Synaptic plasticity

  • Article
    | Open Access

    Non-human primate models of autism spectrum disorder (ASD) are few and not well characterised. Here, the authors describe synaptic function and gene expression changes in a marmoset model of ASD from birth to juvenile, highlighting its similarity to features observed in human ASD.

    • Satoshi Watanabe
    • , Tohru Kurotani
    •  & Noritaka Ichinohe
  • Article
    | Open Access

    Brain plasticity declines with age. Here, the authors show that NKCC1 regulates oligodendrocyte activity, facilitating neuronal plasticity during juvenile. Inducing activation of oligodendrocytic NKCC1 results in restoration of neuronal plasticity in the adult mouse brain.

    • Yoshihiko Yamazaki
    • , Yoshifumi Abe
    •  & Kenji F. Tanaka
  • Article
    | Open Access

    Glucocorticoids are associated with stress. Here, the authors show that high levels of glucocorticoid stress promote secretory autophagy of matrix metalloproteinase 9 via a stress responsive chaperone, increasing brain-derived neurotrophic factor processing and potentially altering adult synaptic plasticity.

    • Silvia Martinelli
    • , Elmira A. Anderzhanova
    •  & Nils C. Gassen
  • Article
    | Open Access

    Synaptic inputs on neuronal dendrites exhibit remarkable organization at different spatial scales, which emerges during the early postnatal development. Kirchner and Gjorgjieva propose a biophysically motivated computational model to explain the different types of organization in mouse and ferret.

    • Jan H. Kirchner
    •  & Julijana Gjorgjieva
  • Article
    | Open Access

    Post‐tetanic potentiation (PTP) is a major form of plasticity at hippocampal mossy fiber synapses and is considered an entirely presynaptic phenomenon. The authors show that mossy fiber PTP not only lacks associativity, but rather shows anti‐associative induction properties, implementing a brake on mossy fiber detonation.

    • David Vandael
    • , Yuji Okamoto
    •  & Peter Jonas
  • Article
    | Open Access

    Dopamine neurons in the mushroom body help Drosophila learn to approach rewards and avoid punishments. Here, the authors propose a model in which dopaminergic learning signals encode reinforcement prediction errors by utilising feedback reinforcement predictions from mushroom body output neurons.

    • James E. M. Bennett
    • , Andrew Philippides
    •  & Thomas Nowotny
  • Article
    | Open Access

    The physical distance between synaptic Ca2+ channels and sensors modulates short-term plasticity (STP). Here, the authors show that synaptic release factors Unc13A and Unc13B distinctly couple with Ca2+ channels and contribute to the neural decoding of distinct sensory information in Drosophila.

    • Atefeh Pooryasin
    • , Marta Maglione
    •  & Stephan J. Sigrist
  • Article
    | Open Access

    Optogenetic control of molecules is important in cell biology and neuroscience. Here, the authors describe an optogenetic tool to control the Ca²+/calmodulin-dependent protein kinase II and use it to control plasticity at the single synapse level.

    • Akihiro C. E. Shibata
    • , Hiromi H. Ueda
    •  & Hideji Murakoshi
  • Article
    | Open Access

    Stress-induced glucocorticoids cause mitochondrial damage in neurons, but they are not cleared by mitophagy. Here, the authors show that glucocorticoids inhibit NIX-dependent basal mitophagy, contributing to neurodegeneration in a mouse model that can be reversed by pretreatment with a NIX enhancer.

    • Gee Euhn Choi
    • , Hyun Jik Lee
    •  & Ho Jae Han
  • Article
    | Open Access

    Long-term potentiation at hippocampal CA1 synapses can be due to increasing the number and/or single-channel conductance of AMPA receptors. The authors show that PKA and CaMKII are necessary and together sufficient to increase single channel conductance, via insertion of calcium-permeable AMPA receptors.

    • Pojeong Park
    • , John Georgiou
    •  & Graham L. Collingridge
  • Article
    | Open Access

    The GABARAP protein is known to support the stability of GABAA receptors (GABAARs) in synapses, but the underlying molecular mechanisms remained to be elucidated. Here authors use biochemistry, X-ray crystallography and electrophsyiology and show that GABARAP directly binds to a previously unappreciated region in the γ2 subunit of GABAAR.

