinated mitochondrial translation rates and impaired respiratory chain supercomplex formation. Aberrant protein synthesis was caused by impaired formation and distribution of mitochondrial ribosomes. Reduction or loss of CL resulted in divergent mitochondrial and endoplasmic reticulum stress responses. We show that CL is required to stabilise the interaction of the mitochondrial ribosome with the membrane via its association with OXA1 (also known as OXA1L) during active translation. This interaction facilitates insertion of newly synthesised mitochondrial proteins into the inner membrane and stabilises the respiratory supercomplexes.
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Affiliation(s)
- Richard G Lee
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Junjie Gao
- School of Biomedical Sciences, University of Western Australia, Perth, Australia
| | - Stefan J Siira
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Anne-Marie Shearwood
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Judith A Ermer
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Vinzenz Hofferek
- School of Chemistry, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - James C Mathews
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Minghao Zheng
- School of Biomedical Sciences, University of Western Australia, Perth, Australia
| | - Gavin E Reid
- School of Chemistry, The University of Melbourne, Parkville, Victoria, 3010, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Oliver Rackham
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- School of Pharmacy and Biomedical Sciences, Curtin University, Bentley, Western Australia 6102, Australia
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia 6102, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, 15 Hospital Avenue, Nedlands, Western Australia, Australia
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- Centre for Medical Research, The University of Western Australia, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia 6102, Australia
- Telethon Kids Institute, Northern Entrance, Perth Children's Hospital, 15 Hospital Avenue, Nedlands, Western Australia, Australia
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
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31
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Bogenhagen DF, Haley JD. Pulse-chase SILAC-based analyses reveal selective oversynthesis and rapid turnover of mitochondrial protein components of respiratory complexes. J Biol Chem 2020; 295:2544-2554. [PMID: 31974161 DOI: 10.1074/jbc.ra119.011791] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/17/2020] [Indexed: 12/20/2022] Open
Abstract
Mammalian mitochondria assemble four complexes of the respiratory chain (RCI, RCIII, RCIV, and RCV) by combining 13 polypeptides synthesized within mitochondria on mitochondrial ribosomes (mitoribosomes) with over 70 polypeptides encoded in nuclear DNA, translated on cytoplasmic ribosomes, and imported into mitochondria. We have previously observed that mitoribosome assembly is inefficient because some mitoribosomal proteins are produced in excess, but whether this is the case for other mitochondrial assemblies such as the RCs is unclear. We report here that pulse-chase stable isotope labeling with amino acids in cell culture (SILAC) is a valuable technique to study RC assembly because it can reveal considerable differences in the assembly rates and efficiencies of the different complexes. The SILAC analyses of HeLa cells indicated that assembly of RCV, comprising F1/Fo-ATPase, is rapid with little excess subunit synthesis, but that assembly of RCI (i.e. NADH dehydrogenase) is far less efficient, with dramatic oversynthesis of numerous proteins, particularly in the matrix-exposed N and Q domains. Unassembled subunits were generally degraded within 3 h. We also observed differential assembly kinetics for individual complexes that were immunoprecipitated with complex-specific antibodies. Immunoprecipitation with an antibody that recognizes the ND1 subunit of RCI co-precipitated a number of proteins implicated in FeS cluster assembly and newly synthesized ubiquinol-cytochrome c reductase Rieske iron-sulfur polypeptide 1 (UQCRFS1), the Rieske FeS protein in RCIII, reflecting some coordination between RCI and RCIII assemblies. We propose that pulse-chase SILAC labeling is a useful tool for studying rates of protein complex assembly and degradation.
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Affiliation(s)
- Daniel F Bogenhagen
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York 11794-8651.
| | - John D Haley
- Department of Pathology, Stony Brook University, Stony Brook, New York 11794-8691; Proteomics Center, Stony Brook University, Stony Brook, New York 11794-8691
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32
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Grover R, Burse SA, Shankrit S, Aggarwal A, Kirty K, Narta K, Srivastav R, Ray AK, Malik G, Vats A, Motiani RK, Thukral L, Roy SS, Bhattacharya S, Sharma R, Natarajan K, Mukerji M, Pandey R, Gokhale RS, Natarajan VT. Myg1 exonuclease couples the nuclear and mitochondrial translational programs through RNA processing. Nucleic Acids Res 2019; 47:5852-5866. [PMID: 31081026 PMCID: PMC6582341 DOI: 10.1093/nar/gkz371] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 04/12/2019] [Accepted: 04/30/2019] [Indexed: 01/25/2023] Open
Abstract
Semi-autonomous functioning of mitochondria in eukaryotic cell necessitates coordination with nucleus. Several RNA species fine-tune mitochondrial processes by synchronizing with the nuclear program, however the involved components remain enigmatic. In this study, we identify a widely conserved dually localized protein Myg1, and establish its role as a 3′-5′ RNA exonuclease. We employ mouse melanoma cells, and knockout of the Myg1 ortholog in Saccharomyces cerevisiae with complementation using human Myg1 to decipher the conserved role of Myg1 in selective RNA processing. Localization of Myg1 to nucleolus and mitochondrial matrix was studied through imaging and confirmed by sub-cellular fractionation studies. We developed Silexoseqencing, a methodology to map the RNAse trail at single-nucleotide resolution, and identified in situ cleavage by Myg1 on specific transcripts in the two organelles. In nucleolus, Myg1 processes pre-ribosomal RNA involved in ribosome assembly and alters cytoplasmic translation. In mitochondrial matrix, Myg1 processes 3′-termini of the mito-ribosomal and messenger RNAs and controls translation of mitochondrial proteins. We provide a molecular link to the possible involvement of Myg1 in chronic depigmenting disorder vitiligo. Our study identifies a key component involved in regulating spatially segregated organellar RNA processing and establishes the evolutionarily conserved ribonuclease as a coordinator of nucleo-mitochondrial crosstalk.
