1
|
Mechanisms of Synaptic Vesicle Exo- and Endocytosis. Biomedicines 2022; 10:biomedicines10071593. [PMID: 35884898 PMCID: PMC9313035 DOI: 10.3390/biomedicines10071593] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 01/05/2023] Open
Abstract
Within 1 millisecond of action potential arrival at presynaptic terminals voltage-gated Ca2+ channels open. The Ca2+ channels are linked to synaptic vesicles which are tethered by active zone proteins. Ca2+ entrance into the active zone triggers: (1) the fusion of the vesicle and exocytosis, (2) the replenishment of the active zone with vesicles for incoming exocytosis, and (3) various types of endocytosis for vesicle reuse, dependent on the pattern of firing. These time-dependent vesicle dynamics are controlled by presynaptic Ca2+ sensor proteins, regulating active zone scaffold proteins, fusion machinery proteins, motor proteins, endocytic proteins, several enzymes, and even Ca2+ channels, following the decay of Ca2+ concentration after the action potential. Here, I summarize the Ca2+-dependent protein controls of synchronous and asynchronous vesicle release, rapid replenishment of the active zone, endocytosis, and short-term plasticity within 100 msec after the action potential. Furthermore, I discuss the contribution of active zone proteins to presynaptic plasticity and to homeostatic readjustment during and after intense activity, in addition to activity-dependent endocytosis.
Collapse
|
2
|
Silveirinha VC, Lin H, Tanifuji S, Mochida S, Cottrell GS, Cimarosti H, Stephens GJ. Ca V2.2 (N-type) voltage-gated calcium channels are activated by SUMOylation pathways. Cell Calcium 2021; 93:102326. [PMID: 33360835 DOI: 10.1016/j.ceca.2020.102326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 11/01/2020] [Accepted: 11/23/2020] [Indexed: 11/21/2022]
Abstract
SUMOylation is an important post-translational modification process involving covalent attachment of SUMO (Small Ubiquitin-like MOdifier) protein to target proteins. Here, we investigated the potential for SUMO-1 protein to modulate the function of the CaV2.2 (N-type) voltage-gated calcium channel (VGCC), a protein vital for presynaptic neurotransmitter release. Co-expression of SUMO-1, but not the conjugation-deficient mutant SUMO-1ΔGG, increased heterologously-expressed CaV2.2 Ca2+ current density, an effect potentiated by the conjugating enzyme Ubc9. Expression of sentrin-specific protease (SENP)-1 or Ubc9 alone, had no effect on recombinant CaV2.2 channels. Co-expression of SUMO-1 and Ubc9 caused an increase in whole-cell maximal conductance (Gmax) and a hyperpolarizing shift in the midpoint of activation (V1/2). Mutation of all five CaV2.2 lysine residues to arginine within the five highest probability (>65 %) SUMOylation consensus motifs (SCMs) (construct CaV2.2-Δ5KR), produced a loss-of-function mutant. Mutagenesis of selected individual lysine residues identified K394, but not K951, as a key residue for SUMO-1-mediated increase in CaV2.2 Ca2+ current density. In synaptically-coupled superior cervical ganglion (SCG) neurons, SUMO-1 protein was distributed throughout the cell body, axons and dendrites and presumptive presynaptic terminals, whilst SUMO-1ΔGG protein was largely confined to the cell body, in particular, the nucleus. SUMO-1 expression caused increases in paired excitatory postsynaptic potential (EPSP) ratio at short (20-120 ms) inter-stimuli intervals in comparison to SUMO-1ΔGG, consistent with an increase in residual presynaptic Ca2+ current and an increase in release probability of synaptic vesicles. Together, these data provide evidence for CaV2.2 VGCCs as novel targets for SUMOylation pathways.
Collapse
Affiliation(s)
- Vasco C Silveirinha
- School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AJ, UK
| | - Hong Lin
- School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AJ, UK
| | - Shota Tanifuji
- Dept of Physiology, Tokyo Medical University, Tokyo, Japan
| | - Sumiko Mochida
- Dept of Physiology, Tokyo Medical University, Tokyo, Japan
| | - Graeme S Cottrell
- School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AJ, UK
| | - Helena Cimarosti
- School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AJ, UK.
| | - Gary J Stephens
- School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AJ, UK.
