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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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2
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Chang YT, Barad BA, Rahmani H, Zid BM, Grotjahn DA. Cytoplasmic ribosomes on mitochondria alter the local membrane environment for protein import. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.17.604013. [PMID: 39071314 PMCID: PMC11275913 DOI: 10.1101/2024.07.17.604013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Most of the mitochondria proteome is nuclear-encoded, synthesized by cytoplasmic ribosomes, and targeted to mitochondria post-translationally. However, a subset of mitochondrial-targeted proteins is imported co-translationally, although the molecular mechanisms governing this process remain unclear. We employ cellular cryo-electron tomography to visualize interactions between cytoplasmic ribosomes and mitochondria in Saccharomyces cerevisiae. We use surface morphometrics tools to identify a subset of ribosomes optimally oriented on mitochondrial membranes for protein import. This allows us to establish the first subtomogram average structure of a cytoplasmic ribosome on the surface of the mitochondria in the native cellular context, which showed three distinct connections with the outer mitochondrial membrane surrounding the peptide exit tunnel. Further, this analysis demonstrated that cytoplasmic ribosomes primed for mitochondrial protein import cluster on the outer mitochondrial membrane at sites of local constrictions of the outer and inner mitochondrial membrane. Overall, our study reveals the architecture and the spatial organization of cytoplasmic ribosomes at the mitochondrial surface, providing a native cellular context to define the mechanisms that mediate efficient mitochondrial co-translational protein import.
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Affiliation(s)
- Ya-Ting Chang
- Department of Integrative Structural and Computation Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Benjamin A Barad
- Department of Integrative Structural and Computation Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
- Department of Chemical Physiology and Biochemistry, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Hamidreza Rahmani
- Department of Integrative Structural and Computation Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Brian M Zid
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Danielle A Grotjahn
- Department of Integrative Structural and Computation Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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3
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Vlasova AD, Bukhalovich SM, Bagaeva DF, Polyakova AP, Ilyinsky NS, Nesterov SV, Tsybrov FM, Bogorodskiy AO, Zinovev EV, Mikhailov AE, Vlasov AV, Kuklin AI, Borshchevskiy VI, Bamberg E, Uversky VN, Gordeliy VI. Intracellular microbial rhodopsin-based optogenetics to control metabolism and cell signaling. Chem Soc Rev 2024; 53:3327-3349. [PMID: 38391026 DOI: 10.1039/d3cs00699a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Microbial rhodopsin (MRs) ion channels and pumps have become invaluable optogenetic tools for neuroscience as well as biomedical applications. Recently, MR-optogenetics expanded towards subcellular organelles opening principally new opportunities in optogenetic control of intracellular metabolism and signaling via precise manipulations of organelle ion gradients using light. This new optogenetic field expands the opportunities for basic and medical studies of cancer, cardiovascular, and metabolic disorders, providing more detailed and accurate control of cell physiology. This review summarizes recent advances in studies of the cellular metabolic processes and signaling mediated by optogenetic tools targeting mitochondria, endoplasmic reticulum (ER), lysosomes, and synaptic vesicles. Finally, we discuss perspectives of such an optogenetic approach in both fundamental and applied research.
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Affiliation(s)
- Anastasiia D Vlasova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Siarhei M Bukhalovich
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Diana F Bagaeva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Aleksandra P Polyakova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Nikolay S Ilyinsky
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Semen V Nesterov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Fedor M Tsybrov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Andrey O Bogorodskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Egor V Zinovev
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Anatolii E Mikhailov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Alexey V Vlasov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Alexander I Kuklin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Valentin I Borshchevskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Ernst Bamberg
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Vladimir N Uversky
- Department of Molecular Medicine and Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
| | - Valentin I Gordeliy
- Institut de Biologie Structurale Jean-Pierre Ebel, Université Grenoble Alpes-Commissariat à l'Energie Atomique et aux Energies Alternatives-CNRS, 38027 Grenoble, France.
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4
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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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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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Tahmaz I, Shahmoradi Ghahe S, Stasiak M, Liput KP, Jonak K, Topf U. Prefoldin 2 contributes to mitochondrial morphology and function. BMC Biol 2023; 21:193. [PMID: 37697385 PMCID: PMC10496292 DOI: 10.1186/s12915-023-01695-y] [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: 02/27/2023] [Accepted: 08/31/2023] [Indexed: 09/13/2023] Open
Abstract
BACKGROUND Prefoldin is an evolutionarily conserved co-chaperone of the tailless complex polypeptide 1 ring complex (TRiC)/chaperonin containing tailless complex 1 (CCT). The prefoldin complex consists of six subunits that are known to transfer newly produced cytoskeletal proteins to TRiC/CCT for folding polypeptides. Prefoldin function was recently linked to the maintenance of protein homeostasis, suggesting a more general function of the co-chaperone during cellular stress conditions. Prefoldin acts in an adenosine triphosphate (ATP)-independent manner, making it a suitable candidate to operate during stress conditions, such as mitochondrial dysfunction. Mitochondrial function depends on the production of mitochondrial proteins in the cytosol. Mechanisms that sustain cytosolic protein homeostasis are vital for the quality control of proteins destined for the organelle and such mechanisms among others include chaperones. RESULTS We analyzed consequences of the loss of prefoldin subunits on the cell proliferation and survival of Saccharomyces cerevisiae upon exposure to various cellular stress conditions. We found that prefoldin subunits support cell growth under heat stress. Moreover, prefoldin facilitates the growth of cells under respiratory growth conditions. We showed that mitochondrial morphology and abundance of some respiratory chain complexes was supported by the prefoldin 2 (Pfd2/Gim4) subunit. We also found that Pfd2 interacts with Tom70, a receptor of mitochondrial precursor proteins that are targeted into mitochondria. CONCLUSIONS Our findings link the cytosolic prefoldin complex to mitochondrial function. Loss of the prefoldin complex subunit Pfd2 results in adaptive cellular responses on the proteome level under physiological conditions suggesting a continuous need of Pfd2 for maintenance of cellular homeostasis. Within this framework, Pfd2 might support mitochondrial function directly as part of the cytosolic quality control system of mitochondrial proteins or indirectly as a component of the protein homeostasis network.
