1
|
Li X, Jiao K, Liu C, Li X, Wang S, Tao Y, Cheng Y, Zhou X, Wei X, Li M. Bibliometric analysis of the inflammation expression after spinal cord injury: current research status and emerging frontiers. Spinal Cord 2024:10.1038/s41393-024-01038-w. [PMID: 39363043 DOI: 10.1038/s41393-024-01038-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Revised: 09/18/2024] [Accepted: 09/24/2024] [Indexed: 10/05/2024]
Abstract
STUDY DESIGN Bibliometric analysis. OBJECTIVE To analyze literature on inflammatory expression following spinal cord injury, highlighting development trends, current research status, and potential emerging frontiers. SETTING Not applicable. METHODS Articles were retrieved using terms related to spinal cord injury and inflammatory responses from the Web of Science Core Collection, covering January 1, 1980, to May 23, 2024. Tools like CiteSpace and VOSviewer assessed the research landscape, evaluating core authors, journals, and contributing countries. Keyword co-occurrence analyses identified research trends. RESULTS A total of 2504 articles were retrieved, showing a consistent increase in publications. The Journal of Neurotrauma had the highest publication volume and influence. The most prolific author was Cuzzocrea S, with Popovich PG having the highest H-index. China led in the number of publications, followed closely by the United States, which had the highest impact and extensive international collaboration. Research mainly focused on nerve function recovery, glial scar formation, and oxidative stress. Future research is expected to investigate cellular autophagy, vesicular transport, and related signaling pathways. CONCLUSION The growing interest in inflammation caused by spinal cord injury is evident, with current research focusing on oxidative stress, glial scar, and neurological recovery. Future directions include exploring autophagy and extracellular vesicles for new therapies. Interdisciplinary research and extensive clinical trials are essential for validating new treatments. Biomarker discovery is crucial for diagnosis and monitoring, while understanding autophagy and signaling pathways is vital for drug development. Global cooperation is needed to accelerate the application of scientific findings, improving spinal cord injury treatment.
Collapse
Affiliation(s)
- Xiaoyu Li
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Kun Jiao
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Chen Liu
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Xiongfei Li
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Shanhe Wang
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Ye Tao
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Yajun Cheng
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China
| | - Xiaoyi Zhou
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China.
| | - Xianzhao Wei
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China.
| | - Ming Li
- Department of Orthopedics, Shanghai Changhai Hospital, Shanghai, China.
| |
Collapse
|
2
|
Wang M, Wang J, Guo Y. Reconstitution of Vesicle Budding from the TGN and Immunoisolation of Vesicles Enriched with a Specific Cargo Client. Methods Mol Biol 2022; 2557:289-302. [PMID: 36512223 DOI: 10.1007/978-1-0716-2639-9_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The trans-Golgi network (TGN) is an important cargo sorting station in the secretory pathway. To reveal insights into protein sorting at the TGN, it is important to develop an assay to quantify the efficiency of cargo capture. Here, we describe an experimental approach to reconstitute the packaging of cargo proteins into vesicles at the TGN in vitro. We also describe an experimental approach to immunoisolate vesicles enriched with a specific transmembrane cargo client from the in vitro vesicle formation assay. These assays provide robust tools to directly measure the enrichment of cargo proteins into TGN-derived vesicles and to reveal novel factors that regulate TGN export process.
Collapse
Affiliation(s)
- Mo Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Jinhui Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yusong Guo
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China. .,Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen, China. .,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.
| |
Collapse
|
3
|
TMAO to the rescue of pathogenic protein variants. Biochim Biophys Acta Gen Subj 2022; 1866:130214. [PMID: 35902028 DOI: 10.1016/j.bbagen.2022.130214] [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: 02/03/2022] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 11/22/2022]
Abstract
Trimethylamine N-oxide (TMAO) is a chemical chaperone found in various organisms including humans. Various studies unveiled that it is an excellent protein-stabilizing agent, and induces folding of unstructured proteins. It is also well established that it can counteract the deleterious effects of urea, salt, and hydrostatic pressure on macromolecular integrity. There is also existence of large body of data regarding its ability to restore functional deficiency of various mutant proteins or pathogenic variants by correcting misfolding defects and inhibiting the formation of high-order toxic protein oligomers. Since an important class of human disease called "protein conformational disorders" is due to protein misfolding and/or formation of high-order oligomers, TMAO stands as a promising molecule for the therapeutic intervention of such diseases. The present review has been designed to gather a comprehensive knowledge of the TMAO's effect on the functional restoration of various mutants, identify its shortcomings and explore its potentiality as a lead molecule. Future prospects have also been suitably incorporated.
Collapse
|
4
|
Suga K, Yamamoto-Hijikata S, Terao Y, Akagawa K, Ushimaru M. Golgi stress induces upregulation of the ER-Golgi SNARE Syntaxin-5, altered βAPP processing, and Caspase-3-dependent apoptosis in NG108-15 cells. Mol Cell Neurosci 2022; 121:103754. [PMID: 35842170 DOI: 10.1016/j.mcn.2022.103754] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 05/29/2022] [Accepted: 07/07/2022] [Indexed: 01/06/2023] Open
Abstract
The involvement of secretory pathways and Golgi dysfunction in neuronal cells during Alzheimer's disease progression is poorly understood. Our previous overexpression and knockdown studies revealed that the intracellular protein level of Syntaxin-5, an endoplasmic reticulum-Golgi soluble N-ethylmaleimide-sensitive factor-attachment protein receptor (SNARE), modulates beta-amyloid precursor protein processing in neuronal cells. We recently showed that changes in endogenous Syntaxin-5 protein expression occur under stress induction. Syntaxin-5 was upregulated by endoplasmic reticulum stress but was degraded by Caspase-3 during apoptosis in neuronal cells. In addition, we showed that sustained endoplasmic reticulum stress promotes Caspase-3-dependent apoptosis during the later phase of the endoplasmic reticulum stress response in NG108-15 cells. In this study, to elucidate the consequences of secretory pathway dysfunction in beta-amyloid precursor protein processing that lead to neuronal cell death, we examined the effect of various stresses on endoplasmic reticulum-Golgi SNARE expression and beta-amyloid precursor protein processing. By using compounds to disrupt Golgi function, we show that Golgi stress promotes upregulation of the endoplasmic reticulum-Golgi SNARE Syntaxin-5, and prolonged stress causes Caspase-3-dependent apoptosis. Golgi stress induced intracellular beta-amyloid precursor protein accumulation and a concomitant decrease in total amyloid-beta production. We also examined the protective effect of the chemical chaperone 4-phenylbutylate on changes in amyloid-beta production and the activation of Caspase-3 induced by endoplasmic reticulum and Golgi stress. The compound alleviated the increase in the amyloid-beta 1-42/amyloid-beta 1-40 ratio induced by endoplasmic reticulum and Golgi stress. Furthermore, 4-phenylbutylate could rescue Caspase-3-dependent apoptosis induced by prolonged organelle stress. These results suggest that organelle stress originating from the endoplasmic reticulum and Golgi has a substantial impact on the amyloidogenic processing of beta-amyloid precursor protein and Caspase-3-dependent apoptosis, leading to neuronal cell death.
Collapse
Affiliation(s)
- Kei Suga
- Department of Chemistry, Kyorin University, Faculty of Medicine, Mitaka, Tokyo 181-8611, Japan; Department of Medical Physiology, Kyorin University, Faculty of Medicine, Mitaka, Tokyo 181-8611, Japan.
| | | | - Yasuo Terao
- Department of Medical Physiology, Kyorin University, Faculty of Medicine, Mitaka, Tokyo 181-8611, Japan
| | - Kimio Akagawa
- Department of Medical Physiology, Kyorin University, Faculty of Medicine, Mitaka, Tokyo 181-8611, Japan
| | - Makoto Ushimaru
- Department of Chemistry, Kyorin University, Faculty of Medicine, Mitaka, Tokyo 181-8611, Japan
| |
Collapse
|
5
|
Hasegawa J, Uchida Y, Mukai K, Lee S, Matsudaira T, Taguchi T. A Role of Phosphatidylserine in the Function of Recycling Endosomes. Front Cell Dev Biol 2022; 9:783857. [PMID: 35004683 PMCID: PMC8740049 DOI: 10.3389/fcell.2021.783857] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 11/29/2021] [Indexed: 11/13/2022] Open
Abstract
Cells internalize proteins and lipids in the plasma membrane (PM) and solutes in the extracellular space by endocytosis. The removal of PM by endocytosis is constantly balanced by the replenishment of proteins and lipids to PM through recycling pathway. Recycling endosomes (REs) are specific subsets of endosomes. Besides the established role of REs in recycling pathway, recent studies have revealed unanticipated roles of REs in membrane traffic and cell signalling. In this review, we highlight these emerging issues, with a particular focus on phosphatidylserine (PS), a phospholipid that is highly enriched in the cytosolic leaflet of RE membranes. We also discuss the pathogenesis of Hermansky Pudlak syndrome type 2 (HPS2) that arises from mutations in the AP3B1 gene, from the point of view of dysregulated RE functions.
Collapse
Affiliation(s)
- Junya Hasegawa
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Yasunori Uchida
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Kojiro Mukai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Shoken Lee
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Tatsuyuki Matsudaira
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| | - Tomohiko Taguchi
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan
| |
Collapse
|
6
|
Zarbock KR, Han JH, Singh AP, Thomas SP, Bendlin BB, Denu JM, Yu JPJ, Rey FE, Ulland TK. Trimethylamine N-Oxide Reduces Neurite Density and Plaque Intensity in a Murine Model of Alzheimer's Disease. J Alzheimers Dis 2022; 90:585-597. [PMID: 36155509 PMCID: PMC9881463 DOI: 10.3233/jad-220413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common aging-associated neurodegenerative disease; nevertheless, the etiology and progression of the disease is still incompletely understood. We have previously shown that the microbially-derived metabolite trimethylamine N-oxide (TMAO) is elevated in the cerebrospinal fluid (CSF) of individuals with cognitive impairment due to AD and positively correlates with increases in CSF biomarkers for tangle, plaque, and neuronal pathology. OBJECTIVE We assessed the direct impact of TMAO on AD progression. METHODS To do so, transgenic 5XFAD mice were supplemented with TMAO for 12 weeks. Neurite density was assessed through quantitative brain microstructure imaging with neurite orientation dispersion and density imaging magnetic resonance imaging (MRI). Label-free, quantitative proteomics was performed on cortex lysates from TMAO-treated and untreated animals. Amyloid-β plaques, astrocytes, and microglia were assessed by fluorescent immunohistochemistry and synaptic protein expression was quantified via western blot. RESULTS Oral TMAO administration resulted in significantly reduced neurite density in several regions of the brain. Amyloid-β plaque mean intensity was reduced, while plaque count and size remained unaltered. Proteomics analysis revealed that TMAO treatment impacted the expression of 30 proteins (1.5-fold cut-off) in 5XFAD mice, including proteins known to influence neuronal health and amyloid-β precursor protein processing. TMAO treatment did not alter astrocyte and microglial response nor cortical synaptic protein expression. CONCLUSION These data suggest that elevated plasma TMAO impacts AD pathology via reductions in neurite density.
