1
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Wilson ZN, Balasubramaniam SS, Wong S, Schuler MH, Wopat MJ, Hughes AL. Mitochondrial-derived compartments remove surplus proteins from the outer mitochondrial membrane. J Cell Biol 2024; 223:e202307036. [PMID: 39136938 PMCID: PMC11320589 DOI: 10.1083/jcb.202307036] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 05/24/2024] [Accepted: 07/18/2024] [Indexed: 09/13/2024] Open
Abstract
The outer mitochondrial membrane (OMM) creates a boundary that imports most of the mitochondrial proteome while removing extraneous or damaged proteins. How the OMM senses aberrant proteins and remodels to maintain OMM integrity remains unresolved. Previously, we identified a mitochondrial remodeling mechanism called the mitochondrial-derived compartment (MDC) that removes a subset of the mitochondrial proteome. Here, we show that MDCs specifically sequester proteins localized only at the OMM, providing an explanation for how select mitochondrial proteins are incorporated into MDCs. Remarkably, selective sorting into MDCs also occurs within the OMM, as subunits of the translocase of the outer membrane (TOM) complex are excluded from MDCs unless assembly of the TOM complex is impaired. Considering that overloading the OMM with mitochondrial membrane proteins or mistargeted tail-anchored membrane proteins induces MDCs to form and sequester these proteins, we propose that one functional role of MDCs is to create an OMM-enriched trap that segregates and sequesters excess proteins from the mitochondrial surface.
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Affiliation(s)
- Zachary N Wilson
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA
| | | | - Sara Wong
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Max-Hinderk Schuler
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Mitchell J Wopat
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Adam L Hughes
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, USA
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2
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Medikonda J, Wankar N, Asalla S, Raja SO, Yandrapally S, Jindal H, Agarwal A, Pant C, Kalivendi SV, Kumar Dubey H, Mohareer K, Gulyani A, Banerjee S. Rv0547c, a functional oxidoreductase, supports Mycobacterium tuberculosis persistence by reprogramming host mitochondrial fatty acid metabolism. Mitochondrion 2024; 78:101931. [PMID: 38986924 DOI: 10.1016/j.mito.2024.101931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 07/01/2024] [Accepted: 07/07/2024] [Indexed: 07/12/2024]
Abstract
Mycobacterium tuberculosis (Mtb) successfully thrives in the host by adjusting its metabolism and manipulating the host environment. In this study, we investigated the role of Rv0547c, a protein that carries mitochondria-targeting sequence (MTS), in mycobacterial persistence. We show that Rv0547c is a functional oxidoreductase that targets host-cell mitochondria. Interestingly, the localization of Rv0547c to mitochondria was independent of the predicted MTS but depended on specific arginine residues at the N- and C-terminals. As compared to the mitochondria-localization defective mutant, Rv0547c-2SDM, wild-type Rv0547c increased mitochondrial membrane fluidity and spare respiratory capacity. To comprehend the possible reason, comparative lipidomics was performed that revealed a reduced variability of long-chain and very long-chain fatty acids as well as altered levels of phosphatidylcholine and phosphatidylinositol class of lipids upon expression of Rv0547c, explaining the increased membrane fluidity. Additionally, the over representation of propionate metabolism and β-oxidation intermediates in Rv0547c-targeted mitochondrial fractions indicated altered fatty acid metabolism, which corroborated with changes in oxygen consumption rate (OCR) upon etomoxir treatment in HEK293T cells transiently expressing Rv0547c, resulting in enhanced mitochondrial fatty acid oxidation capacity. Furthermore, Mycobacterium smegmatis over expressing Rv0547c showed increased persistence during infection of THP-1 macrophages, which correlated with its increased expression in Mtb during oxidative and nutrient starvation stresses. This study identified for the first time an Mtb protein that alters mitochondrial metabolism and aids in survival in host macrophages by altering fatty acid metabolism to its benefit and, at the same time increases mitochondrial spare respiratory capacity to mitigate infection stresses and maintain cell viability.
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Affiliation(s)
- Jayashankar Medikonda
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Nandini Wankar
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Suman Asalla
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Sufi O Raja
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Sriram Yandrapally
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Haneesh Jindal
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Anushka Agarwal
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Chitrakshi Pant
- CSIR-Indian Institute of Chemical Technology (IICT), Uppal Road, Hyderabad, India 500007
| | - Shasi V Kalivendi
- CSIR-Indian Institute of Chemical Technology (IICT), Uppal Road, Hyderabad, India 500007
| | - Harish Kumar Dubey
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Krishnaveni Mohareer
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Akash Gulyani
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046
| | - Sharmistha Banerjee
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India 500046.
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3
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Hirata R, Mogi Y, Takahashi K, Nozaki H, Higashiyama T, Yoshida Y. Simple prerequisite of presequence for mitochondrial protein import in the unicellular red alga Cyanidioschyzon merolae. J Cell Sci 2024; 137:jcs262042. [PMID: 38940185 PMCID: PMC11298712 DOI: 10.1242/jcs.262042] [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: 02/19/2024] [Accepted: 06/13/2024] [Indexed: 06/29/2024] Open
Abstract
Mitochondrial biogenesis relies on hundreds of proteins that are derived from genes encoded in the nucleus. According to the characteristic properties of N-terminal targeting peptides (TPs) and multi-step authentication by the protein translocase called the TOM complex, nascent polypeptides satisfying the requirements are imported into mitochondria. However, it is unknown whether eukaryotic cells with a single mitochondrion per cell have a similar complexity of presequence requirements for mitochondrial protein import compared to other eukaryotes with multiple mitochondria. Based on putative mitochondrial TP sequences in the unicellular red alga Cyanidioschyzon merolae, we designed synthetic TPs and showed that functional TPs must have at least one basic residue and a specific amino acid composition, although their physicochemical properties are not strictly determined. Combined with the simple composition of the TOM complex in C. merolae, our results suggest that a regional positive charge in TPs is verified solely by TOM22 for mitochondrial protein import in C. merolae. The simple authentication mechanism indicates that the monomitochondrial C. merolae does not need to increase the cryptographic complexity of the lock-and-key mechanism for mitochondrial protein import.
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Affiliation(s)
- Riko Hirata
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yuko Mogi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Kohei Takahashi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Hisayoshi Nozaki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
- Biodiversity Division, National Institute for Environmental Studies, Ibaraki 305-8506, Japan
| | - Tetsuya Higashiyama
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yamato Yoshida
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
- Japan Science and Technology Agency (JST), PRESTO, Tokyo 113-0033, Japan
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4
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Shi R, Lin X. Illuminating the Cryptococcus neoformans species complex: unveiling intracellular structures with fluorescent-protein-based markers. Genetics 2024; 227:iyae059. [PMID: 38752295 PMCID: PMC11228865 DOI: 10.1093/genetics/iyae059] [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: 01/22/2024] [Accepted: 04/06/2024] [Indexed: 07/09/2024] Open
Abstract
Cryptococcus neoformans is a fungal pathogen of the top critical priority recognized by the World Health Organization. This clinically important fungus also serves as a eukaryotic model organism. A variety of resources have been generated to facilitate investigation of the C. neoformans species complex, including congenic pairs, well-annotated genomes, genetic editing tools, and gene deletion sets. Here, we generated a set of strains with all major organelles fluorescently marked. We tested short organelle-specific targeting sequences and successfully labeled the following organelles by fusing the targeting sequences with a fluorescence protein: the plasma membrane, the nucleus, the peroxisome, and the mitochondrion. We used native cryptococcal Golgi and late endosomal proteins fused with a fluorescent protein to label these two organelles. These fluorescence markers were verified via colocalization using organelle-specific dyes. All the constructs for the fluorescent protein tags were integrated in an intergenic safe haven region. These organelle-marked strains were examined for growth and various phenotypes. We demonstrated that these tagged strains could be employed to track cryptococcal interaction with the host in phagocytosis assays. These strains also allowed us to discover remarkable differences in the dynamics of proteins targeted to different organelles during sexual reproduction. Additionally, we revealed that "dormant" spores transcribed and synthesized their own proteins and trafficked the proteins to the appropriate subcellular compartments, demonstrating that spores are metabolically active. We anticipate that these newly generated fluorescent markers will greatly facilitate further investigation of cryptococcal biology and pathogenesis.
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Affiliation(s)
- Ran Shi
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
| | - Xiaorong Lin
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
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5
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Marada A, Walter C, Suhm T, Shankar S, Nandy A, Brummer T, Dhaouadi I, Vögtle FN, Meisinger C. DYRK1A signalling synchronizes the mitochondrial import pathways for metabolic rewiring. Nat Commun 2024; 15:5265. [PMID: 38902238 PMCID: PMC11189921 DOI: 10.1038/s41467-024-49611-4] [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: 09/19/2023] [Accepted: 06/12/2024] [Indexed: 06/22/2024] Open
Abstract
Mitochondria require an extensive proteome to maintain a variety of metabolic reactions, and changes in cellular demand depend on rapid adaptation of the mitochondrial protein composition. The TOM complex, the organellar entry gate for mitochondrial precursors in the outer membrane, is a target for cytosolic kinases to modulate protein influx. DYRK1A phosphorylation of the carrier import receptor TOM70 at Ser91 enables its efficient docking and thus transfer of precursor proteins to the TOM complex. Here, we probe TOM70 phosphorylation in molecular detail and find that TOM70 is not a CK2 target nor import receptor for MIC19 as previously suggested. Instead, we identify TOM20 as a MIC19 import receptor and show off-target inhibition of the DYRK1A-TOM70 axis with the clinically used CK2 inhibitor CX4945 which activates TOM20-dependent import pathways. Taken together, modulation of DYRK1A signalling adapts the central mitochondrial protein entry gate via synchronization of TOM70- and TOM20-dependent import pathways for metabolic rewiring. Thus, DYRK1A emerges as a cytosolic surveillance kinase to regulate and fine-tune mitochondrial protein biogenesis.
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Affiliation(s)
- Adinarayana Marada
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany
| | - Corvin Walter
- 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
| | - Tamara Suhm
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany
| | - Sahana Shankar
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany
| | - Arpita Nandy
- 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
- Spemann Graduate School of Biology and Medicine, University of Freiburg, 79104, Freiburg, Germany
| | - Tilman Brummer
- Institute of Molecular Medicine, ZBMZ, Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany
- German Cancer Consortium DKTK Partner Site Freiburg, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ines Dhaouadi
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany
| | - F-Nora Vögtle
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120, Heidelberg, Germany.
- Network Aging Research, Heidelberg University, 69120, Heidelberg, Germany.
- CIBSS - Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104, Freiburg, Germany.
| | - 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.
