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George K, Hoang HTM, Tibbs T, Nagaraja RY, Li G, Troyano-Rodriguez E, Ahmad M. Robust GRK2/3/6-dependent desensitization of oxytocin receptor in neurons. iScience 2024; 27:110047. [PMID: 38883814 PMCID: PMC11179071 DOI: 10.1016/j.isci.2024.110047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 02/22/2024] [Accepted: 05/17/2024] [Indexed: 06/18/2024] Open
Abstract
Oxytocin plays critical roles in the brain as a neuromodulator, regulating social and other affective behavior. However, the regulatory mechanisms controlling oxytocin receptor (OXTR) signaling in neurons remain unexplored. In this study, we have identified robust and rapid-onset desensitization of OXTR response in multiple regions of the mouse brain. Both cell autonomous spiking response and presynaptic activation undergo similar agonist-induced desensitization. G-protein-coupled receptor kinases (GRK) GRK2, GRK3, and GRK6 are recruited to the activated OXTR in neurons, followed by recruitment of β-arrestin-1 and -2. Neuronal OXTR desensitization was impaired by suppression of GRK2/3/6 kinase activity but remained unaltered with double knockout of β-arrestin-1 and -2. Additionally, we observed robust agonist-induced internalization of neuronal OXTR and its Rab5-dependent recruitment to early endosomes, which was impaired by GRK2/3/6 inhibition. This work defines distinctive aspects of the mechanisms governing OXTR desensitization and internalization in neurons compared to prior studies in heterologous cells.
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Affiliation(s)
- Kiran George
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Hanh T M Hoang
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Taryn Tibbs
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Raghavendra Y Nagaraja
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Guangpu Li
- Department of Biochemistry and Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Eva Troyano-Rodriguez
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Mohiuddin Ahmad
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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2
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Cao YY, Wu LL, Li XN, Yuan YL, Zhao WW, Qi JX, Zhao XY, Ward N, Wang J. Molecular Mechanisms of AMPA Receptor Trafficking in the Nervous System. Int J Mol Sci 2023; 25:111. [PMID: 38203282 PMCID: PMC10779435 DOI: 10.3390/ijms25010111] [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: 11/24/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Synaptic plasticity enhances or reduces connections between neurons, affecting learning and memory. Postsynaptic AMPARs mediate greater than 90% of the rapid excitatory synaptic transmission in glutamatergic neurons. The number and subunit composition of AMPARs are fundamental to synaptic plasticity and the formation of entire neural networks. Accordingly, the insertion and functionalization of AMPARs at the postsynaptic membrane have become a core issue related to neural circuit formation and information processing in the central nervous system. In this review, we summarize current knowledge regarding the related mechanisms of AMPAR expression and trafficking. The proteins related to AMPAR trafficking are discussed in detail, including vesicle-related proteins, cytoskeletal proteins, synaptic proteins, and protein kinases. Furthermore, significant emphasis was placed on the pivotal role of the actin cytoskeleton, which spans throughout the entire transport process in AMPAR transport, indicating that the actin cytoskeleton may serve as a fundamental basis for AMPAR trafficking. Additionally, we summarize the proteases involved in AMPAR post-translational modifications. Moreover, we provide an overview of AMPAR transport and localization to the postsynaptic membrane. Understanding the assembly, trafficking, and dynamic synaptic expression mechanisms of AMPAR may provide valuable insights into the cognitive decline associated with neurodegenerative diseases.
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Affiliation(s)
- Yi-Yang Cao
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Ling-Ling Wu
- School of Medicine, Shanghai University, Shanghai 200444, China;
| | - Xiao-Nan Li
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Yu-Lian Yuan
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Wan-Wei Zhao
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Jing-Xuan Qi
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Xu-Yu Zhao
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
| | - Natalie Ward
- Medical Laboratory, Exceptional Community Hospital, 19060 N John Wayne Pkwy, Maricopa, AZ 85139, USA;
| | - Jiao Wang
- Laboratory of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai 200444, China; (Y.-Y.C.); (X.-N.L.); (Y.-L.Y.); (W.-W.Z.); (J.-X.Q.); (X.-Y.Z.)
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3
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Sultana P, Novotny J. Rab11 and Its Role in Neurodegenerative Diseases. ASN Neuro 2022; 14:17590914221142360. [PMID: 36464817 PMCID: PMC9726856 DOI: 10.1177/17590914221142360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022] Open
Abstract
Vesicles mediate the trafficking of membranes/proteins in the endocytic and secretory pathways. These pathways are regulated by small GTPases of the Rab family. Rab proteins belong to the Ras superfamily of GTPases, which are significantly involved in various intracellular trafficking and signaling processes in the nervous system. Rab11 is known to play a key role especially in recycling many proteins, including receptors important for signal transduction and preservation of functional activities of nerve cells. Rab11 activity is controlled by GEFs (guanine exchange factors) and GAPs (GTPase activating proteins), which regulate its function through modulating GTP/GDP exchange and the intrinsic GTPase activity, respectively. Rab11 is involved in the transport of several growth factor molecules important for the development and repair of neurons. Overexpression of Rab11 has been shown to significantly enhance vesicle trafficking. On the other hand, a reduced expression of Rab11 was observed in several neurodegenerative diseases. Current evidence appears to support the notion that Rab11 and its cognate proteins may be potential targets for therapeutic intervention. In this review, we briefly discuss the function of Rab11 and its related interaction partners in intracellular pathways that may be involved in neurodegenerative processes.