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Affiliation(s)
- Ritika Grover
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India.,Academy of Scientific and Innovative Research, Rafi Marg, New Delhi, India
| | - Shaunak A Burse
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India.,Academy of Scientific and Innovative Research, Rafi Marg, New Delhi, India
| | - Shambhavi Shankrit
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Ayush Aggarwal
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India.,Academy of Scientific and Innovative Research, Rafi Marg, New Delhi, India
| | - Kritika Kirty
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Kiran Narta
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Rajpal Srivastav
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Ashwini Kumar Ray
- School of environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Garima Malik
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Archana Vats
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Rajender K Motiani
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Lipi Thukral
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Soumya Sinha Roy
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Sudha Bhattacharya
- School of environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Rakesh Sharma
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | | | - Mitali Mukerji
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Rajesh Pandey
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Rajesh S Gokhale
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India.,National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India
| | - Vivek T Natarajan
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India.,Academy of Scientific and Innovative Research, Rafi Marg, New Delhi, India
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33
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Holt IJ. The mitochondrial R-loop. Nucleic Acids Res 2019; 47:5480-5489. [PMID: 31045202 PMCID: PMC6582354 DOI: 10.1093/nar/gkz277] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/11/2019] [Accepted: 04/29/2019] [Indexed: 12/18/2022] Open
Abstract
The DNA in mitochondria contributes essential components of the organelle’s energy producing machinery that is essential for life. In 1971, many mitochondrial DNA molecules were found to have a third strand of DNA that maps to a region containing critical regulatory elements for transcription and replication. Forty-five years later, a third strand of RNA in the same region has been reported. This mitochondrial R-loop is present on thousands of copies of mitochondrial DNA per cell making it potentially the most abundant R-loop in nature. Here, I assess the discovery of the mitochondrial R-loop, discuss why it remained unrecognized for almost half a century and propose for it central roles in the replication, organization and expression of mitochondrial DNA, which if compromised can lead to disease states.
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Affiliation(s)
- Ian J Holt
- Biodonostia Health Research Institute, 20014 San Sebastián, Spain & IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain.,Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London, NW3 2PF, UK.,CIBERNED (Center for Networked Biomedical Research on Neurodegenerative Diseases, Ministry of Economy and Competitiveness, Institute Carlos III), Madrid, Spain
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34
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Busch JD, Cipullo M, Atanassov I, Bratic A, Silva Ramos E, Schöndorf T, Li X, Pearce SF, Milenkovic D, Rorbach J, Larsson NG. MitoRibo-Tag Mice Provide a Tool for In Vivo Studies of Mitoribosome Composition. Cell Rep 2019; 29:1728-1738.e9. [PMID: 31693908 PMCID: PMC6859486 DOI: 10.1016/j.celrep.2019.09.080] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 08/14/2019] [Accepted: 09/26/2019] [Indexed: 11/16/2022] Open
Abstract
Mitochondria harbor specialized ribosomes (mitoribosomes) necessary for the synthesis of key membrane proteins of the oxidative phosphorylation (OXPHOS) machinery located in the mitochondrial inner membrane. To date, no animal model exists to study mitoribosome composition and mitochondrial translation coordination in mammals in vivo. Here, we create MitoRibo-Tag mice as a tool enabling affinity purification and proteomics analyses of mitoribosomes and their interactome in different tissues. We also define the composition of an assembly intermediate formed in the absence of MTERF4, necessary for a late step in mitoribosomal biogenesis. We identify the orphan protein PUSL1, which interacts with a large subunit assembly intermediate, and demonstrate that it is an inner-membrane-associated mitochondrial matrix protein required for efficient mitochondrial translation. This work establishes MitoRibo-Tag mice as a powerful tool to study mitoribosomes in vivo, enabling future studies on the mitoribosome interactome under different physiological states, as well as in disease and aging. MitoRibo-Tag mice with a tag on mL62 were generated to study mitoribosomes in vivo The mitoribosome interactome of different mouse tissues was defined with proteomics PUSL1 was identified as a mitoribosome-interacting protein using MitoRibo-Tag mice MitoRibo-Tag mice allow mitoribosome analysis under different conditions and setups
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Affiliation(s)
- Jakob D Busch
- Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany; Faculty of Mathematics and Natural Sciences, University of Cologne, Albertus-Magnus-Platz, 50923 Cologne, Germany
| | - Miriam Cipullo
- Department of Medical Biochemistry and Biophysics, Research Division of Molecular Metabolism, Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden; Max-Planck-Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Ilian Atanassov
- Proteomics Core Facility, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Ana Bratic
- Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Eduardo Silva Ramos
- Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Thomas Schöndorf
- Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany; Faculty of Mathematics and Natural Sciences, University of Cologne, Albertus-Magnus-Platz, 50923 Cologne, Germany
| | - Xinping Li
- Proteomics Core Facility, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Sarah F Pearce
- Department of Medical Biochemistry and Biophysics, Research Division of Molecular Metabolism, Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden; Max-Planck-Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Dusanka Milenkovic
- Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany
| | - Joanna Rorbach
- Department of Medical Biochemistry and Biophysics, Research Division of Molecular Metabolism, Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden; Max-Planck-Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.
