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Wang Y, Zhu Y, Li W, Yan S, Li C, Ma K, Hu M, Du C, Fu L, Sun J, Zhang CX. Synaptotagmin-11 Inhibits Synaptic Vesicle Endocytosis via Endophilin A1. J Neurosci 2023; 43:6230-6248. [PMID: 37474308 PMCID: PMC10490507 DOI: 10.1523/jneurosci.1348-21.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 05/12/2023] [Accepted: 06/02/2023] [Indexed: 07/22/2023] Open
Abstract
Synaptic vesicle (SV) endocytosis is a critical and well-regulated process for the maintenance of neurotransmission. We previously reported that synaptotagmin-11 (Syt11), an essential non-Ca2+-binding Syt associated with brain diseases, inhibits neuronal endocytosis (Wang et al., 2016). Here, we found that Syt11 deficiency caused accelerated SV endocytosis and vesicle recycling under sustained stimulation and led to the abnormal membrane partition of synaptic proteins in mouse hippocampal boutons of either sex. Furthermore, our study revealed that Syt11 has direct but Ca2+-independent binding with endophilin A1 (EndoA1), a membrane curvature sensor and endocytic protein recruiter, with high affinity. EndoA1-knockdown significantly reversed Syt11-KO phenotype, identifying EndoA1 as a main inhibitory target of Syt11 during SV endocytosis. The N-terminus of EndoA1 and the C2B domain of Syt11 were responsible for this interaction. A peptide (amino acids 314-336) derived from the Syt11 C2B efficiently blocked Syt11-EndoA1 binding both in vitro and in vivo Application of this peptide inhibited SV endocytosis in WT hippocampal neurons but not in EndoA1-knockdown neurons. Moreover, intracellular application of this peptide in mouse calyx of Held terminals of either sex effectively hampered both fast and slow SV endocytosis at physiological temperature. We thus propose that Syt11 ensures the precision of protein retrieval during SV endocytosis by inhibiting EndoA1 function at neuronal terminals.SIGNIFICANCE STATEMENT Endocytosis is a key stage of synaptic vesicle (SV) recycling. SV endocytosis retrieves vesicular membrane and protein components precisely to support sustained neurotransmission. However, the molecular mechanisms underlying the regulation of SV endocytosis remain elusive. Here, we reported that Syt11-KO accelerated SV endocytosis and impaired membrane partition of synaptic proteins. EndoA1 was identified as a main inhibitory target of Syt11 during SV endocytosis. Our study reveals a novel inhibitory mechanism of SV endocytosis in preventing hyperactivation of endocytosis, potentially safeguarding the recycling of synaptic proteins during sustained neurotransmission.
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Affiliation(s)
- Yalong Wang
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences; CAS Key Laboratory of Brain Connectome and Manipulation; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, Guangdong 518055, China
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Ying Zhu
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wanru Li
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Shuxin Yan
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Chao Li
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Key Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Kunpeng Ma
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences; CAS Key Laboratory of Brain Connectome and Manipulation; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, Guangdong 518055, China
| | - Meiqin Hu
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109
| | - Cuilian Du
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Lei Fu
- Academy of Pharmacy, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
| | - Jianyuan Sun
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences; CAS Key Laboratory of Brain Connectome and Manipulation; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, Guangdong 518055, China
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Claire Xi Zhang
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Academy of Pharmacy, Xi'an Jiaotong-Liverpool University, Suzhou, Jiangsu 215123, China
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2
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Bademosi AT, Decet M, Kuenen S, Calatayud C, Swerts J, Gallego SF, Schoovaerts N, Karamanou S, Louros N, Martin E, Sibarita JB, Vints K, Gounko NV, Meunier FA, Economou A, Versées W, Rousseau F, Schymkowitz J, Soukup SF, Verstreken P. EndophilinA-dependent coupling between activity-induced calcium influx and synaptic autophagy is disrupted by a Parkinson-risk mutation. Neuron 2023; 111:1402-1422.e13. [PMID: 36827984 PMCID: PMC10166451 DOI: 10.1016/j.neuron.2023.02.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 11/09/2022] [Accepted: 01/31/2023] [Indexed: 02/26/2023]
Abstract
Neuronal activity causes use-dependent decline in protein function. However, it is unclear how this is coupled to local quality control mechanisms. We show in Drosophila that the endocytic protein Endophilin-A (EndoA) connects activity-induced calcium influx to synaptic autophagy and neuronal survival in a Parkinson disease-relevant fashion. Mutations in the disordered loop, including a Parkinson disease-risk mutation, render EndoA insensitive to neuronal stimulation and affect protein dynamics: when EndoA is more flexible, its mobility in membrane nanodomains increases, making it available for autophagosome formation. Conversely, when EndoA is more rigid, its mobility reduces, blocking stimulation-induced autophagy. Balanced stimulation-induced autophagy is required for dopagminergic neuron survival, and a variant in the human ENDOA1 disordered loop conferring risk to Parkinson disease also blocks nanodomain protein mobility and autophagy both in vivo and in human-induced dopaminergic neurons. Thus, we reveal a mechanism that neurons use to connect neuronal activity to local autophagy and that is critical for neuronal survival.
