• ALGAE
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• 제36권4호
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• pp.315-326
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• 2021

Ion channels are membrane protein complexes mediating passive ion flux across the cell membranes. Every organism has a certain set of ion channels that define its physiology. Dinoflagellates are ecologically important microorganisms characterized by effective physiological adaptability, which backs up their massive proliferations that often result in harmful blooms (red tides). In this study, we used a bioinformatics approach to identify homologs of known ion channels that belong to 36 ion channel families. We demonstrated that the versatility of the dinoflagellate physiology is underpinned by a high diversity of ion channels including homologs of animal and plant proteins, as well as channels unique to protists. The analysis of 27 transcriptomes allowed reconstructing a consensus ion channel repertoire (channelome) of dinoflagellates including the members of 31 ion channel families: inwardly-rectifying potassium channels, two-pore domain potassium channels, voltage-gated potassium channels (K_v), tandem K_v, cyclic nucleotide-binding domain-containing channels (CNBD), tandem CNBD, eukaryotic ionotropic glutamate receptors, large-conductance calcium-activated potassium channels, intermediate/small-conductance calcium-activated potassium channels, eukaryotic single-domain voltage-gated cation channels, transient receptor potential channels, two-pore domain calcium channels, four-domain voltage-gated cation channels, cation and anion Cys-loop receptors, small-conductivity mechanosensitive channels, large-conductivity mechanosensitive channels, voltage-gated proton channels, inositole-1,4,5-trisphosphate receptors, slow anion channels, aluminum-activated malate transporters and quick anion channels, mitochondrial calcium uniporters, voltage-dependent anion channels, vesicular chloride channels, ionotropic purinergic receptors, animal volage-insensitive cation channels, channelrhodopsins, bestrophins, voltage-gated chloride channels H⁺/Cl^- exchangers, plant calcium-permeable mechanosensitive channels, and trimeric intracellular cation channels. Overall, dinoflagellates represent cells able to respond to physical and chemical stimuli utilizing a wide range of G-protein coupled receptors- and Ca²⁺-dependent signaling pathways. The applied approach not only shed light on the ion channel set in dinoflagellates, but also provided the information on possible molecular mechanisms underlying vital cellular processes dependent on the ion transport.

• The Korean Journal of Physiology and Pharmacology
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• 제27권4호
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• pp.311-323
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• 2023

Ion homeostasis, which is regulated by ion channels, is crucial for intracellular signaling. These channels are involved in diverse signaling pathways, including cell proliferation, migration, and intracellular calcium dynamics. Consequently, ion channel dysfunction can lead to various diseases. In addition, these channels are present in the plasma membrane and intracellular organelles. However, our understanding of the function of intracellular organellar ion channels is limited. Recent advancements in electrophysiological techniques have enabled us to record ion channels within intracellular organelles and thus learn more about their functions. Autophagy is a vital process of intracellular protein degradation that facilitates the breakdown of aged, unnecessary, and harmful proteins into their amino acid residues. Lysosomes, which were previously considered protein-degrading garbage boxes, are now recognized as crucial intracellular sensors that play significant roles in normal signaling and disease pathogenesis. Lysosomes participate in various processes, including digestion, recycling, exocytosis, calcium signaling, nutrient sensing, and wound repair, highlighting the importance of ion channels in these signaling pathways. This review focuses on different lysosomal ion channels, including those associated with diseases, and provides insights into their cellular functions. By summarizing the existing knowledge and literature, this review emphasizes the need for further research in this field. Ultimately, this study aims to provide novel perspectives on the regulation of lysosomal ion channels and the significance of ion-associated signaling in intracellular functions to develop innovative therapeutic targets for rare and lysosomal storage diseases.

• 동의생리학회지
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• 제14권2호통권20호
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• pp.67-82
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• 1999

The effects of Bogi, Boyang and Onri herbs on glutamte receptor, and the regulatory mechanism of cAMP-protein kinase on the ion currents activated by Bogi, Boyang and Onri herbs using nystatin-perforated patch clamp were investigated and the following results were obtained. Ginseng radix and Astragali radix, Cervi cornu and Boshniakiae herba, and Aconiti tuber and Zingiberis rhizoma were chosen as Bogi, Boyang and Onri herbs respectively. 1. The ion currents activated by $10^{-5}M$ of glycine were used as controls. The magnitudes of the ion currents by the above named herbs were as follows; Cervi cornu>Astragali radix>Aconiti tuber>Zingiberis rhizoma>Ginseng radix>Boshniakiae herba. 2. The magnitudes of the ion currents by $10^{-5}M$ of glutamate pre-treated with 0.01 mg/ml of Bogi, Boyang and Onri herbs were sharply decreased. 3. The activity of ion channels activated by Bogi herbs pre-treated with $10^{-7}M$ of staurosporin, an inhibitor of protein kinase, for thirty seconds was observed as the experiment proceeded. Staurosporin brought about dephosphorylation of ion channels. Hence, while the activity of ion channels activated by Ginseng radix was decreased, the activity of ion channels activated by Astragali radix was increased, as time went by. 4. The activity of ion channels activated by Boyang herbs pre-treated with $10^{-7}M$ of staurosporin, an inhibitor of protein kinase and an dephosphorylating agent of ion channels, for thirty seconds was investigated. While the activity of ion channels activated by Cervi cornu was increased, the activity of ion channels activated by Boshniakiae herba was initially increased then sharply decreased. 5, The activity of ion channels activated by Onri herbs pre-treated with $10^{-7}M$ of staurosporin, an inhibitor of protein kinase and an dephosphorylating agent of ion channels, for thirty seconds was investigated. While the activity of ion channels activated by Aconiti tuber was increased, that of ion channels activated by Zingiberis rhizomal sharply declined.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2003년도 추계 총회 및 학술대회
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• pp.6-6
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• 2003