Collapse
Affiliation(s)
- Katie R. Zarbock
- University of Wisconsin-Madison, Department of Bacteriology
- University of Wisconsin-Madison, Department of Pathology and Laboratory Medicine
| | - Jessica H. Han
- University of Wisconsin-Madison, Department of Bacteriology
- University of Wisconsin-Madison, Department of Biomolecular Chemistry
| | - Ajay P. Singh
- University of Wisconsin-Madison, Department of Radiology, Division of Neuroradiology
| | - Sydney P. Thomas
- University of Wisconsin-Madison, Department of Biomolecular Chemistry
| | - Barbara B. Bendlin
- University of Wisconsin-Madison, Department of Medicine, Division of Geriatrics and Gerontology
- Wisconsin Alzheimer’s Disease Research Center
| | - John M. Denu
- University of Wisconsin-Madison, Department of Biomolecular Chemistry
| | - John-Paul J. Yu
- University of Wisconsin-Madison, Department of Radiology, Division of Neuroradiology
| | | | - Tyler K. Ulland
- University of Wisconsin-Madison, Department of Pathology and Laboratory Medicine
| |
Collapse
|
7
|
Buawangpong N, Pinyopornpanish K, Siri-Angkul N, Chattipakorn N, Chattipakorn SC. The role of trimethylamine-N-Oxide in the development of Alzheimer's disease. J Cell Physiol 2021; 237:1661-1685. [PMID: 34812510 DOI: 10.1002/jcp.30646] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 11/07/2021] [Accepted: 11/09/2021] [Indexed: 02/06/2023]
Abstract
Alzheimer's disease is associated with multiple risk factors and is the most common type of dementia. Trimethylamine-N-oxide (TMAO), a gut microbiota metabolite derived from dietary choline and carnitine, has recently been identified as a potential risk factor of Alzheimer's disease. It has been demonstrated that TMAO is associated with Alzheimer's disease through various pathophysiological pathways. As a result of molecular crowding effects, TMAO causes the aggregation of the two proteins, amyloid-beta peptide and tau protein. The aggregation of these proteins is the main pathology associated with Alzheimer's disease. In addition, it has been found that TMAO can activate astrocytes, and inflammatory response. Besides molecular investigation, animal and human studies have also supported the existence of a functional relationship between TMAO and cognitive decline. This article comprehensively summarizes the relationship between TMAO and Alzheimer's disease including emerging evidence from in vitro, in vivo, and clinical studies. We hope that this knowledge will improve the prevention and treatment of Alzheimer's disease in the near future.
Collapse
Affiliation(s)
- Nida Buawangpong
- Department of Family Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | - Natthapat Siri-Angkul
- Department of Physiology, Cardiac Electrophysiology Unit, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University Chiang Mai, Chiang Mai, Thailand
| | - Nipon Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Department of Physiology, Cardiac Electrophysiology Unit, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University Chiang Mai, Chiang Mai, Thailand
| | - Siriporn C Chattipakorn
- Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.,Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University Chiang Mai, Chiang Mai, Thailand.,Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| |
Collapse
|
8
|
Chatterjee S, Choi AJ, Frankel G. A systematic review of Sec24 cargo interactome. Traffic 2021; 22:412-424. [PMID: 34533884 DOI: 10.1111/tra.12817] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/27/2021] [Accepted: 09/13/2021] [Indexed: 01/10/2023]
Abstract
Endoplasmic reticulum (ER)-to-Golgi trafficking is an essential and highly conserved cellular process. The coat protein complex-II (COPII) arm of the trafficking machinery incorporates a wide array of cargo proteins into vesicles through direct or indirect interactions with Sec24, the principal subunit of the COPII coat. Approximately one-third of all mammalian proteins rely on the COPII-mediated secretory pathway for membrane insertion or secretion. There are four mammalian Sec24 paralogs and three yeast Sec24 paralogs with emerging evidence of paralog-specific cargo interaction motifs. Furthermore, individual paralogs also differ in their affinity for a subset of sorting motifs present on cargo proteins. As with many aspects of protein trafficking, we lack a systematic and thorough understanding of the interaction of Sec24 with cargoes. This systematic review focuses on the current knowledge of cargo binding to both yeast and mammalian Sec24 paralogs and their ER export motifs. The analyses show that Sec24 paralog specificity of cargo (and cargo receptors) range from exclusive paralog dependence or preference to partial redundancy. We also discuss how the Sec24 secretion system is hijacked by viral (eg, VSV-G, Hepatitis B envelope protein) and bacterial (eg, the enteropathogenic Escherichia coli type III secretion system effector NleA/EspI) pathogens.
Collapse
Affiliation(s)
- Sharanya Chatterjee
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Ana Jeemin Choi
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| | - Gad Frankel
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College, London, UK
| |
Collapse
|
9
|
An in vitro vesicle formation assay reveals cargo clients and factors that mediate vesicular trafficking. Proc Natl Acad Sci U S A 2021; 118:2101287118. [PMID: 34433667 PMCID: PMC8536394 DOI: 10.1073/pnas.2101287118] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protein sorting in the secretory pathway is a fundamentally important cellular process, but the clients of a specific cargo sorting machinery remains largely underinvestigated. Here, utilizing a vesicle formation assay to profile proteins associated with vesicles, we identified cytosolic proteins that are associated with vesicle membranes in a GTP-dependent manner or that interact with GTP-bound Sar1A. We found that two of them, FAM84B and PRRC1, regulate anterograde trafficking. Moreover, we revealed specific clients of two export adaptors, SURF4 and ERGIC53. These analyses demonstrate that our approach is powerful to identify factors that regulate vesicular trafficking and to uncover clients of specific cargo receptors, providing a robust method to reveal insights into the secretory pathway. The fidelity of protein transport in the secretory pathway relies on the accurate sorting of proteins to their correct destinations. To deepen our understanding of the underlying molecular mechanisms, it is important to develop a robust approach to systematically reveal cargo proteins that depend on specific sorting machinery to be enriched into transport vesicles. Here, we used an in vitro assay that reconstitutes packaging of human cargo proteins into vesicles to quantify cargo capture. Quantitative mass spectrometry (MS) analyses of the isolated vesicles revealed cytosolic proteins that are associated with vesicle membranes in a GTP-dependent manner. We found that two of them, FAM84B (also known as LRAT domain containing 2 or LRATD2) and PRRC1, contain proline-rich domains and regulate anterograde trafficking. Further analyses revealed that PRRC1 is recruited to endoplasmic reticulum (ER) exit sites, interacts with the inner COPII coat, and its absence increases membrane association of COPII. In addition, we uncovered cargo proteins that depend on GTP hydrolysis to be captured into vesicles. Comparing control cells with cells depleted of the cargo receptors, SURF4 or ERGIC53, we revealed specific clients of each of these two export adaptors. Our results indicate that the vesicle formation assay in combination with quantitative MS analysis is a robust and powerful tool to uncover novel factors that mediate vesicular trafficking and to uncover cargo clients of specific cellular factors.
Collapse
|
10
|
Smit T, Deshayes NAC, Borchelt DR, Kamphuis W, Middeldorp J, Hol EM. Reactive astrocytes as treatment targets in Alzheimer's disease-Systematic review of studies using the APPswePS1dE9 mouse model. Glia 2021; 69:1852-1881. [PMID: 33634529 PMCID: PMC8247905 DOI: 10.1002/glia.23981] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 12/15/2022]
Abstract
Astrocytes regulate synaptic communication and are essential for proper brain functioning. In Alzheimer's disease (AD) astrocytes become reactive, which is characterized by an increased expression of intermediate filament proteins and cellular hypertrophy. Reactive astrocytes are found in close association with amyloid-beta (Aβ) deposits. Synaptic communication and neuronal network function could be directly modulated by reactive astrocytes, potentially contributing to cognitive decline in AD. In this review, we focus on reactive astrocytes as treatment targets in AD in the APPswePS1dE9 AD mouse model, a widely used model to study amyloidosis and gliosis. We first give an overview of the model; that is, how it was generated, which cells express the transgenes, and the effect of its genetic background on Aβ pathology. Subsequently, to determine whether modifying reactive astrocytes in AD could influence pathogenesis and cognition, we review studies using this mouse model in which interventions were directly targeted at reactive astrocytes or had an indirect effect on reactive astrocytes. Overall, studies specifically targeting astrocytes to reduce astrogliosis showed beneficial effects on cognition, which indicates that targeting astrocytes should be included in developing novel therapies for AD.
Collapse
Affiliation(s)
- Tamar Smit
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
- Swammerdam Institute for Life SciencesCenter for Neuroscience, University of AmsterdamAmsterdamThe Netherlands
| | - Natasja A. C. Deshayes
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
- Swammerdam Institute for Life SciencesCenter for Neuroscience, University of AmsterdamAmsterdamThe Netherlands
| | - David R. Borchelt
- Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, Department of NeuroscienceUniversity of Florida College of MedicineGainesvilleFloridaUSA
| | - Willem Kamphuis
- Netherlands Institute for NeuroscienceAn Institute of the Royal Netherlands Academy of Arts and SciencesAmsterdamThe Netherlands
| | - Jinte Middeldorp
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
- Department of ImmunobiologyBiomedical Primate Research CentreRijswijkThe Netherlands
| | - Elly M. Hol
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
| |
Collapse
|
11
|
Wouters R, Michiels C, Sannerud R, Kleizen B, Dillen K, Vermeire W, Ayala AE, Demedts D, Schekman R, Annaert W. Assembly of γ-secretase occurs through stable dimers after exit from the endoplasmic reticulum. J Cell Biol 2021; 220:212501. [PMID: 34292306 PMCID: PMC8302450 DOI: 10.1083/jcb.201911104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/29/2020] [Accepted: 06/07/2021] [Indexed: 01/22/2023] Open
Abstract
γ-Secretase affects many physiological processes through targeting >100 substrates; malfunctioning links γ-secretase to cancer and Alzheimer’s disease. The spatiotemporal regulation of its stoichiometric assembly remains unresolved. Fractionation, biochemical assays, and imaging support prior formation of stable dimers in the ER, which, after ER exit, assemble into full complexes. In vitro ER budding shows that none of the subunits is required for the exit of others. However, knockout of any subunit leads to the accumulation of incomplete subcomplexes in COPII vesicles. Mutating a DPE motif in presenilin 1 (PSEN1) abrogates ER exit of PSEN1 and PEN-2 but not nicastrin. We explain this by the preferential sorting of PSEN1 and nicastrin through Sec24A and Sec24C/D, respectively, arguing against full assembly before ER exit. Thus, dimeric subcomplexes aided by Sec24 paralog selectivity support a stepwise assembly of γ-secretase, controlling final levels in post-Golgi compartments.
