1
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Meng K, Yang J, Xue J, Lv J, Zhu P, Shi L, Li S. A host E3 ubiquitin ligase regulates Salmonella virulence by targeting an SPI-2 effector involved in SIF biogenesis. MLIFE 2023; 2:141-158. [PMID: 38817622 PMCID: PMC10989757 DOI: 10.1002/mlf2.12063] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/05/2023] [Accepted: 02/26/2023] [Indexed: 06/01/2024]
Abstract
Salmonella Typhimurium creates an intracellular niche for its replication by utilizing a large cohort of effectors, including several that function to interfere with host ubiquitin signaling. Although the mechanism of action of many such effectors has been elucidated, how the interplay between the host ubiquitin network and bacterial virulence factors dictates the outcome of infection largely remains undefined. In this study, we found that the SPI-2 effector SseK3 inhibits SNARE pairing to promote the formation of a Salmonella-induced filament by Arg-GlcNAcylation of SNARE proteins, including SNAP25, VAMP8, and Syntaxin. Further study reveals that host cells counteract the activity of SseK3 by inducing the expression of the E3 ubiquitin ligase TRIM32, which catalyzes K48-linked ubiquitination on SseK3 and targets its membrane-associated portion for degradation. Hence, TRIM32 antagonizes SNAP25 Arg-GlcNAcylation induced by SseK3 to restrict Salmonella-induced filament biogenesis and Salmonella replication. Our study reveals a mechanism by which host cells inhibit bacterial replication by eliminating specific virulence factors.
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Affiliation(s)
- Kun Meng
- Institute of Infection and Immunity, Taihe HospitalHubei University of MedicineShiyanChina
| | - Jin Yang
- Institute of Infection and Immunity, Taihe HospitalHubei University of MedicineShiyanChina
| | - Juan Xue
- Institute of Infection and Immunity, Taihe HospitalHubei University of MedicineShiyanChina
| | - Jun Lv
- Institute of Infection and Immunity, Taihe HospitalHubei University of MedicineShiyanChina
| | - Ping Zhu
- Institute of Infection and Immunity, Taihe HospitalHubei University of MedicineShiyanChina
| | - Liuliu Shi
- School of Basic Medical ScienceHubei University of MedicineShiyanChina
| | - Shan Li
- Institute of Infection and Immunity, Taihe HospitalHubei University of MedicineShiyanChina
- State Key Laboratory of Agricultural Microbiology, College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- College of Biomedicine and HealthHuazhong Agricultural UniversityWuhanChina
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2
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Mendoza A, Karch J. Keeping the beat against time: Mitochondrial fitness in the aging heart. FRONTIERS IN AGING 2022; 3:951417. [PMID: 35958271 PMCID: PMC9360554 DOI: 10.3389/fragi.2022.951417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/30/2022] [Indexed: 11/21/2022]
Abstract
The process of aging strongly correlates with maladaptive architectural, mechanical, and biochemical alterations that contribute to the decline in cardiac function. Consequently, aging is a major risk factor for the development of heart disease, the leading cause of death in the developed world. In this review, we will summarize the classic and recently uncovered pathological changes within the aged heart with an emphasis on the mitochondria. Specifically, we describe the metabolic changes that occur in the aging heart as well as the loss of mitochondrial fitness and function and how these factors contribute to the decline in cardiomyocyte number. In addition, we highlight recent pharmacological, genetic, or behavioral therapeutic intervention advancements that may alleviate age-related cardiac decline.
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Affiliation(s)
- Arielys Mendoza
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX, United States
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, United States
| | - Jason Karch
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX, United States
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, United States
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3
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Guo X. Localized Proteasomal Degradation: From the Nucleus to Cell Periphery. Biomolecules 2022; 12:biom12020229. [PMID: 35204730 PMCID: PMC8961600 DOI: 10.3390/biom12020229] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 12/31/2022] Open
Abstract
The proteasome is responsible for selective degradation of most cellular proteins. Abundantly present in the cell, proteasomes not only diffuse in the cytoplasm and the nucleus but also associate with the chromatin, cytoskeleton, various membranes and membraneless organelles/condensates. How and why the proteasome gets to these specific subcellular compartments remains poorly understood, although increasing evidence supports the hypothesis that intracellular localization may have profound impacts on the activity, substrate accessibility and stability/integrity of the proteasome. In this short review, I summarize recent advances on the functions, regulations and targeting mechanisms of proteasomes, especially those localized to the nuclear condensates and membrane structures of the cell, and I discuss the biological significance thereof in mediating compartmentalized protein degradation.
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Affiliation(s)
- Xing Guo
- Life Sciences Institute, Zhejiang University, Hangzhou 310058, China;
- Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Hangzhou 310058, China
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4
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Choubey V, Zeb A, Kaasik A. Molecular Mechanisms and Regulation of Mammalian Mitophagy. Cells 2021; 11:38. [PMID: 35011599 PMCID: PMC8750762 DOI: 10.3390/cells11010038] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/17/2021] [Accepted: 12/20/2021] [Indexed: 02/07/2023] Open
Abstract
Mitochondria in the cell are the center for energy production, essential biomolecule synthesis, and cell fate determination. Moreover, the mitochondrial functional versatility enables cells to adapt to the changes in cellular environment and various stresses. In the process of discharging its cellular duties, mitochondria face multiple types of challenges, such as oxidative stress, protein-related challenges (import, folding, and degradation) and mitochondrial DNA damage. They mitigate all these challenges with robust quality control mechanisms which include antioxidant defenses, proteostasis systems (chaperones and proteases) and mitochondrial biogenesis. Failure of these quality control mechanisms leaves mitochondria as terminally damaged, which then have to be promptly cleared from the cells before they become a threat to cell survival. Such damaged mitochondria are degraded by a selective form of autophagy called mitophagy. Rigorous research in the field has identified multiple types of mitophagy processes based on targeting signals on damaged or superfluous mitochondria. In this review, we provide an in-depth overview of mammalian mitophagy and its importance in human health and diseases. We also attempted to highlight the future area of investigation in the field of mitophagy.
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Affiliation(s)
- Vinay Choubey
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, Ravila 19, 50411 Tartu, Estonia; (A.Z.); (A.K.)
