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Özdemir M, Dennerlein S. The TOM complex from an evolutionary perspective and the functions of TOMM70. Biol Chem 2024; 0:hsz-2024-0043. [PMID: 39092472 DOI: 10.1515/hsz-2024-0043] [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: 03/15/2024] [Accepted: 07/17/2024] [Indexed: 08/04/2024]
Abstract
In humans, up to 1,500 mitochondrial precursor proteins are synthesized at cytosolic ribosomes and must be imported into the organelle. This is not only essential for mitochondrial but also for many cytosolic functions. The majority of mitochondrial precursor proteins are imported over the translocase of the outer membrane (TOM). In recent years, high-resolution structure analyses from different organisms shed light on the composition and arrangement of the TOM complex. Although significant similarities have been found, differences were also observed, which have been favored during evolution and could reflect the manifold functions of TOM with cellular signaling and its response to altered metabolic situations. A key component within these regulatory mechanisms is TOMM70, which is involved in protein import, forms contacts to the ER and the nucleus, but is also involved in cellular defense mechanisms during infections.
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Affiliation(s)
- Metin Özdemir
- Institute for Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Sven Dennerlein
- Institute for Cellular Biochemistry, University Medical Center Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
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2
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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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3
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Su J, Tian X, Wang Z, Yang J, Sun S, Sui SF. Structure of the intact Tom20 receptor in the human translocase of the outer membrane complex. PNAS NEXUS 2024; 3:pgae269. [PMID: 39071881 PMCID: PMC11273160 DOI: 10.1093/pnasnexus/pgae269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 06/21/2024] [Indexed: 07/30/2024]
Abstract
The translocase of the outer membrane (TOM) complex serves as the main gate for preproteins entering mitochondria and thus plays a pivotal role in sustaining mitochondrial stability. Precursor proteins, featuring amino-terminal targeting signals (presequences) or internal targeting signals, are recognized by the TOM complex receptors Tom20, Tom22, and Tom70, and then translocated into mitochondria through Tom40. By using chemical cross-linking to stabilize Tom20 in the TOM complex, this study unveils the structure of the human TOM holo complex, encompassing the intact Tom20 component, at a resolution of approximately 6 Å by cryo-electron microscopy. Our structure shows the TOM holo complex containing only one Tom20 subunit, which is located right at the center of the complex and stabilized by extensive interactions with Tom22, Tom40, and Tom6. Based on the structure, we proposed a possible translocation mode of TOM complex, by which different receptors could work simultaneously to ensure that the preproteins recognized by them are all efficiently translocated into the mitochondria.
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Affiliation(s)
- Jiayue Su
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xuyang Tian
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ziyi Wang
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jiawen Yang
- School of Life Sciences, Cryo-EM Center, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
| | - Shan Sun
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Sen-Fang Sui
- State Key Laboratory of Membrane Biology, Beijing Frontier Research Center for Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- School of Life Sciences, Cryo-EM Center, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
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Ku D, Yang Y, Park Y, Jang D, Lee N, Lee YK, Lee K, Lee J, Han YB, Jang S, Choi SR, Ha YJ, Choi YS, Jeong WJ, Lee YJ, Lee KJ, Cha S, Kim Y. SLIRP promotes autoimmune diseases by amplifying antiviral signaling via positive feedback regulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.28.587146. [PMID: 38915695 PMCID: PMC11195051 DOI: 10.1101/2024.03.28.587146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
The abnormal innate immune response is a prominent feature underlying autoimmune diseases. One emerging factor that can trigger dysregulated immune activation is cytosolic mitochondrial double-stranded RNAs (mt-dsRNAs). However, the mechanism by which mt-dsRNAs stimulate immune responses remains poorly understood. Here, we discover SRA stem-loop interacting RNA binding protein (SLIRP) as a key amplifier of mt-dsRNA-triggered antiviral signals. In autoimmune diseases, SLIRP is commonly upregulated, and targeted knockdown of SLIRP dampens the interferon response. We find that the activation of melanoma differentiation-associated gene 5 (MDA5) by exogenous dsRNAs upregulates SLIRP, which then stabilizes mt-dsRNAs and promotes their cytosolic release to activate MDA5 further, augmenting the interferon response. Furthermore, the downregulation of SLIRP partially rescues the abnormal interferon-stimulated gene expression in autoimmune patients' primary cells and makes cells vulnerable to certain viral infections. Our study unveils SLIRP as a pivotal mediator of interferon response through positive feedback amplification of antiviral signaling.