| | - Nils-Göran Larsson
- Department of Mitochondrial Biology, Max-Planck-Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, 50931 Cologne, Germany; Department of Medical Biochemistry and Biophysics, Research Division of Molecular Metabolism, Karolinska Institutet, Solnavägen 9, 171 65 Solna, Sweden; Max-Planck-Institute for Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.
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Hensen F, Potter A, van Esveld SL, Tarrés-Solé A, Chakraborty A, Solà M, Spelbrink JN. Mitochondrial RNA granules are critically dependent on mtDNA replication factors Twinkle and mtSSB. Nucleic Acids Res 2019; 47:3680-3698. [PMID: 30715486 PMCID: PMC6468249 DOI: 10.1093/nar/gkz047] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 01/16/2019] [Accepted: 01/24/2019] [Indexed: 01/13/2023] Open
Abstract
Newly synthesized mitochondrial RNA is concentrated in structures juxtaposed to nucleoids, called RNA granules, that have been implicated in mitochondrial RNA processing and ribosome biogenesis. Here we show that two classical mtDNA replication factors, the mtDNA helicase Twinkle and single-stranded DNA-binding protein mtSSB, contribute to RNA metabolism in mitochondria and to RNA granule biology. Twinkle colocalizes with both mitochondrial RNA granules and nucleoids, and it can serve as bait to greatly enrich established RNA granule proteins, such as G-rich sequence factor 1, GRSF1. Likewise, mtSSB also is not restricted to the nucleoids, and repression of either mtSSB or Twinkle alters mtRNA metabolism. Short-term Twinkle depletion greatly diminishes RNA granules but does not inhibit RNA synthesis or processing. Either mtSSB or GRSF1 depletion results in RNA processing defects, accumulation of mtRNA breakdown products as well as increased levels of dsRNA and RNA:DNA hybrids. In particular, the processing and degradation defects become more pronounced with both proteins depleted. These findings suggest that Twinkle is essential for RNA organization in granules, and that mtSSB is involved in the recently proposed GRSF1-mtRNA degradosome pathway, a route suggested to be particularly aimed at degradation of G-quadruplex prone long non-coding mtRNAs.
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Affiliation(s)
- Fenna Hensen
- Radboud Center for Mitochondrial Medicine, Department of Paediatrics, Radboudumc, Nijmegen, The Netherlands
| | - Alisa Potter
- Radboud Center for Mitochondrial Medicine, Department of Paediatrics, Radboudumc, Nijmegen, The Netherlands
| | - Selma L van Esveld
- Radboud Center for Mitochondrial Medicine & Center for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen, The Netherlands
| | - Aleix Tarrés-Solé
- Structural MitoLab, Department of Structural Biology, "Maria de Maeztu" Unit of Excellence, Molecular Biology Institute Barcelona (IBMB-CSIC), Barcelona 08028, Spain
| | - Arka Chakraborty
- Structural MitoLab, Department of Structural Biology, "Maria de Maeztu" Unit of Excellence, Molecular Biology Institute Barcelona (IBMB-CSIC), Barcelona 08028, Spain
| | - Maria Solà
- Structural MitoLab, Department of Structural Biology, "Maria de Maeztu" Unit of Excellence, Molecular Biology Institute Barcelona (IBMB-CSIC), Barcelona 08028, Spain
| | - Johannes N Spelbrink
- Radboud Center for Mitochondrial Medicine, Department of Paediatrics, Radboudumc, Nijmegen, The Netherlands
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36
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Perks KL, Rossetti G, Kuznetsova I, Hughes LA, Ermer JA, Ferreira N, Busch JD, Rudler DL, Spahr H, Schöndorf T, Shearwood AMJ, Viola HM, Siira SJ, Hool LC, Milenkovic D, Larsson NG, Rackham O, Filipovska A. PTCD1 Is Required for 16S rRNA Maturation Complex Stability and Mitochondrial Ribosome Assembly. Cell Rep 2019; 23:127-142. [PMID: 29617655 DOI: 10.1016/j.celrep.2018.03.033] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/31/2018] [Accepted: 03/08/2018] [Indexed: 12/25/2022] Open
Abstract
The regulation of mitochondrial RNA life cycles and their roles in ribosome biogenesis and energy metabolism are not fully understood. We used CRISPR/Cas9 to generate heart- and skeletal-muscle-specific knockout mice of the pentatricopeptide repeat domain protein 1, PTCD1, and show that its loss leads to severe cardiomyopathy and premature death. Our detailed transcriptome-wide and functional analyses of these mice enabled us to identify the molecular role of PTCD1 as a 16S rRNA-binding protein essential for its stability, pseudouridylation, and correct biogenesis of the mitochondrial large ribosomal subunit. We show that impaired mitoribosome biogenesis can have retrograde signaling effects on nuclear gene expression through the transcriptional activation of the mTOR pathway and upregulation of cytoplasmic protein synthesis and pro-survival factors in the absence of mitochondrial translation. Taken together, our data show that impaired assembly of the mitoribosome exerts its consequences via differential regulation of mitochondrial and cytoplasmic protein synthesis.