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5
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Protein and Mitochondria Quality Control Mechanisms and Cardiac Aging. Cells 2020; 9:cells9040933. [PMID: 32290135 PMCID: PMC7226975 DOI: 10.3390/cells9040933] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/07/2020] [Accepted: 04/07/2020] [Indexed: 12/31/2022] Open
Abstract
Cardiovascular disease (CVD) is the number one cause of death in the United States. Advancing age is a primary risk factor for developing CVD. Estimates indicate that 20% of the US population will be ≥65 years old by 2030. Direct expenditures for treating CVD in the older population combined with indirect costs, secondary to lost wages, are predicted to reach $1.1 trillion by 2035. Therefore, there is an eminent need to discover novel therapeutic targets and identify new interventions to delay, lessen the severity, or prevent cardiovascular complications associated with advanced age. Protein and organelle quality control pathways including autophagy/lysosomal and the ubiquitin-proteasome systems, are emerging contributors of age-associated myocardial dysfunction. In general, two findings have sparked this interest. First, strong evidence indicates that cardiac protein degradation pathways are altered in the heart with aging. Second, it is well accepted that damaged and misfolded protein aggregates and dysfunctional mitochondria accumulate in the heart with age. In this review, we will: (i) define the different protein and mitochondria quality control mechanisms in the heart; (ii) provide evidence that each quality control pathway becomes dysfunctional during cardiac aging; and (iii) discuss current advances in targeting these pathways to maintain cardiac function with age.
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6
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Yoo SM, Yamashita SI, Kim H, Na D, Lee H, Kim SJ, Cho DH, Kanki T, Jung YK. FKBP8 LIRL-dependent mitochondrial fragmentation facilitates mitophagy under stress conditions. FASEB J 2019; 34:2944-2957. [PMID: 31908024 DOI: 10.1096/fj.201901735r] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 12/02/2019] [Accepted: 12/15/2019] [Indexed: 01/05/2023]
Abstract
Mitochondrial quality control maintains mitochondrial function by regulating mitochondrial dynamics and mitophagy. Despite the identification of mitochondrial quality control factors, little is known about the crucial regulators coordinating both mitochondrial fission and mitophagy. Through a cell-based functional screening assay, FK506 binding protein 8 (FKBP8) was identified to target microtubule-associated protein 1 light chain 3 (LC3) to the mitochondria and to change mitochondrial morphology. Microscopy analysis revealed that the formation of tubular and enlarged mitochondria was observed in FKBP8 knockdown HeLa cells and the cortex of Fkbp8 heterozygote-knockout mouse embryos. Under iron depletion-induced stress, FKBP8 was recruited to the site of mitochondrial division through budding and colocalized with LC3. FKBP8 was also found to be required for mitochondrial fragmentation and mitophagy under hypoxic stress. Conversely, FKBP8 overexpression induced mitochondrial fragmentation in HeLa cells, human fibroblasts and mouse embryo fibroblasts (MEFs), and this fragmentation occurred in Drp1 knockout MEF cells, FIP200 knockout HeLa cells and BNIP3/NIX double knockout HeLa cells, but not in Opa1 knockout MEFs. Interestingly, we found an LIR motif-like sequence (LIRL), as well as an LIR motif, at the N-terminus of FKBP8 and LIRL was essential for both inducing mitochondrial fragmentation and binding of FKBP8 to OPA1. Together, we suggest that FKBP8 plays an essential role in mitochondrial fragmentation through LIRL during mitophagy and this activity of FKBP8 together with LIR is required for mitophagy under stress conditions.
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Affiliation(s)
- Seung-Min Yoo
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Shun-Ichi Yamashita
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Hyunjoo Kim
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - DoHyeong Na
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Haneul Lee
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Seo Jin Kim
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Dong-Hyung Cho
- Brain Science and Engineering Institute, Kyungpook National University, Daegu, Korea
| | - Tomotake Kanki
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Yong-Keun Jung
- School of Biological Sciences, Seoul National University, Seoul, Korea
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7
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Abstract
Synthesis and regulation of lipid levels and identities is critical for a wide variety of cellular functions, including structural and morphological properties of organelles, energy storage, signaling, and stability and function of membrane proteins. Proteolytic cleavage events regulate and/or influence some of these lipid metabolic processes and as a result help modulate their pleiotropic cellular functions. Proteins involved in lipid regulation are proteolytically cleaved for the purpose of their relocalization, processing, turnover, and quality control, among others. The scope of this review includes proteolytic events governing cellular lipid dynamics. After an initial discussion of the classic example of sterol regulatory element-binding proteins, our focus will shift to the mitochondrion, where a range of proteolytic events are critical for normal mitochondrial phospholipid metabolism and enforcing quality control therein. Recently, mitochondrial phospholipid metabolic pathways have been implicated as important for the proliferative capacity of cancers. Thus, the assorted proteases that regulate, monitor, or influence the activity of proteins that are important for phospholipid metabolism represent attractive targets to be manipulated for research purposes and clinical applications.
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Affiliation(s)
- Pingdewinde N. Sam
- Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Erica Avery
- Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Steven M. Claypool
- Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
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8
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Mali GR, Yeyati PL, Mizuno S, Dodd DO, Tennant PA, Keighren MA, Zur Lage P, Shoemark A, Garcia-Munoz A, Shimada A, Takeda H, Edlich F, Takahashi S, von Kreigsheim A, Jarman AP, Mill P. ZMYND10 functions in a chaperone relay during axonemal dynein assembly. eLife 2018; 7:34389. [PMID: 29916806 PMCID: PMC6044906 DOI: 10.7554/elife.34389] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/18/2018] [Indexed: 11/13/2022] Open
Abstract
Molecular chaperones promote the folding and macromolecular assembly of a diverse set of 'client' proteins. How ubiquitous chaperone machineries direct their activities towards specific sets of substrates is unclear. Through the use of mouse genetics, imaging and quantitative proteomics we uncover that ZMYND10 is a novel co-chaperone that confers specificity for the FKBP8-HSP90 chaperone complex towards axonemal dynein clients required for cilia motility. Loss of ZMYND10 perturbs the chaperoning of axonemal dynein heavy chains, triggering broader degradation of dynein motor subunits. We show that pharmacological inhibition of FKBP8 phenocopies dynein motor instability associated with the loss of ZMYND10 in airway cells and that human disease-causing variants of ZMYND10 disrupt its ability to act as an FKBP8-HSP90 co-chaperone. Our study indicates that primary ciliary dyskinesia (PCD), caused by mutations in dynein assembly factors disrupting cytoplasmic pre-assembly of axonemal dynein motors, should be considered a cell-type specific protein-misfolding disease.
