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Nieto-Panqueva F, Vázquez-Acevedo M, Hamel PP, González-Halphen D. Identification of factors limiting the allotopic production of the Cox2 subunit of yeast cytochrome c oxidase. Genetics 2024; 227:iyae058. [PMID: 38626319 DOI: 10.1093/genetics/iyae058] [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: 03/01/2024] [Revised: 03/29/2024] [Accepted: 04/01/2024] [Indexed: 04/18/2024] Open
Abstract
Mitochondrial genes can be artificially relocalized in the nuclear genome in a process known as allotopic expression, such is the case of the mitochondrial cox2 gene, encoding subunit II of cytochrome c oxidase (CcO). In yeast, cox2 can be allotopically expressed and is able to restore respiratory growth of a cox2-null mutant if the Cox2 subunit carries the W56R substitution within the first transmembrane stretch. However, the COX2W56R strain exhibits reduced growth rates and lower steady-state CcO levels when compared to wild-type yeast. Here, we investigated the impact of overexpressing selected candidate genes predicted to enhance internalization of the allotopic Cox2W56R precursor into mitochondria. The overproduction of Cox20, Oxa1, and Pse1 facilitated Cox2W56R precursor internalization, improving the respiratory growth of the COX2W56R strain. Overproducing TIM22 components had a limited effect on Cox2W56R import, while overproducing TIM23-related components showed a negative effect. We further explored the role of the Mgr2 subunit within the TIM23 translocator in the import process by deleting and overexpressing the MGR2 gene. Our findings indicate that Mgr2 is instrumental in modulating the TIM23 translocon to correctly sort Cox2W56R. We propose a biogenesis pathway followed by the allotopically produced Cox2 subunit based on the participation of the 2 different structural/functional forms of the TIM23 translocon, TIM23MOTOR and TIM23SORT, that must follow a concerted and sequential mode of action to insert Cox2W56R into the inner mitochondrial membrane in the correct Nout-Cout topology.
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Affiliation(s)
- Felipe Nieto-Panqueva
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-243, 04510 D.F. (Mexico), México
| | - Miriam Vázquez-Acevedo
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-243, 04510 D.F. (Mexico), México
| | - Patrice P Hamel
- Department of Molecular Genetics and Department of Biological Chemistry and Pharmacology, The Ohio State University, 582 Aronoff laboratory, 318 W. 12th Avenue, Columbus, OH 43210, USA
- School of BioScience and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, 632 014, India
| | - Diego González-Halphen
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-243, 04510 D.F. (Mexico), México
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2
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Horten P, Song K, Garlich J, Hardt R, Colina-Tenorio L, Horvath SE, Schulte U, Fakler B, van der Laan M, Becker T, Stuart RA, Pfanner N, Rampelt H. Identification of MIMAS, a multifunctional mega-assembly integrating metabolic and respiratory biogenesis factors of mitochondria. Cell Rep 2024; 43:113772. [PMID: 38393949 PMCID: PMC11010658 DOI: 10.1016/j.celrep.2024.113772] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 01/03/2024] [Accepted: 01/24/2024] [Indexed: 02/25/2024] Open
Abstract
The mitochondrial inner membrane plays central roles in bioenergetics and metabolism and contains several established membrane protein complexes. Here, we report the identification of a mega-complex of the inner membrane, termed mitochondrial multifunctional assembly (MIMAS). Its large size of 3 MDa explains why MIMAS has escaped detection in the analysis of mitochondria so far. MIMAS combines proteins of diverse functions from respiratory chain assembly to metabolite transport, dehydrogenases, and lipid biosynthesis but not the large established supercomplexes of the respiratory chain, ATP synthase, or prohibitin scaffold. MIMAS integrity depends on the non-bilayer phospholipid phosphatidylethanolamine, in contrast to respiratory supercomplexes whose stability depends on cardiolipin. Our findings suggest that MIMAS forms a protein-lipid mega-assembly in the mitochondrial inner membrane that integrates respiratory biogenesis and metabolic processes in a multifunctional platform.