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Affiliation(s)
- Adekunle T Bademosi
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium; Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Marianna Decet
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium
| | - Sabine Kuenen
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium
| | - Carles Calatayud
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium
| | - Jef Swerts
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium
| | - Sandra F Gallego
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium
| | - Nils Schoovaerts
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium
| | - Spyridoula Karamanou
- KU Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Leuven 3000, Belgium
| | - Nikolaos Louros
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Leuven 3000, Belgium
| | - Ella Martin
- VIB-VUB Center for Structural Biology, Brussels 1050, Belgium; Department of Structural Biology Brussels, Vrije Universiteit Brussel, Brussels 1050, Belgium
| | - Jean-Baptiste Sibarita
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, F-33000 Bordeaux, France
| | - Katlijn Vints
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium; VIB Bio Core, KU Leuven, Leuven 3000, Belgium
| | - Natalia V Gounko
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium; VIB Bio Core, KU Leuven, Leuven 3000, Belgium
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia; School of Biomedical Sciences, The University of Queensland, St Lucia Campus, Brisbane, QLD 4072, Australia
| | - Anastassios Economou
- KU Leuven, Department of Microbiology and Immunology, Rega Institute for Medical Research, Leuven 3000, Belgium
| | - Wim Versées
- VIB-VUB Center for Structural Biology, Brussels 1050, Belgium; Department of Structural Biology Brussels, Vrije Universiteit Brussel, Brussels 1050, Belgium
| | - Frederic Rousseau
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Leuven 3000, Belgium
| | - Joost Schymkowitz
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Leuven 3000, Belgium
| | | | - Patrik Verstreken
- VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium; KU Leuven, Department of Neurosciences, Leuven Brain Institute, Mission Lucidity, Leuven 3000, Belgium.
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Chen L, Wang H, Cha S, Li J, Zhang J, Wu J, Guo G, Zhang J. Phosphorylation of Spastin Promotes the Surface Delivery and Synaptic Function of AMPA Receptors. Front Cell Neurosci 2022; 16:809934. [PMID: 35418834 PMCID: PMC8995424 DOI: 10.3389/fncel.2022.809934] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 03/07/2022] [Indexed: 12/14/2022] Open
Abstract
Synaptic plasticity is essential for cognitive functions such as learning and memory. One of the mechanisms involved in synaptic plasticity is the dynamic delivery of AMPA receptors (AMPARs) in and out of synapses. Mutations of SPAST, which encodes SPASTIN, a microtubule-severing protein, are considered the most common cause of hereditary spastic paraparesis (HSP). In some cases, patients with HSP also manifest cognitive impairment. In addition, mice with Spastin depletion exhibit working and associative memory deficits and reduced AMPAR levels. However, the exact effect and molecular mechanism of Spastin on AMPARs trafficking has remained unclear. Here, we report that Spastin interacts with AMPAR, and phosphorylation of Spastin enhances its interaction with AMPAR subunit GluA2. Further study shows that phosphorylation of Spastin can increase AMPAR GluA2 surface expression and the amplitude and frequency of miniature excitatory synaptic currents (mEPSC) in cultured hippocampal neurons. Moreover, phosphorylation of Spastin at Ser210 is crucial for GluA2 surface expression. Phosphorylation of Spastin K353A, which obliterates microtubule-severing activity, also promotes AMPAR GluA2 subunit trafficking to the surface and increases the amplitude and frequency of mEPSCs in cultured neurons. Taken together, our data demonstrate that Spastin phosphorylation promotes the surface delivery of the AMPAR GluA2 subunit independent of microtubule dynamics.