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Affiliation(s)
- Doyeong Ku
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Yewon Yang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Youngran Park
- Center for RNA Research, Institute of Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Daesong Jang
- Department of Oral and Maxillofacial Diagnostic Science, Center for Orphaned Autoimmune Disorders, University of Florida College of Dentistry, Gainesville, Florida, 32610, United States of America
| | - Namseok Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Yong-ki Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Keonyong Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jaeseon Lee
- R&D Institute, ORGANOIDSCIENCES Ltd., Seongnam, 13488, Republic of Korea
| | - Yeon Bi Han
- Department of Pathology and Translational Medicine, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Soojin Jang
- R&D Institute, ORGANOIDSCIENCES Ltd., Seongnam, 13488, Republic of Korea
| | - Se Rim Choi
- Division of Rheumatology, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - You-Jung Ha
- Division of Rheumatology, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Yong Seok Choi
- Medical Science Research Institute, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Woo-Jin Jeong
- Department of Otorhinolaryngology - Head & Neck Surgery, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
- Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Yun Jong Lee
- Department of Pathology and Translational Medicine, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
- Division of Rheumatology, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, 13620, Republic of Korea
| | - Kyung Jin Lee
- R&D Institute, ORGANOIDSCIENCES Ltd., Seongnam, 13488, Republic of Korea
| | - Seunghee Cha
- Department of Oral and Maxillofacial Diagnostic Science, Center for Orphaned Autoimmune Disorders, University of Florida College of Dentistry, Gainesville, Florida, 32610, United States of America
| | - Yoosik Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Graduate School of Engineering Biology, KAIST, Daejeon, 34141, Republic of Korea
- KAIST Institute for BioCentury (KIB), Daejeon, 34141, Republic of Korea
- KAIST Institute for Health Science and Technology (KIHST), Daejeon 34141, Republic of Korea
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Li Z, Bao Z, Tan J, Chen G, Ye B, Zhao J, Zhang L, Xu H. Neobractatin induces pyroptosis of esophageal cancer cells by TOM20/BAX signaling pathway. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 128:155547. [PMID: 38547615 DOI: 10.1016/j.phymed.2024.155547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 01/29/2024] [Accepted: 03/17/2024] [Indexed: 05/01/2024]
Abstract
BACKGROUND Emerging evidence suggests that pyroptosis, a form of programmed cell death, has been implicated in cancer progression. The involvement of specific proteins in pyroptosis is an area of growing interest. TOM20, an outer mitochondrial membrane protein, has recently garnered attention for its potential role in pyroptosis. Our previous study found that NBT could induce pyroptosis by ROS/JNK pathway in esophageal cancer cells. PURPOSE This study aims to investigate whether NBT induces pyroptosis and verify whether such effects are involved in up-regulation of TOM20 in esophageal cancer cells. METHODS The University of ALabama at Birmingham CANcer data analysis Portal (UALCAN) was used to analyze the clinical significance of GSDME in esophageal cancer. MTT assay, morphological observation and Western blot were performed to verify the roles of TOM20 and BAX in NBT-induced pyroptosis after CRISPR-Cas9-mediated knockout. Immunofluorescence was used to determine the subcellular locations of BAX and cytochrome c. MitoSOX Red was employed to assess the mitochondrial reactive oxygen species (ROS) level. KYSE450 and TOM20 knockout KYSE450-/- xenograft models were established to elucidate the mechanisms involved in NBT-induced cell death. RESULTS In this study, NBT effectively upregulated the expression of TOM20 and facilitated the translocation of BAX to mitochondria, which promoted the release of cytochrome c from mitochondria to the cytoplasm, leading to the activation of caspase-9 and caspase-3, and finally induced pyroptosis. Knocking out TOM20 by CRISPR-Cas9 significantly inhibited the expression of BAX and the downstream BAX/caspase-3/GSDME pathway, which attenuated NBT-induced pyroptosis. The elevated mitochondrial ROS level was observed after NBT treatment. Remarkably, the inhibition of ROS by N-acetylcysteine (NAC) effectively suppressed the activation of TOM20/BAX pathway. Moreover, in vivo experiments demonstrated that NBT exhibited potent antitumor effects in both KYSE450 and TOM20 knockout KYSE450-/- xenograft models. Notably, the attenuated antitumor effects and reduced cleavage of GSDME were observed in the TOM20 knockout model. CONCLUSION These findings reveal that NBT induces pyroptosis through ROS/TOM20/BAX/GSDME pathway, which highlight the therapeutic potential of targeting TOM20 and GSDME, providing promising prospects for the development of innovative and effective treatment approaches for esophageal cancer.
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Affiliation(s)
- Zhuo Li
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China; Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery, Shanghai, 201203, China
| | - Ziyi Bao
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China; Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery, Shanghai, 201203, China
| | - Jiaqi Tan
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China; Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery, Shanghai, 201203, China
| | - Gan Chen
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China; Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery, Shanghai, 201203, China
| | - Bingying Ye
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Juan Zhao
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Li Zhang
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China; Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery, Shanghai, 201203, China.
| | - Hongxi Xu
- Shuguang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
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Nussberger S, Ghosh R, Wang S. New insights into the structure and dynamics of the TOM complex in mitochondria. Biochem Soc Trans 2024; 52:911-922. [PMID: 38629718 PMCID: PMC11088910 DOI: 10.1042/bst20231236] [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: 02/13/2024] [Revised: 03/21/2024] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
To date, there is no general physical model of the mechanism by which unfolded polypeptide chains with different properties are imported into the mitochondria. At the molecular level, it is still unclear how transit polypeptides approach, are captured by the protein translocation machinery in the outer mitochondrial membrane, and how they subsequently cross the entropic barrier of a protein translocation pore to enter the intermembrane space. This deficiency has been due to the lack of detailed structural and dynamic information about the membrane pores. In this review, we focus on the recently determined sub-nanometer cryo-EM structures and our current knowledge of the dynamics of the mitochondrial two-pore outer membrane protein translocation machinery (TOM core complex), which provide a starting point for addressing the above questions. Of particular interest are recent discoveries showing that the TOM core complex can act as a mechanosensor, where the pores close as a result of interaction with membrane-proximal structures. We highlight unusual and new correlations between the structural elements of the TOM complexes and their dynamic behavior in the membrane environment.