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Affiliation(s)
- Patrick Horten
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Kuo Song
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Joshua Garlich
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233, USA
| | - Robert Hardt
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, 53115 Bonn, Germany
| | - Lilia Colina-Tenorio
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Susanne E Horvath
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Uwe Schulte
- Institute of Physiology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Bernd Fakler
- Institute of Physiology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Martin van der Laan
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Faculty of Medicine, Saarland University, 66421 Homburg, Germany
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, 53115 Bonn, Germany
| | - Rosemary A Stuart
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233, USA
| | - Nikolaus Pfanner
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
| | - Heike Rampelt
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
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3
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Kizmaz B, Herrmann JM. Membrane insertases at a glance. J Cell Sci 2023; 136:jcs261219. [PMID: 37417332 DOI: 10.1242/jcs.261219] [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] [Indexed: 07/08/2023] Open
Abstract
Protein translocases, such as the bacterial SecY complex, the Sec61 complex of the endoplasmic reticulum (ER) and the mitochondrial translocases, facilitate the transport of proteins across membranes. In addition, they catalyze the insertion of integral membrane proteins into the lipid bilayer. Several membrane insertases cooperate with these translocases, thereby promoting the topogenesis, folding and assembly of membrane proteins. Oxa1 and BamA family members serve as core components in the two major classes of membrane insertases. They facilitate the integration of proteins with α-helical transmembrane domains and of β-barrel proteins into lipid bilayers, respectively. Members of the Oxa1 family were initially found in the internal membranes of bacteria, mitochondria and chloroplasts. Recent studies, however, also identified several Oxa1-type insertases in the ER, where they serve as catalytically active core subunits in the ER membrane protein complex (EMC), the guided entry of tail-anchored (GET) and the GET- and EMC-like (GEL) complex. The outer membrane of bacteria, mitochondria and chloroplasts contain β-barrel proteins, which are inserted by members of the BamA family. In this Cell Science at a Glance article and the accompanying poster, we provide an overview of these different types of membrane insertases and discuss their function.
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Affiliation(s)
- Büsra Kizmaz
- Cell Biology, University of Kaiserslautern, Kaiserslautern 67663, Germany
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4
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Güngör B, Flohr T, Garg SG, Herrmann JM. The ER membrane complex (EMC) can functionally replace the Oxa1 insertase in mitochondria. PLoS Biol 2022; 20:e3001380. [PMID: 35231030 PMCID: PMC8887752 DOI: 10.1371/journal.pbio.3001380] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 12/17/2021] [Indexed: 12/18/2022] Open
Abstract
Two multisubunit protein complexes for membrane protein insertion were recently identified in the endoplasmic reticulum (ER): the guided entry of tail anchor proteins (GET) complex and ER membrane complex (EMC). The structures of both of their hydrophobic core subunits, which are required for the insertion reaction, revealed an overall similarity to the YidC/Oxa1/Alb3 family members found in bacteria, mitochondria, and chloroplasts. This suggests that these membrane insertion machineries all share a common ancestry. To test whether these ER proteins can functionally replace Oxa1 in yeast mitochondria, we generated strains that express mitochondria-targeted Get2-Get1 and Emc6-Emc3 fusion proteins in Oxa1 deletion mutants. Interestingly, the Emc6-Emc3 fusion was able to complement an Δoxa1 mutant and restored its respiratory competence. The Emc6-Emc3 fusion promoted the insertion of the mitochondrially encoded protein Cox2, as well as of nuclear encoded inner membrane proteins, although was not able to facilitate the assembly of the Atp9 ring. Our observations indicate that protein insertion into the ER is functionally conserved to the insertion mechanism in bacteria and mitochondria and adheres to similar topological principles.