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Affiliation(s)
| | - Jiri Novotny
- Jiri Novotny, Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic.
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4
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The Rab11-regulated endocytic pathway and BDNF/TrkB signaling: Roles in plasticity changes and neurodegenerative diseases. Neurobiol Dis 2022; 171:105796. [PMID: 35728773 DOI: 10.1016/j.nbd.2022.105796] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 05/10/2022] [Accepted: 06/14/2022] [Indexed: 02/08/2023] Open
Abstract
Neurons are highly polarized cells that rely on the intracellular transport of organelles. This process is regulated by molecular motors such as dynein and kinesins and the Rab family of monomeric GTPases that together help move cargo along microtubules in dendrites, somas, and axons. Rab5-Rab11 GTPases regulate receptor trafficking along early-recycling endosomes, which is a process that determines the intracellular signaling output of different signaling pathways, including those triggered by BDNF binding to its tyrosine kinase receptor TrkB. BDNF is a well-recognized neurotrophic factor that regulates experience-dependent plasticity in different circuits in the brain. The internalization of the BDNF/TrkB complex results in signaling endosomes that allow local signaling in dendrites and presynaptic terminals, nuclear signaling in somas and dynein-mediated long-distance signaling from axons to cell bodies. In this review, we briefly discuss the organization of the endocytic pathway and how Rab11-recycling endosomes interact with other endomembrane systems. We further expand upon the roles of the Rab11-recycling pathway in neuronal plasticity. Then, we discuss the BDNF/TrkB signaling pathways and their functional relationships with the postendocytic trafficking of BDNF, including axonal transport, emphasizing the role of BDNF signaling endosomes, particularly Rab5-Rab11 endosomes, in neuronal plasticity. Finally, we discuss the evidence indicating that the dysfunction of the early-recycling pathway impairs BDNF signaling, contributing to several neurodegenerative diseases.
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5
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Koss DJ, Campesan S, Giorgini F, Outeiro TF. Dysfunction of RAB39B-Mediated Vesicular Trafficking in Lewy Body Diseases. Mov Disord 2021; 36:1744-1758. [PMID: 33939203 DOI: 10.1002/mds.28605] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 03/09/2021] [Accepted: 03/12/2021] [Indexed: 12/16/2022] Open
Abstract
Intracellular vesicular trafficking is essential for neuronal development, function, and homeostasis and serves to process, direct, and sort proteins, lipids, and other cargo throughout the cell. This intricate system of membrane trafficking between different compartments is tightly orchestrated by Ras analog in brain (RAB) GTPases and their effectors. Of the 66 members of the RAB family in humans, many have been implicated in neurodegenerative diseases and impairment of their functions contributes to cellular stress, protein aggregation, and death. Critically, RAB39B loss-of-function mutations are known to be associated with X-linked intellectual disability and with rare early-onset Parkinson's disease. Moreover, recent studies have highlighted altered RAB39B expression in idiopathic cases of several Lewy body diseases (LBDs). This review contextualizes the role of RAB proteins in LBDs and highlights the consequences of RAB39B impairment in terms of endosomal trafficking, neurite outgrowth, synaptic maturation, autophagy, as well as alpha-synuclein homeostasis. Additionally, the potential for therapeutic intervention is examined via a discussion of the recent progress towards the development of specific RAB modulators. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- David J Koss
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Susanna Campesan
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, UK
| | - Flaviano Giorgini
- Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester, UK
| | - Tiago F Outeiro
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Goettingen, Goettingen, Germany.,Max Planck Institute for Experimental Medicine, Goettingen, Germany.,Scientific employee with a honorary contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Göttingen, Germany
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6
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Yoon J, Garo J, Lee M, Sun J, Hwang YS, Daar IO. Rab11fip5 regulates telencephalon development via ephrinB1 recycling. Development 2021; 148:dev.196527. [PMID: 33462110 PMCID: PMC7875491 DOI: 10.1242/dev.196527] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 12/25/2020] [Indexed: 12/12/2022]
Abstract
Rab11 family-interacting protein 5 (Rab11fip5) is an adaptor protein that binds to the small GTPase Rab11, which has an important function in endosome recycling and trafficking of cellular proteins to the plasma membrane. Rab11fip5 is involved in many cellular processes, such as cytoskeleton rearrangement, iron uptake and exocytosis in neuroendocrine cells, and is also known as a candidate gene for autism-spectrum disorder. However, the role of Rab11fip5 during early embryonic development is not clearly understood. In this study, we identified Rab11fip5 as a protein that interacts with ephrinB1, a transmembrane ligand for Eph receptors. The PDZ binding motif in ephrinB1 and the Rab-binding domain in Rab11fip5 are necessary for their interaction in a complex. EphrinB1 and Rab11fip5 display overlapping expression in the telencephalon of developing amphibian embryos. The loss of Rab11fip5 function causes a reduction in telencephalon size and a decrease in the expression level of ephrinB1. Moreover, morpholino oligonucleotide-mediated knockdown of Rab11fip5 decreases cell proliferation in the telencephalon. The overexpression of ephrinB1 rescues these defects, suggesting that ephrinB1 recycling by the Rab11/Rab11fip5 complex is crucial for proper telencephalon development. Summary: Rab11fip5, genetic mutations of which are associated with autism spectrum disorders in humans, plays a role in regulating telencephalon development via recycling of the crucial cargo ephrinB1.