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Affiliation(s)
- Girish R Mali
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Patricia L Yeyati
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Seiya Mizuno
- Laboratory Animal Resource Centre, University of Tsukuba, Tsukuba, Japan
| | - Daniel O Dodd
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter A Tennant
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Margaret A Keighren
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Petra Zur Lage
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Amelia Shoemark
- Division of Molecular and Clinical Medicine, University of Dundee, Dundee, United Kingdom
| | | | - Atsuko Shimada
- Department of Biological Sciences, University of Tokyo, Tokyo, Japan
| | - Hiroyuki Takeda
- Department of Biological Sciences, University of Tokyo, Tokyo, Japan
| | - Frank Edlich
- Institute for Biochemistry and Molecular Biology, University of Freiburg, Freiburg, Germany.,BIOSS, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Satoru Takahashi
- Laboratory Animal Resource Centre, University of Tsukuba, Tsukuba, Japan.,Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Alex von Kreigsheim
- Systems Biology Ireland, University College Dublin, Dublin, Ireland.,Edinburgh Cancer Research UK Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrew P Jarman
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
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9
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Bragoszewski P, Turek M, Chacinska A. Control of mitochondrial biogenesis and function by the ubiquitin-proteasome system. Open Biol 2018; 7:rsob.170007. [PMID: 28446709 PMCID: PMC5413908 DOI: 10.1098/rsob.170007] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/31/2017] [Indexed: 12/17/2022] Open
Abstract
Mitochondria are pivotal organelles in eukaryotic cells. The complex proteome of mitochondria comprises proteins that are encoded by nuclear and mitochondrial genomes. The biogenesis of mitochondrial proteins requires their transport in an unfolded state with a high risk of misfolding. The mislocalization of mitochondrial proteins is deleterious to the cell. The electron transport chain in mitochondria is a source of reactive oxygen species that damage proteins. Mitochondrial dysfunction is linked to many pathological conditions and, together with the loss of cellular protein homeostasis (proteostasis), are hallmarks of ageing and ageing-related degeneration diseases. The pathogenesis of neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease, has been associated with mitochondrial and proteostasis failure. Thus, mitochondrial proteins require sophisticated surveillance mechanisms. Although mitochondria form a proteasome-exclusive compartment, multiple lines of evidence indicate a crucial role for the cytosolic ubiquitin-proteasome system (UPS) in the quality control of mitochondrial proteins. The proteasome affects mitochondrial proteins at stages of their biogenesis and maturity. The effects of the UPS go beyond the removal of damaged proteins and include the adjustment of mitochondrial proteome composition, the regulation of organelle dynamics and the protection of cellular homeostasis against mitochondrial failure. In turn, mitochondrial activity and mitochondrial dysfunction adjust the activity of the UPS, with implications at the cellular level.
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Affiliation(s)
- Piotr Bragoszewski
- Laboratory of Mitochondrial Biogenesis, International Institute of Molecular and Cell Biology, Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Michal Turek
- Laboratory of Mitochondrial Biogenesis, International Institute of Molecular and Cell Biology, Ks. Trojdena 4, 02-109 Warsaw, Poland
| | - Agnieszka Chacinska
- Laboratory of Mitochondrial Biogenesis, International Institute of Molecular and Cell Biology, Ks. Trojdena 4, 02-109 Warsaw, Poland .,Centre of New Technologies, Warsaw University, Banacha 2c, 02-097 Warsaw, Poland
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10
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Peng YJ, Huang JJ, Wu HH, Hsieh HY, Wu CY, Chen SC, Chen TY, Tang CY. Regulation of CLC-1 chloride channel biosynthesis by FKBP8 and Hsp90β. Sci Rep 2016; 6:32444. [PMID: 27580824 PMCID: PMC5007535 DOI: 10.1038/srep32444] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/10/2016] [Indexed: 01/23/2023] Open
Abstract
Mutations in human CLC-1 chloride channel are associated with the skeletal muscle disorder myotonia congenita. The disease-causing mutant A531V manifests enhanced proteasomal degradation of CLC-1. We recently found that CLC-1 degradation is mediated by cullin 4 ubiquitin ligase complex. It is currently unclear how quality control and protein degradation systems coordinate with each other to process the biosynthesis of CLC-1. Herein we aim to ascertain the molecular nature of the protein quality control system for CLC-1. We identified three CLC-1-interacting proteins that are well-known heat shock protein 90 (Hsp90)-associated co-chaperones: FK506-binding protein 8 (FKBP8), activator of Hsp90 ATPase homolog 1 (Aha1), and Hsp70/Hsp90 organizing protein (HOP). These co-chaperones promote both the protein level and the functional expression of CLC-1 wild-type and A531V mutant. CLC-1 biosynthesis is also facilitated by the molecular chaperones Hsc70 and Hsp90β. The protein stability of CLC-1 is notably increased by FKBP8 and the Hsp90β inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) that substantially suppresses cullin 4 expression. We further confirmed that cullin 4 may interact with Hsp90β and FKBP8. Our data are consistent with the idea that FKBP8 and Hsp90β play an essential role in the late phase of CLC-1 quality control by dynamically coordinating protein folding and degradation.
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Affiliation(s)
- Yi-Jheng Peng
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Jing-Jia Huang
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hao-Han Wu
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsin-Ying Hsieh
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chia-Ying Wu
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shu-Ching Chen
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Tsung-Yu Chen
- Neuroscience Center, University of California, Davis, USA
| | - Chih-Yung Tang
- Department of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, College of Medicine, National Taiwan University, Taipei, Taiwan
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11
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The life cycle of the 26S proteasome: from birth, through regulation and function, and onto its death. Cell Res 2016; 26:869-85. [PMID: 27444871 PMCID: PMC4973335 DOI: 10.1038/cr.2016.86] [Citation(s) in RCA: 213] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The 26S proteasome is a large, ∼2.5 MDa, multi-catalytic ATP-dependent protease complex that serves as the degrading arm of the ubiquitin system, which is the major pathway for regulated degradation of cytosolic, nuclear and membrane proteins in all eukaryotic organisms.
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12
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Li H, Zhang C, Cui H, Guo K, Wang F, Zhao T, Liang W, Lv Q, Zhang Y. FKBP8 interact with classical swine fever virus NS5A protein and promote virus RNA replication. Virus Genes 2016; 52:99-106. [PMID: 26748656 DOI: 10.1007/s11262-015-1286-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 09/02/2015] [Indexed: 11/24/2022]
Abstract
The non-structural 5A (NS5A) protein of classical swine fever virus (CSFV) is proven to be involved in viral replication and can also modulate cellular signaling and host cellular responses via to its ability to interact with various cellular proteins. FKBP8 is also reported to promote virus replication. Here, we show that NS5A specifically interacts with FKBP8 through coimmunoprecipitation and GST-pulldown studies. Additionally, confocal microscopy study showed that NS5A and FKBP8 colocalized in the cytoplasm. Overexpression of FKBP8 via the eukaryotic expression plasmid pDsRED N1 significantly promoted viral RNA synthesis. The cells knockdown of FKBP8 by lentivirus-mediated shRNA markedly decreased the virus replication when infected with CSFV. These data suggest that FKBP8 plays a critical role in the viral life cycle, particularly during the virus RNA replication period. The investigation of FKBP8 protein functions may be beneficial for developing new strategies to treat CSFV infection.