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Affiliation(s)
- Büsra Güngör
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Tamara Flohr
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Sriram G. Garg
- Institute for Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
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Franco LVR, Su CH, Tzagoloff A. Modular assembly of yeast mitochondrial ATP synthase and cytochrome oxidase. Biol Chem 2021; 401:835-853. [PMID: 32142477 DOI: 10.1515/hsz-2020-0112] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 02/24/2020] [Indexed: 12/27/2022]
Abstract
The respiratory pathway of mitochondria is composed of four electron transfer complexes and the ATP synthase. In this article, we review evidence from studies of Saccharomyces cerevisiae that both ATP synthase and cytochrome oxidase (COX) are assembled from independent modules that correspond to structurally and functionally identifiable components of each complex. Biogenesis of the respiratory chain requires a coordinate and balanced expression of gene products that become partner subunits of the same complex, but are encoded in the two physically separated genomes. Current evidence indicates that synthesis of two key mitochondrial encoded subunits of ATP synthase is regulated by the F1 module. Expression of COX1 that codes for a subunit of the COX catalytic core is also regulated by a mechanism that restricts synthesis of this subunit to the availability of a nuclear-encoded translational activator. The respiratory chain must maintain a fixed stoichiometry of the component enzyme complexes during cell growth. We propose that high-molecular-weight complexes composed of Cox6, a subunit of COX, and of the Atp9 subunit of ATP synthase play a key role in establishing the ratio of the two complexes during their assembly.
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Affiliation(s)
- Leticia Veloso Ribeiro Franco
- Department of Biological Sciences, Columbia University, New York City, NY 10027, USA.,Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, 05508-000, Brasil
| | - Chen Hsien Su
- Department of Biological Sciences, Columbia University, New York City, NY 10027, USA
| | - Alexander Tzagoloff
- Department of Biological Sciences, Columbia University, New York City, NY 10027, USA
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6
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Functions of Cytochrome c oxidase Assembly Factors. Int J Mol Sci 2020; 21:ijms21197254. [PMID: 33008142 PMCID: PMC7582755 DOI: 10.3390/ijms21197254] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 09/23/2020] [Indexed: 12/22/2022] Open
Abstract
Cytochrome c oxidase is the terminal complex of eukaryotic oxidative phosphorylation in mitochondria. This process couples the reduction of electron carriers during metabolism to the reduction of molecular oxygen to water and translocation of protons from the internal mitochondrial matrix to the inter-membrane space. The electrochemical gradient formed is used to generate chemical energy in the form of adenosine triphosphate to power vital cellular processes. Cytochrome c oxidase and most oxidative phosphorylation complexes are the product of the nuclear and mitochondrial genomes. This poses a series of topological and temporal steps that must be completed to ensure efficient assembly of the functional enzyme. Many assembly factors have evolved to perform these steps for insertion of protein into the inner mitochondrial membrane, maturation of the polypeptide, incorporation of co-factors and prosthetic groups and to regulate this process. Much of the information about each of these assembly factors has been gleaned from use of the single cell eukaryote Saccharomyces cerevisiae and also mutations responsible for human disease. This review will focus on the assembly factors of cytochrome c oxidase to highlight some of the outstanding questions in the assembly of this vital enzyme complex.
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7
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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: 28] [Impact Index Per Article: 7.0] [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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8
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Koripella RK, Sharma MR, Bhargava K, Datta PP, Kaushal PS, Keshavan P, Spremulli LL, Banavali NK, Agrawal RK. Structures of the human mitochondrial ribosome bound to EF-G1 reveal distinct features of mitochondrial translation elongation. Nat Commun 2020; 11:3830. [PMID: 32737313 PMCID: PMC7395135 DOI: 10.1038/s41467-020-17715-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 07/15/2020] [Indexed: 02/06/2023] Open
Abstract
The mammalian mitochondrial ribosome (mitoribosome) and its associated translational factors have evolved to accommodate greater participation of proteins in mitochondrial translation. Here we present the 2.68-3.96 Å cryo-EM structures of the human 55S mitoribosome in complex with the human mitochondrial elongation factor G1 (EF-G1mt) in three distinct conformational states, including an intermediate state and a post-translocational state. These structures reveal the role of several mitochondria-specific (mito-specific) mitoribosomal proteins (MRPs) and a mito-specific segment of EF-G1mt in mitochondrial tRNA (tRNAmt) translocation. In particular, the mito-specific C-terminal extension in EF-G1mt is directly involved in translocation of the acceptor arm of the A-site tRNAmt. In addition to the ratchet-like and independent head-swiveling motions exhibited by the small mitoribosomal subunit, we discover significant conformational changes in MRP mL45 at the nascent polypeptide-exit site within the large mitoribosomal subunit that could be critical for tethering of the elongating mitoribosome onto the inner-mitochondrial membrane.