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Affiliation(s)
- Li Chen
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Hanjie Wang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Shuhan Cha
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiong Li
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiaqi Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiaming Wu
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
- Department of Neurosurgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Guoqing Guo
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
- *Correspondence: Guoqing Guo Jifeng Zhang
| | - Jifeng Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
- *Correspondence: Guoqing Guo Jifeng Zhang
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4
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Yapici-Eser H, Koroglu YE, Oztop-Cakmak O, Keskin O, Gursoy A, Gursoy-Ozdemir Y. Neuropsychiatric Symptoms of COVID-19 Explained by SARS-CoV-2 Proteins' Mimicry of Human Protein Interactions. Front Hum Neurosci 2021; 15:656313. [PMID: 33833673 PMCID: PMC8021734 DOI: 10.3389/fnhum.2021.656313] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/23/2021] [Indexed: 12/16/2022] Open
Abstract
The first clinical symptoms focused on the presentation of coronavirus disease 2019 (COVID-19) have been respiratory failure, however, accumulating evidence also points to its presentation with neuropsychiatric symptoms, the exact mechanisms of which are not well known. By using a computational methodology, we aimed to explain the molecular paths of COVID-19 associated neuropsychiatric symptoms, based on the mimicry of the human protein interactions with SARS-CoV-2 proteins. Methods: Available 11 of the 29 SARS-CoV-2 proteins' structures have been extracted from Protein Data Bank. HMI-PRED (Host-Microbe Interaction PREDiction), a recently developed web server for structural PREDiction of protein-protein interactions (PPIs) between host and any microbial species, was used to find the "interface mimicry" through which the microbial proteins hijack host binding surfaces. Classification of the found interactions was conducted using the PANTHER Classification System. Results: Predicted Human-SARS-CoV-2 protein interactions have been extensively compared with the literature. Based on the analysis of the molecular functions, cellular localizations and pathways related to human proteins, SARS-CoV-2 proteins are found to possibly interact with human proteins linked to synaptic vesicle trafficking, endocytosis, axonal transport, neurotransmission, growth factors, mitochondrial and blood-brain barrier elements, in addition to its peripheral interactions with proteins linked to thrombosis, inflammation and metabolic control. Conclusion: SARS-CoV-2-human protein interactions may lead to the development of delirium, psychosis, seizures, encephalitis, stroke, sensory impairments, peripheral nerve diseases, and autoimmune disorders. Our findings are also supported by the previous in vivo and in vitro studies from other viruses. Further in vivo and in vitro studies using the proteins that are pointed here, could pave new targets both for avoiding and reversing neuropsychiatric presentations.
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Affiliation(s)
- Hale Yapici-Eser
- Department of Psychiatry, School of Medicine, Koç University, Istanbul, Turkey
- Research Center for Translational Medicine, Koç University, Istanbul, Turkey
| | - Yunus Emre Koroglu
- Research Center for Translational Medicine, Koç University, Istanbul, Turkey
- Graduate School of Sciences and Engineering, College of Engineering, Koç University, Istanbul, Turkey
| | - Ozgur Oztop-Cakmak
- Research Center for Translational Medicine, Koç University, Istanbul, Turkey
- Department of Neurology, School of Medicine, Koç University, Istanbul, Turkey
| | - Ozlem Keskin
- Research Center for Translational Medicine, Koç University, Istanbul, Turkey
- College of Engineering, Chemical and Biological Engineering, Koç University, Istanbul, Turkey
| | - Attila Gursoy
- Research Center for Translational Medicine, Koç University, Istanbul, Turkey
- Department of Computer Science and Engineering, College of Engineering, Koç University, Istanbul, Turkey
| | - Yasemin Gursoy-Ozdemir
- Research Center for Translational Medicine, Koç University, Istanbul, Turkey
- Department of Neurology, School of Medicine, Koç University, Istanbul, Turkey
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5
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Zhang J, Li J, Yin Y, Li X, Jiang Y, Wang Y, Cha C, Guo G. Collapsin Response Mediator Protein 2 and Endophilin2 Coordinate Regulation of AMPA Receptor GluA1 Subunit Recycling. Front Mol Neurosci 2020; 13:128. [PMID: 32848595 PMCID: PMC7417516 DOI: 10.3389/fnmol.2020.00128] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 06/26/2020] [Indexed: 11/13/2022] Open
Abstract
The dynamic trafficking of AMPA receptors (AMPARs), which enables the endocytosis, recycling, and exocytosis of AMPARs, is crucial for synaptic plasticity. Endophilin2, which directly interacts with the GluA1 subunit of AMPARs, plays an important role in AMPAR endocytosis. Collapsin response mediator protein 2 (CRMP2) promotes the maturation of the dendritic spine and can transfer AMPARs to the membrane. Although the mechanisms of AMPAR endocytosis and exocytosis are well known, the exact molecular mechanisms underlying AMPAR recycling remain unclear. Here, we report a unique interaction between CRMP2 and endophilin2. Our results showed that overexpression of CRMP2 and endophilin2 increased the amplitude and frequency of miniature excitatory synaptic currents (mEPSCs) and modestly enhanced AMPAR levels in hippocampal neurons. Furthermore, the CRMP2 and endophilin2 overexpression phenotype failed to occur when the interaction between these two proteins was inhibited. Further analysis revealed that this interaction was regulated by CRMP2 phosphorylation. The phosphorylation of CRMP2 inhibited its interaction with endophilin2; this was mainly affected by the phosphorylation of Thr514 and Ser518 by glycogen synthase kinase (GSK) 3β. CRMP2 phosphorylation increased degradation and inhibited the surface expression of AMPAR GluA1 subunits in cultured hippocampal neurons. However, the dephosphorylation of CRMP2 inhibited degradation and promoted the surface expression of AMPAR GluA1 subunits in cultured hippocampal neurons. Taken together, our data demonstrated that the interaction between CRMP2 and endophilin2 was conductive to the recycling of AMPA receptor GluA1 subunits in hippocampal neurons.
