1
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Maruszczak KK, Draczkowski P, Wnorowski A, Chacinska A. Structure prediction analysis of human core TIM23 complex reveals conservation of the protein translocation mechanism. FEBS Open Bio 2024. [PMID: 38837610 DOI: 10.1002/2211-5463.13840] [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: 04/17/2024] [Revised: 05/21/2024] [Accepted: 05/27/2024] [Indexed: 06/07/2024] Open
Abstract
The majority of mitochondrial proteins are encoded in the nucleus, translated on cytosolic ribosomes, and subsequently targeted to the mitochondrial surface. Their further import into the organelle is facilitated by highly specialized protein translocases. Mitochondrial precursor proteins that are destined to the mitochondrial matrix and, to some extent, the inner membrane, utilize translocase of the inner membrane (TIM23). This indispensable import machinery has been extensively studied in yeast. The translocating unit of the TIM23 complex in yeast consists of two membrane proteins, Tim17 and Tim23. In contrast to previous findings, recent reports demonstrate the primary role of Tim17, rather than Tim23, in the translocation of newly synthesized proteins. Very little is known about human TIM23 translocase. Human cells have two orthologs of yeast Tim17, TIMM17A and TIMM17B. Here, using computational tools, we present the architecture of human core TIM23 variants with either TIMM17A or TIMM17B, forming two populations of highly similar complexes. The structures reveal high conservation of the core TIM23 complex between human and yeast. Interestingly, both TIMM17A and TIMM17B variants interact with TIMM23 and reactive oxygen species modulator 1 (ROMO1); a homolog of yeast Mgr2, a protein that can create a channel-like structure with Tim17. The high structural conservation of proteins that form the core TIM23 complex in yeast and humans raises an interesting question about mechanistic and functional differences that justify existence of the two variants of TIM23 in higher eukaryotes.
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Affiliation(s)
| | - Piotr Draczkowski
- National Bioinformatics Infrastructure Sweden, SciLifeLab, Solna, Sweden
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Medical University of Lublin, Poland
| | - Artur Wnorowski
- Department of Biopharmacy, Medical University of Lublin, Poland
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2
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Hoogstraten CA, Schirris TJJ, Russel FGM. Unlocking mitochondrial drug targets: The importance of mitochondrial transport proteins. Acta Physiol (Oxf) 2024; 240:e14150. [PMID: 38666512 DOI: 10.1111/apha.14150] [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: 10/04/2023] [Revised: 03/02/2024] [Accepted: 04/12/2024] [Indexed: 05/12/2024]
Abstract
A disturbed mitochondrial function contributes to the pathology of many common diseases. These organelles are therefore important therapeutic targets. On the contrary, many adverse effects of drugs can be explained by a mitochondrial off-target effect, in particular, due to an interaction with carrier proteins in the inner membrane. Yet this class of transport proteins remains underappreciated and understudied. The aim of this review is to provide a deeper understanding of the role of mitochondrial carriers in health and disease and their significance as drug targets. We present literature-based evidence that mitochondrial carrier proteins are associated with prevalent diseases and emphasize their potential as drug (off-)target sites by summarizing known mitochondrial drug-transporter interactions. Studying these carriers will enhance our knowledge of mitochondrial drug on- and off-targets and provide opportunities to further improve the efficacy and safety of drugs.
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Affiliation(s)
- Charlotte A Hoogstraten
- Department of Pharmacy, Division of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
- Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom J J Schirris
- Department of Pharmacy, Division of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
- Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Frans G M Russel
- Department of Pharmacy, Division of Pharmacology and Toxicology, Radboud University Medical Center, Nijmegen, the Netherlands
- Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
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3
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von Känel C, Oeljeklaus S, Wenger C, Stettler P, Harsman A, Warscheid B, Schneider A. Intermembrane space-localized TbTim15 is an essential subunit of the single mitochondrial inner membrane protein translocase of trypanosomes. Mol Microbiol 2024; 121:1112-1126. [PMID: 38622999 DOI: 10.1111/mmi.15262] [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: 01/23/2024] [Revised: 03/24/2024] [Accepted: 03/25/2024] [Indexed: 04/17/2024]
Abstract
All mitochondria import >95% of their proteins from the cytosol. This process is mediated by protein translocases in the mitochondrial membranes, whose subunits are generally highly conserved. Most eukaryotes have two inner membrane protein translocases (TIMs) that are specialized to import either presequence-containing or mitochondrial carrier proteins. In contrast, the parasitic protozoan Trypanosoma brucei has a single TIM complex consisting of one conserved and five unique subunits. Here, we identify candidates for new subunits of the TIM or the presequence translocase-associated motor (PAM) using a protein-protein interaction network of previously characterized TIM and PAM subunits. This analysis reveals that the trypanosomal TIM complex contains an additional trypanosomatid-specific subunit, designated TbTim15. TbTim15 is associated with the TIM complex, lacks transmembrane domains, and localizes to the intermembrane space. TbTim15 is essential for procyclic and bloodstream forms of trypanosomes. It contains two twin CX9C motifs and mediates import of both presequence-containing and mitochondrial carrier proteins. While the precise function of TbTim15 in mitochondrial protein import is unknown, our results are consistent with the notion that it may function as an import receptor for the non-canonical trypanosomal TIM complex.
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Affiliation(s)
- Corinne von Känel
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Silke Oeljeklaus
- Faculty of Chemistry and Pharmacy, Biochemistry II, Theodor Boveri-Institute, University of Würzburg, Würzburg, Germany
| | - Christoph Wenger
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Philip Stettler
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Anke Harsman
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
| | - Bettina Warscheid
- Faculty of Chemistry and Pharmacy, Biochemistry II, Theodor Boveri-Institute, University of Würzburg, Würzburg, Germany
| | - André Schneider
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Bern, Switzerland
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4
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Genge MG, Roy Chowdhury S, Dohnálek V, Yunoki K, Hirashima T, Endo T, Doležal P, Mokranjac D. Two domains of Tim50 coordinate translocation of proteins across the two mitochondrial membranes. Life Sci Alliance 2023; 6:e202302122. [PMID: 37748811 PMCID: PMC10520260 DOI: 10.26508/lsa.202302122] [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: 04/28/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 09/27/2023] Open
Abstract
Hundreds of mitochondrial proteins with N-terminal presequences are translocated across the outer and inner mitochondrial membranes via the TOM and TIM23 complexes, respectively. How translocation of proteins across two mitochondrial membranes is coordinated is largely unknown. Here, we show that the two domains of Tim50 in the intermembrane space, named core and PBD, both have essential roles in this process. Building upon the surprising observation that the two domains of Tim50 can complement each other in trans, we establish that the core domain contains the main presequence-binding site and serves as the main recruitment point to the TIM23 complex. On the other hand, the PBD plays, directly or indirectly, a critical role in cooperation of the TOM and TIM23 complexes and supports the receptor function of Tim50. Thus, the two domains of Tim50 both have essential but distinct roles and together coordinate translocation of proteins across two mitochondrial membranes.
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Affiliation(s)
- Marcel G Genge
- Biocenter-Department of Cell Biology, LMU Munich, Munich, Germany
| | | | - Vít Dohnálek
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Kaori Yunoki
- Faculty of Life Sciences and Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto, Japan
| | - Takashi Hirashima
- Faculty of Life Sciences and Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto, Japan
| | - Toshiya Endo
- Faculty of Life Sciences and Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto, Japan
| | - Pavel Doležal
- Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Dejana Mokranjac
- Biocenter-Department of Cell Biology, LMU Munich, Munich, Germany
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5
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Wasilewski M, Draczkowski P, Chacinska A. Protein import into mitochondria - a new path through the membranes. Nat Struct Mol Biol 2023; 30:1831-1833. [PMID: 38087086 DOI: 10.1038/s41594-023-01170-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Affiliation(s)
| | - Piotr Draczkowski
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances, Faculty of Pharmacy, Medical University of Lublin, Lublin, Poland
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6
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Fielden LF, Busch JD, Merkt SG, Ganesan I, Steiert C, Hasselblatt HB, Busto JV, Wirth C, Zufall N, Jungbluth S, Noll K, Dung JM, Butenko L, von der Malsburg K, Koch HG, Hunte C, van der Laan M, Wiedemann N. Central role of Tim17 in mitochondrial presequence protein translocation. Nature 2023; 621:627-634. [PMID: 37527780 PMCID: PMC10511324 DOI: 10.1038/s41586-023-06477-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 07/25/2023] [Indexed: 08/03/2023]
Abstract
The presequence translocase of the mitochondrial inner membrane (TIM23) represents the major route for the import of nuclear-encoded proteins into mitochondria1,2. About 60% of more than 1,000 different mitochondrial proteins are synthesized with amino-terminal targeting signals, termed presequences, which form positively charged amphiphilic α-helices3,4. TIM23 sorts the presequence proteins into the inner membrane or matrix. Various views, including regulatory and coupling functions, have been reported on the essential TIM23 subunit Tim17 (refs. 5-7). Here we mapped the interaction of Tim17 with matrix-targeted and inner membrane-sorted preproteins during translocation in the native membrane environment. We show that Tim17 contains conserved negative charges close to the intermembrane space side of the bilayer, which are essential to initiate presequence protein translocation along a distinct transmembrane cavity of Tim17 for both classes of preproteins. The amphiphilic character of mitochondrial presequences directly matches this Tim17-dependent translocation mechanism. This mechanism permits direct lateral release of transmembrane segments of inner membrane-sorted precursors into the inner membrane.
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Affiliation(s)
- Laura F Fielden
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jakob D Busch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sandra G Merkt
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Iniyan Ganesan
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Conny Steiert
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Hanna B Hasselblatt
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jon V Busto
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christophe Wirth
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Nicole Zufall
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sibylle Jungbluth
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Saarland University, Homburg, Germany
| | - Katja Noll
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Saarland University, Homburg, Germany
| | - Julia M Dung
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ludmila Butenko
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Karina von der Malsburg
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Saarland University, Homburg, Germany
| | - Hans-Georg Koch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Carola Hunte
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- BIOSS-Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Martin van der Laan
- Medical Biochemistry and Molecular Biology, Center for Molecular Signaling, PZMS, Saarland University, Homburg, Germany.
| | - Nils Wiedemann
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
- BIOSS-Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
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7
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Homberg B, Rehling P, Cruz-Zaragoza LD. The multifaceted mitochondrial OXA insertase. Trends Cell Biol 2023; 33:765-772. [PMID: 36863885 DOI: 10.1016/j.tcb.2023.02.001] [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: 11/17/2022] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 03/04/2023]
Abstract
Most mitochondrial proteins are synthesized in the cytosol and transported into mitochondria by protein translocases. Yet, mitochondria contain their own genome and gene expression system, which generates proteins that are inserted in the inner membrane by the oxidase assembly (OXA) insertase. OXA contributes to targeting proteins from both genetic origins. Recent data provides insights into how OXA cooperates with the mitochondrial ribosome during synthesis of mitochondrial-encoded proteins. A picture of OXA emerges in which it coordinates insertion of OXPHOS core subunits and their assembly into protein complexes but also participates in the biogenesis of select imported proteins. These functions position the OXA as a multifunctional protein insertase that facilitates protein transport, assembly, and stability at the inner membrane.