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Affiliation(s)
- Ismail Tahmaz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Somayeh Shahmoradi Ghahe
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Monika Stasiak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Kamila P Liput
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Katarzyna Jonak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Ulrike Topf
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland.
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Campos Y, Rodriguez-Enriquez R, Palacios G, Van de Vlekkert D, Qiu X, Weesner J, Gomero E, Demmers J, Bertorini T, Opferman JT, Grosveld GC, d'Azzo A. Mitochondrial proteostasis mediated by CRL5 Ozz and Alix maintains skeletal muscle function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.11.548601. [PMID: 37503076 PMCID: PMC10369959 DOI: 10.1101/2023.07.11.548601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
High energy-demanding tissues, such as skeletal muscle, require mitochondrial proteostasis to function properly. Two quality-control mechanisms, the ubiquitin proteasome system (UPS) and the release of mitochondria-derived vesicles, safeguard mitochondrial proteostasis. However, whether these processes interact is unknown. Here we show that the E3 ligase CRL5 Ozz , a member of the UPS, and its substrate Alix control the mitochondrial concentration of Slc25A4, a solute carrier that is essential for ATP production. The mitochondria in Ozz -/- or Alix -/- skeletal muscle share overt morphologic alterations (they are supernumerary, swollen, and dysmorphic) and have abnormal metabolomic profiles. We found that CRL5 Ozz ubiquitinates Slc25A4 and promotes its proteasomal degradation, while Alix facilitates SLC25A4 loading into exosomes destined for lysosomal destruction. The loss of Ozz or Alix offsets steady-state levels of Slc25A4, which disturbs mitochondrial metabolism and alters muscle fiber composition. These findings reveal hitherto unknown regulatory functions of Ozz and Alix in mitochondrial proteostasis.
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8
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Chen S, Allen G, Panasenko OO, Collart MA. Not4-dependent targeting of MMF1 mRNA to mitochondria limits its expression via ribosome pausing, Egd1 ubiquitination, Caf130, no-go-decay and autophagy. Nucleic Acids Res 2023; 51:5022-5039. [PMID: 37094076 PMCID: PMC10250226 DOI: 10.1093/nar/gkad299] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 04/11/2023] [Indexed: 04/26/2023] Open
Abstract
The Ccr4-Not complex is a conserved multi protein complex with diverse roles in the mRNA life cycle. Recently we determined that the Not1 and Not4 subunits of Ccr4-Not inversely regulate mRNA solubility and thereby impact dynamics of co-translation events. One mRNA whose solubility is limited by Not4 is MMF1 encoding a mitochondrial matrix protein. In this work we uncover a mechanism that limits MMF1 overexpression and depends upon its co-translational targeting to the mitochondria. We have named this mechanism Mito-ENCay. This mechanism relies on Not4 promoting ribosome pausing during MMF1 translation, and hence the co-translational docking of the MMF1 mRNA to mitochondria via the mitochondrial targeting sequence of the Mmf1 nascent chain, the Egd1 chaperone, the Om14 mitochondrial outer membrane protein and the co-translational import machinery. Besides co-translational Mitochondrial targeting, Mito-ENCay depends upon Egd1 ubiquitination by Not4, the Caf130 subunit of the Ccr4-Not complex, the mitochondrial outer membrane protein Cis1, autophagy and no-go-decay.
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Affiliation(s)
- Siyu Chen
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Institute of Genetics and Genomics of Geneva, Geneva, Switzerland
| | - George Allen
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Institute of Genetics and Genomics of Geneva, Geneva, Switzerland
| | - Olesya O Panasenko
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Institute of Genetics and Genomics of Geneva, Geneva, Switzerland
| | - Martine A Collart
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Institute of Genetics and Genomics of Geneva, Geneva, Switzerland
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9
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Meurant S, Mauclet L, Dieu M, Arnould T, Eyckerman S, Renard P. Endogenous TOM20 Proximity Labeling: A Swiss-Knife for the Study of Mitochondrial Proteins in Human Cells. Int J Mol Sci 2023; 24:ijms24119604. [PMID: 37298552 DOI: 10.3390/ijms24119604] [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: 04/20/2023] [Revised: 05/24/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
Biotin-based proximity labeling approaches, such as BioID, have demonstrated their use for the study of mitochondria proteomes in living cells. The use of genetically engineered BioID cell lines enables the detailed characterization of poorly characterized processes such as mitochondrial co-translational import. In this process, translation is coupled to the translocation of the mitochondrial proteins, alleviating the energy cost typically associated with the post-translational import relying on chaperone systems. However, the mechanisms are still unclear with only few actors identified but none that have been described in mammals yet. We thus profiled the TOM20 proxisome using BioID, assuming that some of the identified proteins could be molecular actors of the co-translational import in human cells. The obtained results showed a high enrichment of RNA binding proteins close to the TOM complex. However, for the few selected candidates, we could not demonstrate a role in the mitochondrial co-translational import process. Nonetheless, we were able to demonstrate additional uses of our BioID cell line. Indeed, the experimental approach used in this study is thus proposed for the identification of mitochondrial co-translational import effectors and for the monitoring of protein entry inside mitochondria with a potential application in the prediction of mitochondrial protein half-life.