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Affiliation(s)
- Kara L Perks
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Giulia Rossetti
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Irina Kuznetsova
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Laetitia A Hughes
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Judith A Ermer
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Nicola Ferreira
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Jakob D Busch
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Danielle L Rudler
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Henrik Spahr
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Thomas Schöndorf
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Ann-Marie J Shearwood
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Helena M Viola
- School of Human Sciences (Physiology), The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Stefan J Siira
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Livia C Hool
- School of Human Sciences (Physiology), The University of Western Australia, Crawley, Western Australia 6009, Australia; Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Dusanka Milenkovic
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Nils-Göran Larsson
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany; Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden
| | - Oliver Rackham
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia; School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research, Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, Western Australia 6009, Australia; School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia.
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37
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Baechler SA, Dalla Rosa I, Spinazzola A, Pommier Y. Beyond the unwinding: role of TOP1MT in mitochondrial translation. Cell Cycle 2019; 18:2377-2384. [PMID: 31345095 DOI: 10.1080/15384101.2019.1646563] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mitochondria contain their own genome (mtDNA), encoding 13 proteins of the enzyme complexes of the oxidative phosphorylation. Synthesis of these 13 mitochondrial proteins requires a specific translation machinery, the mitoribosomes whose RNA components are encoded by the mtDNA, whereas more than 80 proteins are encoded by nuclear genes. It has been well established that mitochondrial topoisomerase I (TOP1MT) is important for mtDNA integrity and mitochondrial transcription as it prevents excessive mtDNA negative supercoiling and releases topological stress during mtDNA replication and transcription. We recently showed that TOP1MT also supports mitochondrial protein synthesis, and thus is critical for promoting tumor growth. Impaired mitochondrial protein synthesis leads to activation of the mitonuclear stress response through the transcription factor ATF4, and induces cytoprotective genes in order to prevent mitochondrial and cellular dysfunction. In this perspective, we highlight the novel role of TOP1MT in mitochondrial protein synthesis and as potential target for chemotherapy.
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Affiliation(s)
- Simone A Baechler
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH , Bethesda , MD , USA
| | - Ilaria Dalla Rosa
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology , London , UK
| | - Antonella Spinazzola
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology , London , UK
| | - Yves Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH , Bethesda , MD , USA
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38
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Pajak A, Laine I, Clemente P, El-Fissi N, Schober FA, Maffezzini C, Calvo-Garrido J, Wibom R, Filograna R, Dhir A, Wedell A, Freyer C, Wredenberg A. Defects of mitochondrial RNA turnover lead to the accumulation of double-stranded RNA in vivo. PLoS Genet 2019; 15:e1008240. [PMID: 31365523 PMCID: PMC6668790 DOI: 10.1371/journal.pgen.1008240] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 06/11/2019] [Indexed: 12/02/2022] Open
Abstract
The RNA helicase SUV3 and the polynucleotide phosphorylase PNPase are involved in the degradation of mitochondrial mRNAs but their roles in vivo are not fully understood. Additionally, upstream processes, such as transcript maturation, have been linked to some of these factors, suggesting either dual roles or tightly interconnected mechanisms of mitochondrial RNA metabolism. To get a better understanding of the turn-over of mitochondrial RNAs in vivo, we manipulated the mitochondrial mRNA degrading complex in Drosophila melanogaster models and studied the molecular consequences. Additionally, we investigated if and how these factors interact with the mitochondrial poly(A) polymerase, MTPAP, as well as with the mitochondrial mRNA stabilising factor, LRPPRC. Our results demonstrate a tight interdependency of mitochondrial mRNA stability, polyadenylation and the removal of antisense RNA. Furthermore, disruption of degradation, as well as polyadenylation, leads to the accumulation of double-stranded RNAs, and their escape out into the cytoplasm is associated with an altered immune-response in flies. Together our results suggest a highly organised and inter-dependable regulation of mitochondrial RNA metabolism with far reaching consequences on cellular physiology. Although a number of factors have been implemented in the turnover of mitochondrial (mt) DNA-derived transcripts, their exact functions and interplay with one another is not entirely clear. Several of these factors have been proposed to co-ordinately regulate both transcript maturation, as well as degradation, but the order of events during mitochondrial RNA turnover is less well understood. Using a range of different genetically modified Drosophila melanogaster models, we studied the involvement of the RNA helicase SUV3, the polynucleotide phosphorylase PNPase, the leucine-rich pentatricopeptide repeat motif-containing protein LRPPRC, and the mitochondrial RNA poly(A) polymerase MTPAP, in stabilisation, polyadenylation, and degradation of mitochondrial transcripts. Our results show a tight collaborative activity of these factors in vivo and reveal a clear hierarchical order of events leading to mitochondrial mRNA maturation. Furthermore, we demonstrate that the loss of SUV3, PNPase, or MTPAP leads to the accumulation of mitochondrial-derived antisense RNA in the cytoplasm of cells, which is associated with an altered immune-response in flies.