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Affiliation(s)
- Bettina Homberg
- Department of Cellular Biochemistry, University Medical Center Göttingen, 37073 Göttingen, Germany
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Center Göttingen, 37073 Göttingen, Germany; Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), 37073 University of Göttingen, Germany; Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Translational Neuroinflammation and Automated Microscopy TNM, 37075 Göttingen, Germany; Max Planck Institute for Multidisciplinary Science, 37077 Göttingen, Germany.
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8
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Makki A, Rehling P. Protein transport along the presequence pathway. Biol Chem 2023; 404:807-812. [PMID: 37155927 DOI: 10.1515/hsz-2023-0133] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 04/25/2023] [Indexed: 05/10/2023]
Abstract
Most mitochondrial proteins are nuclear-encoded and imported by the protein import machinery based on specific targeting signals. The proteins that carry an amino-terminal targeting signal (presequence) are imported via the presequence import pathway that involves the translocases of the outer and inner membranes - TOM and TIM23 complexes. In this article, we discuss how mitochondrial matrix and inner membrane precursor proteins are imported along the presequence pathway in Saccharomyces cerevisiae with a focus on the dynamics of the TIM23 complex, and further update with some of the key findings that advanced the field in the last few years.
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Affiliation(s)
- Abhijith Makki
- Department of Cellular Biochemistry, University Medical Center Göttingen, D-37073 Göttingen, Germany
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Center Göttingen, D-37073 Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany
- Max Planck Institute for Multidisciplinary Sciences, D-37077 Göttingen, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Translational Neuroinflammation and Automated Microscopy, Göttingen, Germany
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9
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Peker E, Weiss K, Song J, Zarges C, Gerlich S, Boehm V, Trifunovic A, Langer T, Gehring NH, Becker T, Riemer J. A two-step mitochondrial import pathway couples the disulfide relay with matrix complex I biogenesis. J Cell Biol 2023; 222:e202210019. [PMID: 37159021 PMCID: PMC10174193 DOI: 10.1083/jcb.202210019] [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: 10/05/2022] [Revised: 03/03/2023] [Accepted: 04/06/2023] [Indexed: 05/10/2023] Open
Abstract
Mitochondria critically rely on protein import and its tight regulation. Here, we found that the complex I assembly factor NDUFAF8 follows a two-step import pathway linking IMS and matrix import systems. A weak targeting sequence drives TIM23-dependent NDUFAF8 matrix import, and en route, allows exposure to the IMS disulfide relay, which oxidizes NDUFAF8. Import is closely surveyed by proteases: YME1L prevents accumulation of excess NDUFAF8 in the IMS, while CLPP degrades reduced NDUFAF8 in the matrix. Therefore, NDUFAF8 can only fulfil its function in complex I biogenesis if both oxidation in the IMS and subsequent matrix import work efficiently. We propose that the two-step import pathway for NDUFAF8 allows integration of the activity of matrix complex I biogenesis pathways with the activity of the mitochondrial disulfide relay system in the IMS. Such coordination might not be limited to NDUFAF8 as we identified further proteins that can follow such a two-step import pathway.
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Affiliation(s)
- Esra Peker
- Institute for Biochemistry, University of Cologne, Cologne, Germany
| | - Konstantin Weiss
- Institute for Biochemistry, University of Cologne, Cologne, Germany
| | - Jiyao Song
- Institute of Biochemistry and Molecular Biology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Christine Zarges
- Institute for Biochemistry, University of Cologne, Cologne, Germany
| | - Sarah Gerlich
- Institute for Biochemistry, University of Cologne, Cologne, Germany
| | - Volker Boehm
- Institute for Genetics, University of Cologne, Cologne, Germany
| | - Aleksandra Trifunovic
- Institute for Mitochondrial Diseases and Aging, Medical Faculty, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Thomas Langer
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine, University of Cologne, Cologne, Germany
- Department of Mitochondrial Proteostasis, Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Niels H. Gehring
- Institute for Genetics, University of Cologne, Cologne, Germany
- Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Jan Riemer
- Institute for Biochemistry, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
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10
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Liang HZ, Lu PX, Chu LL, Li G, Li CB, Chen XJ, Zhang J, Song J, Zhang T, Luo Y, Hu Y, Ma BP. Dammarane-type saponins from Gynostemma pentaphyllum and their anti-aging activities via up-regulating mitochondria related proteins. PHYTOCHEMISTRY 2023:113744. [PMID: 37301356 DOI: 10.1016/j.phytochem.2023.113744] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 05/24/2023] [Accepted: 05/28/2023] [Indexed: 06/12/2023]
Abstract
The importance of mitochondria in regulation of aging has been extensively recognized and confirmed. Gynostemma pentaphyllum (Thunb.) Makino, a homology of medicine and food, has been widely utilized as dietary supplement. In this study, the transcriptome of normal cells (wild type mouse embryo fibroblasts) regulated by the 30% aqueous EtOH extract of G. pentaphyllum was firstly evaluated by RNA sequencing and the results revealed that the G. pentaphyllum could up-regulate the genes involved in oxidative phosphorylation (OXPHOS) and sirtuin (SIRT) signaling pathways, indicating its effect in promoting cell viability might be attributed to the role of improving mitochondrial functions. To further discover the bioactive compounds, sixteen undescribed dammarane-type saponins along with twenty-eight known analogues were isolated from the active extract of G. pentaphyllum. Their structures were elucidated by means of comprehensive analysis of NMR and HRMS spectroscopic data. All isolates were evaluated for the regulatory effects on SIRT3 and translocase of the outer membrane 20 (TOM20), and thirteen of them exhibited satisfactory agonist activities on both SIRT3 and TOM20 at 5 μM. Furthermore, the preliminary structure-activity relationships analysis demonstrated the additional hydroxymethyl and carbonyl groups or less sugar residues in saponins could contribute positively to the up-regulatory effect on SIRT3 and TOM20. These findings encouraged the potential roles of G. pentaphyllum and its bioactive saponins in the development of natural drugs for the treatment of aging-related diseases.
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Affiliation(s)
- Hai-Zhen Liang
- Beijing Institute of Radiation Medicine, Beijing, 100850, China
| | - Peng-Xin Lu
- Beijing Institute of Radiation Medicine, Beijing, 100850, China
| | - Li-Li Chu
- School of Basic Medicine, Guizhou Medical University, Guizhou, 550025, China
| | - Gang Li
- Beijing Institute of Radiation Medicine, Beijing, 100850, China
| | - Chuan-Biao Li
- School of Basic Medicine, Guizhou Medical University, Guizhou, 550025, China
| | - Xiao-Juan Chen
- Beijing Institute of Radiation Medicine, Beijing, 100850, China
| | - Jie Zhang
- Beijing Institute of Radiation Medicine, Beijing, 100850, China
| | - Juan Song
- Beijing Institute of Radiation Medicine, Beijing, 100850, China
| | - Tao Zhang
- AnKang Chia Tai Pharmaceutical Co. Ltd., Shaanxi, 725000, China
| | - Ying Luo
- School of Basic Medicine, Guizhou Medical University, Guizhou, 550025, China
| | - Ying Hu
- School of Basic Medicine, Guizhou Medical University, Guizhou, 550025, China.
| | - Bai-Ping Ma
- Beijing Institute of Radiation Medicine, Beijing, 100850, China.
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11
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Jain N, Gomkale R, Bernhard O, Rehling P, Cruz-Zaragoza LD. A quantitative fluorescence-based approach to study mitochondrial protein import. EMBO Rep 2023; 24:e55760. [PMID: 36938994 PMCID: PMC10157374 DOI: 10.15252/embr.202255760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 01/22/2023] [Accepted: 02/17/2023] [Indexed: 03/21/2023] Open
Abstract
Mitochondria play central roles in cellular energy production and metabolism. Most proteins required to carry out these functions are synthesized in the cytosol and imported into mitochondria. A growing number of metabolic disorders arising from mitochondrial dysfunction can be traced to errors in mitochondrial protein import. The mechanisms underlying the import of precursor proteins are commonly studied using radioactively labeled precursor proteins imported into purified mitochondria. Here, we establish a fluorescence-based import assay to analyze protein import into mitochondria. We show that fluorescently labeled precursors enable import analysis with similar sensitivity to those using radioactive precursors, yet they provide the advantage of quantifying import with picomole resolution. We adapted the import assay to a 96-well plate format allowing for fast analysis in a screening-compatible format. Moreover, we show that fluorescently labeled precursors can be used to monitor the assembly of the F1 F0 ATP synthase in purified mitochondria. Thus, we provide a sensitive fluorescence-based import assay that enables quantitative and fast import analysis.
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Affiliation(s)
- Naintara Jain
- Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Ridhima Gomkale
- Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Olaf Bernhard
- Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany.,Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany.,Max Planck Institute for Multidisciplinary Science, Göttingen, Germany
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12
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Rosenkranz AA, Slastnikova TA. Prospects of Using Protein Engineering for Selective Drug Delivery into a Specific Compartment of Target Cells. Pharmaceutics 2023; 15:pharmaceutics15030987. [PMID: 36986848 PMCID: PMC10055131 DOI: 10.3390/pharmaceutics15030987] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 03/13/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
A large number of proteins are successfully used to treat various diseases. These include natural polypeptide hormones, their synthetic analogues, antibodies, antibody mimetics, enzymes, and other drugs based on them. Many of them are demanded in clinical settings and commercially successful, mainly for cancer treatment. The targets for most of the aforementioned drugs are located at the cell surface. Meanwhile, the vast majority of therapeutic targets, which are usually regulatory macromolecules, are located inside the cell. Traditional low molecular weight drugs freely penetrate all cells, causing side effects in non-target cells. In addition, it is often difficult to elaborate a small molecule that can specifically affect protein interactions. Modern technologies make it possible to obtain proteins capable of interacting with almost any target. However, proteins, like other macromolecules, cannot, as a rule, freely penetrate into the desired cellular compartment. Recent studies allow us to design multifunctional proteins that solve these problems. This review considers the scope of application of such artificial constructs for the targeted delivery of both protein-based and traditional low molecular weight drugs, the obstacles met on the way of their transport to the specified intracellular compartment of the target cells after their systemic bloodstream administration, and the means to overcome those difficulties.