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Affiliation(s)
- Helin Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Chengcheng Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Hongjie Cui
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Kangkang Guo
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Fang Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Tianyue Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Wulong Liang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Qizhuang Lv
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China
| | - Yanming Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, People's Republic of China.
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13
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Saita S, Shirane M, Ishitani T, Shimizu N, Nakayama KI. Role of the ANKMY2-FKBP38 axis in regulation of the Sonic hedgehog (Shh) signaling pathway. J Biol Chem 2014; 289:25639-54. [PMID: 25077969 DOI: 10.1074/jbc.m114.558635] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Sonic hedgehog (Shh) is a secreted morphogen that controls the patterning and growth of various tissues in the developing vertebrate embryo, including the central nervous system. Ablation of the FK506-binding protein 38 (FKBP38) gene results in activation of the Shh signaling pathway in mouse embryos, but the molecular mechanism by which FKBP38 suppresses Shh signaling has remained unclear. With the use of a proteomics approach, we have now identified ANKMY2, a protein with three ankyrin repeats and a MYND (myeloid, Nervy, and DEAF-1)-type Zn(2+) finger domain, as a molecule that interacts with FKBP38. Co-immunoprecipitation analysis confirmed that endogenous FKBP38 and ANKMY2 interact in the mouse brain. Depletion or overexpression of ANKMY2 resulted in down- and up-regulation of Shh signaling, respectively, in mouse embryonic fibroblasts. Furthermore, combined depletion of both FKBP38 and ANKMY2 attenuated Shh signaling in these cells, suggesting that ANKMY2 acts downstream of FKBP38 to activate the Shh signaling pathway. Targeting of the zebrafish ortholog of mouse Ankmy2 (ankmy2a) in fish embryos with an antisense morpholino oligonucleotide conferred a phenotype reflecting loss of function of the Shh pathway, suggesting that the regulation of Shh signaling by ANKMY2 is conserved between mammals and fish. Our findings thus indicate that the FKBP38-ANKMY2 axis plays a key role in regulation of Shh signaling in vivo.
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Affiliation(s)
| | | | - Tohru Ishitani
- Division of Cell Regulation Systems, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
| | - Nobuyuki Shimizu
- Division of Cell Regulation Systems, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
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14
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Zheng X, Hao XY, Chen YH, Zhang X, Yang JF, Wang ZG, Liu DJ. Molecular Characterization and Tissue-specific Expression of a Novel FKBP38 Gene in the Cashmere Goat (Capra hircus). ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 25:758-63. [PMID: 25049623 PMCID: PMC4093086 DOI: 10.5713/ajas.2011.11398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 01/24/2012] [Accepted: 12/29/2011] [Indexed: 12/01/2022]
Abstract
As a member of a subclass of immunophilins, it is controversial that FKBP38 acts an upstream regulator of mTOR signaling pathway, which control the process of cell-growth, proliferation and differentiation. In order to explore the relationship between FKBP38 and mTOR in the Cashmere goat (Capra hircus) cells, a full-length cDNA was cloned (GenBank accession number JF714970) and expression pattern was analyzed. The cloned FKBP38 gene is 1,248 bp in length, containing an open reading frame (ORF) from nucleotide 13 to 1,248 which encodes 411 amino acids, and 12 nucleotides in front of the initiation codon. The full cDNA sequence shares 98% identity with cattle, 94% with horse and 90% with human. The putative amino acid sequence shows the higher homology which is 98%, 97% and 94%, correspondingly. The bioinformatics analysis showed that FKBP38 contained a FKBP_C domain, two TPR domains and a TM domain. Psite analysis suggested that the ORF encoding protein contained a leucine-zipper pattern and a Prenyl group binding site (CAAX box). Tissue-specific expression analysis was performed by semi-quantitative RT-PCR and showed that the FKBP38 expression was detected in all the tested tissues and the highest level of mRNA accumulation was detected in testis, suggesting that FKBP38 plays an important role in goat cells.
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Affiliation(s)
- X Zheng
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China
| | - X Y Hao
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China ; TEDA School of Biological Sciences and Biotechnology, Nankai University, 23HongDa Street, Tianjin 300457, China
| | - Y H Chen
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China
| | - X Zhang
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China
| | - J F Yang
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China
| | - Z G Wang
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China
| | - D J Liu
- College of Life Science, Inner Mongolia University, The Key Laboratory of Mammal Reproductive Biology and Biotechnology, Ministry of Education, Hohhot 010021, China
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15
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Galat A. Functional diversity and pharmacological profiles of the FKBPs and their complexes with small natural ligands. Cell Mol Life Sci 2013; 70:3243-75. [PMID: 23224428 PMCID: PMC11113493 DOI: 10.1007/s00018-012-1206-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 10/24/2012] [Accepted: 10/25/2012] [Indexed: 12/25/2022]
Abstract
From 5 to 12 FK506-binding proteins (FKBPs) are encoded in the genomes of disparate marine organisms, which appeared at the dawn of evolutionary events giving rise to primordial multicellular organisms with elaborated internal body plan. Fifteen FKBPs, several FKBP-like proteins and some splicing variants of them are expressed in humans. Human FKBP12 and some of its paralogues bind to different macrocyclic antibiotics such as FK506 or rapamycin and their derivatives. FKBP12/(macrocyclic antibiotic) complexes induce diverse pharmacological activities such as immunosuppression in humans, anticancerous actions and as sustainers of quiescence in certain organisms. Since the FKBPs bind to various assemblies of proteins and other intracellular components, their complexes with the immunosuppressive drugs may differentially perturb miscellaneous cellular functions. Sequence-structure relationships and pharmacological profiles of diverse FKBPs and their involvement in crucial intracellular signalization pathways and modulation of cryptic intercellular communication networks were discussed.
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Affiliation(s)
- Andrzej Galat
- Commissariat à l'Energie Atomique, Direction des Sciences du Vivant, Institut de Biologie et de Technologies de Saclay, Service d'Ingénierie Moléculaire des Protéines, Bat. 152, 91191, Gif-sur-Yvette Cedex, France.