Collapse
Affiliation(s)
- Rosanne Wouters
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Christine Michiels
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Ragna Sannerud
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Bertrand Kleizen
- Cellular Protein Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Katleen Dillen
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Wendy Vermeire
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Abril Escamilla Ayala
- Vlaams Instituut voor Biotechnologie BioImaging Core, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Leuven, Belgium
| | - David Demedts
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Randy Schekman
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA
| | - Wim Annaert
- Laboratory for Membrane Trafficking, Vlaams Instituut voor Biotechnologie Center for Brain and Disease Research, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| |
Collapse
|
12
|
Escamilla-Ayala A, Wouters R, Sannerud R, Annaert W. Contribution of the Presenilins in the cell biology, structure and function of γ-secretase. Semin Cell Dev Biol 2020; 105:12-26. [DOI: 10.1016/j.semcdb.2020.02.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/06/2020] [Accepted: 02/17/2020] [Indexed: 01/25/2023]
|
13
|
Tang X, Zhang L, Ma T, Wang M, Li B, Jiang L, Yan Y, Guo Y. Molecular mechanisms that regulate export of the planar cell-polarity protein Frizzled-6 out of the endoplasmic reticulum. J Biol Chem 2020; 295:8972-8987. [PMID: 32376691 PMCID: PMC7335806 DOI: 10.1074/jbc.ra120.012835] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/30/2020] [Indexed: 01/05/2023] Open
Abstract
Planar cell polarity (PCP) is a process during which cells are polarized along the plane of the epithelium and is regulated by several transmembrane signaling proteins. After their synthesis, these PCP proteins are delivered along the secretory transport pathway to the plasma membrane, where they perform their physiological functions. However, the molecular mechanisms that regulate PCP protein transport remain largely unclear. Here, we found that the delivery of a PCP protein, Frizzled-6, to the cell surface is regulated by two conserved polybasic motifs: one located in its first intracellular loop and the other in its C-terminal cytosolic domain. We observed that the polybasic motif of Frizzled is also important for its surface localization in the Drosophila wing. Results from a mechanistic analysis indicated that Frizzled-6 packaging into vesicles at the endoplasmic reticulum (ER) is regulated by a direct interaction between the polybasic motif and the Glu-62 and Glu-63 residues on the secretion-associated Ras-related GTPase 1A (SAR1A) subunit of coat protein complex II (COPII). Moreover, we found that newly synthesized Frizzled-6 is associated with another PCP protein, cadherin EGF LAG seven-pass G-type receptor 1 (CELSR1), in the secretory transport pathway, and that this association regulates their surface delivery. Our results reveal insights into the molecular machinery that regulates the ER export of Frizzled-6. They also suggest that the association of CELSR1 with Frizzled-6 is important, enabling efficient Frizzled-6 delivery to the cell surface, providing a quality control mechanism that ensures the appropriate stoichiometry of these two PCP proteins at cell boundaries.
Collapse
Affiliation(s)
- Xiao Tang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Lina Zhang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Tianji Ma
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Mo Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Baiying Li
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- School of Life Sciences, Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yan Yan
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yusong Guo
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China; Hong Kong University of Science and Technology Shenzhen Research Institute, Shenzhen, China.
| |
Collapse
|
14
|
Tang X, Yang F, Guo Y. Cell-free Reconstitution of the Packaging of Cargo Proteins into Vesicles at the trans Golgi Network. Bio Protoc 2020; 10:e3537. [PMID: 33659511 DOI: 10.21769/bioprotoc.3537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 01/07/2020] [Accepted: 01/10/2020] [Indexed: 11/02/2022] Open
Abstract
Protein sorting at the trans Golgi network (TGN) plays important roles in targeting newly synthesized proteins to their specific destinations. The aim of this proposal is to reconstitute the packaging of non-Golgi resident cargo proteins into vesicles at the TGN, utilizing rat liver cytosol, semi-intact mammalian cells and nucleotides. The protocol describes how to perform the vesicle formation assay, how to isolate vesicles and how to detect cargo proteins in vesicles. This reconstitution assay can be used to quantitatively measure the efficiency of the packaging of a specific cargo protein into transport vesicles at the TGN under specific experimental conditions.
Collapse
Affiliation(s)
- Xiao Tang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Feng Yang
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yusong Guo
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong, China
| |
Collapse
|
15
|
Zhang S, Xiao T, Yu Y, Qiao Y, Xu Z, Geng J, Liang Y, Mei Y, Dong Q, Wang B, Wei J, Suo G. The extracellular matrix enriched with membrane metalloendopeptidase and insulin‐degrading enzyme suppresses the deposition of amyloid‐beta peptide in Alzheimer's disease cell models. J Tissue Eng Regen Med 2019; 13:1759-1769. [DOI: 10.1002/term.2906] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 12/15/2018] [Accepted: 02/13/2019] [Indexed: 01/04/2023]
Affiliation(s)
- Shumang Zhang
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
- School of Life SciencesShanghai University Shanghai China
| | - Tongqian Xiao
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
- University of Chinese Academy of Sciences Beijing China
| | - Yanzhen Yu
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of China Hefei China
| | - Yong Qiao
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
| | - Zhongjuan Xu
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of China Hefei China
| | - Junsa Geng
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
- School of Nano‐Tech and Nano‐BionicsUniversity of Science and Technology of China Hefei China
| | - Yu Liang
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
- School of Life SciencesShanghai University Shanghai China
| | - Yan Mei
- Greepharma Inc. Nanjing China
| | - Qun Dong
- Department of PathologyTaikang Xianlin Drum Tower Hospital Nanjing China
| | - Bin Wang
- Center for Clinic Stem Cell ResearchThe Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing China
| | - Jiali Wei
- School of Life SciencesShanghai University Shanghai China
| | - Guangli Suo
- CAS Key Laboratory of Nano‐Bio InterfaceSuzhou Institute of Nano‐Tech and Nano‐Bionics, Chinese Academy of Sciences Jiangsu China
| |
Collapse
|
16
|
Wang L, Mazagova M, Pan C, Yang S, Brandl K, Liu J, Reilly SM, Wang Y, Miao Z, Loomba R, Lu N, Guo Q, Liu J, Yu RT, Downes M, Evans RM, Brenner DA, Saltiel AR, Beutler B, Schnabl B. YIPF6 controls sorting of FGF21 into COPII vesicles and promotes obesity. Proc Natl Acad Sci U S A 2019; 116:15184-15193. [PMID: 31289229 PMCID: PMC6660779 DOI: 10.1073/pnas.1904360116] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Fibroblast growth factor 21 (FGF21) is an endocrine hormone that regulates glucose, lipid, and energy homeostasis. While gene expression of FGF21 is regulated by the nuclear hormone receptor peroxisome proliferator-activated receptor alpha in the fasted state, little is known about the regulation of trafficking and secretion of FGF21. We show that mice with a mutation in the Yip1 domain family, member 6 gene (Klein-Zschocher [KLZ]; Yipf6KLZ/Y ) on a high-fat diet (HFD) have higher plasma levels of FGF21 than mice that do not carry this mutation (controls) and hepatocytes from Yipf6KLZ/Y mice secrete more FGF21 than hepatocytes from wild-type mice. Consequently, Yipf6KLZ/Y mice are resistant to HFD-induced features of the metabolic syndrome and have increased lipolysis, energy expenditure, and thermogenesis, with an increase in core body temperature. Yipf6KLZ/Y mice with hepatocyte-specific deletion of FGF21 were no longer protected from diet-induced obesity. We show that YIPF6 binds FGF21 in the endoplasmic reticulum to limit its secretion and specifies packaging of FGF21 into coat protein complex II (COPII) vesicles during development of obesity in mice. Levels of YIPF6 protein in human liver correlate with hepatic steatosis and correlate inversely with levels of FGF21 in serum from patients with nonalcoholic fatty liver disease (NAFLD). YIPF6 is therefore a newly identified regulator of FGF21 secretion during development of obesity and could be a target for treatment of obesity and NAFLD.
Collapse
Affiliation(s)
- Lirui Wang
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China;
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
- Department of Medicine, VA San Diego Healthcare System, San Diego, CA 92161
| | - Magdalena Mazagova
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Chuyue Pan
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Song Yang
- Department of Hepatology, Beijing Ditan Hospital, Capital Medical University, Chaoyang District, 100015 Beijing, China
| | - Katharina Brandl
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093
| | - Jun Liu
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Shannon M Reilly
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Yanhan Wang
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Zhaorui Miao
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Rohit Loomba
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Na Lu
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Qinglong Guo
- School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Jihua Liu
- School of Traditional Chinese Pharmacy, China Pharmaceutical University, 211198 Nanjing, Jiang Su, China
| | - Ruth T Yu
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Michael Downes
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Ronald M Evans
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - David A Brenner
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Alan R Saltiel
- Department of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Bruce Beutler
- Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Bernd Schnabl
- Department of Medicine, University of California San Diego, La Jolla, CA 92093;
- Department of Medicine, VA San Diego Healthcare System, San Diego, CA 92161
| |
Collapse
|
17
|
Aridor M. COPII gets in shape: Lessons derived from morphological aspects of early secretion. Traffic 2018; 19:823-839. [DOI: 10.1111/tra.12603] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 06/26/2018] [Accepted: 07/04/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Meir Aridor
- Department of Cell Biology; University of Pittsburgh School of Medicine; Pittsburgh Pennsylvania
| |
Collapse
|
18
|
Abstract
The flow of cargo vesicles along the secretory pathway requires concerted action among various regulators. The COPII complex, assembled by the activated SAR1 GTPases on the surface of the endoplasmic reticulum, orchestrates protein interactions to package cargos and generate transport vesicles en route to the Golgi. The dynamic nature of COPII, however, hinders analysis with conventional biochemical assays. Here we apply proximity-dependent biotinylation labeling to capture the dynamics of COPII transport in cells. When SAR1B was fused with a promiscuous biotin ligase, BirA*, the fusion protein SAR1B-BirA* biotinylates and thus enables the capture of COPII machinery and cargos in a GTP-dependent manner. Biochemical and pulse-chase imaging experiments demonstrate that the COPII coat undergoes a dynamic cycle of engagement-disengagement with the transmembrane cargo receptor LMAN1/ERGIC53. LMAN1 undergoes a process of concentrative sorting by the COPII coat, via a dimeric sorting code generated by oligomerization of the cargo receptor. Similar oligomerization events have been observed with other COPII sorting signals, suggesting that dimeric/multimeric sorting codes may serve as a general mechanism to generate selectivity of cargo sorting.