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Affiliation(s)
- Andrey A Rosenkranz
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology of Russian Academy of Sciences, 34/5 Vavilov St., 119334 Moscow, Russia
- Department of Biophysics, Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory St., 119234 Moscow, Russia
| | - Tatiana A Slastnikova
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology of Russian Academy of Sciences, 34/5 Vavilov St., 119334 Moscow, Russia
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13
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Sohrabi T, Mirzaei-Behbahani B, Zadali R, Pirhaghi M, Morozova-Roche LA, Meratan AA. Common Mechanisms Underlying α-Synuclein-Induced Mitochondrial Dysfunction in Parkinson's Disease. J Mol Biol 2023:167992. [PMID: 36736886 DOI: 10.1016/j.jmb.2023.167992] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/19/2023] [Accepted: 01/24/2023] [Indexed: 02/05/2023]
Abstract
Parkinson's disease (PD) is the most common neurological movement disorder characterized by the selective and irreversible loss of dopaminergic neurons in substantia nigra pars compacta resulting in dopamine deficiency in the striatum. While most cases are sporadic or environmental, about 10% of patients have a positive family history with a genetic cause. The misfolding and aggregation of α-synuclein (α-syn) as a casual factor in the pathogenesis of PD has been supported by a great deal of literature. Extensive studies of mechanisms underpinning degeneration of the dopaminergic neurons induced by α-syn dysfunction suggest a complex process that involves multiple pathways, including mitochondrial dysfunction and increased oxidative stress, impaired calcium homeostasis through membrane permeabilization, synaptic dysfunction, impairment of quality control systems, disruption of microtubule dynamics and axonal transport, endoplasmic reticulum/Golgi dysfunction, nucleus malfunction, and microglia activation leading to neuroinflammation. Among them mitochondrial dysfunction has been considered as the most primary target of α-syn-induced toxicity, leading to neuronal cell death in both sporadic and familial forms of PD. Despite reviewing many aspects of PD pathogenesis related to mitochondrial dysfunction, a systemic study on how α-syn malfunction/aggregation damages mitochondrial functionality and leads to neurodegeneration is missing in the literature. In this review, we give a detailed molecular overview of the proposed mechanisms by which α-syn, directly or indirectly, contributes to mitochondrial dysfunction. This may provide valuable insights for development of new therapeutic approaches in relation to PD. Antioxidant-based therapy as a potential strategy to protect mitochondria against oxidative damage, its challenges, and recent developments in the field are discussed.
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Affiliation(s)
- Tahereh Sohrabi
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Behnaz Mirzaei-Behbahani
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Ramin Zadali
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Mitra Pirhaghi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | | | - Ali Akbar Meratan
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.
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14
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Song J, Steidle L, Steymans I, Singh J, Sanner A, Böttinger L, Winter D, Becker T. The mitochondrial Hsp70 controls the assembly of the F 1F O-ATP synthase. Nat Commun 2023; 14:39. [PMID: 36596815 PMCID: PMC9810599 DOI: 10.1038/s41467-022-35720-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 12/20/2022] [Indexed: 01/04/2023] Open
Abstract
The mitochondrial F1FO-ATP synthase produces the bulk of cellular ATP. The soluble F1 domain contains the catalytic head that is linked via the central stalk and the peripheral stalk to the membrane embedded rotor of the FO domain. The assembly of the F1 domain and its linkage to the peripheral stalk is poorly understood. Here we show a dual function of the mitochondrial Hsp70 (mtHsp70) in the formation of the ATP synthase. First, it cooperates with the assembly factors Atp11 and Atp12 to form the F1 domain of the ATP synthase. Second, the chaperone transfers Atp5 into the assembly line to link the catalytic head with the peripheral stalk. Inactivation of mtHsp70 leads to integration of assembly-defective Atp5 variants into the mature complex, reflecting a quality control function of the chaperone. Thus, mtHsp70 acts as an assembly and quality control factor in the biogenesis of the F1FO-ATP synthase.
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Affiliation(s)
- Jiyao Song
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany.,Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Liesa Steidle
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Isabelle Steymans
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Jasjot Singh
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Anne Sanner
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Lena Böttinger
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dominic Winter
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Thomas Becker
- Institute for Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany.
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15
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Gu Y, Guerra F, Hu M, Pope A, Sung K, Yang W, Jetha S, Shoff TA, Gunatilake T, Dahlkamp O, Shi LZ, Manganelli F, Nolano M, Zhou Y, Ding J, Bucci C, Wu C. Mitochondria dysfunction in Charcot Marie Tooth 2B Peripheral Sensory Neuropathy. Commun Biol 2022; 5:717. [PMID: 35851620 PMCID: PMC9293960 DOI: 10.1038/s42003-022-03632-1] [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: 10/12/2021] [Accepted: 06/23/2022] [Indexed: 11/21/2022] Open
Abstract
Rab7 GTPase regulates mitochondrial morphology and function. Missense mutation(s) of Rab7 underlies the pathogenesis of Charcot Marie Tooth 2B (CMT2B) peripheral neuropathy. Herein, we investigate how mitochondrial morphology and function are impacted by the CMT2B associated Rab7V162M mutation. In contrast to recent studies of using heterologous overexpression systems, our results demonstrate significant mitochondrial fragmentation in both human CMT2B patient fibroblasts and CMT2B embryonic fibroblasts (MEFs). Primary cultured E18 dorsal root ganglion (DRG) sensory neurons also show mitochondrial fragmentation and altered axonal mitochondrial movement. In addition, we demonstrate that inhibitors to either the mitochondrial fission protein Drp1 or to the nucleotide binding to Rab7 normalize the mitochondrial deficits in both MEFs and E18 cultured DRG neurons. Our study reveals, for the first time, that expression of CMT2B Rab7 mutation at the physiological level enhances Drp1 activity to promote mitochondrial fission, potentially underlying selective vulnerability of peripheral sensory neurons in CMT2B pathogenesis. The Rab7V162M mutation associated with Charcot Marie Tooth 2B peripheral neuropathy causes mitochondrial fragmentation in patient-derived fibroblasts and primary cultured dorsal root ganglion sensory neurons from E18 mouse embryos.
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Affiliation(s)
- Yingli Gu
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA.,Department of Neurology, the Fourth Hospital of Harbin Medical University, Harbin, 150001, Heilongjiang, China
| | - Flora Guerra
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Università del Salento, Via Provinciale Lecce-Monteroni n. 165, 73100, Lecce, Italy
| | - Mingzheng Hu
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Alexander Pope
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Kijung Sung
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Wanlin Yang
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA.,Department of Neurology, Zhujiang Hospital of Southern Medical University Guangzhou, Guangzhou, 510280, Guangdong Sheng, China
| | - Simone Jetha
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Thomas A Shoff
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Tessanya Gunatilake
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Owen Dahlkamp
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA
| | - Linda Zhixia Shi
- Department of Bioengineering, University of California San Diego, La Jolla, 92093, CA, USA
| | - Fiore Manganelli
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Via Sergio Pansini 5, 80131, Naples, Italy
| | - Maria Nolano
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Via Sergio Pansini 5, 80131, Naples, Italy
| | - Yue Zhou
- School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 200030, China
| | - Jianqing Ding
- Institute of Neurology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Cecilia Bucci
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Università del Salento, Via Provinciale Lecce-Monteroni n. 165, 73100, Lecce, Italy.
| | - Chengbiao Wu
- Department of Neurosciences, University of California San Diego, La Jolla, 92093, CA, USA.
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16
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Hoffmann JJ, Becker T. Crosstalk between Mitochondrial Protein Import and Lipids. Int J Mol Sci 2022; 23:ijms23095274. [PMID: 35563660 PMCID: PMC9101885 DOI: 10.3390/ijms23095274] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 04/29/2022] [Accepted: 05/05/2022] [Indexed: 12/10/2022] Open
Abstract
Mitochondria import about 1000 precursor proteins from the cytosol. The translocase of the outer membrane (TOM complex) forms the major entry site for precursor proteins. Subsequently, membrane-bound protein translocases sort the precursor proteins into the outer and inner membrane, the intermembrane space, and the matrix. The phospholipid composition of mitochondrial membranes is critical for protein import. Structural and biochemical data revealed that phospholipids affect the stability and activity of mitochondrial protein translocases. Integration of proteins into the target membrane involves rearrangement of phospholipids and distortion of the lipid bilayer. Phospholipids are present in the interface between subunits of protein translocases and affect the dynamic coupling of partner proteins. Phospholipids are required for full activity of the respiratory chain to generate membrane potential, which in turn drives protein import across and into the inner membrane. Finally, outer membrane protein translocases are closely linked to organellar contact sites that mediate lipid trafficking. Altogether, intensive crosstalk between mitochondrial protein import and lipid biogenesis controls mitochondrial biogenesis.
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17
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Sayyed UMH, Mahalakshmi R. Mitochondrial protein translocation machinery: From TOM structural biogenesis to functional regulation. J Biol Chem 2022; 298:101870. [PMID: 35346689 PMCID: PMC9052162 DOI: 10.1016/j.jbc.2022.101870] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 03/13/2022] [Accepted: 03/14/2022] [Indexed: 01/15/2023] Open
Abstract
The human mitochondrial outer membrane is biophysically unique as it is the only membrane possessing transmembrane β-barrel proteins (mitochondrial outer membrane proteins, mOMPs) in the cell. The most vital of the three mOMPs is the core protein of the translocase of the outer mitochondrial membrane (TOM) complex. Identified first as MOM38 in Neurospora in 1990, the structure of Tom40, the core 19-stranded β-barrel translocation channel, was solved in 2017, after nearly three decades. Remarkably, the past four years have witnessed an exponential increase in structural and functional studies of yeast and human TOM complexes. In addition to being conserved across all eukaryotes, the TOM complex is the sole ATP-independent import machinery for nearly all of the ∼1000 to 1500 known mitochondrial proteins. Recent cryo-EM structures have provided detailed insight into both possible assembly mechanisms of the TOM core complex and organizational dynamics of the import machinery and now reveal novel regulatory interplay with other mOMPs. Functional characterization of the TOM complex using biochemical and structural approaches has also revealed mechanisms for substrate recognition and at least five defined import pathways for precursor proteins. In this review, we discuss the discovery, recently solved structures, molecular function, and regulation of the TOM complex and its constituents, along with the implications these advances have for alleviating human diseases.