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16
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Saita S, Shirane M, Nakayama KI. Selective escape of proteins from the mitochondria during mitophagy. Nat Commun 2013; 4:1410. [PMID: 23361001 DOI: 10.1038/ncomms2400] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 12/17/2012] [Indexed: 12/22/2022] Open
Abstract
Mitophagy refers to the degradation of mitochondria by the autophagy system that is regulated by Parkin and PINK1, mutations in the genes for which have been linked to Parkinson's disease. Here we show that certain mitochondrial outer membrane proteins, including FKBP38 and Bcl-2, translocate from the mitochondria to the endoplasmic reticulum (ER) during mitophagy, thereby escaping degradation by autophagosomes. This translocation depends on the ubiquitylation activity of Parkin and on microtubule polymerization. Photoconversion analysis confirmed that FKBP38 detected at the ER during mitophagy indeed represents preexisting protein transported from the mitochondria. The escape of FKBP38 and Bcl-2 from the mitochondria is determined by the number of basic amino acids in their COOH-terminal signal sequences. Furthermore, the translocation of FKBP38 is essential for the suppression of apoptosis during mitophagy. Our results thus show that not all mitochondrial proteins are degraded during mitophagy, with some proteins being evacuated to the ER to prevent unwanted apoptosis.
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Affiliation(s)
- Shotaro Saita
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
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17
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Vadász I, Weiss CH, Sznajder JI. Ubiquitination and proteolysis in acute lung injury. Chest 2012; 141:763-771. [PMID: 22396561 DOI: 10.1378/chest.11-1660] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Ubiquitination is a posttranslational modification that regulates a variety of cellular functions depending on timing, subcellular localization, and type of tagging, as well as modulators of ubiquitin binding leading to proteasomal or lysosomal degradation or nonproteolytic modifications. Ubiquitination plays an important role in the pathogenesis of acute lung injury (ALI) and other lung diseases with pathologies secondary to inflammation, mechanical ventilation, and decreased physical mobility. Particularly, ubiquitination has been shown to affect alveolar epithelial barrier function and alveolar edema clearance by targeting the Na,K-ATPase and epithelial Na(+) channels upon lung injury. Notably, the proteasomal system also exhibits distinct functions in the extracellular space, which may contribute to the pathogenesis of ALI and other pulmonary diseases. Better understanding of these mechanisms may ultimately lead to novel therapeutic modalities by targeting elements of the ubiquitination pathway.
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Affiliation(s)
- István Vadász
- Department of Internal Medicine, University of Giessen Lung Center, Justus Liebig University, Giessen, Germany.
| | - Curtis H Weiss
- Division of Pulmonary and Critical Care Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Jacob I Sznajder
- Division of Pulmonary and Critical Care Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL
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18
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Banasavadi-Siddegowda YK, Mai J, Fan Y, Bhattacharya S, Giovannucci DR, Sanchez ER, Fischer G, Wang X. FKBP38 peptidylprolyl isomerase promotes the folding of cystic fibrosis transmembrane conductance regulator in the endoplasmic reticulum. J Biol Chem 2011; 286:43071-80. [PMID: 22030396 DOI: 10.1074/jbc.m111.269993] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
FK506-binding protein 38 (FKBP38), a membrane-anchored, tetratricopeptide repeat (TPR)-containing immunophilin, associates with nascent plasma membrane ion channels in the endoplasmic reticulum (ER). It promotes the maturation of the human ether-à-go-go-related gene (HERG) potassium channel and maintains the steady state level of the cystic fibrosis transmembrane conductance regulator (CFTR), but the underlying mechanisms remain unclear. Using a combination of steady state and pulse-chase analyses, we show that FKBP38 knockdown increases protein synthesis but inhibits the post-translational folding of CFTR, leading to reduced steady state levels of CFTR in the ER, decreased processing, and impaired cell surface functional expression in Calu-3 human airway epithelial cells. The membrane anchorage of FKBP38 is necessary for the inhibition of protein synthesis but not for CFTR post-translational folding. In contrast, the peptidylprolyl cis/trans isomerase active site is utilized to promote CFTR post-translational folding but is not important for regulation of protein synthesis. Uncoupling FKBP38 from Hsp90 by substituting a conserved lysine in the TPR domain modestly enhances CFTR maturation and further reduces its synthesis. Removing the N-terminal glutamate-rich domain (ERD) slightly enhances CFTR synthesis but reduces its maturation, suggesting that the ERD contributes to FKBP38 biological activities. Our data support a dual role for FKBP38 in regulating CFTR synthesis and post-translational folding. In contrast to earlier prediction but consistent with in vitro enzymological studies, FKBP38 peptidylprolyl cis/trans isomerase plays an important role in membrane protein biogenesis on the cytoplasmic side of the ER membrane, whose activity is negatively regulated by Hsp90 through the TPR domain.
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19
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Abstract
The omnipresent ubiquitin–proteasome system (UPS) is an ATP-dependent enzymatic machinery that targets substrate proteins for degradation by the 26S proteasome by tagging them with an isopeptide chain composed of covalently linked molecules of ubiquitin, a small chaperone protein. The current knowledge of UPS involvement in the process of sperm penetration through vitelline coat (VC) during human and animal fertilization is reviewed in this study, with attention also being given to sperm capacitation and acrosome reaction/exocytosis. In ascidians, spermatozoa release ubiquitin-activating and conjugating enzymes, proteasomes, and unconjugated ubiquitin to first ubiquitinate and then degrade the sperm receptor on the VC; in echinoderms and mammals, the VC (zona pellucida/ZP in mammals) is ubiquitinated during oogenesis and the sperm receptor degraded during fertilization. Various proteasomal subunits and associated enzymes have been detected in spermatozoa and localized to sperm acrosome and other sperm structures. By using specific fluorometric substrates, proteasome-specific proteolytic and deubiquitinating activities can be measured in live, intact spermatozoa and in sperm protein extracts. The requirement of proteasomal proteolysis during fertilization has been documented by the application of various proteasome-specific inhibitors and antibodies. A similar effect was achieved by depletion of sperm-surface ATP. Degradation of VC/ZP-associated sperm receptor proteins by sperm-borne proteasomes has been demonstrated in ascidians and sea urchins. On the applied side, polyspermy has been ameliorated by modulating sperm-associated deubiquitinating enzymes. Diagnostic and therapeutic applications could emerge in human reproductive medicine. Altogether, the studies on sperm proteasome indicate that animal fertilization is controlled in part by a unique, gamete associated, extracellular UPS.