| |
Collapse
|
3
|
Liu D, Zhuang Y, Zhang L, Gao H, Neavin D, Carrillo-Roa T, Wang Y, Yu J, Qin S, Kim DC, Liu E, Nguyen TTL, Biernacka JM, Kaddurah-Daouk R, Dunlop BW, Craighead WE, Mayberg HS, Binder EB, Frye MA, Wang L, Weinshilboum RM. ERICH3: vesicular association and antidepressant treatment response. Mol Psychiatry 2021; 26:2415-2428. [PMID: 33230203 PMCID: PMC8141066 DOI: 10.1038/s41380-020-00940-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 09/30/2020] [Accepted: 10/26/2020] [Indexed: 01/22/2023]
Abstract
Selective serotonin reuptake inhibitors (SSRIs) are standard of care for major depressive disorder (MDD) pharmacotherapy, but only approximately half of these patients remit on SSRI therapy. Our previous genome-wide association study identified a single-nucleotide polymorphism (SNP) signal across the glutamate-rich 3 (ERICH3) gene that was nearly genome-wide significantly associated with plasma serotonin (5-HT) concentrations, which were themselves associated with SSRI response for MDD patients enrolled in the Mayo Clinic PGRN-AMPS SSRI trial. In this study, we performed a meta-analysis which demonstrated that those SNPs were significantly associated with SSRI treatment outcomes in four independent MDD trials. However, the function of ERICH3 and molecular mechanism(s) by which it might be associated with plasma 5-HT concentrations and SSRI clinical response remained unclear. Therefore, we characterized the human ERICH3 gene functionally and identified ERICH3 mRNA transcripts and protein isoforms that are highly expressed in central nervous system cells. Coimmunoprecipitation identified a series of ERICH3 interacting proteins including clathrin heavy chain which are known to play a role in vesicular function. Immunofluorescence showed ERICH3 colocalization with 5-HT in vesicle-like structures, and ERICH3 knock-out dramatically decreased 5-HT staining in SK-N-SH cells as well as 5-HT concentrations in the culture media and cell lysates without changing the expression of 5-HT synthesizing or metabolizing enzymes. Finally, immunofluorescence also showed ERICH3 colocalization with dopamine in human iPSC-derived neurons. These results suggest that ERICH3 may play a significant role in vesicular function in serotonergic and other neuronal cell types, which might help explain its association with antidepressant treatment response.
Collapse
Affiliation(s)
- Duan Liu
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Yongxian Zhuang
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA ,Present Address: Rubedo Life Sciences, Sunnyvale, CA USA
| | - Lingxin Zhang
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Huanyao Gao
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Drew Neavin
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA ,grid.415306.50000 0000 9983 6924Present Address: Centre for Cellular Genomics, Garvan Institute of Medical Research, Sydney, NSW Australia
| | - Tania Carrillo-Roa
- grid.419548.50000 0000 9497 5095Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Munich, Germany
| | - Yani Wang
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA ,grid.412262.10000 0004 1761 5538Xi’an No.1 Hospital, the First Affiliated Hospital of Northwest University, Xi’an, Shaanxi China ,Shaanxi Institute of Ophthalmology, Shaanxi Key Laboratory of Ophthalmology, Shaanxi Clinical Research Center for Ophthalmology Diseases, Xi’an, Shaanxi China
| | - Jia Yu
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Sisi Qin
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Daniel C. Kim
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Erica Liu
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Thanh Thanh Le Nguyen
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Joanna M. Biernacka
- grid.66875.3a0000 0004 0459 167XDepartment of Psychiatry and Psychology, Mayo Clinic, Rochester, MN USA ,grid.66875.3a0000 0004 0459 167XDepartment of Health Sciences Research, Mayo Clinic, Rochester, MN USA
| | - Rima Kaddurah-Daouk
