101
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Liang Y, Sigrist S. Autophagy and proteostasis in the control of synapse aging and disease. Curr Opin Neurobiol 2018; 48:113-121. [DOI: 10.1016/j.conb.2017.12.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 10/25/2017] [Accepted: 12/10/2017] [Indexed: 11/30/2022]
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102
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Banworth MJ, Li G. Consequences of Rab GTPase dysfunction in genetic or acquired human diseases. Small GTPases 2017; 9:158-181. [PMID: 29239692 DOI: 10.1080/21541248.2017.1397833] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Rab GTPases are important regulators of intracellular membrane trafficking in eukaryotes. Both activating and inactivating mutations in Rab genes have been identified and implicated in human diseases ranging from neurological disorders to cancer. In addition, altered Rab expression is often associated with disease prognosis. As such, the study of diseases associated with Rabs or Rab-interacting proteins has shed light on the important role of intracellular membrane trafficking in disease etiology. In this review, we cover recent advances in the field with an emphasis on cellular mechanisms.
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Affiliation(s)
- Marcellus J Banworth
- a Department of Biochemistry and Molecular Biology , University of Oklahoma Health Sciences Center , Oklahoma City , OK , USA
| | - Guangpu Li
- a Department of Biochemistry and Molecular Biology , University of Oklahoma Health Sciences Center , Oklahoma City , OK , USA
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103
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RAB37 interacts directly with ATG5 and promotes autophagosome formation via regulating ATG5-12-16 complex assembly. Cell Death Differ 2017; 25:918-934. [PMID: 29229996 PMCID: PMC5943352 DOI: 10.1038/s41418-017-0023-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 10/24/2017] [Accepted: 10/24/2017] [Indexed: 02/07/2023] Open
Abstract
Intracellular membrane trafficking is essential for eukaryotic cell existence. Here, we show that RAB37 activation through GTP binding recruits ATG5-12 to isolation membrane and promotes autophagosome formation through the ATG5-ATG12-ATG16L1 complex. RAB37 is localized on the isolation membrane. It can bind directly with ATG5 and promotes formation of the ATG5-12-16 complex. Mutation analysis reveals that GTP-bound RAB37 exhibits an enhanced interaction with ATG5-12 and GDP-stabilised mutation impairs the interaction. RAB37 promotes ATG5-12 interaction with ATG16L1, thus facilitates lipidation of LC3B in a GTP-dependent manner to enhance autophagy. Notably, ablation of RAB37 expression affects the complex formation and decreases autophagy, whereas forced RAB37 expression promotes autophagy and also suppresses cell proliferation. Our results demonstrate a role of RAB37 in autophagosome formation through a molecular connection of RAB37, ATG5-12, ATG16L1 up to LC3B, suggesting an organiser role of RAB37 during autophagosomal membrane biogenesis. These findings have broad implications for understanding the role of RAB vesicle transport in autophagy and cancer.
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104
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Lüningschrör P, Binotti B, Dombert B, Heimann P, Perez-Lara A, Slotta C, Thau-Habermann N, R von Collenberg C, Karl F, Damme M, Horowitz A, Maystadt I, Füchtbauer A, Füchtbauer EM, Jablonka S, Blum R, Üçeyler N, Petri S, Kaltschmidt B, Jahn R, Kaltschmidt C, Sendtner M. Plekhg5-regulated autophagy of synaptic vesicles reveals a pathogenic mechanism in motoneuron disease. Nat Commun 2017; 8:678. [PMID: 29084947 PMCID: PMC5662736 DOI: 10.1038/s41467-017-00689-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 07/20/2017] [Indexed: 12/13/2022] Open
Abstract
Autophagy-mediated degradation of synaptic components maintains synaptic homeostasis but also constitutes a mechanism of neurodegeneration. It is unclear how autophagy of synaptic vesicles and components of presynaptic active zones is regulated. Here, we show that Pleckstrin homology containing family member 5 (Plekhg5) modulates autophagy of synaptic vesicles in axon terminals of motoneurons via its function as a guanine exchange factor for Rab26, a small GTPase that specifically directs synaptic vesicles to preautophagosomal structures. Plekhg5 gene inactivation in mice results in a late-onset motoneuron disease, characterized by degeneration of axon terminals. Plekhg5-depleted cultured motoneurons show defective axon growth and impaired autophagy of synaptic vesicles, which can be rescued by constitutively active Rab26. These findings define a mechanism for regulating autophagy in neurons that specifically targets synaptic vesicles. Disruption of this mechanism may contribute to the pathophysiology of several forms of motoneuron disease. Accumulating evidence suggests that disruption of autophagy is associated with neurodegeneration. Here the authors show that Plekhg5 acts as a GEF for Rab26, a small GTPase that promotes the autophagy of synaptic vesicles in neurons; mice lacking Plekgh5 develop late-onset motoneuron degeneration.