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MESH Headings
- Amino Acid Sequence
- Binding Sites
- Cryoelectron Microscopy
- HEK293 Cells
- Humans
- Mitochondria/metabolism
- Mitochondria/ultrastructure
- Mitochondrial Membranes/metabolism
- Mitochondrial Membranes/ultrastructure
- Mitochondrial Proteins/chemistry
- Mitochondrial Proteins/genetics
- Mitochondrial Proteins/metabolism
- Models, Molecular
- Nucleic Acid Conformation
- Peptide Chain Elongation, Translational
- Peptide Elongation Factor G/chemistry
- Peptide Elongation Factor G/genetics
- Peptide Elongation Factor G/metabolism
- Protein Binding
- Protein Conformation, alpha-Helical
- Protein Conformation, beta-Strand
- Protein Interaction Domains and Motifs
- RNA, Mitochondrial/chemistry
- RNA, Mitochondrial/genetics
- RNA, Mitochondrial/metabolism
- RNA, Transfer/chemistry
- RNA, Transfer/genetics
- RNA, Transfer/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Ribosomal Proteins/chemistry
- Ribosomal Proteins/genetics
- Ribosomal Proteins/metabolism
- Ribosomes/metabolism
- Ribosomes/ultrastructure
- Sequence Alignment
- Sequence Homology, Amino Acid
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Affiliation(s)
- Ravi Kiran Koripella
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA
| | - Manjuli R Sharma
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA
| | - Kalpana Bhargava
- Department of Chemistry, Campus Box 3290, University of North Carolina, Chapel Hill, NC, USA
- High Energy Material Research Lab, Defense Research and Development Organization, Sutarwadi, Pashan, Pune, Maharashtra, 411021, India
| | - Partha P Datta
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, 741246, India
| | - Prem S Kaushal
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA
- Regional Centre for Biotechnology, 3rd Milestone, Faridabad-Gurgaon Expressway, PO Box # 3, Faridabad, Haryana, 121001, India
| | - Pooja Keshavan
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA
| | - Linda L Spremulli
- Department of Chemistry, Campus Box 3290, University of North Carolina, Chapel Hill, NC, USA
| | - Nilesh K Banavali
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY, 12201-0509, USA
| | - Rajendra K Agrawal
- Division of Translational Medicine, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY, 12201, USA.
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY, 12201-0509, USA.
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Keerthiraju E, Du C, Tucker G, Greetham D. A Role for COX20 in Tolerance to Oxidative Stress and Programmed Cell Death in Saccharomyces cerevisiae. Microorganisms 2019; 7:microorganisms7110575. [PMID: 31752220 PMCID: PMC6920987 DOI: 10.3390/microorganisms7110575] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 11/28/2022] Open
Abstract
Industrial production of bioethanol from lignocellulosic materials (LCM′s) is reliant on a microorganism being tolerant to the stresses inherent to fermentation. Previous work has highlighted the importance of a cytochrome oxidase chaperone gene (COX20) in improving yeast tolerance to acetic acid, a common inhibitory compound produced during pre-treatment of LCM’s. The presence of acetic acid has been shown to induce oxidative stress and programmed cell death, so the role of COX20 in oxidative stress was determined. Analysis using flow cytometry revealed that COX20 expression was associated with reduced levels of reactive oxygen species (ROS) in hydrogen peroxide and metal-induced stress, and there was a reduction in apoptotic and necrotic cells when compared with a strain without COX20. Results on the functionality of COX20 have revealed that overexpression of COX20 induced respiratory growth in Δimp1 and Δcox18, two genes whose presence is essential for yeast respiratory growth. COX20 also has a role in protecting the yeast cell against programmed cell death.
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Affiliation(s)
- Ethiraju Keerthiraju
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK; (E.K.); (G.T.)
| | - Chenyu Du
- School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, UK;
| | - Gregory Tucker
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK; (E.K.); (G.T.)
| | - Darren Greetham
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK; (E.K.); (G.T.)
