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Ruffatto K, da Silva LCO, Neves CDO, Kuntzler SG, de Lima JC, Almeida FA, Silveira V, Corrêa FM, Minello LVP, Johann L, Sperotto RA. Unravelling soybean responses to early and late Tetranychus urticae (Acari: Tetranychidae) infestation. PLANT BIOLOGY (STUTTGART, GERMANY) 2024. [PMID: 39250320 DOI: 10.1111/plb.13717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 08/16/2024] [Indexed: 09/11/2024]
Abstract
Soybean is a crucial source of food, protein, and oil worldwide that is facing challenges from biotic stresses. Infestation of Tetranychus urticae Koch (Acari: Tetranychidae) stands out as detrimentally affecting plant growth and grain production. Understanding soybean responses to T. urticae infestation is pivotal for unravelling the dynamics of mite-plant interactions. We evaluated the physiological and molecular responses of soybean plants to mite infestation after 5 and 21 days. We employed visual/microscopy observations of leaf damage, H2O2 accumulation, and lipid peroxidation. Additionally, the impact of mite infestation on shoot length/dry weight, chlorophyll concentration, and development stages was analysed. Proteomic analysis identified differentially abundant proteins (DAPs) after early (5 days) and late (21 days) infestation. Furthermore, GO, KEGG, and protein-protein interaction analyses were performed to understand effects on metabolic pathways. Throughout the analysed period, symptoms of leaf damage, H2O2 accumulation, and lipid peroxidation consistently increased. Mite infestation reduced shoot length/dry weight, chlorophyll concentration, and development stage duration. Proteomics revealed 185 and 266 DAPs after early and late mite infestation, respectively, indicating a complex remodelling of metabolic pathways. Photorespiration, chlorophyll synthesis, amino acid metabolism, and Krebs cycle/energy production were impacted after both early and late infestation. Additionally, specific metabolic pathways were modified only after early or late infestation. This study underscores the detrimental effects of mite infestation on soybean physiology and metabolism. DAPs offer potential in breeding programs for enhanced resistance. Overall, this research highlights the complex nature of soybean response to mite infestation, providing insights for intervention and breeding strategies.
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Affiliation(s)
- K Ruffatto
- Graduate Program in Biotechnology, University of Vale do Taquari - Univates, Lajeado, Brazil
| | - L C O da Silva
- Life Sciences Area, University of Vale do Taquari - Univates, Lajeado, Brazil
| | - C D O Neves
- Life Sciences Area, University of Vale do Taquari - Univates, Lajeado, Brazil
| | - S G Kuntzler
- Graduate Program in Biotechnology, University of Vale do Taquari - Univates, Lajeado, Brazil
| | - J C de Lima
- Graduate Program in Biotechnology, University of Vale do Taquari - Univates, Lajeado, Brazil
| | - F A Almeida
- Laboratory of Biotechnology, Bioscience and Biotechnology Center (CBB), State University of Northern Rio de Janeiro Darcy Ribeiro (UENF), Campos dos Goytacazes, Brazil
| | - V Silveira
- Laboratory of Biotechnology, Bioscience and Biotechnology Center (CBB), State University of Northern Rio de Janeiro Darcy Ribeiro (UENF), Campos dos Goytacazes, Brazil
| | - F M Corrêa
- Graduate Program in Plant Physiology, Federal University of Pelotas, Pelotas, Brazil
| | - L V P Minello
- Graduate Program in Plant Physiology, Federal University of Pelotas, Pelotas, Brazil
| | - L Johann
- Graduate Program in Biotechnology, University of Vale do Taquari - Univates, Lajeado, Brazil
- Life Sciences Area, University of Vale do Taquari - Univates, Lajeado, Brazil
| | - R A Sperotto
- Graduate Program in Plant Physiology, Federal University of Pelotas, Pelotas, Brazil