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Affiliation(s)
- Patrick Lüningschrör
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078, Würzburg, Germany.,Department of Cell Biology, University of Bielefeld, 33501, Bielefeld, Germany
| | - Beyenech Binotti
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | - Benjamin Dombert
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078, Würzburg, Germany
| | - Peter Heimann
- Department of Cell Biology, University of Bielefeld, 33501, Bielefeld, Germany
| | - Angel Perez-Lara
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | - Carsten Slotta
- Department of Cell Biology, University of Bielefeld, 33501, Bielefeld, Germany
| | | | - Cora R von Collenberg
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078, Würzburg, Germany
| | - Franziska Karl
- Department of Neurology, University Hospital Würzburg, 97078, Würzburg, Germany
| | - Markus Damme
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, 24098, Kiel, Germany
| | - Arie Horowitz
- Cardeza Vascular Biology Center, Departments of Medicine and Cancer Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Isabelle Maystadt
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, 6041, Gosselies, Belgium
| | - Annette Füchtbauer
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus C, Denmark
| | | | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078, Würzburg, Germany
| | - Robert Blum
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078, Würzburg, Germany
| | - Nurcan Üçeyler
- Department of Neurology, University Hospital Würzburg, 97078, Würzburg, Germany
| | - Susanne Petri
- Department of Neurology, Hannover Medical School, 30625, Hannover, Germany.,Integrated Research and Treatment Center Transplantation (IFB-Tx) Hannover, Hannover Medical School, 30625, Hannover, Germany
| | - Barbara Kaltschmidt
- Department of Cell Biology, University of Bielefeld, 33501, Bielefeld, Germany.,Molecular Neurobiology, University of Bielefeld, 33615, Bielefeld, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | | | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Würzburg, 97078, Würzburg, Germany.
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105
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Abstract
Macroautophagy is an intracellular pathway used for targeting of cellular components to the lysosome for their degradation and involves sequestration of cytoplasmic material into autophagosomes formed from a double membrane structure called the phagophore. The nucleation and elongation of the phagophore is tightly regulated by several autophagy-related (ATG) proteins, but also involves vesicular trafficking from different subcellular compartments to the forming autophagosome. Such trafficking must be tightly regulated by various intra- and extracellular signals to respond to different cellular stressors and metabolic states, as well as the nature of the cargo to become degraded. We are only starting to understand the interconnections between different membrane trafficking pathways and macroautophagy. This review will focus on the membrane trafficking machinery found to be involved in delivery of membrane, lipids, and proteins to the forming autophagosome and in the subsequent autophagosome fusion with endolysosomal membranes. The role of RAB proteins and their regulators, as well as coat proteins, vesicle tethers, and SNARE proteins in autophagosome biogenesis and maturation will be discussed.
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106
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Yap CC, Digilio L, McMahon L, Winckler B. The endosomal neuronal proteins Nsg1/NEEP21 and Nsg2/P19 are itinerant, not resident proteins of dendritic endosomes. Sci Rep 2017; 7:10481. [PMID: 28874679 PMCID: PMC5585371 DOI: 10.1038/s41598-017-07667-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 06/29/2017] [Indexed: 12/28/2022] Open
Abstract
Membrane traffic critically regulates most aspects of neuronal function. Neurons express many neuronal-specific proteins that regulate membrane traffic, including the poorly understood small transmembrane proteins neural-specific gene 1 and 2 (Nsg1/NEEP21 and Nsg2/P19). Nsg1 has been implicated in regulating endosomal recycling and sorting of several important neuronal receptors. Nsg2 is largely unstudied. At steady-state, Nsg1 and Nsg2 only partially co-localize with known endosomal compartments, and it was suggested that they mark a neuronal-specific endosome. Since Nsg1 localizes to and functions in the dendritic endosome, we set out to discover how Nsg1 and Nsg2 localization to endosomes is regulated in primary rat hippocampal neurons, using quadruple immunolocalization against endogenous proteins, live imaging of dendritic endosomes, and interference approaches against the endosomal regulators Rab5 and Rab7. In contrast to previous conclusions, we now show that Nsg1 and Nsg2 are not resident endosomal proteins, but traffic rapidly from the cell surface to lysosomes and have a half-life of less than two hours. Their partial co-localization with canonical endosomal markers thus reflects their rapid flux towards degradation rather than specific targeting to a singular compartment. These findings will require rethinking of how this class of endosomal proteins regulates trafficking of much longer-lived receptors.
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Affiliation(s)
- Chan Choo Yap
- Department of Cell Biology, University of Virginia, Charlottesville, VA, 22908, USA
| | - Laura Digilio
- Department of Cell Biology, University of Virginia, Charlottesville, VA, 22908, USA
| | - Lloyd McMahon
- Department of Cell Biology, University of Virginia, Charlottesville, VA, 22908, USA
| | - Bettina Winckler
- Department of Cell Biology, University of Virginia, Charlottesville, VA, 22908, USA.
