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Szymanowicz O, Drużdż A, Słowikowski B, Pawlak S, Potocka E, Goutor U, Konieczny M, Ciastoń M, Lewandowska A, Jagodziński PP, Kozubski W, Dorszewska J. A Review of the CACNA Gene Family: Its Role in Neurological Disorders. Diseases 2024; 12:90. [PMID: 38785745 PMCID: PMC11119137 DOI: 10.3390/diseases12050090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 04/25/2024] [Accepted: 04/28/2024] [Indexed: 05/25/2024] Open
Abstract
Calcium channels are specialized ion channels exhibiting selective permeability to calcium ions. Calcium channels, comprising voltage-dependent and ligand-gated types, are pivotal in neuronal function, with their dysregulation is implicated in various neurological disorders. This review delves into the significance of the CACNA genes, including CACNA1A, CACNA1B, CACNA1C, CACNA1D, CACNA1E, CACNA1G, and CACNA1H, in the pathogenesis of conditions such as migraine, epilepsy, cerebellar ataxia, dystonia, and cerebellar atrophy. Specifically, variants in CACNA1A have been linked to familial hemiplegic migraine and epileptic seizures, underscoring its importance in neurological disease etiology. Furthermore, different genetic variants of CACNA1B have been associated with migraine susceptibility, further highlighting the role of CACNA genes in migraine pathology. The complex relationship between CACNA gene variants and neurological phenotypes, including focal seizures and ataxia, presents a variety of clinical manifestations of impaired calcium channel function. The aim of this article was to explore the role of CACNA genes in various neurological disorders, elucidating their significance in conditions such as migraine, epilepsy, and cerebellar ataxias. Further exploration of CACNA gene variants and their interactions with molecular factors, such as microRNAs, holds promise for advancing our understanding of genetic neurological disorders.
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Affiliation(s)
- Oliwia Szymanowicz
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Artur Drużdż
- Department of Neurology, Municipal Hospital in Poznan, 61-285 Poznan, Poland;
| | - Bartosz Słowikowski
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (B.S.); (P.P.J.)
| | - Sandra Pawlak
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Ewelina Potocka
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Ulyana Goutor
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Mateusz Konieczny
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Małgorzata Ciastoń
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Aleksandra Lewandowska
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
| | - Paweł P. Jagodziński
- Department of Biochemistry and Molecular Biology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (B.S.); (P.P.J.)
| | - Wojciech Kozubski
- Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland;
| | - Jolanta Dorszewska
- Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, 61-701 Poznan, Poland; (O.S.); (S.P.); (E.P.); (U.G.); (M.K.); (M.C.); (A.L.)
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Eicher C, Marty B, Achermann P, Huber R, Landolt HP. Reduced subjective sleep quality in people rating themselves as electro-hypersensitive: An observational study. Sleep Med 2024; 113:165-171. [PMID: 38029625 DOI: 10.1016/j.sleep.2023.11.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 11/16/2023] [Accepted: 11/16/2023] [Indexed: 12/01/2023]
Abstract
BACKGROUND Disturbed sleep is among the most frequent health complaints of people exposed to radio frequency electromagnetic fields (RF-EMF) used in mobile telecommunication, particularly in individuals who consider themselves as EMF hypersensitive (EHS). We aimed at investigating whether the EHS status per se is associated with sleep complaints. Because allelic variants of the gene encoding the L-type, voltage-gated calcium channel Cav1.2 (CACNA1C) were previously associated with sleep complaints reminiscent of those reported by EHS individuals, we also explored whether self-rated EHS status and sleep quality associate with these gene variants. METHODS A total of 2'040 participants (1'381 females) aged 18-30 years completed online, validated questionnaires on EMF sensitivity, subjective sleep quality, daytime sleepiness, mentation during sleep, and diurnal preference. They also provided a saliva sample for genotyping three functional variants of CACNA1C (rs7304986, rs16929277 and rs2302729). Eligible participants endorsing the question "Are you electro-hypersensitive?" were considered as "EHS" (n = 105), those denying this question yet believing to develop detrimental health symptoms due to prevailing electromagnetic pollution as "attributers" (n = 254), and the remaining participants as "non-EHS" (n = 1'406). We combined the EHS and attributers into one group for binary analyses. In exploratory analyses, we then tested possible associations between EMF sensitivity, subjective sleep variables and CACNA1C variants using linear and logistic regression. We used age, sex, level of education, presence of sleep disorders and habitual mobile phone use as covariates and corrected with Benjamini-Hochberg False Discovery Rate for multiple comparisons. RESULTS The EHS/attributers consistently reported prolonged sleep latency, reduced sleep quality, higher sleepiness and more nocturnal mentation when compared to non-EHS. Habitual mobile phone use was not associated with self-rated sleep latency and sleep quality scores. While the T-allele of variant rs2302729 of CACNA1C was associated with both, self-reported EMF sensitivity and reduced subjective sleep quality, we found no evidence for the hypothesis that EHS mediates impaired sleep quality via this allelic variant. CONCLUSIONS Irrespective of reported RF-EMF exposure, self-rated EHS/attributers rated subjective sleep quality worse than non-EHS individuals. TRIAL REGISTRATION Swiss National Clinical Trials Portal (SNCTP000002285) and ClinicalTrials.gov (NCT03074617).