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Affiliation(s)
- Ulfat Mohd Hanif Sayyed
- Molecular Biophysics Laboratory, Indian Institute of Science Education and Research, Bhopal, India
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18
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Priesnitz C, Böttinger L, Zufall N, Gebert M, Guiard B, van der Laan M, Becker T. Coupling to Pam16 differentially controls the dual role of Pam18 in protein import and respiratory chain formation. Cell Rep 2022; 39:110619. [PMID: 35385740 DOI: 10.1016/j.celrep.2022.110619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 01/31/2022] [Accepted: 03/15/2022] [Indexed: 11/03/2022] Open
Abstract
The presequence translocase (TIM23 complex) imports precursor proteins into the mitochondrial inner membrane and matrix. The presequence translocase-associated motor (PAM) provides a driving force for transport into the matrix. The J-protein Pam18 stimulates the ATPase activity of the mitochondrial Hsp70 (mtHsp70). Pam16 recruits Pam18 to the TIM23 complex to ensure protein import. The Pam16-Pam18 module also associates with components of the respiratory chain, but the function of the dual localization of Pam16-Pam18 is largely unknown. Here, we show that disruption of the Pam16-Pam18 heterodimer causes redistribution of Pam18 to the respiratory chain supercomplexes, where it forms a homodimer. Redistribution of Pam18 decreases protein import into mitochondria but stimulates mtHsp70-dependent assembly of respiratory chain complexes. We conclude that coupling to Pam16 differentially controls the dual function of Pam18. It recruits Pam18 to the TIM23 complex to promote protein import but attenuates the Pam18 function in the assembly of respiratory chain complexes.
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Affiliation(s)
- Chantal Priesnitz
- 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
| | - Lena Böttinger
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Nicole Zufall
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Michael Gebert
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, 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.
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19
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Dissecting the molecular mechanisms of mitochondrial import and maturation of peroxiredoxins from yeast and mammalian cells. Biophys Rev 2022; 13:983-994. [PMID: 35059022 DOI: 10.1007/s12551-021-00899-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/01/2021] [Indexed: 12/26/2022] Open
Abstract
Peroxiredoxins (Prxs) are cysteine-based peroxidases that play a central role in keeping the H2O2 at physiological levels. Eukaryotic cells express different Prxs isoforms, which differ in their subcellular locations and substrate specificities. Mitochondrial Prxs are synthesized in the cytosol as precursor proteins containing N-terminal cleavable presequences that act as mitochondrial targeting signals. Due to the fact that presequence controls the import of the vast majority of mitochondrial matrix proteins, the mitochondrial Prxs were initially predicted to be localized exclusively in the matrix. However, recent studies showed that mitochondrial Prxs are also targeted to the intermembrane space by mechanisms that remain poorly understood. While in yeast the IMP complex can translocate Prx1 to the intermembrane space, the maturation of yeast Prx1 and mammalian Prdx3 and Prdx5 in the matrix has been associated with sequential cleavages of the presequence by MPP and Oct1/MIP proteases. In this review, we describe the state of the art of the molecular mechanisms that control the mitochondrial import and maturation of Prxs of yeast and human cells. Once mitochondria are considered the major intracellular source of H2O2, understanding the mitochondrial Prx biogenesis pathways is essential to increase our knowledge about the H2O2-dependent cellular signaling, which is relevant to the pathophysiology of some human diseases.
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20
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Genge MG, Mokranjac D. Coordinated Translocation of Presequence-Containing Precursor Proteins Across Two Mitochondrial Membranes: Knowns and Unknowns of How TOM and TIM23 Complexes Cooperate With Each Other. Front Physiol 2022; 12:806426. [PMID: 35069261 PMCID: PMC8770809 DOI: 10.3389/fphys.2021.806426] [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: 10/31/2021] [Accepted: 12/03/2021] [Indexed: 11/23/2022] Open
Abstract
The vast majority of mitochondrial proteins are encoded in the nuclear genome and synthesized on cytosolic ribosomes as precursor proteins with specific mitochondrial targeting signals. Mitochondrial targeting signals are very diverse, however, about 70% of mitochondrial proteins carry cleavable, N-terminal extensions called presequences. These amphipathic helices with one positively charged and one hydrophobic surface target proteins to the mitochondrial matrix with the help of the TOM and TIM23 complexes in the outer and inner membranes, respectively. Translocation of proteins across the two mitochondrial membranes does not take place independently of each other. Rather, in the intermembrane space, where the two complexes meet, components of the TOM and TIM23 complexes form an intricate network of protein-protein interactions that mediates initially transfer of presequences and then of the entire precursor proteins from the outer to the inner mitochondrial membrane. In this Mini Review, we summarize our current understanding of how the TOM and TIM23 complexes cooperate with each other and highlight some of the future challenges and unresolved questions in the field.
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Affiliation(s)
| | - Dejana Mokranjac
- Biozentrum — Department of Cell Biology, LMU Munich, Munich, Germany
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21
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Malina C, Di Bartolomeo F, Kerkhoven EJ, Nielsen J. Constraint-based modeling of yeast mitochondria reveals the dynamics of protein import and iron-sulfur cluster biogenesis. iScience 2021; 24:103294. [PMID: 34755100 PMCID: PMC8564123 DOI: 10.1016/j.isci.2021.103294] [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: 03/23/2021] [Revised: 08/27/2021] [Accepted: 10/14/2021] [Indexed: 12/03/2022] Open
Abstract
Mitochondria are a hallmark of eukaryal cells and play an important role in cellular metabolism. There is a vast amount of knowledge available on mitochondrial metabolism and essential mitochondrial functions, such as protein import and iron-sulfur cluster biosynthesis, including multiple studies on the mitochondrial proteome. Therefore, there is a need for in silico approaches to facilitate the analysis of these data. Here, we present a detailed model of mitochondrial metabolism Saccharomyces cerevisiae, including protein import, iron-sulfur cluster biosynthesis, and a description of the coupling between charge translocation processes and ATP synthesis. Model analysis implied a dual dependence of absolute levels of proteins in protein import, iron-sulfur cluster biogenesis and cluster abundance on growth rate and respiratory activity. The model is instrumental in studying dynamics and perturbations in these processes and given the high conservation of mitochondrial metabolism in humans, it can provide insight into their role in human disease. Reconstruction of mitochondrial protein import and cofactor metabolism in yeast Quantification of the energy cost of metabolite transport Protein import activity depends on growth rate and respiratory activity Quantification iron-sulfur cluster requirements show growth rate dependence
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Affiliation(s)
- Carl Malina
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden.,Wallenberg Center for Protein Research, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | | | - Eduard J Kerkhoven
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden.,Wallenberg Center for Protein Research, Chalmers University of Technology, 41296 Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 412 96 Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.,BioInnovation Institute, Ole Måløes Vej 3, 2200 Copenhagen N, Denmark
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22
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Rampelt H, Pfanner N. Morpholinos meet mitochondria: Targeting organellar gene expression. Cell 2021; 184:5693-5695. [PMID: 34767774 DOI: 10.1016/j.cell.2021.10.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 12/01/2022]
Abstract
The mitochondrial genome encodes proteins central to mitochondrial function; however, transcript-specific mechanistic studies of mitochondrial gene products have been difficult because of challenges in their experimental manipulation. Cruz-Zaragoza et al. provide a solution to this challenge, introducing an elegant system for efficient translational silencing of transcripts in human mitochondria.
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Affiliation(s)
- 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.
| | - 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.
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23
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Zhao F, Zou MH. Role of the Mitochondrial Protein Import Machinery and Protein Processing in Heart Disease. Front Cardiovasc Med 2021; 8:749756. [PMID: 34651031 PMCID: PMC8505727 DOI: 10.3389/fcvm.2021.749756] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/26/2021] [Indexed: 12/12/2022] Open
Abstract
Mitochondria are essential organelles for cellular energy production, metabolic homeostasis, calcium homeostasis, cell proliferation, and apoptosis. About 99% of mammalian mitochondrial proteins are encoded by the nuclear genome, synthesized as precursors in the cytosol, and imported into mitochondria by mitochondrial protein import machinery. Mitochondrial protein import systems function not only as independent units for protein translocation, but also are deeply integrated into a functional network of mitochondrial bioenergetics, protein quality control, mitochondrial dynamics and morphology, and interaction with other organelles. Mitochondrial protein import deficiency is linked to various diseases, including cardiovascular disease. In this review, we describe an emerging class of protein or genetic variations of components of the mitochondrial import machinery involved in heart disease. The major protein import pathways, including the presequence pathway (TIM23 pathway), the carrier pathway (TIM22 pathway), and the mitochondrial intermembrane space import and assembly machinery, related translocases, proteinases, and chaperones, are discussed here. This review highlights the importance of mitochondrial import machinery in heart disease, which deserves considerable attention, and further studies are urgently needed. Ultimately, this knowledge may be critical for the development of therapeutic strategies in heart disease.
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Affiliation(s)
- Fujie Zhao
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, United States
| | - Ming-Hui Zou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, United States
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24
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Mapping protein interactions in the active TOM-TIM23 supercomplex. Nat Commun 2021; 12:5715. [PMID: 34588454 PMCID: PMC8481542 DOI: 10.1038/s41467-021-26016-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 08/19/2021] [Indexed: 11/10/2022] Open
Abstract
Nuclear-encoded mitochondrial proteins destined for the matrix have to be transported across two membranes. The TOM and TIM23 complexes facilitate the transport of precursor proteins with N-terminal targeting signals into the matrix. During transport, precursors are recognized by the TIM23 complex in the inner membrane for handover from the TOM complex. However, we have little knowledge on the organization of the TOM-TIM23 transition zone and on how precursor transfer between the translocases occurs. Here, we have designed a precursor protein that is stalled during matrix transport in a TOM-TIM23-spanning manner and enables purification of the translocation intermediate. Combining chemical cross-linking with mass spectrometric analyses and structural modeling allows us to map the molecular environment of the intermembrane space interface of TOM and TIM23 as well as the import motor interactions with amino acid resolution. Our analyses provide a framework for understanding presequence handover and translocation during matrix protein transport. The TOM and TIM23 complexes facilitate the transport of nuclear-encoded proteins into the mitochondrial matrix. Here, the authors use a stalled client protein to purify the translocation supercomplex and gain insight into the TOM-TIM23 interface and the mechanism of protein handover from the TOM to the TIM23 complex.
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25
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Walter C, Marada A, Suhm T, Ernsberger R, Muders V, Kücükköse C, Sánchez-Martín P, Hu Z, Aich A, Loroch S, Solari FA, Poveda-Huertes D, Schwierzok A, Pommerening H, Matic S, Brix J, Sickmann A, Kraft C, Dengjel J, Dennerlein S, Brummer T, Vögtle FN, Meisinger C. Global kinome profiling reveals DYRK1A as critical activator of the human mitochondrial import machinery. Nat Commun 2021; 12:4284. [PMID: 34257281 PMCID: PMC8277783 DOI: 10.1038/s41467-021-24426-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 06/15/2021] [Indexed: 11/21/2022] Open
Abstract
The translocase of the outer mitochondrial membrane TOM constitutes the organellar entry gate for nearly all precursor proteins synthesized on cytosolic ribosomes. Thus, TOM presents the ideal target to adjust the mitochondrial proteome upon changing cellular demands. Here, we identify that the import receptor TOM70 is targeted by the kinase DYRK1A and that this modification plays a critical role in the activation of the carrier import pathway. Phosphorylation of TOM70Ser91 by DYRK1A stimulates interaction of TOM70 with the core TOM translocase. This enables transfer of receptor-bound precursors to the translocation pore and initiates their import. Consequently, loss of TOM70Ser91 phosphorylation results in a strong decrease in import capacity of metabolite carriers. Inhibition of DYRK1A impairs mitochondrial structure and function and elicits a protective transcriptional response to maintain a functional import machinery. The DYRK1A-TOM70 axis will enable insights into disease mechanisms caused by dysfunctional DYRK1A, including autism spectrum disorder, microcephaly and Down syndrome.