- School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, UK;
- Correspondence: ; Tel.: +44-1484-472378
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10
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Biochemistry of Copper Site Assembly in Heme-Copper Oxidases: A Theme with Variations. Int J Mol Sci 2019; 20:ijms20153830. [PMID: 31387303 PMCID: PMC6696091 DOI: 10.3390/ijms20153830] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 01/18/2023] Open
Abstract
Copper is an essential cofactor for aerobic respiration, since it is required as a redox cofactor in Cytochrome c Oxidase (COX). This ancient and highly conserved enzymatic complex from the family of heme-copper oxidase possesses two copper sites: CuA and CuB. Biosynthesis of the oxidase is a complex, stepwise process that requires a high number of assembly factors. In this review, we summarize the state-of-the-art in the assembly of COX, with special emphasis in the assembly of copper sites. Assembly of the CuA site is better understood, being at the same time highly variable among organisms. We also discuss the current challenges that prevent the full comprehension of the mechanisms of assembly and the pending issues in the field.
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11
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Cogliati S, Lorenzi I, Rigoni G, Caicci F, Soriano ME. Regulation of Mitochondrial Electron Transport Chain Assembly. J Mol Biol 2018; 430:4849-4873. [DOI: 10.1016/j.jmb.2018.09.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/20/2018] [Accepted: 09/25/2018] [Indexed: 12/26/2022]
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12
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Möller-Hergt BV, Carlström A, Stephan K, Imhof A, Ott M. The ribosome receptors Mrx15 and Mba1 jointly organize cotranslational insertion and protein biogenesis in mitochondria. Mol Biol Cell 2018; 29:2386-2396. [PMID: 30091672 PMCID: PMC6233058 DOI: 10.1091/mbc.e18-04-0227] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Mitochondrial gene expression in Saccharomyces cerevisiae is responsible for the production of highly hydrophobic subunits of the oxidative phosphorylation system. Membrane insertion occurs cotranslationally on membrane-bound mitochondrial ribosomes. Here, by employing a systematic mass spectrometry–based approach, we discovered the previously uncharacterized membrane protein Mrx15 that interacts via a soluble C-terminal domain with the large ribosomal subunit. Mrx15 contacts mitochondrial translation products during their synthesis and plays, together with the ribosome receptor Mba1, an overlapping role in cotranslational protein insertion. Taken together, our data reveal how these ribosome receptors organize membrane protein biogenesis in mitochondria.
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Affiliation(s)
| | - Andreas Carlström
- Department of Biochemistry and Biophysics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Katharina Stephan
- Department of Biochemistry and Biophysics, Stockholm University, SE-10691 Stockholm, Sweden
| | - Axel Imhof
- Protein Analysis Unit, Biomedical Center, Faculty of Medicine, Ludwig Maximilian University of Munich, DE-82152 Planegg-Martinsried, Germany
| | - Martin Ott
- Department of Biochemistry and Biophysics, Stockholm University, SE-10691 Stockholm, Sweden
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13
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Kolli R, Soll J, Carrie C. Plant Mitochondrial Inner Membrane Protein Insertion. Int J Mol Sci 2018; 19:E641. [PMID: 29495281 PMCID: PMC5855863 DOI: 10.3390/ijms19020641] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 02/20/2018] [Accepted: 02/22/2018] [Indexed: 02/06/2023] Open
Abstract
During the biogenesis of the mitochondrial inner membrane, most nuclear-encoded inner membrane proteins are laterally released into the membrane by the TIM23 and the TIM22 machinery during their import into mitochondria. A subset of nuclear-encoded mitochondrial inner membrane proteins and all the mitochondrial-encoded inner membrane proteins use the Oxa machinery-which is evolutionarily conserved from the endosymbiotic bacterial ancestor of mitochondria-for membrane insertion. Compared to the mitochondria from other eukaryotes, plant mitochondria have several unique features, such as a larger genome and a branched electron transport pathway, and are also involved in additional cellular functions such as photorespiration and stress perception. This review focuses on the unique aspects of plant mitochondrial inner membrane protein insertion machinery, which differs from that in yeast and humans, and includes a case study on the biogenesis of Cox2 in yeast, humans, two plant species, and an algal species to highlight lineage-specific similarities and differences. Interestingly, unlike mitochondria of other eukaryotes but similar to bacteria and chloroplasts, plant mitochondria appear to use the Tat machinery for membrane insertion of the Rieske Fe/S protein.