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Affiliation(s)
- Sébastien Meurant
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Lorris Mauclet
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Marc Dieu
- Mass Spectrometry Platform (MaSUN), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Thierry Arnould
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Sven Eyckerman
- VIB-UGent Center for Medical Biotechnology, VIB, 9000 Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
| | - Patricia Renard
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
- Mass Spectrometry Platform (MaSUN), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
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10
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Zgajnar N, Lagadari M, Gallo LI, Piwien-Pilipuk G, Galigniana MD. Mitochondrial-nuclear communication by FKBP51 shuttling. J Cell Biochem 2023. [PMID: 36815347 DOI: 10.1002/jcb.30386] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/24/2023] [Accepted: 02/03/2023] [Indexed: 02/24/2023]
Abstract
The HSP90-binding immunophilin FKBP51 is a soluble protein that shows high homology and structural similarity with FKBP52. Both immunophilins are functionally divergent and often show antagonistic actions. They were first described in steroid receptor complexes, their exchange in the complex being the earliest known event in steroid receptor activation upon ligand binding. In addition to steroid-related events, several pleiotropic actions of FKBP51 have emerged during the last years, ranging from cell differentiation and apoptosis to metabolic and psychiatric disorders. On the other hand, mitochondria play vital cellular roles in maintaining energy homeostasis, responding to stress conditions, and affecting cell cycle regulation, calcium signaling, redox homeostasis, and so forth. This is achieved by proteins that are encoded in both the nuclear genome and mitochondrial genes. This implies active nuclear-mitochondrial communication to maintain cell homeostasis. Such communication involves factors that regulate nuclear and mitochondrial gene expression affecting the synthesis and recruitment of mitochondrial and nonmitochondrial proteins, and/or changes in the functional state of the mitochondria itself, which enable mitochondria to recover from stress. FKBP51 has emerged as a serious candidate to participate in these regulatory roles since it has been unexpectedly found in mitochondria showing antiapoptotic effects. Such localization involves the tetratricopeptide repeats domains of the immunophilin and not its intrinsic enzymatic activity of peptidylprolyl-isomerase. Importantly, FKBP51 abandons the mitochondria and accumulates in the nucleus upon cell differentiation or during the onset of stress. Nuclear FKBP51 enhances the enzymatic activity of telomerase. The mitochondrial-nuclear trafficking is reversible, and certain situations such as viral infections promote the opposite trafficking, that is, FKBP51 abandons the nucleus and accumulates in mitochondria. In this article, we review the latest findings related to the mitochondrial-nuclear communication mediated by FKBP51 and speculate about the possible implications of this phenomenon.
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Affiliation(s)
- Nadia Zgajnar
- Instituto de Biología y Medicina Experimental (IBYME)/CONICET, Buenos Aires, Argentina
| | - Mariana Lagadari
- Instituto de Ciencia y Tecnología de Alimentos de Entre Ríos, Concordia, Argentina
| | - Luciana I Gallo
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFYBYNE)/CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Mario D Galigniana
- Instituto de Biología y Medicina Experimental (IBYME)/CONICET, Buenos Aires, Argentina
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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11
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de Teresa-Trueba I, Goetz SK, Mattausch A, Stojanovska F, Zimmerli CE, Toro-Nahuelpan M, Cheng DWC, Tollervey F, Pape C, Beck M, Diz-Muñoz A, Kreshuk A, Mahamid J, Zaugg JB. Convolutional networks for supervised mining of molecular patterns within cellular context. Nat Methods 2023; 20:284-294. [PMID: 36690741 PMCID: PMC9911354 DOI: 10.1038/s41592-022-01746-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 12/02/2022] [Indexed: 01/24/2023]
Abstract
Cryo-electron tomograms capture a wealth of structural information on the molecular constituents of cells and tissues. We present DeePiCt (deep picker in context), an open-source deep-learning framework for supervised segmentation and macromolecular complex localization in cryo-electron tomography. To train and benchmark DeePiCt on experimental data, we comprehensively annotated 20 tomograms of Schizosaccharomyces pombe for ribosomes, fatty acid synthases, membranes, nuclear pore complexes, organelles, and cytosol. By comparing DeePiCt to state-of-the-art approaches on this dataset, we show its unique ability to identify low-abundance and low-density complexes. We use DeePiCt to study compositionally distinct subpopulations of cellular ribosomes, with emphasis on their contextual association with mitochondria and the endoplasmic reticulum. Finally, applying pre-trained networks to a HeLa cell tomogram demonstrates that DeePiCt achieves high-quality predictions in unseen datasets from different biological species in a matter of minutes. The comprehensively annotated experimental data and pre-trained networks are provided for immediate use by the community.
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Affiliation(s)
- Irene de Teresa-Trueba
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,Present Address: Computer Science and Artificial Intelligence Lab, ENGIE Lab Crigen, Stains, France
| | - Sara K. Goetz
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.7700.00000 0001 2190 4373Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Alexander Mattausch
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.7700.00000 0001 2190 4373Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Frosina Stojanovska
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.7700.00000 0001 2190 4373Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Christian E. Zimmerli
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.419494.50000 0001 1018 9466Present Address: Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Mauricio Toro-Nahuelpan
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,Present Address: Santiago GmbH & Co. KG, Willich, Germany
| | - Dorothy W. C. Cheng
- grid.7700.00000 0001 2190 4373Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany ,grid.4709.a0000 0004 0495 846XCell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Fergus Tollervey
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.7700.00000 0001 2190 4373Collaboration for Joint PhD Degree between EMBL and Heidelberg University, Faculty of Biosciences, Heidelberg, Germany
| | - Constantin Pape
- grid.4709.a0000 0004 0495 846XCell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.7450.60000 0001 2364 4210Present Address: Institute for Computer Science, Universität Göttingen, Göttingen, Germany
| | - Martin Beck
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.4709.a0000 0004 0495 846XCell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.419494.50000 0001 1018 9466Present Address: Department of Molecular Sociology, Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Alba Diz-Muñoz
- grid.4709.a0000 0004 0495 846XCell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Anna Kreshuk
- grid.4709.a0000 0004 0495 846XCell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Julia Mahamid
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany. .,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
| | - Judith B. Zaugg
- grid.4709.a0000 0004 0495 846XStructural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany ,grid.4709.a0000 0004 0495 846XGenome Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
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12
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Uszczynska-Ratajczak B, Sugunan S, Kwiatkowska M, Migdal M, Carbonell-Sala S, Sokol A, Winata CL, Chacinska A. Profiling subcellular localization of nuclear-encoded mitochondrial gene products in zebrafish. Life Sci Alliance 2022; 6:6/1/e202201514. [PMID: 36283702 PMCID: PMC9595208 DOI: 10.26508/lsa.202201514] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/30/2022] [Accepted: 10/04/2022] [Indexed: 11/08/2022] Open
Abstract
Most mitochondrial proteins are encoded by nuclear genes, synthetized in the cytosol and targeted into the organelle. To characterize the spatial organization of mitochondrial gene products in zebrafish (Danio rerio), we sequenced RNA from different cellular fractions. Our results confirmed the presence of nuclear-encoded mRNAs in the mitochondrial fraction, which in unperturbed conditions, are mainly transcripts encoding large proteins with specific properties, like transmembrane domains. To further explore the principles of mitochondrial protein compartmentalization in zebrafish, we quantified the transcriptomic changes for each subcellular fraction triggered by the chchd4a -/- mutation, causing the disorders in the mitochondrial protein import. Our results indicate that the proteostatic stress further restricts the population of transcripts on the mitochondrial surface, allowing only the largest and the most evolutionary conserved proteins to be synthetized there. We also show that many nuclear-encoded mitochondrial transcripts translated by the cytosolic ribosomes stay resistant to the global translation shutdown. Thus, vertebrates, in contrast to yeast, are not likely to use localized translation to facilitate synthesis of mitochondrial proteins under proteostatic stress conditions.
