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Andreyanov M, Heinrich R, Berlin S. Design of Ultrapotent Genetically Encoded Inhibitors of Kv4.2 for Gating Neural Plasticity. J Neurosci 2024; 44:e2295222023. [PMID: 38154956 PMCID: PMC10869153 DOI: 10.1523/jneurosci.2295-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 11/05/2023] [Accepted: 11/22/2023] [Indexed: 12/30/2023] Open
Abstract
The Kv4.2 potassium channel plays established roles in neuronal excitability, while also being implicated in plasticity. Current means to study the roles of Kv4.2 are limited, motivating us to design a genetically encoded membrane tethered Heteropodatoxin-2 (MetaPoda). We find that MetaPoda is an ultrapotent and selective gating-modifier of Kv4.2. We narrow its site of contact with the channel to two adjacent residues within the voltage sensitive domain (VSD) and, with docking simulations, suggest that the toxin binds the VSD from within the membrane. We also show that MetaPoda does not require an external linker of the channel for its activity. In neurons (obtained from female and male rat neonates), MetaPoda specifically, and potently, inhibits all Kv4 currents, leaving all other A-type currents unaffected. Inhibition of Kv4 in hippocampal neurons does not promote excessive excitability, as is expected from a simple potassium channel blocker. We do find that MetaPoda's prolonged expression (1 week) increases expression levels of the immediate early gene cFos and prevents potentiation. These findings argue for a major role of Kv4.2 in facilitating plasticity of hippocampal neurons. Lastly, we show that our engineering strategy is suitable for the swift engineering of another potent Kv4.2-selective membrane-tethered toxin, Phrixotoxin-1, denoted MetaPhix. Together, we provide two uniquely potent genetic tools to study Kv4.2 in neuronal excitability and plasticity.
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Affiliation(s)
- Michael Andreyanov
- Department of Neuroscience, Ruth and Bruce Rappaport Faculty of Medicine, Technion- Israel Institute of Technology, Haifa 3525433, Israel
| | - Ronit Heinrich
- Department of Neuroscience, Ruth and Bruce Rappaport Faculty of Medicine, Technion- Israel Institute of Technology, Haifa 3525433, Israel
| | - Shai Berlin
- Department of Neuroscience, Ruth and Bruce Rappaport Faculty of Medicine, Technion- Israel Institute of Technology, Haifa 3525433, Israel
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2
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Peretti D, Smith HL, Verity N, Humoud I, de Weerd L, Swinden DP, Hayes J, Mallucci GR. TrkB signaling regulates the cold-shock protein RBM3-mediated neuroprotection. Life Sci Alliance 2021; 4:4/4/e202000884. [PMID: 33563652 PMCID: PMC7893816 DOI: 10.26508/lsa.202000884] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 01/25/2021] [Accepted: 01/25/2021] [Indexed: 02/02/2023] Open
Abstract
Increasing levels of the cold-shock protein, RNA-binding motif 3 (RBM3), either through cooling or by ectopic over-expression, prevents synapse and neuronal loss in mouse models of neurodegeneration. To exploit this process therapeutically requires an understanding of mechanisms controlling cold-induced RBM3 expression. Here, we show that cooling increases RBM3 through activation of TrkB via PLCγ1 and pCREB signaling. RBM3, in turn, has a hitherto unrecognized negative feedback on TrkB-induced ERK activation through induction of its specific phosphatase, DUSP6. Thus, RBM3 mediates structural plasticity through a distinct, non-canonical activation of TrkB signaling, which is abolished in RBM3-null neurons. Both genetic reduction and pharmacological antagonism of TrkB and its downstream mediators abrogate cooling-induced RBM3 induction and prevent structural plasticity, whereas TrkB inhibition similarly prevents RBM3 induction and the neuroprotective effects of cooling in prion-diseased mice. Conversely, TrkB agonism induces RBM3 without cooling, preventing synapse loss and neurodegeneration. TrkB signaling is, therefore, necessary for the induction of RBM3 and related neuroprotective effects and provides a target by which RBM3-mediated synapse-regenerative therapies in neurodegenerative disorders can be used therapeutically without the need for inducing hypothermia.