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107
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Activity-Dependent Degradation of Synaptic Vesicle Proteins Requires Rab35 and the ESCRT Pathway. J Neurosci 2017; 36:8668-86. [PMID: 27535913 DOI: 10.1523/jneurosci.0725-16.2016] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 06/29/2016] [Indexed: 02/06/2023] Open
Abstract
UNLABELLED Synaptic vesicle (SV) pools must maintain a functional repertoire of proteins to efficiently release neurotransmitter. The accumulation of old or damaged proteins on SV membranes is linked to synaptic dysfunction and neurodegeneration. However, despite the importance of SV protein turnover for neuronal health, the molecular mechanisms underlying this process are largely unknown. Here, we have used dissociated rat hippocampal neurons to investigate the pathway for SV protein degradation. We find that neuronal activity drives the degradation of a subset of SV proteins and that the endosomal sorting complex required for transport (ESCRT) machinery and SV-associated GTPase Rab35 are key elements of this use-dependent degradative pathway. Specifically, neuronal activity induces Rab35 activation and binding to the ESCRT-0 protein Hrs, which we have identified as a novel Rab35 effector. These actions recruit the downstream ESCRT machinery to SV pools, thereby initiating SV protein degradation via the ESCRT pathway. Our findings show that the Rab35/ESCRT pathway facilitates the activity-dependent removal of specific proteins from SV pools, thereby maintaining presynaptic protein homeostasis. SIGNIFICANCE STATEMENT Synaptic transmission is mediated by the release of chemical neurotransmitters from synaptic vesicles (SVs). This tightly regulated process requires a functional pool of SVs, necessitating cellular mechanisms for removing old or damaged proteins that could impair SV cycling. Here, we show that a subset of SV proteins is degraded in an activity-dependent manner and that key steps in this degradative pathway are the activation of the small GTPase Rab35 and the subsequent recruitment of the endosomal sorting complex required for transport (ESCRT) machinery to SV pools. Further, we demonstrate that ESCRT-0 component Hrs is an effector of Rab35, thus providing novel mechanistic insight into the coupling of neuronal activity with SV protein degradation and the maintenance of functional SV pools.
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108
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Li H, He B, Liu X, Li J, Liu Q, Dong W, Xu Z, Qian G, Zuo H, Hu C, Qian H, Mao C, Wang G. Regulation on Toll-like Receptor 4 and Cell Barrier Function by Rab26 siRNA-loaded DNA Nanovector in Pulmonary Microvascular Endothelial Cells. Am J Cancer Res 2017; 7:2537-2554. [PMID: 28744333 PMCID: PMC5525755 DOI: 10.7150/thno.17584] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 04/27/2017] [Indexed: 12/26/2022] Open
Abstract
The small GTPase Rab26 is involved in multiple processes, such as vesicle-mediated secretion and autophagy. However, the mechanisms and functions of Rab26 in the human pulmonary microvascular endothelial cells (HPMVECs) are not clear. In this study, we thoroughly investigated the role and novel mechanism of Rab26 in permeability and apoptosis of HPMVECs using a self-assembled Rab26 siRNA loaded DNA Y-motif nanoparticle (siRab26-DYM) and Rab26 adenovirus. We found that siRab26-DYM could be efficiently transfected into HPMVECs in a time- and dose-dependent manner. Importantly, the siRab26-DYM nanovector markedly aggravated the LPS-induced apoptosis and hyper-permeability of HPMVECs by promoting the nuclear translocation of Foxo1, and subsequent activation of Toll-like receptor 4 (TLR4) signal pathway. Overexpression of Rab26 by Rab26 adenoviruses partially inactivated LPS-induced TLR4 signaling pathway, suppressed the cell apoptosis and attenuated the hyperpermeability of HPMVECs. These results suggest that the permeability and apoptosis of HPMVECs can be modulated by manipulating Rab26 derived TLR4 signaling pathway, and that Rab26 can be potential therapeutic target for the treatment of vascular diseases related to endothelial barrier functions.
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109
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Golgi trafficking defects in postnatal microcephaly: The evidence for “Golgipathies”. Prog Neurobiol 2017; 153:46-63. [DOI: 10.1016/j.pneurobio.2017.03.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/22/2017] [Accepted: 03/29/2017] [Indexed: 12/17/2022]
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110
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Gorenberg EL, Chandra SS. The Role of Co-chaperones in Synaptic Proteostasis and Neurodegenerative Disease. Front Neurosci 2017; 11:248. [PMID: 28579939 PMCID: PMC5437171 DOI: 10.3389/fnins.2017.00248] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/18/2017] [Indexed: 12/14/2022] Open
Abstract
Synapses must be preserved throughout an organism's lifespan to allow for normal brain function and behavior. Synapse maintenance is challenging given the long distances between the termini and the cell body, reliance on axonal transport for delivery of newly synthesized presynaptic proteins, and high rates of synaptic vesicle exo- and endocytosis. Hence, synapses rely on efficient proteostasis mechanisms to preserve their structure and function. To this end, the synaptic compartment has specific chaperones to support its functions. Without proper synaptic chaperone activity, local proteostasis imbalances lead to neurotransmission deficits, dismantling of synapses, and neurodegeneration. In this review, we address the roles of four synaptic chaperones in the maintenance of the nerve terminal, as well as their genetic links to neurodegenerative disease. Three of these are Hsp40 co-chaperones (DNAJs): Cysteine String Protein alpha (CSPα; DNAJC5), auxilin (DNAJC6), and Receptor-Mediated Endocytosis 8 (RME-8; DNAJC13). These co-chaperones contain a conserved J domain through which they form a complex with heat shock cognate 70 (Hsc70), enhancing the chaperone's ATPase activity. CSPα is a synaptic vesicle protein known to chaperone the t-SNARE SNAP-25 and the endocytic GTPase dynamin-1, thereby regulating synaptic vesicle exocytosis and endocytosis. Auxilin binds assembled clathrin cages, and through its interactions with Hsc70 leads to the uncoating of clathrin-coated vesicles, a process necessary for the regeneration of synaptic vesicles. RME-8 is a co-chaperone on endosomes and may have a role in clathrin-coated vesicle endocytosis on this organelle. These three co-chaperones maintain client function by preserving folding and assembly to prevent client aggregation, but they do not break down aggregates that have already formed. The fourth synaptic chaperone we will discuss is Heat shock protein 110 (Hsp110), which interacts with Hsc70, DNAJAs, and DNAJBs to constitute a disaggregase. Hsp110-related disaggregase activity is present at the synapse and is known to protect against aggregation of proteins such as α-synuclein. Congruent with their importance in the nervous system, mutations of these co-chaperones lead to familial neurodegenerative disease. CSPα mutations cause adult neuronal ceroid lipofuscinosis, while auxilin mutations result in early-onset Parkinson's disease, demonstrating their significance in preservation of the nervous system.