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Affiliation(s)
- Corvin Walter
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Adinarayana Marada
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tamara Suhm
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ralf Ernsberger
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Vera Muders
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Cansu Kücükköse
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Pablo Sánchez-Martín
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Zehan Hu
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Abhishek Aich
- Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany
| | - Stefan Loroch
- Leibniz Institut für Analytische Wissenschaften - ISAS - e.V., Dortmund, Germany
| | | | - Daniel Poveda-Huertes
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Alexandra Schwierzok
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Henrike Pommerening
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Stanka Matic
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jan Brix
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Albert Sickmann
- Leibniz Institut für Analytische Wissenschaften - ISAS - e.V., Dortmund, Germany
| | - Claudine Kraft
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Jörn Dengjel
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Sven Dennerlein
- Department of Cellular Biochemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Tilman Brummer
- Institute of Molecular Medicine, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- German Cancer Consortium DKTK Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - F-Nora Vögtle
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
- Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany.
| | - Chris Meisinger
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
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26
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Increased mitochondrial protein import and cardiolipin remodelling upon early mtUPR. PLoS Genet 2021; 17:e1009664. [PMID: 34214073 PMCID: PMC8282050 DOI: 10.1371/journal.pgen.1009664] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 07/15/2021] [Accepted: 06/11/2021] [Indexed: 12/11/2022] Open
Abstract
Mitochondrial defects can cause a variety of human diseases and protective mechanisms exist to maintain mitochondrial functionality. Imbalances in mitochondrial proteostasis trigger a transcriptional program, termed mitochondrial unfolded protein response (mtUPR). However, the temporal sequence of events in mtUPR is unclear and the consequences on mitochondrial protein import are controversial. Here, we have quantitatively analyzed all main import pathways into mitochondria after different time spans of mtUPR induction. Kinetic analyses reveal that protein import into all mitochondrial subcompartments strongly increases early upon mtUPR and that this is accompanied by rapid remodelling of the mitochondrial signature lipid cardiolipin. Genetic inactivation of cardiolipin synthesis precluded stimulation of protein import and compromised cellular fitness. At late stages of mtUPR upon sustained stress, mitochondrial protein import efficiency declined. Our work clarifies the enigma of protein import upon mtUPR and identifies sequential mtUPR stages, in which an early increase in protein biogenesis to restore mitochondrial proteostasis is followed by late stages characterized by a decrease in import capacity upon prolonged stress induction. Mitochondria are essential organelles and involved in numerous important functions like ATP production, biosynthesis of metabolites and co-factors or regulation of programmed cell death. To fulfill this plethora of different tasks, mitochondria require an extensive proteome, which is build by import of nuclear-encoded precursor proteins from the cytosol. Mitochondrial defects can cause a variety of severe human disorders that often affect tissues with high energy demand e.g. heart, muscle or brain. However, protective mechanisms exist that are triggered upon mitochondrial dysfunction: Imbalances in mitochondrial proteostasis are sensed by the cell and elicit a nuclear transcriptional response, termed mitochondrial unfolded protein response (mtUPR). Transcription of mitochondrial chaperones and proteases is increased to counteract mitochondrial dysfunctions. In this study, we investigated if mtUPR progresses in different temporal stages and how protein import is affected upon mtUPR. We discover that mtUPR is subdivided into an early phase, in which protein import increases and a late phase, in which it declines. Stimulation of protein import is accompanied by an increase and remodelling of the mitochondrial signature lipid cardiolipin. Our work establishes a novel model how cells respond to dysfunctional mitochondria, in which cardiolipin and protein import are modulated as first protective measures.
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27
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Wang F, Zhang D, Zhang D, Li P, Gao Y. Mitochondrial Protein Translation: Emerging Roles and Clinical Significance in Disease. Front Cell Dev Biol 2021; 9:675465. [PMID: 34277617 PMCID: PMC8280776 DOI: 10.3389/fcell.2021.675465] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 06/09/2021] [Indexed: 12/28/2022] Open
Abstract
Mitochondria are one of the most important organelles in cells. Mitochondria are semi-autonomous organelles with their own genetic system, and can independently replicate, transcribe, and translate mitochondrial DNA. Translation initiation, elongation, termination, and recycling of the ribosome are four stages in the process of mitochondrial protein translation. In this process, mitochondrial protein translation factors and translation activators, mitochondrial RNA, and other regulatory factors regulate mitochondrial protein translation. Mitochondrial protein translation abnormalities are associated with a variety of diseases, including cancer, cardiovascular diseases, and nervous system diseases. Mutation or deletion of various mitochondrial protein translation factors and translation activators leads to abnormal mitochondrial protein translation. Mitochondrial tRNAs and mitochondrial ribosomal proteins are essential players during translation and mutations in genes encoding them represent a large fraction of mitochondrial diseases. Moreover, there is crosstalk between mitochondrial protein translation and cytoplasmic translation, and the imbalance between mitochondrial protein translation and cytoplasmic translation can affect some physiological and pathological processes. This review summarizes the regulation of mitochondrial protein translation factors, mitochondrial ribosomal proteins, mitochondrial tRNAs, and mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs) in the mitochondrial protein translation process and its relationship with diseases. The regulation of mitochondrial protein translation and cytoplasmic translation in multiple diseases is also summarized.
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Affiliation(s)
- Fei Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Deyu Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Dejiu Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China
| | - Yanyan Gao
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, China.,Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, China
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28
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Wenger C, Schneider A. Minimal peptide length required to span the mitochondrial protein translocases in Trypanosoma brucei. Mol Biochem Parasitol 2021; 244:111393. [PMID: 34197864 DOI: 10.1016/j.molbiopara.2021.111393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 10/21/2022]
Abstract
Mitochondrial protein import depends on heterooligomeric translocases in the outer and inner membranes. Using import substrates consisting of various lengths of the N-terminal part of mitochondrial dihydrolipoamide dehydrogenase (LDH) fused to dihydrofolate reductase we present an in vivo analysis showing that in Trypanosoma brucei at least 96 aa of mature LDH are required to efficiently produce an import intermediate that spans both translocases. This is different to yeast, where around 50 aa are sufficient to achieve the same task and likely reflects the different arrangement and architecture of the trypanosomal mitochondrial translocases. Furthermore, we show that formation of the stuck import intermediate leads to a strong growth inhibition suggesting that, depending on the length of the LDH, the import channels in the translocases are quantitatively blocked.
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Affiliation(s)
- Christoph Wenger
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestr. 3, CH-3012, Bern, Switzerland
| | - André Schneider
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestr. 3, CH-3012, Bern, Switzerland.
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29
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Transmembrane Coordination of Preprotein Recognition and Motor Coupling by the Mitochondrial Presequence Receptor Tim50. Cell Rep 2021; 30:3092-3104.e4. [PMID: 32130909 DOI: 10.1016/j.celrep.2020.02.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 12/13/2019] [Accepted: 02/07/2020] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial preproteins contain amino-terminal presequences directing them to the presequence translocase of the mitochondrial inner membrane (TIM23 complex). Depending on additional downstream import signals, TIM23 either inserts preproteins into the inner membrane or translocates them into the matrix. Matrix import requires the coupling of the presequence translocase-associated motor (PAM) to TIM23. The molecular mechanisms coordinating preprotein recognition by TIM23 in the intermembrane space (IMS) with PAM activation in the matrix are unknown. Here we show that subsequent to presequence recognition in the IMS, the Tim50 matrix domain facilitates the recruitment of the coupling factor Pam17. Next, the IMS domain of Tim50 promotes PAM recruitment to TIM23. Finally, the Tim50 transmembrane segment stimulates the matrix-directed import-driving force exerted by PAM. We propose that recognition of preprotein segments in the IMS and transfer of signal information across the inner membrane by Tim50 determine import motor activation.
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30
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Gomez-Fabra Gala M, Vögtle FN. Mitochondrial proteases in human diseases. FEBS Lett 2021; 595:1205-1222. [PMID: 33453058 DOI: 10.1002/1873-3468.14039] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/17/2020] [Accepted: 12/18/2020] [Indexed: 12/15/2022]
Abstract
Mitochondria contain more than 1000 different proteins, including several proteolytic enzymes. These mitochondrial proteases form a complex system that performs limited and terminal proteolysis to build the mitochondrial proteome, maintain, and control its functions or degrade mitochondrial proteins and peptides. During protein biogenesis, presequence proteases cleave and degrade mitochondrial targeting signals to obtain mature functional proteins. Processing by proteases also exerts a regulatory role in modulation of mitochondrial functions and quality control enzymes degrade misfolded, aged, or superfluous proteins. Depending on their different functions and substrates, defects in mitochondrial proteases can affect the majority of the mitochondrial proteome or only a single protein. Consequently, mutations in mitochondrial proteases have been linked to several human diseases. This review gives an overview of the components and functions of the mitochondrial proteolytic machinery and highlights the pathological consequences of dysfunctional mitochondrial protein processing and turnover.
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Affiliation(s)
- Maria Gomez-Fabra Gala
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Germany.,Faculty of Biology, University of Freiburg, Germany.,Spemann Graduate School of Biology and Medicine, University of Freiburg, Germany
| | - Friederike-Nora Vögtle
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Germany.,CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Germany
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31
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Mitochondrial control of cellular protein homeostasis. Biochem J 2021; 477:3033-3054. [PMID: 32845275 DOI: 10.1042/bcj20190654] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 07/20/2020] [Accepted: 08/03/2020] [Indexed: 02/08/2023]
Abstract
Mitochondria are involved in several vital functions of the eukaryotic cell. The majority of mitochondrial proteins are coded by nuclear DNA. Constant import of proteins from the cytosol is a prerequisite for the efficient functioning of the organelle. The protein import into mitochondria is mediated by diverse import pathways and is continuously under watch by quality control systems. However, it is often challenged by both internal and external factors, such as oxidative stress or energy shortage. The impaired protein import and biogenesis leads to the accumulation of mitochondrial precursor proteins in the cytosol and activates several stress response pathways. These defense mechanisms engage a network of processes involving transcription, translation, and protein clearance to restore cellular protein homeostasis. In this review, we provide a comprehensive analysis of various factors and processes contributing to mitochondrial stress caused by protein biogenesis failure and summarize the recovery mechanisms employed by the cell.
