Topics

SNAP-25 phosphorylation at Ser187 is not involved in Ca or phorbolester-dependent potentiation of synaptic release.

07:00 EST 30th November 2019 | BioPortfolio

Summary of "SNAP-25 phosphorylation at Ser187 is not involved in Ca or phorbolester-dependent potentiation of synaptic release."

SNAP-25, one of the three SNARE-proteins responsible for synaptic release, can be phosphorylated by Protein Kinase C on Ser-187, close to the fusion pore. In neuroendocrine cells, this phosphorylation event potentiates vesicle recruitment into releasable pools, whereas the consequences of phosphorylation for synaptic release remain unclear. We mutated Ser-187 and expressed two mutants (S187C and S187E) in the context of the SNAP-25B-isoform in SNAP-25 knockout glutamatergic autaptic neurons. Whole-cell patch clamp recordings were performed to assess the effect of Ser-187 phosphorylation on synaptic transmission. Blocking phosphorylation by expressing the S187C mutant did not affect synapse density, basic evoked or spontaneous neurotransmission, the readily-releasable pool size or its Ca-independent or Ca-dependent replenishment. Furthermore, it did not affect the response to phorbol esters, which activate PKC. Expressing S187C in the context of the SNAP-25A isoform also did not affect synaptic transmission. Strikingly, the - potentially phosphomimetic - mutant S187E reduced spontaneous release and release probability, with the largest effect seen in the SNAP-25B isoform, showing that a negative charge in this position is detrimental for neurotransmission, in agreement with electrostatic fusion triggering. During the course of our experiments, we found that higher SNAP-25B expression levels led to decreased paired pulse potentiation, probably due to higher release probabilities. Under these conditions, the potentiation of evoked EPSCs by phorbol esters was followed by a persistent down-regulation, probably due to a ceiling effect. In conclusion, our results indicate that phosphorylation of Ser-187 in SNAP-25 is not involved in modulation of synaptic release by Ca or phorbol esters.

Affiliation

Journal Details

This article was published in the following journal.

Name: Molecular and cellular neurosciences
ISSN: 1095-9327
Pages: 103452

Links

DeepDyve research library

PubMed Articles [11464 Associated PubMed Articles listed on BioPortfolio]

Role of microtubules in late-associative plasticity of hippocampal Schaffer collateral-CA1 synapses in mice.

The microtubule network represents a key scaffolding structure that forms part of the neuronal cytoskeleton and contributes to biomolecule exchange within neurons. However, researchers have not determ...

Synaptic dopamine release is positively regulated by SNAP-25 that involves in benzoapyrene-induced neurotoxicity.

Benzo[a]pyrene (B[a]P) is a ubiquitous neurotoxic pollutant that widely distributes in the natural environment. However, the exact mechanism of B[a]P-induced neurotoxicity has not been well establishe...

Epigenetic regulation of microglial phosphatidylinositol 3-kinase pathway involved in long-term potentiation and synaptic plasticity in rats.

Microglia are the main form of immune defense in the central nervous system. Microglia express phosphatidylinositol 3-kinase (PI3K), which has been shown to play a significant role in synaptic plastic...

Long-term ketamine administration causes Tau protein phosphorylation and Tau protein-dependent AMPA receptor reduction in the hippocampus of mice.

As a recreational drug of abuse and an injectable anesthetic, ketamine has been shown to cause cognitive dysfunction and induce psychotic states. Although the specific mechanism is still unclear, it m...

Neuromodulator Signaling Bidirectionally Controls Vesicle Numbers in Human Synapses.

Neuromodulators bind to pre- and postsynaptic G protein-coupled receptors (GPCRs), are able to quickly change intracellular cyclic AMP (cAMP) and Ca levels, and are thought to play important roles in ...

Clinical Trials [3190 Associated Clinical Trials listed on BioPortfolio]

Synaptic Injury and Functional Connectivity in Alzheimer's Disease

The purpose of this study is to examine cross-sectional associations between CSF markers of synaptic injury (Ng and SNAP-25) and functional connectivity in default and semantic memory netw...

A Study to Assess Indeics of SNAP vs VISTA on Surgical Patients Undergoing General Anesthesia

Establish the range of index values for the SNAP II corresponding to each anesthetic state studied.

The Indiana SNAP-Ed Long-term Study Sequel

The goal of the study is to determine the immediate and long-term effects of SNAP-Ed on the dietary intake of participants.

Feasibility Study of a Novel Device for Chronic Wounds

The purpose of this study is to evaluate the feasibility and usability of a new portable and compact wound dressing device for the treatment of small chronic skin wounds.

Clinical Evaluation of the SNaP Wound Care System

The purpose of this study is to assess the efficacy of design improvements of the Spiracur SNaP Wound Care System. This study prospectively evaluates the safety and efficacy of current and...

Medical and Biotech [MESH] Definitions

A family of synaptic vesicle-associated proteins involved in the short-term regulation of NEUROTRANSMITTER release. Synapsin I, the predominant member of this family, links SYNAPTIC VESICLES to ACTIN FILAMENTS in the presynaptic nerve terminal. These interactions are modulated by the reversible PHOSPHORYLATION of synapsin I through various signal transduction pathways. The protein is also a substrate for cAMP- and CALCIUM-CALMODULIN-DEPENDENT PROTEIN KINASES. It is believed that these functional properties are also shared by synapsin II.

A persistent increase in synaptic efficacy, usually induced by appropriate activation of the same synapses. The phenomenological properties of long-term potentiation suggest that it may be a cellular mechanism of learning and memory.

A synaptic membrane protein involved in MEMBRANE FUSION of SYNAPTIC VESICLES with the presynaptic membranes. It is the prototype member of the R-SNARE PROTEINS.

A persistent activity-dependent decrease in synaptic efficacy between NEURONS. It typically occurs following repeated low-frequency afferent stimulation, but it can be induced by other methods. Long-term depression appears to play a role in MEMORY.

A group of enzymes that are dependent on CYCLIC AMP and catalyze the phosphorylation of SERINE or THREONINE residues on proteins. Included under this category are two cyclic-AMP-dependent protein kinase subtypes, each of which is defined by its subunit composition.

Quick Search


DeepDyve research library

Relevant Topic

Collaborations in biotechnology
Commercial and academic collaborations are used throughout the biotechnology and pharmaceutical sector to enhance research and product development. Collaborations can take the form of research and evaluation agreements, licensing, partnerships etc. ...


Searches Linking to this Article