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Affiliation(s)
- Jaeho Yoon
- Cancer and Developmental Biology Laboratory (CDBL), Center for Cancer Research (CCR) - Frederick, National Cancer Institute, Frederick, MD 21702, USA
| | - Jerlin Garo
- Cancer and Developmental Biology Laboratory (CDBL), Center for Cancer Research (CCR) - Frederick, National Cancer Institute, Frederick, MD 21702, USA
| | - Moonsup Lee
- Cancer and Developmental Biology Laboratory (CDBL), Center for Cancer Research (CCR) - Frederick, National Cancer Institute, Frederick, MD 21702, USA
| | - Jian Sun
- Cancer and Developmental Biology Laboratory (CDBL), Center for Cancer Research (CCR) - Frederick, National Cancer Institute, Frederick, MD 21702, USA
| | - Yoo-Seok Hwang
- Cancer and Developmental Biology Laboratory (CDBL), Center for Cancer Research (CCR) - Frederick, National Cancer Institute, Frederick, MD 21702, USA
| | - Ira O Daar
- Cancer and Developmental Biology Laboratory (CDBL), Center for Cancer Research (CCR) - Frederick, National Cancer Institute, Frederick, MD 21702, USA
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7
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Li D, Bradley T, Cain DW, Pedroza-Pacheco I, Aggelakopoulou M, Parks R, Barr M, Xia SM, Scearce R, Bowman C, Stevens G, Newman A, Hora B, Chen Y, Riebe K, Wang Y, Sempowski G, Saunders KO, Borrow P, Haynes BF. RAB11FIP5-Deficient Mice Exhibit Cytokine-Related Transcriptomic Signatures. Immunohorizons 2020; 4:713-728. [PMID: 33172842 PMCID: PMC8050958 DOI: 10.4049/immunohorizons.2000088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 10/23/2020] [Indexed: 11/19/2022] Open
Abstract
Rab11 recycling endosomes are involved in immunological synaptic functions, but the roles of Rab11 family–interacting protein 5 (Rab11Fip5), one of the Rab11 effectors, in the immune system remain obscure. Our previous study demonstrated that RAB11FIP5 transcripts are significantly elevated in PBMCs from HIV-1–infected individuals, making broadly HIV-1–neutralizing Abs compared with those without broadly neutralizing Abs; however, the role of Rab11FiP5 in immune functions remains unclear. In this study, a RAB11FIP5 gene knockout (RAB11FIP5−/−) mouse model was employed to study the role of Rab11Fip5 in immune responses. RAB11FIP5−/− mice exhibited no perturbation in lymphoid tissue cell subsets, and Rab11Fip5 was not required for serum Ab induction following HIV-1 envelope immunization, Ab transcytosis to mucosal sites, or survival after influenza challenge. However, differences were observed in multiple transcripts, including cytokine genes, in lymphocyte subsets from envelope-immunized RAB11FIP5−/− versus control mice. These included alterations in several genes in NK cells that mirrored observations in NKs from HIV-infected humans expressing less RAB11FIP5, although Rab11Fip5 was dispensable for NK cell cytolytic activity. Notably, immunized RAB11FIP5−/− mice had lower IL4 expression in CD4+ T follicular helper cells and showed lower TNF expression in CD8+ T cells. Likewise, TNF-α production by human CD8+ T cells correlated with PBMC RAB11FIP5 expression. These observations in RAB11FIP5−/− mice suggest a role for Rab11Fip5 in regulating cytokine responses.
