• Recently, miRNA exocytosis by vesicle fusion in response to stimulation was observed in chromaffin cells, which are neuroendocrine cells in the sympathetic nervous system ( 24 ). (frontiersin.org)
  • CAPS was originally identified as a factor which reconstitutes secretion in permeabilised neuroendocrine cells, and has since been recognised as important in regulated release of DCVs in C. elegans and large dense core vesicles (LDCVs) in neuroendocrine chromaffin cells, as well as in SV exocytosis in neurons. (uni-goettingen.de)
  • Although overexpression studies had also implicated Munc13s in LDCV release in chromaffin cells, in this cell type no LDCV release deficit had ever been demonstrated in their absence, and CAPSs proteins had been suggested to be the main regulators of LDCV exocytosis. (uni-goettingen.de)
  • Taken together, our findings show that ubMunc13-2 and Munc13-1 regulate LDCV exocytosis in chromaffin cells. (uni-goettingen.de)
  • Signal transmission in neurons is accomplished by neurotransmitter release from the lumen of synaptic vesicles into the synaptic cleft of synapses where they are received by postsynaptic receptors 1 . (nature.com)
  • When signals are transmitted by synapses, messenger molecules (neurotransmitters) are released from storage chambers (synaptic vesicles) into the synaptic cleft, where they are "recognized" by neighboring nerve cells. (news-medical.net)
  • Membrane fusion generates an opening through which the molecules are expelled into the synaptic cleft via exocytosis. (msdmanuals.com)
  • It mediates fusion of synaptic vesicles with the presynaptic plasma membrane resulting in exocytosis of neurotransmitters. (nature.com)
  • To achieve this, the neuronal SNARE (i.e., soluble N -ethylmaleimide-sensitive factor attachment protein receptor) complex brings the vesicle and presynaptic membranes in close proximity, thereby, mediating the fusion of the two membranes resulting in exocytosis of neurotransmitters. (nature.com)
  • In the following decades, recycling routes for synaptic vesicle and for neurotransmitters were worked out, but only since the mid-1980s are the molecular mechanisms governing the steps in synaptic vesicle cycling becoming known. (sfn.org)
  • Communication among neuron and glial cells is mediated by various neurotransmitters being released from the vesicles through exocytosis. (neurosciencenews.com)
  • Neurons can release small molecule neurotransmitters very rapidly in part because synaptic vesicles are docked to the membrane at active zones. (rupress.org)
  • Pinocytosis is one type of endocytosis, the general process by which cells engulf external substances, gathering them into special membrane-bound vesicles contained within the cell . (britannica.com)
  • Neurotransmission relies on repeated cycles of exo- and endocytosis of the synaptic vesicles (SVs), in which several palmitoylated proteins play critical roles. (jci.org)
  • More than 90% of extracellular miRNAs are vesicle-free, but form a complex with proteins such as Agonaute2 (AGO2) ( 22 , 23 ). (frontiersin.org)
  • Thus, at least in mammals, both Munc13s and CAPS proteins are critical in the regulation of both SV and LDCV exocytosis in neurons as well as in neuroendocrine cells. (uni-goettingen.de)
  • SNAP-25 assembles with synaptobrevin and syntaxin-1, and the selective binding of these proteins enables vesicle docking and fusion to occur at active zones on the plasma membrane. (wikipedia.org)
  • Membrane-enclosed structures called vesicles transport proteins and lipids across the cell. (jove.com)
  • The distribution of proteins between the ER and Golgi complex is dynamic and is maintained by different coated vesicles. (jove.com)
  • Coat proteins can help sort the cargo and assemble on the donor membrane to initiate vesicle formation. (jove.com)
  • The COPI and COPII coat proteins share similar structural features with Clathrin but differ in cargo sorting and vesicle formation mechanisms. (jove.com)
  • Igarashi, M & Watanabe, M 2007, ' Roles of calmodulin and calmodulin-binding proteins in synaptic vesicle recycling during regulated exocytosis at submicromolar Ca 2+ concentrations ', Neuroscience Research , vol. 58, no. 3, pp. 226-233. (elsevierpure.com)
  • The development of STED microscopy has allowed researchers at the Max-Planck Institute for Biophysical Chemistry to image, for the first time, proteins from single synaptic vesicles, answering long-standing questions of neurocommunication (Nature, 13th April 2006). (mpg.de)
  • Other previous techniques that target vesicle fusion proteins damage them permanently and disable the target neuron for up to 24 hours, which is not appropriate for many behavioral experiments with short time constraints. (neurosciencenews.com)