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6
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Crameri JJ, Palmer CS, Stait T, Jackson TD, Lynch M, Sinclair A, Frajman LE, Compton AG, Coman D, Thorburn DR, Frazier AE, Stojanovski D. Reduced Protein Import via TIM23 SORT Drives Disease Pathology in TIMM50-Associated Mitochondrial Disease. Mol Cell Biol 2024; 44:226-244. [PMID: 38828998 PMCID: PMC11204040 DOI: 10.1080/10985549.2024.2353652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 05/07/2024] [Indexed: 06/05/2024] Open
Abstract
TIMM50 is a core subunit of the TIM23 complex, the mitochondrial inner membrane translocase responsible for the import of pre-sequence-containing precursors into the mitochondrial matrix and inner membrane. Here we describe a mitochondrial disease patient who is homozygous for a novel variant in TIMM50 and establish the first proteomic map of mitochondrial disease associated with TIMM50 dysfunction. We demonstrate that TIMM50 pathogenic variants reduce the levels and activity of endogenous TIM23 complex, which significantly impacts the mitochondrial proteome, resulting in a combined oxidative phosphorylation (OXPHOS) defect and changes to mitochondrial ultrastructure. Using proteomic data sets from TIMM50 patient fibroblasts and a TIMM50 HEK293 cell model of disease, we reveal that laterally released substrates imported via the TIM23SORT complex pathway are most sensitive to loss of TIMM50. Proteins involved in OXPHOS and mitochondrial ultrastructure are enriched in the TIM23SORT substrate pool, providing a biochemical mechanism for the specific defects in TIMM50-associated mitochondrial disease patients. These results highlight the power of using proteomics to elucidate molecular mechanisms of disease and uncovering novel features of fundamental biology, with the implication that human TIMM50 may have a more pronounced role in lateral insertion than previously understood.
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Affiliation(s)
- Jordan J. Crameri
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
- The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - Catherine S. Palmer
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
- The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - Tegan Stait
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
- Victorian Clinical Genetics Services, Royal Children’s Hospital, Parkville, Victoria, Australia
| | - Thomas D. Jackson
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
- The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - Matthew Lynch
- Neurosciences Department, Queensland Children’s Hospital, South Brisbane, Queensland, Australia
- Department of Metabolic Medicine, Queensland Children’s Hospital, South Brisbane, Queensland, Australia
- School of Medicine, University of Queensland, St Lucia, Queensland, Australia
| | - Adriane Sinclair
- Neurosciences Department, Queensland Children’s Hospital, South Brisbane, Queensland, Australia
| | - Leah E. Frajman
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
| | - Alison G. Compton
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
- Victorian Clinical Genetics Services, Royal Children’s Hospital, Parkville, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia
| | - David Coman
- Department of Metabolic Medicine, Queensland Children’s Hospital, South Brisbane, Queensland, Australia
- School of Medicine, University of Queensland, St Lucia, Queensland, Australia
| | - David R. Thorburn
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
- Victorian Clinical Genetics Services, Royal Children’s Hospital, Parkville, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia
| | - Ann E. Frazier
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia
| | - Diana Stojanovski
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
- The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
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7
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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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8
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Paz E, Jain S, Gottfried I, Staretz-Chacham O, Mahajnah M, Bagchi P, Seyfried NT, Ashery U, Azem A. Biochemical and neurophysiological effects of deficiency of the mitochondrial import protein TIMM50. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.20.594480. [PMID: 38826427 PMCID: PMC11142075 DOI: 10.1101/2024.05.20.594480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
TIMM50, an essential TIM23 complex subunit, is suggested to facilitate the import of ∼60% of the mitochondrial proteome. In this study, we characterized a TIMM50 disease causing mutation in human fibroblasts, and noted significant decreases in TIM23 core protein levels (TIMM50, TIMM17A/B, and TIMM23). Strikingly, TIMM50 deficiency had no impact on the steady state levels of most of its substrates, challenging the currently accepted import dogma of the essential general import role of TIM23 and suggesting that fully functioning TIM23 complex is not essential for maintaining the steady state level of the majority of mitochondrial proteins. As TIMM50 mutations have been linked to severe neurological phenotypes, we aimed to characterize TIMM50 defects in manipulated mammalian neurons. TIMM50 knockdown in mouse neurons had a minor effect on the steady state level of most of the mitochondrial proteome, supporting the results observed in patient fibroblasts. Amongst the few affected TIM23 substrates, a decrease in the steady state level of components of the intricate oxidative phosphorylation and mitochondrial ribosome complexes was evident. This led to declined respiration rates in fibroblasts and neurons, reduced cellular ATP levels and defective mitochondrial trafficking in neuronal processes, possibly contributing to the developmental defects observed in patients with TIMM50 disease. Finally, increased electrical activity was observed in TIMM50 deficient mice neuronal cells, which correlated with reduced levels of KCNJ10 and KCNA2 plasma membrane potassium channels, likely underlying the patients' epileptic phenotype.
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9
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Yamano K, Kinefuchi H, Kojima W. Mitochondrial quality control via organelle and protein degradation. J Biochem 2024; 175:487-494. [PMID: 38102729 DOI: 10.1093/jb/mvad106] [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: 11/07/2023] [Accepted: 11/20/2023] [Indexed: 12/17/2023] Open
Abstract
Mitochondria are essential eukaryotic organelles that produce ATP as well as synthesize various macromolecules. They also participate in signalling pathways such as the innate immune response and apoptosis. These diverse functions are performed by >1,000 different mitochondrial proteins. Although mitochondria are continuously exposed to potentially damaging conditions such as reactive oxygen species, proteases/peptidases localized in different mitochondrial subcompartments, termed mitoproteases, maintain mitochondrial quality and integrity. In addition to processing incoming precursors and degrading damaged proteins, mitoproteases also regulate metabolic reactions, mitochondrial protein half-lives and gene transcription. Impaired mitoprotease function is associated with various pathologies. In this review, we highlight recent advances in our understanding of mitochondrial quality control regulated by autophagy, ubiquitin-proteasomes and mitoproteases.
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Affiliation(s)
- Koji Yamano
- Department of Biomolecular Pathogenesis, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Hiroki Kinefuchi
- Department of Biomolecular Pathogenesis, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan
| | - Waka Kojima
- Department of Biomolecular Pathogenesis, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
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10
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Moretti-Horten DN, Peselj C, Taskin AA, Myketin L, Schulte U, Einsle O, Drepper F, Luzarowski M, Vögtle FN. Synchronized assembly of the oxidative phosphorylation system controls mitochondrial respiration in yeast. Dev Cell 2024; 59:1043-1057.e8. [PMID: 38508182 DOI: 10.1016/j.devcel.2024.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 01/19/2024] [Accepted: 02/28/2024] [Indexed: 03/22/2024]
Abstract
Control of protein stoichiometry is essential for cell function. Mitochondrial oxidative phosphorylation (OXPHOS) presents a complex stoichiometric challenge as the ratio of the electron transport chain (ETC) and ATP synthase must be tightly controlled, and assembly requires coordinated integration of proteins encoded in the nuclear and mitochondrial genome. How correct OXPHOS stoichiometry is achieved is unknown. We identify the Mitochondrial Regulatory hub for respiratory Assembly (MiRA) platform, which synchronizes ETC and ATP synthase biogenesis in yeast. Molecularly, this is achieved by a stop-and-go mechanism: the uncharacterized protein Mra1 stalls complex IV assembly. Two "Go" signals are required for assembly progression: binding of the complex IV assembly factor Rcf2 and Mra1 interaction with an Atp9-translating mitoribosome induce Mra1 degradation, allowing synchronized maturation of complex IV and the ATP synthase. Failure of the stop-and-go mechanism results in cell death. MiRA controls OXPHOS assembly, ensuring correct stoichiometry of protein machineries encoded by two different genomes.
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Affiliation(s)
- Daiana N Moretti-Horten
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany; 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
| | - Carlotta Peselj
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - Asli Aras Taskin
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Lisa Myketin
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Uwe Schulte
- Institute of Physiology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Oliver Einsle
- Institut für Biochemie, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Friedel Drepper
- 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; Biochemistry & Functional Proteomics, Institute of Biology II, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Marcin Luzarowski
- Core Facility for Mass Spectrometry and Proteomics, Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany
| | - F-Nora Vögtle
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany; 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; Network Aging Research, Heidelberg University, 69120 Heidelberg, Germany.
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11
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Koch C, Lenhard S, Räschle M, Prescianotto-Baschong C, Spang A, Herrmann JM. The ER-SURF pathway uses ER-mitochondria contact sites for protein targeting to mitochondria. EMBO Rep 2024; 25:2071-2096. [PMID: 38565738 PMCID: PMC11014988 DOI: 10.1038/s44319-024-00113-w] [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: 08/31/2023] [Revised: 02/14/2024] [Accepted: 02/20/2024] [Indexed: 04/04/2024] Open
Abstract
Most mitochondrial proteins are synthesized on cytosolic ribosomes and imported into mitochondria in a post-translational reaction. Mitochondrial precursor proteins which use the ER-SURF pathway employ the surface of the endoplasmic reticulum (ER) as an important sorting platform. How they reach the mitochondrial import machinery from the ER is not known. Here we show that mitochondrial contact sites play a crucial role in the ER-to-mitochondria transfer of precursor proteins. The ER mitochondria encounter structure (ERMES) and Tom70, together with Djp1 and Lam6, are part of two parallel and partially redundant ER-to-mitochondria delivery routes. When ER-to-mitochondria transfer is prevented by loss of these two contact sites, many precursors of mitochondrial inner membrane proteins are left stranded on the ER membrane, resulting in mitochondrial dysfunction. Our observations support an active role of the ER in mitochondrial protein biogenesis.
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Affiliation(s)
- Christian Koch
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Svenja Lenhard
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Markus Räschle
- Molecular Genetics, University of Kaiserslautern, Kaiserslautern, Germany
| | | | - Anne Spang
- Biozentrum, University of Basel, 4056, Basel, Switzerland
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12
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Needs HI, Glover E, Pereira GC, Witt A, Hübner W, Dodding MP, Henley JM, Collinson I. Rescue of mitochondrial import failure by intercellular organellar transfer. Nat Commun 2024; 15:988. [PMID: 38307874 PMCID: PMC10837123 DOI: 10.1038/s41467-024-45283-2] [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: 02/01/2023] [Accepted: 01/19/2024] [Indexed: 02/04/2024] Open
Abstract
Mitochondria are the powerhouses of eukaryotic cells, composed mostly of nuclear-encoded proteins imported from the cytosol. Thus, problems with the import machinery will disrupt their regenerative capacity and the cell's energy supplies - particularly troublesome for energy-demanding cells of nervous tissue and muscle. Unsurprisingly then, import breakdown is implicated in disease. Here, we explore the consequences of import failure in mammalian cells; wherein, blocking the import machinery impacts mitochondrial ultra-structure and dynamics, but, surprisingly, does not affect import. Our data are consistent with a response involving intercellular mitochondrial transport via tunnelling nanotubes to import healthy mitochondria and jettison those with blocked import sites. These observations support the existence of a widespread mechanism for the rescue of mitochondrial dysfunction.