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Affiliation(s)
- Dapeng Li
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710;
| | - Todd Bradley
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710.,Department of Medicine, Duke University School of Medicine, Durham, NC 27710
| | - Derek W Cain
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710.,Department of Medicine, Duke University School of Medicine, Durham, NC 27710
| | - Isabela Pedroza-Pacheco
- Nuffield Department of Clinical Medicine, University of Oxford, OX3 7FZ Oxford, United Kingdom
| | - Maria Aggelakopoulou
- Nuffield Department of Clinical Medicine, University of Oxford, OX3 7FZ Oxford, United Kingdom
| | - Robert Parks
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Maggie Barr
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Shi-Mao Xia
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Richard Scearce
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Cindy Bowman
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Grace Stevens
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Amanda Newman
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Bhavna Hora
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Yue Chen
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Kristina Riebe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Yunfei Wang
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Gregory Sempowski
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Kevin O Saunders
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710.,Department of Immunology, Duke University School of Medicine, Durham, NC 27710; and.,Department of Surgery, Duke University, Durham, NC 27710
| | - Persephone Borrow
- Nuffield Department of Clinical Medicine, University of Oxford, OX3 7FZ Oxford, United Kingdom
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710; .,Department of Medicine, Duke University School of Medicine, Durham, NC 27710.,Department of Immunology, Duke University School of Medicine, Durham, NC 27710; and
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Proteasomal-Mediated Degradation of AKAP150 Accompanies AMPAR Endocytosis during cLTD. eNeuro 2020; 7:ENEURO.0218-19.2020. [PMID: 32205379 PMCID: PMC7163082 DOI: 10.1523/eneuro.0218-19.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 02/17/2020] [Accepted: 03/02/2020] [Indexed: 12/26/2022] Open
Abstract
The number and function of synaptic AMPA receptors (AMPARs) tightly regulates excitatory synaptic transmission. Current evidence suggests that AMPARs are inserted into the postsynaptic membrane during long-term potentiation (LTP) and are removed from the membrane during long-term depression (LTD). Dephosphorylation of GluA1 at Ser-845 and enhanced endocytosis are critical events in the modulation of LTD. Moreover, changes in scaffold proteins from the postsynaptic density (PSD) could be also related to AMPAR regulation in LTD. In the present study we analyzed the effect of chemical LTD (cLTD) on A-kinase anchoring protein (AKAP)150 and AMPARs levels in mouse-cultured neurons. We show that cLTD induces AKAP150 protein degradation via proteasome, coinciding with GluA1 dephosphorylation at Ser-845 and endocytosis of GluA1-containing AMPARs. Pharmacological inhibition of proteasome activity, but not phosphatase calcineurin (CaN), reverted cLTD-induced AKAP150 protein degradation. Importantly, AKAP150 silencing induced dephosphorylation of GluA1 Ser-845 and GluA1-AMPARs endocytosis while AKAP150 overexpression blocked cLTD-mediated GluA1-AMPARs endocytosis. Our results provide direct evidence that cLTD-induced AKAP150 degradation by the proteasome contributes to synaptic AMPARs endocytosis.
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9
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Biever A, Glock C, Tushev G, Ciirdaeva E, Dalmay T, Langer JD, Schuman EM. Monosomes actively translate synaptic mRNAs in neuronal processes. Science 2020; 367:367/6477/eaay4991. [PMID: 32001627 DOI: 10.1126/science.aay4991] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/29/2019] [Accepted: 12/18/2019] [Indexed: 12/13/2022]
Abstract
To accommodate their complex morphology, neurons localize messenger RNAs (mRNAs) and ribosomes near synapses to produce proteins locally. However, a relative paucity of polysomes (considered the active sites of translation) detected in electron micrographs of neuronal processes has suggested a limited capacity for local protein synthesis. In this study, we used polysome profiling together with ribosome footprinting of microdissected rodent synaptic regions to reveal a surprisingly high number of dendritic and/or axonal transcripts preferentially associated with monosomes (single ribosomes). Furthermore, the neuronal monosomes were in the process of active protein synthesis. Most mRNAs showed a similar translational status in the cell bodies and neurites, but some transcripts exhibited differential ribosome occupancy in the compartments. Monosome-preferring transcripts often encoded high-abundance synaptic proteins. Thus, monosome translation contributes to the local neuronal proteome.
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Affiliation(s)
- Anne Biever
- Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Caspar Glock
- Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Georgi Tushev
- Max Planck Institute for Brain Research, Frankfurt, Germany
| | | | - Tamas Dalmay
- Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Julian D Langer
- Max Planck Institute for Brain Research, Frankfurt, Germany.,Max Planck Institute of Biophysics, Frankfurt, Germany
| | - Erin M Schuman
- Max Planck Institute for Brain Research, Frankfurt, Germany.
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10
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Royo M, Gutiérrez Y, Fernández-Monreal M, Gutiérrez-Eisman S, Jiménez R, Jurado S, Esteban JA. A retention-release mechanism based on RAB11FIP2 for AMPA receptor synaptic delivery during long-term potentiation. J Cell Sci 2019; 132:jcs.234237. [PMID: 31757887 DOI: 10.1242/jcs.234237] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 11/15/2019] [Indexed: 02/05/2023] Open
Abstract
It is well--established that Rab11-dependent recycling endosomes drive the activity-dependent delivery of AMPA receptors (AMPARs) into synapses during long-term potentiation (LTP). Nevertheless, the molecular basis for this specialized function of recycling endosomes is still unknown. Here, we have investigated RAB11FIP2 (FIP2 hereafter) as a potential effector of Rab11-dependent trafficking during LTP in rat hippocampal slices. Surprisingly, we found that FIP2 operates independently from Rab11 proteins, and acts as a negative regulator of AMPAR synaptic trafficking. Under basal conditions, FIP2 associates with AMPARs at immobile compartments, separately from recycling endosomes. Using shRNA-mediated knockdown, we found that FIP2 prevents GluA1 (encoded by the Gria1 gene) AMPARs from reaching the surface of dendritic spines in the absence of neuronal stimulation. Upon induction of LTP, FIP2 is rapidly mobilized, dissociates from AMPARs and undergoes dephosphorylation. Interestingly, this dissociation of the FIP2-AMPAR complex, together with FIP2 dephosphorylation, is required for LTP, but the interaction between FIP2 and Rab11 proteins is not. Based on these results, we propose a retention-release mechanism, where FIP2 acts as a gate that restricts the trafficking of AMPARs, until LTP induction triggers their release and allows synaptic delivery.