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32
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Kücükköse C, Taskin AA, Marada A, Brummer T, Dennerlein S, Vögtle FN. Functional coupling of presequence processing and degradation in human mitochondria. FEBS J 2021; 288:600-613. [PMID: 32491259 DOI: 10.1111/febs.15358] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 03/31/2020] [Accepted: 05/04/2020] [Indexed: 12/31/2022]
Abstract
The mitochondrial proteome is built and maintained mainly by import of nuclear-encoded precursor proteins. Most of these precursors use N-terminal presequences as targeting signals that are removed by mitochondrial matrix proteases. The essential mitochondrial processing protease MPP cleaves presequences after import into the organelle thereby enabling protein folding and functionality. The cleaved presequences are subsequently degraded by peptidases. While most of these processes have been discovered in yeast, characterization of the human enzymes is still scarce. As the matrix presequence peptidase PreP has been reported to play a role in Alzheimer's disease, analysis of impaired peptide turnover in human cells is of huge interest. Here, we report the characterization of HEK293T PreP knockout cells. Loss of PreP causes severe defects in oxidative phosphorylation and changes in nuclear expression of stress response marker genes. The mitochondrial defects upon lack of PreP result from the accumulation of presequence peptides that trigger feedback inhibition of MPP and accumulation of nonprocessed precursor proteins. Also, the mitochondrial intermediate peptidase MIP that cleaves eight residues from a subset of precursors after MPP processing is compromised upon loss of PreP suggesting that PreP also degrades MIP generated octapeptides. Investigation of the PrePR183Q patient mutation associated with neurological disorders revealed that the mutation destabilizes the protein making it susceptible to enhanced degradation and aggregation upon heat shock. Taken together, our data reveal a functional coupling between precursor processing by MPP and MIP and presequence degradation by PreP in human mitochondria that is crucial to maintain a functional organellar proteome.
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Affiliation(s)
- Cansu Kücükköse
- Faculty of Medicine, Institute of Biochemistry and Molecular Biology, ZBMZ, University of Freiburg, Germany
- Faculty of Biology, University of Freiburg, Germany
| | - Asli Aras Taskin
- Faculty of Medicine, Institute of Biochemistry and Molecular Biology, ZBMZ, University of Freiburg, Germany
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Germany
| | - Adinarayana Marada
- Faculty of Medicine, Institute of Biochemistry and Molecular Biology, ZBMZ, University of Freiburg, Germany
| | - Tilman Brummer
- Faculty of Medicine, Institute of Molecular Medicine and Cell Research, University of Freiburg, Germany
- Centre for Biological Signalling Studies BIOSS, University of Freiburg, Germany
- Comprehensive Cancer Centre Freiburg, University of Freiburg, Germany
- DKTK Partner Site Freiburg and DKFZ, Heidelberg, Germany
| | - Sven Dennerlein
- Department of Cellular Biochemistry, University Medical Center Göttingen, Germany
| | - Friederike-Nora Vögtle
- Faculty of Medicine, Institute of Biochemistry and Molecular Biology, ZBMZ, University of Freiburg, Germany
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, Germany
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33
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Shikha S, Huot JL, Schneider A, Niemann M. tRNA import across the mitochondrial inner membrane in T. brucei requires TIM subunits but is independent of protein import. Nucleic Acids Res 2020; 48:12269-12281. [PMID: 33231678 PMCID: PMC7708065 DOI: 10.1093/nar/gkaa1098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 10/20/2020] [Accepted: 11/03/2020] [Indexed: 01/27/2023] Open
Abstract
Mitochondrial tRNA import is widespread, but mechanistic insights of how tRNAs are translocated across mitochondrial membranes remain scarce. The parasitic protozoan T. brucei lacks mitochondrial tRNA genes. Consequently, it imports all organellar tRNAs from the cytosol. Here we investigated the connection between tRNA and protein translocation across the mitochondrial inner membrane. Trypanosomes have a single inner membrane protein translocase that consists of three heterooligomeric submodules, which all are required for import of matrix proteins. In vivo depletion of individual submodules shows that surprisingly only the integral membrane core module, including the protein import pore, but not the presequence-associated import motor are required for mitochondrial tRNA import. Thus we could uncouple import of matrix proteins from import of tRNAs even though both substrates are imported into the same mitochondrial subcompartment. This is reminiscent to the outer membrane where the main protein translocase but not on-going protein translocation is required for tRNA import. We also show that import of tRNAs across the outer and inner membranes are coupled to each other. Taken together, these data support the 'alternate import model', which states that tRNA and protein import while mechanistically independent use the same translocation pores but not at the same time.
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Affiliation(s)
- Shikha Shikha
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Jonathan L Huot
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - André Schneider
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Moritz Niemann
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
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34
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Vögtle F. Open questions on the mitochondrial unfolded protein response. FEBS J 2020; 288:2856-2869. [DOI: 10.1111/febs.15569] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/28/2020] [Accepted: 09/14/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Friederike‐Nora Vögtle
- Institute of Biochemistry and Molecular Biology ZBMZ Faculty of Medicine University of Freiburg Germany
- CIBSS ‐ Centre for Integrative Biological Signalling Studies University of Freiburg Germany
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35
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Karakaidos P, Rampias T. Mitonuclear Interactions in the Maintenance of Mitochondrial Integrity. Life (Basel) 2020; 10:life10090173. [PMID: 32878185 PMCID: PMC7555762 DOI: 10.3390/life10090173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 08/28/2020] [Indexed: 12/27/2022] Open
Abstract
In eukaryotic cells, mitochondria originated in an α-proteobacterial endosymbiont. Although these organelles harbor their own genome, the large majority of genes, originally encoded in the endosymbiont, were either lost or transferred to the nucleus. As a consequence, mitochondria have become semi-autonomous and most of their processes require the import of nuclear-encoded components to be functional. Therefore, the mitochondrial-specific translation has evolved to be coordinated by mitonuclear interactions to respond to the energetic demands of the cell, acquiring unique and mosaic features. However, mitochondrial-DNA-encoded genes are essential for the assembly of the respiratory chain complexes. Impaired mitochondrial function due to oxidative damage and mutations has been associated with numerous human pathologies, the aging process, and cancer. In this review, we highlight the unique features of mitochondrial protein synthesis and provide a comprehensive insight into the mitonuclear crosstalk and its co-evolution, as well as the vulnerabilities of the animal mitochondrial genome.
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36
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Lu X, Liu QX, Zhang J, Zhou D, Yang GX, Li MY, Qiu Y, Chen Q, Zheng H, Dai JG. PINK1 Overexpression Promotes Cell Migration and Proliferation via Regulation of Autophagy and Predicts a Poor Prognosis in Lung Cancer Cases. Cancer Manag Res 2020; 12:7703-7714. [PMID: 32904694 PMCID: PMC7457709 DOI: 10.2147/cmar.s262466] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/24/2020] [Indexed: 12/05/2022] Open
Abstract
Background Lung cancer remains the leading cause of cancer-related death worldwide. The human PINK1 gene (PTEN induced kinase 1, Park6), an important gene for Parkinson’s disease, was found to be associated with tumor development although the molecular mechanisms underlying this relationship remain largely unknown. Objective To analyze the clinical value and molecular mechanism of PINK1 in non-small cell lung cancer (NSCLC). Materials and Methods Western blot, qRT-PCR and Immunohistochemistry were employed to determine the levels of PINK1 in 87 paired NSCLC tissues, Oncomine and TCGA databases were also used for the evaluation of expression and prognosis of PINK1. The mitophagy, proliferation, migration, invasion, and apoptosis abilities of A549 and H1975 cells were detected, and the autophagy-related proteins in the cells were also determined. Results Immunohistochemical staining revealed higher PINK1 expression in tumor tissues, which was strongly linked to the tumor-node-metastasis classification. Survival analysis of 1085 NSCLC patients also revealed that low PINK1 expression levels were associated with significantly longer overall survival. Univariate and multivariate analyses indicated that PINK1 expression was an independent predictor of overall survival among patients with NSCLC. We also evaluated the influence of PINK1 deficiency in NSCLC cell lines (A549 and H1975), which revealed significant suppression of migration capability and cell viability, as well as a significantly elevated apoptosis ratio. In cells with stable interference of PINK1 expression, dysfunctional mitochondria accumulated while autophagy was inhibited, which indicated that cell activity suppression was mediated by the accumulation of dysfunctional mitochondria. The suppression of migration and autophagy was reversed in cells that overexpressed PINK1. Conclusion Our results suggest that PINK1 may be a potential therapeutic target and prognostic biomarker in NSCLC.
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Affiliation(s)
- Xiao Lu
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Quan-Xing Liu
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Jiao Zhang
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Dong Zhou
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Gui-Xue Yang
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Man-Yuan Li
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Yuan Qiu
- Department of General Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Qian Chen
- Cancer Center of Daping Hospital, Army Medical University, Chongqing 400042, People's Republic of China
| | - Hong Zheng
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
| | - Ji-Gang Dai
- Department of Thoracic Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China
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37
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Grevel A, Pfanner N, Becker T. Coupling of import and assembly pathways in mitochondrial protein biogenesis. Biol Chem 2020; 401:117-129. [PMID: 31513529 DOI: 10.1515/hsz-2019-0310] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 08/13/2019] [Indexed: 12/14/2022]
Abstract
Biogenesis and function of mitochondria depend on the import of about 1000 precursor proteins that are produced on cytosolic ribosomes. The translocase of the outer membrane (TOM) forms the entry gate for most proteins. After passage through the TOM channel, dedicated preprotein translocases sort the precursor proteins into the mitochondrial subcompartments. Many proteins have to be assembled into oligomeric membrane-integrated complexes in order to perform their functions. In this review, we discuss a dual role of mitochondrial preprotein translocases in protein translocation and oligomeric assembly, focusing on the biogenesis of the TOM complex and the respiratory chain. The sorting and assembly machinery (SAM) of the outer mitochondrial membrane forms a dynamic platform for coupling transport and assembly of TOM subunits. The biogenesis of the cytochrome c oxidase of the inner membrane involves a molecular circuit to adjust translation of mitochondrial-encoded core subunits to the availability of nuclear-encoded partner proteins. Thus, mitochondrial protein translocases not only import precursor proteins but can also support their assembly into functional complexes.