  • These proteins facilitate membrane fusion, which is required for neurotransmitter exocytosis, recycling of the fused SV membrane components, and regeneration of fresh vesicles. (jci.org)
  • Using postmortem brain tissues from an INCL patient and tissue from the PPT1-knockout (PPT1-KO) mice that mimic INCL, we report here that PPT1 deficiency caused persistent membrane anchorage of the palmitoylated SV proteins, which hindered the recycling of the vesicle components that normally fuse with the presynaptic plasma membrane during SV exocytosis. (jci.org)
  • CAPS function in dense core vesicle docking parallels UNC-13 in synaptic vesicle docking, which suggests that these related proteins act similarly to promote docking of independent vesicle populations. (rupress.org)
  • Here, we describe a mechanism for dense core vesicle docking in neurons. (rupress.org)
  • We have found that the calcium-activated protein for secretion (CAPS) protein is required for dense core vesicle docking but not synaptic vesicle docking. (rupress.org)
  • In contrast, we see that UNC-13, a docking factor for synaptic vesicles, is not essential for dense core vesicle docking. (rupress.org)
  • Overexpression of open syntaxin can bypass the requirement for CAPS in dense core vesicle docking. (rupress.org)
  • How do neurons differentially regulate synaptic vesicle and dense core vesicle release? (rupress.org)
  • We tested the hypothesis that isoflurane inhibits exocytosis in dopaminergic neurons. (eneuro.org)
  • We used electrical stimulation or depolarization by elevated extracellular KCl to evoke exocytosis measured by quantitative live-cell fluorescence imaging in cultured rat ventral tegmental area neurons. (eneuro.org)
  • Thus, isoflurane inhibits exocytosis from dopaminergic neurons by a mechanism distinct from that in non-dopaminergic neurons involving reduced Ca 2+ entry through Ca V 2.1 and/or Ca V 2.2. (eneuro.org)
  • Here, we show that in dopaminergic neurons of the ventral tegmental area isoflurane acts via a sodium channel-independent mechanism to inhibit synaptic vesicle exocytosis in proportion to reduced presynaptic Ca 2+ flux mediated by Ca V 2.1 and/or Ca V 2.2, in contrast to its effects in non-dopaminergic neurons. (eneuro.org)
  • Following a fusion event, neurons must replenish their vesicle stocks to ensure that they are ready for the arrival of the next action potential. (elifesciences.org)
  • By comparison, vesicles that were inactivated using Opto-vTrap decluster in about 15 minutes, and the neurons regain their full functions within an hour. (neurosciencenews.com)
  • In Caenorhabditis elegans motor neurons, dense core vesicles dock at the plasma membrane but are excluded from active zones at synapses. (rupress.org)
  • In this review, we discuss recent findings on how CaM regulates synaptic vesicle recycling by controlling the SNARE mechanism, which is the molecular machinery that mediates exocytosis. (elsevierpure.com)
  • this observation demonstrates that vesicle-free miRNAs are secreted from neuroendocrine cells, in a manner similar to hormone secretion. (frontiersin.org)
  • Adipocyte-derived extracellular vesicles increase insulin secretion through transport of insulinotropic protein cargo. (mpg.de)
  • Comparable reductions in exocytosis and Ca 2+ influx were produced by lowering extracellular [Ca 2+ ]. (eneuro.org)
  • It is believed that a vesicle may carry extracellular fluid to the opposite side of the cell, where it undergoes exocytosis. (britannica.com)
  • The volatile anesthetic isoflurane differentially inhibits glutamatergic and GABAergic synaptic vesicle (SV) exocytosis by reducing presynaptic Ca 2+ influx without affecting the Ca 2+ -exocytosis relationship, but its effects on dopaminergic exocytosis are unclear. (eneuro.org)
  • Isoflurane, a widely used volatile anesthetic, inhibits voltage-gated sodium channels and differentially inhibits synaptic vesicle exocytosis depending on neurotransmitter phenotype. (eneuro.org)
  • Differentially poised vesicles underlie fast and slow components of release at single synapses. (sppin.fr)
  • This review focuses on the mechanisms by which vesicle-free miRNAs are secreted from neuroendocrine cells and will discuss potential functions of vesicle-free miRNAs and how vesicle-free miRNAs regulate cell-to-cell communication. (frontiersin.org)
  • The objective of this review is to discuss how miRNAs are released by active exocytosis and to examine the physiological functions of vesicle-free miRNAs in neuroendocrine cells. (frontiersin.org)