Collapse
|
19
|
Sirkis DW, Aparicio RE, Schekman R. Neurodegeneration-associated mutant TREM2 proteins abortively cycle between the ER and ER-Golgi intermediate compartment. Mol Biol Cell 2017; 28:2723-2733. [PMID: 28768830 PMCID: PMC5620379 DOI: 10.1091/mbc.e17-06-0423] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 07/28/2017] [Accepted: 07/28/2017] [Indexed: 11/21/2022] Open
Abstract
Mutations in the microglial cell surface receptor TREM2 are associated with multiple forms of neurodegeneration. Several of these mutant forms of TREM2 were thought to be retained in the endoplasmic reticulum (ER), but careful analysis reveals that they engage in an abortive cycling pathway between the ER and ER–Golgi intermediate compartment. Triggering receptor expressed on myeloid cells 2 (TREM2) is a transmembrane protein expressed on microglia within the brain. Several rare mutations in TREM2 cause an early-onset form of neurodegeneration when inherited homozygously. Here we investigate how these mutations affect the intracellular transport of TREM2. We find that most pathogenic TREM2 mutant proteins fail to undergo normal maturation in the Golgi complex and show markedly reduced cell-surface expression. Prior research has suggested that two such mutants are retained in the endoplasmic reticulum (ER), but we find, using a cell-free coat protein complex II (COPII) vesicle budding reaction, that mutant TREM2 is exported efficiently from the ER. In addition, mutant TREM2 becomes sensitive to cleavage by endoglycosidase D under conditions that inhibit recycling to the ER, indicating that it normally reaches a post-ER compartment. Maturation-defective TREM2 mutants are also efficiently bound by a lectin that recognizes O-glycans added in the ER–Golgi intermediate compartment (ERGIC) and cis-Golgi cisterna. Finally, mutant TREM2 accumulates in the ERGIC in cells depleted of COPI. These results indicate that efficient ER export is not sufficient to enable normal cell-surface expression of TREM2. Moreover, our findings suggest that the ERGIC may play an underappreciated role as a quality-control center for mutant and/or malformed membrane proteins.
Collapse
Affiliation(s)
- Daniel W Sirkis
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720
| | - Renan E Aparicio
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720
| | - Randy Schekman
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720
| |
Collapse
|
20
|
Ma W, Goldberg E, Goldberg J. ER retention is imposed by COPII protein sorting and attenuated by 4-phenylbutyrate. eLife 2017; 6. [PMID: 28594326 PMCID: PMC5464768 DOI: 10.7554/elife.26624] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 04/18/2017] [Indexed: 01/07/2023] Open
Abstract
Native cargo proteins exit the endoplasmic reticulum (ER) in COPII-coated vesicles, whereas resident and misfolded proteins are substantially excluded from vesicles by a retention mechanism that remains unresolved. We probed the ER retention process using the proteostasis regulator 4-phenylbutyrate (4-PBA), which we show targets COPII protein to reduce the stringency of retention. 4-PBA competes with p24 proteins to bind COPII. When p24 protein uptake is blocked, COPII vesicles package resident proteins and an ER-trapped mutant LDL receptor. We further show that 4-PBA triggers the secretion of a KDEL-tagged luminal resident, implying that a compromised retention mechanism causes saturation of the KDEL retrieval system. The results indicate that stringent ER retention requires the COPII coat machinery to actively sort biosynthetic cargo from diffusible misfolded and resident ER proteins. DOI:http://dx.doi.org/10.7554/eLife.26624.001
Collapse
Affiliation(s)
- Wenfu Ma
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Elena Goldberg
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Jonathan Goldberg
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States.,Howard Hughes Medical Institute, New York, United States
| |
Collapse
|
21
|
Zhao S, Li CM, Luo XM, Siu GKY, Gan WJ, Zhang L, Wu WKK, Chan HC, Yu S. Mammalian TRAPPIII Complex positively modulates the recruitment of Sec13/31 onto COPII vesicles. Sci Rep 2017; 7:43207. [PMID: 28240221 PMCID: PMC5327430 DOI: 10.1038/srep43207] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 01/23/2017] [Indexed: 11/09/2022] Open
Abstract
The Transport protein particle (TRAPP) complex is a tethering factor for COPII vesicle. Of three forms of TRAPP (TRAPPI, II and III) complexes identified so far, TRAPPIII has been largely considered to play a role in autophagy. While depletion of TRAPPIII specific subunits caused defects in the early secretory pathway and TRAPPIII might interact with components of the COPII vesicle coat, its exact role remains to be determined. In this study, we studied the function of TRAPPIII in early secretory pathway using a TRAPPIII-specific subunit, TRAPPC12, as starting point. We found that TRAPPC12 was localized to the ER exit sites and ERGIC. In cells deleted with TRAPPC12, ERGIC and to a lesser extent, the Golgi became dispersed. ER-to-Golgi transport was also delayed. TRAPPC12, but not TRAPPC8, bound to Sec13/Sec31A tetramer but each Sec protein alone could not interact with TRAPPC12. TRAPPIII positively modulated the assembly of COPII outer layer during COPII vesicle formation. These results identified a novel function of TRAPPIII as a positive modulator of the outer layer of the COPII coat.
Collapse
Affiliation(s)
- Shan Zhao
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| | - Chun Man Li
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| | - Xiao Min Luo
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| | - Gavin Ka Yu Siu
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| | - Wen Jia Gan
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| | - Lin Zhang
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China.,Department of anesthesia, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, P.R. China
| | - William K K Wu
- Department of anesthesia, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, P.R. China
| | - Hsiao Chang Chan
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China.,Epithelial Cell Biology Research Centre, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| | - Sidney Yu
- School of Biomedical Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China.,Epithelial Cell Biology Research Centre, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong SAR, P.R. China
| |
Collapse
|
22
|
Lee H, Noh H, Mun J, Gu C, Sever S, Park S. Anks1a regulates COPII-mediated anterograde transport of receptor tyrosine kinases critical for tumorigenesis. Nat Commun 2016; 7:12799. [PMID: 27619642 PMCID: PMC5027278 DOI: 10.1038/ncomms12799] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 08/02/2016] [Indexed: 02/06/2023] Open
Abstract
ErbB2 signalling, which is amplified by EphA2 binding, is an important therapeutic target for breast cancer. Despite the importance of the EphA2/ErbB2 complex in promoting breast tumorigenesis, the mechanism by which these receptor tyrosine kinases (RTKs) are exported from the endoplasmic reticulum (ER) remains poorly understood. Here we report that the PTB adaptor Anks1a is specifically localized to the ER on its own serine phosphorylation. Once there, Anks1a acts as an important regulator of COPII-mediated EphA2 ER export. The Anks1a ankyrin repeat domain binds EphA2 and causes it to accumulate at sites of ER exit. Simultaneously, the Anks1a PTB domain binds Sec23. This induces internalization of EphA2 via COPII vesicles, while Anks1a remains behind on the ER membrane. EphA2 also binds ErbB2 in the ER and seems to load ErbB2 into growing COPII carriers. Together, our study reveals a novel mechanism that regulates the loading of RTKs into COPII vesicles. EphA2/ErbB2 complex is important in promoting breast cancer but the mechanism by which these receptor tyrosine kinases are exported from the endoplasmic reticulum is unknown. Here the authors show that Anks1a acts as a cargo adaptor in sorting EphA2 into COPII vesicles, thus modulating the surface level of EphA2.
Collapse
Affiliation(s)
- Haeryung Lee
- Department of Biological Science, Sookmyung Women's University, Chungpa-ro 47gil 100, Yongsan-gu, Seoul 140-742, Korea
| | - Hyuna Noh
- Department of Biological Science, Sookmyung Women's University, Chungpa-ro 47gil 100, Yongsan-gu, Seoul 140-742, Korea
| | - Jiyoung Mun
- Department of Biomedical Laboratory Science, College of Health Science, Eulji University, Seongnam-Si, Gyeonggi-Do 13135, Korea
| | - Changkyu Gu
- Division of Nephrology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
| | - Sanja Sever
- Division of Nephrology, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
| | - Soochul Park
- Department of Biological Science, Sookmyung Women's University, Chungpa-ro 47gil 100, Yongsan-gu, Seoul 140-742, Korea
| |
Collapse
|
23
|
Kanatsu K, Tomita T. Membrane trafficking and proteolytic activity of γ-secretase in Alzheimer’s disease. Biol Chem 2016; 397:827-35. [DOI: 10.1515/hsz-2016-0146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 07/04/2016] [Indexed: 12/26/2022]
Abstract
Abstract
γ-Secretase is an intramembrane-cleaving protease that generates various forms of amyloid-β peptides (Aβ) that accumulate in the brains of Alzheimer’s disease (AD) patients. The intracellular trafficking and subcellular localization of γ-secretase are linked to both qualitative and quantitative changes in Aβ production. However, the precise intracellular localization of γ-secretase as well as its detailed regulatory mechanisms have remained elusive. Recent genetic studies on AD provide ample evidence that alteration of the subcellular localization of γ-secretase contributes to the pathogenesis of AD. Here we review our current understanding of the intracellular membrane trafficking of γ-secretase, the association between its localization and proteolytic activity, and the possibility of γ-secretase as a therapeutic target against AD.