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Affiliation(s)
- Hope I Needs
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Emily Glover
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Gonçalo C Pereira
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
- Nanna Therapeutics, Merrifield Centre, Rosemary Lane, Cambridge, CB1 3LQ, UK
| | - Alina Witt
- Fakultät für Physik, Universität Bielefeld, Bielefeld, Postfach 100131 D-33501, Germany
| | - Wolfgang Hübner
- Fakultät für Physik, Universität Bielefeld, Bielefeld, Postfach 100131 D-33501, Germany
| | - Mark P Dodding
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Jeremy M Henley
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK.
| | - Ian Collinson
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK.
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13
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Bittner E, Stehlik T, Lam J, Dimitrov L, Heimerl T, Schöck I, Harberding J, Dornes A, Heymons N, Bange G, Schuldiner M, Zalckvar E, Bölker M, Schekman R, Freitag J. Proteins that carry dual targeting signals can act as tethers between peroxisomes and partner organelles. PLoS Biol 2024; 22:e3002508. [PMID: 38377076 PMCID: PMC10906886 DOI: 10.1371/journal.pbio.3002508] [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: 09/08/2023] [Revised: 03/01/2024] [Accepted: 01/19/2024] [Indexed: 02/22/2024] Open
Abstract
Peroxisomes are organelles with crucial functions in oxidative metabolism. To correctly target to peroxisomes, proteins require specialized targeting signals. A mystery in the field is the sorting of proteins that carry a targeting signal for peroxisomes and as well as for other organelles, such as mitochondria or the endoplasmic reticulum (ER). Exploring several of these proteins in fungal model systems, we observed that they can act as tethers bridging organelles together to create contact sites. We show that in Saccharomyces cerevisiae this mode of tethering involves the peroxisome import machinery, the ER-mitochondria encounter structure (ERMES) at mitochondria and the guided entry of tail-anchored proteins (GET) pathway at the ER. Our findings introduce a previously unexplored concept of how dual affinity proteins can regulate organelle attachment and communication.
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Affiliation(s)
- Elena Bittner
- Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Thorsten Stehlik
- Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Jason Lam
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
| | - Lazar Dimitrov
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
| | - Thomas Heimerl
- Department of Chemistry, Philipps-University Marburg, Marburg, Germany
- Center for Synthetic Microbiology, Philipps-University Marburg, Marburg, Germany
| | - Isabelle Schöck
- Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Jannik Harberding
- Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Anita Dornes
- Department of Chemistry, Philipps-University Marburg, Marburg, Germany
- Center for Synthetic Microbiology, Philipps-University Marburg, Marburg, Germany
| | - Nikola Heymons
- Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Gert Bange
- Department of Chemistry, Philipps-University Marburg, Marburg, Germany
- Center for Synthetic Microbiology, Philipps-University Marburg, Marburg, Germany
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Einat Zalckvar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Bölker
- Department of Biology, Philipps-University Marburg, Marburg, Germany
- Center for Synthetic Microbiology, Philipps-University Marburg, Marburg, Germany
| | - Randy Schekman
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
| | - Johannes Freitag
- Department of Biology, Philipps-University Marburg, Marburg, Germany
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
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14
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Marié IJ, Lahiri T, Önder Ö, Elenitoba-Johnson KS, Levy DE. Structural determinants of mitochondrial STAT3 targeting and function. MITOCHONDRIAL COMMUNICATIONS 2024; 2:1-13. [PMID: 38500969 PMCID: PMC10947224 DOI: 10.1016/j.mitoco.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Signal transducer and activator of transcription (STAT) 3 has been found within mitochondria in addition to its canonical role of shuttling between cytoplasm and nucleus during cytokine signaling. Mitochondrial STAT3 has been implicated in modulation of cellular metabolism, largely through effects on the respiratory electron transport chain. However, the structural requirements underlying mitochondrial targeting and function have remained unclear. Here, we show that mitochondrial STAT3 partitions between mitochondrial compartments defined by differential detergent solubility, suggesting that mitochondrial STAT3 is membrane associated. The majority of STAT3 was found in an SDS soluble fraction copurifying with respiratory chain proteins, including numerous components of the complex I NADH dehydrogenase, while a minor component was found with proteins of the mitochondrial translation machinery. Mitochondrial targeting of STAT3 required the amino-terminal domain, and an internal linker domain motif also directed mitochondrial translocation. However, neither the phosphorylation of serine 727 nor the presence of mitochondrial DNA was required for the mitochondrial localization of STAT3. Two cysteine residues in the STAT3 SH2 domain, which have been previously suggested to be targets for protein palmitoylation, were also not required for mitochondrial translocation, but were required for its function as an enhancer of complex I activity. These structural determinants of STAT3 mitochondrial targeting and function provide potential therapeutic targets for disrupting the activity of mitochondrial STAT3 in diseases such as cancer.
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Affiliation(s)
- Isabelle J. Marié
- Department of Pathology and Perlmutter Cancer Center, NYU Grossman School of Medicine, New York, NY, 10128, USA
| | - Tanaya Lahiri
- Department of Pathology and Perlmutter Cancer Center, NYU Grossman School of Medicine, New York, NY, 10128, USA
| | - Özlem Önder
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Kojo S.J. Elenitoba-Johnson
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - David E. Levy
- Department of Pathology and Perlmutter Cancer Center, NYU Grossman School of Medicine, New York, NY, 10128, USA
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15
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Barba-Aliaga M, Bernal V, Rong C, Zid BM, Alepuz P. eIF5A controls mitoprotein import by relieving ribosome stalling at the TIM50 translocase mRNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.19.572290. [PMID: 38187585 PMCID: PMC10769225 DOI: 10.1101/2023.12.19.572290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The efficient import of nuclear-encoded proteins into mitochondria is crucial for proper mitochondrial function. The conserved translation factor eIF5A is primarily known as an elongation factor which binds ribosomes to alleviate ribosome stalling at sequences encoding polyprolines or combinations of proline with glycine and charged amino acids. eIF5A is known to impact the mitochondrial function across a variety of species although the precise molecular mechanism underlying this impact remains unclear. We found that depletion of eIF5A in yeast drives reduced translation and levels of TCA cycle and oxidative phosphorylation proteins. We further found that loss of eIF5A leads to the accumulation of mitoprotein precursors in the cytosol as well as to the induction of a mitochondrial import stress response. Here we identify an essential polyproline-containing protein as a direct eIF5A target for translation: the mitochondrial inner membrane protein Tim50, which is the receptor subunit of the TIM23 translocase complex. We show how eIF5A directly controls mitochondrial protein import through the alleviation of ribosome stalling along TIM50 mRNA at the mitochondrial surface. Removal of the polyprolines from Tim50 rescues the mitochondrial import stress response, as well as the translation of oxidative phosphorylation reporter genes in an eIF5A loss of function. Overall, our findings elucidate how eIF5A impacts the mitochondrial function by reducing ribosome stalling and facilitating protein translation, thereby positively impacting the mitochondrial import process.
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Affiliation(s)
- Marina Barba-Aliaga
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
| | - Vanessa Bernal
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
| | - Cynthia Rong
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, United States
| | - Brian M Zid
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, United States
| | - Paula Alepuz
- Instituto de Biotecnología y Biomedicina (Biotecmed), Universitat de València, 46100 València, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universitat de València, 46100 València, Spain
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16
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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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17
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Zhou X, Yang Y, Wang G, Wang S, Sun D, Ou X, Lian Y, Li L. Molecular pathway of mitochondrial preprotein import through the TOM-TIM23 supercomplex. Nat Struct Mol Biol 2023; 30:1996-2008. [PMID: 37696957 DOI: 10.1038/s41594-023-01103-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 08/18/2023] [Indexed: 09/13/2023]
Abstract
Over half of mitochondrial proteins are imported from the cytosol via the pre-sequence pathway, controlled by the TOM complex in the outer membrane and the TIM23 complex in the inner membrane. The mechanisms through which proteins are translocated via the TOM and TIM23 complexes remain unclear. Here we report the assembly of the active TOM-TIM23 supercomplex of Saccharomyces cerevisiae with translocating polypeptide substrates. Electron cryo-microscopy analyses reveal that the polypeptide substrates pass the TOM complex through the center of a Tom40 subunit, interacting with a glutamine-rich region. Structural and biochemical analyses show that the TIM23 complex contains a heterotrimer of the subunits Tim23, Tim17 and Mgr2. The polypeptide substrates are shielded from lipids by Mgr2 and Tim17, which creates a translocation pathway characterized by a negatively charged entrance and a central hydrophobic region. These findings reveal an unexpected pre-sequence pathway through the TOM-TIM23 supercomplex spanning the double membranes of mitochondria.
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Affiliation(s)
- Xueyin Zhou
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Yuqi Yang
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Guopeng Wang
- School of Life Sciences, Peking University, Beijing, China
| | - Shanshan Wang
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Dongjie Sun
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Xiaomin Ou
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Yuke Lian
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Long Li
- State Key Laboratory of Membrane Biology, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China.
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18
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Reed AL, Mitchell W, Alexandrescu AT, Alder NN. Interactions of amyloidogenic proteins with mitochondrial protein import machinery in aging-related neurodegenerative diseases. Front Physiol 2023; 14:1263420. [PMID: 38028797 PMCID: PMC10652799 DOI: 10.3389/fphys.2023.1263420] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 10/02/2023] [Indexed: 12/01/2023] Open
Abstract
Most mitochondrial proteins are targeted to the organelle by N-terminal mitochondrial targeting sequences (MTSs, or "presequences") that are recognized by the import machinery and subsequently cleaved to yield the mature protein. MTSs do not have conserved amino acid compositions, but share common physicochemical properties, including the ability to form amphipathic α-helical structures enriched with basic and hydrophobic residues on alternating faces. The lack of strict sequence conservation implies that some polypeptides can be mistargeted to mitochondria, especially under cellular stress. The pathogenic accumulation of proteins within mitochondria is implicated in many aging-related neurodegenerative diseases, including Alzheimer's, Parkinson's, and Huntington's diseases. Mechanistically, these diseases may originate in part from mitochondrial interactions with amyloid-β precursor protein (APP) or its cleavage product amyloid-β (Aβ), α-synuclein (α-syn), and mutant forms of huntingtin (mHtt), respectively, that are mediated in part through their associations with the mitochondrial protein import machinery. Emerging evidence suggests that these amyloidogenic proteins may present cryptic targeting signals that act as MTS mimetics and can be recognized by mitochondrial import receptors and transported into different mitochondrial compartments. Accumulation of these mistargeted proteins could overwhelm the import machinery and its associated quality control mechanisms, thereby contributing to neurological disease progression. Alternatively, the uptake of amyloidogenic proteins into mitochondria may be part of a protein quality control mechanism for clearance of cytotoxic proteins. Here we review the pathomechanisms of these diseases as they relate to mitochondrial protein import and effects on mitochondrial function, what features of APP/Aβ, α-syn and mHtt make them suitable substrates for the import machinery, and how this information can be leveraged for the development of therapeutic interventions.
