scholarly journals Competition for synaptic building blocks shapes synaptic plasticity

2017 ◽  
Author(s):  
Jochen Triesch ◽  
Anh Duong Vo ◽  
Anne-Sophie Hafner
Keyword(s):  
Mathematical Model ◽  
Synaptic Plasticity ◽  
Learning And Memory ◽  
Time Scales ◽  
Building Blocks ◽  
Neurotransmitter Receptors ◽  
Rapid Exchange ◽  
Heterosynaptic Plasticity ◽  
Spontaneous Fluctuations ◽  
Receptor Pool

AbstractChanges in the efficacies of synapses are thought to be the neurobiological basis of learning and memory. The efficacy of a synapse depends on its current number of neurotransmitter receptors. Recent experiments have shown that these receptors are highly dynamic, moving back and forth between synapses on time scales of seconds and minutes. This suggests spontaneous fluctuations in synaptic efficacies and a competition of nearby synapses for available receptors. Here we propose a mathematical model of this competition of synapses for neurotransmitter receptors from a local dendritic pool. Using minimal assumptions, the model produces a fast multiplicative scaling behavior of synapses. Furthermore, the model explains a transient form of heterosynaptic plasticity and predicts that its amount is inversely related to the size of the local receptor pool. Overall, our model reveals logistical tradeoffs during the induction of synaptic plasticity due to the rapid exchange of neurotransmitter receptors between synapses.

scholarly journals Competition for synaptic building blocks shapes synaptic plasticity

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Jochen Triesch ◽  
Anh Duong Vo ◽  
Anne-Sophie Hafner
Keyword(s):  
Mathematical Model ◽  
Synaptic Plasticity ◽  
Learning And Memory ◽  
Time Scales ◽  
Building Blocks ◽  
Neurotransmitter Receptors ◽  
Rapid Exchange ◽  
Heterosynaptic Plasticity ◽  
Spontaneous Fluctuations ◽  
Receptor Pool

Changes in the efficacies of synapses are thought to be the neurobiological basis of learning and memory. The efficacy of a synapse depends on its current number of neurotransmitter receptors. Recent experiments have shown that these receptors are highly dynamic, moving back and forth between synapses on time scales of seconds and minutes. This suggests spontaneous fluctuations in synaptic efficacies and a competition of nearby synapses for available receptors. Here we propose a mathematical model of this competition of synapses for neurotransmitter receptors from a local dendritic pool. Using minimal assumptions, the model produces a fast multiplicative scaling behavior of synapses. Furthermore, the model explains a transient form of heterosynaptic plasticity and predicts that its amount is inversely related to the size of the local receptor pool. Overall, our model reveals logistical tradeoffs during the induction of synaptic plasticity due to the rapid exchange of neurotransmitter receptors between synapses.

The Neuromolecular Brain

Neuro ◽  
2013 ◽  
Author(s):  
Nikolas Rose ◽  
Joelle M. Abi-Rached
Keyword(s):  
Gene Expression ◽  
Synaptic Plasticity ◽  
Learning And Memory ◽  
Time Scales ◽  
Molecular Level ◽  
Human Life ◽  
Neuronal Circuits ◽  
Molecular Processes ◽  
Nerve Development ◽  
The Brain

This chapter examines the neuromolecular and plastic brain. Ideas about plasticity and the openness of brains to environment influences, from initial evidence about nerve development, through the recognition that synaptic plasticity was the very basis of learning and memory, to evidence about the influence of environment on gene expression and the persistence throughout life of the capacity to make new neurons—all this made the neuromolecular brain seem exquisitely open to its milieu, with changes at the molecular level occurring throughout the course of a human life and thus shaping the growth, organization, and regeneration of neurons and neuronal circuits at time scales from the millisecond to the decade. This was an opportunity to explore the myriad ways in which the milieu got “under the skin,” implying an openness of these molecular processes of the brain to biography, sociality, and culture, and hence perhaps even to history and politics.

scholarly journals Behavioral Time Scale Plasticity of Place Fields: Mathematical Analysis

2020 ◽  
Author(s):  
Harel Z. Shouval ◽  
Ian Cone
Keyword(s):  
Mathematical Model ◽  
Synaptic Plasticity ◽  
Fixed Points ◽  
Time Scales ◽  
Simple Mathematical Model ◽  
System Parameters ◽  
Temporal Correlations ◽  
Postsynaptic Activity ◽  
Naturally Occurring ◽  
Place Fields

AbstractTraditional synaptic plasticity experiments and models depend on tight temporal correlations between pre- and postsynaptic activity. These tight temporal correlations, on the order of tens of milliseconds, are incompatible with significantly longer behavioral time scales, and as such might not be able to account for plasticity induced by behavior. Indeed, recent findings in hippocampus suggest that rapid, bidirectional synaptic plasticity which modifies place fields in CA1 operates at behavioral time scales. These experimental results suggest that presynaptic activity generates synaptic eligibility traces both for potentiation and depression, which last on the order of seconds. These traces can be converted to changes in synaptic efficacies by the activation of an instructive signal that depends on naturally occurring or experimentally induced plateau potentials. We have developed a simple mathematical model that is consistent with these observations. This model can be fully analyzed to find the fixed points of induced place fields, the convergence to these fixed points, and how these fixed points depend on system parameters such as the size and shape of presynaptic place fields, the animal’s velocity, and the parameters of the plasticity rule.