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Gao X, Feng B, Du C, Hou C, Jin S, Tang D, Zhu J, Lv Y. Expression dynamics indicate the involvement of SPG7 in the reproduction and spermiogenesis of Phascolosoma esculenta. Gene 2024; 895:148028. [PMID: 38007160 DOI: 10.1016/j.gene.2023.148028] [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: 06/28/2023] [Revised: 11/17/2023] [Accepted: 11/22/2023] [Indexed: 11/27/2023]
Abstract
Spastic paraplegia 7 (SPG7) is an m-AAA protease subunit involved in mitochondrial morphology and physiology. However, its function in animal reproduction is yet to be evaluated. In this study, its molecular features, subcellular localization, and expression dynamics were investigated to analyze its potential function in the reproduction of male Phascolosoma esculenta, an economically important marine species in China. The full-length cDNA of P. esculenta spg7 (Pe-spg7) measures 3053 bp and encodes an 853-amino acid protein (Pe-SPG7). Pe-SPG7 includes two transmembrane domains, an AAA domain and a proteolytic domain. Amino acid sequence alignment revealed that SPG7 was conserved during evolution. The mRNA and protein expression of spg7 indicated its involvement in reproduction. Its expression was the highest in coelomic fluid, where spermatids develop, and it was significantly higher in the breeding stage than in the nonbreeding stage. SPG7 was mainly found in the mitochondria of spermatids in the coelomic fluid, indicating that it functions in this organelle in spermatids. Immunofluorescence experiments showed that SPG7 was expressed and colocalized in the mitochondria during spermiogenesis, suggesting its involvement in P. esculenta spermiogenesis. Therefore, SPG7 may participate in spermiogenesis by functioning in the mitochondria and regulate the reproduction of male P. esculenta. This study provided insights into the function of SPG7 in animal reproduction and P. esculenta gametogenesis.
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Affiliation(s)
- Xinming Gao
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China; College of Ecology, Lishui University, Lishui, Zhejiang, 323000, People's Republic of China
| | - Binbin Feng
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
| | - Chen Du
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
| | - Congcong Hou
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
| | - Shan Jin
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China
| | - Daojun Tang
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China.
| | - Junquan Zhu
- Key Laboratory of Applied Marine Biotechnology by the Ministry of Education and Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China.
| | - Yaoping Lv
- College of Ecology, Lishui University, Lishui, Zhejiang, 323000, People's Republic of China.
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Wu Y, Li M, Ying H, Gu Y, Zhu Y, Gu Y, Huang L. Mitochondrial quality control alterations and placenta-related disorders. Front Physiol 2024; 15:1344951. [PMID: 38390447 PMCID: PMC10883312 DOI: 10.3389/fphys.2024.1344951] [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: 11/27/2023] [Accepted: 01/17/2024] [Indexed: 02/24/2024] Open
Abstract
Mitochondria are ubiquitous in eukaryotic cells. Normal maintenance of function is the premise and basis for various physiological activities. Mitochondrial dysfunction is commonly observed in a wide range of pathological conditions, such as neurodegenerative, metabolic, cardiovascular, and various diseases related to foetal growth and development. The placenta is a highly energy-dependent organ that acts as an intermediary between the mother and foetus and functions to maintain foetal growth and development. Recent studies have demonstrated that mitochondrial dysfunction is associated with placental disorders. Defects in mitochondrial quality control mechanisms may lead to preeclampsia and foetal growth restriction. In this review, we address the quality control mechanisms of mitochondria and the relevant pathologies of mitochondrial dysfunction in placenta-related diseases, such as preeclampsia and foetal growth restriction. This review also investigates the relation between mitochondrial dysfunction and placental disorders.