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Affiliation(s)
- Stephan Nussberger
- Department of Biophysics, Institute of Biomaterials and Biomolecular Systems, University of Stuttgart, Stuttgart, Germany
| | - Robin Ghosh
- Department of Bioenergetics, Institute of Biomaterials and Biomolecular Systems, University of Stuttgart, Stuttgart, Germany
| | - Shuo Wang
- Department of Biophysics, Institute of Biomaterials and Biomolecular Systems, University of Stuttgart, Stuttgart, Germany
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Wu S, Zhang Y, Xu L, Zhang H, Li Y, Yang L, Zhang Z, Zhang H. Mitochondrial Outer Membrane Translocase MoTom20 Modulates Mitochondrial Morphology and Is Important for Infectious Growth of the Rice Blast Fungus Magnaporthe oryzae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024; 37:407-415. [PMID: 38171376 DOI: 10.1094/mpmi-10-23-0168-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Mitochondria are highly dynamic organelles that constantly change their morphology to adapt to the cellular environment through fission and fusion, which is critical for a cell to maintain normal cellular functions. Despite the significance of this process in the development and pathogenicity of the rice blast fungus Magnaporthe oryzae, the underlying mechanism remains largely elusive. Here, we identified and characterized a mitochondrial outer membrane translocase, MoTom20, in M. oryzae. Targeted gene deletion revealed that MoTom20 plays an important role in vegetative growth, conidiogenesis, penetration, and infectious growth of M. oryzae. The growth rate, conidial production, appressorium turgor, and pathogenicity are decreased in the ΔMotom20 mutant compared with the wild-type and complemented strains. Further analysis revealed that MoTom20 localizes in mitochondrion and plays a key role in regulating mitochondrial fission and fusion balance, which is critical for infectious growth. Finally, we found that MoTom20 is involved in fatty-acid utilization, and its yeast homolog ScTom20 is able to rescue the defects of ΔMotom20 in mitochondrial morphology and pathogenicity. Overall, our data demonstrate that MoTom20 is a key regulator for mitochondrial morphology maintenance, which is important for infectious growth of the rice blast fungus M. oryzae. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Shuang Wu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Ying Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Lele Xu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Haibo Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Yuhe Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Leiyun Yang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Haifeng Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
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8
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Busto JV, Ganesan I, Mathar H, Steiert C, Schneider EF, Straub SP, Ellenrieder L, Song J, Stiller SB, Lübbert P, Chatterjee R, Elsaesser J, Melchionda L, Schug C, den Brave F, Schulte U, Klecker T, Kraft C, Fakler B, Becker T, Wiedemann N. Role of the small protein Mco6 in the mitochondrial sorting and assembly machinery. Cell Rep 2024; 43:113805. [PMID: 38377000 DOI: 10.1016/j.celrep.2024.113805] [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: 08/24/2023] [Revised: 12/22/2023] [Accepted: 01/31/2024] [Indexed: 02/22/2024] Open
Abstract
The majority of mitochondrial precursor proteins are imported through the Tom40 β-barrel channel of the translocase of the outer membrane (TOM). The sorting and assembly machinery (SAM) is essential for β-barrel membrane protein insertion into the outer membrane and thus required for the assembly of the TOM complex. Here, we demonstrate that the α-helical outer membrane protein Mco6 co-assembles with the mitochondrial distribution and morphology protein Mdm10 as part of the SAM machinery. MCO6 and MDM10 display a negative genetic interaction, and a mco6-mdm10 yeast double mutant displays reduced levels of the TOM complex. Cells lacking Mco6 affect the levels of Mdm10 and show assembly defects of the TOM complex. Thus, this work uncovers a role of the SAMMco6 complex for the biogenesis of the mitochondrial outer membrane.
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Affiliation(s)
- Jon V Busto
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Iniyan Ganesan
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Hannah Mathar
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Conny Steiert
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Eva F Schneider
- 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
| | - Lars Ellenrieder
- 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
| | - Sebastian B Stiller
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Philipp Lübbert
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ritwika Chatterjee
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Jana Elsaesser
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Laura Melchionda
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christina Schug
- Institute of Cell Biology, University of Bayreuth, Bayreuth, Germany
| | - Fabian den Brave
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, Germany
| | - 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
| | - Till Klecker
- Institute of Cell Biology, University of Bayreuth, Bayreuth, Germany
| | - Claudine Kraft
- Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, Freiburg, Germany; CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - 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; BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, Bonn, 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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9
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Wang G, Cui Z, Tian J, Li X, Tang W, Jing W, Li A, Zhang Y. Paucatalinone A from Paulownia Catalpifolia Gong Tong Elicits mitochondrial-mediated cancer cell death to combat osteosarcoma. Front Pharmacol 2024; 15:1367316. [PMID: 38590635 PMCID: PMC10999585 DOI: 10.3389/fphar.2024.1367316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/11/2024] [Indexed: 04/10/2024] Open
Abstract
As the global cancer burden escalates, the search for alternative therapies becomes increasingly vital. Natural products, particularly plant-derived compounds, have emerged as promising alternatives to conventional cancer treatments due to their diverse bioactivities and favorable biosafety profiles. Here, we investigate Paucatalinone A, a newly discovered geranylated flavanone derived from the fruit of Paulownia Catalpifolia Gong Tong, notable for its significant anti-cancer properties. We revealed the capability of Paucatalinone A to induce apoptosis in osteosarcoma cells and deciphered its underlying mechanisms. Our findings demonstrate that Paucatalinone A substantially augments apoptosis, inhibits cell proliferation, and demonstrates a pronounced anti-tumor effect in a murine model of osteosarcoma. Mechanistically, Paucatalinone A disrupts calcium homeostasis and exacerbates intracellular reactive oxygen species accumulation, leading to mitochondrial impairment, cytoskeletal collapse, and caspase-dependent apoptotic cell death. This study underscores the potential of Paucatalinone A in initiating apoptosis in cancer cells and highlights the therapeutic efficacy of plant-derived agents in treating osteosarcoma, offering a viable approach for managing other intractable cancers.