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Affiliation(s)
- Barbara Uszczynska-Ratajczak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland .,Centre of New Technologies, University of Warsaw, Warsaw, Poland
| | - Sreedevi Sugunan
- ReMedy International Research Agenda Unit, University of Warsaw, Warsaw, Poland,International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Monika Kwiatkowska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland,Centre of New Technologies, University of Warsaw, Warsaw, Poland,International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Maciej Migdal
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Silvia Carbonell-Sala
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Anna Sokol
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany,Biomolecular Mass Spectrometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Cecilia L Winata
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Agnieszka Chacinska
- ReMedy International Research Agenda Unit, IMol Polish Academy of Sciences, Warsaw, Poland
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13
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Liu X, Hussain R, Mehmood K, Tang Z, Zhang H, Li Y. Mitochondrial-Endoplasmic Reticulum Communication-Mediated Oxidative Stress and Autophagy. BIOMED RESEARCH INTERNATIONAL 2022; 2022:6459585. [PMID: 36164446 PMCID: PMC9509228 DOI: 10.1155/2022/6459585] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/18/2022] [Accepted: 08/22/2022] [Indexed: 12/03/2022]
Abstract
Oxidative stress is an imbalance between free radicals and the antioxidant system causing overgeneration of free radicals (oxygen-containing molecules) ultimately leading to oxidative damage in terms of lipid peroxidation, protein denaturation, and DNA mutation. Oxidative stress can activate autophagy to alleviate oxidative damage and maintain normal physiological activities of cells by degrading damaged organelles or local cytoplasm. When oxidative stress is not eliminated by autophagy, it activates the apoptosis cascade. This review provides a brief summary of mitochondrial-endoplasmic reticulum communication-mediated oxidative stress and autophagy. Mitochondria and endoplasmic reticulum being important organelles in cells are directly or indirectly connected to each other through mitochondria-associated endoplasmic reticulum membranes and jointly regulate oxidative stress and autophagy. The reactive oxygen species (ROS) produced by the mitochondrial respiratory chain are the main inducers of oxidative stress. Damaged mitochondria can be effectively cleared by the process of mitophagy mediated by PINK1/parkin pathway, Nix/BNIP3 pathways, and FUNDC1 pathway, avoiding excessive ROS production. However, the mechanism of mitochondrial-endoplasmic reticulum communication in the regulation of oxidative stress and autophagy is rarely known. For this reason, this review explores the mutual connection of mitochondria and endoplasmic reticulum in mediating oxidative stress and autophagy through ROS and Ca2+ and aims to provide part of the theoretical basis for alleviating oxidative stress through autophagy mediated by mitochondrial-endoplasmic reticulum communication.
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Affiliation(s)
- Xiaoqing Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Riaz Hussain
- Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, 63100, Pakistan
| | - Khalid Mehmood
- Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, 63100, Pakistan
| | - Zhaoxin Tang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Hui Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Ying Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
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14
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15
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Abstract
The human brain consumes five orders of magnitude more energy than the sun by unit of mass and time. This staggering bioenergetic cost serves mostly synaptic transmission and actin cytoskeleton dynamics. The peak of both brain bioenergetic demands and the age of onset for neurodevelopmental disorders is approximately 5 years of age. This correlation suggests that defects in the machinery that provides cellular energy would be causative and/or consequence of neurodevelopmental disorders. We explore this hypothesis from the perspective of the machinery required for the synthesis of the electron transport chain, an ATP-producing and NADH-consuming enzymatic cascade. The electron transport chain is constituted by nuclear- and mitochondrial-genome-encoded subunits. These subunits are synthesized by the 80S and the 55S ribosomes, which are segregated to the cytoplasm and the mitochondrial matrix, correspondingly. Mitochondrial protein synthesis by the 55S ribosome is the rate-limiting step in the synthesis of electron transport chain components, suggesting that mitochondrial protein synthesis is a bottleneck for tissues with high bionergetic demands. We discuss genetic defects in the human nuclear and mitochondrial genomes that affect these protein synthesis machineries and cause a phenotypic spectrum spanning autism spectrum disorders to neurodegeneration during neurodevelopment. We propose that dysregulated mitochondrial protein synthesis is a chief, yet understudied, causative mechanism of neurodevelopmental and behavioral disorders.