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Affiliation(s)
- Aleksandra Pajak
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Isabelle Laine
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Paula Clemente
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Najla El-Fissi
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Florian A. Schober
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Camilla Maffezzini
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Javier Calvo-Garrido
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Rolf Wibom
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Roberta Filograna
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Ashish Dhir
- Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Anna Wedell
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Christoph Freyer
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
- * E-mail: (CF); (AW)
| | - Anna Wredenberg
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
- Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
- * E-mail: (CF); (AW)
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39
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Kinetics and Mechanism of Mammalian Mitochondrial Ribosome Assembly. Cell Rep 2019; 22:1935-1944. [PMID: 29444443 DOI: 10.1016/j.celrep.2018.01.066] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 11/01/2017] [Accepted: 01/22/2018] [Indexed: 01/08/2023] Open
Abstract
Mammalian mtDNA encodes only 13 proteins, all essential components of respiratory complexes, synthesized by mitochondrial ribosomes. Mitoribosomes contain greatly truncated RNAs transcribed from mtDNA, including a structural tRNA in place of 5S RNA as a scaffold for binding 82 nucleus-encoded proteins, mitoribosomal proteins (MRPs). Cryoelectron microscopy (cryo-EM) studies have determined the structure of the mitoribosome, but its mechanism of assembly is unknown. Our SILAC pulse-labeling experiments determine the rates of mitochondrial import of MRPs and their assembly into intact mitoribosomes, providing a basis for distinguishing MRPs that bind at early and late stages in mitoribosome assembly to generate a working model for mitoribosome assembly. Mitoribosome assembly is a slow process initiated at the mtDNA nucleoid driven by excess synthesis of individual MRPs. MRPs that are tightly associated in the structure frequently join the complex in a coordinated manner. Clinically significant MRP mutations reported to date affect proteins that bind early on during assembly.
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40
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Trinkle-Mulcahy L. Mapping New Residents of the Mitochondrial Nucleoid. Cell Chem Biol 2019; 24:250-251. [PMID: 28306501 DOI: 10.1016/j.chembiol.2017.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this issue of Cell Chemical Biology, Han et al. (2017) used a powerful combination of quantitative ratiometric mass spectrometry with APEX peroxidase-catalyzed proximity biotinylation to selectively highlight proteins associated with mitochondrial DNA above the background of contaminants and matrix proteins. In addition to identifying novel nucleoid factors, this study extends the APEX strategy to the proteomic mapping of non-membrane-bound multiprotein complexes.
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Affiliation(s)
- Laura Trinkle-Mulcahy
- Department of Cellular and Molecular Medicine and Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
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41
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Durigon R, Mitchell AL, Jones AW, Manole A, Mennuni M, Hirst EM, Houlden H, Maragni G, Lattante S, Doronzio PN, Dalla Rosa I, Zollino M, Holt IJ, Spinazzola A. LETM1 couples mitochondrial DNA metabolism and nutrient preference. EMBO Mol Med 2019; 10:emmm.201708550. [PMID: 30012579 PMCID: PMC6127893 DOI: 10.15252/emmm.201708550] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The diverse clinical phenotypes of Wolf–Hirschhorn syndrome (WHS) are the result of haploinsufficiency of several genes, one of which, LETM1, encodes a protein of the mitochondrial inner membrane of uncertain function. Here, we show that LETM1 is associated with mitochondrial ribosomes, is required for mitochondrial DNA distribution and expression, and regulates the activity of an ancillary metabolic enzyme, pyruvate dehydrogenase. LETM1 deficiency in WHS alters mitochondrial morphology and DNA organization, as does substituting ketone bodies for glucose in control cells. While this change in nutrient availability leads to the death of fibroblasts with normal amounts of LETM1, WHS‐derived fibroblasts survive on ketone bodies, which can be attributed to their reduced dependence on glucose oxidation. Thus, remodeling of mitochondrial nucleoprotein complexes results from the inability of mitochondria to use specific substrates for energy production and is indicative of mitochondrial dysfunction. However, the dysfunction could be mitigated by a modified diet—for WHS, one high in lipids and low in carbohydrates.