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Affiliation(s)
- Alexander Grevel
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, D-79104 Freiburg, Germany.,Faculty of Biology, University of Freiburg, D-79104 Freiburg, Germany
| | - Nikolaus Pfanner
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, D-79104 Freiburg, Germany.,CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, D-79104 Freiburg, Germany.,CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, D-79104 Freiburg, Germany
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38
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Larburu N, Adams CJ, Chen CS, Nowak PR, Ali MMU. Mechanism of Hsp70 specialized interactions in protein translocation and the unfolded protein response. Open Biol 2020; 10:200089. [PMID: 32810420 PMCID: PMC7479934 DOI: 10.1098/rsob.200089] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 07/07/2020] [Indexed: 01/17/2023] Open
Abstract
Hsp70 chaperones interact with substrate proteins in a coordinated fashion that is regulated by nucleotides and enhanced by assisting cochaperones. There are numerous homologues and isoforms of Hsp70 that participate in a wide variety of cellular functions. This diversity can facilitate adaption or specialization based on particular biological activity and location within the cell. In this review, we highlight two specialized binding partner proteins, Tim44 and IRE1, that interact with Hsp70 at the membrane in order to serve their respective roles in protein translocation and unfolded protein response signalling. Recent mechanistic data suggest analogy in the way the two Hsp70 homologues (BiP and mtHsp70) can bind and release from IRE1 and Tim44 upon substrate engagement. These shared mechanistic features may underlie how Hsp70 interacts with specialized binding partners and may extend our understanding of the mechanistic repertoire that Hsp70 chaperones possess.
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Affiliation(s)
| | | | | | | | - Maruf M. U. Ali
- Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London SW7 2AZ, UK
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39
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Schneider A. Evolution of mitochondrial protein import – lessons from trypanosomes. Biol Chem 2020; 401:663-676. [DOI: 10.1515/hsz-2019-0444] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 03/02/2020] [Indexed: 01/02/2023]
Abstract
AbstractThe evolution of mitochondrial protein import and the systems that mediate it marks the boundary between the endosymbiotic ancestor of mitochondria and a true organelle that is under the control of the nucleus. Protein import has been studied in great detail inSaccharomyces cerevisiae. More recently, it has also been extensively investigated in the parasitic protozoanTrypanosoma brucei, making it arguably the second best studied system. A comparative analysis of the protein import complexes of yeast and trypanosomes is provided. Together with data from other systems, this allows to reconstruct the ancestral features of import complexes that were present in the last eukaryotic common ancestor (LECA) and to identify which subunits were added later in evolution. How these data can be translated into plausible scenarios is discussed, providing insights into the evolution of (i) outer membrane protein import receptors, (ii) proteins involved in biogenesis of α-helically anchored outer membrane proteins, and (iii) of the intermembrane space import and assembly system. Finally, it is shown that the unusual presequence-associated import motor of trypanosomes suggests a scenario of how the two ancestral inner membrane protein translocases present in LECA evolved into the single bifunctional one found in extant trypanosomes.
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Affiliation(s)
- André Schneider
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
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40
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How to get to the other side of the mitochondrial inner membrane – the protein import motor. Biol Chem 2020; 401:723-736. [DOI: 10.1515/hsz-2020-0106] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/25/2020] [Indexed: 12/13/2022]
Abstract
AbstractBiogenesis of mitochondria relies on import of more than 1000 different proteins from the cytosol. Approximately 70% of these proteins follow the presequence pathway – they are synthesized with cleavable N-terminal extensions called presequences and reach the final place of their function within the organelle with the help of the TOM and TIM23 complexes in the outer and inner membranes, respectively. The translocation of proteins along the presequence pathway is powered by the import motor of the TIM23 complex. The import motor of the TIM23 complex is localized at the matrix face of the inner membrane and is likely the most complicated Hsp70-based system identified to date. How it converts the energy of ATP hydrolysis into unidirectional translocation of proteins into mitochondria remains one of the biggest mysteries of this translocation pathway. Here, the knowns and the unknowns of the mitochondrial protein import motor are discussed.
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41
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Günsel U, Paz E, Gupta R, Mathes I, Azem A, Mokranjac D. InVivo Dissection of the Intrinsically Disordered Receptor Domain of Tim23. J Mol Biol 2020; 432:3326-3337. [PMID: 32277989 DOI: 10.1016/j.jmb.2020.03.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/05/2020] [Accepted: 03/31/2020] [Indexed: 01/11/2023]
Abstract
In the intermembrane space (IMS) of mitochondria, the receptor domain of Tim23 has an essential role during translocation of hundreds of different proteins from the cytosol via the TOM and TIM23 complexes in the outer and inner membranes, respectively. This intrinsically disordered domain, which can even extend into the cytosol, was shown, mostly in vitro, to interact with several subunits of the TOM and TIM23 complexes. To obtain molecular understanding of this organizational hub in the IMS, we dissected the IMS domain of Tim23 in vivo. We show that the interaction surface of Tim23 with Tim50 is larger than previously thought and reveal an unexpected interaction of Tim23 with Pam17 in the IMS, impairment of which influences their interaction in the matrix. Furthermore, mutations of two conserved negatively charged residues of Tim23, close to the inner membrane, prevented dimerization of Tim23. The same mutations increased exposure of Tim23 on the mitochondrial surface, whereas dissipation of membrane potential decreased it. Our results reveal an intricate network of Tim23 interactions in the IMS, whose influence is transduced across two mitochondrial membranes, ensuring efficient translocation of proteins into mitochondria.
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Affiliation(s)
- Umut Günsel
- BMC-Physiological Chemistry, LMU Munich, 82152 Martinsried, Germany
| | - Eyal Paz
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ruhita Gupta
- BMC-Physiological Chemistry, LMU Munich, 82152 Martinsried, Germany
| | | | - Abdussalam Azem
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Dejana Mokranjac
- BMC-Physiological Chemistry, LMU Munich, 82152 Martinsried, Germany.
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Matta SK, Kumar A, D'Silva P. Mgr2 regulates mitochondrial preprotein import by associating with channel-forming Tim23 subunit. Mol Biol Cell 2020; 31:1112-1123. [PMID: 32186971 PMCID: PMC7353164 DOI: 10.1091/mbc.e19-12-0677] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Mgr2, a newly identified subunit of the TIM23 complex, functions as a gatekeeper of presequence translocase and thereby maintains quality control of inner membrane preproteins sorting. However, precise recruitment of the Mgr2 subunit to the core channel and how it influences the assembly of the TIM23 complex during lateral sorting of preproteins are poorly understood. Present findings provide insights into a direct association of Mgr2 with the channel-forming Tim23 subunit. Furthermore, the mutational analysis uncovers the TM1 region of Mgr2 critically required for association with Tim23 and Tim21. On the other hand, the TM2 region of Mgr2 is involved in bridging respiratory complexes to the TIM23 complex via Tim21. Importantly, both TM regions of Mgr2 are essential for lateral sorting of preprotein into the inner membrane, as well as maintaining mitochondrial morphology. Together, our findings provide mechanistic insights into the role of Mgr2 in regulating the dynamicity of the TIM23 complex assembly required for preprotein import and coupling of respiratory pathways.
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Affiliation(s)
- Srujan Kumar Matta
- Department of Biochemistry, New Biological Sciences Building, Indian Institute of Science, Bangalore-560012, India
| | - Abhishek Kumar
- Department of Biochemistry, New Biological Sciences Building, Indian Institute of Science, Bangalore-560012, India
| | - Patrick D'Silva
- Department of Biochemistry, New Biological Sciences Building, Indian Institute of Science, Bangalore-560012, India
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von Känel C, Muñoz-Gómez SA, Oeljeklaus S, Wenger C, Warscheid B, Wideman JG, Harsman A, Schneider A. Homologue replacement in the import motor of the mitochondrial inner membrane of trypanosomes. eLife 2020; 9:52560. [PMID: 32105215 PMCID: PMC7064343 DOI: 10.7554/elife.52560] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 02/26/2020] [Indexed: 01/13/2023] Open
Abstract
Many mitochondrial proteins contain N-terminal presequences that direct them to the organelle. The main driving force for their translocation across the inner membrane is provided by the presequence translocase-associated motor (PAM) which contains the J-protein Pam18. Here, we show that in the PAM of Trypanosoma brucei the function of Pam18 has been replaced by the non-orthologous euglenozoan-specific J-protein TbPam27. TbPam27 is specifically required for the import of mitochondrial presequence-containing but not for carrier proteins. Similar to yeast Pam18, TbPam27 requires an intact J-domain to function. Surprisingly, T. brucei still contains a bona fide Pam18 orthologue that, while essential for normal growth, is not involved in protein import. Thus, during evolution of kinetoplastids, Pam18 has been replaced by TbPam27. We propose that this replacement is linked to the transition from two ancestral and functionally distinct TIM complexes, found in most eukaryotes, to the single bifunctional TIM complex present in trypanosomes.
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Affiliation(s)
- Corinne von Känel
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Sergio A Muñoz-Gómez
- Center for Mechanisms of Evolution, Biodesign Institute, School of Life Sciences, Arizona State University, Tempe, United States
| | - Silke Oeljeklaus
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology and Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Christoph Wenger
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Bettina Warscheid
- Biochemistry and Functional Proteomics, Institute of Biology II, Faculty of Biology and Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Jeremy G Wideman
- Center for Mechanisms of Evolution, Biodesign Institute, School of Life Sciences, Arizona State University, Tempe, United States
| | - Anke Harsman
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Andre Schneider
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
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44
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Poveda-Huertes D, Matic S, Marada A, Habernig L, Licheva M, Myketin L, Gilsbach R, Tosal-Castano S, Papinski D, Mulica P, Kretz O, Kücükköse C, Taskin AA, Hein L, Kraft C, Büttner S, Meisinger C, Vögtle FN. An Early mtUPR: Redistribution of the Nuclear Transcription Factor Rox1 to Mitochondria Protects against Intramitochondrial Proteotoxic Aggregates. Mol Cell 2020; 77:180-188.e9. [PMID: 31630969 PMCID: PMC6941230 DOI: 10.1016/j.molcel.2019.09.026] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/20/2019] [Accepted: 09/23/2019] [Indexed: 11/29/2022]
Abstract
The mitochondrial proteome is built mainly by import of nuclear-encoded precursors, which are targeted mostly by cleavable presequences. Presequence processing upon import is essential for proteostasis and survival, but the consequences of dysfunctional protein maturation are unknown. We find that impaired presequence processing causes accumulation of precursors inside mitochondria that form aggregates, which escape degradation and unexpectedly do not cause cell death. Instead, cells survive via activation of a mitochondrial unfolded protein response (mtUPR)-like pathway that is triggered very early after precursor accumulation. In contrast to classical stress pathways, this immediate response maintains mitochondrial protein import, membrane potential, and translation through translocation of the nuclear HMG-box transcription factor Rox1 to mitochondria. Rox1 binds mtDNA and performs a TFAM-like function pivotal for transcription and translation. Induction of early mtUPR provides a reversible stress model to mechanistically dissect the initial steps in mtUPR pathways with the stressTFAM Rox1 as the first line of defense.