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Affiliation(s)
- Ganyu Wang
- Department of Pediatric Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Zhiwei Cui
- Department of Orthopedics, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Jinqiu Tian
- Department of Pediatric Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Xinyuan Li
- Department of Immunology, Shandong Provincial Key Laboratory of Infection Immunology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Wenzhao Tang
- School of Parmacy and Pharmaceutical Sciences, Institute of Materia Medica, Shandong First Medical University, Shandong Academy of Medical Sciences, NHC Key Laboratory of Biotechnology Drugs (Shandong Academy of Medical Sciences), Key Lab for Rare Uncommon Diseases of Shandong Province, Jinan, China
| | - Weiqiang Jing
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Aiwu Li
- Department of Pediatric Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Yuankai Zhang
- Department of Orthopedics, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
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10
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Muthukumar G, Stevens TA, Inglis AJ, Esantsi TK, Saunders RA, Schulte F, Voorhees RM, Guna A, Weissman JS. Triaging of α-helical proteins to the mitochondrial outer membrane by distinct chaperone machinery based on substrate topology. Mol Cell 2024; 84:1101-1119.e9. [PMID: 38428433 DOI: 10.1016/j.molcel.2024.01.028] [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: 07/31/2023] [Revised: 12/08/2023] [Accepted: 01/31/2024] [Indexed: 03/03/2024]
Abstract
Mitochondrial outer membrane ⍺-helical proteins play critical roles in mitochondrial-cytoplasmic communication, but the rules governing the targeting and insertion of these biophysically diverse proteins remain unknown. Here, we first defined the complement of required mammalian biogenesis machinery through genome-wide CRISPRi screens using topologically distinct membrane proteins. Systematic analysis of nine identified factors across 21 diverse ⍺-helical substrates reveals that these components are organized into distinct targeting pathways that act on substrates based on their topology. NAC is required for the efficient targeting of polytopic proteins, whereas signal-anchored proteins require TTC1, a cytosolic chaperone that physically engages substrates. Biochemical and mutational studies reveal that TTC1 employs a conserved TPR domain and a hydrophobic groove in its C-terminal domain to support substrate solubilization and insertion into mitochondria. Thus, the targeting of diverse mitochondrial membrane proteins is achieved through topological triaging in the cytosol using principles with similarities to ER membrane protein biogenesis systems.
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Affiliation(s)
- Gayathri Muthukumar
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Taylor A Stevens
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Alison J Inglis
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Theodore K Esantsi
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Reuben A Saunders
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Fabian Schulte
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Rebecca M Voorhees
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Alina Guna
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA.
| | - Jonathan S Weissman
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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11
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Wen-Jing Z, Rui-Zhi T, Si-Yuan H, Xiao-Mei D, Qiong-Dan H, Xiao-Qian Z, Wen-Hua H, Hong-Wei S, Jian L, Qiong Z, Li W. Data independent acquisition reveals in-depth serum proteome changes in uremic pruritus. Front Physiol 2024; 15:1287072. [PMID: 38577622 PMCID: PMC10991838 DOI: 10.3389/fphys.2024.1287072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 02/29/2024] [Indexed: 04/06/2024] Open
Abstract
Introduction: Uremic pruritus (UP) is a prevalent symptom in patients suffering from uremia, yet its underlying etiology and mechanisms remain incompletely elucidated. Given the significant incidence of UP, identifying specific alterations in proteins present in the blood of UP patients could offer insights into the potential biological pathways associated with UP and facilitate the exploration of biomarkers. Methods: In this study, we employed LC-MS/MS-based data-independent acquisition (DIA) mode to analyze serum samples obtained from 54 UP patients categorized as DKD-UP, HN-UP, and GN-UP (n = 18 for each subgroup), along with 18 uremic patients without pruritus (Negative) and 18 CKD patients without pruritus (CKD). Through DIA mode analysis, a total of 7075 peptides and 959 proteins were quantified. Within these, we identified four upregulated and 13 downregulated Differentially Expressed Proteins (DEPs) in DKD-UP versus Negative, five upregulated and 22 downregulated DEPs in HN-UP versus Negative, and three upregulated and 23 downregulated DEPs in GN-UP versus Negative. Furthermore, we conducted an intersection analysis of the DEPs across these three comparison groups to derive a set of common DEPs (COMP). Subsequently, a total of 67 common DEPs were identified in the three UP groups when compared to the CKD group, with 40 DEPs showing upregulation and 27 DEPs displaying downregulation. Results: Following Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI) analyses, we observed that the DEPs distinguishing UP from CKD were primarily associated with mitochondrial function (MT-CYB, PRDX2, TOMM22), inflammation (CD59, CSF1), renal injury (WFDC2), and neural function (CAP1, VGF). Discussion: Our findings contribute to a potential molecular comprehension of UP pathogenesis, shedding light on the identification of these DEPs as plausible biomarkers for UP.
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Affiliation(s)
- Zhao Wen-Jing
- Research Center of Intergated Traditional Chinese and Western Medicine, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
- Department of Nephrology, The Affiliated Hospital, Southwest Medical University, Luzhou, China
| | - Tan Rui-Zhi
- Research Center of Intergated Traditional Chinese and Western Medicine, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - He Si-Yuan
- School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Du Xiao-Mei
- Department of Nephrology, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - Hu Qiong-Dan
- Research Center of Intergated Traditional Chinese and Western Medicine, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
- Department of Nephrology, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - Zhang Xiao-Qian
- Research Center of Intergated Traditional Chinese and Western Medicine, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
- Department of Nephrology, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - Huang Wen-Hua
- School of Clinical Medicine, Southern Medical University, Guangzhou, China
| | - Su Hong-Wei
- Department of Urology, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - Liu Jian
- Department of Nephrology, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - Zhang Qiong
- Department of Nephrology, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
| | - Wang Li
- Research Center of Intergated Traditional Chinese and Western Medicine, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, China
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12
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Eldeeb MA, Bayne AN, Fallahi A, Goiran T, MacDougall EJ, Soumbasis A, Zorca CE, Tabah JJ, Thomas RA, Karpilovsky N, Mathur M, Durcan TM, Trempe JF, Fon EA. Tom20 gates PINK1 activity and mediates its tethering of the TOM and TIM23 translocases upon mitochondrial stress. Proc Natl Acad Sci U S A 2024; 121:e2313540121. [PMID: 38416681 DOI: 10.1073/pnas.2313540121] [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: 08/13/2023] [Accepted: 01/08/2024] [Indexed: 03/01/2024] Open
Abstract
Mutations in PTEN-induced putative kinase 1 (PINK1) cause autosomal recessive early-onset Parkinson's disease (PD). PINK1 is a Ser/Thr kinase that regulates mitochondrial quality control by triggering mitophagy mediated by the ubiquitin (Ub) ligase Parkin. Upon mitochondrial damage, PINK1 accumulates on the outer mitochondrial membrane forming a high-molecular-weight complex with the translocase of the outer membrane (TOM). PINK1 then phosphorylates Ub, which enables recruitment and activation of Parkin followed by autophagic clearance of the damaged mitochondrion. Thus, Parkin-dependent mitophagy hinges on the stable accumulation of PINK1 on the TOM complex. Yet, the mechanism linking mitochondrial stressors to PINK1 accumulation and whether the translocases of the inner membrane (TIMs) are also involved remain unclear. Herein, we demonstrate that mitochondrial stress induces the formation of a PINK1-TOM-TIM23 supercomplex in human cultured cell lines, dopamine neurons, and midbrain organoids. Moreover, we show that PINK1 is required to stably tether the TOM to TIM23 complexes in response to stress such that the supercomplex fails to accumulate in cells lacking PINK1. This tethering is dependent on an interaction between the PINK1 N-terminal-C-terminal extension module and the cytosolic domain of the Tom20 subunit of the TOM complex, the disruption of which, by either designer or PD-associated PINK1 mutations, inhibits downstream mitophagy. Together, the findings provide key insight into how PINK1 interfaces with the mitochondrial import machinery, with important implications for the mechanisms of mitochondrial quality control and PD pathogenesis.