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Affiliation(s)
- Yamei Wu
- Wuxi Maternity and Child Healthcare Hospital, Affiliated Women's Hospital of Jiangnan University, Wuxi, China
- Wuxi Clinical Medical College of Nanjing Medical University, Wuxi, China
| | - Meng Li
- Wuxi Maternity and Child Healthcare Hospital, Affiliated Women's Hospital of Jiangnan University, Wuxi, China
- Wuxi Clinical Medical College of Nanjing Medical University, Wuxi, China
| | - Hao Ying
- Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| | - Ying Gu
- Wuxi Maternity and Child Healthcare Hospital, Affiliated Women's Hospital of Jiangnan University, Wuxi, China
- Wuxi Clinical Medical College of Nanjing Medical University, Wuxi, China
| | - Yunlong Zhu
- Wuxi Maternity and Child Healthcare Hospital, Affiliated Women's Hospital of Jiangnan University, Wuxi, China
- Wuxi Clinical Medical College of Nanjing Medical University, Wuxi, China
| | - Yanfang Gu
- Wuxi Maternity and Child Healthcare Hospital, Affiliated Women's Hospital of Jiangnan University, Wuxi, China
- Wuxi Clinical Medical College of Nanjing Medical University, Wuxi, China
| | - Lu Huang
- Wuxi Maternity and Child Healthcare Hospital, Affiliated Women's Hospital of Jiangnan University, Wuxi, China
- Wuxi Clinical Medical College of Nanjing Medical University, Wuxi, China
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Nusir A, Sinclair P, Kabbani N. Mitochondrial Proteomes in Neural Cells: A Systematic Review. Biomolecules 2023; 13:1638. [PMID: 38002320 PMCID: PMC10669788 DOI: 10.3390/biom13111638] [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: 10/10/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
Mitochondria are ancient endosymbiotic double membrane organelles that support a wide range of eukaryotic cell functions through energy, metabolism, and cellular control. There are over 1000 known proteins that either reside within the mitochondria or are transiently associated with it. These mitochondrial proteins represent a functional subcellular protein network (mtProteome) that is encoded by mitochondrial and nuclear genomes and significantly varies between cell types and conditions. In neurons, the high metabolic demand and differential energy requirements at the synapses are met by specific modifications to the mtProteome, resulting in alterations in the expression and functional properties of the proteins involved in energy production and quality control, including fission and fusion. The composition of mtProteomes also impacts the localization of mitochondria in axons and dendrites with a growing number of neurodegenerative diseases associated with changes in mitochondrial proteins. This review summarizes the findings on the composition and properties of mtProteomes important for mitochondrial energy production, calcium and lipid signaling, and quality control in neural cells. We highlight strategies in mass spectrometry (MS) proteomic analysis of mtProteomes from cultured cells and tissue. The research into mtProteome composition and function provides opportunities in biomarker discovery and drug development for the treatment of metabolic and neurodegenerative disease.
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Affiliation(s)
- Aya Nusir
- Interdisciplinary Program in Neuroscience, School of Systems Biology, George Mason University, Fairfax, VA 22030, USA;
| | - Patricia Sinclair
- School of Systems Biology, George Mason University, Fairfax, VA 22030, USA;
| | - Nadine Kabbani
- Interdisciplinary Program in Neuroscience, School of Systems Biology, George Mason University, Fairfax, VA 22030, USA;
- School of Systems Biology, George Mason University, Fairfax, VA 22030, USA;
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Khalimonchuk O, Becker DF. Molecular Determinants of Mitochondrial Shape and Function and Their Role in Glaucoma. Antioxid Redox Signal 2023; 38:896-919. [PMID: 36301938 PMCID: PMC10171965 DOI: 10.1089/ars.2022.0124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/07/2022] [Accepted: 10/22/2022] [Indexed: 01/12/2023]
Abstract
Significance: Cells depend on well-functioning mitochondria for essential processes such as energy production, redox signaling, coordination of metabolic pathways, and cofactor biosynthesis. Mitochondrial dysfunction, metabolic decline, and protein stress have been implicated in the etiology of multiple late-onset diseases, including various ataxias, diabetes, sarcopenia, neuromuscular disorders, and neurodegenerative diseases such as parkinsonism, amyotrophic lateral sclerosis, and glaucoma. Recent Advances: New evidence supports that increased energy metabolism protects neuron function during aging. Key energy metabolic enzymes, however, are susceptible to oxidative damage making it imperative that the mitochondrial proteome is protected. More than 40 different enzymes have been identified as important factors for guarding mitochondrial health and maintaining a dynamic pool of mitochondria. Critical Issues: Understanding shared mechanisms of age-related disorders of neurodegenerative diseases such as glaucoma, Alzheimer's disease, and Parkinson's disease is important for developing new therapies. Functional mitochondrial shape and dynamics rely on complex interactions between mitochondrial proteases and membrane proteins. Identifying the sequence of molecular events that lead to mitochondrial dysfunction and metabolic stress is a major challenge. Future Directions: A critical need exists for new strategies that reduce mitochondrial protein stress and promote mitochondrial dynamics in age-related neurological disorders. Discovering how mitochondria-associated degradation is related to proteostatic mechanisms in mitochondrial compartments may reveal new opportunities for therapeutic interventions. Also, little is known about how protein and membrane contacts in the inner and outer mitochondrial membrane are regulated, even though they are pivotal for mitochondrial architecture. Future work will need to delineate the molecular details of these processes.