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Affiliation(s)
- Romina Durigon
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK
| | - Alice L Mitchell
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK
| | - Aleck We Jones
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK
| | - Andreea Manole
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK.,Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
| | - Mara Mennuni
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK
| | | | - Henry Houlden
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK.,Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
| | | | - Serena Lattante
- Institute of Genomic Medicine, Catholic University, Rome, Italy
| | | | - Ilaria Dalla Rosa
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK
| | | | - Ian J Holt
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK.,Biodonostia Health Research Institute, San Sebastián, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Antonella Spinazzola
- Department of Clinical and Movement Neurosciences, UCL Institute of Neurology, London, UK .,MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK
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42
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Guedes-Monteiro RF, Franco LV, Moda BS, Tzagoloff A, Barros MH. 5′ processing of Saccharomyces cerevisiae mitochondrial tRNAs requires expression of multiple genes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:806-818. [DOI: 10.1016/j.bbamcr.2019.02.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 01/31/2019] [Accepted: 02/03/2019] [Indexed: 01/02/2023]
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43
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Jiang S, Koolmeister C, Misic J, Siira S, Kühl I, Silva Ramos E, Miranda M, Jiang M, Posse V, Lytovchenko O, Atanassov I, Schober FA, Wibom R, Hultenby K, Milenkovic D, Gustafsson CM, Filipovska A, Larsson NG. TEFM regulates both transcription elongation and RNA processing in mitochondria. EMBO Rep 2019; 20:embr.201948101. [PMID: 31036713 PMCID: PMC6549021 DOI: 10.15252/embr.201948101] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 03/29/2019] [Accepted: 04/02/2019] [Indexed: 12/22/2022] Open
Abstract
Regulation of replication and expression of mitochondrial DNA (mtDNA) is essential for cellular energy conversion via oxidative phosphorylation. The mitochondrial transcription elongation factor (TEFM) has been proposed to regulate the switch between transcription termination for replication primer formation and processive, near genome‐length transcription for mtDNA gene expression. Here, we report that Tefm is essential for mouse embryogenesis and that levels of promoter‐distal mitochondrial transcripts are drastically reduced in conditional Tefm‐knockout hearts. In contrast, the promoter‐proximal transcripts are much increased in Tefm knockout mice, but they mostly terminate before the region where the switch from transcription to replication occurs, and consequently, de novo mtDNA replication is profoundly reduced. Unexpectedly, deep sequencing of RNA from Tefm knockouts revealed accumulation of unprocessed transcripts in addition to defective transcription elongation. Furthermore, a proximity‐labeling (BioID) assay showed that TEFM interacts with multiple RNA processing factors. Our data demonstrate that TEFM acts as a general transcription elongation factor, necessary for both gene transcription and replication primer formation, and loss of TEFM affects RNA processing in mammalian mitochondria.
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Affiliation(s)
- Shan Jiang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Camilla Koolmeister
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Jelena Misic
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Stefan Siira
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Perth, WA, Australia
| | - Inge Kühl
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany.,Institute of Integrative Biology of the Cell, UMR9198, CEA, CNRS, University Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Eduardo Silva Ramos
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Maria Miranda
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Min Jiang
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Viktor Posse
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Oleksandr Lytovchenko
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Ilian Atanassov
- Proteomics Core Facility, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Florian A Schober
- Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.,Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Rolf Wibom
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.,Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Kjell Hultenby
- Division of Clinical Research Centre, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Dusanka Milenkovic
- Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Claes M Gustafsson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Perth, WA, Australia
| | - Nils-Göran Larsson
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden .,Max Planck Institute Biology of Ageing - Karolinska Institutet Laboratory, Karolinska Institutet, Stockholm, Sweden.,Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany.,Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
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44
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Norris V. Successive Paradigm Shifts in the Bacterial Cell Cycle and Related Subjects. Life (Basel) 2019; 9:E27. [PMID: 30866455 PMCID: PMC6462897 DOI: 10.3390/life9010027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 11/26/2022] Open
Abstract
A paradigm shift in one field can trigger paradigm shifts in other fields. This is illustrated by the paradigm shifts that have occurred in bacterial physiology following the discoveries that bacteria are not unstructured, that the bacterial cell cycle is not controlled by the dynamics of peptidoglycan, and that the growth rates of bacteria in the same steady-state population are not at all the same. These paradigm shifts are having an effect on longstanding hypotheses about the regulation of the bacterial cell cycle, which appear increasingly to be inadequate. I argue that, just as one earthquake can trigger others, an imminent paradigm shift in the regulation of the bacterial cell cycle will have repercussions or "paradigm quakes" on hypotheses about the origins of life and about the regulation of the eukaryotic cell cycle.
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Affiliation(s)
- Vic Norris
- Laboratory of Microbiology Signals and Microenvironment, University of Rouen, 76821 Mont Saint Aignan, France.