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Affiliation(s)
- Mohamed A Eldeeb
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Andrew N Bayne
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada
- Centre de Recherche en Biologie Structurale, Montréal, QC H3G 0B1, Canada
| | - Armaan Fallahi
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Thomas Goiran
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Emma J MacDougall
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Andrea Soumbasis
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Cornelia E Zorca
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Jace-Jones Tabah
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Rhalena A Thomas
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Nathan Karpilovsky
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Meghna Mathur
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Thomas M Durcan
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
| | - Jean-François Trempe
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC H3G 1Y6, Canada
- Centre de Recherche en Biologie Structurale, Montréal, QC H3G 0B1, Canada
| | - Edward A Fon
- McGill Parkinson Program and Neurodegenerative Disorders Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montréal, QC H3A 2B4, Canada
- Structural Genomics Consortium - Neuro, McGill University, Montréal, QC H3A 2B4, Canada
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13
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den Brave F, Pfanner N, Becker T. Mitochondrial entry gate as regulatory hub. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119529. [PMID: 37951505 DOI: 10.1016/j.bbamcr.2023.119529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 06/18/2023] [Accepted: 06/23/2023] [Indexed: 11/14/2023]
Abstract
Mitochondria import 1000-1300 different precursor proteins from the cytosol. The main mitochondrial entry gate is formed by the translocase of the outer membrane (TOM complex). Molecular coupling and modification of TOM subunits control and modulate protein import in response to cellular signaling. The TOM complex functions as regulatory hub to integrate mitochondrial protein biogenesis and quality control into the cellular proteostasis network.
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Affiliation(s)
- Fabian den Brave
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, 53115 Bonn, 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.
| | - Thomas Becker
- Institute of Biochemistry and Molecular Biology, Faculty of Medicine, University of Bonn, 53115 Bonn, Germany.
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14
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Ronayne CT, Latorre-Muro P. Navigating the landscape of mitochondrial-ER communication in health and disease. Front Mol Biosci 2024; 11:1356500. [PMID: 38323074 PMCID: PMC10844478 DOI: 10.3389/fmolb.2024.1356500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 01/10/2024] [Indexed: 02/08/2024] Open
Abstract
Intracellular organelle communication enables the maintenance of tissue homeostasis and health through synchronized adaptive processes triggered by environmental cues. Mitochondrial-Endoplasmic Reticulum (ER) communication sustains cellular fitness by adjusting protein synthesis and degradation, and metabolite and protein trafficking through organelle membranes. Mitochondrial-ER communication is bidirectional and requires that the ER-components of the Integrated Stress Response signal to mitochondria upon activation and, likewise, mitochondria signal to the ER under conditions of metabolite and protein overload to maintain proper functionality and ensure cellular survival. Declines in the mitochondrial-ER communication occur upon ageing and correlate with the onset of a myriad of heterogeneous age-related diseases such as obesity, type 2 diabetes, cancer, or neurodegenerative pathologies. Thus, the exploration of the molecular mechanisms of mitochondrial-ER signaling and regulation will provide insights into the most fundamental cellular adaptive processes with important therapeutical opportunities. In this review, we will discuss the pathways and mechanisms of mitochondrial-ER communication at the mitochondrial-ER interface and their implications in health and disease.
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Affiliation(s)
- Conor T. Ronayne
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, United States
- Department of Cell Biology, Harvard Medical School, Boston, MA, United States
| | - Pedro Latorre-Muro
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, United States
- Department of Cell Biology, Harvard Medical School, Boston, MA, United States
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15
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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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16
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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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17
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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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18
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Tang J, Lu X, Zhang T, Feng Y, Xu Q, Li J, Lan Y, Luo H, Zeng L, Xiang Y, Zhang Y, Li Q, Mao X, Tang B, Zeng D. Shiga toxin 2 A-subunit induces mitochondrial damage, mitophagy and apoptosis via the interaction of Tom20 in Caco-2 cells. Heliyon 2023; 9:e20012. [PMID: 37809632 PMCID: PMC10559750 DOI: 10.1016/j.heliyon.2023.e20012] [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: 03/23/2023] [Revised: 08/18/2023] [Accepted: 09/08/2023] [Indexed: 10/10/2023] Open
Abstract
Shiga toxin type 2 (Stx2) is the primary virulence factor produced by Shiga toxin-producing enterohemorrhagic Escherichia coli (STEC), which causes epidemic outbreaks of gastrointestinal sickness and potentially fatal sequela hemolytic uremic syndrome (HUS). Most studies on Stx2-induced apoptosis have been performed with holotoxins, but the mechanism of how the A and B subunits of Stx2 cause apoptosis in cells is not clear. Here, we found that Stx2 A-subunit (Stx2A) induced mitochondrial damage, PINK1/Parkin-dependent mitophagy and apoptosis in Caco-2 cells. PINK1/Parkin-dependent mitophagy caused by Stx2A reduced apoptosis by decreasing the accumulation of reactive oxidative species (ROS). Mechanistically, Stx2A interacts with Tom20 on mitochondria to initiate the translocation of Bax to mitochondria, leading to mitochondrial damage and apoptosis. Overall, these data suggested that Stx2A induces mitochondrial damage, mitophagy and apoptosis via the interaction of Tom20 in Caco-2 cells and that mitophagy caused by Stx2A ameliorates apoptosis by eliminating damaged mitochondria. These findings provide evidence for the potential use of Tom20 inhibition as an anti-Shiga toxin therapy.