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Affiliation(s)
- Renuka Kolli
- Department of Biology I, Botany, Ludwig-Maximilians-Universität München, Großhaderner Strasse 2-4, D-82152 Planegg-Martinsried, Germany.
| | - Jürgen Soll
- Department of Biology I, Botany, Ludwig-Maximilians-Universität München, Großhaderner Strasse 2-4, D-82152 Planegg-Martinsried, Germany.
- Munich Center for Integrated Protein Science, CiPSM, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, D-81377 Munich, Germany.
| | - Chris Carrie
- Department of Biology I, Botany, Ludwig-Maximilians-Universität München, Großhaderner Strasse 2-4, D-82152 Planegg-Martinsried, Germany.
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14
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Lorenzi I, Oeljeklaus S, Aich A, Ronsör C, Callegari S, Dudek J, Warscheid B, Dennerlein S, Rehling P. The mitochondrial TMEM177 associates with COX20 during COX2 biogenesis. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2018; 1865:323-333. [PMID: 29154948 PMCID: PMC5764226 DOI: 10.1016/j.bbamcr.2017.11.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/10/2017] [Accepted: 11/14/2017] [Indexed: 12/17/2022]
Abstract
The three mitochondrial-encoded proteins, COX1, COX2, and COX3, form the core of the cytochrome c oxidase. Upon synthesis, COX2 engages with COX20 in the inner mitochondrial membrane, a scaffold protein that recruits metallochaperones for copper delivery to the CuA-Site of COX2. Here we identified the human protein, TMEM177 as a constituent of the COX20 interaction network. Loss or increase in the amount of TMEM177 affects COX20 abundance leading to reduced or increased COX20 levels respectively. TMEM177 associates with newly synthesized COX2 and SCO2 in a COX20-dependent manner. Our data shows that by unbalancing the amount of TMEM177, newly synthesized COX2 accumulates in a COX20-associated state. We conclude that TMEM177 promotes assembly of COX2 at the level of CuA-site formation.
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Affiliation(s)
- Isotta Lorenzi
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany
| | - Silke Oeljeklaus
- Faculty of Biology, Department of Biochemistry and Functional Proteomics, University Freiburg, D-79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
| | - Abhishek Aich
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany
| | - Christin Ronsör
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany
| | - Sylvie Callegari
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany
| | - Jan Dudek
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany
| | - Bettina Warscheid
- Faculty of Biology, Department of Biochemistry and Functional Proteomics, University Freiburg, D-79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
| | - Sven Dennerlein
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany.
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, D-37073 Göttingen, Germany; Max Planck Institute for Biophysical Chemistry, D-37077 Göttingen, Germany.
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15
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Jett KA, Leary SC. Building the Cu A site of cytochrome c oxidase: A complicated, redox-dependent process driven by a surprisingly large complement of accessory proteins. J Biol Chem 2017; 293:4644-4652. [PMID: 28972150 DOI: 10.1074/jbc.r117.816132] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cytochrome c oxidase (COX) was initially purified more than 70 years ago. A tremendous amount of insight into its structure and function has since been gleaned from biochemical, biophysical, genetic, and molecular studies. As a result, we now appreciate that COX relies on its redox-active metal centers (heme a and a3, CuA and CuB) to reduce oxygen and pump protons in a reaction essential for most eukaryotic life. Questions persist, however, about how individual structural subunits are assembled into a functional holoenzyme. Here, we focus on what is known and what remains to be learned about the accessory proteins that facilitate CuA site maturation.