Collapse
|
24
|
Fang J, Liu M, Zhang X, Sakamoto T, Taatjes DJ, Jena BP, Sun F, Woods J, Bryson T, Kowluru A, Zhang K, Chen X. COPII-Dependent ER Export: A Critical Component of Insulin Biogenesis and β-Cell ER Homeostasis. Mol Endocrinol 2015; 29:1156-69. [PMID: 26083833 DOI: 10.1210/me.2015-1012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pancreatic β-cells possess a highly active protein synthetic and export machinery in the endoplasmic reticulum (ER) to accommodate the massive production of proinsulin. ER homeostasis is vital for β-cell functions and is maintained by the delicate balance between protein synthesis, folding, export, and degradation. Disruption of ER homeostasis by diabetes-causing factors leads to β-cell death. Among the 4 components to maintain ER homeostasis in β-cells, the role of ER export in insulin biogenesis is the least understood. To address this knowledge gap, the present study investigated the molecular mechanism of proinsulin ER export in MIN6 cells and primary islets. Two inhibitory mutants of the secretion-associated RAS-related protein (Sar)1 small GTPase, known to specifically block coat protein complex II (COPII)-dependent ER export, were overexpressed in β-cells using recombinant adenoviruses. Results from this approach, as well as small interfering RNA-mediated Sar1 knockdown, demonstrated that defective Sar1 function blocked proinsulin ER export and abolished its conversion to mature insulin in MIN6 cells, isolated mouse, and human islets. It is further revealed, using an in vitro vesicle formation assay, that proinsulin was packaged into COPII vesicles in a GTP- and Sar1-dependent manner. Blockage of COPII-dependent ER exit by Sar1 mutants strongly induced ER morphology change, ER stress response, and β-cell apoptosis. These responses were mediated by the PKR (double-stranded RNA-dependent kinase)-like ER kinase (PERK)/eukaryotic translation initiation factor 2α (p-eIF2α) and inositol-requiring protein 1 (IRE1)/x-box binding protein 1 (Xbp1) pathways but not via activating transcription factor 6 (ATF6). Collectively, results from the study demonstrate that COPII-dependent ER export plays a vital role in insulin biogenesis, ER homeostasis, and β-cell survival.
Collapse
Affiliation(s)
- Jingye Fang
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Ming Liu
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Xuebao Zhang
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Takeshi Sakamoto
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Douglas J Taatjes
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Bhanu P Jena
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Fei Sun
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - James Woods
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Tim Bryson
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Anjaneyulu Kowluru
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Kezhong Zhang
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - Xuequn Chen
- Department of Physiology (J.F., B.P.J., F.S., J.W., T.B., X.C.) and Center for Molecular Medicine and Genetics (X.Z., K.Z.), School of Medicine, Department of Physics and Astronomy (T.S.), College of Liberal Arts and Sciences, and Department of Pharmaceutical Sciences (A.K.), Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, and John D. Dingell VA Medical Center (A.K.), Detroit, Michigan 48201; Department of Internal Medicine (M.L.), University of Michigan, Ann Arbor, Michigan 48109; and Department of Pathology (D.J.T.), Microscopy Imaging Center, University of Vermont College of Medicine, Burlington, Vermont 05405
| |
Collapse
|
25
|
de Laat R, Meabon JS, Wiley JC, Hudson MP, Montine TJ, Bothwell M. LINGO-1 promotes lysosomal degradation of amyloid-β protein precursor. PATHOBIOLOGY OF AGING & AGE RELATED DISEASES 2015; 5:25796. [PMID: 25758563 PMCID: PMC4355507 DOI: 10.3402/pba.v5.25796] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 02/04/2015] [Accepted: 02/10/2015] [Indexed: 11/24/2022]
Abstract
Sequential proteolytic cleavages of amyloid-β protein precursor (AβPP) by β-secretase and γ-secretase generate amyloid β (Aβ) peptides, which are thought to contribute to Alzheimer's disease (AD). Much of this processing occurs in endosomes following endocytosis of AβPP from the plasma membrane. However, this pathogenic mode of processing AβPP may occur in competition with lysosomal degradation of AβPP, a common fate of membrane proteins trafficking through the endosomal system. Following up on published reports that LINGO-1 binds and promotes the amyloidogenic processing of AβPP we have examined the consequences of LINGO-1/AβPP interactions. We report that LINGO-1 and its paralogs, LINGO-2 and LINGO-3, decrease processing of AβPP in the amyloidogenic pathway by promoting lysosomal degradation of AβPP. We also report that LINGO-1 levels are reduced in AD brain, representing a possible pathogenic mechanism stimulating the generation of Aβ peptides in AD.
Collapse
Affiliation(s)
| | - James S Meabon
- Department of Psychiatry and Behavioral Sciences, University of Washington and Mental Illness Research Education and Clinical Center, VA Medical Center, Seattle, WA, USA
| | - Jesse C Wiley
- Department of Comparative Medicine, University of Washington, Seattle, WA, USA
| | - Mark P Hudson
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA
| | - Thomas J Montine
- Department of Pathology, University of Washington, Seattle, WA, USA
| | - Mark Bothwell
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA.,Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA;
| |
Collapse
|
26
|
Suga K, Saito A, Akagawa K. ER stress response in NG108-15 cells involves upregulation of syntaxin 5 expression and reduced amyloid β peptide secretion. Exp Cell Res 2015; 332:11-23. [DOI: 10.1016/j.yexcr.2015.01.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 01/05/2015] [Accepted: 01/07/2015] [Indexed: 01/24/2023]
|
27
|
The PERK pathway independently triggers apoptosis and a Rac1/Slpr/JNK/Dilp8 signaling favoring tissue homeostasis in a chronic ER stress Drosophila model. Cell Death Dis 2014; 5:e1452. [PMID: 25299777 PMCID: PMC4649510 DOI: 10.1038/cddis.2014.403] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 08/15/2014] [Accepted: 08/18/2014] [Indexed: 12/11/2022]
Abstract
The endoplasmic reticulum (ER) has a major role in protein folding. The accumulation of unfolded proteins in the ER induces a stress, which can be resolved by the unfolded protein response (UPR). Chronicity of ER stress leads to UPR-induced apoptosis and in turn to an unbalance of tissue homeostasis. Although ER stress-dependent apoptosis is observed in a great number of devastating human diseases, how cells activate apoptosis and promote tissue homeostasis after chronic ER stress remains poorly understood. Here, using the Drosophila wing imaginal disc as a model system, we validated that Presenilin overexpression induces chronic ER stress in vivo. We observed, in this novel model of chronic ER-stress, a PERK/ATF4-dependent apoptosis requiring downregulation of the antiapoptotic diap1 gene. PERK/ATF4 also activated the JNK pathway through Rac1 and Slpr activation in apoptotic cells, leading to the expression of Dilp8. This insulin-like peptide caused a developmental delay, which partially allowed the replacement of apoptotic cells. Thanks to a novel chronic ER stress model, these results establish a new pathway that both participates in tissue homeostasis and triggers apoptosis through an original regulation.
Collapse
|
28
|
Abstract
Presenilin is a membrane-embedded intramembrane-cleaving protease with a conserved catalytic G×GD motif. It is the catalytic subunit of γ-secretase, which plays critical roles in developmental biology and the molecular etiology of Alzheimer disease, together with three membrane protein cofactors, nicastrin, Aph-1 and Pen-2. Biochemical and enzymatic analyses have revealed that γ-secretase executes two types of proteolytic activities on a single substrate; an endopeptidase-like cleavage followed by carboxypeptidase-like processive cleavage. Utilizing small molecule inhibitors/modulators together with the substituted cysteine accessibility method, we identified certain residues and regions of presenilin that contribute to the formation of a catalytic pore structure within the lipid bilayer required for its intramembrane-cleaving activity. Recently, determination of the crystal structure of the archaeal presenilin homologue has confirmed the intramembranous location of the two conserved and essential aspartates. In this review, I will introduce the recent progresses in the understanding of the molecular mechanisms of action of this atypical protease.
Collapse
Affiliation(s)
- Taisuke Tomita
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| |
Collapse
|
29
|
Abstract
In vitro reconstitution is prerequisite to investigate complex cellular functions at the molecular level. Reconstitution systems range from combining complete cellular cytosol with organelle-enriched membrane fractions to liposomal systems where all components are chemically defined and can be chosen at will. Here, we describe the in vitro reconstitution of COPI-coated vesicles from semi-intact cells. Efficient vesicle formation is achieved by simple incubation of permeabilized cells with the minimal set of coat proteins Arf1 and coatomer, and guanosine trinucleotides. GTP hydrolysis or any mechanical manipulations are not required for efficient COPI vesicle release.
Collapse
|
30
|
Krämer A, Mentrup T, Kleizen B, Rivera-Milla E, Reichenbach D, Enzensperger C, Nohl R, Täuscher E, Görls H, Ploubidou A, Englert C, Werz O, Arndt HD, Kaether C. Small molecules intercept Notch signaling and the early secretory pathway. Nat Chem Biol 2013; 9:731-8. [PMID: 24077179 DOI: 10.1038/nchembio.1356] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 09/04/2013] [Indexed: 12/17/2022]
Abstract
Notch signaling has a pivotal role in numerous cell-fate decisions, and its aberrant activity leads to developmental disorders and cancer. To identify molecules that influence Notch signaling, we screened nearly 17,000 compounds using automated microscopy to monitor the trafficking and processing of a ligand-independent Notch-enhanced GFP (eGFP) reporter. Characterization of hits in vitro by biochemical and cellular assays and in vivo using zebrafish led to five validated compounds, four of which induced accumulation of the reporter at the plasma membrane by inhibiting γ-secretase. One compound, the dihydropyridine FLI-06, disrupted the Golgi apparatus in a manner distinct from that of brefeldin A and golgicide A. FLI-06 inhibited general secretion at a step before exit from the endoplasmic reticulum (ER), which was accompanied by a tubule-to-sheet morphological transition of the ER, rendering FLI-06 the first small molecule acting at such an early stage in secretory traffic. These data highlight the power of phenotypic screening to enable investigations of central cellular signaling pathways.