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16
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Rodrigues T, Piccirillo S, Magi S, Preziuso A, Dos Santos Ramos V, Serfilippi T, Orciani M, Maciel Palacio Alvarez M, Luis Dos Santos Tersariol I, Amoroso S, Lariccia V. Control of Ca 2+ and metabolic homeostasis by the Na +/Ca 2+ exchangers (NCXs) in health and disease. Biochem Pharmacol 2022; 203:115163. [PMID: 35803319 DOI: 10.1016/j.bcp.2022.115163] [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: 04/01/2022] [Revised: 06/30/2022] [Accepted: 07/01/2022] [Indexed: 11/16/2022]
Abstract
Spatial and temporal control of calcium (Ca2+) levels is essential for the background rhythms and responses of living cells to environmental stimuli. Whatever other regulators a given cellular activity may have, localized and wider scale Ca2+ events (sparks, transients, and waves) are hierarchical determinants of fundamental processes such as cell contraction, excitability, growth, metabolism and survival. Different cell types express specific channels, pumps and exchangers to efficiently generate and adapt Ca2+ patterns to cell requirements. The Na+/Ca2+ exchangers (NCXs) in particular contribute to Ca2+ homeostasis by buffering intracellular Ca2+ loads according to the electrochemical gradients of substrate ions - i.e., Ca2+ and sodium (Na+) - and under a dynamic control of redundant regulatory processes. An interesting feature of NCX emerges from the strict relationship that connects transporter activity with cell metabolism: on the one hand NCX operates under constant control of ATP-dependent regulatory processes, on the other hand the ion fluxes generated through NCX provide mechanistic support for the Na+-driven uptake of glutamate and Ca2+ influx to fuel mitochondrial respiration. Proof of concept evidence highlights therapeutic potential of preserving a timed and balanced NCX activity in a growing rate of diseases (including excitability, neurodegenerative, and proliferative disorders) because of an improved ability of stressed cells to safely maintain ion gradients and mitochondrial bioenergetics. Here, we will summarize and review recent works that have focused on the pathophysiological roles of NCXs in balancing the two-way relationship between Ca2+ signals and metabolism.
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Affiliation(s)
- Tiago Rodrigues
- Center for Natural and Human Sciences (CCNH), Federal University of ABC (UFABC), Santo André, SP, Brazil.
| | - Silvia Piccirillo
- Department of Biomedical Sciences and Public Health, School of Medicine, University "Politecnica delle Marche", Ancona, Italy.
| | - Simona Magi
- Department of Biomedical Sciences and Public Health, School of Medicine, University "Politecnica delle Marche", Ancona, Italy.
| | - Alessandra Preziuso
- Department of Biomedical Sciences and Public Health, School of Medicine, University "Politecnica delle Marche", Ancona, Italy.
| | - Vyctória Dos Santos Ramos
- Interdisciplinary Center for Biochemistry Investigation (CIIB), University of Mogi das Cruzes (UMC), Mogi das Cruzes, SP, Brazil
| | - Tiziano Serfilippi
- Department of Biomedical Sciences and Public Health, School of Medicine, University "Politecnica delle Marche", Ancona, Italy.
| | - Monia Orciani
- Department of Clinical and Molecular Sciences, Histology, University "Politecnica delle Marche", Ancona, Italy.
| | - Marcela Maciel Palacio Alvarez
- Department of Biochemistry, São Paulo School of Medicine, Federal University of São Paulo (Unifesp) São Paulo, SP, Brazil
| | | | - Salvatore Amoroso
- Department of Biomedical Sciences and Public Health, School of Medicine, University "Politecnica delle Marche", Ancona, Italy.
| | - Vincenzo Lariccia
- Department of Biomedical Sciences and Public Health, School of Medicine, University "Politecnica delle Marche", Ancona, Italy.
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17
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Nikolaeva NS, Yandulova EY, Aleksandrova YR, Starikov AS, Neganova ME. The Role of a Pathological Interaction between β-amyloid and Mitochondria in the Occurrence and Development of Alzheimer's Disease. Acta Naturae 2022; 14:19-34. [PMID: 36348714 PMCID: PMC9611857 DOI: 10.32607/actanaturae.11723] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 07/05/2022] [Indexed: 11/20/2022] Open
Abstract
Alzheimer's disease (AD) is one of the most common neurodegenerative diseases in existence. It is characterized by an impaired cognitive function that is due to a progressive loss of neurons in the brain. Extracellular β-amyloid (Aβ) plaques are the main pathological features of the disease. In addition to abnormal protein aggregation, increased mitochondrial fragmentation, altered expression of the genes involved in mitochondrial biogenesis, disruptions in the ER-mitochondria interaction, and mitophagy are observed. Reactive oxygen species are known to affect Aβ expression and aggregation. In turn, oligomeric and aggregated Aβ cause mitochondrial disorders. In this review, we summarize available knowledge about the pathological effects of Aβ on mitochondria and the potential molecular targets associated with proteinopathy and mitochondrial dysfunction for the pharmacological treatment of Alzheimer's disease.
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Affiliation(s)
- N. S. Nikolaeva
- Federal State Budgetary Institution of Science Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Chernogolovka, 142432 Russia
| | - E. Yu. Yandulova
- Federal State Budgetary Institution of Science Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Chernogolovka, 142432 Russia
| | - Yu. R. Aleksandrova
- Federal State Budgetary Institution of Science Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Chernogolovka, 142432 Russia
| | - A. S. Starikov
- Federal State Budgetary Institution of Science Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Chernogolovka, 142432 Russia
| | - M. E. Neganova
- Federal State Budgetary Institution of Science Institute of Physiologically Active Compounds of the Russian Academy of Sciences, Chernogolovka, 142432 Russia
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18
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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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19
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Chemotherapy Resistance: Role of Mitochondrial and Autophagic Components. Cancers (Basel) 2022; 14:cancers14061462. [PMID: 35326612 PMCID: PMC8945922 DOI: 10.3390/cancers14061462] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/10/2022] [Accepted: 03/10/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Chemotherapy resistance is a common occurrence during cancer treatment that cancer researchers are attempting to understand and overcome. Mitochondria are a crucial intracellular signaling core that are becoming important determinants of numerous aspects of cancer genesis and progression, such as metabolic reprogramming, metastatic capability, and chemotherapeutic resistance. Mitophagy, or selective autophagy of mitochondria, can influence both the efficacy of tumor chemotherapy and the degree of drug resistance. Regardless of the fact that mitochondria are well-known for coordinating ATP synthesis from cellular respiration in cellular bioenergetics, little is known its mitophagy regulation in chemoresistance. Recent advancements in mitochondrial research, mitophagy regulatory mechanisms, and their implications for our understanding of chemotherapy resistance are discussed in this review. Abstract Cancer chemotherapy resistance is one of the most critical obstacles in cancer therapy. One of the well-known mechanisms of chemotherapy resistance is the change in the mitochondrial death pathways which occur when cells are under stressful situations, such as chemotherapy. Mitophagy, or mitochondrial selective autophagy, is critical for cell quality control because it can efficiently break down, remove, and recycle defective or damaged mitochondria. As cancer cells use mitophagy to rapidly sweep away damaged mitochondria in order to mediate their own drug resistance, it influences the efficacy of tumor chemotherapy as well as the degree of drug resistance. Yet despite the importance of mitochondria and mitophagy in chemotherapy resistance, little is known about the precise mechanisms involved. As a consequence, identifying potential therapeutic targets by analyzing the signal pathways that govern mitophagy has become a vital research goal. In this paper, we review recent advances in mitochondrial research, mitophagy control mechanisms, and their implications for our understanding of chemotherapy resistance.