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Affiliation(s)
- Erica L Gorenberg
- Interdepartmental Neuroscience Program, Yale UniversityNew Haven, CT, United States
| | - Sreeganga S Chandra
- Department of Neurology, Yale UniversityNew Haven, CT, United States.,Department of Neuroscience, Yale UniversityNew Haven, CT, United States
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111
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Vijayan V, Verstreken P. Autophagy in the presynaptic compartment in health and disease. J Cell Biol 2017; 216:1895-1906. [PMID: 28515275 PMCID: PMC5496617 DOI: 10.1083/jcb.201611113] [Citation(s) in RCA: 127] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/30/2017] [Accepted: 04/25/2017] [Indexed: 12/25/2022] Open
Abstract
Vijayan and Verstreken review the process of autophagy in the synapse and the role of autophagy in maintaining neuronal function. Synapses are functionally distinct neuronal compartments that are critical for brain function, with synaptic dysfunction being an early pathological feature in aging and disease. Given the large number of proteins needed for synaptic function, the proliferation of defective proteins and the subsequent loss of protein homeostasis may be a leading cause of synaptic dysfunction. Autophagic mechanisms are cellular digestion processes that recycle cellular components and contribute to protein homeostasis. Autophagy is important within the nervous system, but its function in specific compartments such as the synapse has been unclear. Evidence from research on both autophagy and synaptic function suggests that there are links between the two and that synaptic homeostasis during aging requires autophagy to regulate protein homeostasis. Exciting new work on autophagy-modulating proteins that are enriched at the synapse has begun to link autophagy to synapses and synaptic dysfunction in disease. A better understanding of these links will help us harness the potential therapeutic benefits of autophagy in combating age-related disorders of the nervous system.
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Affiliation(s)
- Vinoy Vijayan
- Department of Neurosciences, Katholieke University Leuven, 3000 Leuven, Belgium .,Leuven Institute for Neurodegenerative Disease, Katholieke University Leuven, 3000 Leuven, Belgium.,VIB Center for Brain and Disease Research, 3000 Leuven, Belgium
| | - Patrik Verstreken
- Department of Neurosciences, Katholieke University Leuven, 3000 Leuven, Belgium.,Leuven Institute for Neurodegenerative Disease, Katholieke University Leuven, 3000 Leuven, Belgium.,VIB Center for Brain and Disease Research, 3000 Leuven, Belgium
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112
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Abstract
Maintaining synaptic integrity and function depends on the continuous removal and degradation of aged or damaged proteins. Synaptic protein degradation has received considerable attention in the context of synaptic plasticity and growing interest in relation to neurodegenerative and other disorders. Conversely, less attention has been given to constitutive, ongoing synaptic protein degradation and the roles canonical degradation pathways play in these processes. Here we briefly review recent progress on this topic and new experimental approaches which have expedited such progress and highlight several emerging principles. These include the realization that synaptic proteins typically have unusually long lifetimes, as might be expected from the remote locations of most synaptic sites; the possibility that degradation pathways can change with time from synthesis, cellular context, and physiological input; and that degradation pathways, other than ubiquitin-proteasomal-mediated degradation, might play key roles in constitutive protein degradation at synaptic sites. Finally, we point to the importance of careful experimental design and sufficiently sensitive techniques for studying synaptic protein degradation, which bring into account their slow turnover rates and complex life cycles.
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Affiliation(s)
- Laurie D Cohen
- Technion Faculty of Medicine, Rappaport Institute and Network Biology Research Laboratories, Technion City, Haifa, 32000, Israel
| | - Noam E Ziv
- Technion Faculty of Medicine, Rappaport Institute and Network Biology Research Laboratories, Technion City, Haifa, 32000, Israel
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113
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Abstract
Neurons are highly polarized cells that exhibit one of the more complex morphology and function. Neuronal intracellular trafficking plays a key role in dictating the directionality and specificity of vesicle formation, transport and fusion, allowing the transmission of information in sophisticate cellular network. Thus, the integrity of protein trafficking and spatial organization is especially important in neuronal cells. RAB proteins, small monomeric GTPases belonging to the RAS superfamily, spatially and temporally orchestrate specific vesicular trafficking steps. In this review we summarise the known roles of RAB GTPases involved in the maintenance of neuronal vesicular trafficking in the central nervous system. In particular, we discriminate the axonal pre-synaptic trafficking and dendritic post-synaptic trafficking, to better underlie how a correct orchestration of vesicle movement is necessary to maintain neuronal polarity and then, to permit an accurate architecture and functionality of synaptic activity.