Collapse
Affiliation(s)
- Andreas Krämer
- Leibniz Institut für Altersforschung-Fritz Lipmann Institut, Jena, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Subversion of trafficking, apoptosis, and innate immunity by type III secretion system effectors. Trends Microbiol 2013; 21:430-41. [DOI: 10.1016/j.tim.2013.06.008] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 05/08/2013] [Accepted: 06/18/2013] [Indexed: 11/17/2022]
|
32
|
Morohashi Y, Tomita T. Protein trafficking and maturation regulate intramembrane proteolysis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2855-61. [PMID: 23770323 DOI: 10.1016/j.bbamem.2013.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Revised: 05/04/2013] [Accepted: 06/03/2013] [Indexed: 12/30/2022]
Abstract
Intramembrane-cleaving proteases (I-CLiPs) are membrane embedded proteolytic enzymes. All substrates identified so far are also membrane proteins, involving a number of critical cellular signaling as well as human diseases. After synthesis and assembly at the endoplasmic reticulum, membrane proteins are exported to the Golgi apparatus and transported to their sites of action. A number of studies have revealed the importance of the intracellular membrane trafficking in i-CLiP-mediated intramembrane proteolysis, not only for limiting the unnecessary encounter between i-CLiPs and their substrate but also for their cleavage site preference. In this review, we will discuss recent advances in our understanding of how each i-CLiP proteolysis is regulated by intracellular vesicle trafficking. This article is part of a Special Issue entitled: Intramembrane Proteases.
Collapse
Affiliation(s)
- Yuichi Morohashi
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | | |
Collapse
|
33
|
Chen XW, Wang H, Bajaj K, Zhang P, Meng ZX, Ma D, Bai Y, Liu HH, Adams E, Baines A, Yu G, Sartor MA, Zhang B, Yi Z, Lin J, Young SG, Schekman R, Ginsburg D. SEC24A deficiency lowers plasma cholesterol through reduced PCSK9 secretion. eLife 2013; 2:e00444. [PMID: 23580231 PMCID: PMC3622177 DOI: 10.7554/elife.00444] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 02/19/2013] [Indexed: 12/14/2022] Open
Abstract
The secretory pathway of eukaryotic cells packages cargo proteins into COPII-coated vesicles for transport from the endoplasmic reticulum (ER) to the Golgi. We now report that complete genetic deficiency for the COPII component SEC24A is compatible with normal survival and development in the mouse, despite the fundamental role of SEC24 in COPII vesicle formation and cargo recruitment. However, these animals exhibit markedly reduced plasma cholesterol, with mutations in Apoe and Ldlr epistatic to Sec24a, suggesting a receptor-mediated lipoprotein clearance mechanism. Consistent with these data, hepatic LDLR levels are up-regulated in SEC24A-deficient cells as a consequence of specific dependence of PCSK9, a negative regulator of LDLR, on SEC24A for efficient exit from the ER. Our findings also identify partial overlap in cargo selectivity between SEC24A and SEC24B, suggesting a previously unappreciated heterogeneity in the recruitment of secretory proteins to the COPII vesicles that extends to soluble as well as trans-membrane cargoes. DOI:http://dx.doi.org/10.7554/eLife.00444.001.
Collapse
Affiliation(s)
- Xiao-Wei Chen
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
| | - He Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
| | - Kanika Bajaj
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Pengcheng Zhang
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Zhuo-Xian Meng
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
| | - Danjun Ma
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Wayne State University, Detroit, United States
| | - Yongsheng Bai
- Department of Bioinformatics, University of Michigan, Ann Arbor, United States
| | - Hui-Hui Liu
- Department of Molecular Medicine, Cleveland Clinic, Cleveland, United States
| | - Elizabeth Adams
- Program in Cell and Molecular Biology, University of Michigan, Ann Arbor, United States
| | - Andrea Baines
- Program in Cell and Molecular Biology, University of Michigan, Ann Arbor, United States
| | - Genggeng Yu
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
| | - Maureen A Sartor
- Department of Bioinformatics, University of Michigan, Ann Arbor, United States
| | - Bin Zhang
- Department of Molecular Medicine, Cleveland Clinic, Cleveland, United States
| | - Zhengping Yi
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, United States
| | - Jiandie Lin
- Life Sciences Institute, University of Michigan, Ann Arbor, United States
| | - Stephen G Young
- Department of Medicine and Human Genetics, University of California, Los Angeles, Los Angeles, United States
| | - Randy Schekman
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
| | - David Ginsburg
- Division of Molecular Medicine & Genetics, Howard Hughes Medical Institute, University of Michigan, Ann Arbor, United States
| |
Collapse
|
34
|
Lester HA, Miwa JM, Srinivasan R. Psychiatric drugs bind to classical targets within early exocytotic pathways: therapeutic effects. Biol Psychiatry 2012; 72:907-15. [PMID: 22771239 PMCID: PMC6167061 DOI: 10.1016/j.biopsych.2012.05.020] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 04/23/2012] [Accepted: 05/21/2012] [Indexed: 11/17/2022]
Abstract
The classical targets for antipsychotic and antidepressant drugs are G protein-coupled receptors and neurotransmitter transporters, respectively. Full therapeutic actions of these drugs require several weeks. We show how therapeutic effects may eventually accrue after existing therapeutic ligands bind to these classical targets, not on the plasma membrane but rather within endoplasmic reticulum (ER) and cis-Golgi. Consequences of such binding may include pharmacological chaperoning: the nascent drug targets are stabilized against degradation and can therefore exit the ER more readily. Another effect may be matchmaking: heterodimers and homodimers of the target form and can more readily exit the ER. Summarizing recent data for nicotinic receptors, we explain how such effects could lead to reduced ER stress and to a decreased unfolded protein response, including changes in gene activation and protein synthesis. In effects not directly related to cellular stress, escorting would allow increased ER exit and trafficking of known associated proteins, as well as other proteins such as growth factors and their receptors, producing both cell-autonomous and non-cell-autonomous effects. Axonal transport of relevant proteins may underlie the several weeks required for full therapy. In contrast, the antidepressant effects of ketamine and other N-methyl-D-aspartate receptor ligands, which occur within <2 hours, could arise from dendritically localized intracellular binding, followed by chaperoning, matchmaking, escorting, and reduced ER stress. Thus, the effects of intracellular binding extend beyond proteostasis of the targets themselves and involve pathways distinct from ion channel and G protein activation. We propose experimental tests and note pathophysiological correlates.
Collapse
Affiliation(s)
- Henry A Lester
- Division of Biology, California Institute of Technology, Pasadena, California.
| | | | | |
Collapse
|
35
|
Park HJ, Shabashvili D, Nekorchuk MD, Shyqyriu E, Jung JI, Ladd TB, Moore BD, Felsenstein KM, Golde TE, Kim SH. Retention in endoplasmic reticulum 1 (RER1) modulates amyloid-β (Aβ) production by altering trafficking of γ-secretase and amyloid precursor protein (APP). J Biol Chem 2012; 287:40629-40. [PMID: 23043097 PMCID: PMC3504776 DOI: 10.1074/jbc.m112.418442] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 10/05/2012] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Aβ production is influenced by intracellular trafficking of secretases and amyloid precursor protein (APP). RESULTS Retention in endoplasmic reticulum 1 (RER1) regulates the trafficking of γ-secretase and APP, thereby influences Aβ production. CONCLUSION RER1, an ER retention/retrieval factor for γ-secretase and APP, modulates Aβ production. SIGNIFICANCE RER1 and its influence on γ-secretase and APP may be implicated for a safe strategy to target Aβ production. The presence of neuritic plaques containing aggregated amyloid-β (Aβ) peptides in the brain parenchyma is a pathological hallmark of Alzheimer disease (AD). Aβ is generated by sequential cleavage of the amyloid β precursor protein (APP) by β- and γ-secretase, respectively. As APP processing to Aβ requires transport through the secretory pathway, trafficking of the substrate and access to the secretases are key factors that can influence Aβ production (Thinakaran, G., and Koo, E. H. (2008) Amyloid precursor protein trafficking, processing, and function. J. Biol. Chem. 283, 29615-29619). Here, we report that retention in endoplasmic reticulum 1 (RER1) associates with γ-secretase in early secretory compartments and regulates the intracellular trafficking of γ-secretase. RER1 overexpression decreases both γ-secretase localization on the cell surface and Aβ secretion and conversely RER1 knockdown increases the level of cell surface γ-secretase and increases Aβ secretion. Furthermore, we find that increased RER1 levels decrease mature APP and increase immature APP, resulting in less surface accumulation of APP. These data show that RER1 influences the trafficking and localization of both γ-secretase and APP, thereby regulating the production and secretion of Aβ peptides.
Collapse
Affiliation(s)
- Hyo-Jin Park
- From the Department of Pharmacology and Therapeutics, and
- the Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | | | | | - Eva Shyqyriu
- From the Department of Pharmacology and Therapeutics, and
| | - Joo In Jung
- the Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - Thomas B. Ladd
- the Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - Brenda D. Moore
- the Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - Kevin M. Felsenstein
- the Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - Todd E. Golde
- the Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - Seong-Hun Kim
- From the Department of Pharmacology and Therapeutics, and
| |
Collapse
|
36
|
Coen K, Flannagan RS, Baron S, Carraro-Lacroix LR, Wang D, Vermeire W, Michiels C, Munck S, Baert V, Sugita S, Wuytack F, Hiesinger PR, Grinstein S, Annaert W. Lysosomal calcium homeostasis defects, not proton pump defects, cause endo-lysosomal dysfunction in PSEN-deficient cells. ACTA ACUST UNITED AC 2012; 198:23-35. [PMID: 22753898 PMCID: PMC3392942 DOI: 10.1083/jcb.201201076] [Citation(s) in RCA: 163] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Presenilin (PSEN) deficiency is accompanied by accumulation of endosomes and autophagosomes, likely caused by impaired endo-lysosomal fusion. Recently, Lee et al. (2010. Cell. doi: http://dx.doi.org/10.1016/j.cell.2010.05.008) attributed this phenomenon to PSEN1 enabling the transport of mature V0a1 subunits of the vacuolar ATPase (V-ATPase) to lysosomes. In their view, PSEN1 mediates the N-glycosylation of V0a1 in the endoplasmic reticulum (ER); consequently, PSEN deficiency prevents V0a1 glycosylation, compromising the delivery of unglycosylated V0a1 to lysosomes, ultimately impairing V-ATPase function and lysosomal acidification. We show here that N-glycosylation is not a prerequisite for proper targeting and function of this V-ATPase subunit both in vitro and in vivo in Drosophila melanogaster. We conclude that endo-lysosomal dysfunction in PSEN(-/-) cells is not a consequence of failed N-glycosylation of V0a1, or compromised lysosomal acidification. Instead, lysosomal calcium storage/release is significantly altered in PSEN(-/-) cells and neurons, thus providing an alternative hypothesis that accounts for the impaired lysosomal fusion capacity and accumulation of endomembranes that accompanies PSEN deficiency.