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Affiliation(s)
- Oleh Khalimonchuk
- Department of Biochemistry, University of Nebraska–Lincoln, Lincoln, Nebraska, USA
- Department of Biochemistry and Nebraska Redox Biology Center, University of Nebraska–Lincoln, Lincoln, Nebraska, USA
- Fred & Pamela Buffett Cancer Center, Omaha, Nebraska, USA
| | - Donald F. Becker
- Department of Biochemistry, University of Nebraska–Lincoln, Lincoln, Nebraska, USA
- Department of Biochemistry and Nebraska Redox Biology Center, University of Nebraska–Lincoln, Lincoln, Nebraska, USA
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Pareek G. AAA+ proteases: the first line of defense against mitochondrial damage. PeerJ 2022; 10:e14350. [PMID: 36389399 PMCID: PMC9648348 DOI: 10.7717/peerj.14350] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 10/16/2022] [Indexed: 11/09/2022] Open
Abstract
Mitochondria play essential cellular roles in Adenosine triphosphate (ATP) synthesis, calcium homeostasis, and metabolism, but these vital processes have potentially deadly side effects. The production of the reactive oxygen species (ROS) and the aggregation of misfolded mitochondrial proteins can lead to severe mitochondrial damage and even cell death. The accumulation of mitochondrial damage is strongly implicated in aging and several incurable diseases, including neurodegenerative disorders and cancer. To oppose this, metazoans utilize a variety of quality control strategies, including the degradation of the damaged mitochondrial proteins by the mitochondrial-resident proteases of the ATPase Associated with the diverse cellular Activities (AAA+) family. This mini-review focuses on the quality control mediated by the mitochondrial-resident proteases of the AAA+ family used to combat the accumulation of damaged mitochondria and on how the failure of this mitochondrial quality control contributes to diseases.
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Sharma N, Osman C. Yme2, a putative RNA recognition motif and AAA+ domain containing protein, genetically interacts with the mitochondrial protein export machinery. Biol Chem 2022; 403:807-817. [PMID: 35100666 PMCID: PMC9284673 DOI: 10.1515/hsz-2021-0398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 01/19/2022] [Indexed: 02/04/2023]
Abstract
The mitochondrial respiratory chain is composed of nuclear as well as mitochondrial-encoded subunits. A variety of factors mediate co-translational integration of mtDNA-encoded proteins into the inner membrane. In Saccharomyces cerevisiae, Mdm38 and Mba1 are ribosome acceptors that recruit the mitochondrial ribosome to the inner membrane, where the insertase Oxa1, facilitates membrane integration of client proteins. The protein Yme2 has previously been shown to be localized in the inner mitochondrial membrane and has been implicated in mitochondrial protein biogenesis, but its mode of action remains unclear. Here, we show that multiple copies of Yme2 assemble into a high molecular weight complex. Using a combination of bioinformatics and mutational analyses, we find that Yme2 possesses an RNA recognition motif (RRM), which faces the mitochondrial matrix and a AAA+ domain that is located in the intermembrane space. We further show that YME2 genetically interacts with MDM38, MBA1 and OXA1, which links the function of Yme2 to the mitochondrial protein biogenesis machinery.
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Affiliation(s)
- Nupur Sharma
- Faculty of Biology, Ludwig Maximilian University Munich, D-82152Planegg-Martinsried, Germany
- Graduate School of Life Sciences, Ludwig Maximilian University Munich, D-82152Planegg-Martinsried, Germany
| | - Christof Osman
- Faculty of Biology, Ludwig Maximilian University Munich, D-82152Planegg-Martinsried, Germany
- Graduate School of Life Sciences, Ludwig Maximilian University Munich, D-82152Planegg-Martinsried, Germany
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Yi L, Liu B, Nixon PJ, Yu J, Chen F. Recent Advances in Understanding the Structural and Functional Evolution of FtsH Proteases. FRONTIERS IN PLANT SCIENCE 2022; 13:837528. [PMID: 35463435 PMCID: PMC9020784 DOI: 10.3389/fpls.2022.837528] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/24/2022] [Indexed: 05/18/2023]
Abstract
The FtsH family of proteases are membrane-anchored, ATP-dependent, zinc metalloproteases. They are universally present in prokaryotes and the mitochondria and chloroplasts of eukaryotic cells. Most bacteria bear a single ftsH gene that produces hexameric homocomplexes with diverse house-keeping roles. However, in mitochondria, chloroplasts and cyanobacteria, multiple FtsH homologs form homo- and heterocomplexes with specialized functions in maintaining photosynthesis and respiration. The diversification of FtsH homologs combined with selective pairing of FtsH isomers is a versatile strategy to enable functional adaptation. In this article we summarize recent progress in understanding the evolution, structure and function of FtsH proteases with a focus on the role of FtsH in photosynthesis and respiration.