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20
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Genge MG, Mokranjac D. Coordinated Translocation of Presequence-Containing Precursor Proteins Across Two Mitochondrial Membranes: Knowns and Unknowns of How TOM and TIM23 Complexes Cooperate With Each Other. Front Physiol 2022; 12:806426. [PMID: 35069261 PMCID: PMC8770809 DOI: 10.3389/fphys.2021.806426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/03/2021] [Indexed: 11/23/2022] Open
Abstract
The vast majority of mitochondrial proteins are encoded in the nuclear genome and synthesized on cytosolic ribosomes as precursor proteins with specific mitochondrial targeting signals. Mitochondrial targeting signals are very diverse, however, about 70% of mitochondrial proteins carry cleavable, N-terminal extensions called presequences. These amphipathic helices with one positively charged and one hydrophobic surface target proteins to the mitochondrial matrix with the help of the TOM and TIM23 complexes in the outer and inner membranes, respectively. Translocation of proteins across the two mitochondrial membranes does not take place independently of each other. Rather, in the intermembrane space, where the two complexes meet, components of the TOM and TIM23 complexes form an intricate network of protein-protein interactions that mediates initially transfer of presequences and then of the entire precursor proteins from the outer to the inner mitochondrial membrane. In this Mini Review, we summarize our current understanding of how the TOM and TIM23 complexes cooperate with each other and highlight some of the future challenges and unresolved questions in the field.
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Affiliation(s)
| | - Dejana Mokranjac
- Biozentrum — Department of Cell Biology, LMU Munich, Munich, Germany
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21
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Schäfer JA, Bozkurt S, Michaelis JB, Klann K, Münch C. Global mitochondrial protein import proteomics reveal distinct regulation by translation and translocation machinery. Mol Cell 2021; 82:435-446.e7. [PMID: 34847359 PMCID: PMC8791276 DOI: 10.1016/j.molcel.2021.11.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 09/09/2021] [Accepted: 11/02/2021] [Indexed: 01/03/2023]
Abstract
Most mitochondrial proteins are translated in the cytosol and imported into mitochondria. Mutations in the mitochondrial protein import machinery cause human pathologies. However, a lack of suitable tools to measure protein uptake across the mitochondrial proteome has prevented the identification of specific proteins affected by import perturbation. Here, we introduce mePRODmt, a pulsed-SILAC based proteomics approach that includes a booster signal to increase the sensitivity for mitochondrial proteins selectively, enabling global dynamic analysis of endogenous mitochondrial protein uptake in cells. We applied mePRODmt to determine protein uptake kinetics and examined how inhibitors of mitochondrial import machineries affect protein uptake. Monitoring changes in translation and uptake upon mitochondrial membrane depolarization revealed that protein uptake was extensively modulated by the import and translation machineries via activation of the integrated stress response. Strikingly, uptake changes were not uniform, with subsets of proteins being unaffected or decreased due to changes in translation or import capacity. Proteomics approach to quantify protein uptake into mitochondria Determination of protein uptake rates for >700 mitochondrial proteins Characterization of differential protein uptake changes during mitochondrial stress Protein translation and translocation integrate to change protein uptake
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Affiliation(s)
- Jasmin Adriana Schäfer
- Institute of Biochemistry II, Goethe University Frankfurt, Theodor-Stern-Kai 7, Haus 75, 60590 Frankfurt am Main, Germany
| | - Süleyman Bozkurt
- Institute of Biochemistry II, Goethe University Frankfurt, Theodor-Stern-Kai 7, Haus 75, 60590 Frankfurt am Main, Germany
| | - Jonas Benjamin Michaelis
- Institute of Biochemistry II, Goethe University Frankfurt, Theodor-Stern-Kai 7, Haus 75, 60590 Frankfurt am Main, Germany
| | - Kevin Klann
- Institute of Biochemistry II, Goethe University Frankfurt, Theodor-Stern-Kai 7, Haus 75, 60590 Frankfurt am Main, Germany
| | - Christian Münch
- Institute of Biochemistry II, Goethe University Frankfurt, Theodor-Stern-Kai 7, Haus 75, 60590 Frankfurt am Main, Germany; Frankfurt Cancer Institute, Frankfurt am Main, Germany; Cardio-Pulmonary Institute, Frankfurt am Main, Germany.
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22
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Koch C, Schuldiner M, Herrmann JM. ER-SURF: Riding the Endoplasmic Reticulum Surface to Mitochondria. Int J Mol Sci 2021; 22:9655. [PMID: 34502567 PMCID: PMC8432098 DOI: 10.3390/ijms22179655] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 08/29/2021] [Indexed: 02/08/2023] Open
Abstract
Most mitochondrial proteins are synthesized in the cytosol and targeted to the mitochondrial surface in a post-translational manner. The surface of the endoplasmic reticulum (ER) plays an active role in this targeting reaction. ER-associated chaperones interact with certain mitochondrial membrane protein precursors and transfer them onto receptor proteins of the mitochondrial surface in a process termed ER-SURF. ATP-driven proteins in the membranes of mitochondria (Msp1, ATAD1) and the ER (Spf1, P5A-ATPase) serve as extractors for the removal of mislocalized proteins. If the re-routing to mitochondria fails, precursors can be degraded by ER or mitochondria-associated degradation (ERAD or MAD respectively) in a proteasome-mediated reaction. This review summarizes the current knowledge about the cooperation of the ER and mitochondria in the targeting and quality control of mitochondrial precursor proteins.