• Journal of Ginseng Research
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• 제29권1호
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• pp.19-26
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• 2005

The last two decades have shown a marked expansion in publications of diverse effects of Panax ginseng. Ginsenosides, as active ingredients of Panax ginseng, are saponins found in only ginseng. Recently, a line of evidences shows that ginsenosides regulate various types of ion channel activity such as $Ca^{2+},\;K^+,\;Na^+,\;Cl^-$, or ligand gated ion channels (i.e. $5-HT_3$, nicotinic acetylcholine, or NMDA receptor) in neuronal, non-neuronal cells, and heterologously expressed cells. Ginsenosides inhibit voltage-dependent $Ca^{2+},\;K^+,\;and\;Na^+$ channels, whereas ginsenosides activate $Ca^{2+}-activated\;Cl^-\;and\;Ca^{2+}-activated\;K^+$ channels. Ginsenosides also inhibit excitatory ligand-gated ion channels such as $5-HT_3$, nicotinic acetylcholine, and NMDA receptors. This review will introduce recent findings on the ginsenoside-induced differential regulations of ion channel activities and will further expand the possibilities how these ginsenoside-induced ion channel regulations are coupled to biological effects of Panax ginseng.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2005년도 창립30주년기념 추계 학술대회 및 정기총회
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• pp.32-40
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• 2005

The last two decades have shown a marked expansion in publications of diverse effects of Panax ginseng. Ginsenosides, as active ingredients of Panax ginseng, are saponins found in only ginseng. Recently, a line of evidences shows that ginsenosides regulate various types of ion channel activity such as Ca$^{2+}$, K$^+$, Na$^+$, Cl$^-$, or ligand gated ion channels (i.e. 5-HT$_3$, nicotinic acetylcholine, or NMDA receptor) in neuronal, non-neuronal cells, and heterologously expressed cells. Ginsenosides inhibit voltage-dependent Ca$^{2+}$, K$^+$, and Na$^+$ channels, whereas ginsenosides activate Ca$^{2+}$-activated Cl$^-$ and Ca$^{2+}$-activated K$^+$ channels. Ginsenosides also inhibit excitatory ligand-gated ion channels such as 5-HT$_3$. nicotinic acetylcholine, and NMDA receptors. This presentation will introduce recent findings on the ginsenoside-induced differential regulations of ion channel activities as a ligand as other drugs do.

• BMB Reports
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• 제44권10호
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• pp.635-646
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• 2011

Due to its high external and low internal concentration the $Ca^{2+}$ ion is used ubiquitously as an intracellular signaling molecule, and a great many $Ca^{2+}$-sensing proteins have evolved to receive and propagate $Ca^{2+}$ signals. Among them are ion channel proteins, whose $Ca^{2+}$ sensitivity allows internal $Ca^{2+}$ to influence the electrical activity of cell membranes and to feedback-inhibit further $Ca^{2+}$ entry into the cytoplasm. In this review I will describe what is understood about the $Ca^{2+}$ sensing mechanisms of the three best studied classes of $Ca^{2+}$-sensitive ion channels: Large-conductance $Ca^{2+}$-activated $K^+$ channels, small-conductance $Ca^{2+}$-activated $K^+$ channels, and voltage-gated $Ca^{2+}$ channels. Great strides in mechanistic understanding have be made for each of these channel types in just the past few years.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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• pp.581.1-581
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• 2001

Trigeminal nerve functions movement and sensation on orofacial region. Therefore, it is very important in dental clinic. Neurons with their cell bodies in trigeminal ganglion of trigeminal nerve root are primary sensory neurons and playa role of tactile sense, pressure, vibration and pain of orofacial area. Transmission of these senses depends on ion channels, we know that trigeminal ganglion neuron exists many kind of ion channels. Methods of definition on ion channel are several, but in this study we use immunostaining for detection of ion channels.(omitted)

• 대한약리학회:학술대회논문집
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• 대한약리학회 2006년도 The 6th Congress of the Federation of Asian and Oceanian Physiological Societies
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• pp.109.2-109.2
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• 2006

• Journal of Ginseng Research
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• 제32권2호
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• pp.99-106
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• 2008

A ligand - whether an endogenous hormone, neurotransmitter, exogenous toxin or synthetic drug - binds to plasma membrane proteins (e.g., ion channels, receptors or other functional proteins) to exert its physiological or pharmacological effects. Ligands can also have functional groups, showing stereospecificity for interaction sites on their counterpart plasma membrane proteins. Previous reports have shown that the ginsenoside Rg$_3$, a bioactive ginsenoside, meets these criteria in that: 1) an aliphatic side chain of $Rg_3$ plays a role as a functional group, 2) Rg$_3$ regulates voltage- and ligand-gated ion channels in a stereospecific manner with respect to carbon-20, and 3) $Rg_3$ regulates subsets of ligand-gated and voltage-gated ion channels through specific interactions with identified amino acid residues inside the channel pore, in the outer pore entryway, or in toxin binding sites. Rg$_3$, therefore, could be a candidate for a novel ginseng-derived glycosidic ligand regulating ion channels and receptors. This review will examine how Rg$_3$ regulates voltage-gated and ligand-gated ion channels through interactions with its target proteins in the plasma membrane. Hopefully, this review will advance understanding of ginseng pharmacology at the cellular and molecular levels.