    • Jin Ye
    • , Guichang Zou
    •  & Chao Wang
  • Article
    | Open Access

    LTP and LTD are involved in shaping hippocampal place field representations. Here, the authors show that de novo pathway-specific hippocampal LTD changes dynamics and stability of newly formed place fields, regulating acquisition and maintenance of novel spatial information in adult rats.

    • Donovan M. Ashby
    • , Stan B. Floresco
    •  & Yu Tian Wang
  • Article
    | Open Access

    Endocannabinoid levels are controlled by the fine balance between their synthesis and degradation. Here, the authors show that memory formation through fear conditioning selectively accelerates the degradation of endocannabinoids in the cerebellum via a lasting increase in GABA release.

    • Christophe J. Dubois
    • , Jessica Fawcett-Patel
    •  & Siqiong June Liu
  • Article
    | Open Access

    Acute administration of EPA impairs learning and memory and hippocampal LTP in mice that was mediated through enhancing GABAergic transmission via the 5-HT6R. DHA can prevent EPA-induced impairments at a ratio of EPA to DHA similar to that in marine fish oil via the 5-HT2CR.

    • Ji-Hong Liu
    • , Qian Wang
    •  & Tian-Ming Gao
  • Article
    | Open Access

    Transport of membrane proteins within the cell is thought to mainly rely on microtubule-based transport, but the role of microtubules in neuronal cell recycling of synaptic vesicles is unclear. Here, the authors show that axonal movement of recycling vesicles may be driven not by microtubules but primarily by actin polymerization.

    • Nicolas Chenouard
    • , Feng Xuan
    •  & Richard W. Tsien
  • Article
    | Open Access

    Cell surface proteins contribute to neuronal development and activity-dependent synaptic plasticity. Here, the authors perform a time-resolved surfaceome analysis of developing primary neurons and in response to homeostatic synaptic scaling and chemical long-term potentiation (cLTP), revealing surface proteome remodeling largely independent of global proteostasis.

    • Marc van Oostrum
    • , Benjamin Campbell
    •  & Bernd Wollscheid
  • Article
    | Open Access

    Inhibitory interneuron subtypes differentially control place cell representations in CA1. Here, the authors show that parvalbumin and somatostatin interneuron synapses onto CA1 pyramidal neurons exhibit distinct plasticity mechanisms and incorporating this insight into circuit-level modeling leads to stable place cell representations.

    • Matt Udakis
    • , Victor Pedrosa
    •  & Jack R. Mellor
  • Article
    | Open Access

    Presynaptic spike timing-dependent long-term depression at hippocampal CA3-CA1 synapses is evident until the third postnatal week in mice. The authors show that maturation beyond four weeks is associated with a switch to long-term potentiation in which astrocytes play a central role.

    • Rafael Falcón-Moya
    • , Mikel Pérez-Rodríguez
    •  & Antonio Rodríguez-Moreno
  • Article
    | Open Access

    Stein, Barbosa et al. show that anti-NMDAR encephalitis and schizophrenia are characterized by reduced serial dependence in spatial working memory. Cortical network simulations show that this can be parsimoniously explained by a reduction in NMDAR-dependent short-term synaptic potentiation in these diseases.

    • Heike Stein
    • , Joao Barbosa
    •  & Albert Compte
  • Article
    | Open Access

    Inhibition in spinal nociceptive pathways is weaker and more labile in lamina I —where thermal input is primarily processed— than in lamina II that encodes predominantly high threshold mechanical input. This explains why noxious thermal input makes spinal circuits prone to catastrophic sensitization.

    • Francesco Ferrini
    • , Jimena Perez-Sanchez
    •  & Yves De Koninck
  • Article
    | Open Access

    Bellec et al. present a mathematically founded approximation for gradient descent training of recurrent neural networks without backwards propagation in time. This enables biologically plausible training of spike-based neural network models with working memory and supports on-chip training of neuromorphic hardware.