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Affiliation(s)
- Corinne Eicher
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Benjamin Marty
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Peter Achermann
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland; Sleep & Health Zurich, University Center of Competence, University of Zurich, Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland; Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
| | - Reto Huber
- Sleep & Health Zurich, University Center of Competence, University of Zurich, Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland; Department of Child and Adolescent Psychiatry and Psychotherapy, University Hospital of Psychiatry Zurich, University of Zurich, Zurich, Switzerland; Child Development Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Hans-Peter Landolt
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland; Sleep & Health Zurich, University Center of Competence, University of Zurich, Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland; Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
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Weyrer C, Turecek J, Harrison B, Regehr WG. Introduction of synaptotagmin 7 promotes facilitation at the climbing fiber to Purkinje cell synapse. Cell Rep 2021; 36:109719. [PMID: 34551307 PMCID: PMC9152841 DOI: 10.1016/j.celrep.2021.109719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/29/2021] [Accepted: 08/25/2021] [Indexed: 11/15/2022] Open
Abstract
Synaptotagmin 7 (Syt7) is a high-affinity calcium sensor that is implicated in multiple aspects of synaptic transmission. Here, we study the influence of Syt7 on the climbing fiber (CF) to Purkinje cell (PC) synapse. We find that small facilitation and prominent calcium-dependent recovery from depression at this synapse do not rely on Syt7 and that Syt7 is not normally present in CFs. We expressed Syt7 in CFs to assess the consequences of introducing Syt7 to a synapse that normally lacks Syt7. Syt7 expression does not promote asynchronous release or accelerate recovery from depression. Syt7 decreases the excitatory postsynaptic current (EPSC) magnitude, consistent with a decrease in the initial probability of release (PR). Syt7 also increases synaptic facilitation to such a large extent that it could not arise solely as an indirect consequence of decreased PR. Thus, the primary consequence of Syt7 expression in CFs, which normally lack Syt7, is to promote synaptic facilitation.