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Affiliation(s)
- Christian Koch
- Cell Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany;
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel;
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23
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Schneider K, Zimmer D, Nielsen H, Herrmann JM, Mühlhaus T. iMLP, a predictor for internal matrix targeting-like sequences in mitochondrial proteins. Biol Chem 2021; 402:937-943. [PMID: 34218542 DOI: 10.1515/hsz-2021-0185] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/07/2021] [Indexed: 12/17/2022]
Abstract
Matrix targeting sequences (MTSs) direct proteins from the cytosol into mitochondria. Efficient targeting often relies on internal matrix targeting-like sequences (iMTS-Ls) which share structural features with MTSs. Predicting iMTS-Ls was tedious and required multiple tools and webservices. We present iMLP, a deep learning approach for the prediction of iMTS-Ls in protein sequences. A recurrent neural network has been trained to predict iMTS-L propensity profiles for protein sequences of interest. The iMLP predictor considerably exceeds the speed of existing approaches. Expanding on our previous work on iMTS-L prediction, we now serve an intuitive iMLP webservice available at http://iMLP.bio.uni-kl.de and a stand-alone command line tool for power user in addition.
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Affiliation(s)
- Kevin Schneider
- Computational Systems Biology, University of Kaiserslautern, Paul-Ehrlich-Strasse 23, D-67663 Kaiserslautern, Germany
| | - David Zimmer
- Computational Systems Biology, University of Kaiserslautern, Paul-Ehrlich-Strasse 23, D-67663 Kaiserslautern, Germany
| | - Henrik Nielsen
- Department of Health Technology, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | | | - Timo Mühlhaus
- Computational Systems Biology, University of Kaiserslautern, Paul-Ehrlich-Strasse 23, D-67663 Kaiserslautern, Germany
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Laborenz J, Bykov YS, Knöringer K, Räschle M, Filker S, Prescianotto-Baschong C, Spang A, Tatsuta T, Langer T, Storchová Z, Schuldiner M, Herrmann JM. The ER protein Ema19 facilitates the degradation of nonimported mitochondrial precursor proteins. Mol Biol Cell 2021; 32:664-674. [PMID: 33596095 PMCID: PMC8108515 DOI: 10.1091/mbc.e20-11-0748] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
For the biogenesis of mitochondria, hundreds of proteins need to be targeted from the cytosol into the various compartments of this organelle. The intramitochondrial targeting routes these proteins take to reach their respective location in the organelle are well understood. However, the early targeting processes, from cytosolic ribosomes to the membrane of the organelle, are still largely unknown. In this study, we present evidence that an integral membrane protein of the endoplasmic reticulum (ER), Ema19, plays a role in this process. Mutants lacking Ema19 show an increased stability of mitochondrial precursor proteins, indicating that Ema19 promotes the proteolytic degradation of nonproductive precursors. The deletion of Ema19 improves the growth of respiration-deficient cells, suggesting that Ema19-mediated degradation can compete with productive protein import into mitochondria. Ema19 is the yeast representative of a conserved protein family. The human Ema19 homologue is known as sigma 2 receptor or TMEM97. Though its molecular function is not known, previous studies suggested a role of the sigma 2 receptor as a quality control factor in the ER, compatible with our observations about Ema19. More globally, our data provide an additional demonstration of the important role of the ER in mitochondrial protein targeting.
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Affiliation(s)
- Janina Laborenz
- Cell Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Yury S Bykov
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | | | - Markus Räschle
- Molecular Genetics, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Sabine Filker
- Molecular Ecology, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | | | - Anne Spang
- Biozentrum, University of Basel, CH-4056 Basel, Switzerland
| | - Takashi Tatsuta
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Thomas Langer
- Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Zuzana Storchová
- Molecular Genetics, University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
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Krämer L, Groh C, Herrmann JM. The proteasome: friend and foe of mitochondrial biogenesis. FEBS Lett 2020; 595:1223-1238. [PMID: 33249599 DOI: 10.1002/1873-3468.14010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/26/2020] [Accepted: 11/01/2020] [Indexed: 01/06/2023]
Abstract
Most mitochondrial proteins are synthesized in the cytosol and subsequently translocated as unfolded polypeptides into mitochondria. Cytosolic chaperones maintain precursor proteins in an import-competent state. This post-translational import reaction is under surveillance of the cytosolic ubiquitin-proteasome system, which carries out several distinguishable activities. On the one hand, the proteasome degrades nonproductive protein precursors from the cytosol and nucleus, import intermediates that are stuck in mitochondrial translocases, and misfolded or damaged proteins from the outer membrane and the intermembrane space. These surveillance activities of the proteasome are essential for mitochondrial functionality, as well as cellular fitness and survival. On the other hand, the proteasome competes with mitochondria for nonimported cytosolic precursor proteins, which can compromise mitochondrial biogenesis. In order to balance the positive and negative effects of the cytosolic protein quality control system on mitochondria, mitochondrial import efficiency directly regulates the capacity of the proteasome via transcription factor Rpn4 in yeast and nuclear respiratory factor (Nrf) 1 and 2 in animal cells. In this review, we provide a thorough overview of how the proteasome regulates mitochondrial biogenesis.