    • Guillaume Bellec
    • , Franz Scherr
    •  & Wolfgang Maass
  • Article
    | Open Access

    Fragile X Mental Retardation Protein regulates synaptic plasticity and its loss results in Fragile X Syndrome. Here, the authors show that the FMRP(1-297)-tat peptide can permeate the BBB, restore protein translation and mossy fiber LTP, and reduce elevated levels of activity in Fmr1 KO mice.

    • Xiaoqin Zhan
    • , Hadhimulya Asmara
    •  & Ray W. Turner
  • Article
    | Open Access

    Enduring changes in synaptic efficacy are highly sensitive to stress. Here, the authors show that astrocytic delivery of metabolites has an important role in the stress-mediated impairment of synaptic plasticity.

    • Ciaran Murphy-Royal
    • , April D. Johnston
    •  & Grant R. Gordon
  • Article
    | Open Access

    The formation of functional synaptic clusters (FSCs) and their impact on somatic membrane potential (sVm) in vivo are poorly understood. Here, the authors develop a computational approach to show that FSCs have to form via local rather than global plasticity and be moderately large to impact sVm.

    • Balázs B. Ujfalussy
    •  & Judit K. Makara
  • Article
    | Open Access

    Previous studies implicate the hippocampal–amygdala pathway in contextual fear conditioning, in which animals learn to associate a neutral context with an aversive stimulus and display fear responses to dangerous situations. Here the authors show that selective strengthening of hippocampal–amygdala pathway contributes to encoding adaptive fear memory for threat-predictive context.

    • Woong Bin Kim
    •  & Jun-Hyeong Cho
  • Article
    | Open Access

    The mechanisms underlying the maturation of learning and memory abilities are poorly understood. Here, authors show that episodic learning produces persistent neuronal activation, BDNF-dependent increase in excitatory synapse markers (synaptophysin and PSD-95), and significant maturation of AMPA receptor synaptic responses in the hippocampus of infant rats and mice compared to juveniles and adults.

    • Benjamin Bessières
    • , Alessio Travaglia
    •  & Cristina M. Alberini
  • Article
    | Open Access

    Sensory stimuli usually arrive simultaneously but the neural-circuit mechanisms that combine multiple streams of sensory information are incompletely understood. The authors here show that visual-auditory pairing drives plasticity in multi-modal neuron networks within the mouse visual cortex.

    • Thomas Knöpfel
    • , Yann Sweeney
    •  & Samuel J. Barnes
  • Article
    | Open Access

    There is growing evidence that autophagy might serve specialized functions in neurons besides its role in protein homeostasis. In this study, authors demonstrate that axonal retrograde transport of BDNF/TrkB in neuronal amphisomes is involved in plasticity-relevant local signaling at presynaptic boutons and that SIPA1L2, a member of the SIPA1L family of neuronal RapGAPs, associates via LC3b to TrkB-containing amphisomes to regulate its motility and signaling at the axon terminals

    • Maria Andres-Alonso
    • , Mohamed Raafet Ammar
    •  & Michael R. Kreutz
  • Article
    | Open Access

    The mechanisms regulating the turnover of the AMPARs in the synapse, which is critically important to sustain basic synaptic activity, remains unclear. In this study, authors used single-molecule imaging techniques to demonstrate that AMPAR tetramers are not stable entities and readily fall apart to dimers and monomers that could reform to tetramers at the synapse, and that rapidly diffusing monomers in the plasma membrane are primarily responsible for the AMPAR turnover in the synapse.

    • Jyoji Morise
    • , Kenichi G. N. Suzuki
    •  & Shogo Oka
  • Article
    | Open Access

    It’s well known that hippocampal synaptic plasticity and memory are impaired in experimental models of metabolic diseases, however, it is unclear if maternal diet or metabolic alterations around the gestational age may multigenerationally affect learning and memory. In this study, authors demonstrate that maternal high fat diet-dependent insulin resistance affects synaptic plasticity and memory of descendants until the third generation via reduced exon specific brain-derived neurotrophic factor expression in the hippocampus of descendants

    • Salvatore Fusco
    • , Matteo Spinelli
    •  & Claudio Grassi
  • Article
    | Open Access

    How are stable memories maintained in the brain despite significant ongoing fluctuations in synaptic strengths? Here, the authors show that a model consistent with fluctuations, homeostasis and biologically plausible learning rules, naturally leads to memories implemented as dynamic attractors.