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Affiliation(s)
- Christopher Weyrer
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA; Department of Physiology, Development, and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Josef Turecek
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Bailey Harrison
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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Wang CC, Weyrer C, Fioravante D, Kaeser PS, Regehr WG. Presynaptic Short-Term Plasticity Persists in the Absence of PKC Phosphorylation of Munc18-1. J Neurosci 2021; 41:7329-7339. [PMID: 34290081 PMCID: PMC8412997 DOI: 10.1523/jneurosci.0347-21.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 07/03/2021] [Accepted: 07/09/2021] [Indexed: 12/22/2022] Open
Abstract
Post-tetanic potentiation (PTP) is a form of short-term plasticity that lasts for tens of seconds following a burst of presynaptic activity. It has been proposed that PTP arises from protein kinase C (PKC) phosphorylation of Munc18-1, an SM (Sec1/Munc-18 like) family protein that is essential for release. To test this model, we made a knock-in mouse in which all Munc18-1 PKC phosphorylation sites were eliminated through serine-to-alanine point mutations (Munc18-1SA mice), and we studied mice of either sex. The expression of Munc18-1 was not altered in Munc18-1SA mice, and there were no obvious behavioral phenotypes. At the hippocampal CA3-to-CA1 synapse and the granule cell parallel fiber (PF)-to-Purkinje cell (PC) synapse, basal transmission was largely normal except for small decreases in paired-pulse facilitation that are consistent with a slight elevation in release probability. Phorbol esters that mimic the activation of PKC by diacylglycerol still increased synaptic transmission in Munc18-1SA mice. In Munc18-1SA mice, 70% of PTP remained at CA3-to-CA1 synapses, and the amplitude of PTP was not reduced at PF-to-PC synapses. These findings indicate that at both CA3-to-CA1 and PF-to-PC synapses, phorbol esters and PTP enhance synaptic transmission primarily by mechanisms that are independent of PKC phosphorylation of Munc18-1.SIGNIFICANCE STATEMENT A leading mechanism for a prevalent form of short-term plasticity, post-tetanic potentiation (PTP), involves protein kinase C (PKC) phosphorylation of Munc18-1. This study tests this mechanism by creating a knock-in mouse in which Munc18-1 is replaced by a mutated form of Munc18-1 that cannot be phosphorylated. The main finding is that most PTP at hippocampal CA3-to-CA1 synapses or at cerebellar granule cell-to-Purkinje cell synapses does not rely on PKC phosphorylation of Munc18-1. Thus, mechanisms independent of PKC phosphorylation of Munc18-1 are important mediators of PTP.
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Affiliation(s)
- Chih-Chieh Wang
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Christopher Weyrer
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
- Department of Physiology, Development, and Neuroscience, University of Cambridge, Cambridge CB2 3EG, United Kingdom
| | - Diasynou Fioravante
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Pascal S Kaeser
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
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The potassium channel subunit K vβ1 serves as a major control point for synaptic facilitation. Proc Natl Acad Sci U S A 2020; 117:29937-29947. [PMID: 33168717 PMCID: PMC7703594 DOI: 10.1073/pnas.2000790117] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Nerve terminals generally engage in two opposite and essential forms of synaptic plasticity (facilitation or depression) that play critical roles in learning and memory. While the molecular components of both types of terminals are similar with regards to vesicle fusion, much less is known about their molecular control of electrical signaling. Measurements of the electrical impulses (action potentials) underlying these two forms of plasticity have been difficult in small nerve terminals due to their size. In this study we deployed optical physiology measurements to overcome this size barrier. Here, we identify a unique mechanism (Kvβ1 subunit) that enables broadening of the presynaptic action potentials that selectively supports synaptic facilitation, but does not alter any other aspects of nerve terminal function. Analysis of the presynaptic action potential’s (APsyn) role in synaptic facilitation in hippocampal pyramidal neurons has been difficult due to size limitations of axons. We overcame these size barriers by combining high-resolution optical recordings of membrane potential, exocytosis, and Ca2+ in cultured hippocampal neurons. These recordings revealed a critical and selective role for Kv1 channel inactivation in synaptic facilitation of excitatory hippocampal neurons. Presynaptic Kv1 channel inactivation was mediated by the Kvβ1 subunit and had a surprisingly rapid onset that was readily apparent even in brief physiological stimulation paradigms including paired-pulse stimulation. Genetic depletion of Kvβ1 blocked all broadening of the APsyn during high-frequency stimulation and eliminated synaptic facilitation without altering the initial probability of vesicle release. Thus, using all quantitative optical measurements of presynaptic physiology, we reveal a critical role for presynaptic Kv channels in synaptic facilitation at presynaptic terminals of the hippocampus upstream of the exocytic machinery.