  • SNAP-25 is a component of the trans-SNARE complex, which accounts for membrane fusion specificity and directly executes fusion by forming a tight complex that brings the synaptic vesicle and plasma membranes together. (wikipedia.org)
  • COPII vesicles are formed in the ER membranes and mediate transport from ER to the Golgi. (jove.com)
  • calcium inflow releases neurotransmitter molecules from many vesicles by fusing the vesicle membranes to the nerve terminal membrane. (msdmanuals.com)
  • Despite its important role in exocytosis, the mechanism of vesicle merging with membrane is still poorly understood. (aps.org)
  • In pinocytosis, rather than an individual droplet of liquid traveling passively through the cell membrane , the droplet first becomes bound, or adsorbed, on the cell membrane, which then invaginates (forms a pocket) and pinches off to form a vesicle in the cytoplasm. (britannica.com)
  • Alternatively, the contents of the vesicle may be released to mix with the cytoplasm. (britannica.com)
  • The components of Opto-vTrap were expressed in the vesicles and cytoplasm. (neurosciencenews.com)
  • Dense core vesicles are usually found in the cytoplasm and these cytoplasmic vesicles must presumably translocate to the plasma membrane before release ( Zupanc, 1996 ). (rupress.org)
  • In contrast, if the tip of the electrode is inserted into the cell, the vesicles in the cytoplasm stick to the electrode and release their full contents. (news-medical.net)
  • Says Ewing: "The current transients allow us to determine how many transmitter molecules are contained in individual vesicles directly in the cytoplasm of the living cells. (news-medical.net)
  • COPI vesicles transport molecules between different parts of the Golgi body and from the Golgi back to the rough ER. (jove.com)
  • The neurotransmitter molecules are stored in the first cell in packages known as vesicles, which release their contents by fusing with the cell membrane. (elifesciences.org)
  • As reported in the journal Angewandte Chemie, zinc changes the number of messenger molecules stored in vesicles and the dynamics of their release from the cell. (news-medical.net)
  • By applying an electrode tip to the surface of the cell, we can follow the opening of an individual vesicle and compute the number of molecules released," says Ewing. (news-medical.net)
  • The amount in one vesicle (usually several thousand molecules) is a quantum. (msdmanuals.com)
  • The process of vesicular exocytosis is a fast, tightly regulated and Ca2+-triggered event mediated by SNARE complex formation. (uni-goettingen.de)
  • This release is based on exocytosis: The vesicle docks at the cell membrane, opens at the point of contact, releases part of its contents to the outside, closes, and separates from the plasma membrane so it can be refilled. (news-medical.net)
  • The SNARE complex participates in vesicle fusion, which involves the docking, priming and merging of a vesicle with the cell membrane to initiate an exocytotic event. (wikipedia.org)
  • Synaptobrevin, a protein that is a part of the vesicle-associated membrane protein (VAMP) family, and syntaxin-1 also help form the SNARE complex by each contributing a single α-helix. (wikipedia.org)
  • in this way, vesicle-free miRNA may regulate cell-to-cell communication including the regulation of gene expression and cellular signaling. (frontiersin.org)
  • To gain a more complete picture of potential differences in the regulation of SV and LDCV exocytosis, we investigated the role of different Munc13 isoforms in chromaffin cell LDCV exocytosis. (uni-goettingen.de)
  • Munc13-1 expression is low in perinatal adrenal glands, and its deletion alone did not result in significant changes in exocytosis, however its function in LDCV release became apparent in the absence of Munc13-2. (uni-goettingen.de)
  • By contrast, deletion of Baiap3, another Munc13 isoform with relatively high expression in adrenal medulla, did not lead to changes in LDCV exocytosis and its overexpression could not rescue the release deficit of Munc13-1/2-deficient cells. (uni-goettingen.de)
  • The remaining Munc13 isoforms, bMunc13-2, Munc13-3 and Munc13-4 are not expressed in perinatal adrenal glands and do not contribute to LDCV exocytosis in this cell type. (uni-goettingen.de)
  • Figure 394 from Chapter 15 (Cytoplasmic Inclusions) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. 'Omega figures' capturing synaptic vesicle exocytosis at the synaptic junction. (cellimagelibrary.org)
  • Based on the type of protein coats, these vesicles can be of three types: coat protein or COP-coated vesicles, COPI and COPII, and clathrin-coated vesicles. (jove.com)
  • COPI and COPII vesicles are composed of similar coat protein complexes called coatomers. (jove.com)