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Affiliation(s)
- Jie Tang
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Xiaoxue Lu
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Medical Laboratory, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Tao Zhang
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Yuyang Feng
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Medical Laboratory, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Qiaolin Xu
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Jing Li
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Yuanzhi Lan
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Huaxing Luo
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Linghai Zeng
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Yuanyuan Xiang
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Yan Zhang
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
| | - Qian Li
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Medical Laboratory, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Xuhu Mao
- Department of Clinical Microbiology and Immunology, College of Pharmacy and Medical Laboratory, Army Medical University (Third Military Medical University), Chongqing, 400038, China
| | - Bin Tang
- Department of Clinical Laboratory, Chongqing University Jiangjin Hospital, School of Medicine, Chongqing University, Jiangjin, Chongqing, 402260, China
| | - Dongzhu Zeng
- Department of General Surgery, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, China
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19
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Ornelas P, Bausewein T, Martin J, Morgner N, Nussberger S, Kühlbrandt W. Two conformations of the Tom20 preprotein receptor in the TOM holo complex. Proc Natl Acad Sci U S A 2023; 120:e2301447120. [PMID: 37579144 PMCID: PMC10450662 DOI: 10.1073/pnas.2301447120] [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: 01/30/2023] [Accepted: 07/17/2023] [Indexed: 08/16/2023] Open
Abstract
The TOM complex is the main entry point for precursor proteins (preproteins) into mitochondria. Preproteins containing targeting sequences are recognized by the TOM complex and imported into mitochondria. We have determined the structure of the TOM core complex from Neurospora crassa by single-particle electron cryomicroscopy at 3.3 Å resolution, showing its interaction with a bound preprotein at 4 Å resolution, and of the TOM holo complex including the Tom20 receptor at 6 to 7 Å resolution. TOM is a transmembrane complex consisting of two β-barrels, three receptor subunits, and three short transmembrane subunits. Tom20 has a transmembrane helix and a receptor domain on the cytoplasmic side. We propose that Tom20 acts as a dynamic gatekeeper, guiding preproteins into the pores of the TOM complex. We analyze the interactions of Tom20 with other TOM subunits, present insights into the structure of the TOM holo complex, and suggest a translocation mechanism.
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Affiliation(s)
- Pamela Ornelas
- Department of Structural Biology, Max-Planck-Institute of Biophysics, Frankfurt60438, Germany
| | - Thomas Bausewein
- Department of Structural Biology, Max-Planck-Institute of Biophysics, Frankfurt60438, Germany
| | - Janosch Martin
- Department of Structural Biology, Institute of Physical and Theoretical Chemistry, Goethe University of Frankfurt, Frankfurt60439, Germany
| | - Nina Morgner
- Department of Structural Biology, Institute of Physical and Theoretical Chemistry, Goethe University of Frankfurt, Frankfurt60439, Germany
| | - Stephan Nussberger
- Department of Biophysics, Institute of Biomaterials and Biomolecular Systems, University of Stuttgart, Stuttgart70569, Germany
| | - Werner Kühlbrandt
- Department of Structural Biology, Max-Planck-Institute of Biophysics, Frankfurt60438, Germany
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20
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Muthukumar G, Stevens TA, Inglis AJ, Esantsi TK, Saunders RA, Schulte F, Voorhees RM, Guna A, Weissman JS. Triaging of α-helical proteins to the mitochondrial outer membrane by distinct chaperone machinery based on substrate topology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.16.553624. [PMID: 37645817 PMCID: PMC10462106 DOI: 10.1101/2023.08.16.553624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Mitochondrial outer membrane α-helical proteins play critical roles in mitochondrial-cytoplasmic communication, but the rules governing the targeting and insertion of these biophysically diverse substrates remain unknown. Here, we first defined the complement of required mammalian biogenesis machinery through genome-wide CRISPRi screens using topologically distinct membrane proteins. Systematic analysis of nine identified factors across 21 diverse α-helical substrates reveals that these components are organized into distinct targeting pathways which act on substrates based on their topology. NAC is required for efficient targeting of polytopic proteins whereas signal-anchored proteins require TTC1, a novel cytosolic chaperone which physically engages substrates. Biochemical and mutational studies reveal that TTC1 employs a conserved TPR domain and a hydrophobic groove in its C-terminal domain to support substrate solubilization and insertion into mitochondria. Thus, targeting of diverse mitochondrial membrane proteins is achieved through topological triaging in the cytosol using principles with similarities to ER membrane protein biogenesis systems.