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Affiliation(s)
- Maria Lidia Mignogna
- a Molecular Genetics of Intellectual Disabilities Unit, Division of Neuroscience at IRCCS San Raffaele Scientific Institute , Milan , Italy
| | - Patrizia D'Adamo
- a Molecular Genetics of Intellectual Disabilities Unit, Division of Neuroscience at IRCCS San Raffaele Scientific Institute , Milan , Italy
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114
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Up-regulation of the active form of small GTPase Rab13 promotes macroautophagy in vascular endothelial cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:613-624. [DOI: 10.1016/j.bbamcr.2017.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/21/2016] [Accepted: 01/06/2017] [Indexed: 12/25/2022]
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115
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Neefjes J, Jongsma MML, Berlin I. Stop or Go? Endosome Positioning in the Establishment of Compartment Architecture, Dynamics, and Function. Trends Cell Biol 2017; 27:580-594. [PMID: 28363667 DOI: 10.1016/j.tcb.2017.03.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/03/2017] [Accepted: 03/06/2017] [Indexed: 02/03/2023]
Abstract
The endosomal system constitutes a key negotiator between the environment of a cell and its internal affairs. Comprised of a complex membranous network, wherein each vesicle can in principle move autonomously throughout the cell, the endosomal system operates as a coherent unit to optimally face external challenges and maintain homeostasis. Our appreciation of how individual endosomes are controlled in time and space to best serve their collective purpose has evolved dramatically in recent years. In light of these efforts, the endoplasmic reticulum (ER) - with its expanse of membranes permeating the cytoplasmic space - has emerged as a potent spatiotemporal organizer of endosome biology. We review the latest advances in our understanding of the mechanisms underpinning endosomal transport and positioning, with emphasis on the contributions from the ER, and offer a perspective on how the interplay between these aspects shapes the architecture and dynamics of the endosomal system and drives its myriad cellular functions.
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Affiliation(s)
- Jacques Neefjes
- Department of Chemical Immunology, Leiden University Medical Center (LUMC), Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Marlieke M L Jongsma
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center (AMC)/Universiteit van Amsterdam (UvA), Plesmanlaan 125, 1066 CX Amsterdam, The Netherlands
| | - Ilana Berlin
- Department of Chemical Immunology, Leiden University Medical Center (LUMC), Einthovenweg 20, 2333 ZC Leiden, The Netherlands.
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116
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Wang YC, Lauwers E, Verstreken P. Presynaptic protein homeostasis and neuronal function. Curr Opin Genet Dev 2017; 44:38-46. [PMID: 28213157 DOI: 10.1016/j.gde.2017.01.015] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 01/30/2017] [Indexed: 01/15/2023]
Abstract
Proteome integrity is maintained by a coordinated network of molecular chaperones, by protein degradation machineries and by their regulators. Numerous human pathologies are considered as diseases of compromised protein homeostasis (proteostasis), including neurodegeneration. These are characterized by the accumulation of neuronal protein aggregates and by synaptic defects followed by loss of connectivity and cell death. While this suggests that synaptic terminals are particularly sensitive to proteostasis imbalance, our understanding of protein turnover mechanisms and regulation at the synapse remains limited. Recent reports show that different proteolytic pathways act at synapses, including several forms of autophagy. The role of chaperones in controlling the balance between synaptic protein refolding and degradation and how this complex network regulates neuronal function also begins to be unraveled.
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Affiliation(s)
- Yu-Chun Wang
- KU Leuven, Department of Neurosciences, Leuven Institute for Neurodegenerative Disease (LIND), Herestraat 49, bus 602, 3000 Leuven, Belgium; VIB Center for Brain & Disease Research, Herestraat 49, bus 602, 3000 Leuven, Belgium
| | - Elsa Lauwers
- KU Leuven, Department of Neurosciences, Leuven Institute for Neurodegenerative Disease (LIND), Herestraat 49, bus 602, 3000 Leuven, Belgium; VIB Center for Brain & Disease Research, Herestraat 49, bus 602, 3000 Leuven, Belgium.
| | - Patrik Verstreken
- KU Leuven, Department of Neurosciences, Leuven Institute for Neurodegenerative Disease (LIND), Herestraat 49, bus 602, 3000 Leuven, Belgium; VIB Center for Brain & Disease Research, Herestraat 49, bus 602, 3000 Leuven, Belgium.
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117
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A single transcription factor is sufficient to induce and maintain secretory cell architecture. Genes Dev 2017; 31:154-171. [PMID: 28174210 PMCID: PMC5322730 DOI: 10.1101/gad.285684.116] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 01/13/2017] [Indexed: 01/02/2023]
Abstract
Here, Lo et al. demonstrate that cell architecture can be controlled by a developmentally regulated transcriptional program independent of the program that specifies cell identity. They show that MIST1 (BHLHA15) is a “scaling factor” that universally establishes secretory morphology in cells that perform regulated secretion, and targeted deletion of MIST1 causes dismantling of the secretory apparatus of diverse exocrine cells. We hypothesized that basic helix–loop–helix (bHLH) MIST1 (BHLHA15) is a “scaling factor” that universally establishes secretory morphology in cells that perform regulated secretion. Here, we show that targeted deletion of MIST1 caused dismantling of the secretory apparatus of diverse exocrine cells. Parietal cells (PCs), whose function is to pump acid into the stomach, normally lack MIST1 and do not perform regulated secretion. Forced expression of MIST1 in PCs caused them to expand their apical cytoplasm, rearrange mitochondrial/lysosome trafficking, and generate large secretory granules. Mist1 induced a cohort of genes regulated by MIST1 in multiple organs but did not affect PC function. MIST1 bound CATATG/CAGCTG E boxes in the first intron of genes that regulate autophagosome/lysosomal degradation, mitochondrial trafficking, and amino acid metabolism. Similar alterations in cell architecture and gene expression were also caused by ectopically inducing MIST1 in vivo in hepatocytes. Thus, MIST1 is a scaling factor necessary and sufficient by itself to induce and maintain secretory cell architecture. Our results indicate that, whereas mature cell types in each organ may have unique developmental origins, cells performing similar physiological functions throughout the body share similar transcription factor-mediated architectural “blueprints.”