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20
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Yoshii SR, Kishi C, Ishihara N, Mizushima N. Parkin mediates proteasome-dependent protein degradation and rupture of the outer mitochondrial membrane. J Biol Chem 2011; 286:19630-40. [PMID: 21454557 PMCID: PMC3103342 DOI: 10.1074/jbc.m110.209338] [Citation(s) in RCA: 475] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 03/15/2011] [Indexed: 01/15/2023] Open
Abstract
Upon mitochondrial depolarization, Parkin, a Parkinson disease-related E3 ubiquitin ligase, translocates from the cytosol to mitochondria and promotes their degradation by mitophagy, a selective type of autophagy. Here, we report that in addition to mitophagy, Parkin mediates proteasome-dependent degradation of outer membrane proteins such as Tom20, Tom40, Tom70, and Omp25 of depolarized mitochondria. By contrast, degradation of the inner membrane and matrix proteins largely depends on mitophagy. Furthermore, Parkin induces rupture of the outer membrane of depolarized mitochondria, which also depends on proteasomal activity. Upon induction of mitochondrial depolarization, proteasomes are recruited to mitochondria in the perinuclear region. Neither proteasome-dependent degradation of outer membrane proteins nor outer membrane rupture is required for mitophagy. These results suggest that Parkin regulates degradation of outer and inner mitochondrial membrane proteins differently through proteasome- and mitophagy-dependent pathways.
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Affiliation(s)
- Saori R. Yoshii
- From the Department of Physiology and Cell Biology, Tokyo Medical and Dental University, Tokyo 113-8519 and
| | - Chieko Kishi
- From the Department of Physiology and Cell Biology, Tokyo Medical and Dental University, Tokyo 113-8519 and
| | - Naotada Ishihara
- From the Department of Physiology and Cell Biology, Tokyo Medical and Dental University, Tokyo 113-8519 and
- the Department of Protein Biochemistry, Institute of Life Science, Kurume University, Kurume 839-0864, Japan
| | - Noboru Mizushima
- From the Department of Physiology and Cell Biology, Tokyo Medical and Dental University, Tokyo 113-8519 and
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21
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Li M, Jayandharan GR, Li B, Ling C, Ma W, Srivastava A, Zhong L. High-efficiency transduction of fibroblasts and mesenchymal stem cells by tyrosine-mutant AAV2 vectors for their potential use in cellular therapy. Hum Gene Ther 2010; 21:1527-43. [PMID: 20507237 DOI: 10.1089/hum.2010.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Adeno-associated virus 2 (AAV2) vectors transduce fibroblasts and mesenchymal stem cells (MSCs) inefficiently, which limits their potential widespread applicability in combinatorial gene and cell therapy. We have reported that AAV2 vectors fail to traffic efficiently to the nucleus in murine fibroblasts. We have also reported that site-directed mutagenesis of surface-exposed tyrosine residues on viral capsids leads to improved intracellular trafficking of the mutant vectors, and the transduction efficiency of the single tyrosine-mutant vectors is ∼10-fold higher in human cells. In the current studies, we evaluated the transduction efficiency of single as well as multiple tyrosine-mutant AAV2 vectors in murine fibroblasts. Our results indicate that the Y444F mutant vectors transduce these cells most efficiently among the seven single-mutant vectors, with >30-fold increase in transgene expression compared with the wild-type vectors. When the Y444F mutation is combined with additional mutations (Y500F and Y730F), the transduction efficiency of the triple-mutant vectors is increased by ∼130-fold and the viral intracellular trafficking is also significant improved. Similarly, the triple-mutant vectors are capable of transducing up to 80-90% of bone marrow-derived primary murine as well as human MSCs. Thus, high-efficiency transduction of fibroblasts with reprogramming genes to generate induced pluripotent stem cells, and the MSCs for delivering therapeutic genes, should now be feasible with the tyrosine-mutant AAV vectors.
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Affiliation(s)
- Mengxin Li
- Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605, USA
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22
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Peng L, Liang D, Tong W, Li J, Yuan Z. Hepatitis C virus NS5A activates the mammalian target of rapamycin (mTOR) pathway, contributing to cell survival by disrupting the interaction between FK506-binding protein 38 (FKBP38) and mTOR. J Biol Chem 2010; 285:20870-81. [PMID: 20439463 PMCID: PMC2898342 DOI: 10.1074/jbc.m110.112045] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Revised: 04/25/2010] [Indexed: 01/16/2023] Open
Abstract
Hepatitis C virus (HCV) often establishes a persistent infection that most likely involves a complex host-virus interplay. We previously reported that the HCV nonstructural protein 5A (NS5A) bound to cellular protein FKBP38 and resulted in apoptosis suppression in human hepatoma cell line Huh7. In the present research we further found that NS5A increased phosphorylation levels of two mTOR-targeted substrates, S6K1 and 4EBP1, in Huh7 in the absence of serum. mTOR inhibitor rapamycin or NS5A knockdown blocked S6K1 and 4EBP1 phosphorylation increase in NS5A-Huh7 and HCV replicon cells, suggesting that NS5A specifically regulated mTOR activation. Overexpression of NS5A and FKBP38 mutants or FKBP38 knockdown revealed this mTOR activation was dependent on NS5A-FKBP38 interaction. Phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 treatment in NS5A-Huh7 showed that the mTOR activation was independent of PI3K. Moreover, NS5A suppressed caspase 3 and poly(ADP-ribose) polymerase activation, which was abolished by NS5A knockdown or rapamycin, indicating NS5A inhibited apoptosis specifically through the mTOR pathway. Further analyses suggested that apoptotic inhibition exerted by NS5A via mTOR also required NS5A-FKBP38 interaction. Glutathione S-transferase pulldown and co-immunoprecipitation showed that NS5A disrupted the mTOR-FKBP38 association. Additionally, NS5A or FKBP38 mutants recovered the mTOR-FKBP38 interaction; this indicated that the impairment of mTOR-FKBP38 association was dependent on NS5A-FKBP38 binding. Collectively, our data demonstrate that HCV NS5A activates the mTOR pathway to inhibit apoptosis through impairing the interaction between mTOR and FKBP38, which may represent a pivotal mechanism for HCV persistence and pathogenesis.