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Affiliation(s)
- María Royo
- Department of Neurobiology, Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), 28049 Madrid, Spain
| | - Yolanda Gutiérrez
- Department of Neurobiology, Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), 28049 Madrid, Spain
| | - Mónica Fernández-Monreal
- Department of Neurobiology, Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), 28049 Madrid, Spain
| | - Silvia Gutiérrez-Eisman
- Department of Neurobiology, Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), 28049 Madrid, Spain
| | - Raquel Jiménez
- Department of Neurobiology, Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), 28049 Madrid, Spain
| | - Sandra Jurado
- Instituto de Neurociencias CSIC-UMH, 03550 San Juan de Alicante, Spain
| | - José A Esteban
- Department of Neurobiology, Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), 28049 Madrid, Spain
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Troyano-Rodriguez E, Mann S, Ullah R, Ahmad M. PRRT1 regulates basal and plasticity-induced AMPA receptor trafficking. Mol Cell Neurosci 2019; 98:155-163. [PMID: 31216424 DOI: 10.1016/j.mcn.2019.06.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 06/07/2019] [Accepted: 06/13/2019] [Indexed: 01/20/2023] Open
Abstract
AMPA-type glutamate receptors (AMPAR) are one of the principal mediators of fast excitatory synaptic transmission in the brain. These receptors associate with multiple integral membrane proteins which influence their trafficking and channel properties. Proline-rich transmembrane protein 1 (PRRT1) is a membrane protein and an understudied component of native AMPAR complexes. In order to understand the regulation of AMPARs by PRRT1, we have performed electrophysiological and biochemical investigations on acute hippocampal slices derived from PRRT1 knockout mice. Our results show that PRRT1 controls the levels of AMPARs at the cell surface, though it is dispensable for synaptic transmission. PRRT1 has differential effects on the stability of AMPAR GluA1 subunit phosphorylated at S845 and at S831, two residues at which the phosphorylation status has major influences on receptor trafficking. Furthermore, PRRT1 is required for NMDA receptor-dependent long-term depression (LTD) and proper NMDA-induced AMPAR trafficking. These findings position PRRT1 as an important regulator of AMPAR stabilization and trafficking in different subcellular pools under basal conditions and during synaptic plasticity.
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Affiliation(s)
- Eva Troyano-Rodriguez
- Department of Cell Biology and Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Shivani Mann
- Department of Cell Biology and Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Raja Ullah
- Department of Cell Biology and Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Mohiuddin Ahmad
- Department of Cell Biology and Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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12
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Kim T, Tanaka-Yamamoto K. Postsynaptic Stability and Variability Described by a Stochastic Model of Endosomal Trafficking. Front Cell Neurosci 2019; 13:72. [PMID: 30863286 PMCID: PMC6399135 DOI: 10.3389/fncel.2019.00072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 02/13/2019] [Indexed: 12/04/2022] Open
Abstract
Neurons undergo dynamic processes of constitutive AMPA-type glutamate receptor (AMPAR) trafficking, such as the insertion and internalization of AMPARs by exocytosis and endocytosis, while stably maintaining synaptic efficacy. Studies using advanced imaging techniques have suggested that the frequency of these constitutive trafficking processes, as well as the number of AMPARs that are involved in a particular event highly fluctuate. In addition, mechanisms that trigger some forms of synaptic plasticity have been shown to include not only these processes but also additional fluctuating processes, such as the sorting of AMPARs to late endosomes (LEs). Thus, the regulation of postsynaptic AMPARs by the endosomal trafficking system appears to have superficially conflicting properties between the stability or organized control of plasticity and highly fluctuating or stochastic processes. However, it is not clear how the endosomal trafficking system reconciles and utilizes such conflicting properties. Although deterministic models have been effective to describe the stable maintenance of synaptic AMPAR numbers by constitutive recycling, as well as the involvement of endosomal trafficking in synaptic plasticity, they do not take stochasticity into account. In this study, we introduced the stochasticity into the model of each crucial machinery of the endosomal trafficking system. The specific questions we solved by our improved model are whether stability is accomplished even with a combination of fluctuating processes, and how overall variability occurs while controlling long-term synaptic depression (LTD). Our new stochastic model indeed demonstrated the stable regulation of postsynaptic AMPAR numbers at the basal state and during LTD maintenance, despite fast fluctuations in AMPAR numbers as well as high variability in the time course and amounts of LTD. In addition, our analysis suggested that the high variability arising from this stochasticity is beneficial for reproducing the relatively constant timing of LE sorting for LTD. We therefore propose that the coexistence of stability and stochasticity in the endosomal trafficking system is suitable for stable synaptic transmission and the reliable induction of synaptic plasticity, with variable properties that have been observed experimentally.