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45
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Baechler SA, Factor VM, Dalla Rosa I, Ravji A, Becker D, Khiati S, Miller Jenkins LM, Lang M, Sourbier C, Michaels SA, Neckers LM, Zhang HL, Spinazzola A, Huang SN, Marquardt JU, Pommier Y. The mitochondrial type IB topoisomerase drives mitochondrial translation and carcinogenesis. Nat Commun 2019; 10:83. [PMID: 30622257 PMCID: PMC6325124 DOI: 10.1038/s41467-018-07922-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/28/2018] [Indexed: 01/23/2023] Open
Abstract
Mitochondrial topoisomerase IB (TOP1MT) is a nuclear-encoded topoisomerase, exclusively localized to mitochondria, which resolves topological stress generated during mtDNA replication and transcription. Here, we report that TOP1MT is overexpressed in cancer tissues and demonstrate that TOP1MT deficiency attenuates tumor growth in human and mouse models of colon and liver cancer. Due to their mitochondrial dysfunction, TOP1MT-KO cells become addicted to glycolysis, which limits synthetic building blocks and energy supply required for the proliferation of cancer cells in a nutrient-deprived tumor microenvironment. Mechanistically, we show that TOP1MT associates with mitoribosomal subunits, ensuring optimal mitochondrial translation and assembly of oxidative phosphorylation complexes that are critical for sustaining tumor growth. The TOP1MT genomic signature profile, based on Top1mt-KO liver cancers, is correlated with enhanced survival of hepatocellular carcinoma patients. Our results highlight the importance of TOP1MT for tumor development, providing a potential rationale to develop TOP1MT-targeted drugs as anticancer therapies.
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MESH Headings
- Animals
- Carcinogenesis/pathology
- Carcinogens/toxicity
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/mortality
- Carcinoma, Hepatocellular/pathology
- Cell Nucleus/metabolism
- Cell Proliferation
- DNA Topoisomerases, Type I/genetics
- DNA Topoisomerases, Type I/metabolism
- DNA, Mitochondrial/genetics
- DNA, Mitochondrial/isolation & purification
- Datasets as Topic
- Energy Metabolism
- Female
- Fibroblasts
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Glycolysis
- HCT116 Cells
- Humans
- Liver/cytology
- Liver/metabolism
- Liver/pathology
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/mortality
- Liver Neoplasms/pathology
- Liver Neoplasms, Experimental/chemically induced
- Liver Neoplasms, Experimental/genetics
- Liver Neoplasms, Experimental/metabolism
- Liver Neoplasms, Experimental/pathology
- Male
- Mice
- Mice, Knockout
- Mice, Nude
- Mitochondria/metabolism
- Mitochondria/pathology
- Prognosis
- Protein Biosynthesis
- Survival Analysis
- Xenograft Model Antitumor Assays
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Affiliation(s)
- S A Baechler
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - V M Factor
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - I Dalla Rosa
- Department of Clinical and Movement Neurosciences, Institute of Neurology, Royal Free Campus, University College London, London, NW3 2PF, UK
| | - A Ravji
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - D Becker
- Department of Medicine I, Johannes Gutenberg University, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - S Khiati
- Equipe MitoLab, Institut MitoVasc, UMR CNRS 6015, INSERM U1083, Universite d'Angers, 49933, Angers, France
| | - L M Miller Jenkins
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - M Lang
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MA, 20892, USA
| | - C Sourbier
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MA, 20892, USA
- Laboratory of Molecular Oncology, Division of Biotechnology Review and Research I, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - S A Michaels
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - L M Neckers
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MA, 20892, USA
| | - H L Zhang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - A Spinazzola
- Department of Clinical and Movement Neurosciences, Institute of Neurology, Royal Free Campus, University College London, London, NW3 2PF, UK
| | - S N Huang
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA
| | - J U Marquardt
- Department of Medicine I, Johannes Gutenberg University, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Y Pommier
- Laboratory of Molecular Pharmacology, Developmental Therapeutics Branch, Center for Cancer Research, NIH, National Cancer Institute, Bethesda, Maryland, 20892, USA.
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46
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Shang J, Wu L, Yang Y, Li Y, Liu Z, Huang Y. Overexpression of Schizosaccharomyces pombe tRNA 3′-end processing enzyme Trz2 leads to an increased cellular iron level and apoptotic cell death. Fungal Genet Biol 2019; 122:11-20. [DOI: 10.1016/j.fgb.2018.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 10/10/2018] [Accepted: 10/23/2018] [Indexed: 01/18/2023]
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47
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Pulse SILAC Approaches to the Measurement of Cellular Dynamics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1140:575-583. [DOI: 10.1007/978-3-030-15950-4_34] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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48
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Maiti P, Kim HJ, Tu YT, Barrientos A. Human GTPBP10 is required for mitoribosome maturation. Nucleic Acids Res 2018; 46:11423-11437. [PMID: 30321378 PMCID: PMC6265488 DOI: 10.1093/nar/gky938] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 09/18/2018] [Accepted: 10/05/2018] [Indexed: 01/07/2023] Open
Abstract
Most steps on the biogenesis of the mitochondrial ribosome (mitoribosome) occur near the mitochondrial DNA nucleoid, in RNA granules, which contain dedicated RNA metabolism and mitoribosome assembly factors. Here, analysis of the RNA granule proteome identified the presence of a set of small GTPases that belong to conserved families of ribosome assembly factors. We show that GTPBP10, a member of the conserved Obg family of P-loop small G proteins, is a mitochondrial protein and have used gene-editing technologies to create a HEK293T cell line KO for GTPBP10. The absence of GTPBP10 leads to attenuated mtLSU and mtSSU levels and the virtual absence of the 55S monosome, which entirely prevents mitochondrial protein synthesis. We show that a fraction of GTPBP10 cosediments with the large mitoribosome subunit and the monosome. GTPBP10 physically interacts with the 16S rRNA, but not with the 12S rRNA, and crosslinks with several mtLSU proteins. Additionally, GTPBP10 is indirectly required for efficient processing of the 12S-16S rRNA precursor transcript, which could explain the mtSSU accumulation defect. We propose that GTPBP10 primarily ensures proper mtLSU maturation and ultimately serves to coordinate mtSSU and mtLSU accumulation then providing a quality control check-point function during mtLSU assembly that minimizes premature subunit joining.
