scholarly journals BACE1 Is Necessary for Experience-Dependent Homeostatic Synaptic Plasticity in Visual Cortex

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Emily Petrus ◽  
Hey-Kyoung Lee
Keyword(s):  
Synaptic Plasticity ◽  
Visual Cortex ◽  
Synaptic Transmission ◽  
Sensory Experience ◽  
Synaptic Function ◽  
Excitatory Synaptic Transmission ◽  
Early Gene ◽  
Dependent Manner ◽  
Homeostatic Synaptic Plasticity ◽  
Activity Dependent

Alzheimer’s disease (AD) is the most common form of age-related dementia, which is thought to result from overproduction and/or reduced clearance of amyloid-beta (Aβ) peptides. Studies over the past few decades suggest that Aβis produced in an activity-dependent manner and has physiological relevance to normal brain functions. Similarly, physiological functions forβ- andγ-secretases, the two key enzymes that produce Aβby sequentially processing the amyloid precursor protein (APP), have been discovered over recent years. In particular, activity-dependent production of Aβhas been suggested to play a role in homeostatic regulation of excitatory synaptic function. There is accumulating evidence that activity-dependent immediate early gene Arc is an activity “sensor,” which acts upstream of Aβproduction and triggers AMPA receptor endocytosis to homeostatically downregulate the strength of excitatory synaptic transmission. We previously reported that Arc is critical for sensory experience-dependent homeostatic reduction of excitatory synaptic transmission in the superficial layers of visual cortex. Here we demonstrate that mice lacking the major neuronalβ-secretase, BACE1, exhibit a similar phenotype: stronger basal excitatory synaptic transmission and failure to adapt to changes in visual experience. Our results indicate that BACE1 plays an essential role in sensory experience-dependent homeostatic synaptic plasticity in the neocortex.

scholarly journals Locally coordinated synaptic plasticity of visual cortex neurons in vivo

Science ◽  
2018 ◽  
Vol 360 (6395) ◽  
pp. 1349-1354 ◽  
Author(s):  
Sami El-Boustani ◽  
Jacque P. K. Ip ◽  
Vincent Breton-Provencher ◽  
Graham W. Knott ◽  
Hiroyuki Okuno ◽  
...  
Keyword(s):  
Synaptic Plasticity ◽  
Visual Cortex ◽  
Spike Timing ◽  
Early Gene ◽  
Functional Changes ◽  
Cortical Responses ◽  
Targeted Expression ◽  
Visual Cortex Neurons ◽  
Activity Dependent

Plasticity of cortical responses in vivo involves activity-dependent changes at synapses, but the manner in which different forms of synaptic plasticity act together to create functional changes in neurons remains unknown. We found that spike timing–induced receptive field plasticity of visual cortex neurons in mice is anchored by increases in the synaptic strength of identified spines. This is accompanied by a decrease in the strength of adjacent spines on a slower time scale. The locally coordinated potentiation and depression of spines involves prominent AMPA receptor redistribution via targeted expression of the immediate early gene product Arc. Hebbian strengthening of activated synapses and heterosynaptic weakening of adjacent synapses thus cooperatively orchestrate cell-wide plasticity of functional neuronal responses.

scholarly journals A common human brain-derived neurotrophic factor polymorphism leads to sustained depression of excitatory synaptic transmission by isoflurane in hippocampus

2022 ◽  
Author(s):  
Riley A. Williams ◽  
Kenneth W. Johnson ◽  
Francis S. Lee ◽  
Hugh C. Hemmings ◽  
Jimcy Platholi
Keyword(s):  
Synaptic Plasticity ◽  
Synaptic Transmission ◽  
Synaptic Vesicle ◽  
Neurotrophic Factor ◽  
Brain Derived Neurotrophic Factor ◽  
Synaptic Function ◽  
Excitatory Synaptic Transmission ◽  
Neurological Dysfunction ◽  
Synaptic Vesicle Exocytosis ◽  
Vesicle Exocytosis

Multiple presynaptic and postsynaptic targets have been identified for the reversible neurophysiological effects of general anesthetics on synaptic transmission and neuronal excitability. However, the synaptic mechanisms involved in persistent depression of synaptic transmission resulting in more prolonged neurological dysfunction following anesthesia are less clear. Here, we show that brain-derived neurotrophic factor (BDNF), a growth factor implicated in synaptic plasticity and dysfunction, enhances glutamate synaptic vesicle exocytosis, and that attenuation of vesicular BDNF release by isoflurane contributes to transient depression of excitatory synaptic transmission in mice. This reduction in synaptic vesicle exocytosis was irreversible in neurons that release less endogenous BDNF due to a polymorphism (BDNF Val66Met) compared to wild-type mouse hippocampal neurons following isoflurane exposure. These effects were prevented by exogenous application of BDNF. Our findings identify a role for a common human BDNF single nucleotide polymorphism (Val66Met; rs6265) in persistent changes of synaptic function following isoflurane exposure. These persistent alterations in excitatory synaptic transmission have important implications for the role of genotype in anesthetic effects on synaptic plasticity and neurocognitive function.