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Affiliation(s)
- Taegon Kim
- Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, South Korea
| | - Keiko Tanaka-Yamamoto
- Center for Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, South Korea.,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul, South Korea
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Liguori M, Nuzziello N, Simone M, Amoroso N, Viterbo RG, Tangaro S, Consiglio A, Giordano P, Bellotti R, Trojano M. Association between miRNAs expression and cognitive performances of Pediatric Multiple Sclerosis patients: A pilot study. Brain Behav 2019; 9:e01199. [PMID: 30656857 PMCID: PMC6379516 DOI: 10.1002/brb3.1199] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 11/28/2018] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION The Pediatric onset of Multiple Sclerosis (PedMS) occurs in up to 10% of all cases. Cognitive impairment is one of the frequent symptoms, exerting severe impact in patients' quality of life and school performances. The underlying pathogenic mechanisms are not fully understood, and molecular markers predictive of cognitive dysfunctions need to be identified. On these grounds, we searched for molecular signature/s (i.e., miRNAs and target genes) associated with cognitive impairment in a selected population of PedMS patients. Additionally, changes of their regional brain volumes associated with the miRNAs of interest were investigated. METHODS Nineteen PedMS subjects received a full cognitive evaluation; total RNA from peripheral blood samples was processed by next-generation sequencing followed by a bioinformatics/biostatistics analysis. RESULTS The expression of 11 miRNAs significantly correlated with the scores obtained at different cognitive tests; among the others, eight miRNAs correlated with the Trail Making Tests. The computational target prediction identified 337 genes targeted by the miRNAs of interest; a tangled network of molecular connections was hypothesized, where genes like BST1, NTNG2, SPTB, and STAB1, already associated with cognitive dysfunctions, were nodes of the net. Furthermore, the expression of some miRNAs significantly correlated with cerebral volumes, for example, four miRNAs with the cerebellum cortex. CONCLUSIONS As far as we know, this is the first evaluation exploring miRNAs in the cognitive performances of PedMS. Although none of these results survived the multiple tests' corrections, we believe that they may represent a step forward the identification of biomarkers useful for monitoring and targeting the onset/progression of cognitive impairments in MS.
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Affiliation(s)
- Maria Liguori
- National Research CouncilBari UnitInstitute of Biomedical TechnologiesBariItaly
| | - Nicoletta Nuzziello
- National Research CouncilBari UnitInstitute of Biomedical TechnologiesBariItaly
| | - Marta Simone
- Unit for Severe Disabilities in Developmental Age and Young Adults, Developmental Neurology and NeurorehabilitationScientific Institute IRCCS E. MedeaBrindisiItaly
- Department of Basic Sciences, Neurosciences and Sense OrgansUniversity of BariBariItaly
| | - Nicola Amoroso
- Dipartimento Interateneo di Fisica “M. Merlin”Università degli studi di Bari “A. Moro”BariItaly
- Istituto Nazionale di Fisica Nucleare, Sezione di BariBariItaly
| | - Rosa Gemma Viterbo
- Department of Basic Sciences, Neurosciences and Sense OrgansUniversity of BariBariItaly
| | - Sabina Tangaro
- Istituto Nazionale di Fisica Nucleare, Sezione di BariBariItaly
| | - Arianna Consiglio
- National Research CouncilBari UnitInstitute of Biomedical TechnologiesBariItaly
| | - Paola Giordano
- General Paediatric Unit “B. Trambusti”, Azienda Policlinico‐Giovanni XXIIIUniversity of BariBariItaly
| | - Roberto Bellotti
- Dipartimento Interateneo di Fisica “M. Merlin”Università degli studi di Bari “A. Moro”BariItaly
- Istituto Nazionale di Fisica Nucleare, Sezione di BariBariItaly
| | - Maria Trojano
- Department of Basic Sciences, Neurosciences and Sense OrgansUniversity of BariBariItaly
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Hamada S, Ohtsuka T. CAST: Its molecular structure and phosphorylation-dependent regulation of presynaptic plasticity. Neurosci Res 2018; 127:25-32. [DOI: 10.1016/j.neures.2017.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/05/2017] [Accepted: 12/06/2017] [Indexed: 11/16/2022]
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15
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Mahadevan V, Khademullah CS, Dargaei Z, Chevrier J, Uvarov P, Kwan J, Bagshaw RD, Pawson T, Emili A, De Koninck Y, Anggono V, Airaksinen M, Woodin MA. Native KCC2 interactome reveals PACSIN1 as a critical regulator of synaptic inhibition. eLife 2017; 6:e28270. [PMID: 29028184 PMCID: PMC5640428 DOI: 10.7554/elife.28270] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 09/08/2017] [Indexed: 01/01/2023] Open
Abstract
KCC2 is a neuron-specific K+-Cl- cotransporter essential for establishing the Cl- gradient required for hyperpolarizing inhibition in the central nervous system (CNS). KCC2 is highly localized to excitatory synapses where it regulates spine morphogenesis and AMPA receptor confinement. Aberrant KCC2 function contributes to human neurological disorders including epilepsy and neuropathic pain. Using functional proteomics, we identified the KCC2-interactome in the mouse brain to determine KCC2-protein interactions that regulate KCC2 function. Our analysis revealed that KCC2 interacts with diverse proteins, and its most predominant interactors play important roles in postsynaptic receptor recycling. The most abundant KCC2 interactor is a neuronal endocytic regulatory protein termed PACSIN1 (SYNDAPIN1). We verified the PACSIN1-KCC2 interaction biochemically and demonstrated that shRNA knockdown of PACSIN1 in hippocampal neurons increases KCC2 expression and hyperpolarizes the reversal potential for Cl-. Overall, our global native-KCC2 interactome and subsequent characterization revealed PACSIN1 as a novel and potent negative regulator of KCC2.