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Affiliation(s)
- Jifeng Zhang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Jiong Li
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Yichen Yin
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China.,Department of Neurology, Guangzhou Red Cross Hospital, Medical College, Jinan University, Guangzhou, China
| | - Xueling Li
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Yuxin Jiang
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
| | - Yong Wang
- Department of Forensic Science, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Caihui Cha
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China.,Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, China
| | - Guoqing Guo
- Department of Anatomy, Neuroscience Laboratory for Cognitive and Developmental Disorders, Medical College of Jinan University, Guangzhou, China
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6
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Cai Z, Zhu X, Zhang G, Wu F, Lin H, Tan M. Ammonia induces calpain-dependent cleavage of CRMP-2 during neurite degeneration in primary cultured neurons. Aging (Albany NY) 2020; 11:4354-4366. [PMID: 31278888 PMCID: PMC6660054 DOI: 10.18632/aging.102053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 06/19/2019] [Indexed: 01/07/2023]
Abstract
Hyperammonemia in the CNS induces irreversible damages to neurons due to ultimate cell loss. Neurite degeneration, a primary event that leads to neuronal cell death, remains less elucidated especially in hyperammonemia circumstances. Here, we found that the administration of ammonia induced neurite degeneration in cultured cerebellar granule neurons. The resulting altered neuronal morphology, rupture of neurites, and disassembly of the cytoskeleton led to cell death. Calcein and Fluo-4 staining revealed that ammonia induced intracellular calcium dysregulation. Subsequently activated calpain cleaved CRMP-2, a microtubule assembly protein. Pharmacologically inhibition of calpain, but not caspases or GSK-3, suppressed the cleavage of CRMP-2 and reversed neurite degeneration under ammonia treatment. Exposure to ammonia decreased whereas inhibition of calpain restored the amplitude and frequency of miniature excitatory postsynaptic currents. These data suggest a mechanism by which elevated ammonia level may induce neuronal dysfunction via abnormal calcium influx and calpain-dependent CRMP-2 cleavage, leading to abnormal synaptic transmission, cytoskeletal collapse, and neurite degeneration.
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Affiliation(s)
- Zhenbin Cai
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xiaonan Zhu
- Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Guowei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Fengming Wu
- Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Hongsheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Minghui Tan
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, China
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7
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Biochanin A protects against angiotensin II-induced damage of dopaminergic neurons in rats associated with the increased endophilin A2 expression. Behav Pharmacol 2019; 30:700-711. [PMID: 31703032 DOI: 10.1097/fbp.0000000000000515] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The brain renin-angiotensin system plays a vital role in the modulation of the neuroinflammatory responses and the progression of dopaminergic (DA) degeneration. Angiotensin II (Ang II) induces microglia activation via angiotensin II type 1 receptor (AT1R), which in turn affects the function of DA neurons. Endophilin A2 (EPA2) is involved in fast endophilin-mediated endocytosis and quickly endocytoses several G-protein-coupled receptor (GPCR), while AT1R belongs to GPCR family. Therefore, we speculated that EPA2 may modulate microglia activation via endocytosing AT1R. Biochanin A is an O-methylated isoflavone, classified as a kind of phytoestrogen due to its chemical structure that is similar to mammalian estrogens. In this study, we investigated the protective effects of biochanin A on Ang II-induced DA neurons damage in vivo, and molecular mechanisms. The results showed that biochanin A treatment for 7 days attenuated the behavioral dysfunction, inhibited the microglial activation, and prevented DA neuron damage in Ang II-induced rats. Furthermore, biochanin A increased EPA2 expression and decreased the expression of AT1R, gp91phox, p22 phox, NLRP3, ASC, Caspase-1, IL-1β, IL-6, IL-18, and TNF-α. In summary, these results suggest that biochanin A exerts protective effects in Ang II-induced model rats, and the mechanisms may involve inhibition of inflammatory responses, an increase in EPA2 expression and a decrease in AT1R expression.