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Affiliation(s)
- Kimberly A Jett
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Scot C Leary
- Department of Biochemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
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16
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Englmeier R, Pfeffer S, Förster F. Structure of the Human Mitochondrial Ribosome Studied In Situ by Cryoelectron Tomography. Structure 2017; 25:1574-1581.e2. [PMID: 28867615 DOI: 10.1016/j.str.2017.07.011] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/12/2017] [Accepted: 07/26/2017] [Indexed: 01/26/2023]
Abstract
Mitochondria maintain their own genome and its corresponding protein synthesis machine, the mitochondrial ribosome (mitoribosome). Mitoribosomes primarily synthesize highly hydrophobic proteins of the inner mitochondrial membrane. Recent studies revealed the complete structure of the isolated mammalian mitoribosome, but its mode of membrane association remained hypothetical. In this study, we used cryoelectron tomography to visualize human mitoribosomes in isolated mitochondria. The subtomogram average of the membrane-associated human mitoribosome reveals a single major contact site with the inner membrane, mediated by the mitochondria-specific protein mL45. A second rRNA-mediated contact site that is present in yeast is absent in humans, resulting in a more variable association of the human mitoribosome with the inner membrane. Despite extensive structural differences of mammalian and fungal mitoribosomal structure, the principal organization of peptide exit tunnel and the mL45 homolog remains invariant, presumably to align the mitoribosome with the membrane-embedded insertion machinery.
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Affiliation(s)
- Robert Englmeier
- Cryo-Electron Microscopy, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Stefan Pfeffer
- Max-Planck Institute of Biochemistry, Department of Molecular Structural Biology, 82152 Martinsried, Germany
| | - Friedrich Förster
- Cryo-Electron Microscopy, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands; Max-Planck Institute of Biochemistry, Department of Molecular Structural Biology, 82152 Martinsried, Germany.
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17
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Richter-Dennerlein R, Oeljeklaus S, Lorenzi I, Ronsör C, Bareth B, Schendzielorz AB, Wang C, Warscheid B, Rehling P, Dennerlein S. Mitochondrial Protein Synthesis Adapts to Influx of Nuclear-Encoded Protein. Cell 2016; 167:471-483.e10. [PMID: 27693358 PMCID: PMC5055049 DOI: 10.1016/j.cell.2016.09.003] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 08/01/2016] [Accepted: 08/30/2016] [Indexed: 12/11/2022]
Abstract
Mitochondrial ribosomes translate membrane integral core subunits of the oxidative phosphorylation system encoded by mtDNA. These translation products associate with nuclear-encoded, imported proteins to form enzyme complexes that produce ATP. Here, we show that human mitochondrial ribosomes display translational plasticity to cope with the supply of imported nuclear-encoded subunits. Ribosomes expressing mitochondrial-encoded COX1 mRNA selectively engage with cytochrome c oxidase assembly factors in the inner membrane. Assembly defects of the cytochrome c oxidase arrest mitochondrial translation in a ribosome nascent chain complex with a partially membrane-inserted COX1 translation product. This complex represents a primed state of the translation product that can be retrieved for assembly. These findings establish a mammalian translational plasticity pathway in mitochondria that enables adaptation of mitochondrial protein synthesis to the influx of nuclear-encoded subunits. Mitochondrial ribosomes display translational plasticity COX1 translation in mitochondria is stalled in the absence of nuclear-encoded COX4 A ribosome nascent chain complex of COX1 is a primed state for complex IV assembly MITRAC regulates translation via COX1 ribosome nascent chain complexes interaction
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Affiliation(s)
- Ricarda Richter-Dennerlein
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany
| | - Silke Oeljeklaus
- Department of Biochemistry and Functional Proteomics, Faculty of Biology, University Freiburg, 79104 Freiburg, Germany
| | - Isotta Lorenzi
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany
| | - Christin Ronsör
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany
| | - Bettina Bareth
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany
| | | | - Cong Wang
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany
| | - Bettina Warscheid
- Department of Biochemistry and Functional Proteomics, Faculty of Biology, University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany; Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany.
| | - Sven Dennerlein
- Department of Cellular Biochemistry, University Medical Centre Göttingen, GZMB, 37073 Göttingen, Germany
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