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Affiliation(s)
- Priyanka Maiti
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Hyun-Jung Kim
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Ya-Ting Tu
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Antoni Barrientos
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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49
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Reinhard L, Sridhara S, Hällberg BM. The MRPP1/MRPP2 complex is a tRNA-maturation platform in human mitochondria. Nucleic Acids Res 2017; 45:12469-12480. [PMID: 29040705 PMCID: PMC5716156 DOI: 10.1093/nar/gkx902] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/25/2017] [Indexed: 11/22/2022] Open
Abstract
Mitochondrial polycistronic transcripts are extensively processed to give rise to functional mRNAs, rRNAs and tRNAs; starting with the release of tRNA elements through 5′-processing by RNase P (MRPP1/2/3-complex) and 3′-processing by RNase Z (ELAC2). Here, we show using in vitro experiments that MRPP1/2 is not only a component of the mitochondrial RNase P but that it retains the tRNA product from the 5′-processing step and significantly enhances the efficiency of ELAC2-catalyzed 3′-processing for 17 of the 22 tRNAs encoded in the human mitochondrial genome. Furthermore, MRPP1/2 retains the tRNA product after ELAC2 processing and presents the nascent tRNA to the mitochondrial CCA-adding enzyme. Thus, in addition to being an essential component of the RNase P reaction, MRPP1/2 serves as a processing platform for several down-stream tRNA maturation steps in human mitochondria. These findings are of fundamental importance for our molecular understanding of disease-related mutations in MRPP1/2, ELAC2 and mitochondrial tRNA genes.
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Affiliation(s)
- Linda Reinhard
- Department of Cell and Molecular Biology, Karolinska Institutet, 17177 Stockholm, Sweden.,Röntgen-Ångström-Cluster, Karolinska Institutet Outstation, Centre for Structural Systems Biology (CSSB), DESY-Campus, 22607 Hamburg, Germany
| | - Sagar Sridhara
- Department of Cell and Molecular Biology, Karolinska Institutet, 17177 Stockholm, Sweden.,Röntgen-Ångström-Cluster, Karolinska Institutet Outstation, Centre for Structural Systems Biology (CSSB), DESY-Campus, 22607 Hamburg, Germany
| | - B Martin Hällberg
- Department of Cell and Molecular Biology, Karolinska Institutet, 17177 Stockholm, Sweden.,Röntgen-Ångström-Cluster, Karolinska Institutet Outstation, Centre for Structural Systems Biology (CSSB), DESY-Campus, 22607 Hamburg, Germany.,European Molecular Biology Laboratory, Hamburg Unit, 22603 Hamburg, Germany
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50
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Kuznetsova I, Siira SJ, Shearwood AMJ, Ermer JA, Filipovska A, Rackham O. Simultaneous processing and degradation of mitochondrial RNAs revealed by circularized RNA sequencing. Nucleic Acids Res 2017; 45:5487-5500. [PMID: 28201688 PMCID: PMC5435911 DOI: 10.1093/nar/gkx104] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 02/07/2017] [Indexed: 12/14/2022] Open
Abstract
Mammalian mitochondrial RNAs are unique as they are derived from primary transcripts that encompass almost the entire mitochondrial genome. This necessitates extensive processing to release the individual mRNAs, rRNAs and tRNAs required for gene expression. Recent studies have revealed many of the proteins required for mitochondrial RNA processing, however the rapid turnover of precursor RNAs has made it impossible to analyze their composition and the hierarchy of processing. Here, we find that circularization of RNA prior to deep sequencing enables the discovery and characterization of unprocessed RNAs. Using this approach, we identify the most stable processing intermediates and the presence of intermediate processing products that are partially degraded and polyadenylated. Analysis of libraries constructed using RNA from mice lacking the nuclease subunit of the mitochondrial RNase P reveals the identities of stalled processing intermediates, their order of cleavage, and confirms the importance of RNase P in generating mature mitochondrial RNAs. Using RNA circularization prior to library preparation should provide a generally useful approach to studying RNA processing in many different biological systems.
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Affiliation(s)
- Irina Kuznetsova
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
| | - Stefan J. Siira
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
| | - Anne-Marie J. Shearwood
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
| | - Judith A. Ermer
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
- School of Molecular Sciences, The University of Western Australia, Crawley 6009, Australia
| | - Oliver Rackham
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands 6009, Australia
- School of Molecular Sciences, The University of Western Australia, Crawley 6009, Australia
- To whom correspondence should be addressed. Tel: +61 8 6151 0735; Fax: +61 8 9463 1469;
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