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Affiliation(s)
- Lanbo Yi
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen, China
| | - Bin Liu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen, China
| | - Peter J. Nixon
- Sir Ernst Chain Building-Wolfson Laboratories, Department of Life Sciences, Imperial College London, London, United Kingdom
- *Correspondence: Peter J. Nixon, ; orcid.org/0000-0003-1952-6937
| | - Jianfeng Yu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Sir Ernst Chain Building-Wolfson Laboratories, Department of Life Sciences, Imperial College London, London, United Kingdom
- Jianfeng Yu, ; orcid.org/0000-0001-7174-3803
| | - Feng Chen
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Institute for Innovative Development of Food Industry, Shenzhen University, Shenzhen, China
- Feng Chen, ; orcid.org/0000-0002-9054-943X
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Abstract
In this Primer, Seraphim and Houry highlight the structural features and functional diversity of AAA+ proteins and summarise our current knowledge of the molecular mechanisms driving the activities of these proteins.
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Affiliation(s)
- Thiago V Seraphim
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Walid A Houry
- Department of Biochemistry, University of Toronto, Toronto, ON M5G 1M1, Canada; Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.
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10
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Carvalho V, Prabudiansyah I, Kovacik L, Chami M, Kieffer R, van der Valk R, de Lange N, Engel A, Aubin-Tam ME. The cytoplasmic domain of the AAA+ protease FtsH is tilted with respect to the membrane to facilitate substrate entry. J Biol Chem 2021; 296:100029. [PMID: 33154162 PMCID: PMC7949044 DOI: 10.1074/jbc.ra120.014739] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 10/28/2020] [Accepted: 11/05/2020] [Indexed: 11/06/2022] Open
Abstract
AAA+ proteases are degradation machines that use ATP hydrolysis to unfold protein substrates and translocate them through a central pore toward a degradation chamber. FtsH, a bacterial membrane-anchored AAA+ protease, plays a vital role in membrane protein quality control. How substrates reach the FtsH central pore is an open key question that is not resolved by the available atomic structures of cytoplasmic and periplasmic domains. In this work, we used both negative stain TEM and cryo-EM to determine 3D maps of the full-length Aquifex aeolicus FtsH protease. Unexpectedly, we observed that detergent solubilization induces the formation of fully active FtsH dodecamers, which consist of two FtsH hexamers in a single detergent micelle. The striking tilted conformation of the cytosolic domain in the FtsH dodecamer visualized by negative stain TEM suggests a lateral substrate entrance between the membrane and cytosolic domain. Such a substrate path was then resolved in the cryo-EM structure of the FtsH hexamer. By mapping the available structural information and structure predictions for the transmembrane helices to the amino acid sequence we identified a linker of ∼20 residues between the second transmembrane helix and the cytosolic domain. This unique polypeptide appears to be highly flexible and turned out to be essential for proper functioning of FtsH as its deletion fully eliminated the proteolytic activity of FtsH.
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Affiliation(s)
- Vanessa Carvalho
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Irfan Prabudiansyah
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Lubomir Kovacik
- BioEM Lab, C-CINA, Center for Cellular Imaging and NanoAnalytics, Biozentrum, University of Basel, Basel, Switzerland
| | - Mohamed Chami
- BioEM Lab, C-CINA, Center for Cellular Imaging and NanoAnalytics, Biozentrum, University of Basel, Basel, Switzerland
| | - Roland Kieffer
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Ramon van der Valk
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Nick de Lange
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Andreas Engel
- BioEM Lab, C-CINA, Center for Cellular Imaging and NanoAnalytics, Biozentrum, University of Basel, Basel, Switzerland.
| | - Marie-Eve Aubin-Tam
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands.