- grid.26009.3d0000 0004 1936 7961Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC USA ,grid.26009.3d0000 0004 1936 7961Department of Medicine, Duke University, Durham, NC USA ,grid.26009.3d0000 0004 1936 7961Duke Institute for Brain Sciences, Duke University, Durham, NC USA
| | - Boadie W. Dunlop
- grid.189967.80000 0001 0941 6502Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA USA
| | - W. Edward Craighead
- grid.189967.80000 0001 0941 6502Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA USA
| | - Helen S. Mayberg
- grid.189967.80000 0001 0941 6502Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA USA ,grid.59734.3c0000 0001 0670 2351Departments of Neurology and Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - Elisabeth B. Binder
- grid.419548.50000 0000 9497 5095Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Munich, Germany ,grid.189967.80000 0001 0941 6502Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA USA
| | - Mark A. Frye
- grid.66875.3a0000 0004 0459 167XDepartment of Psychiatry and Psychology, Mayo Clinic, Rochester, MN USA
| | - Liewei Wang
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| | - Richard M. Weinshilboum
- grid.66875.3a0000 0004 0459 167XDivision of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN USA
| |
Collapse
|
4
|
Mochida S. Neurotransmitter Release Site Replenishment and Presynaptic Plasticity. Int J Mol Sci 2020; 22:ijms22010327. [PMID: 33396919 PMCID: PMC7794938 DOI: 10.3390/ijms22010327] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 12/23/2020] [Accepted: 12/27/2020] [Indexed: 12/19/2022] Open
Abstract
An action potential (AP) triggers neurotransmitter release from synaptic vesicles (SVs) docking to a specialized release site of presynaptic plasma membrane, the active zone (AZ). The AP simultaneously controls the release site replenishment with SV for sustainable synaptic transmission in response to incoming neuronal signals. Although many studies have suggested that the replenishment time is relatively slow, recent studies exploring high speed resolution have revealed SV dynamics with milliseconds timescale after an AP. Accurate regulation is conferred by proteins sensing Ca2+ entering through voltage-gated Ca2+ channels opened by an AP. This review summarizes how millisecond Ca2+ dynamics activate multiple protein cascades for control of the release site replenishment with release-ready SVs that underlie presynaptic short-term plasticity.
Collapse
Affiliation(s)
- Sumiko Mochida
- Department of Physiology, Tokyo Medical University, Tokyo 160-8402, Japan
| |
Collapse
|
5
|
Brawley J, Etter E, Heredia D, Intasiri A, Nennecker K, Smith J, Welcome BM, Brizendine RK, Gould TW, Bell TW, Cremo C. Synthesis and Evaluation of 4-Hydroxycoumarin Imines as Inhibitors of Class II Myosins. J Med Chem 2020; 63:11131-11148. [PMID: 32894018 PMCID: PMC8244571 DOI: 10.1021/acs.jmedchem.0c01062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Inhibitors of muscle myosin ATPases are needed to treat conditions that could be improved by promoting muscle relaxation. The lead compound for this study ((3-(N-butylethanimidoyl)ethyl)-4-hydroxy-2H-chromen-2-one; BHC) was previously discovered to inhibit skeletal myosin II. BHC and 34 analogues were synthesized to explore structure-activity relationships. The properties of analogues, including solubility, stability, and toxicity, suggest that the BHC scaffold may be useful for developing therapeutics. Inhibition of actin-activated ATPase activity of fast skeletal and cardiac muscle myosin II, inhibition of skeletal muscle contractility ex vivo, and slowing of in vitro actin-sliding velocity were measured. Several analogues with aromatic side arms showed improved potency (half-maximal inhibitory concentration (IC50) <1 μM) and selectivity (≥12-fold) for skeletal myosin versus cardiac myosin compared to BHC. Several analogues blocked neurotransmission, suggesting that they are selective for nonmuscle myosin II over skeletal myosin. Competition and molecular docking studies suggest that BHC and blebbistatin bind to the same site on myosin.