Reduced presynaptic efficiency of excitatory synaptic transmission impairs LTP in the visual cortex of BDNF-heterozygous mice

2006 ◽  
Vol 24 (12) ◽  
pp. 3519-3531 ◽  
Author(s):  
Ismail Abidin ◽  
Torben Köhler ◽  
Elke Weiler ◽  
Georg Zoidl ◽  
Ulf T. Eysel ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Synaptic Transmission ◽  
Excitatory Synaptic Transmission

scholarly journals MPTP modulates hippocampal synaptic transmission and activity-dependent synaptic plasticity via dopamine receptors

2012 ◽  
Vol 122 (3) ◽  
pp. 582-593 ◽  
Author(s):  
GuoQi Zhu ◽  
YuYing Huang ◽  
Ying Chen ◽  
YingHan Zhuang ◽  
Thomas Behnisch
Keyword(s):  
Synaptic Plasticity ◽  
Synaptic Transmission ◽  
Dopamine Receptors ◽  
Activity Dependent

scholarly journals Insulin Modulates Excitatory Synaptic Transmission and Synaptic Plasticity in the Mouse Hippocampus

Neuroscience ◽  
2019 ◽  
Vol 411 ◽  
pp. 237-254 ◽  
Author(s):  
Fangli Zhao ◽  
Jason J. Siu ◽  
Wei Huang ◽  
Candice Askwith ◽  
Lei Cao
Keyword(s):  
Synaptic Plasticity ◽  
Synaptic Transmission ◽  
Excitatory Synaptic Transmission ◽  
Mouse Hippocampus

scholarly journals Synaptic control of DNA methylation involves activity-dependent degradation of DNMT3A1 in the nucleus

2020 ◽  
Vol 45 (12) ◽  
pp. 2120-2130 ◽  
Author(s):  
Gonca Bayraktar ◽  
PingAn Yuanxiang ◽  
Alessandro D. Confettura ◽  
Guilherme M. Gomes ◽  
Syed A. Raza ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Synaptic Plasticity ◽  
Promoter Methylation ◽  
Dna Methyltransferase ◽  
De Novo ◽  
Memory Formation ◽  
Epigenetic Mark ◽  
Dependent Manner ◽  
Synaptic Control ◽  
Activity Dependent

Abstract DNA methylation is a crucial epigenetic mark for activity-dependent gene expression in neurons. Very little is known about how synaptic signals impact promoter methylation in neuronal nuclei. In this study we show that protein levels of the principal de novo DNA-methyltransferase in neurons, DNMT3A1, are tightly controlled by activation of N-methyl-D-aspartate receptors (NMDAR) containing the GluN2A subunit. Interestingly, synaptic NMDARs drive degradation of the methyltransferase in a neddylation-dependent manner. Inhibition of neddylation, the conjugation of the small ubiquitin-like protein NEDD8 to lysine residues, interrupts degradation of DNMT3A1. This results in deficits in promoter methylation of activity-dependent genes, as well as synaptic plasticity and memory formation. In turn, the underlying molecular pathway is triggered by the induction of synaptic plasticity and in response to object location learning. Collectively, the data show that plasticity-relevant signals from GluN2A-containing NMDARs control activity-dependent DNA-methylation involved in memory formation.

Sevoflurane Blocks Cholinergic Synaptic Transmission Postsynaptically but Does Not Affect Short-term Potentiation

2005 ◽  
Vol 102 (5) ◽  
pp. 920-928 ◽  
Author(s):  
Hiroaki Naruo ◽  
Shin Onizuka ◽  
David Prince ◽  
Mayumi Takasaki ◽  
Naweed I. Syed
Keyword(s):  
Synaptic Plasticity ◽  
Synaptic Transmission ◽  
Fluorescent Imaging ◽  
Posttetanic Potentiation ◽  
Dependent Manner ◽  
General Anesthetics ◽  
Short Term ◽  
Concentration Dependent Manner ◽  
Cholinergic Synaptic Transmission ◽  
Term Potentiation

Background As compared with their effects on both inhibitory and excitatory synapses, little is known about the mechanisms by which general anesthetics affect synaptic plasticity that forms the basis for learning and memory at the cellular level. To test whether clinically relevant concentrations of sevoflurane affect short-term potentiation involving cholinergic synaptic transmission, the soma-soma synapses between identified, postsynaptic neurons were used. Methods Uniquely identifiable neurons visceral dorsal 4 (presynaptic) and left pedal dorsal 1 (postsynaptic) of the mollusk Lymnaea stagnalis were isolated from the intact ganglion and paired overnight in a soma-soma configuration. Simultaneous intracellular recordings coupled with fluorescent imaging of the FM1-43 dye were made in either the absence or the presence of sevoflurane. Results Cholinergic synapses, similar to those observed in vivo, developed between the neurons, and the synaptic transmission exhibited classic short-term, posttetanic potentiation. Action potential-induced (visceral dorsal 4), 1:1 excitatory postsynaptic potentials were reversibly and significantly suppressed by sevoflurane in a concentration-dependent manner. Fluorescent imaging with the dye FM1-43 revealed that sevoflurane did not affect presynaptic exocytosis or endocytosis; instead, postsynaptic nicotinic acetylcholine receptors were blocked in a concentration-dependent manner. To test the hypothesis that sevoflurane affects short-term potentiation, a posttetanic potentiation paradigm was used, and synaptic transmission was examined in either the presence or the absence of sevoflurane. Although 1.5% sevoflurane significantly reduced synaptic transmission between the paired cells, it did not affect the formation or retention of posttetanic potentiation at this synapse. Conclusions This study demonstrates that sevoflurane blocks cholinergic synaptic transmission postsynaptically but does not affect short-term synaptic plasticity at the visceral dorsal 4-left pedal dorsal 1 synapse.

Sign in / Sign up

Export Citation Format

Share Document