Collapse
Affiliation(s)
- Katrijn Coen
- Department of Human Genetics, VIB Center for the Biology of Disease, Leuven, Belgium
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Amyloid precursor protein (APP) traffics from the cell surface via endosomes for amyloid β (Aβ) production in the trans-Golgi network. Proc Natl Acad Sci U S A 2012; 109:E2077-82. [PMID: 22711829 DOI: 10.1073/pnas.1208635109] [Citation(s) in RCA: 183] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Amyloid precursor protein (APP) is processed sequentially by the β-site APP cleaving enzyme and γ-secretase to generate amyloid β (Aβ) peptides, one of the hallmarks of Alzheimer's disease. The intracellular location of Aβ production-endosomes or the trans-Golgi network (TGN)-remains uncertain. We investigated the role of different postendocytic trafficking events in Aβ(40) production using an RNAi approach. Depletion of Hrs and Tsg101, acting early in the multivesicular body pathway, retained APP in early endosomes and reduced Aβ(40) production. Conversely, depletion of CHMP6 and VPS4, acting late in the pathway, rerouted endosomal APP to the TGN for enhanced APP processing. We found that VPS35 (retromer)-mediated APP recycling to the TGN was required for efficient Aβ(40) production. An interruption of the bidirectional trafficking of APP between the TGN and endosomes, particularly retromer-mediated retrieval of APP from early endosomes to the TGN, resulted in the accumulation of endocytosed APP in early endosomes with reduced APP processing. These data suggest that Aβ(40) is generated predominantly in the TGN, relying on an endocytosed pool of APP recycled from early endosomes to the TGN.
Collapse
|
38
|
Dong C, Nichols CD, Guo J, Huang W, Lambert NA, Wu G. A triple arg motif mediates α(2B)-adrenergic receptor interaction with Sec24C/D and export. Traffic 2012; 13:857-68. [PMID: 22404651 DOI: 10.1111/j.1600-0854.2012.01351.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 03/07/2012] [Accepted: 03/09/2012] [Indexed: 12/28/2022]
Abstract
Recent studies have demonstrated that cargo exit from the endoplasmic reticulum (ER) may be directed by ER export motifs recognized by components of the coat protein II (COPII) vesicles. However, little is known about ER export motifs and vesicle targeting of the G protein-coupled receptor (GPCR) superfamily. Here, we have demonstrated that a triple Arg (3R) motif in the third intracellular loop functions as a novel ER export signal for α(2B)-adrenergic receptor (α(2B)-AR). The 3R motif mediates α(2B)-AR interaction with Sec24C/D and modulates ER exit, cell surface transport and function of α(2B)-AR. Furthermore, export function of the 3R motif is independent of its position within α(2B)-AR and can be conferred to CD8 glycoprotein. These data provide the first evidence implicating that export of GPCRs is controlled by code-directed interactions with selective components of the COPII transport machinery.
Collapse
Affiliation(s)
- Chunmin Dong
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Health Sciences Center, 1901 Perdido St, New Orleans, LA 70112, USA
| | | | | | | | | | | |
Collapse
|
39
|
Kim SD, Pahuja KB, Ravazzola M, Yoon J, Boyadjiev SA, Hammamoto S, Schekman R, Orci L, Kim J. The [corrected] SEC23-SEC31 [corrected] interface plays critical role for export of procollagen from the endoplasmic reticulum. J Biol Chem 2012; 287:10134-10144. [PMID: 22298774 DOI: 10.1074/jbc.m111.283382] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
COPII proteins are essential for exporting most cargo molecules from the endoplasmic reticulum. The membrane-facing surface of the COPII proteins (especially SEC23-SEC24) interacts directly or indirectly with the cargo molecules destined for exit. As we characterized the SEC23A mutations at the SEC31 binding site identified from patients with cranio-lenticulo-sutural dysplasia, we discovered that the SEC23-SEC31 interface can also influence cargo selection. Remarkably, M702V SEC23A does not compromise COPII assembly, vesicle size, and packaging of cargo molecules into COPII vesicles that we have tested but induces accumulation of procollagen in the endoplasmic reticulum when expressed in normal fibroblasts. We observed that M702V SEC23A activates SAR1B GTPase more than wild-type SEC23A when SEC13-SEC31 is present, indicating that M702V SEC23A causes premature dissociation of COPII from the membrane. Our results indicate that a longer stay of COPII proteins on the membrane is required to cargo procollagen than other molecules and suggest that the SEC23-SEC31 interface plays a critical role in capturing various cargo molecules.
Collapse
Affiliation(s)
- Sun-Don Kim
- Section of Genetics, Department of Pediatrics, University of California Davis Medical Center, Sacramento, California 95817
| | - Kanika Bajaj Pahuja
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California Berkeley, Berkeley, California 94720, and
| | - Mariella Ravazzola
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, 1211 Geneva 4, Switzerland
| | - Joonsik Yoon
- Section of Genetics, Department of Pediatrics, University of California Davis Medical Center, Sacramento, California 95817
| | - Simeon A Boyadjiev
- Section of Genetics, Department of Pediatrics, University of California Davis Medical Center, Sacramento, California 95817
| | - Susan Hammamoto
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California Berkeley, Berkeley, California 94720, and
| | - Randy Schekman
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California Berkeley, Berkeley, California 94720, and
| | - Lelio Orci
- Department of Cell Physiology and Metabolism, University of Geneva Medical Center, 1211 Geneva 4, Switzerland
| | - Jinoh Kim
- Section of Genetics, Department of Pediatrics, University of California Davis Medical Center, Sacramento, California 95817,.
| |
Collapse
|
40
|
Fromme JC, Kim J. A rapid and quantitative coat protein complex II vesicle formation assay using luciferase reporters. Anal Biochem 2011; 421:482-8. [PMID: 22244805 DOI: 10.1016/j.ab.2011.12.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2011] [Revised: 12/01/2011] [Accepted: 12/16/2011] [Indexed: 11/19/2022]
Abstract
The majority of protein export from the endoplasmic reticulum (ER) is facilitated by coat protein complex II (COPII). The COPII proteins deform the ER membrane into vesicles at the ER exit sites. During the vesicle formation step, the COPII proteins load cargo molecules into the vesicles. Formation of COPII vesicles has been reconstituted in vitro in yeast and in mammalian systems. These in vitro COPII vesicle formation assays involve incubation of microsomal membranes and purified COPII proteins with nucleotides. COPII vesicles are separated from the microsomes by differential centrifugation. Interestingly, the efficiency of the COPII vesicle formation with purified recombinant mammalian COPII proteins is lower than that with cytosol, suggesting that an additional cytosolic factor(s) is involved in this process. Indeed, other studies have also implicated additional factors. To facilitate biochemical identification of such regulators, a rapid and quantitative COPII vesicle formation assay is necessary because the current assay is lengthy. To expedite this assay, we generated luciferase reporter constructs. The reporter proteins were packaged into COPII vesicles and yielded quantifiable luminescent signals, resulting in a rapid and quantitative COPII vesicle formation assay.
Collapse
Affiliation(s)
- J Chris Fromme
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | | |
Collapse
|
41
|
Wiley JC, Pettan-Brewer C, Ladiges WC. Phenylbutyric acid reduces amyloid plaques and rescues cognitive behavior in AD transgenic mice. Aging Cell 2011; 10:418-28. [PMID: 21272191 DOI: 10.1111/j.1474-9726.2011.00680.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Trafficking through the secretory pathway is known to regulate the maturation of the APP-cleaving secretases and APP proteolysis. The coupling of stress signaling and pathological deterioration of the brain in Alzheimer's disease (AD) supports a mechanistic connection between endoplasmic reticulum (ER) stress and neurodegeneration. Consequently, small molecular chaperones, which promote protein folding and minimize ER stress, might be effective in delaying or attenuating the deleterious progression of AD. We tested this hypothesis by treating APPswePS1delta9 AD transgenic mice with the molecular chaperone phenylbutyric acid (PBA) for 14 months at a dose of 1 mg PBA g(-1) of body weight in the drinking water. Phenylbutyric acid treatment increased secretase-mediated APP cleavage, but was not associated with any increase in amyloid biosynthesis. The PBA-treated AD transgenic mice had significantly decreased incidence and size of amyloid plaques throughout the cortex and hippocampus. There was no change in total amyloid levels suggesting that PBA modifies amyloid aggregation or pathogenesis independently of biogenesis. The decrease in amyloid plaques was paralleled by increased memory retention, as PBA treatment facilitated cognitive performance in a spatial memory task in both wild-type and AD transgenic mice. The molecular mechanism underlying the cognitive facilitation of PBA is not clear; however, increased levels of both metabotropic and ionotropic glutamate receptors, as well as ADAM10 and TACE, were observed in the cortex and hippocampus of PBA-treated mice. The data suggest that PBA ameliorates the cognitive and pathological features of AD and supports the investigation of PBA as a therapeutic for AD.
Collapse
Affiliation(s)
- Jesse C Wiley
- Department of Comparative Medicine, University of Washington School of Medicine, Seattle, USA
| | | | | |
Collapse
|
42
|
Abstract
George Palade, a founding father of cell biology and of the American Society for Cell Biology (ASCB), established the ultrastructural framework for an analysis of how proteins are secreted and membranes are assembled in eukaryotic cells. His vision inspired a generation of investigators to probe the molecular mechanisms of protein transport. My laboratory has dissected these pathways with complementary genetic and biochemical approaches. Peter Novick, one of my first graduate students, isolated secretion mutants of Saccharomyces cerevisiae, and through cytological analysis of single and double mutants and molecular cloning of the corresponding SEC genes, we established that yeast cells use a secretory pathway fundamentally conserved in all eukaryotes. A biochemical reaction that recapitulates the first half of the secretory pathway was used to characterize Sec proteins that comprise the polypeptide translocation channel in the endoplasmic reticulum (ER) membrane (Sec61) and the cytoplasmic coat protein complex (COPII) that captures cargo proteins into transport vesicles that bud from the ER.