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11
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Human CLPB forms ATP-dependent complexes in the mitochondrial intermembrane space. Int J Biochem Cell Biol 2020; 127:105841. [PMID: 32866687 DOI: 10.1016/j.biocel.2020.105841] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/22/2020] [Accepted: 08/24/2020] [Indexed: 02/07/2023]
Abstract
Human caseinolytic peptidase B protein homolog (CLPB), also known as suppressor of potassium transport defect 3 (SKD3), is a broadly-expressed member of the family of ATPases associated with diverse cellular activities (AAA+). Mutations in the human CLPB gene cause 3-methylglutaconic aciduria type VII. CLPB is upregulated in acute myeloid leukemia (AML), where it contributes to anti-cancer drug resistance. The biological function of CLPB in human cells and mechanistic links to the clinical phenotypes are currently unknown. Herein, subcellular fractionation of human HEK-293 and BT-549 cells showed that a single 57-kDa form of CLPB was present in the mitochondria and not in the cytosolic fraction. Immunofluorescence staining of HEK-293 and BT-549 cells with anti-CLPB antibody co-localized with the mitochondrial staining using a MitoTracker dye. In purified intact mitochondria, CLPB was protected against externally added proteinase K, but it was susceptible to degradation after disruption of the outer membrane, indicating that CLPB resides in the mitochondrial intermembrane space. Overexpressed CLPB, while properly trafficked to the mitochondria, appeared to form large clusters/aggregates that were resistant to extraction with non-ionic detergents and were readily visualized by immunofluorescence microscopy. Importantly, endogenous CLPB formed high molecular weight protein complexes in an ATP-dependent manner that were detected by blue native polyacrylamide gel electrophoresis. These results demonstrate that ATP induces a structural change in CLPB and controls its ability to self-associate or form complexes with other proteins in the intermembrane space of mitochondria.
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12
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Tjahjono E, McAnena AP, Kirienko NV. The evolutionarily conserved ESRE stress response network is activated by ROS and mitochondrial damage. BMC Biol 2020; 18:74. [PMID: 32600387 PMCID: PMC7322875 DOI: 10.1186/s12915-020-00812-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 06/17/2020] [Indexed: 02/07/2023] Open
Abstract
Background Mitochondrial dysfunction causes or contributes to a wide variety of pathologies, including neurodegenerative diseases, cancer, metabolic diseases, and aging. Cells actively surveil a number of mitochondrial readouts to ensure that cellular homeostasis is maintained. Results In this article, we characterize the role of the ethanol and stress response element (ESRE) pathway in mitochondrial surveillance and show that it is robustly activated when the concentration of reactive oxygen species (ROS) in the cell increases. While experiments were mostly performed in Caenorhabditis elegans, we observed similar gene activation profile in human cell lines. The linear relationship between ROS and ESRE activation differentiates ESRE from known mitochondrial surveillance pathways, such as the mitochondrial unfolded protein response (UPRmt), which monitor mitochondrial protein import. The ability of the ESRE network to be activated by increased ROS allows the cell to respond to oxidative and reductive stresses. The ESRE network works in tandem with other mitochondrial surveillance mechanisms as well, in a fashion that suggests a partially redundant hierarchy. For example, mutation of the UPRmt pathway results in earlier and more robust activation of the ESRE pathway. Interestingly, full expression of ATFS-1, a key transcription factor for the UPRmt, requires the presence of an ESRE motif in its promoter region. Conclusion The ESRE pathway responds to mitochondrial damage by monitoring ROS levels. This response is conserved in humans. The ESRE pathway is activated earlier when other mitochondrial surveillance pathways are unavailable during mitochondrial crises, potentially to mitigate stress and restore health. However, the exact mechanisms of pathway activation and crosstalk remain to be elucidated. Ultimately, a better understanding of this network, and its role in the constellation of mitochondrial and cellular stress networks, will improve healthspan.
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Affiliation(s)
- Elissa Tjahjono
- Department of BioSciences, Rice University, 6100 Main St, MS140, Houston, TX, 77005, USA
| | - Aidan P McAnena
- Department of BioSciences, Rice University, 6100 Main St, MS140, Houston, TX, 77005, USA
| | - Natalia V Kirienko
- Department of BioSciences, Rice University, 6100 Main St, MS140, Houston, TX, 77005, USA.
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