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Affiliation(s)
- Ashley L. Reed
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
| | - Wayne Mitchell
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Andrei T. Alexandrescu
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
| | - Nathan N. Alder
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
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19
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Sidorczuk K, Mackiewicz P, Pietluch F, Gagat P. Characterization of signal and transit peptides based on motif composition and taxon-specific patterns. Sci Rep 2023; 13:15751. [PMID: 37735485 PMCID: PMC10514287 DOI: 10.1038/s41598-023-42987-1] [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: 05/12/2023] [Accepted: 09/17/2023] [Indexed: 09/23/2023] Open
Abstract
Targeting peptides or presequences are N-terminal extensions of proteins that encode information about their cellular localization. They include signal peptides (SP), which target proteins to the endoplasmic reticulum, and transit peptides (TP) directing proteins to the organelles of endosymbiotic origin: chloroplasts and mitochondria. TPs were hypothesized to have evolved from antimicrobial peptides (AMPs), which are responsible for the host defence against microorganisms, including bacteria, fungi and viruses. In this study, we performed comprehensive bioinformatic analyses of amino acid motifs of targeting peptides and AMPs using a curated set of experimentally verified proteins. We identified motifs frequently occurring in each type of presequence showing specific patterns associated with their amino acid composition, and investigated their position within the presequence. We also compared motif patterns among different taxonomic groups and identified taxon-specific features, providing some evolutionary insights. Considering the functional relevance and many practical applications of targeting peptides and AMPs, we believe that our analyses will prove useful for their design, and better understanding of protein import mechanism and presequence evolution.
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Affiliation(s)
- Katarzyna Sidorczuk
- Department of Bioinformatics and Genomics, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Paweł Mackiewicz
- Department of Bioinformatics and Genomics, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Filip Pietluch
- Department of Bioinformatics and Genomics, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland
| | - Przemysław Gagat
- Department of Bioinformatics and Genomics, Faculty of Biotechnology, University of Wrocław, Wrocław, Poland.
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20
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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: 9] [Impact Index Per Article: 9.0] [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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21
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Fung TS, Chakrabarti R, Higgs HN. The multiple links between actin and mitochondria. Nat Rev Mol Cell Biol 2023; 24:651-667. [PMID: 37277471 PMCID: PMC10528321 DOI: 10.1038/s41580-023-00613-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2023] [Indexed: 06/07/2023]
Abstract
Actin plays many well-known roles in cells, and understanding any specific role is often confounded by the overlap of multiple actin-based structures in space and time. Here, we review our rapidly expanding understanding of actin in mitochondrial biology, where actin plays multiple distinct roles, exemplifying the versatility of actin and its functions in cell biology. One well-studied role of actin in mitochondrial biology is its role in mitochondrial fission, where actin polymerization from the endoplasmic reticulum through the formin INF2 has been shown to stimulate two distinct steps. However, roles for actin during other types of mitochondrial fission, dependent on the Arp2/3 complex, have also been described. In addition, actin performs functions independent of mitochondrial fission. During mitochondrial dysfunction, two distinct phases of Arp2/3 complex-mediated actin polymerization can be triggered. First, within 5 min of dysfunction, rapid actin assembly around mitochondria serves to suppress mitochondrial shape changes and to stimulate glycolysis. At a later time point, at more than 1 h post-dysfunction, a second round of actin polymerization prepares mitochondria for mitophagy. Finally, actin can both stimulate and inhibit mitochondrial motility depending on the context. These motility effects can either be through the polymerization of actin itself or through myosin-based processes, with myosin 19 being an important mitochondrially attached myosin. Overall, distinct actin structures assemble in response to diverse stimuli to affect specific changes to mitochondria.
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Affiliation(s)
- Tak Shun Fung
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA
- Department of Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Rajarshi Chakrabarti
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA
- MitoCare Center, Department of Pathology and Genomic Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Henry N Higgs
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover, NH, USA.
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22
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Tong L, Rao J, Yang C, Xu J, Lu Y, Zhang Y, Cang X, Xie S, Mao J, Jiang P. Mutational burden of XPNPEP3 leads to defects in mitochondrial complex I and cilia in NPHPL1. iScience 2023; 26:107446. [PMID: 37599822 PMCID: PMC10432713 DOI: 10.1016/j.isci.2023.107446] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 05/29/2023] [Accepted: 07/18/2023] [Indexed: 08/22/2023] Open
Abstract
Nephronophthisis-like nephropathy-1 (NPHPL1) is a rare ciliopathy, caused by mutations of XPNPEP3. Despite a well-described monogenic etiology, the pathogenesis of XPNPEP3 associated with mitochondrial and ciliary function remains elusive. Here, we identified novel compound heterozygous mutations in NPHPL1 patients with renal lesion only or with extra bone cysts together. Patient-derived lymphoblasts carrying c.634G>A and c.761G>T together exhibit elevated mitochondrial XPNPEP3 levels via the reduction of mRNA degradation, leading to mitochondrial dysfunction in both urine tubular epithelial cells and lymphoblasts from patient. Mitochondrial XPNPEP3 was co-immunoprecipitated with respiratory chain complex I and was required for the stability and activity of complex I. Deletion of Xpnpep3 in mice resulted in lower activity of complex I, elongated primary cilium, and predisposition to tubular dilation and fibrosis under stress. Our findings provide valuable insights into the mitochondrial functions involved in the pathogenesis of NPHP.
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Affiliation(s)
- Lingxiao Tong
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
| | - Jia Rao
- Department of Nephrology, Children’s Hospital of Fudan University, National Pediatric Medical Center of China, Shanghai, China
| | - Chenxi Yang
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Jie Xu
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
| | - Yijun Lu
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Yuchen Zhang
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaohui Cang
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
| | - Shanshan Xie
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
| | - Jianhua Mao
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Zhejiang Key Laboratory for Neonatal Diseases, The Children’s Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Pingping Jiang
- Department of Nephrology, The Children’s Hospital, Zhejiang University School of Medicine and National Clinical Research Center for Child Health, Hangzhou, China
- Department of Human Genetics, Zhejiang University School of Medicine, Hangzhou, China
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23
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Lear SK, Nunez JA, Shipman SL. A High-Throughput Colocalization Pipeline for Quantification of Mitochondrial Targeting across Different Protein Types. ACS Synth Biol 2023; 12:2498-2504. [PMID: 37506292 PMCID: PMC10561668 DOI: 10.1021/acssynbio.3c00349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Efficient metabolic engineering and the development of mitochondrial therapeutics often rely upon the specific and strong import of foreign proteins into mitochondria. Fusing a protein to a mitochondria-bound signal peptide is a common method to localize proteins to mitochondria, but this strategy is not universally effective, with particular proteins empirically failing to localize. To help overcome this barrier, this work develops a generalizable and open-source framework to design proteins for mitochondrial import and quantify their specific localization. This Python-based pipeline quantitatively assesses the colocalization of different proteins previously used for precise genome editing in a high-throughput manner to reveal signal peptide-protein combinations that localize well in mitochondria.
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Affiliation(s)
- Sierra K Lear
- Gladstone Institute of Data Science and Biotechnology, San Francisco, California 94158, United States
- Graduate Program in Bioengineering, University of California, San Francisco and Berkeley, California 94720, United States
| | - Jose A Nunez
- Department of Mechanical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Seth L Shipman
- Gladstone Institute of Data Science and Biotechnology, San Francisco, California 94158, United States
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California 94143, United States
- Chan Zuckerberg Biohub - San Francisco, San Francisco, California 94158, United States
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24
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Metzger MB, Scales JL, Grant GA, Molnar AE, Loncarek J, Weissman AM. Differential sensitivity of the yeast Lon protease Pim1p to impaired mitochondrial respiration. J Biol Chem 2023; 299:104937. [PMID: 37331598 PMCID: PMC10359500 DOI: 10.1016/j.jbc.2023.104937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/20/2023] Open
Abstract
Mitochondria are essential organelles whose proteome is well protected by regulated protein degradation and quality control. While the ubiquitin-proteasome system can monitor mitochondrial proteins that reside at the mitochondrial outer membrane or are not successfully imported, resident proteases generally act on proteins within mitochondria. Herein, we assess the degradative pathways for mutant forms of three mitochondrial matrix proteins (mas1-1HA, mas2-11HA, and tim44-8HA) in Saccharomyces cerevisiae. The degradation of these proteins is strongly impaired by loss of either the matrix AAA-ATPase (m-AAA) (Afg3p/Yta12p) or Lon (Pim1p) protease. We determine that these mutant proteins are all bona fide Pim1p substrates whose degradation is also blocked in respiratory-deficient "petite" yeast cells, such as in cells lacking m-AAA protease subunits. In contrast, matrix proteins that are substrates of the m-AAA protease are not affected by loss of respiration. The failure to efficiently remove Pim1p substrates in petite cells has no evident relationship to Pim1p maturation, localization, or assembly. However, Pim1p's autoproteolysis is intact, and its overexpression restores substrate degradation, indicating that Pim1p retains some functionality in petite cells. Interestingly, chemical perturbation of mitochondria with oligomycin similarly prevents degradation of Pim1p substrates. Our results demonstrate that Pim1p activity is highly sensitive to mitochondrial perturbations such as loss of respiration or drug treatment in a manner that we do not observe with other proteases.
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Affiliation(s)
- Meredith B Metzger
- Cancer Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA.
| | - Jessica L Scales
- Cancer Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Garis A Grant
- Cancer Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Abigail E Molnar
- Cancer Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Jadranka Loncarek
- Cancer Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Allan M Weissman
- Cancer Innovation Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA.