Collapse
Affiliation(s)
- Jhonnathan Brawley
- Department of Chemistry, University of Nevada, Reno, Nevada 89557-0216, United States
| | - Emily Etter
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0318, United States
| | - Dante Heredia
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0352, United States
| | - Amarawan Intasiri
- Department of Chemistry, University of Nevada, Reno, Nevada 89557-0216, United States
- Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Kyle Nennecker
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0318, United States
| | - Joshua Smith
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0318, United States
| | - Brandon M Welcome
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0318, United States
| | - Richard K Brizendine
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0318, United States
| | - Thomas W Gould
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0352, United States
| | - Thomas W Bell
- Department of Chemistry, University of Nevada, Reno, Nevada 89557-0216, United States
| | - Christine Cremo
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada 89557-0318, United States
| |
Collapse
|
6
|
Wagner W, Lippmann K, Heisler FF, Gromova KV, Lombino FL, Roesler MK, Pechmann Y, Hornig S, Schweizer M, Polo S, Schwarz JR, Eilers J, Kneussel M. Myosin VI Drives Clathrin-Mediated AMPA Receptor Endocytosis to Facilitate Cerebellar Long-Term Depression. Cell Rep 2019; 28:11-20.e9. [DOI: 10.1016/j.celrep.2019.06.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 05/01/2019] [Accepted: 05/31/2019] [Indexed: 11/30/2022] Open
|
7
|
Guzman GA, Guzman RE, Jordan N, Hidalgo P. A Tripartite Interaction Among the Calcium Channel α 1- and β-Subunits and F-Actin Increases the Readily Releasable Pool of Vesicles and Its Recovery After Depletion. Front Cell Neurosci 2019; 13:125. [PMID: 31130843 PMCID: PMC6509170 DOI: 10.3389/fncel.2019.00125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 03/13/2019] [Indexed: 11/13/2022] Open
Abstract
Neurotransmitter release is initiated by the influx of Ca2+via voltage-gated calcium channels. The accessory β-subunit (CaVβ) of these channels shapes synaptic transmission by associating with the pore-forming subunit (CaVα1) and up-regulating presynaptic calcium currents. Besides CaVα1, CaVβ interacts with several partners including actin filaments (F-actin). These filaments are known to associate with synaptic vesicles (SVs) at the presynaptic terminals and support their translocation within different pools, but the role of CaVβ/F-actin association on synaptic transmission has not yet been explored. We here study how CaVβ4, the major calcium channel β isoform in mamalian brain, modifies synaptic transmission in concert with F-actin in cultured hippocampal neurons. We analyzed the effect of exogenous CaVβ4 before and after pharmacological disruption of the actin cytoskeleton and dissected calcium channel-dependent and -independent functions by comparing the effects of the wild-type subunit with the one bearing a double mutation that impairs binding to CaVα1. We found that exogenously expressed wild-type CaVβ4 enhances spontaneous and depolarization-evoked excitatory postsynaptic currents (EPSCs) without altering synaptogenesis. CaVβ4 increases the size of the readily releasable pool (RRP) of SVs at resting conditions and accelerates their recovery after depletion. The enhanced neurotransmitter release induced by CaVβ4 is abolished upon disruption of the actin cytoskeleton. The CaVα1 association-deficient CaVβ4 mutant associates with actin filaments, but neither alters postsynaptic responses nor the time course of the RRP recovery. Furthermore, this mutant protein preserves the ability to increase the RRP size. These results indicate that the interplay between CaVβ4 and F-actin also support the recruitment of SVs to the RRP in a CaVα1-independent manner. Our studies show an emerging role of CaVβ in determining SV maturation toward the priming state and its replenishment after release. We envision that this subunit plays a role in coupling exocytosis to endocytosis during the vesicle cycle.
Collapse
Affiliation(s)
- Gustavo A Guzman
- Institute of Complex Systems 4, Zelluläre Biophysik, Forschungszentrum Jülich, Jülich, Germany
| | - Raul E Guzman
- Institute of Complex Systems 4, Zelluläre Biophysik, Forschungszentrum Jülich, Jülich, Germany
| | - Nadine Jordan
- Institute of Complex Systems 4, Zelluläre Biophysik, Forschungszentrum Jülich, Jülich, Germany
| | - Patricia Hidalgo
- Institute of Complex Systems 4, Zelluläre Biophysik, Forschungszentrum Jülich, Jülich, Germany.,Institute of Biochemistry, Heinrich-Heine University, Düsseldorf, Germany
| |
Collapse
|
8
|
Grigoryev PN, Khisamieva GA, Zefirov AL. Septin Polymerization Slows Synaptic Vesicle Recycling in Motor Nerve Endings. Acta Naturae 2019; 11:54-62. [PMID: 31413880 PMCID: PMC6643342 DOI: 10.32607/20758251-2019-11-2-54-62] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Indexed: 11/20/2022] Open
Abstract
Septins are GTP-binding proteins recognized as a component of the cytoskeleton. Despite the fact that septins are highly expressed by neurons and can interact with the proteins that participate in synaptic vesicle exocytosis and endocytosis, the role of septins in synaptic transmission and the synaptic vesicle recycling mechanisms is poorly understood. In this study, neurotransmitter release and synaptic vesicle exocytosis and endocytosis were investigated by microelectrode intracellular recording of end-plate potentials and fluorescent confocal microscopy in mouse diaphragm motor nerve endings during septin polymerization induced by forchlorfenuron application. It was shown that forchlorfenuron application reduces neurotransmission during prolonged high-frequency (20 and 50 pulses/s) stimulation. Application of pairs of short high-frequency stimulation trains showed that forchlorfenuron slows the replenishment of the readily releasable pool. Forchlorfenuron enhanced FM 1-43 fluorescent dye loading by synaptic vesicle endocytosis but decreased dye unloading from the preliminarily stained nerve endings by synaptic vesicle exocytosis. It was concluded that the septin polymerization induced by forchlorfenuron application slows the rate of synaptic vesicle recycling in motor nerve endings due to the impairment of synaptic vesicle transport.