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Affiliation(s)
- Diego Peretti
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | - Heather L Smith
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | - Nicholas Verity
- MRC Toxicology Unit at the University of Cambridge, Leicester, UK
| | - Ibrahim Humoud
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | - Lis de Weerd
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | - Dean P Swinden
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | - Joseph Hayes
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | - Giovanna R Mallucci
- UK Dementia Research Institute at the University of Cambridge and Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
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3
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Aceto G, Re A, Mattera A, Leone L, Colussi C, Rinaudo M, Scala F, Gironi K, Barbati SA, Fusco S, Green T, Laezza F, D'Ascenzo M, Grassi C. GSK3β Modulates Timing-Dependent Long-Term Depression Through Direct Phosphorylation of Kv4.2 Channels. Cereb Cortex 2020; 29:1851-1865. [PMID: 29790931 DOI: 10.1093/cercor/bhy042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 01/15/2018] [Accepted: 02/07/2018] [Indexed: 12/31/2022] Open
Abstract
Spike timing-dependent plasticity (STDP) is a form of activity-dependent remodeling of synaptic strength that underlies memory formation. Despite its key role in dictating learning rules in the brain circuits, the molecular mechanisms mediating STDP are still poorly understood. Here, we show that spike timing-dependent long-term depression (tLTD) and A-type K+ currents are modulated by pharmacological agents affecting the levels of active glycogen-synthase kinase 3 (GSK3) and by GSK3β knockdown in layer 2/3 of the mouse somatosensory cortex. Moreover, the blockade of A-type K+ currents mimics the effects of GSK3 up-regulation on tLTD and occludes further changes in synaptic strength. Pharmacological, immunohistochemical and biochemical experiments revealed that GSK3β influence over tLTD induction is mediated by direct phosphorylation at Ser-616 of the Kv4.2 subunit, a molecular determinant of A-type K+ currents. Collectively, these results identify the functional interaction between GSK3β and Kv4.2 channel as a novel mechanism for tLTD modulation providing exciting insight into the understanding of GSK3β role in synaptic plasticity.
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Affiliation(s)
- Giuseppe Aceto
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Agnese Re
- Institute of Cell Biology and Neurobiology, National Research Council, Rome, Italy
| | - Andrea Mattera
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Lucia Leone
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario A Gemelli, IRCCS, Rome, Italy
| | - Claudia Colussi
- Institute of Cell Biology and Neurobiology, National Research Council, Rome, Italy
| | - Marco Rinaudo
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Federico Scala
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Katia Gironi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | | | - Salvatore Fusco
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario A Gemelli, IRCCS, Rome, Italy
| | - Thomas Green
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA
| | - Fernanda Laezza
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA
| | - Marcello D'Ascenzo
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario A Gemelli, IRCCS, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario A Gemelli, IRCCS, Rome, Italy
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4
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Fernández-Fernández D, Lamas JA. Metabotropic Modulation of Potassium Channels During Synaptic Plasticity. Neuroscience 2020; 456:4-16. [PMID: 32114098 DOI: 10.1016/j.neuroscience.2020.02.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 02/14/2020] [Accepted: 02/18/2020] [Indexed: 01/06/2023]
Abstract
Besides their primary function mediating the repolarization phase of action potentials, potassium channels exquisitely and ubiquitously regulate the resting membrane potential of neurons and therefore have a key role establishing their intrinsic excitability. This group of proteins is composed of a very diverse collection of voltage-dependent and -independent ion channels, whose specific distribution is finely tuned at the level of the synapse. Both at the presynaptic and postsynaptic membranes, different types of potassium channels are subjected to modulation by second messenger signaling cascades triggered by metabotropic receptors, which in this way serve as a link between neurotransmitter actions and changes in the neuron membrane excitability. On the one hand, by regulating the resting membrane potential of the postsynaptic membrane, potassium channels appear to be critical towards setting the threshold for the induction of long-term potentiation and depression. On the other hand, these channels maintain the presynaptic membrane potential under control, therefore influencing the probability of neurotransmitter release underlying different forms of short-term plasticity. In the present review, we examine in detail the role of metabotropic receptors translating their activation by different neurotransmitters into a final effect modulating several types of potassium channels. Furthermore, we evaluate the consequences that this interplay has on the induction and maintenance of different forms of synaptic plasticity.