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25
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Zong S, Wu Y, Li W, You Q, Peng Q, Wang C, Wan P, Bai T, Ma Y, Sun B, Qiao J. SARS-CoV-2 Nsp8 induces mitophagy by damaging mitochondria. Virol Sin 2023; 38:520-530. [PMID: 37156297 PMCID: PMC10163945 DOI: 10.1016/j.virs.2023.05.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023] Open
Abstract
Autophagy plays an important role in the interaction between viruses and host cells. SARS-CoV-2 infection can disrupt the autophagy process in target cells. However, the precise molecular mechanism is still unknown. In this study, we discovered that the Nsp8 of SARS-CoV-2 could cause an increasing accumulation of autophagosomes by preventing the fusion of autophagosomes and lysosomes. From further investigation, we found that Nsp8 was present on mitochondria and can damage mitochondria to initiate mitophagy. The results of experiments with immunofluorescence revealed that Nsp8 induced incomplete mitophagy. Moreover, both domains of Nsp8 orchestrated their function during Nsp8-induced mitophagy, in which the N-terminal domain colocalized with mitochondria and the C-terminal domain induced auto/mitophagy. This novel finding expands our understanding of the function of Nsp8 in promoting mitochondrial damage and inducing incomplete mitophagy, which helps us to understand the etiology of COVID-19 as well as open up new pathways for creating SARS-CoV-2 treatment methods.
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Affiliation(s)
- Shan Zong
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China
| | - Yan Wu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Weiling Li
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China
| | - Qiang You
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China
| | - Qian Peng
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China
| | - Chenghai Wang
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China
| | - Pin Wan
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China
| | - Tao Bai
- Division of Gastroenterology, Tongji Medical College, Hua Zhong University of Science and Technology, Wuhan, 430030, China
| | - Yanling Ma
- Department of Respiratory and Critical Care Medicine, Hubei Province Clinical Research Center for Major Respiratory Diseases, NHC Key Laboratory of Pulmonary Diseases, Union Hospital, Tongji Medical College, Hua Zhong University of Science and Technology, Wuhan, 430030, China
| | - Binlian Sun
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China.
| | - Jialu Qiao
- Wuhan Institute of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, 430056, China; Hubei Key Laboratory of Wudang Local Chinese Medicine Research, Hubei University of Medicine, Shiyan, 442000, China.
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26
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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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27
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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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28
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Wu N, Li F, Yang W, Du WW, Awan FM, Zhang C, Lyu J, Misir S, Zeng K, Eshaghi E, Yang BB. Silencing mouse circular RNA circSlc8a1 by circular antisense cA-circSlc8a1 induces cardiac hepatopathy. Mol Ther 2023; 31:1688-1704. [PMID: 36245125 PMCID: PMC10277841 DOI: 10.1016/j.ymthe.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/16/2022] [Accepted: 10/14/2022] [Indexed: 11/08/2022] Open
Abstract
Circular RNAs (circRNAs) are a group of non-coding RNAs with a unique circular structure generated by back-splicing. It is acknowledged that circRNAs play critical roles in cardiovascular diseases. However, functional studies of circRNAs were impeded due to lack of effective in vivo silencing approaches. Since most circRNAs are produced by protein-coding transcripts, gene editing typically affects the coding activity of the parental genes. In this study, we developed a circular antisense RNA (cA-circSlc8a1) that could silence the highly expressed circRNA circSlc8a1 in the mouse heart but not its parental Slc8a1 linear mRNA. Transgenic cA-circSlc8a1 mice developed congestive heart failure resulting in a significant increase in the body weight secondary to peripheral edema and congestive hepatopathy. To further test the role of circSlc8a1, we generated transgenic mice overexpressing circSlc8a1 and observed a protective effect of circSlc8a1 in a pressure overload model. Mechanistically, we found that circSlc8a1 translocated into mitochondria to drive ATP synthesis. While establishing a transgenic murine model for antisense-mediated circRNA silencing without interfering with the parental linear RNA, our finding revealed the essential role of circSlc8a1 in maintaining heart function and may lay the groundwork of using the circular antisense RNA as a potential gene therapy approach for cardiovascular diseases.
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Affiliation(s)
- Nan Wu
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Feiya Li
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Weining Yang
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - William W Du
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Faryal Mehwish Awan
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada; Department of Medical Lab Technology, the University of Haripur (UOH), Haripur, Pakistan
| | - Chao Zhang
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Juanjuan Lyu
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Sema Misir
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Kaixuan Zeng
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Esra Eshaghi
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada
| | - Burton B Yang
- Sunnybrook Research Institute, Toronto, ON M4N3M5, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.
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29
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Simakin P, Koch C, Herrmann JM. A modular cloning (MoClo) toolkit for reliable intracellular protein targeting in the yeast Saccharomyces cerevisiae. MICROBIAL CELL (GRAZ, AUSTRIA) 2023; 10:78-87. [PMID: 37009624 PMCID: PMC10054711 DOI: 10.15698/mic2023.04.794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 04/04/2023]
Abstract
Modular Cloning (MoClo) allows the combinatorial assembly of plasmids from standardized genetic parts without the need of error-prone PCR reactions. It is a very powerful strategy which enables highly flexible expression patterns without the need of repetitive cloning procedures. In this study, we describe an advanced MoClo toolkit that is designed for the baker's yeast Saccharomyces cerevisiae and optimized for the targeting of proteins of interest to specific cellular compartments. Comparing different targeting sequences, we developed signals to direct proteins with high specificity to the different mitochondrial subcompartments, such as the matrix and the intermembrane space (IMS). Furthermore, we optimized the subcellular targeting by controlling expression levels using a collection of different promoter cassettes; the MoClo strategy allows it to generate arrays of expression plasmids in parallel to optimize gene expression levels and reliable targeting for each given protein and cellular compartment. Thus, the MoClo strategy enables the generation of protein-expressing yeast plasmids that accurately target proteins of interest to various cellular compartments.
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Affiliation(s)
- Pavel Simakin
- Cell Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
- # Both authors contributed equally
| | - Christian Koch
- Cell Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
- # Both authors contributed equally
| | - Johannes M. Herrmann
- Cell Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
- * Corresponding Author: Johannes M. Herrmann, Cell Biology, University of Kaiserslautern, Erwin-Schrödinger-Strasse 13, 67663 Kaiserslautern, Germany; Phone: +49 6312052406; E-mail:
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30
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Echtenkamp FJ, Ishida R, Rivera-Marquez GM, Maisiak M, Johnson OT, Shrimp JH, Sinha A, Ralph SJ, Nisbet I, Cherukuri MK, Gestwicki JE, Neckers LM. Mitoribosome sensitivity to HSP70 inhibition uncovers metabolic liabilities of castration-resistant prostate cancer. PNAS NEXUS 2023; 2:pgad115. [PMID: 37091547 PMCID: PMC10118397 DOI: 10.1093/pnasnexus/pgad115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/07/2023] [Accepted: 03/23/2023] [Indexed: 04/05/2023]
Abstract
The androgen receptor is a key regulator of prostate cancer and the principal target of current prostate cancer therapies collectively termed androgen deprivation therapies. Insensitivity to these drugs is a hallmark of progression to a terminal disease state termed castration-resistant prostate cancer. Therefore, novel therapeutic options that slow progression of castration-resistant prostate cancer and combine effectively with existing agents are in urgent need. We show that JG-98, an allosteric inhibitor of HSP70, re-sensitizes castration-resistant prostate cancer to androgen deprivation drugs by targeting mitochondrial HSP70 (HSPA9) to suppress aerobic respiration. Rather than impacting androgen receptor stability as previously described, JG-98's primary effect is inhibition of mitochondrial translation, leading to disruption of electron transport chain activity. Although functionally distinct from HSPA9 inhibition, direct inhibition of the electron transport chain with a complex I or II inhibitor creates a similar physiological state capable of re-sensitizing castration-resistant prostate cancer to androgen deprivation therapies. These data identify a significant role for HspA9 in mitochondrial ribosome function and highlight an actionable metabolic vulnerability of castration-resistant prostate cancer.
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Affiliation(s)
- Frank J Echtenkamp
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Ryo Ishida
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Genesis M Rivera-Marquez
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Marisa Maisiak
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Oleta T Johnson
- Department of Pharmaceutical Chemistry and the Institute for Neurodegenerative Disease, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Jonathan H Shrimp
- Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Arnav Sinha
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | | | - Ian Nisbet
- Cancure Ltd,Broadbeach, Queensland 4218, Australia
| | - Murali Krishna Cherukuri
- Biophysics Section, Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry and the Institute for Neurodegenerative Disease, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Leonard M Neckers
- Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
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31
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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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32
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Busch JD, Fielden LF, Pfanner N, Wiedemann N. Mitochondrial protein transport: Versatility of translocases and mechanisms. Mol Cell 2023; 83:890-910. [PMID: 36931257 DOI: 10.1016/j.molcel.2023.02.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 03/17/2023]
Abstract
Biogenesis of mitochondria requires the import of approximately 1,000 different precursor proteins into and across the mitochondrial membranes. Mitochondria exhibit a wide variety of mechanisms and machineries for the translocation and sorting of precursor proteins. Five major import pathways that transport proteins to their functional intramitochondrial destination have been elucidated; these pathways range from the classical amino-terminal presequence-directed pathway to pathways using internal or even carboxy-terminal targeting signals in the precursors. Recent studies have provided important insights into the structural organization of membrane-embedded preprotein translocases of mitochondria. A comparison of the different translocases reveals the existence of at least three fundamentally different mechanisms: two-pore-translocase, β-barrel switching, and transport cavities open to the lipid bilayer. In addition, translocases are physically engaged in dynamic interactions with respiratory chain complexes, metabolite transporters, quality control factors, and machineries controlling membrane morphology. Thus, mitochondrial preprotein translocases are integrated into multi-functional networks of mitochondrial and cellular machineries.
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Affiliation(s)
- Jakob D Busch
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Laura F Fielden
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, 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.
| | - Nils Wiedemann
- 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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Lionaki E, Gkikas I, Tavernarakis N. Mitochondrial protein import machinery conveys stress signals to the cytosol and beyond. Bioessays 2023; 45:e2200160. [PMID: 36709422 DOI: 10.1002/bies.202200160] [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: 08/16/2022] [Revised: 12/14/2022] [Accepted: 01/02/2023] [Indexed: 01/30/2023]
Abstract
Mitochondria hold diverse and pivotal roles in fundamental processes that govern cell survival, differentiation, and death, in addition to organismal growth, maintenance, and aging. The mitochondrial protein import system is a major contributor to mitochondrial biogenesis and lies at the crossroads between mitochondrial and cellular homeostasis. Recent findings highlight the mitochondrial protein import system as a signaling hub, receiving inputs from other cellular compartments and adjusting its function accordingly. Impairment of protein import, in a physiological, or disease context, elicits adaptive responses inside and outside mitochondria. In this review, we discuss recent developments, relevant to the mechanisms of mitochondrial protein import regulation, with a particular focus on quality control, proteostatic and metabolic cellular responses, triggered upon impairment of mitochondrial protein import.