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Chakouri N, Diaz J, Yang PS, Ben-Johny M. Ca V channels reject signaling from a second CaM in eliciting Ca 2+-dependent feedback regulation. J Biol Chem 2020; 295:14948-14962. [PMID: 32820053 DOI: 10.1074/jbc.ra120.013777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/18/2020] [Indexed: 11/06/2022] Open
Abstract
Calmodulin (CaM) regulation of voltage-gated calcium (CaV1-2) channels is a powerful Ca2+-feedback mechanism to adjust channel activity in response to Ca2+ influx. Despite progress in resolving mechanisms of CaM-CaV feedback, the stoichiometry of CaM interaction with CaV channels remains ambiguous. Functional studies that tethered CaM to CaV1.2 suggested that a single CaM sufficed for Ca2+ feedback, yet biochemical, FRET, and structural studies showed that multiple CaM molecules interact with distinct interfaces within channel cytosolic segments, suggesting that functional Ca2+ regulation may be more nuanced. Resolving this ambiguity is critical as CaM is enriched in subcellular domains where CaV channels reside, such as the cardiac dyad. We here localized multiple CaMs to the CaV nanodomain by tethering either WT or mutant CaM that lack Ca2+-binding capacity to the pore-forming α-subunit of CaV1.2, CaV1.3, and CaV2.1 and/or the auxiliary β2A subunit. We observed that a single CaM tethered to either the α or β2A subunit tunes Ca2+ regulation of CaV channels. However, when multiple CaMs are localized concurrently, CaV channels preferentially respond to signaling from the α-subunit-tethered CaM. Mechanistically, the introduction of a second IQ domain to the CaV1.3 carboxyl tail switched the apparent functional stoichiometry, permitting two CaMs to mediate functional regulation. In all, Ca2+ feedback of CaV channels depends exquisitely on a single CaM preassociated with the α-subunit carboxyl tail. Additional CaMs that colocalize with the channel complex are unable to trigger Ca2+-dependent feedback of channel gating but may support alternate regulatory functions.
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Affiliation(s)
- Nourdine Chakouri
- Department of Physiology and Cellular Biophysics, Columbia University, New York, New York, USA
| | - Johanna Diaz
- Department of Physiology and Cellular Biophysics, Columbia University, New York, New York, USA
| | - Philemon S Yang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Manu Ben-Johny
- Department of Physiology and Cellular Biophysics, Columbia University, New York, New York, USA.
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Dhuriya YK, Sharma D. Neuronal Plasticity: Neuronal Organization is Associated with Neurological Disorders. J Mol Neurosci 2020; 70:1684-1701. [PMID: 32504405 DOI: 10.1007/s12031-020-01555-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/13/2020] [Indexed: 12/18/2022]
Abstract
Stimuli from stressful events, attention in the classroom, and many other experiences affect the functionality of the brain by changing the structure or reorganizing the connections between neurons and their communication. Modification of the synaptic transmission is a vital mechanism for generating neural activity via internal or external stimuli. Neuronal plasticity is an important driving force in neuroscience research, as it is the basic process underlying learning and memory and is involved in many other functions including brain development and homeostasis, sensorial training, and recovery from brain injury. Indeed, neuronal plasticity has been explored in numerous studies, but it is still not clear how neuronal plasticity affects the physiology and morphology of the brain. Thus, unraveling the molecular mechanisms of neuronal plasticity is essential for understanding the operation of brain functions. In this timeline review, we discuss the molecular mechanisms underlying different forms of synaptic plasticity and their association with neurodegenerative/neurological disorders as a consequence of alterations in neuronal plasticity.
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Affiliation(s)
- Yogesh Kumar Dhuriya
- Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR) Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Divakar Sharma
- Department of Biochemistry, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Tajganj, Agra, India. .,CRF, Mass Spectrometry Laboratory, Kusuma School of Biological Sciences (KSBS), Indian Institute of Technology-Delhi (IIT-D), Delhi, 110016, India.