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Affiliation(s)
- Lu Peng
- From the Key Laboratory of Medical Molecular Virology, Shanghai Medical College, and
| | - Dongyu Liang
- From the Key Laboratory of Medical Molecular Virology, Shanghai Medical College, and
| | - Wenyan Tong
- From the Key Laboratory of Medical Molecular Virology, Shanghai Medical College, and
| | - Jianhua Li
- From the Key Laboratory of Medical Molecular Virology, Shanghai Medical College, and
| | - Zhenghong Yuan
- From the Key Laboratory of Medical Molecular Virology, Shanghai Medical College, and
- Institutes of Medical Microbiology and Biomedical Sciences, Fudan University, Shanghai 200032, China
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23
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Wiles AM, Doderer M, Ruan J, Gu TT, Ravi D, Blackman B, Bishop AJR. Building and analyzing protein interactome networks by cross-species comparisons. BMC SYSTEMS BIOLOGY 2010; 4:36. [PMID: 20353594 PMCID: PMC2859380 DOI: 10.1186/1752-0509-4-36] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Accepted: 03/30/2010] [Indexed: 11/10/2022]
Abstract
Background A genomic catalogue of protein-protein interactions is a rich source of information, particularly for exploring the relationships between proteins. Numerous systems-wide and small-scale experiments have been conducted to identify interactions; however, our knowledge of all interactions for any one species is incomplete, and alternative means to expand these network maps is needed. We therefore took a comparative biology approach to predict protein-protein interactions across five species (human, mouse, fly, worm, and yeast) and developed InterologFinder for research biologists to easily navigate this data. We also developed a confidence score for interactions based on available experimental evidence and conservation across species. Results The connectivity of the resultant networks was determined to have scale-free distribution, small-world properties, and increased local modularity, indicating that the added interactions do not disrupt our current understanding of protein network structures. We show examples of how these improved interactomes can be used to analyze a genome-scale dataset (RNAi screen) and to assign new function to proteins. Predicted interactions within this dataset were tested by co-immunoprecipitation, resulting in a high rate of validation, suggesting the high quality of networks produced. Conclusions Protein-protein interactions were predicted in five species, based on orthology. An InteroScore, a score accounting for homology, number of orthologues with evidence of interactions, and number of unique observations of interactions, is given to each known and predicted interaction. Our website http://www.interologfinder.org provides research biologists intuitive access to this data.
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Affiliation(s)
- Amy M Wiles
- Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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24
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Choi BH, Feng L, Yoon HS. FKBP38 protects Bcl-2 from caspase-dependent degradation. J Biol Chem 2010; 285:9770-9779. [PMID: 20139069 DOI: 10.1074/jbc.m109.032466] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The cellular processes that regulate Bcl-2 at the posttranslational levels are as important as those that regulate bcl-2 synthesis. Previously we demonstrated that the suppression of FK506-binding protein 38 (FKBP38) contributes to the instability of Bcl-2 or leaves Bcl-2 unprotected from degradation in an unknown mechanism. Here, we studied the underlying molecular mechanism mediating this process. We first showed that Bcl-2 binding-defective mutants of FKBP38 fail to accumulate Bcl-2 protein. We demonstrated that the FKBP38-mediated Bcl-2 stability is specific as the levels of other anti-apoptotic proteins such as Bcl-X(L) and Mcl-1 remained unaffected. FKBP38 enhanced the Bcl-2 stability under the blockade of de novo protein synthesis, indicating it is posttranslational. We showed that the overexpression of FKBP38 attenuates reduction rate of Bcl-2, thus resulting in an increment of the intracellular Bcl-2 level, contributing to the resistance of apoptotic cell death induced by the treatment of kinetin riboside, an anticancer drug. Caspase inhibitors markedly induced the accumulation of Bcl-2. In caspase-3-activated cells, the knockdown of endogenous FKBP38 by small interfering RNA resulted in Bcl-2 down-regulation as well, which was significantly recovered by the treatment with caspase inhibitors or overexpression of FKBP38. Finally we presented that the Bcl-2 cleavage by caspase-3 is blocked when Bcl-2 binds to FKBP38 through the flexible loop. Taken together, these results suggest that FKBP38 is a key player in regulating the function of Bcl-2 by antagonizing caspase-dependent degradation through the direct interaction with the flexible loop domain of Bcl-2, which contains the caspase cleavage site.
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Affiliation(s)
- Bo-Hwa Choi
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Lin Feng
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Ho Sup Yoon
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
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25
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Azzu V, Brand MD. Degradation of an intramitochondrial protein by the cytosolic proteasome. J Cell Sci 2010; 123:578-85. [PMID: 20103532 DOI: 10.1242/jcs.060004] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mitochondrial uncoupling protein 2 (UCP2) is implicated in a wide range of pathophysiological processes, including immunity and diabetes mellitus, but its rapid degradation remains uncharacterized. Using pharmacological proteasome inhibitors, immunoprecipitation, dominant negative ubiquitin mutants, [corrected] cellular fractionation and siRNA techniques, we demonstrate the involvement of the ubiquitin-proteasome system in the rapid degradation of UCP2. Importantly, we resolve the issue of whether intramitochondrial proteins can be degraded by the cytosolic proteasome by reconstituting a cell-free system that shows rapid proteasome-inhibitor-sensitive UCP2 degradation in isolated, energised mitochondria presented with an ATP regenerating system, ubiquitin and 26S proteasome fractions. These observations provide the first demonstration that a mitochondrial inner membrane protein is degraded by the cytosolic ubiquitin-proteasome system.
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Affiliation(s)
- Vian Azzu
- MRC Mitochondrial Biology Unit, Hills Road, Cambridge CB2 0XY, UK
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26
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Barth S, Edlich F, Berchner-Pfannschmidt U, Gneuss S, Jahreis G, Hasgall PA, Fandrey J, Wenger RH, Camenisch G. Hypoxia-inducible factor prolyl-4-hydroxylase PHD2 protein abundance depends on integral membrane anchoring of FKBP38. J Biol Chem 2009; 284:23046-58. [PMID: 19546213 DOI: 10.1074/jbc.m109.032631] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prolyl-4-hydroxylase domain (PHD) proteins are 2-oxoglutarate and dioxygen-dependent enzymes that mediate the rapid destruction of hypoxia-inducible factor alpha subunits. Whereas PHD1 and PHD3 proteolysis has been shown to be regulated by Siah2 ubiquitin E3 ligase-mediated polyubiquitylation and proteasomal destruction, protein regulation of the main oxygen sensor responsible for hypoxia-inducible factor alpha regulation, PHD2, remained unknown. We recently reported that the FK506-binding protein (FKBP) 38 specifically interacts with PHD2 and determines PHD2 protein stability in a peptidyl-prolyl cis-trans isomerase-independent manner. Using peptide array binding assays, fluorescence spectroscopy, and fluorescence resonance energy transfer analysis, we defined a minimal linear glutamate-rich PHD2 binding domain in the N-terminal part of FKBP38 and showed that this domain forms a high affinity complex with PHD2. Vice versa, PHD2 interacted with a non-linear N-terminal motif containing the MYND (myeloid, Nervy, and DEAF-1)-type Zn(2+) finger domain with FKBP38. Biochemical fractionation and immunofluorescence analysis demonstrated that PHD2 subcellular localization overlapped with FKBP38 in the endoplasmic reticulum and mitochondria. An additional fraction of PHD2 was found in the cytoplasm. In cellulo PHD2/FKBP38 association, as well as regulation of PHD2 protein abundance by FKBP38, is dependent on membrane- anchored FKBP38 localization mediated by the C-terminal transmembrane domain. Mechanistically our data indicate that PHD2 protein stability is regulated by a ubiquitin-independent proteasomal pathway involving FKBP38 as adaptor protein that mediates proteasomal interaction. We hypothesize that FKBP38-bound PHD2 is constantly degraded whereas cytosolic PHD2 is stable and able to function as an active prolyl-4-hydroxylase.