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Affiliation(s)
- Eirini Lionaki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Crete, Greece
| | - Ilias Gkikas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Crete, Greece
- Department of Biology, School of Sciences and Engineering, University of Crete, Heraklion, Crete, Greece
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Crete, Greece
- Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece
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34
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Taskin AA, Moretti DN, Vögtle FN, Meisinger C. Isolation and Quality Control of Yeast Mitochondria. Methods Mol Biol 2023; 2615:41-55. [PMID: 36807783 DOI: 10.1007/978-1-0716-2922-2_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The isolation of organelles devoid of other cellular compartments is crucial for studying organellar proteomes and the localization of newly identified proteins, as well as for assessing specific organellar functions. Here, we describe a protocol for the isolation of crude and highly pure mitochondria from Saccharomyces cerevisiae and provide methods for testing the functional integrity of the isolated organelles.
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Affiliation(s)
- Asli Aras Taskin
- 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
| | - Daiana Nerina Moretti
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - F Nora Vögtle
- 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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35
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Schulte U, den Brave F, Haupt A, Gupta A, Song J, Müller CS, Engelke J, Mishra S, Mårtensson C, Ellenrieder L, Priesnitz C, Straub SP, Doan KN, Kulawiak B, Bildl W, Rampelt H, Wiedemann N, Pfanner N, Fakler B, Becker T. Mitochondrial complexome reveals quality-control pathways of protein import. Nature 2023; 614:153-159. [PMID: 36697829 PMCID: PMC9892010 DOI: 10.1038/s41586-022-05641-w] [Citation(s) in RCA: 47] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 12/09/2022] [Indexed: 01/26/2023]
Abstract
Mitochondria have crucial roles in cellular energetics, metabolism, signalling and quality control1-4. They contain around 1,000 different proteins that often assemble into complexes and supercomplexes such as respiratory complexes and preprotein translocases1,3-7. The composition of the mitochondrial proteome has been characterized1,3,5,6; however, the organization of mitochondrial proteins into stable and dynamic assemblies is poorly understood for major parts of the proteome1,4,7. Here we report quantitative mapping of mitochondrial protein assemblies using high-resolution complexome profiling of more than 90% of the yeast mitochondrial proteome, termed MitCOM. An analysis of the MitCOM dataset resolves >5,200 protein peaks with an average of six peaks per protein and demonstrates a notable complexity of mitochondrial protein assemblies with distinct appearance for respiration, metabolism, biogenesis, dynamics, regulation and redox processes. We detect interactors of the mitochondrial receptor for cytosolic ribosomes, of prohibitin scaffolds and of respiratory complexes. The identification of quality-control factors operating at the mitochondrial protein entry gate reveals pathways for preprotein ubiquitylation, deubiquitylation and degradation. Interactions between the peptidyl-tRNA hydrolase Pth2 and the entry gate led to the elucidation of a constitutive pathway for the removal of preproteins. The MitCOM dataset-which is accessible through an interactive profile viewer-is a comprehensive resource for the identification, organization and interaction of mitochondrial machineries and pathways.
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Affiliation(s)
- Uwe Schulte
- Institute of Physiology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Fabian den Brave
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Alexander Haupt
- Institute of Physiology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Arushi Gupta
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jiyao Song
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Catrin S Müller
- Institute of Physiology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jeannine Engelke
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Swadha Mishra
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Christoph Mårtensson
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- MTIP, Basel, Switzerland
| | - Lars Ellenrieder
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Novartis, Basel, Switzerland
| | - Chantal Priesnitz
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sebastian P Straub
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
- Sanofi-Aventis (Suisse), Vernier, Switzerland
| | - Kim Nguyen Doan
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Bogusz Kulawiak
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Wolfgang Bildl
- Institute of Physiology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Heike Rampelt
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Nils Wiedemann
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Nikolaus Pfanner
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
| | - Bernd Fakler
- Institute of Physiology, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
- Center for Basics in NeuroModulation, Freiburg, Germany.
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
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36
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Krämer L, Dalheimer N, Räschle M, Storchová Z, Pielage J, Boos F, Herrmann JM. MitoStores: chaperone-controlled protein granules store mitochondrial precursors in the cytosol. EMBO J 2023; 42:e112309. [PMID: 36704946 PMCID: PMC10068336 DOI: 10.15252/embj.2022112309] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 01/05/2023] [Accepted: 01/12/2023] [Indexed: 01/28/2023] Open
Abstract
Hundreds of nucleus-encoded mitochondrial precursor proteins are synthesized in the cytosol and imported into mitochondria in a post-translational manner. However, the early processes associated with mitochondrial protein targeting remain poorly understood. Here, we show that in Saccharomyces cerevisiae, the cytosol has the capacity to transiently store mitochondrial matrix-destined precursors in dedicated deposits that we termed MitoStores. Competitive inhibition of mitochondrial protein import via clogging of import sites greatly enhances the formation of MitoStores, but they also form during physiological cell growth on nonfermentable carbon sources. MitoStores are enriched for a specific subset of nucleus-encoded mitochondrial proteins, in particular those containing N-terminal mitochondrial targeting sequences. Our results suggest that MitoStore formation suppresses the toxic potential of aberrantly accumulating mitochondrial precursor proteins and is controlled by the heat shock proteins Hsp42 and Hsp104. Thus, the cytosolic protein quality control system plays an active role during the early stages of mitochondrial protein targeting through the coordinated and localized sequestration of mitochondrial precursor proteins.
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Affiliation(s)
- Lena Krämer
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Niko Dalheimer
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Markus Räschle
- Molecular Genetics, University of Kaiserslautern, Kaiserslautern, Germany
| | - Zuzana Storchová
- Molecular Genetics, University of Kaiserslautern, Kaiserslautern, Germany
| | - Jan Pielage
- Zoology and Neurobiology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Felix Boos
- Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
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37
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Bayne AN, Dong J, Amiri S, Farhan SMK, Trempe JF. MTSviewer: A database to visualize mitochondrial targeting sequences, cleavage sites, and mutations on protein structures. PLoS One 2023; 18:e0284541. [PMID: 37093842 PMCID: PMC10124841 DOI: 10.1371/journal.pone.0284541] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 04/02/2023] [Indexed: 04/25/2023] Open
Abstract
Mitochondrial dysfunction is implicated in a wide array of human diseases ranging from neurodegenerative disorders to cardiovascular defects. The coordinated localization and import of proteins into mitochondria are essential processes that ensure mitochondrial homeostasis. The localization and import of most mitochondrial proteins are driven by N-terminal mitochondrial targeting sequences (MTS's), which interact with import machinery and are removed by the mitochondrial processing peptidase (MPP). The recent discovery of internal MTS's-those which are distributed throughout a protein and act as import regulators or secondary MPP cleavage sites-has expanded the role of both MTS's and MPP beyond conventional N-terminal regulatory pathways. Still, the global mutational landscape of MTS's remains poorly characterized, both from genetic and structural perspectives. To this end, we have integrated a variety of tools into one harmonized R/Shiny database called MTSviewer (https://neurobioinfo.github.io/MTSvieweR/), which combines MTS predictions, cleavage sites, genetic variants, pathogenicity predictions, and N-terminomics data with structural visualization using AlphaFold models of human and yeast mitochondrial proteomes. Using MTSviewer, we profiled all MTS-containing proteins across human and yeast mitochondrial proteomes and provide multiple case studies to highlight the utility of this database.
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Affiliation(s)
- Andrew N Bayne
- Department of Pharmacology & Therapeutics and Centre de Recherche en Biologie Structurale, McGill University, Montréal, Quebec, Canada
| | - Jing Dong
- Department of Pharmacology & Therapeutics and Centre de Recherche en Biologie Structurale, McGill University, Montréal, Quebec, Canada
| | - Saeid Amiri
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montréal, Quebec, Canada
| | - Sali M K Farhan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montréal, Quebec, Canada
- Department of Human Genetics, McGill University, Montréal, Quebec, Canada
| | - Jean-François Trempe
- Department of Pharmacology & Therapeutics and Centre de Recherche en Biologie Structurale, McGill University, Montréal, Quebec, Canada
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38
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Soldatov VO, Kubekina MV, Skorkina MY, Belykh AE, Egorova TV, Korokin MV, Pokrovskiy MV, Deykin AV, Angelova PR. Current advances in gene therapy of mitochondrial diseases. J Transl Med 2022; 20:562. [PMID: 36471396 PMCID: PMC9724384 DOI: 10.1186/s12967-022-03685-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/04/2022] [Indexed: 12/12/2022] Open
Abstract
Mitochondrial diseases (MD) are a heterogeneous group of multisystem disorders involving metabolic errors. MD are characterized by extremely heterogeneous symptoms, ranging from organ-specific to multisystem dysfunction with different clinical courses. Most primary MD are autosomal recessive but maternal inheritance (from mtDNA), autosomal dominant, and X-linked inheritance is also known. Mitochondria are unique energy-generating cellular organelles designed to survive and contain their own unique genetic coding material, a circular mtDNA fragment of approximately 16,000 base pairs. The mitochondrial genetic system incorporates closely interacting bi-genomic factors encoded by the nuclear and mitochondrial genomes. Understanding the dynamics of mitochondrial genetics supporting mitochondrial biogenesis is especially important for the development of strategies for the treatment of rare and difficult-to-diagnose diseases. Gene therapy is one of the methods for correcting mitochondrial disorders.
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Affiliation(s)
- Vladislav O Soldatov
- Core Facility Centre, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia.
- Department of Pharmacology and Clinical Pharmacology, Belgorod State National Research University, Belgorod, Russia.
- Laboratory of Genome Editing for Biomedicine and Animal Health, Belgorod State National Research University, Belgorod, Russia.
| | - Marina V Kubekina
- Core Facility Centre, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Marina Yu Skorkina
- Department of Biochemistry, Belgorod State National Research University, Belgorod, Russia
- Laboratory of Genome Editing for Biomedicine and Animal Health, Belgorod State National Research University, Belgorod, Russia
| | - Andrei E Belykh
- Dioscuri Centre for Metabolic Diseases, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Tatiana V Egorova
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Mikhail V Korokin
- Department of Pharmacology and Clinical Pharmacology, Belgorod State National Research University, Belgorod, Russia
| | - Mikhail V Pokrovskiy
- Department of Pharmacology and Clinical Pharmacology, Belgorod State National Research University, Belgorod, Russia
| | - Alexey V Deykin
- Department of Pharmacology and Clinical Pharmacology, Belgorod State National Research University, Belgorod, Russia
- Laboratory of Genome Editing for Biomedicine and Animal Health, Belgorod State National Research University, Belgorod, Russia
| | - Plamena R Angelova
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
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Yasuhara T, Nakai T, Fujiki Y. Purification and characterization of protease M, a yeast mitochondrial nucleotide-stimulated metal protease: Its identification as CYM1 gene product, a mitochondrial presequence peptidase. J Biochem 2022; 172:277-292. [PMID: 35997162 DOI: 10.1093/jb/mvac066] [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: 03/30/2022] [Accepted: 08/12/2022] [Indexed: 11/14/2022] Open
Abstract
A chelator-sensitive protease in the mitochondrial matrix of the yeast, Saccharomyces cerevisiae (Biochem. Biophys. Res. Commun. 144, 277, 1987), was purified and characterized. The purified enzyme, termed protease M, specifically hydrolyzes peptide substrates on the N-side of the paired basic residues. When mastoparan was used as substrate, it cleaved Ala8-Leu9 and Lys11-Lys12 bonds as well as the N-side of Lys11-Lys12 residues. Nucleotide triphosphates stimulated the activity 3-fold at 2.5 mM. The genomic DNA sequence showed that Protease M was gene product of CYM1 known as mitochondrial presequence protease homologue in S. cerevisiae, encoding a 989-amino-acid long precursor protein. The N-terminal sequence of the purified enzyme indicated that protease M has 16-residue signal sequence and the "mature" protein consists of 973 amino acids with a molecular mass of 110 kDa. Protease M contained consensus sequence motifs of ATP-binding site very near the carboxyl terminus. The alignment of the two ATP-binding motifs is an inverted version of the common alignment. Gene-disruption of the enzyme generates mixed subunits in tetrameric MnSOD formed with 23-kDa mature and 24-kDa partial presequence-containing subunits. This report describes newly identified enzyme properties of the CYM1 gene product, protease M, and abnormal MnSOD complex formation of the disruption mutant.