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Affiliation(s)
- Vivek Mahadevan
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
| | | | - Zahra Dargaei
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
| | - Jonah Chevrier
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
| | - Pavel Uvarov
- Department of Anatomy, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Julian Kwan
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular ResearchUniversity of TorontoTorontoCanada
| | - Richard D Bagshaw
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
| | - Tony Pawson
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
| | - Andrew Emili
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular ResearchUniversity of TorontoTorontoCanada
| | - Yves De Koninck
- Institut Universitaire en Santé Mentale de QuébecQuébecCanada
- Department of Psychiatry and NeuroscienceUniversité LavalQuébecCanada
| | - Victor Anggono
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia ResearchThe University of QueenslandBrisbaneAustralia
| | - Matti Airaksinen
- Department of Anatomy, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Melanie A Woodin
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
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Abstract
Synaptic connections in the brain are continuously weakened or strengthened in response to changes in neuronal activity. This process, known as synaptic plasticity, is the cellular basis for learning and memory, and is thought to be altered in several neuronal disorders. An important aspect of synaptic plasticity is the tightly controlled trafficking and synaptic targeting of the AMPA-type glutamate receptors, which are the major mediators of fast excitatory transmission in the brain. This review addresses the role of Rab GTPases in AMPA receptor trafficking in neurons under basal conditions and during activity-induced synaptic plasticity, especially during long-term potentiation (LTP) and long-term depression (LTD). We highlight the importance of the tight spatio-temporal control of Rab activity and suggest that this is critical for proper neuronal functions. We also discuss how abnormal AMPA receptor trafficking and malfunctioning of Rabs can lead to neurologic disorders or memory problems.
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Affiliation(s)
- Angelika Hausser
- Institute of Cell Biology and Immunology, University of Stuttgart , Stuttgart , Germany.,Stuttgart Research Center Systems Biology, University of Stuttgart , Stuttgart , Germany
| | - Katalin Schlett
- Department of Physiology and Neurobiology, Eötvös Loránd University , Budapest , Hungary.,MTA-ELTE NAP B Neuronal Cell Biology Research Group, Eötvös Loránd University , Budapest , Hungary
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Unique versus Redundant Functions of Neuroligin Genes in Shaping Excitatory and Inhibitory Synapse Properties. J Neurosci 2017; 37:6816-6836. [PMID: 28607166 DOI: 10.1523/jneurosci.0125-17.2017] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 05/10/2017] [Accepted: 05/31/2017] [Indexed: 11/21/2022] Open
Abstract
Neuroligins are evolutionarily conserved postsynaptic cell adhesion molecules that interact with presynaptic neurexins. Neurons express multiple neuroligin isoforms that are targeted to specific synapses, but their synaptic functions and mechanistic redundancy are not completely understood. Overexpression or RNAi-mediated knockdown of neuroligins, respectively, causes a dramatic increase or decrease in synapse density, whereas genetic deletions of neuroligins impair synapse function with only minor effects on synapse numbers, raising fundamental questions about the overall physiological role of neuroligins. Here, we have systematically analyzed the effects of conditional genetic deletions of all major neuroligin isoforms (i.e., NL1, NL2, and NL3), either individually or in combinations, in cultured mouse hippocampal and cortical neurons. We found that conditional genetic deletions of neuroligins caused no change or only a small change in synapses numbers, but strongly impaired synapse function. This impairment was isoform specific, suggesting that neuroligins are not functionally redundant. Sparse neuroligin deletions produced phenotypes comparable to those of global deletions, indicating that neuroligins function in a cell-autonomous manner. Mechanistically, neuroligin deletions decreased the synaptic levels of neurotransmitter receptors and had no effect on presynaptic release probabilities. Overexpression of neuroligin-1 in control or neuroligin-deficient neurons increased synaptic transmission and synapse density but not spine numbers, suggesting that these effects reflect a gain-of-function mechanism; whereas overexpression of neuroligin-3, which, like neuroligin-1 is also targeted to excitatory synapses, had no comparable effect. Our data demonstrate that neuroligins are required for the physiological organization of neurotransmitter receptors in postsynaptic specializations and suggest that they do not play a major role in synapse formation.SIGNIFICANCE STATEMENT Human neuroligin genes have been associated with autism, but the cellular functions of different neuroligins and their molecular mechanisms remain incompletely understood. Here, we performed comparative analyses in cultured mouse neurons of all major neuroligin isoforms, either individually or in combinations, using conditional knockouts. We found that neuroligin deletions did not affect synapse numbers but differentially impaired excitatory or inhibitory synaptic functions in an isoform-specific manner. These impairments were due, at least in part, to a decrease in synaptic distribution of neurotransmitter receptors upon deletion of neuroligins. Conversely, the overexpression of neuroligin-1 increased synapse numbers but not spine numbers. Our results suggest that various neuroligin isoforms perform unique postsynaptic functions in organizing synapses but are not essential for synapse formation or maintenance.