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Affiliation(s)
- Lena Krämer
- Cell Biology, University of Kaiserslautern, Germany
| | - Carina Groh
- Cell Biology, University of Kaiserslautern, Germany
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26
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Zöller E, Laborenz J, Krämer L, Boos F, Räschle M, Alexander RT, Herrmann JM. The intermembrane space protein Mix23 is a novel stress-induced mitochondrial import factor. J Biol Chem 2020; 295:14686-14697. [PMID: 32826315 PMCID: PMC7586232 DOI: 10.1074/jbc.ra120.014247] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 08/19/2020] [Indexed: 12/20/2022] Open
Abstract
The biogenesis of mitochondria requires the import of hundreds of precursor proteins. These proteins are transported post-translationally with the help of chaperones, meaning that the overproduction of mitochondrial proteins or the limited availability of chaperones can lead to the accumulation of cytosolic precursor proteins. This imposes a severe challenge to cytosolic proteostasis and triggers a specific transcription program called the mitoprotein-induced stress response, which activates the proteasome system. This coincides with the repression of mitochondrial proteins, including many proteins of the intermembrane space. In contrast, herein we report that the so-far-uncharacterized intermembrane space protein Mix23 is considerably up-regulated when mitochondrial import is perturbed. Mix23 is evolutionarily conserved and a homolog of the human protein CCDC58. We found that, like the subunits of the proteasome, Mix23 is under control of the transcription factor Rpn4. It is imported into mitochondria by the mitochondrial disulfide relay. Mix23 is critical for the efficient import of proteins into the mitochondrial matrix, particularly if the function of the translocase of the inner membrane 23 is compromised such as in temperature-sensitive mutants of Tim17. Our observations identify Mix23 as a novel regulator or stabilizer of the mitochondrial protein import machinery that is specifically up-regulated upon mitoprotein-induced stress conditions.
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Affiliation(s)
- Eva Zöller
- Department of Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Janina Laborenz
- Department of Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Lena Krämer
- Department of Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Felix Boos
- Department of Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Markus Räschle
- Department of Molecular Genetics, University of Kaiserslautern, Kaiserslautern, Germany
| | - R Todd Alexander
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Johannes M Herrmann
- Department of Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany.
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27
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Garin S, Levi O, Cohen B, Golani-Armon A, Arava YS. Localization and RNA Binding of Mitochondrial Aminoacyl tRNA Synthetases. Genes (Basel) 2020; 11:genes11101185. [PMID: 33053729 PMCID: PMC7600831 DOI: 10.3390/genes11101185] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/05/2020] [Accepted: 10/08/2020] [Indexed: 12/15/2022] Open
Abstract
Mitochondria contain a complete translation machinery that is used to translate its internally transcribed mRNAs. This machinery uses a distinct set of tRNAs that are charged with cognate amino acids inside the organelle. Interestingly, charging is executed by aminoacyl tRNA synthetases (aaRS) that are encoded by the nuclear genome, translated in the cytosol, and need to be imported into the mitochondria. Here, we review import mechanisms of these enzymes with emphasis on those that are localized to both mitochondria and cytosol. Furthermore, we describe RNA recognition features of these enzymes and their interaction with tRNA and non-tRNA molecules. The dual localization of mitochondria-destined aaRSs and their association with various RNA types impose diverse impacts on cellular physiology. Yet, the breadth and significance of these functions are not fully resolved. We highlight here possibilities for future explorations.
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28
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Bertgen L, Mühlhaus T, Herrmann JM. Clingy genes: Why were genes for ribosomal proteins retained in many mitochondrial genomes? BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148275. [PMID: 32712152 DOI: 10.1016/j.bbabio.2020.148275] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/14/2020] [Accepted: 07/19/2020] [Indexed: 11/18/2022]
Abstract
Why mitochondria still retain their own genome is a puzzle given the enormous effort to maintain a mitochondrial translation machinery. Most mitochondrially encoded proteins are membrane-embedded subunits of the respiratory chain. Their hydrophobicity presumably impedes their import into mitochondria. However, many mitochondrial genomes also encode protein subunits of the mitochondrial ribosome. These proteins lack transmembrane domains and hydrophobicity cannot explain why their genes remained in mitochondria. In this review, we provide an overview about mitochondrially encoded subunits of mitochondrial ribosomes of fungi, plants and protists. Moreover, we discuss and evaluate different hypotheses which were put forward to explain why (ribosomal) proteins remained mitochondrially encoded. It seems likely that the synthesis of ribosomal proteins in the mitochondrial matrix is used to regulate the assembly of the mitochondrial ribosome within mitochondria and to avoid problems that mitochondrial proteins might pose for cytosolic proteostasis and for the assembly of cytosolic ribosomes.
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Affiliation(s)
- Lea Bertgen
- Cell Biology, University of Kaiserslautern, Erwin-Schrödinger-Straße 13, 67663 Kaiserslautern, Germany
| | - Timo Mühlhaus
- Computational Systems Biology, University of Kaiserslautern, Erwin-Schrödinger-Straße 23, 67663 Kaiserslautern, Germany
| | - Johannes M Herrmann
- Cell Biology, University of Kaiserslautern, Erwin-Schrödinger-Straße 13, 67663 Kaiserslautern, Germany.
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Horten P, Colina-Tenorio L, Rampelt H. Biogenesis of Mitochondrial Metabolite Carriers. Biomolecules 2020; 10:E1008. [PMID: 32645990 PMCID: PMC7408425 DOI: 10.3390/biom10071008] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/02/2020] [Accepted: 07/03/2020] [Indexed: 12/28/2022] Open
Abstract
: Metabolite carriers of the mitochondrial inner membrane are crucial for cellular physiology since mitochondria contribute essential metabolic reactions and synthesize the majority of the cellular ATP. Like almost all mitochondrial proteins, carriers have to be imported into mitochondria from the cytosol. Carrier precursors utilize a specialized translocation pathway dedicated to the biogenesis of carriers and related proteins, the carrier translocase of the inner membrane (TIM22) pathway. After recognition and import through the mitochondrial outer membrane via the translocase of the outer membrane (TOM) complex, carrier precursors are ushered through the intermembrane space by hexameric TIM chaperones and ultimately integrated into the inner membrane by the TIM22 carrier translocase. Recent advances have shed light on the mechanisms of TOM translocase and TIM chaperone function, uncovered an unexpected versatility of the machineries, and revealed novel components and functional crosstalk of the human TIM22 translocase.
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Affiliation(s)
- Patrick Horten
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; (P.H.); (L.C.-T.)
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Lilia Colina-Tenorio
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; (P.H.); (L.C.-T.)
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Heike Rampelt
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; (P.H.); (L.C.-T.)
- CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
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