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Affiliation(s)
- Toshimasa Yasuhara
- Innovation Division, Co-Creation Bureau, Osaka University, 2-8 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Toshiki Nakai
- Radioisotope Research Center, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Yukio Fujiki
- Institute of Rheological Functions of Food-Kyushu University Collaboration Program, Kyushu University, Fukuoka 812-8582, Japan; Graduate School of Science, University of Hyogo, Hyogo 678-1297, Japan
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40
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Garrido C, Wollman FA, Lafontaine I. The evolutionary history of peptidases involved in the processing of Organelle-Targeting Peptides. Genome Biol Evol 2022; 14:6618273. [PMID: 35758251 PMCID: PMC9291397 DOI: 10.1093/gbe/evac101] [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] [Accepted: 06/23/2022] [Indexed: 11/25/2022] Open
Abstract
Most of the proteins present in mitochondria and chloroplasts, the organelles acquired via endosymbiotic events, are encoded in the nucleus and translated into the cytosol. Most of such nuclear-encoded proteins are specifically recognized via an N-terminal-encoded targeting peptide (TP) and imported into the organelles via a translocon machinery. Once imported, the TP is degraded by a succession of cleavage steps ensured by dedicated peptidases. Here, we retrace the evolution of the families of the mitochondrial processing peptidase (MPP), stromal processing peptidase (SPP), presequence protease (PreP), and organellar oligo-peptidase (OOP) that play a central role in TP processing and degradation across the tree of life. Their bacterial distributions are widespread but patchy, revealing unsurprisingly complex history of lateral transfers among bacteria. We provide evidence for the eukaryotic acquisition of MPP, OOP, and PreP by lateral gene transfers from bacteria at the time of the mitochondrial endosymbiosis. We show that the acquisition of SPP and of a second copy of OOP and PreP at the time of the chloroplast endosymbiosis was followed by a differential loss of one PreP paralog in photosynthetic eukaryotes. We identified some contrasting sequence conservations between bacterial and eukaryotic homologs that could reflect differences in the functional context of their peptidase activity. The close vicinity of the eukaryotic peptidases MPP and OOP to those of several bacterial pathogens, showing antimicrobial resistance, supports a scenario where such bacteria were instrumental in the establishment of the proteolytic pathway for TP degradation in organelles. The evidence for their role in the acquisition of PreP is weaker, and none is observed for SPP, although it cannot be excluded by the present study.
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Affiliation(s)
- Clotilde Garrido
- UMR7141, Institut de Biologie Physico-Chimique (CNRS/Sorbonne Université), 13 Rue Pierre et Marie Curie, 75005 Paris, France
| | - Francis André Wollman
- UMR7141, Institut de Biologie Physico-Chimique (CNRS/Sorbonne Université), 13 Rue Pierre et Marie Curie, 75005 Paris, France
| | - Ingrid Lafontaine
- UMR7141, Institut de Biologie Physico-Chimique (CNRS/Sorbonne Université), 13 Rue Pierre et Marie Curie, 75005 Paris, France
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41
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Genome-Wide Analysis of the Peptidase M24 Superfamily in Triticum aestivum Demonstrates That TaM24-9 Is Involved in Abiotic Stress Response. Int J Mol Sci 2022; 23:ijms23136904. [PMID: 35805912 PMCID: PMC9266489 DOI: 10.3390/ijms23136904] [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: 03/30/2022] [Revised: 06/14/2022] [Accepted: 06/17/2022] [Indexed: 02/04/2023] Open
Abstract
The peptidase M24 (Metallopeptidase 24, M24) superfamily is essential for plant growth, stress response, and pathogen defense. At present, there are few systematic reports on the identification and classification of members of the peptidase M24 proteins superfamily in wheat. In this work, we identified 53 putative candidate TaM24 genes. According to the protein sequences characteristics, these members can be roughly divided into three subfamilies: I, II, III. Most TaM24 genes are complex with multiple exons, and the motifs are relatively conserved in each sub-group. Through chromosome mapping analysis, we found that the 53 genes were unevenly distributed on 19 wheat chromosomes (except 3A and 3D), of which 68% were in triads. Analysis of gene duplication events showed that 62% of TaM24 genes in wheat came from fragment duplication events, and there were no tandem duplication events to amplify genes. Analysis of the promoter sequences of TaM24 genes revealed that cis-acting elements were rich in response elements to drought, osmotic stress, ABA, and MeJA. We also studied the expression of TaM24 in wheat tissues at developmental stages and abiotic stress. Then we selected TaM24-9 as the target for further analysis. The results showed that TaM24-9 genes strengthened the drought and salt tolerance of plants. Overall, our analysis showed that members of the peptidase M24 genes may participate in the abiotic stress response and provided potential gene resources for improving wheat resistance.
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42
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Payá-Tormo L, Coroian D, Martín-Muñoz S, Badalyan A, Green RT, Veldhuizen M, Jiang X, López-Torrejón G, Balk J, Seefeldt LC, Burén S, Rubio LM. A colorimetric method to measure in vitro nitrogenase functionality for engineering nitrogen fixation. Sci Rep 2022; 12:10367. [PMID: 35725884 PMCID: PMC9209457 DOI: 10.1038/s41598-022-14453-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 06/06/2022] [Indexed: 11/09/2022] Open
Abstract
Biological nitrogen fixation (BNF) is the reduction of N2 into NH3 in a group of prokaryotes by an extremely O2-sensitive protein complex called nitrogenase. Transfer of the BNF pathway directly into plants, rather than by association with microorganisms, could generate crops that are less dependent on synthetic nitrogen fertilizers and increase agricultural productivity and sustainability. In the laboratory, nitrogenase activity is commonly determined by measuring ethylene produced from the nitrogenase-dependent reduction of acetylene (ARA) using a gas chromatograph. The ARA is not well suited for analysis of large sample sets nor easily adapted to automated robotic determination of nitrogenase activities. Here, we show that a reduced sulfonated viologen derivative (S2Vred) assay can replace the ARA for simultaneous analysis of isolated nitrogenase proteins using a microplate reader. We used the S2Vred to screen a library of NifH nitrogenase components targeted to mitochondria in yeast. Two NifH proteins presented properties of great interest for engineering of nitrogen fixation in plants, namely NifM independency, to reduce the number of genes to be transferred to the eukaryotic host; and O2 resistance, to expand the half-life of NifH iron-sulfur cluster in a eukaryotic cell. This study established that NifH from Dehalococcoides ethenogenes did not require NifM for solubility, [Fe-S] cluster occupancy or functionality, and that NifH from Geobacter sulfurreducens was more resistant to O2 exposure than the other NifH proteins tested. It demonstrates that nitrogenase components with specific biochemical properties such as a wider range of O2 tolerance exist in Nature, and that their identification should be an area of focus for the engineering of nitrogen-fixing crops.
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Affiliation(s)
- Lucía Payá-Tormo
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain
| | - Diana Coroian
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain
| | - Silvia Martín-Muñoz
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain
| | - Artavazd Badalyan
- Department of Chemistry and Biochemistry, Utah State University, Logan, UT, USA
| | - Robert T Green
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich, NR4 7UH, UK
| | - Marcel Veldhuizen
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain
| | - Xi Jiang
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain
| | - Gema López-Torrejón
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain
| | - Janneke Balk
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich, NR4 7UH, UK
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Lance C Seefeldt
- Department of Chemistry and Biochemistry, Utah State University, Logan, UT, USA
| | - Stefan Burén
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain.
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain.
| | - Luis M Rubio
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), Campus de Montegancedo UPM, Crta M-40 km 38 Pozuelo de Alarcón, 28223, Madrid, Spain.
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040, Madrid, Spain.
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43
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Ford HC, Allen WJ, Pereira GC, Liu X, Dillingham MS, Collinson I. Towards a molecular mechanism underlying mitochondrial protein import through the TOM and TIM23 complexes. eLife 2022; 11:75426. [PMID: 35674314 PMCID: PMC9255969 DOI: 10.7554/elife.75426] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 06/07/2022] [Indexed: 12/27/2022] Open
Abstract
Nearly all mitochondrial proteins need to be targeted for import from the cytosol. For the majority, the first port of call is the translocase of the outer membrane (TOM complex), followed by a procession of alternative molecular machines, conducting transport to their final destination. The pre-sequence translocase of the inner membrane (TIM23-complex) imports proteins with cleavable pre-sequences. Progress in understanding these transport mechanisms has been hampered by the poor sensitivity and time resolution of import assays. However, with the development of an assay based on split NanoLuc luciferase, we can now explore this process in greater detail. Here, we apply this new methodology to understand how ∆ψ and ATP hydrolysis, the two main driving forces for import into the matrix, contribute to the transport of pre-sequence-containing precursors (PCPs) with varying properties. Notably, we found that two major rate-limiting steps define PCP import time: passage of PCP across the outer membrane and initiation of inner membrane transport by the pre-sequence - the rates of which are influenced by PCP size and net charge. The apparent distinction between transport through the two membranes (passage through TOM is substantially complete before PCP-TIM engagement) is in contrast with the current view that import occurs through TOM and TIM in a single continuous step. Our results also indicate that PCPs spend very little time in the TIM23 channel - presumably rapid success or failure of import is critical for maintenance of mitochondrial fitness.