Collapse
Affiliation(s)
- P. N. Grigoryev
- Kazan State Medical University, Butlerova Str. 49, Kazan, 420012, Russia
| | - G. A. Khisamieva
- Kazan State Medical University, Butlerova Str. 49, Kazan, 420012, Russia
| | - A. L. Zefirov
- Kazan State Medical University, Butlerova Str. 49, Kazan, 420012, Russia
| |
Collapse
|
9
|
Maschi D, Gramlich MW, Klyachko VA. Myosin V functions as a vesicle tether at the plasma membrane to control neurotransmitter release in central synapses. eLife 2018; 7:e39440. [PMID: 30320552 PMCID: PMC6209431 DOI: 10.7554/elife.39440] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 10/11/2018] [Indexed: 12/21/2022] Open
Abstract
Synaptic vesicle fusion occurs at specialized release sites at the active zone. How refilling of release sites with new vesicles is regulated in central synapses remains poorly understood. Using nanoscale-resolution detection of individual release events in rat hippocampal synapses we found that inhibition of myosin V, the predominant vesicle-associated motor, strongly reduced refilling of the release sites during repetitive stimulation. Single-vesicle tracking revealed that recycling vesicles continuously shuttle between a plasma membrane pool and an inner pool. Vesicle retention at the membrane pool was regulated by neural activity in a myosin V dependent manner. Ultrastructural measurements of vesicle occupancy at the plasma membrane together with analyses of single-vesicle trajectories during vesicle shuttling between the pools suggest that myosin V acts as a vesicle tether at the plasma membrane, rather than a motor transporting vesicles to the release sites, or directly regulating vesicle exocytosis.
Collapse
Affiliation(s)
- Dario Maschi
- Department of Cell Biology and PhysiologyWashington UniversityMissouriUnited States
- Department of Biomedical EngineeringWashington UniversityMissouriUnited States
| | - Michael W Gramlich
- Department of Cell Biology and PhysiologyWashington UniversityMissouriUnited States
- Department of Biomedical EngineeringWashington UniversityMissouriUnited States
| | - Vitaly A Klyachko
- Department of Cell Biology and PhysiologyWashington UniversityMissouriUnited States
- Department of Biomedical EngineeringWashington UniversityMissouriUnited States
| |
Collapse
|
10
|
SAD-B Phosphorylation of CAST Controls Active Zone Vesicle Recycling for Synaptic Depression. Cell Rep 2017; 16:2901-2913. [PMID: 27626661 DOI: 10.1016/j.celrep.2016.08.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 06/28/2016] [Accepted: 08/05/2016] [Indexed: 12/25/2022] Open
Abstract
Short-term synaptic depression (STD) is a common form of activity-dependent plasticity observed widely in the nervous system. Few molecular pathways that control STD have been described, but the active zone (AZ) release apparatus provides a possible link between neuronal activity and plasticity. Here, we show that an AZ cytomatrix protein CAST and an AZ-associated protein kinase SAD-B coordinately regulate STD by controlling reloading of the AZ with release-ready synaptic vesicles. SAD-B phosphorylates the N-terminal serine (S45) of CAST, and S45 phosphorylation increases with higher firing rate. A phosphomimetic CAST (S45D) mimics CAST deletion, which enhances STD by delaying reloading of the readily releasable pool (RRP), resulting in a pool size decrease. A phosphonegative CAST (S45A) inhibits STD and accelerates RRP reloading. Our results suggest that the CAST/SAD-B reaction serves as a brake on synaptic transmission by temporal calibration of activity and synaptic depression via RRP size regulation.