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Affiliation(s)
- Daniel Poveda-Huertes
- 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
| | - Stanka Matic
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Adinarayana Marada
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Lukas Habernig
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 10691 Stockholm, Sweden
| | - Mariya Licheva
- 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
| | - Lisa Myketin
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Ralf Gilsbach
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Sergi Tosal-Castano
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 10691 Stockholm, Sweden
| | - Daniel Papinski
- Max F. Perutz Laboratories, Vienna Biocenter, University of Vienna, 1030 Vienna, Austria
| | - Patrycja Mulica
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Oliver Kretz
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany; Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Cansu Kücükköse
- 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
| | - Asli Aras Taskin
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Lutz Hein
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Claudine Kraft
- 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
| | - Sabrina Büttner
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 10691 Stockholm, Sweden; Institute for Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Chris Meisinger
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany; CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
| | - F-Nora Vögtle
- 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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45
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Pariary R, Bhattacharyya D, Bhunia A. Mitochondrial-membrane association of α-synuclein: Pros and cons in consequence of Parkinson's disease pathophysiology. GENE REPORTS 2019. [DOI: 10.1016/j.genrep.2019.100423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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46
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Yamadera M, Fujimura H, Shimizu Y, Matsui M, Nakamichi I, Yokoe M, Sakoda S. Increased number of mitochondria in capillaries distributed in stroke‐like lesions of two patients with MELAS. Neuropathology 2019; 39:404-410. [DOI: 10.1111/neup.12593] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Revised: 06/14/2019] [Accepted: 07/14/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Misaki Yamadera
- Department of PathologyOsaka Police Hospital Osaka Japan
- Department of NeurologyNational Hospital Organization Toneyama National Hospital Toyonaka Japan
| | - Harutoshi Fujimura
- Department of NeurologyNational Hospital Organization Toneyama National Hospital Toyonaka Japan
| | - Yuri Shimizu
- Department of Diabetes, Metabolism and EndocrinologyMinoh City Hospital Minoh Japan
| | - Misa Matsui
- Department of NeurologyNational Hospital Organization Toneyama National Hospital Toyonaka Japan
| | | | - Masaru Yokoe
- Department of NeurologyMinoh City Hospital Minoh Japan
| | - Saburo Sakoda
- Department of NeurologyNational Hospital Organization Toneyama National Hospital Toyonaka Japan
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47
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Callegari S, Müller T, Schulz C, Lenz C, Jans DC, Wissel M, Opazo F, Rizzoli SO, Jakobs S, Urlaub H, Rehling P, Deckers M. A MICOS-TIM22 Association Promotes Carrier Import into Human Mitochondria. J Mol Biol 2019; 431:2835-2851. [PMID: 31103774 DOI: 10.1016/j.jmb.2019.05.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/10/2019] [Accepted: 05/10/2019] [Indexed: 01/05/2023]
Abstract
Mitochondrial membrane proteins with internal targeting signals are inserted into the inner membrane by the carrier translocase (TIM22 complex). For this, precursors have to be initially directed from the TOM complex in the outer mitochondrial membrane across the intermembrane space toward the TIM22 complex. How these two translocation processes are topologically coordinated is still unresolved. Using proteomic approaches, we find that the human TIM22 complex associates with the mitochondrial contact site and cristae organizing system (MICOS) complex. This association does not appear to be conserved in yeast, whereby the yeast MICOS complex instead interacts with the presequence translocase. Using a yeast mic10Δ strain and a HEK293T MIC10 knockout cell line, we characterize the role of MICOS for protein import into the mitochondrial inner membrane and matrix. We find that a physiological cristae organization promotes efficient import via the presequence pathway in yeast, while in human mitochondria, the MICOS complex is dispensable for protein import along the presequence pathway. However, in human mitochondria, the MICOS complex is required for the efficient import of carrier proteins into the mitochondrial inner membrane. Our analyses suggest that in human mitochondria, positioning of the carrier translocase at the crista junction, and potentially in vicinity to the TOM complex, is required for efficient transport into the inner membrane.
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Affiliation(s)
- Sylvie Callegari
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Tobias Müller
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Christian Schulz
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Christof Lenz
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; Department of Clinical Chemistry, Bioanalytics, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Daniel C Jans
- Department of NanoBiophotonics, Mitochondrial Structure and Dynamics Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg, 11 37077 Göttingen, Germany; Clinic for Neurology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Mirjam Wissel
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Felipe Opazo
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, von-Siebold-Strasse 3a, 37075 Göttingen, Germany; Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Silvio O Rizzoli
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, von-Siebold-Strasse 3a, 37075 Göttingen, Germany; Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Stefan Jakobs
- Department of NanoBiophotonics, Mitochondrial Structure and Dynamics Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg, 11 37077 Göttingen, Germany; Clinic for Neurology, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; Department of Clinical Chemistry, Bioanalytics, University Medical Center Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Peter Rehling
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany; Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
| | - Markus Deckers
- Department of Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
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48
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Mohanraj K, Wasilewski M, Benincá C, Cysewski D, Poznanski J, Sakowska P, Bugajska Z, Deckers M, Dennerlein S, Fernandez‐Vizarra E, Rehling P, Dadlez M, Zeviani M, Chacinska A. Inhibition of proteasome rescues a pathogenic variant of respiratory chain assembly factor COA7. EMBO Mol Med 2019; 11:emmm.201809561. [PMID: 30885959 PMCID: PMC6505684 DOI: 10.15252/emmm.201809561] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Nuclear and mitochondrial genome mutations lead to various mitochondrial diseases, many of which affect the mitochondrial respiratory chain. The proteome of the intermembrane space (IMS) of mitochondria consists of several important assembly factors that participate in the biogenesis of mitochondrial respiratory chain complexes. The present study comprehensively analyzed a recently identified IMS protein cytochrome c oxidase assembly factor 7 (COA7), or RESpiratory chain Assembly 1 (RESA1) factor that is associated with a rare form of mitochondrial leukoencephalopathy and complex IV deficiency. We found that COA7 requires the mitochondrial IMS import and assembly (MIA) pathway for efficient accumulation in the IMS We also found that pathogenic mutant versions of COA7 are imported slower than the wild-type protein, and mislocalized proteins are degraded in the cytosol by the proteasome. Interestingly, proteasome inhibition rescued both the mitochondrial localization of COA7 and complex IV activity in patient-derived fibroblasts. We propose proteasome inhibition as a novel therapeutic approach for a broad range of mitochondrial pathologies associated with the decreased levels of mitochondrial proteins.
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Affiliation(s)
- Karthik Mohanraj
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland,ReMedy International Research Agenda UnitCentre of New TechnologiesUniversity of WarsawWarsawPoland,Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| | - Michal Wasilewski
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland,Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| | | | - Dominik Cysewski
- Mass Spectrometry LabDepartment of BiophysicsInstitute of Biochemistry and BiophysicsWarsawPoland
| | - Jaroslaw Poznanski
- Department of BiophysicsInstitute of Biochemistry and BiophysicsWarsawPoland
| | - Paulina Sakowska
- Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
| | - Zaneta Bugajska
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland
| | - Markus Deckers
- Department of Cellular BiochemistryUniversity of GöttingenGöttingenGermany
| | - Sven Dennerlein
- Department of Cellular BiochemistryUniversity of GöttingenGöttingenGermany
| | | | - Peter Rehling
- Department of Cellular BiochemistryUniversity of GöttingenGöttingenGermany,Max Planck Institute for Biophysical ChemistryGöttingenGermany
| | - Michal Dadlez
- Mass Spectrometry LabDepartment of BiophysicsInstitute of Biochemistry and BiophysicsWarsawPoland
| | - Massimo Zeviani
- MRC Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Agnieszka Chacinska
- Laboratory of Mitochondrial BiogenesisCentre of New TechnologiesUniversity of WarsawWarsawPoland,ReMedy International Research Agenda UnitCentre of New TechnologiesUniversity of WarsawWarsawPoland,Laboratory of Mitochondrial BiogenesisInternational Institute of Molecular and Cell BiologyWarsawPoland
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49
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Topf U, Uszczynska-Ratajczak B, Chacinska A. Mitochondrial stress-dependent regulation of cellular protein synthesis. J Cell Sci 2019; 132:132/8/jcs226258. [DOI: 10.1242/jcs.226258] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
ABSTRACT
The production of newly synthesized proteins is vital for all cellular functions and is a determinant of cell growth and proliferation. The synthesis of polypeptide chains from mRNA molecules requires sophisticated machineries and mechanisms that need to be tightly regulated, and adjustable to current needs of the cell. Failures in the regulation of translation contribute to the loss of protein homeostasis, which can have deleterious effects on cellular function and organismal health. Unsurprisingly, the regulation of translation appears to be a crucial element in stress response mechanisms. This review provides an overview of mechanisms that modulate cytosolic protein synthesis upon cellular stress, with a focus on the attenuation of translation in response to mitochondrial stress. We then highlight links between mitochondrion-derived reactive oxygen species and the attenuation of reversible cytosolic translation through the oxidation of ribosomal proteins at their cysteine residues. We also discuss emerging concepts of how cellular mechanisms to stress are adapted, including the existence of alternative ribosomes and stress granules, and the regulation of co-translational import upon organelle stress.
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Affiliation(s)
- Ulrike Topf
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, Warsaw 02-106, Poland
| | | | - Agnieszka Chacinska
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland
- ReMedy International Research Agenda Unit, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland
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50
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A mutagenesis analysis of Tim50, the major receptor of the TIM23 complex, identifies regions that affect its interaction with Tim23. Sci Rep 2019; 9:2012. [PMID: 30765764 PMCID: PMC6375917 DOI: 10.1038/s41598-018-38353-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 12/27/2018] [Indexed: 12/03/2022] Open
Abstract
Maintenance of the mitochondrial proteome depends on import of newly made proteins from the cytosol. More than half of mitochondrial proteins are made as precursor proteins with N-terminal extensions called presequences and use the TIM23 complex for translocation into the matrix, the inner mitochondrial membrane and the intermembrane space (IMS). Tim50 is the central receptor of the complex that recognizes precursor proteins in the IMS. Additionally, Tim50 interacts with the IMS domain of the channel forming subunit, Tim23, an interaction that is essential for protein import across the mitochondrial inner membrane. In order to gain deeper insight into the molecular function of Tim50, we used random mutagenesis to determine residues that are important for its function. The temperature-sensitive mutants isolated were defective in import of TIM23-dependent precursor proteins. The residues mutated map to two distinct patches on the surface of Tim50. Notably, mutations in both patches impaired the interaction of Tim50 with Tim23. We propose that two regions of Tim50 play a role in its interaction with Tim23 and thereby affect the import function of the complex.
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