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8
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Yin Y, Cha C, Wu F, Li J, Li S, Zhu X, Zhang J, Guo G. Endophilin 1 knockdown prevents synaptic dysfunction induced by oligomeric amyloid β. Mol Med Rep 2019; 19:4897-4905. [PMID: 31059028 PMCID: PMC6522965 DOI: 10.3892/mmr.2019.10158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 04/03/2019] [Indexed: 12/18/2022] Open
Abstract
Amyloid β (Aβ) has been reported to have an important role in the cognitive deficits of Alzheimer's disease (AD), as oligomeric Aβ promotes synaptic dysfunction and triggers neuronal death. Recent evidence has associated an endocytosis protein, endophilin 1, with AD, as endophilin 1 levels have been reported to be markedly increased in the AD brain. The increase in endophilin 1 levels in neurons is associated with an increase in the activation of the stress kinase JNK, with subsequent neuronal death. In the present study, whole-cell patch-clamp recording demonstrated that oligomeric Aβ caused synaptic dysfunction and western blotting revealed that endophilin 1 was highly expressed prior to neuronal death of cultured hippocampal neurons. Furthermore, RNA interference and electrophysiological recording techniques in cultured hippocampal neurons demonstrated that knockdown of endophilin 1 prevented synaptic dysfunction induced by Aβ. Thus, a potential role for endophilin 1 in Aβ-induced postsynaptic dysfunction has been identified, indicating a possible direction for the prevention of postsynaptic dysfunction in cognitive impairment and suggesting that endophilin may be a potential target for the clinical treatment of AD.
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Affiliation(s)
- Yichen Yin
- Department of Neurology, Guangzhou Red Cross Hospital, Medical College, Jinan University, Guangzhou, Guangdong 510220, P.R. China
| | - Caihui Cha
- Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, Guangdong 510120, P.R. China
| | - Fengming Wu
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Jiong Li
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Sumei Li
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Xiaonan Zhu
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Jifeng Zhang
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Guoqing Guo
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
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9
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Ji Z, Zhang G, Chen L, Li J, Yang Y, Cha C, Zhang J, Lin H, Guo G. Spastin Interacts with CRMP5 to Promote Neurite Outgrowth by Controlling the Microtubule Dynamics. Dev Neurobiol 2018; 78:1191-1205. [PMID: 30257070 DOI: 10.1002/dneu.22640] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 07/27/2018] [Accepted: 09/07/2018] [Indexed: 12/14/2022]
Abstract
Changing the microtubule dynamics is sufficient to alter the axon and dendrite specification and development. Spastin participates in the growth and regeneration of neurites by severing microtubules into small segments, and collapsin response mediator protein 5 (CRMP5) provides structural support and serves as a track for cargo transport by promoting microtubule polymerization. Nevertheless, how spastin and CRMP5 cooperate to regulate neurite outgrowth by controlling the microtubule dynamics needs to be elucidated. In our present study, spastin interacted with CRMP5 in vitro and in vivo. The binding domains for the spastin and CRMP5 interaction were the N-terminal fragment of spastin (residues 270-328) and the C-terminal fragment of CRMP5 (residues 472-564). Spastin and its truncation mutants, including the microtubule-binding domain (MTBD) and ATPases associated with diverse cellular activities (AAA) domain, were necessary for the severing of microtubules. Furthermore, we demonstrated that microtubule polymerization of CRMP5 interfered with the microtubule-severing function of spastin. Knocking down either spastin or CRMP5 inhibited neurite outgrowth in hippocampal neurons. However, co-transfected spastin and CRMP5 promoted the outgrowth of neurites including dendrites and axons. Taken together, our data support a model in which the spastin interaction with CRMP5 promotes neurite outgrowth by controlling the microtubule dynamics.