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Affiliation(s)
- Holly C Ford
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - William J Allen
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Gonçalo C Pereira
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Xia Liu
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | | | - Ian Collinson
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
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44
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Freitas AV, Herb JT, Pan M, Chen Y, Gucek M, Jin T, Xu H. Generation of a mitochondrial protein compendium in Dictyostelium discoideum. iScience 2022; 25:104332. [PMID: 35602934 PMCID: PMC9118663 DOI: 10.1016/j.isci.2022.104332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/29/2022] [Accepted: 04/26/2022] [Indexed: 11/20/2022] Open
Abstract
The social ameba Dictyostelium discoideum has emerged as a powerful model to study mitochondrial genetics and bioenergetics. However, a comprehensive inventory of mitochondrial proteins that is critical to understanding mitochondrial processes has yet to be curated. Here, we utilized high-throughput multiplexed protein quantitation and homology analyses to generate a high-confidence mitochondrial protein compendium consisting of 936 proteins. Our proteomic approach, which utilizes mass spectrometry in combination with mathematical modeling, was validated through mitochondrial targeting sequence prediction and live-cell imaging. Our final compendium consists of 936 proteins. Nearly, a third of D. discoideum mitochondrial proteins do not have homologs in humans, budding yeasts, or an ancestral alphaproteobacteria. Additionally, we leverage our compendium to highlight the complexity of metabolic reprogramming during starvation-induced development. Our compendium lays a foundation to investigate mitochondrial processes that are unique in ameba and to understand the functions of conserved mitochondrial proteins in D. discoideum.
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Affiliation(s)
- Anna V. Freitas
- National Heart, Lung and Blood Institute, National Institute of Health, Bethesda, MD 20892, USA
| | - Jake T. Herb
- National Heart, Lung and Blood Institute, National Institute of Health, Bethesda, MD 20892, USA
| | - Miao Pan
- National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, MD 20852, USA
| | - Yong Chen
- National Heart, Lung and Blood Institute, National Institute of Health, Bethesda, MD 20892, USA
| | - Marjan Gucek
- National Heart, Lung and Blood Institute, National Institute of Health, Bethesda, MD 20892, USA
| | - Tian Jin
- National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, MD 20852, USA
| | - Hong Xu
- National Heart, Lung and Blood Institute, National Institute of Health, Bethesda, MD 20892, USA
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45
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Proteolytic regulation of mitochondrial oxidative phosphorylation components in plants. Biochem Soc Trans 2022; 50:1119-1132. [PMID: 35587610 PMCID: PMC9246333 DOI: 10.1042/bst20220195] [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: 02/09/2022] [Revised: 04/07/2022] [Accepted: 05/03/2022] [Indexed: 11/28/2022]
Abstract
Mitochondrial function relies on the homeostasis and quality control of their proteome, including components of the oxidative phosphorylation (OXPHOS) pathway that generates energy in form of ATP. OXPHOS subunits are under constant exposure to reactive oxygen species due to their oxidation-reduction activities, which consequently make them prone to oxidative damage, misfolding, and aggregation. As a result, quality control mechanisms through turnover and degradation are required for maintaining mitochondrial activity. Degradation of OXPHOS subunits can be achieved through proteomic turnover or modular degradation. In this review, we present multiple protein degradation pathways in plant mitochondria. Specifically, we focus on the intricate turnover of OXPHOS subunits, prior to protein import via cytosolic proteasomal degradation and post import and assembly via intra-mitochondrial proteolysis involving multiple AAA+ proteases. Together, these proteolytic pathways maintain the activity and homeostasis of OXPHOS components.
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46
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Jishi A, Qi X. Altered Mitochondrial Protein Homeostasis and Proteinopathies. Front Mol Neurosci 2022; 15:867935. [PMID: 35571369 PMCID: PMC9095842 DOI: 10.3389/fnmol.2022.867935] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/25/2022] [Indexed: 12/13/2022] Open
Abstract
Increasing evidence implicates mitochondrial dysfunction as key in the development and progression of various forms of neurodegeneration. The multitude of functions carried out by mitochondria necessitates a tight regulation of protein import, dynamics, and turnover; this regulation is achieved via several, often overlapping pathways that function at different levels. The development of several major neurodegenerative diseases is associated with dysregulation of these pathways, and growing evidence suggests direct interactions between some pathogenic proteins and mitochondria. When these pathways are compromised, so is mitochondrial function, and the resulting deficits in bioenergetics, trafficking, and mitophagy can exacerbate pathogenic processes. In this review, we provide an overview of the regulatory mechanisms employed by mitochondria to maintain protein homeostasis and discuss the failure of these mechanisms in the context of several major proteinopathies.
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Affiliation(s)
| | - Xin Qi
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, United States
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47
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Avendaño-Monsalve MC, Mendoza-Martínez AE, Ponce-Rojas JC, Poot-Hernández AC, Rincón-Heredia R, Funes S. Positively charged amino acids at the N terminus of select mitochondrial proteins mediate early recognition by import proteins αβ'-NAC and Sam37. J Biol Chem 2022; 298:101984. [PMID: 35487246 PMCID: PMC9136113 DOI: 10.1016/j.jbc.2022.101984] [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: 10/30/2021] [Revised: 04/16/2022] [Accepted: 04/19/2022] [Indexed: 11/04/2022] Open
Abstract
A major challenge in eukaryotic cells is the proper distribution of nuclear-encoded proteins to the correct organelles. For a subset of mitochondrial proteins, a signal sequence at the N terminus (matrix-targeting sequence [MTS]) is recognized by protein complexes to ensure their proper translocation into the organelle. However, the early steps of mitochondrial protein targeting remain undeciphered. The cytosolic chaperone nascent polypeptide–associated complex (NAC), which in yeast is represented as the two different heterodimers αβ-NAC and αβ′-NAC, has been proposed to be involved during the early steps of mitochondrial protein targeting. We have previously described that the mitochondrial outer membrane protein Sam37 interacts with αβ′-NAC and together promote the import of specific mitochondrial precursor proteins. In this work, we aimed to detect the region in the MTS of mitochondrial precursors relevant for their recognition by αβ′-NAC during their sorting to the mitochondria. We used targeting signals of different mitochondrial proteins (αβ′-NAC-dependent Oxa1 and αβ′-NAC-independent Mdm38) and fused them to GFP to study their intracellular localization by biochemical and microscopy methods, and in addition followed their import kinetics in vivo. Our results reveal the presence of a positively charged amino acid cluster in the MTS of select mitochondrial precursors, such as Oxa1 and Fum1, which are crucial for their recognition by αβ′-NAC. Furthermore, we explored the presence of this cluster at the N terminus of the mitochondrial proteome and propose a set of precursors whose proper localization depends on both αβ′-NAC and Sam37.
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Affiliation(s)
- Maria Clara Avendaño-Monsalve
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Cd.Mx., Mexico
| | - Ariann E Mendoza-Martínez
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Cd.Mx., Mexico
| | - José Carlos Ponce-Rojas
- Department of Molecular, Cellular, and Developmental Biology, University of California at Santa Barbara, Santa Barbara, California, USA
| | - Augusto César Poot-Hernández
- Unidad de Bioinformática y Manejo de la Información, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Cd.Mx., Mexico
| | - Ruth Rincón-Heredia
- Unidad de Imagenología, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Cd.Mx., Mexico
| | - Soledad Funes
- Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Cd.Mx., Mexico.
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48
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Eldeeb MA, Thomas RA, Ragheb MA, Fallahi A, Fon EA. Mitochondrial quality control in health and in Parkinson's disease. Physiol Rev 2022; 102:1721-1755. [PMID: 35466694 DOI: 10.1152/physrev.00041.2021] [Citation(s) in RCA: 86] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
As a central hub for cellular metabolism and intracellular signalling, the mitochondrion is a pivotal organelle, dysfunction of which has been linked to several human diseases including neurodegenerative disorders, and in particular Parkinson's disease. An inherent challenge that mitochondria face is the continuous exposure to diverse stresses which increase their likelihood of dysregulation. In response, eukaryotic cells have evolved sophisticated quality control mechanisms to monitor, identify, repair and/or eliminate abnormal or misfolded proteins within the mitochondrion and/or the dysfunctional mitochondrion itself. Chaperones identify unstable or otherwise abnormal conformations in mitochondrial proteins and can promote their refolding to recover their correct conformation and stability. However, if repair is not possible, the abnormal protein is selectively degraded to prevent potentially damaging interactions with other proteins or its oligomerization into toxic multimeric complexes. The autophagic-lysosomal system and the ubiquitin-proteasome system mediate the selective and targeted degradation of such abnormal or misfolded protein species. Mitophagy (a specific kind of autophagy) mediates the selective elimination of dysfunctional mitochondria, in order to prevent the deleterious effects the dysfunctional organelles within the cell. Despite our increasing understanding of the molecular responses toward dysfunctional mitochondria, many key aspects remain relatively poorly understood. Herein, we review the emerging mechanisms of mitochondrial quality control including quality control strategies coupled to mitochondrial import mechanisms. In addition, we review the molecular mechanisms regulating mitophagy with an emphasis on the regulation of PINK1/PARKIN-mediated mitophagy in cellular physiology and in the context of Parkinson's disease cell biology.
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Affiliation(s)
- Mohamed A Eldeeb
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Rhalena A Thomas
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Mohamed A Ragheb
- Chemistry Department (Biochemistry Division), Faculty of Science, Cairo University, Giza, Egypt
| | - Armaan Fallahi
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Edward A Fon
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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49
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Fessler E, Krumwiede L, Jae LT. DELE1 tracks perturbed protein import and processing in human mitochondria. Nat Commun 2022; 13:1853. [PMID: 35388015 PMCID: PMC8986780 DOI: 10.1038/s41467-022-29479-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 03/11/2022] [Indexed: 12/15/2022] Open
Abstract
Protein homeostatic control of mitochondria is key to age-related diseases and organismal decline. However, it is unknown how the diverse types of stress experienced by mitochondria can be integrated and appropriately responded to in human cells. Here we identify perturbations in the ancient conserved processes of mitochondrial protein import and processing as sources of DELE1 activation: DELE1 is continuously sorted across both mitochondrial membranes into the matrix and detects different types of perturbations along the way. DELE1 molecules in transit can become licensed for mitochondrial release and stress signaling through proteolytic removal of N-terminal sorting signals. Import defects that occur at the mitochondrial surface allow DELE1 precursors to bind and activate downstream factor HRI without the need for cleavage. Genome-wide genetics reveal that DELE1 additionally responds to compromised presequence processing by the matrix proteases PITRM1 and MPP, which are mutated in neurodegenerative diseases. These mechanisms rationalize DELE1-dependent mitochondrial stress integration in the human system and may inform future therapies of neuropathies.
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Affiliation(s)
- Evelyn Fessler
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377, Munich, Germany.
| | - Luisa Krumwiede
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377, Munich, Germany
| | - Lucas T Jae
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377, Munich, Germany.
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50
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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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