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Affiliation(s)
- D Fernández-Fernández
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, Vigo, Galicia, Spain.
| | - J A Lamas
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, Vigo, Galicia, Spain
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5
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Reward Devaluation Attenuates Cue-Evoked Sucrose Seeking and Is Associated with the Elimination of Excitability Differences between Ensemble and Non-ensemble Neurons in the Nucleus Accumbens. eNeuro 2019; 6:ENEURO.0338-19.2019. [PMID: 31699890 PMCID: PMC6905639 DOI: 10.1523/eneuro.0338-19.2019] [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: 08/14/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 11/21/2022] Open
Abstract
Animals must learn relationships between foods and the environmental cues that predict their availability for survival. Such cue–food associations are encoded in sparse sets of neurons or “neuronal ensembles” in the nucleus accumbens (NAc). For these ensemble-encoded, cue-controlled appetitive responses to remain adaptive, they must allow for their dynamic updating depending on acute changes in internal states such as physiological hunger or the perceived desirability of food. However, how these neuronal ensembles are recruited and physiologically modified following the update of such learned associations is unclear. To investigate this, we examined the effects of devaluation on ensemble plasticity at the levels of recruitment, intrinsic excitability, and synaptic physiology in sucrose-conditioned Fos-GFP mice that express green fluorescent protein (GFP) in recently activated neurons. Neuronal ensemble activation patterns and their physiology were examined using immunohistochemistry and slice electrophysiology, respectively. Reward-specific devaluation following 4 d of ad libitum sucrose consumption, but not general caloric devaluation, attenuated cue-evoked sucrose seeking. This suggests that changes in the hedonic and/or incentive value of sucrose, and not caloric need, drove this behavior. Moreover, devaluation attenuated the size of the neuronal ensemble recruited by the cue in the NAc shell. Finally, it eliminated the relative enhanced excitability of ensemble (GFP+) neurons against non-ensemble (GFP−) neurons observed under non-devalued conditions, and did not induce any ensemble-specific changes in excitatory synaptic physiology. Our findings provide new insights into neuronal ensemble mechanisms that underlie the changes in the incentive and/or hedonic impact of cues that support adaptive food seeking.
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Mao XW, Sandberg LB, Gridley DS, Herrmann EC, Zhang G, Raghavan R, Zubarev RA, Zhang B, Stodieck LS, Ferguson VL, Bateman TA, Pecaut MJ. Proteomic Analysis of Mouse Brain Subjected to Spaceflight. Int J Mol Sci 2018; 20:ijms20010007. [PMID: 30577490 PMCID: PMC6337482 DOI: 10.3390/ijms20010007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/11/2018] [Accepted: 12/17/2018] [Indexed: 01/01/2023] Open
Abstract
There is evidence that spaceflight poses acute and late risks to the central nervous system. To explore possible mechanisms, the proteomic changes following spaceflight in mouse brain were characterized. Space Shuttle Atlantis (STS-135) was launched from the Kennedy Space Center (KSC) on a 13-day mission. Within 3–5 h after landing, brain tissue was collected to evaluate protein expression profiles using quantitative proteomic analysis. Our results showed that there were 26 proteins that were significantly altered after spaceflight in the gray and/or white matter. While there was no overlap between the white and gray matter in terms of individual proteins, there was overlap in terms of function, synaptic plasticity, vesical activity, protein/organelle transport, and metabolism. Our data demonstrate that exposure to the spaceflight environment induces significant changes in protein expression related to neuronal structure and metabolic function. This might lead to a significant impact on brain structural and functional integrity that could affect the outcome of space missions.