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118
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Altmann C, Hardt S, Fischer C, Heidler J, Lim HY, Häussler A, Albuquerque B, Zimmer B, Möser C, Behrends C, Koentgen F, Wittig I, Schmidt MH, Clement AM, Deller T, Tegeder I. Progranulin overexpression in sensory neurons attenuates neuropathic pain in mice: Role of autophagy. Neurobiol Dis 2016; 96:294-311. [DOI: 10.1016/j.nbd.2016.09.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 08/26/2016] [Accepted: 09/06/2016] [Indexed: 12/14/2022] Open
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119
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Modes and mechanisms of synaptic vesicle recycling. Curr Opin Neurobiol 2016; 39:17-23. [DOI: 10.1016/j.conb.2016.03.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/02/2016] [Accepted: 03/07/2016] [Indexed: 11/30/2022]
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120
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Stavoe AKH, Hill SE, Hall DH, Colón-Ramos DA. KIF1A/UNC-104 Transports ATG-9 to Regulate Neurodevelopment and Autophagy at Synapses. Dev Cell 2016; 38:171-85. [PMID: 27396362 PMCID: PMC4961624 DOI: 10.1016/j.devcel.2016.06.012] [Citation(s) in RCA: 141] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 05/09/2016] [Accepted: 06/09/2016] [Indexed: 01/12/2023]
Abstract
Autophagy is a cellular degradation process important for neuronal development and survival. Neurons are highly polarized cells in which autophagosome biogenesis is spatially compartmentalized. The mechanisms and physiological importance of this spatial compartmentalization of autophagy in the neuronal development of living animals are not well understood. Here we determine that, in Caenorhabditis elegans neurons, autophagosomes form near synapses and are required for neurodevelopment. We first determine, through unbiased genetic screens and systematic genetic analyses, that autophagy is required cell autonomously for presynaptic assembly and for axon outgrowth dynamics in specific neurons. We observe autophagosome biogenesis in the axon near synapses, and this localization depends on the synaptic vesicle kinesin, KIF1A/UNC-104. KIF1A/UNC-104 coordinates localized autophagosome formation by regulating the transport of the integral membrane autophagy protein, ATG-9. Our findings indicate that autophagy is spatially regulated in neurons through the transport of ATG-9 by KIF1A/UNC-104 to regulate neurodevelopment.
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Affiliation(s)
- Andrea K H Stavoe
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Cell Biology and Neuroscience, Yale University School of Medicine, 295 Congress Avenue, BCMM 436B, New Haven, CT 06536-0812, USA
| | - Sarah E Hill
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Cell Biology and Neuroscience, Yale University School of Medicine, 295 Congress Avenue, BCMM 436B, New Haven, CT 06536-0812, USA
| | - David H Hall
- Center for C. elegans Anatomy, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Daniel A Colón-Ramos
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Departments of Cell Biology and Neuroscience, Yale University School of Medicine, 295 Congress Avenue, BCMM 436B, New Haven, CT 06536-0812, USA; Instituto de Neurobiología, Recinto de Ciencias Médicas, Universidad de Puerto Rico, 201 Boulevard del Valle, San Juan 00901, Puerto Rico.
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121
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Fassio A, Fadda M, Benfenati F. Molecular Machines Determining the Fate of Endocytosed Synaptic Vesicles in Nerve Terminals. Front Synaptic Neurosci 2016; 8:10. [PMID: 27242505 PMCID: PMC4863888 DOI: 10.3389/fnsyn.2016.00010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/18/2016] [Indexed: 11/28/2022] Open
Abstract
The cycle of a synaptic vesicle (SV) within the nerve terminal is a step-by-step journey with the final goal of ensuring the proper synaptic strength under changing environmental conditions. The SV cycle is a precisely regulated membrane traffic event in cells and, because of this, a plethora of membrane-bound and cytosolic proteins are devoted to assist SVs in each step of the journey. The cycling fate of endocytosed SVs determines both the availability for subsequent rounds of release and the lifetime of SVs in the terminal and is therefore crucial for synaptic function and plasticity. Molecular players that determine the destiny of SVs in nerve terminals after a round of exo-endocytosis are largely unknown. Here we review the functional role in SV fate of phosphorylation/dephosphorylation of SV proteins and of small GTPases acting on membrane trafficking at the synapse, as they are emerging as key molecules in determining the recycling route of SVs within the nerve terminal. In particular, we focus on: (i) the cyclin-dependent kinase-5 (cdk5) and calcineurin (CN) control of the recycling pool of SVs; (ii) the role of small GTPases of the Rab and ADP-ribosylation factor (Arf) families in defining the route followed by SV in their nerve terminal cycle. These regulatory proteins together with their synaptic regulators and effectors, are molecular nanomachines mediating homeostatic responses in synaptic plasticity and potential targets of drugs modulating the efficiency of synaptic transmission.