The Effects of P75NTR on Learning Memory Mediated by Hippocampal Apoptosis and Synaptic Plasticity

2020 ◽  
Vol 26 ◽  
Author(s):  
Jun-Jie Tang ◽  
Shuang Feng ◽  
Xing-Dong Chen ◽  
Hua Huang ◽  
Min Mao ◽  
...  
Keyword(s):  
Synaptic Plasticity ◽  
Learning And Memory ◽  
Neurological Diseases ◽  
Neurotrophin Receptor ◽  
P75 Neurotrophin Receptor ◽  
Negative Effects ◽  
Apoptotic Effect ◽  
New Ideas ◽  
The Relationship

: Neurological diseases bring great mental and physical torture to the patients, and have long-term and sustained negative effects on families and society. The attention to neurological diseases is increasing, and the improvement of the material level is accompanied by an increase in the demand for mental level. The p75 neurotrophin receptor (p75NTR) is a low-affinity neurotrophin receptor and involved in diverse and pleiotropic effects in the developmental and adult central nervous system (CNS). Since neurological diseases are usually accompanied by the regression of memory, the pathogenesis of p75NTR also activates and inhibits other signaling pathways, which has a serious impact on the learning and memory of patients. The results of studies shown that p75NTR is associated with LTP/LTD-induced synaptic enhancement and inhibition, suggest that p75NTR may be involved in the progression of synaptic plasticity. And its pro-apoptotic effect is associated with activation of proBDNF and inhibition of proNGF, and TrkA/p75NTR imbalance leads to pro-survival or pro-apoptotic phenomena. It can be inferred that p75NTR mediates apoptosis in the hippocampus and amygdale, which may affect learning and memory behavior. This article mainly discusses the relationship between p75NTR and learning memory and associated mechanisms, which may provide some new ideas for the treatment of neurological diseases.

Synapsin Regulates Basal Synaptic Strength, Synaptic Depression, and Serotonin-Induced Facilitation of Sensorimotor Synapses in Aplysia

2007 ◽  
Vol 98 (6) ◽  
pp. 3568-3580 ◽  
Author(s):  
Diasinou Fioravante ◽  
Rong-Yu Liu ◽  
Anne K. Netek ◽  
Leonard J. Cleary ◽  
John H. Byrne
Keyword(s):  
Synaptic Plasticity ◽  
Synaptic Vesicle ◽  
Transmitter Release ◽  
Computational Analysis ◽  
Spontaneous Recovery ◽  
Synaptic Strength ◽  
Short Term ◽  
Homosynaptic Depression ◽  
Heterosynaptic Plasticity

Synapsin is a synaptic vesicle-associated protein implicated in the regulation of vesicle trafficking and transmitter release, but its role in heterosynaptic plasticity remains elusive. Moreover, contradictory results have obscured the contribution of synapsin to homosynaptic plasticity. We previously reported that the neuromodulator serotonin (5-HT) led to the phosphorylation and redistribution of Aplysia synapsin, suggesting that synapsin may be a good candidate for the regulation of vesicle mobilization underlying the short-term synaptic plasticity induced by 5-HT. This study examined the role of synapsin in homosynaptic and heterosynaptic plasticity. Overexpression of synapsin reduced basal transmission and enhanced homosynaptic depression. Although synapsin did not affect spontaneous recovery from depression, it potentiated 5-HT–induced dedepression. Computational analysis showed that the effects of synapsin on plasticity could be adequately simulated by altering the rate of Ca2+-dependent vesicle mobilization, supporting the involvement of synapsin not only in homosynaptic but also in heterosynaptic forms of plasticity by regulating vesicle mobilization.

scholarly journals The brain-tumor related protein podoplanin regulates synaptic plasticity and hippocampus-dependent learning and memory

2016 ◽  
Vol 48 (8) ◽  
pp. 652-668 ◽  
Author(s):  
Ana Cicvaric ◽  
Jiaye Yang ◽  
Sigurd Krieger ◽  
Deeba Khan ◽  
Eun-Jung Kim ◽  
...  
Keyword(s):  
Brain Tumor ◽  
Synaptic Plasticity ◽  
Learning And Memory ◽  
Related Protein ◽  
Dependent Learning ◽  
The Brain

Multiscale Convective Organization and the YOTC Virtual Global Field Campaign

2012 ◽  
Vol 93 (8) ◽  
pp. 1171-1187 ◽  
Author(s):  
Mitchell W. Moncrieff ◽  
Duane E. Waliser ◽  
Martin J. Miller ◽  
Melvyn A. Shapiro ◽  
Ghassem R. Asrar ◽  
...  
Keyword(s):  
Time Scales ◽  
Climate Models ◽  
Water Cycle ◽  
Building Blocks ◽  
Tropical Convection ◽  
Global Water Cycle ◽  
Weather And Climate ◽  
Impact Phenomena ◽  
Meteorological Systems ◽  
The Tropics

The Year of Tropical Convection (YOTC) project recognizes that major improvements are needed in how the tropics are represented in climate models. Tropical convection is organized into multiscale precipitation systems with an underlying chaotic order. These organized systems act as building blocks for meteorological events at the intersection of weather and climate (time scales up to seasonal). These events affect a large percentage of the world's population. Much of the uncertainty associated with weather and climate derives from incomplete understanding of how meteorological systems on the mesoscale (~1–100 km), synoptic scale (~1,000 km), and planetary scale (~10,000 km) interact with each other. This uncertainty complicates attempts to predict high-impact phenomena associated with the tropical atmosphere, such as tropical cyclones, the Madden–Julian oscillation, convectively coupled tropical waves, and the monsoons. These and other phenomena influence the extratropics by migrating out of the tropics and by the remote effects of planetary waves, including those generated by the MJO. The diurnal and seasonal cycles modulate all of the above. It will be impossible to accurately predict climate on regional scales or to comprehend the variability of the global water cycle in a warmer world without comprehensively addressing tropical convection and its interactions across space and time scales.

Sign in / Sign up

Export Citation Format

Share Document