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Affiliation(s)
- Xiao Wen Mao
- Department of Basic Sciences, Division of Biomedical Engineering Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA.
| | - Lawrence B Sandberg
- Department of Biochemistry, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
| | - Daila S Gridley
- Department of Basic Sciences, Division of Biomedical Engineering Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA.
| | - E Clifford Herrmann
- Department of Biochemistry, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
| | - Guangyu Zhang
- Department of Biochemistry, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
| | - Ravi Raghavan
- Department of Pathology and Human Anatomy, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
| | - Roman A Zubarev
- Department of Medical Biochemistry and Biophysics, Biomedicum, Karolinska Institutet, SE 17177 Stockholm, Sweden.
- Department of Pharmacological and Technological Chemistry, I.M. Sechenov First Moscow State Medical University, Moscow 119991, Russia.
| | - Bo Zhang
- Department of Medical Biochemistry and Biophysics, Biomedicum, Karolinska Institutet, SE 17177 Stockholm, Sweden.
- Department of Pharmacological and Technological Chemistry, I.M. Sechenov First Moscow State Medical University, Moscow 119991, Russia.
| | - Louis S Stodieck
- BioServe Space Technologies, University of Colorado at Boulder, Boulder, CO 80303, USA.
| | - Virginia L Ferguson
- BioServe Space Technologies, University of Colorado at Boulder, Boulder, CO 80303, USA.
| | - Ted A Bateman
- Department of Bioengineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Michael J Pecaut
- Department of Basic Sciences, Division of Biomedical Engineering Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA.
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7
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Rossetti T, Banerjee S, Kim C, Leubner M, Lamar C, Gupta P, Lee B, Neve R, Lisman J. Memory Erasure Experiments Indicate a Critical Role of CaMKII in Memory Storage. Neuron 2017; 96:207-216.e2. [PMID: 28957669 DOI: 10.1016/j.neuron.2017.09.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 07/24/2017] [Accepted: 09/11/2017] [Indexed: 12/29/2022]
Abstract
The abundant synaptic protein CaMKII is necessary for long-term potentiation (LTP) and memory. However, whether CaMKII is required only during initial processes or whether it also mediates memory storage remains unclear. The most direct test of a storage role is the erasure test. In this test, a putative memory molecule is inhibited after learning. The key prediction is that this should produce persistent memory erasure even after the inhibitory agent is removed. We conducted this test using transient viral (HSV) expression of dominant-negative CaMKII-alpha (K42M) in the hippocampus. This produced persistent erasure of conditioned place avoidance. As an additional test, we found that expression of activated CaMKII (T286D/T305A/T306A) impaired place avoidance, a result not expected if a process other than CaMKII stores memory. Our behavioral results, taken together with prior experiments on LTP, strongly support a critical role of CaMKII in LTP maintenance and memory storage.
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Affiliation(s)
- Tom Rossetti
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Somdeb Banerjee
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Chris Kim
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Megan Leubner
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Casey Lamar
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Pooja Gupta
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Bomsol Lee
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Rachael Neve
- Gene Delivery Technology Core, Department of Neurology, MGH, 65 Landsdowne Street, Cambridge, MA 02139, USA
| | - John Lisman
- Department of Biology, Brandeis University, 415 South Street, Waltham, MA 02453, USA.