Collapse
|
11
|
Eich ML, Dembla E, Wahl S, Dembla M, Schwarz K, Schmitz F. The Calcineurin-Binding, Activity-Dependent Splice Variant Dynamin1xb Is Highly Enriched in Synapses in Various Regions of the Central Nervous System. Front Mol Neurosci 2017; 10:230. [PMID: 28790889 PMCID: PMC5524891 DOI: 10.3389/fnmol.2017.00230] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 07/06/2017] [Indexed: 12/22/2022] Open
Abstract
In the present study, we generated and characterized a splice site-specific monoclonal antibody that selectively detects the calcineurin-binding dynamin1 splice variant dynamin1xb. Calcineurin is a Ca2+-regulated phosphatase that enhances dynamin1 activity and is an important Ca2+-sensing mediator of homeostatic synaptic plasticity in neurons. Using this dynamin1xb-specific antibody, we found dynamin1xb highly enriched in synapses of all analyzed brain regions. In photoreceptor ribbon synapses, dynamin1xb was enriched in close vicinity to the synaptic ribbon in a manner indicative of a peri-active zone immunolabeling. Interestingly, in dark-adapted mice we observed an enhanced and selective enrichment of dynamin1xb in both synaptic layers of the retina in comparison to light-adapted mice. This could be due to an illumination-dependent recruitment of dynamin1xb to retinal synapses and/or due to a darkness-induced increase of dynamin1xb biosynthesis. These latter findings indicate that dynamin1xb is part of a versatile and highly adjustable, activity-regulated endocytic synaptic machinery.
Collapse
Affiliation(s)
- Marie-Lisa Eich
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Ekta Dembla
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Silke Wahl
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Mayur Dembla
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Karin Schwarz
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| | - Frank Schmitz
- Department of Neuroanatomy, Medical School Homburg/Saar, Institute for Anatomy and Cell Biology, Saarland UniversityHomburg/Saar, Germany
| |
Collapse
|
12
|
MOCHIDA S. Millisecond Ca 2+ dynamics activate multiple protein cascades for synaptic vesicle control. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2017; 93:802-820. [PMID: 29225307 PMCID: PMC5790758 DOI: 10.2183/pjab.93.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 08/21/2017] [Indexed: 06/07/2023]
Abstract
For reliable transmission at chemical synapses, neurotransmitters must be released dynamically in response to neuronal activity in the form of action potentials. Stable synaptic transmission is dependent on the efficacy of transmitter release and the rate of resupplying synaptic vesicles to their release sites. Accurate regulation is conferred by proteins sensing Ca2+ entering through voltage-gated Ca2+ channels opened by an action potential. Presynaptic Ca2+ concentration changes are dynamic functions in space and time, with wide fluctuations associated with different rates of neuronal activity. Thus, regulation of transmitter release includes reactions involving multiple Ca2+-dependent proteins, each operating over a specific time window. Classically, studies of presynaptic proteins function favored large invertebrate presynaptic terminals. I have established a useful mammalian synapse model based on sympathetic neurons in culture. This review summarizes the use of this model synapse to study the roles of presynaptic proteins in neuronal activity for the control of transmitter release efficacy and synaptic vesicle recycling.
Collapse
Affiliation(s)
- Sumiko MOCHIDA
- Department of Physiology, Tokyo Medical University, Tokyo, Japan
| |
Collapse
|
13
|
Grigoryev PN, Zefirov AL. Myosin accelerates synaptic vesicle recycling in the motor nerve endings. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2016; 470:217-219. [PMID: 27822755 DOI: 10.1134/s0012496616050112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Indexed: 11/23/2022]
Abstract
Neurotransmitter release and exocytosis of synaptic vesicles in the motor nerve endings of the frog cutaneous-pectoris muscle were studied using electrophysiological and optical methods under the conditions of inhibition of the myosin light-chain kinase and non-muscle myosin by the specific inhibitors ML-7 (12 μM) and (-)-blebbistatin (100 μM). At high-frequency stimulation (20 pulses/s), these inhibitors strengthened suppression of transmitter release during the first 20-25 s and slowed down the release of the fluorescent dye FM 1-43. The obtained results indicate that myosin accelerates rapid synaptic vesicle recycling upon high-frequency stimulation.
Collapse
Affiliation(s)
- P N Grigoryev
- Kazan State Medical University, Ministry of Health, Kazan, Tatarstan, Russia
| | - A L Zefirov
- Kazan State Medical University, Ministry of Health, Kazan, Tatarstan, Russia.
| |
Collapse
|
14
|
Miki T, Malagon G, Pulido C, Llano I, Neher E, Marty A. Actin- and Myosin-Dependent Vesicle Loading of Presynaptic Docking Sites Prior to Exocytosis. Neuron 2016; 91:808-823. [DOI: 10.1016/j.neuron.2016.07.033] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 05/17/2016] [Accepted: 07/11/2016] [Indexed: 10/21/2022]
|