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Affiliation(s)
- Zhisheng Ji
- Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou, China.,Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Guowei Zhang
- Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou, China.,Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Li Chen
- Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Jiong Li
- Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Yuhao Yang
- Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou, China.,Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Caihui Cha
- Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, China
| | - Jifeng Zhang
- Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Hongsheng Lin
- Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou, China.,Department of Anatomy, Medical College of Jinan University, Guangzhou, China
| | - Guoqing Guo
- Department of Anatomy, Medical College of Jinan University, Guangzhou, China
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10
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Gan Q, Watanabe S. Synaptic Vesicle Endocytosis in Different Model Systems. Front Cell Neurosci 2018; 12:171. [PMID: 30002619 PMCID: PMC6031744 DOI: 10.3389/fncel.2018.00171] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 06/01/2018] [Indexed: 11/13/2022] Open
Abstract
Neurotransmission in complex animals depends on a choir of functionally distinct synapses releasing neurotransmitters in a highly coordinated manner. During synaptic signaling, vesicles fuse with the plasma membrane to release their contents. The rate of vesicle fusion is high and can exceed the rate at which synaptic vesicles can be re-supplied by distant sources. Thus, local compensatory endocytosis is needed to replenish the synaptic vesicle pools. Over the last four decades, various experimental methods and model systems have been used to study the cellular and molecular mechanisms underlying synaptic vesicle cycle. Clathrin-mediated endocytosis is thought to be the predominant mechanism for synaptic vesicle recycling. However, recent studies suggest significant contribution from other modes of endocytosis, including fast compensatory endocytosis, activity-dependent bulk endocytosis, ultrafast endocytosis, as well as kiss-and-run. Currently, it is not clear whether a universal model of vesicle recycling exist for all types of synapses. It is possible that each synapse type employs a particular mode of endocytosis. Alternatively, multiple modes of endocytosis operate at the same synapse, and the synapse toggles between different modes depending on its activity level. Here we compile review and research articles based on well-characterized model systems: frog neuromuscular junctions, C. elegans neuromuscular junctions, Drosophila neuromuscular junctions, lamprey reticulospinal giant axons, goldfish retinal ribbon synapses, the calyx of Held, and rodent hippocampal synapses. We will compare these systems in terms of their known modes and kinetics of synaptic vesicle endocytosis, as well as the underlying molecular machineries. We will also provide the future development of this field.
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Affiliation(s)
- Quan Gan
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Shigeki Watanabe
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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11
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Zhang J, Zhao B, Zhu X, Li J, Wu F, Li S, Gong X, Cha C, Guo G. Phosphorylation and SUMOylation of CRMP2 regulate the formation and maturation of dendritic spines. Brain Res Bull 2018; 139:21-30. [PMID: 29425794 DOI: 10.1016/j.brainresbull.2018.02.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/24/2018] [Accepted: 02/02/2018] [Indexed: 10/18/2022]
Abstract
The posttranslational modifications of CRMP2 play an important role in axon outgrowth, cell polarization and dendritic morphogenesis. However, whether CRMP2 and its posttranslational modifications are involved in dendritic spine development specifically is not completely clear. Here, we show that CRMP2 can promote the formation and maturation of dendritic spines in cultured hippocampal neurons. Overexpression of CRMP2 results in an increase in the density of spines especially the mushroom-shape spines. The amplitude and frequency of miniature excitatory postsynaptic currents (mEPSCs) are both enhanced and the intensity of PSD95 is strengthened in the neurons with CRMP2 overexpression. Furthermore, dephosphorylation of CRMP2 at Thr514 and deSUMOylation at Lys374 can further promote the formation and maturation of dendritic spines, whereas, no cross-talk is found between these two posttranslational modifications in the regulation of dendritic spine formation and maturation. Taken together, our data support a model in which phosphorylation and SUMOylation modification of CRMP2 independently promote the formation and maturation of dendritic spines and participate in the process of dendritic spine plasticity.
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Affiliation(s)
- Jifeng Zhang
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China.
| | - Bo Zhao
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China; Department of Rehabilitation Medicine, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Xiaonan Zhu
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Jiong Li
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Fengming Wu
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Sumei Li
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Xiaobing Gong
- Department of Gastroenterology, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Caihui Cha
- Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, 510120, China.
| | - Guoqing Guo
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China.
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12
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Endophilin2 Interacts with GluA1 to Mediate AMPA Receptor Endocytosis Induced by Oligomeric Amyloid- β. Neural Plast 2017; 2017:8197085. [PMID: 28758034 PMCID: PMC5516760 DOI: 10.1155/2017/8197085] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 05/08/2017] [Accepted: 06/08/2017] [Indexed: 01/08/2023] Open
Abstract
Amyloid-β (Aβ) plays an important role in Alzheimer's disease (AD), as oligomeric Aβ induces loss of postsynaptic AMPA receptors (AMPARs) leading to cognitive deficits. The loss of postsynaptic AMPARs is mediated through the clathrin-dependent endocytosis pathway, in which endophilin2 is one of the important regulatory proteins. Endophilin2, which is enriched in both the pre- and postsynaptic membrane, has previously been reported to be important for recycling of synaptic vesicles at the presynaptic membrane. However, the role of endophilin2 in oligomeric Aβ-induced postsynaptic AMPAR endocytosis is not well understood. In this study, we show that endophilin2 does not affect constitutive AMPAR endocytosis. Endophilin2 knockdown, but not overexpression, resisted oligomeric Aβ-induced AMPAR dysfunction. Moreover, endophilin2 colocalized and interacted with GluA1, a subunit of AMPAR, to regulate oligomeric Aβ-induced AMPAR endocytosis. Thus, we have determined a role of endophilin2 in oligomeric Aβ-induced postsynaptic AMPAR dysfunction, indicating possible directions for preventing the loss of AMPARs in cognitive impairment and providing evidence for the clinical treatment of AD.