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Suzuki M, Kimura T. Microtubule-associated tau contributes to intra-dendritic trafficking of AMPA receptors in multiple ways. Neurosci Lett 2017; 653:276-282. [PMID: 28554859 DOI: 10.1016/j.neulet.2017.05.056] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/23/2017] [Accepted: 05/24/2017] [Indexed: 01/06/2023]
Abstract
Microtubule-associated protein tau has crucial roles not only in the formation of some neurodegenerative disorders but also in normal synaptic functions, although its contributions to these are still unclear. Here, to reveal the influence of tau deletion on trafficking of synaptic receptors, we investigated the distribution of GluA2-containing AMPA-type glutamate receptors (AMPARs) within neuronal dendrites in wild-type and tau-deficient neurons using biochemical and laser-confocal imaging techniques. Under basal conditions, expression of GluA2 at tau-deficient synapses was almost normal; however, its level within dendrites in tau-deficient neurons was greater than that in wild-type neurons. After NMDA treatment, a decrease in GluA2-containing AMPARs at synapses was observed in wild-type neurons, but not in tau-deficient neurons. Single-cell imaging of GluA2 within dendrites demonstrated that wild-type neurons, but not tau-deficient neurons, showed enlargement of GluA2 puncta. Interestingly, we also found that NMDA rapidly reduced the number of GluA2 puncta without changing their size in tau-deficient neurons but not wild-type neurons. These results demonstrate the multiple contributions of tau to the maintenance of dynamic AMPAR trafficking within dendrites during both stimulated and unstimulated conditions.
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Affiliation(s)
- Mamiko Suzuki
- Department of Aging Neurobiology, National Center for Geriatrics and Gerontology, Obu-shi, Aichi, Japan
| | - Tetsuya Kimura
- Department of Aging Neurobiology, National Center for Geriatrics and Gerontology, Obu-shi, Aichi, Japan; Department of Alzheimer's Disease Research, National Center for Geriatrics and Gerontology, Obu-shi, Aichi, Japan.
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Yang X, Pei J, Kaeser-Woo YJ, Bacaj T, Grishin NV, Südhof TC. Evolutionary conservation of complexins: from choanoflagellates to mice. EMBO Rep 2015; 16:1308-17. [PMID: 26338476 DOI: 10.15252/embr.201540305] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Accepted: 08/11/2015] [Indexed: 11/09/2022] Open
Abstract
Complexins are synaptic SNARE complex-binding proteins that cooperate with synaptotagmins in activating Ca(2+)-stimulated, synaptotagmin-dependent synaptic vesicle exocytosis and in clamping spontaneous, synaptotagmin-independent synaptic vesicle exocytosis. Here, we show that complexin sequences are conserved in some non-metazoan unicellular organisms and in all metazoans, suggesting that complexins are a universal feature of metazoans that predate metazoan evolution. We show that complexin from Nematostella vectensis, a cnidarian sea anemone far separated from mammals in metazoan evolution, functionally replaces mouse complexins in activating Ca(2+)-triggered exocytosis, but is unable to clamp spontaneous exocytosis. Thus, the activating function of complexins is likely conserved throughout metazoan evolution.
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Affiliation(s)
- Xiaofei Yang
- Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute Stanford University School of Medicine, Stanford, CA, USA College of Biomedical Engineering, South-Central University for Nationalities, Wuhan, China
| | - Jimin Pei
- Department of Biophysics, Howard Hughes Medical Institute University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yea Jin Kaeser-Woo
- Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute Stanford University School of Medicine, Stanford, CA, USA
| | - Taulant Bacaj
- Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute Stanford University School of Medicine, Stanford, CA, USA
| | - Nick V Grishin
- Department of Biophysics, Howard Hughes Medical Institute University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute Stanford University School of Medicine, Stanford, CA, USA
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