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Affiliation(s)
- Gayathri Muthukumar
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Taylor A. Stevens
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Alison J. Inglis
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Theodore K. Esantsi
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Reuben A. Saunders
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA, USA
- Tetrad Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Fabian Schulte
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Rebecca M. Voorhees
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Alina Guna
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Avenue, Pasadena, CA 91125, USA
| | - Jonathan S. Weissman
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA, USA
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute Technology, Cambridge 02142, MA
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21
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Mayse LA, Movileanu L. Gating of β-Barrel Protein Pores, Porins, and Channels: An Old Problem with New Facets. Int J Mol Sci 2023; 24:12095. [PMID: 37569469 PMCID: PMC10418385 DOI: 10.3390/ijms241512095] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/23/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
β barrels are ubiquitous proteins in the outer membranes of mitochondria, chloroplasts, and Gram-negative bacteria. These transmembrane proteins (TMPs) execute a wide variety of tasks. For example, they can serve as transporters, receptors, membrane-bound enzymes, as well as adhesion, structural, and signaling elements. In addition, multimeric β barrels are common structural scaffolds among many pore-forming toxins. Significant progress has been made in understanding the functional, structural, biochemical, and biophysical features of these robust and versatile proteins. One frequently encountered fundamental trait of all β barrels is their voltage-dependent gating. This process consists of reversible or permanent conformational transitions between a large-conductance, highly permeable open state and a low-conductance, solute-restrictive closed state. Several intrinsic molecular mechanisms and environmental factors modulate this universal property of β barrels. This review article outlines the typical signatures of voltage-dependent gating. Moreover, we discuss recent developments leading to a better qualitative understanding of the closure dynamics of these TMPs.
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Affiliation(s)
- Lauren A. Mayse
- Department of Physics, Syracuse University, 201 Physics Building, Syracuse, NY 13244, USA;
- Department of Biomedical and Chemical Engineering, Syracuse University, 223 Link Hall, Syracuse, NY 13244, USA
| | - Liviu Movileanu
- Department of Physics, Syracuse University, 201 Physics Building, Syracuse, NY 13244, USA;
- Department of Biomedical and Chemical Engineering, Syracuse University, 223 Link Hall, Syracuse, NY 13244, USA
- The BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
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22
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Wang J, Chen S, Zhao X, Guo Q, Yang R, Zhang C, Huang Y, Ma L, Zhao S. Effect of PPARγ on oxidative stress in diabetes-related dry eye. Exp Eye Res 2023; 231:109498. [PMID: 37169280 DOI: 10.1016/j.exer.2023.109498] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 04/08/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
Oxidative stress is closely associated with diabetes and can cause free radical accumulation and eventually lead to ocular surface tissue damage. The purpose of this study was to investigate peroxisome proliferator-activated receptor-γ (PPARγ) expression in the lacrimal gland (LG), meibomian gland, and cornea of diabetes-related dry eye mice and whether the PPARγ agonist rosiglitazone can alleviate the oxidative stress of the ocular surface, thereby improving the condition of diabetes-related dry eye. Quantitative RT-PCR (Q-PCR) showed that the PPARγ, catalase, glutathione peroxidase 3, and heme oxygenase-1 (HO-1) mRNA expression levels in the LG of diabetes-related dry eye mice decreased at 8 and 12 weeks. In addition, the increased levels of oxidative stress were confirmed by western blot. Although the mRNA expression levels of antioxidant enzymes in the cornea and meibomian gland decreased at 8 weeks, some of them recovered by 12 weeks. Rosiglitazone alleviated ocular surface damage and increased corneal sensitivity and tear production in diabetes-related dry eye mice. Moreover, the reactive oxygen species accumulation was reduced and the PPARγ, HO-1, and glutathione peroxidase 3 mRNA expression levels were increased in the LG. The PPARγ, HO-1, translocase of the outer membrane 20, and mitochondrial transcription factor A protein levels were also significantly increased. These results demonstrated that rosiglitazone reduced oxidative stress in the LG of diabetes-related dry eye mice, at least in part, by activating PPARγ to up-regulate antioxidant enzyme expression.
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Affiliation(s)
- Jing Wang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Shuangping Chen
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Xiuxiu Zhao
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China; Department of Ophthalmology, Tianjin Prevention and Treatment Center for Occupational Diseases, Tianjin, 300011, China
| | - Qian Guo
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Ruibo Yang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Chen Zhang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Yue Huang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Lechong Ma
- Department of Molecular Cell and Department Biology, California State University Los Angeles, Los Angeles, CA, USA
| | - Shaozhen Zhao
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China.
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23
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Jing W, Chen C, Wang G, Han M, Chen S, Jiang X, Shi C, Sun P, Yang Z, Shi B, Jiang X. Metabolic Modulation of Intracellular Ammonia via Intravesical Instillation of Nanoporter-Encased Hydrogel Eradicates Bladder Carcinoma. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2206893. [PMID: 36775865 PMCID: PMC10131795 DOI: 10.1002/advs.202206893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/25/2023] [Indexed: 06/18/2023]
Abstract
Tumor protein 53 (TP53) mutation in bladder carcinoma (BC), upregulates the transcription of carbamoyl phosphate synthetase 1 (CPS1), to reduce intracellular ammonia toxicity. To leverage ammonia combating BC, here, an intravesically perfusable nanoporter-encased hydrogel system is reported. A biomimetic fusogenic liposomalized nanoporter (FLNP) that is decorated with urea transporter-B (UT-B) is first synthesized with protonated chitosan oligosaccharide for bladder tumor-targeted co-delivery of urease and small interfering RNA targeting CPS1 (siCPS1). Mussel-inspired hydrogel featured with dual functions of bio-adhesion and injectability is then fabricated as the reservoir for intravesical immobilization of FLNP. It is found that FLNP-mediated UT-B immobilization dramatically induces urea transportation into tumor cells, and co-delivery of urease and siCPS1 significantly boosts ammonia accumulation in tumor inducing cell apoptosis. Treatment with hybrid system exhibits superior anti-tumor effect in orthotopic bladder tumor mouse model and patient-derived xenograft model, respectively. Combined with high-protein diet, the production of urinary urea increases, leading to an augmented intracellular deposition of ammonia in BC cells, and ultimately an enhanced tumor inhibition. Together, the work establishes that cascade modulation of ammonia in tumor cells could induce tumor apoptosis and may be a practical strategy for eradication of TP53-mutated bladder cancer.