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13
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Cha C, Zhang J, Ji Z, Tan M, Li S, Wu F, Chen K, Gong S, Guo G, Lin H. CRMP4 regulates dendritic growth and maturation via the interaction with actin cytoskeleton in cultured hippocampal neurons. Brain Res Bull 2016; 124:286-94. [PMID: 27339813 DOI: 10.1016/j.brainresbull.2016.06.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 06/02/2016] [Accepted: 06/16/2016] [Indexed: 02/07/2023]
Abstract
CRMP family proteins (CRMPs) are critical for neurite outgrowth and maturation in the developing nervous system. However, the distinct roles of CRMP isoforms remain to be elucidated, especially in dendritic development. Here, we show that CRMP4 is sufficient and necessary for dendritic growth and maturation in cultured hippocampal neurons. Overexpression of CRMP4 promotes and genetic knockdown of CRMP4 inhibits the amount of dendritic tips, total dendritic length, spine density, and the frequency but not amplitude of miniature excitatory synaptic current. By GST-pulldown assay, we reveal that CRMP4 interacts with actin cytoskeleton by its C-terminal region, but not by N-terminal. Overexpression of actin-interacting region of CRMP4 promoted dendritic growth and maturation as CRMP4 wildtype. Taken together, these results suggest that CRMP4 is involved in dendritic development via the interaction with actin cytoskeleton in hippocampal neurons.
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Affiliation(s)
- Caihui Cha
- Department of Pediatrics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China; Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, 510120, China; Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Jifeng Zhang
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Zhisheng Ji
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China; Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Minghui Tan
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China; Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Sumei Li
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Fengming Wu
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China
| | - Keen Chen
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China; Department of Neurosurgery, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Sitang Gong
- Department of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou, 510120, China
| | - Guoqing Guo
- Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China.
| | - Hongsheng Lin
- Department of Orthopedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
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14
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SH3GL1 inhibition reverses multidrug resistance in colorectal cancer cells by downregulation of MDR1/P-glycoprotein via EGFR/ERK/AP-1 pathway. Tumour Biol 2016; 37:12153-12160. [DOI: 10.1007/s13277-016-5092-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/15/2016] [Indexed: 01/14/2023] Open
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15
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Gong X, Tan M, Gao Y, Chen K, Guo G. CRMP‑5 interacts with actin to regulate neurite outgrowth. Mol Med Rep 2015; 13:1179-85. [PMID: 26677106 PMCID: PMC4732841 DOI: 10.3892/mmr.2015.4662] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 10/29/2015] [Indexed: 11/17/2022] Open
Abstract
CRMP family proteins (CRMPs) are abundantly expressed in the developing nervous system mediating growth cone guidance, neuronal polarity and axon elongation. CRMP-5 has been indicated to serve a critical role in neurite outgrowth. However, the detailed mechanisms of how CRMP-5 regulates neurite outgrowth remain unclear. In the current study, co-immunoprecipitation was used to identify the fact that CRMP-5 interacted with the actin and tubulin cytoskeleton networks in the growth cones of developing hippocampal neurons. CRMP-5 exhibited increased affinity towards actin when compared with microtubules. Immunocytochemistry was used to identify the fact that CRMP-5 colocalized with actin predominantly in the C-domain and T-zone in growth cones. In addition, genetic inhibition of CRMP-5 by siRNA suppressed the expression of actin, growth cone development and neurite outgrowth. Overexpression of CRMP-5 promoted the interaction with actin, growth cone development and hippocampal neurite outgrowth. Taken together, these data suggest that CRMP-5 is able to interact with the actin cytoskeleton network in the growth cone and affect growth cone development and neurite outgrowth via this interaction in developing hippocampal neurons.