Collapse
Affiliation(s)
- Randy Schekman
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California-Berkeley, Berkeley, CA 94720, USA.
| |
Collapse
|
43
|
De Strooper B, Annaert W. Novel Research Horizons for Presenilins and γ-Secretases in Cell Biology and Disease. Annu Rev Cell Dev Biol 2010; 26:235-60. [DOI: 10.1146/annurev-cellbio-100109-104117] [Citation(s) in RCA: 199] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Bart De Strooper
- Center for Human Genetics, Katholieke Universiteit Leuven, and Department for Molecular and Developmental Genetics, VIB, Leuven, Belgium; ,
| | - Wim Annaert
- Center for Human Genetics, Katholieke Universiteit Leuven, and Department for Molecular and Developmental Genetics, VIB, Leuven, Belgium; ,
| |
Collapse
|
44
|
Gong P, Vetrivel KS, Nguyen PD, Meckler X, Cheng H, Kounnas MZ, Wagner SL, Parent AT, Thinakaran G. Mutation analysis of the presenilin 1 N-terminal domain reveals a broad spectrum of gamma-secretase activity toward amyloid precursor protein and other substrates. J Biol Chem 2010; 285:38042-52. [PMID: 20921220 DOI: 10.1074/jbc.m110.132613] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The γ-secretase protein complex executes the intramembrane proteolysis of amyloid precursor protein (APP), which releases Alzheimer disease β-amyloid peptide. In addition to APP, γ-secretase also cleaves several other type I membrane protein substrates including Notch1 and N-cadherin. γ-Secretase is made of four integral transmembrane protein subunits: presenilin (PS), nicastrin, APH1, and PEN2. Multiple lines of evidence indicate that a heteromer of PS-derived N- and C-terminal fragments functions as the catalytic subunit of γ-secretase. Only limited information is available on the domains within each subunit involved in the recognition and recruitment of diverse substrates and the transfer of substrates to the catalytic site. Here, we performed mutagenesis of two domains of PS1, namely the first luminal loop domain (LL1) and the second transmembrane domain (TM2), and analyzed PS1 endoproteolysis as well as the catalytic activities of PS1 toward APP, Notch, and N-cadherin. Our results show that distinct residues within LL1 and TM2 domains as well as the length of the LL1 domain are critical for PS1 endoproteolysis, but not for PS1 complex formation with nicastrin, APH1, and PEN2. Furthermore, our experimental PS1 mutants formed γ-secretase complexes with distinct catalytic properties toward the three substrates examined in this study; however, the mutations did not affect PS1 interaction with the substrates. We conclude that the N-terminal LL1 and TM2 domains are critical for PS1 endoproteolysis and the coordination between the putative substrate-docking site and the catalytic core of the γ-secretase.
Collapse
Affiliation(s)
- Ping Gong
- Department of Neurobiology, University of Chicago, Chicago, Illinois 60637, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
De Strooper B. Proteases and Proteolysis in Alzheimer Disease: A Multifactorial View on the Disease Process. Physiol Rev 2010; 90:465-94. [DOI: 10.1152/physrev.00023.2009] [Citation(s) in RCA: 328] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Alzheimer disease is characterized by the accumulation of abnormally folded protein fragments, i.e., amyloid beta peptide (Aβ) and tau that precipitate in amyloid plaques and neuronal tangles, respectively. In this review we discuss the complicated proteolytic pathways that are responsible for the generation and clearance of these fragments, and how disturbances in these pathways interact and provide a background for a novel understanding of Alzheimer disease as a multifactorial disorder. Recent insights evolve from the static view that the morphologically defined plaques and tangles are disease driving towards a more dynamic, biochemical view in which the intermediary soluble Aβ oligomers and soluble tau fragments are considered as the main mediators of neurotoxicity. The relevance of proteolytic pathways, centered on the generation and clearance of toxic Aβ, on the cleavage and nucleation of tau, and on the general proteostasis of the neurons, then becomes obvious. Blocking or stimulating these pathways provide, or have the potential to provide, interesting drug targets, which raises the hope that we will be able to provide a cure for this dreadful disorder.
Collapse
Affiliation(s)
- Bart De Strooper
- Center for Human Genetics, K.U.Leuven and Department for Molecular and Developmental Genetics, VIB, Leuven, Belgium
| |
Collapse
|
46
|
Wiley JC, Meabon JS, Frankowski H, Smith EA, Schecterson LC, Bothwell M, Ladiges WC. Phenylbutyric acid rescues endoplasmic reticulum stress-induced suppression of APP proteolysis and prevents apoptosis in neuronal cells. PLoS One 2010; 5:e9135. [PMID: 20161760 PMCID: PMC2817752 DOI: 10.1371/journal.pone.0009135] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Accepted: 01/19/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The familial and sporadic forms of Alzheimer's disease (AD) have an identical pathology with a severe disparity in the time of onset [1]. The pathological similarity suggests that epigenetic processes may phenocopy the Familial Alzheimer's disease (FAD) mutations within sporadic AD. Numerous groups have demonstrated that FAD mutations in presenilin result in 'loss of function' of gamma-secretase mediated APP cleavage [2], [3], [4], [5]. Accordingly, ER stress is prominent within the pathologically impacted brain regions in AD patients [6] and is reported to inhibit APP trafficking through the secretory pathway [7], [8]. As the maturation of APP and the cleaving secretases requires trafficking through the secretory pathway [9], [10], [11], we hypothesized that ER stress may block trafficking requisite for normal levels of APP cleavage and that the small molecular chaperone 4-phenylbutyrate (PBA) may rescue the proteolytic deficit. METHODOLOGY/PRINCIPAL FINDINGS The APP-Gal4VP16/Gal4-reporter screen was stably incorporated into neuroblastoma cells in order to assay gamma-secretase mediated APP proteolysis under normal and pharmacologically induced ER stress conditions. Three unrelated pharmacological agents (tunicamycin, thapsigargin and brefeldin A) all repressed APP proteolysis in parallel with activation of unfolded protein response (UPR) signaling-a biochemical marker of ER stress. Co-treatment of the gamma-secretase reporter cells with PBA blocked the repressive effects of tunicamycin and thapsigargin upon APP proteolysis, UPR activation, and apoptosis. In unstressed cells, PBA stimulated gamma-secretase mediated cleavage of APP by 8-10 fold, in the absence of any significant effects upon amyloid production, by promoting APP trafficking through the secretory pathway and the stimulation of the non-pathogenic alpha/gamma-cleavage. CONCLUSIONS/SIGNIFICANCE ER stress represses gamma-secretase mediated APP proteolysis, which replicates some of the proteolytic deficits associated with the FAD mutations. The small molecular chaperone PBA can reverse ER stress induced effects upon APP proteolysis, trafficking and cellular viability. Pharmaceutical agents, such as PBA, that stimulate alpha/gamma-cleavage of APP by modifying intracellular trafficking should be explored as AD therapeutics.
Collapse
Affiliation(s)
- Jesse C Wiley
- Department of Comparative Medicine, University of Washington, Seattle, Washington, United States of America.
| | | | | | | | | | | | | |
Collapse
|
47
|
Sec24b selectively sorts Vangl2 to regulate planar cell polarity during neural tube closure. Nat Cell Biol 2009; 12:41-6; sup pp 1-8. [PMID: 19966784 PMCID: PMC2823131 DOI: 10.1038/ncb2002] [Citation(s) in RCA: 168] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 11/16/2009] [Indexed: 01/02/2023]
Abstract
Craniorachischisis is a rare but severe birth defect that results in a completely open neural tube. Mouse mutants in planar cell polarity (PCP) signalling components have deficits in the morphological movements of convergent extension that result in craniorachischisis. Using a forward genetic screen in mice, we identified Sec24b, a cargo-sorting member of the core complex of the endoplasmic reticulum (ER)-to-Golgi transport vesicle COPII, as critical for neural tube closure. Sec24bY613 mutant mice exhibit craniorachischisis, deficiencies in convergent extension and other PCP-related phenotypes. Vangl2, a key component of the PCP-signalling pathway critical for convergent extension, is selectively sorted into COPII vesicles by Sec24b. Moreover, Sec24bY613 genetically interacts with a loss-of-function Vangl2 allele (Vangl2LP), causing a marked increase in the prevalence of spina bifida. Interestingly, the Vangl2 looptail point mutants Vangl2D255E and Vangl2S464N, known to cause defects in convergent extension, fail to sort into COPII vesicles and are trapped in the ER. Thus, during COPII vesicle formation, Sec24b shows cargo specificity for a core PCP component, Vangl2, of which proper ER-to-Golgi transport is essential for the establishment of PCP, convergent extension and closure of the neural tube.
Collapse
|
48
|
Nielsen AL. The coat protein complex II, COPII, protein Sec13 directly interacts with presenilin-1. Biochem Biophys Res Commun 2009; 388:571-5. [DOI: 10.1016/j.bbrc.2009.08.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 08/08/2009] [Indexed: 11/25/2022]
|
49
|
Suga K, Saito A, Tomiyama T, Mori H, Akagawa K. The Syntaxin 5 Isoforms Syx5 and Syx5L have Distinct Effects on the Processing of β-amyloid Precursor Protein. ACTA ACUST UNITED AC 2009; 146:905-15. [DOI: 10.1093/jb/mvp138] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
50
|
Hayashi I, Takatori S, Urano Y, Iwanari H, Isoo N, Osawa S, Fukuda MA, Kodama T, Hamakubo T, Li T, Wong PC, Tomita T, Iwatsubo T. Single chain variable fragment against nicastrin inhibits the gamma-secretase activity. J Biol Chem 2009; 284:27838-27847. [PMID: 19684016 DOI: 10.1074/jbc.m109.055061] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Gamma-secretase is a membrane protein complex that catalyzes intramembrane proteolysis of a variety of substrates including the amyloid beta precursor protein of Alzheimer disease. Nicastrin (NCT), a single-pass membrane glycoprotein that harbors a large extracellular domain, is an essential component of the gamma-secretase complex. Here we report that overexpression of a single chain variable fragment (scFv) against NCT as an intrabody suppressed the gamma-secretase activity. Biochemical analyses revealed that the scFv disrupted the proper folding and the appropriate glycosyl maturation of the endogenous NCT, which are required for the stability of the gamma-secretase complex and the intrinsic proteolytic activity, respectively, implicating the dual role of NCT in the gamma-secretase complex. Our results also highlight the importance of the calnexin cycle in the functional maturation of the gamma-secretase complex. The engineered intrabodies may serve as rationally designed, molecular targeting tools for the discovery of novel actions of the membrane proteins.
Collapse
Affiliation(s)
- Ikuo Hayashi
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Sho Takatori
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yasuomi Urano
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Hiroko Iwanari
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan; Perseus Proteomics, Inc., 4-7-6 Komaba, Meguro-ku, Tokyo 153-0041, Japan
| | - Noriko Isoo
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Satoko Osawa
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Maiko A Fukuda
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tatsuhiko Kodama
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Takao Hamakubo
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Tong Li
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Philip C Wong
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Taisuke Tomita
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Takeshi Iwatsubo
- Department of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Neuropathology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| |
Collapse
|