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8
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Short SM, Oikonomou KD, Zhou WL, Acker CD, Popovic MA, Zecevic D, Antic SD. The stochastic nature of action potential backpropagation in apical tuft dendrites. J Neurophysiol 2017; 118:1394-1414. [PMID: 28566465 DOI: 10.1152/jn.00800.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 05/25/2017] [Accepted: 05/30/2017] [Indexed: 11/22/2022] Open
Abstract
In cortical pyramidal neurons, backpropagating action potentials (bAPs) supply Ca2+ to synaptic contacts on dendrites. To determine whether the efficacy of AP backpropagation into apical tuft dendrites is stable over time, we performed dendritic Ca2+ and voltage imaging in rat brain slices. We found that the amplitude of bAP-Ca2+ in apical tuft branches was unstable, given that it varied from trial to trial (termed "bAP-Ca2+ flickering"). Small perturbations in dendritic physiology, such as spontaneous synaptic inputs, channel inactivation, or temperature-induced changes in channel kinetics, can cause bAP flickering. In the tuft branches, the density of Na+ and K+ channels was sufficient to support local initiation of fast spikelets by glutamate iontophoresis. We quantified the time delay between the somatic AP burst and the peak of dendritic Ca2+ transient in the apical tuft, because this delay is important for induction of spike-timing dependent plasticity. Depending on the frequency of the somatic AP triplets, Ca2+ signals peaked in the apical tuft 20-50 ms after the 1st AP in the soma. Interestingly, at low frequency (<20 Hz), the Ca2+ peaked sooner than at high frequency, because only the 1st AP invaded tuft. Activation of dendritic voltage-gated Ca2+ channels is sensitive to the duration of the dendritic voltage transient. In apical tuft branches, small changes in the duration of bAP voltage waveforms cause disproportionately large increases in dendritic Ca2+ influx (bAP-Ca2+ flickering). The stochastic nature of bAP-Ca2+ adds a new perspective on the mechanisms by which pyramidal neurons combine inputs arriving at different cortical layers.NEW & NOTEWORTHY The bAP-Ca2+ signal amplitudes in some apical tuft branches randomly vary from moment to moment. In repetitive measurements, successful AP invasions are followed by complete failures. Passive spread of voltage from the apical trunk into the tuft occasionally reaches the threshold for local Na+ spike, resulting in stronger Ca2+ influx. During a burst of three somatic APs, the peak of dendritic Ca2+ in the apical tuft occurs with a delay of 20-50 ms depending on AP frequency.
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Affiliation(s)
- Shaina M Short
- Department of Neuroscience, UConn Health, Farmington, Connecticut
| | | | - Wen-Liang Zhou
- Department of Neuroscience, UConn Health, Farmington, Connecticut
| | - Corey D Acker
- Center for Cell Analysis and Modeling, UConn Health, Farmington, Connecticut
| | - Marko A Popovic
- Department of Cellular and Molecular Physiology, Yale University, New Haven, Connecticut
| | - Dejan Zecevic
- Department of Cellular and Molecular Physiology, Yale University, New Haven, Connecticut
| | - Srdjan D Antic
- Department of Neuroscience, UConn Health, Farmington, Connecticut; .,Stem Cell Institute, UConn Health, Farmington, Connecticut; and.,Institute for Systems Genomics, UConn Health, Farmington, Connecticut
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9
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Kastellakis G, Cai DJ, Mednick SC, Silva AJ, Poirazi P. Synaptic clustering within dendrites: an emerging theory of memory formation. Prog Neurobiol 2015; 126:19-35. [PMID: 25576663 PMCID: PMC4361279 DOI: 10.1016/j.pneurobio.2014.12.002] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 12/29/2014] [Accepted: 12/29/2014] [Indexed: 11/30/2022]
Abstract
It is generally accepted that complex memories are stored in distributed representations throughout the brain, however the mechanisms underlying these representations are not understood. Here, we review recent findings regarding the subcellular mechanisms implicated in memory formation, which provide evidence for a dendrite-centered theory of memory. Plasticity-related phenomena which affect synaptic properties, such as synaptic tagging and capture, synaptic clustering, branch strength potentiation and spinogenesis provide the foundation for a model of memory storage that relies heavily on processes operating at the dendrite level. The emerging picture suggests that clusters of functionally related synapses may serve as key computational and memory storage units in the brain. We discuss both experimental evidence and theoretical models that support this hypothesis and explore its advantages for neuronal function.
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Affiliation(s)
- George Kastellakis
- Institute of Molecular Biology and Biotechnology (IMBB), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1385, GR 70013 Heraklion, Greece
| | - Denise J Cai
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, UCLA, 2554 Gonda Center, Los Angeles, CA 90095, United States
| | - Sara C Mednick
- Department of Psychology, University of California, 900 University Avenue, Riverside, CA 92521, United States
| | - Alcino J Silva
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, UCLA, 2554 Gonda Center, Los Angeles, CA 90095, United States
| | - Panayiota Poirazi
- Institute of Molecular Biology and Biotechnology (IMBB), Foundation for Research and Technology, Hellas (FORTH), P.O. Box 1385, GR 70013 Heraklion, Greece.
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