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Affiliation(s)
- Xiaobing Gong
- Department of Gastroenterology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Minghui Tan
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Yuan Gao
- Department of Gastroenterology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Keen Chen
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Guoqing Guo
- Department of Anatomy, Medical College of Jinan University, Guangzhou, Guangdong 510630, P.R. China
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16
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Distinct Functions of Endophilin Isoforms in Synaptic Vesicle Endocytosis. Neural Plast 2015; 2015:371496. [PMID: 26682072 PMCID: PMC4670672 DOI: 10.1155/2015/371496] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/15/2015] [Accepted: 06/23/2015] [Indexed: 11/23/2022] Open
Abstract
Endophilin isoforms perform distinct characteristics in their interactions with N-type Ca2+ channels and dynamin. However, precise functional differences for the endophilin isoforms on synaptic vesicle (SV) endocytosis remain unknown. By coupling RNA interference and electrophysiological recording techniques in cultured rat hippocampal neurons, we investigated the functional differences of three isoforms of endophilin in SV endocytosis. The results showed that the amplitude of normalized evoked excitatory postsynaptic currents in endophilin1 knockdown neurons decreased significantly for both single train and multiple train stimulations. Similar results were found using endophilin2 knockdown neurons, whereas endophilin3 siRNA exhibited no change compared with control neurons. Endophilin1 and endophilin2 affected SV endocytosis, but the effect of endophilin1 and endophilin2 double knockdown was not different from that of either knockdown alone. This result suggested that endophilin1 and endophilin2 functioned together but not independently during SV endocytosis. Taken together, our results indicate that SV endocytosis is sustained by endophilin1 and endophilin2 isoforms, but not by endophilin3, in primary cultured hippocampal neurons.
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17
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Li J, Chen Y, Li M, Carpenter MA, McDougle RM, Luengas EM, Macdonald PJ, Harris RS, Mueller JD. APOBEC3 multimerization correlates with HIV-1 packaging and restriction activity in living cells. J Mol Biol 2014; 426:1296-307. [PMID: 24361275 PMCID: PMC3977201 DOI: 10.1016/j.jmb.2013.12.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 12/10/2013] [Accepted: 12/10/2013] [Indexed: 12/30/2022]
Abstract
APOBEC3G belongs to a family of DNA cytosine deaminases that are involved in the restriction of a broad number of retroviruses including human immunodeficiency virus type 1 (HIV-1). Prior studies have identified two distinct mechanistic steps in Vif-deficient HIV-1 restriction: packaging into virions and deaminating viral cDNA. APOBEC3A, for example, although highly active, is not packaged and is therefore not restrictive. APOBEC3G, on the other hand, although having weaker enzymatic activity, is packaged into virions and is strongly restrictive. Although a number of studies have described the propensity for APOBEC3 oligomerization, its relevance to HIV-1 restriction remains unclear. Here, we address this problem by examining APOBEC3 oligomerization in living cells using molecular brightness analysis. We find that APOBEC3G forms high-order multimers as a function of protein concentration. In contrast, APOBEC3A, APOBEC3C and APOBEC2 are monomers at all tested concentrations. Among other members of the APOBEC3 family, we show that the multimerization propensities of APOBEC3B, APOBEC3D, APOBEC3F and APOBEC3H (haplotype II) bear more resemblance to APOBEC3G than to APOBEC3A/3C/2. Prior studies have shown that all of these multimerizing APOBEC3 proteins, but not the monomeric family members, have the capacity to package into HIV-1 particles and restrict viral infectivity. This correlation between oligomerization and restriction is further evidenced by two different APOBEC3G mutants, which are each compromised for multimerization, packaging and HIV-1 restriction. Overall, our results imply that multimerization of APOBEC3 proteins may be related to the packaging mechanism and ultimately to virus restriction.
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Affiliation(s)
- Jinhui Li
- School of Physics and Astronomy, University of Minnesota, 116 Church Street Southeast, Minneapolis, MN 55455, USA; Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA
| | - Yan Chen
- School of Physics and Astronomy, University of Minnesota, 116 Church Street Southeast, Minneapolis, MN 55455, USA; Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA
| | - Ming Li
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, 321 Church Street Southeast, Minneapolis, MN 55455, USA
| | - Michael A Carpenter
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, 321 Church Street Southeast, Minneapolis, MN 55455, USA
| | - Rebecca M McDougle
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, 321 Church Street Southeast, Minneapolis, MN 55455, USA
| | - Elizabeth M Luengas
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, 321 Church Street Southeast, Minneapolis, MN 55455, USA
| | - Patrick J Macdonald
- Department of Biomedical Engineering, University of Minnesota, 312 Church Street Southeast, Minneapolis, MN 55455, USA
| | - Reuben S Harris
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA; Department of Biochemistry, Molecular Biology and Biophysics, 321 Church Street Southeast, Minneapolis, MN 55455, USA
| | - Joachim D Mueller
- School of Physics and Astronomy, University of Minnesota, 116 Church Street Southeast, Minneapolis, MN 55455, USA; Institute for Molecular Virology, University of Minnesota, 515 Delaware Street Southeast, Minneapolis, MN 55455, USA; Department of Biomedical Engineering, University of Minnesota, 312 Church Street Southeast, Minneapolis, MN 55455, USA.
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