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Thalhammer A, Jaudon F, Cingolani LA. Emerging Roles of Activity-Dependent Alternative Splicing in Homeostatic Plasticity. Front Cell Neurosci 2020; 14:104. [PMID: 32477067 PMCID: PMC7235277 DOI: 10.3389/fncel.2020.00104] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Accepted: 04/06/2020] [Indexed: 12/25/2022] Open
Abstract
Homeostatic plasticity refers to the ability of neuronal networks to stabilize their activity in the face of external perturbations. Most forms of homeostatic plasticity ultimately depend on changes in the expression or activity of ion channels and synaptic proteins, which may occur at the gene, transcript, or protein level. The most extensively investigated homeostatic mechanisms entail adaptations in protein function or localization following activity-dependent posttranslational modifications. Numerous studies have also highlighted how homeostatic plasticity can be achieved by adjusting local protein translation at synapses or transcription of specific genes in the nucleus. In comparison, little attention has been devoted to whether and how alternative splicing (AS) of pre-mRNAs underlies some forms of homeostatic plasticity. AS not only expands proteome diversity but also contributes to the spatiotemporal dynamics of mRNA transcripts. Prominent in the brain where it can be regulated by neuronal activity, it is a flexible process, tightly controlled by a multitude of factors. Given its extensive use and versatility in optimizing the function of ion channels and synaptic proteins, we argue that AS is ideally suited to achieve homeostatic control of neuronal output. We support this thesis by reviewing emerging evidence linking AS to various forms of homeostatic plasticity: homeostatic intrinsic plasticity, synaptic scaling, and presynaptic homeostatic plasticity. Further, we highlight the relevance of this connection for brain pathologies.
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Affiliation(s)
- Agnes Thalhammer
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia (IIT), Genoa, Italy.,IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Fanny Jaudon
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia (IIT), Genoa, Italy.,IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Lorenzo A Cingolani
- Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia (IIT), Genoa, Italy.,Department of Life Sciences, University of Trieste, Trieste, Italy
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Dolphin AC, Lee A. Presynaptic calcium channels: specialized control of synaptic neurotransmitter release. Nat Rev Neurosci 2020; 21:213-229. [PMID: 32161339 PMCID: PMC7873717 DOI: 10.1038/s41583-020-0278-2] [Citation(s) in RCA: 126] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2020] [Indexed: 11/09/2022]
Abstract
Chemical synapses are heterogeneous junctions formed between neurons that are specialized for the conversion of electrical impulses into the exocytotic release of neurotransmitters. Voltage-gated Ca2+ channels play a pivotal role in this process as they are the major conduits for the Ca2+ ions that trigger the fusion of neurotransmitter-containing vesicles with the presynaptic membrane. Alterations in the intrinsic function of these channels and their positioning within the active zone can profoundly alter the timing and strength of synaptic output. Advances in optical and electron microscopic imaging, structural biology and molecular techniques have facilitated recent breakthroughs in our understanding of the properties of voltage-gated Ca2+ channels that support their presynaptic functions. Here we examine the nature of these channels, how they are trafficked to and anchored within presynaptic boutons, and the mechanisms that allow them to function optimally in shaping the flow of information through neural circuits.
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Affiliation(s)
- Annette C Dolphin
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.
| | - Amy Lee
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA.
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Kawaguchi SY. Dynamic Factors for Transmitter Release at Small Presynaptic Boutons Revealed by Direct Patch-Clamp Recordings. Front Cell Neurosci 2019; 13:269. [PMID: 31249514 PMCID: PMC6582627 DOI: 10.3389/fncel.2019.00269] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 05/29/2019] [Indexed: 12/29/2022] Open
Abstract
Small size of an axon and presynaptic structures have hindered direct functional analysis of axonal signaling and transmitter release at presynaptic boutons in the central nervous system. However, recent technical advances in subcellular patch-clamp recordings and in fluorescent imagings are shedding light on the dynamic nature of axonal and presynaptic mechanisms. Here I summarize the functional design of an axon and presynaptic boutons, such as diversity and activity-dependent changes of action potential (AP) waveforms, Ca2+ influx, and kinetics of transmitter release, revealed by the technical tour de force of direct patch-clamp recordings and the leading-edge fluorescent imagings. I highlight the critical factors for dynamic modulation of transmitter release and presynaptic short-term plasticity.
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Affiliation(s)
- Shin-Ya Kawaguchi
- Society-Academia Collaboration for Innovation, Kyoto University, Kyoto, Japan.,Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan.,Institute for Advanced Study, Kyoto University, Kyoto, Japan
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