    • Lee Susman
    • , Naama Brenner
    •  & Omri Barak
  • Article
    | Open Access

    Multiplexed imaging of synaptic proteins can provide useful information on the heterogeneity of synaptic architecture and plasticity. Here the authors use high affinity locked nucleic acid probes and low affinity DNA imaging probes to achieve multiplexed confocal and super-resolution imaging of synaptic and cytoskeletal proteins.

    • Syuan-Ming Guo
    • , Remi Veneziano
    •  & Mark Bathe
  • Article
    | Open Access

    Caspase-2 is constitutively expressed in neurons yet its physiological function is not known. Here, the authors report a role for Caspase-2 activity in synaptic plasticity via a reduction in dendritic spine density through cleavage of Rictor suggesting a mechanism to explain the impairments in cognitive flexibility observed in Caspase-2 knockout mice.

    • Zhi-Xiang Xu
    • , Ji-Wei Tan
    •  & Baoji Xu
  • Article
    | Open Access

    Asymmetric subcellular mRNA distribution is important for local translation of neuronal mRNAs. Here the authors employed MS2 live-cell imaging and showed that the reporter mRNA containing the 3’ UTR of Rgs4 shows an anterograde transport bias, dependent on neuronal activity and the protein Staufen2, and mediates sustained mRNA recruitment to synapses.

    • Karl E. Bauer
    • , Inmaculada Segura
    •  & Michael A. Kiebler
  • Article
    | Open Access

    The authors use a forward genetic screen to discover postsynaptic factors required for homeostatic synaptic plasticity at the Drosophila neuromuscular junction. They identify insomniac and the ubiquitin ligase Cul3, genes involved in sleep regulation, to be necessary for retrograde homeostatic signalling at this synapse.

    • Koto Kikuma
    • , Xiling Li
    •  & Dion Dickman
  • Article
    | Open Access

    How astrocytes influence neuronal plasticity remains unclear, as they are typically considered as modulators of core mechanisms driven by neuronal components. Here, authors show that Long-term depression (LTD) induction in the hippocampus triggers calcium signaling in the astrocyte and enhances SNARE-dependent astrocytic glutamate release, which is then responsible for the activation of postsynaptic NMDA receptors and synaptic depression.

    • Marta Navarrete
    • , María I. Cuartero
    •  & José A. Esteban
  • Article
    | Open Access

    Activation of Ca2+/calmodulin-dependent kinase II (CaMKII) in dendritic spines is a key step of long-term potentiation (LTP) induction, yet the exact biochemical steps of CaMKIIα activation in dendritic spines remained elusive. In this study, the authors developed a novel imaging approach to monitor CaM interactions CaMKIIα in cultured hippocampal neurons after uncaging of glutamate. This allowed the authors to model the kinetics of CaMKIIα activation in single dendritic spines.

    • Jui-Yun Chang
    • , Yoshihisa Nakahata
    •  & Ryohei Yasuda
  • Article
    | Open Access

    The red nucleus (RN) is a midbrain nucleus known to be involved in the fine control of limb movements, but its role in motor learning is unclear. Here, the authors identified a neuronal population within the red nucleus, co-expressing Vglut2, PV and C1Ql2, which undergoes training-dependent plasticity.

    • Giorgio Rizzi
    • , Mustafa Coban
    •  & Kelly R. Tan
  • Article
    | Open Access

    Lowered synaptic density is believed to occur in major depressive disorder and PTSD, possibly as an effect of stress. Here, the authors use positron emission tomography (PET) to measure levels of the synaptic marker SV2A and show that SV2A density is lower in those with more severe symptoms of depression.

    • Sophie E. Holmes
    • , Dustin Scheinost
    •  & Irina Esterlis