• 한국수산과학회지
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• 제39권2호
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• pp.94-99
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• 2006

The tadpole larvae of most ascidians have two sensory pigment cells in their brain vesicle. The anterior otolith pigment cell is sensitive to gravity, whereas the posterior ocellus pigment cell responds to light. Besides these two sensory cells, the larvae also possess another type of sensory receptor cell: hydrostatic pressure receptor (Hpr) cells. The Hpr cells have been presumed to sense hydrostatic water pressure, although no functional analysis has been performed. In larvae of the ascidian Halocynthia reretzi, the development of the Hpr cells and their structure in the brain vesicle are poorly understood. To investigate the morphology and formation of the Hpr cells, we established a monoclonal antibody, Hpr-1, that specifically recognizes Hpr cells. The Hpr-1 antigens became detectable in the brain vesicle at the late tailbud stage. Each Hpr cell projected a small globular body, connected by a short stalk, into the lumen of the brain vesicle. The brain vesicle showed remarkable left-right asymmetry. Pigment cells were located on the right side in the lumen of the brain vesicle, whereas Hpr cells were present in the left side. After metamorphosis, the Hpr cells were observed near the rudimental siphons of the juvenile.

• Journal of Yeungnam Medical Science
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• 제5권2호
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• pp.37-45
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• 1988

Phospholipase C는 second messenger로서 세포 밖의 signal transduction에 중요한 효소 이다. 본 연구에서 소의 뇌, 자궁 및 고환에서 high performance liquid chromatography(HPLC)를 이용하여 phospholipase C(PLC)를 추출하였으며 뇌에서 3개의 isozyme(F-1, F-2, F-3), 자궁과 고환에서 각각 2개의 isozyme을 얻었고 HPLC에서의 retension time을 구하였다. Homogeneity 검사를 위하여 소 brain의 각 isozyme I, II 및 III에 대한 PLC-monoclonal antibody(Mab)를 affigel에 label 시켰고 결합능(binding capacity)는 73.8~97.5%였다. PLC-Mab와 자궁 및 고환의 PLC isozyme과의 homogeneity 검사에서 binding capacity는 자궁의 F-1은 PLC III가 주이며 F-2는 DEAE column에서는 II가 주이나 phenyl column에선 I과 II가 주이고 고환에선 F-1은 PLC III가 주이고 F-2에서는 PLC II가 주인 것으로 나타났다.

• Applied Microscopy
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• 제48권3호
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• pp.55-61
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• 2018

The synaptic vesicle is a specialized structure in presynaptic terminals that stores various neurotransmitters. The actin filament has been proposed for playing an important role in mobilizing synaptic vesicles. To understand the role of actin filament on synaptic vesicle pooling, we characterized synaptic vesicles and actin filament after treatment of brain-derived neurotrophic factor (BDNF) or Latrunculin A on primary cultured neuron from rat embryo hippocampus. Western blots revealed that BDNF treatment increased the expression of synapsin I protein, but Latrunculin A treatment decreased the synapsin I protein expression. The increased expression of synapsin I after BDNF disappeared by the treatment of Latrunculin A. Three-dimensional (3D) tomography of synapse showed that more synaptic vesicles localized near the active zone and total number of synaptic vesicles increased after treatment of BDNF. But the number of synaptic vesicle was 2.5-fold reduced in presynaptic terminals and the loss of filamentous network was observed after Latrunculin A application. The treatment of Latruculin A after preincubation of BDNF group showed that synaptic vesicle number was similar to that of control group, but filamentous structures were not restored. These data suggest that the actin filament plays a significant role in synaptic vesicles pooling in presynaptic terminals.

• BMB Reports
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• 제55권4호
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• pp.204-204
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• 2022

• 대한의생명과학회지
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• 제6권3호
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• pp.165-170
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• 2000

Vacuolar (H$^{+}$)-ATPase (V-ATPase)는 multi-subunit로 구성된 단백질로서, proton pumping을 통해 세포내 산성화반응에 관여를 한다. 최근에 이 단백질이 synaptic vesicle에서도 발견된 것으로 보아 뇌 신경전달에 중요한 역할을 수행할 것으로 추정하고 있다. 우리는 흰쥐 뇌에서 분리한 mRNA를 주형으로 한 PCR 반응에서 16 kDa subunit의 V-ATPase cDHA를 클로닝할 수 있었고, 이의 염기서열 또한 결정하였다. 분리된 뇌 16 kDa V-ATPase의 coding sequence는 전체 468 bp로서 간에서 보고되었던 것과 동일한 크기였다. 단지 3' 말단의 염기 하나가 A에서 C로 바뀌어 있었는데 모두 alanine (GCA, GCC)을 지정하기 때문에 단백질의 일차구조에는 변화가 없는 것으로 확인되었다. 한편 rat brain cDNA library에서도 동일한 clone이 분리되었는데 역시 같은 부분에서 polymorphism이 발견되었고, RNA splicing 등 더 이상의 조직특이적 변화는 없었다. 본 연구는 16 kDa V-ATPase의 뇌에서의 기능과 신경말단에서의 neurotransmission 및 synaptic vesicle의 재순환 기전을 이해하는데 유용한 정보가 될 것이다.