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Affiliation(s)
- Sandra Barth
- Institute of Physiology and Zürich Center for Integrative Human Physiology (ZIHP), University of Zürich, CH-8057 Zürich, Switzerland
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27
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Brush JM, Kim K, Sayre JW, McBride WH, Iwamoto KS. Imaging of radiation effects on cellular 26S proteasome function in situ. Int J Radiat Biol 2009; 85:483-94. [PMID: 19401903 DOI: 10.1080/09553000902883794] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE The classical radiobiological paradigm is that DNA is the target for cell damage caused by ionising radiation. However, evidence is accumulating that other constituents, such as the membrane, organelles, and proteins, are also important targets. We have shown that the isolated 26S proteasome is one such target and here we wish to substantiate it within the cell, in situ. MATERIALS AND METHODS We used confocal microscopy to quantitatively detect and subcellularly localise radiation-induced 26S proteasome inhibition in cells expressing an ornithine decarboxylase degron that targets a fused Zoanthus species green (ZsGreen) fluorescent protein reporter specifically to the 26S proteasome. RESULTS Exposure of cells to a range of radiation doses, even as low as 0.05 Gy inhibited 26S activity within minutes. Initially, punctate nuclear ZsGreen fluorescence was observed that became cytoplasmic after seven hours -- a pattern distinct from the diffuse homogeneous fluorescence of cells incubated in the conventional proteasome inhibitor MG-132. CONCLUSIONS Our study clearly indicates that the 26S proteasome is a radiation target with physiological consequences and introduces a new perspective in mechanistic investigations of cellular responses to stresses.
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Affiliation(s)
- James M Brush
- Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-1714, USA
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28
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Saita S, Shirane M, Natume T, Iemura SI, Nakayama KI. Promotion of neurite extension by protrudin requires its interaction with vesicle-associated membrane protein-associated protein. J Biol Chem 2009; 284:13766-13777. [PMID: 19289470 DOI: 10.1074/jbc.m807938200] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Protrudin is a protein that contains a Rab11-binding domain and a FYVE (lipid-binding) domain and that functions to promote neurite formation through interaction with the GDP-bound form of Rab11. Protrudin also contains a short sequence motif designated FFAT (two phenylalanines in an acidic tract), which in other proteins has been shown to mediate binding to vesicle-associated membrane protein-associated protein (VAP). We now show that protrudin associates and colocalizes with VAP-A, an isoform of VAP expressed in the endoplasmic reticulum. Both the interaction between protrudin and VAP-A as well as the induction of process formation by protrudin were markedly inhibited by mutation of the FFAT motif. Furthermore, depletion of VAP-A by RNA interference resulted in mislocalization of protrudin as well as in inhibition of neurite outgrowth induced by nerve growth factor in rat pheochromocytoma PC12 cells. These defects resulting from depletion of endogenous rat VAP-A in PC12 cells were corrected by forced expression of (RNA interference-resistant) human VAP-A but not by VAP-A mutants that have lost the ability to interact with protrudin. These results suggest that VAP-A is an important regulator both of the subcellular localization of protrudin and of its ability to stimulate neurite outgrowth.
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Affiliation(s)
- Shotaro Saita
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan; CREST, Japan Science and Technology Corporation, Kawaguchi, Saitama 332-0012, Japan
| | - Michiko Shirane
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan; CREST, Japan Science and Technology Corporation, Kawaguchi, Saitama 332-0012, Japan
| | - Tohru Natume
- National Institutes of Advanced Industrial Science, Kohtoh-ku, Tokyo 135-0064, Japan
| | - Shun-Ichiro Iemura
- National Institutes of Advanced Industrial Science, Kohtoh-ku, Tokyo 135-0064, Japan
| | - Keiichi I Nakayama
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan; CREST, Japan Science and Technology Corporation, Kawaguchi, Saitama 332-0012, Japan.
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29
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Patterson VL, Damrau C, Paudyal A, Reeve B, Grimes DT, Stewart ME, Williams DJ, Siggers P, Greenfield A, Murdoch JN. Mouse hitchhiker mutants have spina bifida, dorso-ventral patterning defects and polydactyly: identification of Tulp3 as a novel negative regulator of the Sonic hedgehog pathway. Hum Mol Genet 2009; 18:1719-39. [PMID: 19223390 PMCID: PMC2671985 DOI: 10.1093/hmg/ddp075] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The mammalian Sonic hedgehog (Shh) signalling pathway is essential for embryonic development and the patterning of multiple organs. Disruption or activation of Shh signalling leads to multiple birth defects, including holoprosencephaly, neural tube defects and polydactyly, and in adults results in tumours of the skin or central nervous system. Genetic approaches with model organisms continue to identify novel components of the pathway, including key molecules that function as positive or negative regulators of Shh signalling. Data presented here define Tulp3 as a novel negative regulator of the Shh pathway. We have identified a new mouse mutant that is a strongly hypomorphic allele of Tulp3 and which exhibits expansion of ventral markers in the caudal spinal cord, as well as neural tube defects and preaxial polydactyly, consistent with increased Shh signalling. We demonstrate that Tulp3 acts genetically downstream of Shh and Smoothened (Smo) in neural tube patterning and exhibits a genetic interaction with Gli3 in limb development. We show that Tulp3 does not appear to alter expression or processing of Gli3, and we demonstrate that transcriptional regulation of other negative regulators (Rab23, Fkbp8, Thm1, Sufu and PKA) is not affected. We discuss the possible mechanism of action of Tulp3 in Shh-mediated signalling in light of these new data.
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Affiliation(s)
- Victoria L Patterson
- Mammalian Genetics Unit, MRC Harwell, Harwell Science and Innovation Campus, Oxon, UK
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