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Affiliation(s)
- Anna Fassio
- Department of Experimental Medicine, University of GenoaGenoa, Italy; Center of Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenova, Italy
| | - Manuela Fadda
- Department of Experimental Medicine, University of Genoa Genoa, Italy
| | - Fabio Benfenati
- Department of Experimental Medicine, University of GenoaGenoa, Italy; Center of Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenova, Italy
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122
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Abstract
The RAB class of small GTPases includes the major regulators of intracellular communication, which are involved in vesicle generation through fusion and fission, and vesicular trafficking. RAB proteins also play an imperative role in neuronal maintenance and survival. Recent studies in the field of neurodegeneration have also highlighted the process of autophagy as being essential for neuronal maintenance. Here we review the emerging roles of RAB proteins in regulating macroautophagy and its impact in the context of neurodegenerative diseases.
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Affiliation(s)
- Navodita Jain
- a Department of Biological Sciences & Bioengineering , Indian Institute of Technology , Kanpur , India
| | - Subramaniam Ganesh
- a Department of Biological Sciences & Bioengineering , Indian Institute of Technology , Kanpur , India
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123
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Yagensky O, Kalantary Dehaghi T, Chua JJE. The Roles of Microtubule-Based Transport at Presynaptic Nerve Terminals. Front Synaptic Neurosci 2016; 8:3. [PMID: 26903856 PMCID: PMC4748046 DOI: 10.3389/fnsyn.2016.00003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 01/29/2016] [Indexed: 01/19/2023] Open
Abstract
Targeted intracellular movement of presynaptic proteins plays important roles during synapse formation and, later, in the homeostatic maintenance of mature synapses. Movement of these proteins, often as vesicular packages, is mediated by motor complexes travelling along intracellular cytoskeletal networks. Presynaptic protein transport by kinesin motors in particular plays important roles during synaptogenesis to bring newly synthesized proteins to establish nascent synaptic sites. Conversely, movement of proteins away from presynaptic sites by Dynein motors enables synapse-nuclear signaling and allows for synaptic renewal through degradation of unwanted or damaged proteins. Remarkably, recent data has indicated that synaptic and protein trafficking machineries can modulate each other's functions. Here, we survey the mechanisms involved in moving presynaptic components to and away from synapses and how this process supports presynaptic function.
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Affiliation(s)
- Oleksandr Yagensky
- Research Group Protein Trafficking in Synaptic Development and Function, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry Göttingen, Germany
| | - Tahere Kalantary Dehaghi
- Research Group Protein Trafficking in Synaptic Development and Function, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry Göttingen, Germany
| | - John Jia En Chua
- Research Group Protein Trafficking in Synaptic Development and Function, Department of Neurobiology, Max-Planck-Institute for Biophysical ChemistryGöttingen, Germany; Interactomics and Intracellular Trafficking Laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, SingaporeSingapore; Neurobiology/Ageing Programme, National University of Singapore, SingaporeSingapore
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124
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Binotti B, Jahn R, Chua JJE. Functions of Rab Proteins at Presynaptic Sites. Cells 2016; 5:E7. [PMID: 26861397 PMCID: PMC4810092 DOI: 10.3390/cells5010007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 02/03/2016] [Indexed: 01/24/2023] Open
Abstract
Presynaptic neurotransmitter release is dominated by the synaptic vesicle (SV) cycle and entails the biogenesis, fusion, recycling, reformation or turnover of synaptic vesicles-a process involving bulk movement of membrane and proteins. As key mediators of membrane trafficking, small GTPases from the Rab family of proteins play critical roles in this process by acting as molecular switches that dynamically interact with and regulate the functions of different sets of macromolecular complexes involved in each stage of the cycle. Importantly, mutations affecting Rabs, and their regulators or effectors have now been identified that are implicated in severe neurological and neurodevelopmental disorders. Here, we summarize the roles and functions of presynaptic Rabs and discuss their involvement in the regulation of presynaptic function.
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Affiliation(s)
- Beyenech Binotti
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen 37077, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen 37077, Germany
| | - John Jia En Chua
- Interactomics and Intracellular Trafficking laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117456, Singapore.
- Neurobiology/Ageing Programme, National University of Singapore, Singapore 117456, Singapore.
- Research Group Protein trafficking in synaptic development and function, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen 37077, Germany.