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Affiliation(s)
- Weiqiang Jing
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Chen Chen
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Ganyu Wang
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Maosen Han
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Shouzhen Chen
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Xin Jiang
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Chongdeng Shi
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Peng Sun
- Shandong University of Traditional Chinese MedicineUniversity RoadJinanShandong Province250355China
| | - Zhenmei Yang
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Benkang Shi
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
| | - Xinyi Jiang
- Department of UrologyQilu HospitalCheeloo College of MedicineNMPA Key Laboratory for Technology Research and Evaluation of Drug Products and Key Laboratory of Chemical Biology (Ministry of Education)Department of PharmaceuticsSchool of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityCultural West RoadJinanShandong Province250012China
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24
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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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25
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Kim DB, Na C, Hwang I, Lee DW. Understanding protein translocation across chloroplast membranes: Translocons and motor proteins. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:408-416. [PMID: 36223071 DOI: 10.1111/jipb.13385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Subcellular organelles in eukaryotes are surrounded by lipid membranes. In an endomembrane system, vesicle trafficking is the primary mechanism for the delivery of organellar proteins to specific organelles. However, organellar proteins for chloroplasts, mitochondria, the nucleus, and peroxisomes that are translated in the cytosol are directly imported into their target organelles. Chloroplasts are a plant-specific organelle with outer and inner envelope membranes, a dual-membrane structure that is similar to mitochondria. Interior chloroplast proteins translated by cytosolic ribosomes are thus translocated through TOC and TIC complexes (translocons in the outer and inner envelope of chloroplasts, respectively), with stromal ATPase motor proteins playing a critical role in pulling pre-proteins through these import channels. Over the last three decades, the identity and function of TOC/TIC components and stromal motor proteins have been actively investigated, which has shed light on the action mechanisms at a molecular level. However, there remains some disagreement over the exact composition of TIC complexes and genuine stromal motor proteins. In this review, we discuss recent findings on the mechanisms by which proteins are translocated through TOC/TIC complexes and discuss future prospects for this field of research.
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Affiliation(s)
- Da Been Kim
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, 61186, Korea
| | - Changhee Na
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, 61186, Korea
| | - Inhwan Hwang
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Korea
| | - Dong Wook Lee
- Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, 61186, Korea
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju, 61186, Korea
- Kumho Life Science Laboratory, Chonnam National University, Gwangju, 61186, Korea
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26
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Shan SO. Role of Hsp70 in Post-Translational Protein Targeting: Tail-Anchored Membrane Proteins and Beyond. Int J Mol Sci 2023; 24:1170. [PMID: 36674686 PMCID: PMC9866221 DOI: 10.3390/ijms24021170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/02/2023] [Accepted: 01/04/2023] [Indexed: 01/11/2023] Open
Abstract
The Hsp70 family of molecular chaperones acts as a central 'hub' in the cell that interacts with numerous newly synthesized proteins to assist in their biogenesis. Apart from its central and well-established role in facilitating protein folding, Hsp70s also act as key decision points in the cellular chaperone network that direct client proteins to distinct biogenesis and quality control pathways. In this paper, we review accumulating data that illustrate a new branch in the Hsp70 network: the post-translational targeting of nascent membrane and organellar proteins to diverse cellular organelles. Work in multiple pathways suggests that Hsp70, via its ability to interact with components of protein targeting and translocation machineries, can initiate elaborate substrate relays in a sophisticated cascade of chaperones, cochaperones, and receptor proteins, and thus provide a mechanism to safeguard and deliver nascent membrane proteins to the correct cellular membrane. We discuss the mechanistic principles gleaned from better-studied Hsp70-dependent targeting pathways and outline the observations and outstanding questions in less well-studied systems.
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Affiliation(s)
- Shu-Ou Shan
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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27
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Han X, Maita N, Shimada A, Kohda D. Effects of targeting signal mutations in a mitochondrial presequence on the spatial distribution of the conformational ensemble in the binding site of Tom20. Protein Sci 2022; 31:e4433. [PMID: 36173160 PMCID: PMC9490799 DOI: 10.1002/pro.4433] [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: 06/22/2022] [Revised: 07/28/2022] [Accepted: 08/24/2022] [Indexed: 11/08/2022]
Abstract
The 20-kDa TOM (translocase of outer mitochondrial membrane) subunit, Tom20, is the first receptor of the protein import pathway into mitochondria. Tom20 recognizes the mitochondrial targeting signal embedded in the presequences attached to mature mitochondrial proteins, as an N-terminal extension. Consequently, ~1,000 different mitochondrial proteins are sorted into the mitochondrial matrix, and distinguished from non-mitochondrial proteins. We previously reported the MPRIDE (multiple partial recognitions in dynamic equilibrium) mechanism to explain the structural basis of the promiscuous recognition of presequences by Tom20. A subset of the targeting signal features is recognized in each pose of the presequence in the binding state, and all of the features are collectively recognized in the dynamic equilibrium between the poses. Here, we changed the volumes of the hydrophobic side chains in the targeting signal, while maintaining the binding affinity. We tethered the mutated presequences to the binding site of Tom20 and placed them in the crystal contact-free space (CCFS) created in the crystal lattice. The spatial distributions of the mutated presequences were visualized as smeared electron densities in the low-pass filtered difference maps obtained by X-ray crystallography. The mutated presequence ensembles shifted their positions in the binding state to accommodate the larger side chains, thus providing positive evidence supporting the use of the MPRIDE mechanism in the promiscuous recognition by Tom20.
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Affiliation(s)
- Xiling Han
- Division of Structural Biology, Medical Institute of BioregulationKyushu UniversityFukuokaJapan
| | - Nobuo Maita
- Division of Structural Biology, Medical Institute of BioregulationKyushu UniversityFukuokaJapan
- Institute for Quantum Life Science, National Institutes for Quantum Science and TechnologyChibaJapan
| | - Atsushi Shimada
- Division of Structural Biology, Medical Institute of BioregulationKyushu UniversityFukuokaJapan
| | - Daisuke Kohda
- Division of Structural Biology, Medical Institute of BioregulationKyushu UniversityFukuokaJapan
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