  • Coated vesicles are spherical, protein-coated carriers with a 50-100 nm diameter that mediate bidirectional transport between the ER and the Golgi. (jove.com)
  • Fusion of synaptic vesicles with the presynaptic membrane occurs in the presence of the NSF (N-ethylmaleimide-sensitive-factor) / α-SNAP (α-soluble NSF attachment protein) disassembly machinery. (nature.com)
  • have shown that another protein, synaptotagmin 7, also has a key role in the replenishment of synaptic vesicles, possibly as a sensor for calcium ions. (elifesciences.org)
  • The former is capable of binding to protein kinase C, an enzyme that binds to the membrane to regulate the speed of exocytosis. (news-medical.net)
  • The zinc species inside the cell could slow down the transport protein that loads the dopamine into the vesicles," suggests Ewing. (news-medical.net)
  • We observed reduced tissue dopamine, disrupted synaptic vesicle recycling, and defective neurotransmitter exocytosis. (bvsalud.org)
  • PA treatment attenuated the MPTP-induced upregulation of GSK-3ß, increase in cytosolic calcium concentration, decreases in the levels of DAT, VMAT2, tissue dopamine, and synaptic vesicle recycling. (bvsalud.org)
  • In addition, by selectively inhibiting granule exocytosis, we present the first evidence that epinephrine is stored in azurophilic granules. (doaj.org)
  • Here, we resolved Ca 2+ -dependent and Ca 2+ -independent synaptic vesicle (SV) replenishment pathways, and found that syt 7 plays a selective and critical role in the Ca 2+ -dependent pathway. (elifesciences.org)
  • The mode of the vesicle merging, either fully opening, stalled or kiss-and-run is determined by the physical parameters of the membrane, the vesicle and the actin filaments. (aps.org)
  • Actin- and Myosin-Dependent Vesicle Loading of Presynaptic Docking Sites Prior to Exocytosis. (sppin.fr)
  • The history of the field will be briefly reviewed, focusing on exocytosis and membrane fusion. (sfn.org)
  • After the initial fusion of the vesicle with the plasma membrane, the post-fusion pore opening is critical for the successful drug release. (aps.org)
  • In at least some synapses, transmitter release occurs by fusion of these vesicles with the presynaptic membrane, followed by exocytosis of their contents. (bvsalud.org)
  • In order to directly control the exocytotic vesicles, the research team applied a technology they previously developed in 2014, called light-activated reversible inhibition by assembled trap (LARIAT). (neurosciencenews.com)
  • For example, the replenishment of synaptic vesicles (SV) in the readily releasable pool (RRP), which can be exhausted during high frequency stimulation (HFS), plays a critical role in determining the rate and degree of short-term synaptic depression ( Wang and Kaczmarek, 1998 ). (elifesciences.org)
  • To address this problem, South Korean researchers led by Director C. Justin LEE at the Center for Cognition and Sociality within the Institute for Basic Science (IBS) and professor HEO Won Do at Korea Advanced Institute of Science and Technology (KAIST) developed Opto-vTrap, a light-inducible and reversible inhibition system that can temporarily trap vesicles from being released from brain cells. (neurosciencenews.com)
  • top right) Shining blue light causes a vesicle clusterization and complete inhibition of exocytosis. (neurosciencenews.com)
  • Munc13 is of critical importance in priming synaptic vesicles (SVs) for release, and SV exocytosis in hippocampal synapses is completely shut down in the absence of Munc13-1 and Munc13-2, whereas in the case of synaptic dense core vesicles (DCVs) the synaptic preference of DCV release is lost. (uni-goettingen.de)
  • Munc13-and SNAP25-dependent molecular bridges play a key role in synaptic vesicle priming. (mpg.de)
  • When the Opto-vTrap expressing cells or tissues are shined under blue light, the vesicles form clusters and become trapped within the cells, inhibiting the release of transmitters. (neurosciencenews.com)
  • Docking to the plasma membrane prepares vesicles for rapid release. (rupress.org)
  • Before and after the opening of the vesicle a pore forms at the point of contact with the plasma membrane. (news-medical.net)
  • A newly developed system dubbed Opto-vTrap can temporarily trap vesicles from being released from brain cells. (neurosciencenews.com)
  • Opto-vTrap directly targets transmitters containing vesicles, and it can be used in various types of brain cells, even the ones that do not respond to membrane potential changes. (neurosciencenews.com)
  • Based on our findings, we propose that A. actinomycetemcomitans promotes azurophilic granule exocytosis by neutrophils as an epinephrine source to promote bacterial survival. (doaj.org)