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125
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Tagliatti E, Fadda M, Falace A, Benfenati F, Fassio A. Arf6 regulates the cycling and the readily releasable pool of synaptic vesicles at hippocampal synapse. eLife 2016; 5. [PMID: 26731518 PMCID: PMC4764570 DOI: 10.7554/elife.10116] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 01/04/2016] [Indexed: 01/29/2023] Open
Abstract
Recycling of synaptic vesicles (SVs) is a fundamental step in the process of neurotransmission. Endocytosed SV can travel directly into the recycling pool or recycle through endosomes but little is known about the molecular actors regulating the switch between these SV recycling routes. ADP ribosylation factor 6 (Arf6) is a small GTPase known to participate in constitutive trafficking between plasma membrane and early endosomes. Here, we have morphologically and functionally investigated Arf6-silenced hippocampal synapses and found an activity dependent accumulation of synaptic endosome-like organelles and increased release-competent docked SVs. These features were phenocopied by pharmacological blockage of Arf6 activation. The data reveal an unexpected role for this small GTPase in reducing the size of the readily releasable pool of SVs and in channeling retrieved SVs toward direct recycling rather than endosomal sorting. We propose that Arf6 acts at the presynapse to define the fate of an endocytosed SV. DOI:http://dx.doi.org/10.7554/eLife.10116.001 Communication between neurons takes place at cell-to-cell contacts called synapses. Each synapse is formed between one neuron that sends the message, and another neuron that receives it. The neuron before the synapse – called the presynaptic neuron – contains packets called synaptic vesicles, which are full of chemical messengers ready to be released upon activity. Accurate communication between neurons relies on the exact composition, and organized trafficking, of the synaptic vesicles when the neuron is active. Synapses also contain bigger structures, called endosomal structures, which may represent an intermediate station in which synaptic vesicle composition is controlled. However, the trafficking of synaptic vesicles through the endosomal structures is poorly understood. Now, Tagliatti, Fadda et al. have revealed that a protein called Arf6 plays an important role in presynaptic neurons. The experiments involved rat neurons grown in the laboratory, and showed that Arf6 controls both the number of synaptic vesicles ready to be released and the trafficking of synaptic vesicles via endosomal structures in active neurons. The next step following on from these findings is to understand how Arf6 exerts its effects and how this protein is regulated in the presynaptic neuron. DOI:http://dx.doi.org/10.7554/eLife.10116.002
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Affiliation(s)
- Erica Tagliatti
- Center of Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy.,Department of Experimental Medicine, University of Genova, Genova, Italy
| | - Manuela Fadda
- Department of Experimental Medicine, University of Genova, Genova, Italy
| | - Antonio Falace
- Department of Experimental Medicine, University of Genova, Genova, Italy
| | - Fabio Benfenati
- Center of Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy.,Department of Experimental Medicine, University of Genova, Genova, Italy
| | - Anna Fassio
- Center of Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genova, Italy.,Department of Experimental Medicine, University of Genova, Genova, Italy
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126
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Khaminets A, Behl C, Dikic I. Ubiquitin-Dependent And Independent Signals In Selective Autophagy. Trends Cell Biol 2015; 26:6-16. [PMID: 26437584 DOI: 10.1016/j.tcb.2015.08.010] [Citation(s) in RCA: 502] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/28/2015] [Accepted: 08/28/2015] [Indexed: 02/06/2023]
Abstract
Selective autophagy regulates the abundance of specific cellular components via a specialized arsenal of factors, termed autophagy receptors, that target protein complexes, aggregates, and whole organelles into lysosomes. Autophagy receptors bind to LC3/GABARAP proteins on phagophore and autophagosome membranes, and recognize signals on cargoes to deliver them to autophagy. Ubiquitin (Ub), a well-known signal for the degradation of polypeptides in the proteasome, also plays an important role in the recognition of cargoes destined for selective autophagy. In addition, a variety of cargoes are committed to selective autophagy pathways by Ub-independent mechanisms employing protein-protein interaction motifs, Ub-like modifiers, and sugar- or lipid-based signals. In this article we summarize Ub-dependent and independent selective autophagy pathways, and discuss regulatory mechanisms and challenges for future studies.
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Affiliation(s)
- Aliaksandr Khaminets
- Institute of Biochemistry II, Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Max-von-Laue-Straße 15, 60438 Frankfurt am Main, Germany
| | - Christian Behl
- Institute of Pathobiochemistry, University Medical Center, Johannes Gutenberg University, Mainz, Germany
| | - Ivan Dikic
- Institute of Biochemistry II, Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Max-von-Laue-Straße 15, 60438 Frankfurt am Main, Germany.
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127
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Shen DN, Zhang LH, Wei EQ, Yang Y. Autophagy in synaptic development, function, and pathology. Neurosci Bull 2015; 31:416-26. [PMID: 26139541 DOI: 10.1007/s12264-015-1536-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 05/30/2015] [Indexed: 01/04/2023] Open
Abstract
In the nervous system, neurons contact each other to form neuronal circuits and drive behavior, relying heavily on synaptic connections. The proper development and growth of synapses allows functional transmission of electrical information between neurons or between neurons and muscle fibers. Defects in synapse-formation or development lead to many diseases. Autophagy, a major determinant of protein turnover, is an essential process that takes place in developing synapses. During the induction of autophagy, proteins and cytoplasmic components are encapsulated in autophagosomes, which fuse with lysosomes to form autolysosomes. The cargoes are subsequently degraded and recycled. However, aberrant autophagic activity may lead to synaptic dysfunction, which is a common pathological characteristic in several disorders. Here, we review the current understanding of autophagy in regulating synaptic development and function. In addition, autophagy-related synaptic dysfunction in human diseases is also summarized.
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Affiliation(s)
- Dan-Na Shen
- Department of Pharmacology, Hangzhou Key Laboratory of Medical Neurobiology, School of Medicine, Hangzhou Normal University, Hangzhou, 310036, China
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