• Bulletin of the Korean Chemical Society
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• 제28권9호
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• pp.1499-1509
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• 2007

Proteomic analyses of synaptic vesicle fraction from rat brain have been performed for the better understanding of vesicle regulation and signal transmission. Two different approaches were applied to identify proteins in synaptic vesicle fraction. First, the isolated synaptic vesicle proteins were treated with trypsin, and the resulting peptides were analyzed using a high-pressure capillary reversed phase liquid chromatography/tandem mass spectrometry (cRPLC/MS/MS). Alternatively, proteins were separated by two-dimensional gel electrophoresis (2DE) and identified by matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF/MS). Total 18 and 52 proteins were identified from cRPLC/MS-MS and 2DE-MALDI-TOF-MS analysis, respectively. Among them only 2 proteins were identified by both methods. Of the proteins identified, 70% were soluble proteins and 30% were membrane proteins. They were categorized by their functions in vesicle trafficking and biogenesis, energy metabolism, signal transduction, transport and unknown functions. Among them, 27 proteins were not previously reported as synaptic proteins. The cellular functions of unknown proteins were estimated from the analysis of domain structure, expression profile and predicted interaction partners.

• Molecules and Cells
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• 제25권1호
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• pp.7-19
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• 2008

Complexins play a critical role in the control of fast synchronous neurotransmitter release. They operate by binding to trimeric SNARE complexes consisting of the vesicle protein Synaptobrevin and the plasma membrane proteins Syntaxin and SNAP-25, which are key executors of membrane fusion reactions. SNARE complex binding by Complexins is thought to stabilize and clamp the SNARE complex in a highly fusogenic state, thereby providing a pool of readily releasable synaptic vesicles that can be released quickly and synchronously in response to an action potential and the concomitant increase in intra-synaptic $Ca^{2+}$ levels. Genetic elimination of Complexins from mammalian neurons causes a strong reduction in evoked neurotransmitter release, and altered Complexin expression levels with consequent deficits in synaptic transmission were suggested to contribute to the etiology or pathogenesis of schizophrenia, Huntington's disease, depression, bipolar disorder, Parkinson's disease, Alzheimer's disease, traumatic brain injury, Wernicke's encephalopathy, and fetal alcohol syndrome. In the present review I provide a summary of available data on the role of altered Complexin expression in brain diseases. On aggregate, the available information indicates that altered Complexin expression levels are unlikely to have a causal role in the etiology of the disorders that they have been implicated in, but that they may contribute to the corresponding symptoms.

• BMB Reports
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• 제55권1호
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• pp.20-29
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• 2022

Stem cell-based therapy is a promising approach for treating a variety of disorders, including acute brain insults and neurodegenerative diseases. Stem cells such as mesenchymal stem cells (MSCs) secrete extracellular vesicles (EVs), circular membrane fragments (30 nm-1 ㎛) that are shed from the cell surface, carrying several therapeutic molecules such as proteins and microRNAs. Because EV-based therapy is superior to cell therapy in terms of scalable production, biodistribution, and safety profiles, it can be used to treat brain diseases as an alternative to stem cell therapy. This review presents evidences evaluating the role of stem cell-derived EVs in stroke, traumatic brain injury, and degenerative brain diseases, such as Alzheimer's disease and Parkinson' disease. In addition, stem cell-derived EVs have better profiles in biocompatibility, immunogenicity, and safety than those of small chemical and macromolecules. The advantages and disadvantages of EVs compared with other strategies are discussed. Even though EVs obtained from native stem cells have potential in the treatment of brain diseases, the successful clinical application is limited by the short half-life, limited targeting, rapid clearance after application, and insufficient payload. We discuss the strategies to enhance the efficacy of EV therapeutics. Finally, EV therapies have yet to be approved by the regulatory authorities. Major issues are discussed together with relevant advances in the clinical application of EV therapeutics.

• 대한약리학회지
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• 제32권2호
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• pp.159-168
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• 1996

To determine the regulatory mechanism of phenylethanolamine N-methyltransferase (PNMT) in the adrenal gland and in central nervous system, we observed the change of enzyme activity and mRNA level of PNMT in the adrenal gland, the brain stem, and hypothalamus of rats, which were injected with two neuroleptic agents(reserpine and haloperidol ). Reserpine depleting catecholamines in presynaptic vesicle increased PNMT activities in the adrenal gland and the brain stem to 150% of the control in time-dependent manner, but not in the hypothalamus. Haloperidol blocking dopamine receptor decreased PNMT activities in the adrenal gland and the hypothalamus, but not in the brain stem. Thus, the results indicate that catecholamines inhibit synthesis of epinephrine in the brain stem and the adrenal gland, and that dopamine stimulates synthesis of epinephrine in the hypothalamus and the adrenal gland. In addition, since the change of mRNA levels were nearly in accordance with the change of activities, the transcriptional regulation of PNMT is considered the mechanism of the regulation of epinephrine neuron.

• Journal of Life Science
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• 제12권2호
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• pp.43-46
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• 2002

Kinesin Superfamily Protein 1A (KIF1A) is an anterograde monomeric motor transporting a subset of synaptic vesicle precursors and plays an important role in neuronal function and survival. Here, f have used the yeast two-hybrid system to identify the proteins that interacts with the tail region of KIF1A. Calmodulin was found to interact specifically with the tail region of KIF1A. Calmodulin regulates many diverse cellular functions by modulating the activity of the proteins that interact with it. KIF1A interacts with calmodulin in the yeast two-hybrid assay, which is proved by immunoprecipitation with calmodulin in brain fraction. These results indicate that KIF1A is associated with calmodulin, suggesting that calmodulin may be a key role in the regulation of anterograde transport of synaptic 1 vesicle precursors.