• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.44-44
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• 2001

Neuroendocrine (NE) cells are abundant in the prostate at birth and then disappear from the peripheral zone, only to reappear during puberty, after which their number slowly increases during adult life. NE cells are believed to play an important role in prostate growth and differentiation. The present study was undertaken to investigate the characteristics of ion channels existing in NE cells of rat prostate gland.(omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.34-34
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• 1998

Tolaasin is a channel forming bacterial toxin produced by Pseudomonas tolaasii and causes a brown blotch disease on cultivated oyster mushrooms. When tolaasin molecules form channels in the membranes of mushroom cells, they destroy cellular membrane structure, known as 'colloid osmotic lysis'. In order to understand the molecular mechanisms forming membrane channels by tolaasin molecules, we have investigated the electrophysiological characteristics of tolaasin-induced channels in lipid bilayer.(omitted)

• Animal cells and systems
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• v.3 no.2
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• pp.181-185
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• 1999

Xenopus oocyte is one of the widely used heterologous expression systems of ion channels for electrophysiological studies. Here we describe a new method in which cRNA produced by polymerase chain reaction (PCR) and in vitro transcription is injected to express ion channels in oocytes. This method enables us (1) to eliminate all or a part of the untranslated region of the cDNA and to replace it with a known sequence which helps increase the expression level in oocytes, and (2) to use the PCR product for in vitro transcription without subcloning. Using this method, the expression level of one of the neuronal nicotinic acetylcholine receptors (nAChRs) $\alpha$$_{6}$ subtype in oocytes was systematically increased by more than 100-fold, which was confirmed both by the $\alpha$-Bungarotoxin ($\alpha$,/TEX>Bgt) binding assay and the current measurement.t.

• Journal of Ginseng Research
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• v.43 no.2
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• pp.163-171
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• 2019

Common features of neurodegenerative diseases (NDDs) include progressive dysfunctions and neuronal injuries leading to deterioration in normal brain functions. At present, ginseng is one of the most frequently used natural products. Its use has a long history as a cure for various diseases because its extracts and active compounds exhibit several pharmacological properties against several disorders. However, the pathophysiology of NDDs is not fully clear, but researchers have found that various ion channels and specific signaling pathways might have contributed to the disease pathogenesis. Apart from the different pharmacological potentials, ginseng and its active compounds modulate various ion channels and specific molecular signaling pathways related to the nervous system. Here, we discuss the signal modulating potential of ginseng and its active compounds mainly focusing on those relevant to NDDs.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1097-1100
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• 2011

A toxin produced by Pseudomonas tolaasii, tolaasin, causes brown blotch disease in mushrooms. Tolaasin forms pores on the cellular membrane and destroys cell structure. Inhibiting the ability of tolaasin to form ion channels may be an effective method to protect against attack by tolaasin. However, it is first necessary to elucidate the three-dimensional structure of the ion channels formed by tolaasin. In this study, the structure of the tolaasin ion channel was determined in silico based on data obtained from nuclear magnetic resonance experiments.

• BMB Reports
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• v.53 no.3
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• pp.125-132
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• 2020

Transient receptor potential (TRP) channels comprise a diverse family of ion channels, the majority of which are calcium permeable and show sophisticated regulatory patterns in response to various environmental cues. Early studies led to the recognition of TRP channels as environmental and chemical sensors. Later studies revealed that TRP channels mediated the regulation of intracellular calcium. Mutations in TRP channel genes result in abnormal regulation of TRP channel function or expression, and interfere with normal spatial and temporal patterns of intracellular local Ca²⁺ distribution. The resulting dysregulation of multiple downstream effectors, depending on Ca²⁺ homeostasis, is associated with hallmarks of cancer pathophysiology, including enhanced proliferation, survival and invasion of cancer cells. These findings indicate that TRP channels affect multiple events that control cellular fate and play a key role in cancer progression. This review discusses the accumulating evidence supporting the role of TRP channels in tumorigenesis, with emphasis on prostate cancer.

• BMB Reports
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• v.44 no.9
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• pp.559-565
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• 2011

Protein kinase C (PKC) is a central enzyme that modulates numerous biological functions. For this reason, specific PKC inhibitors/activators are required to study PKC-related signaling mechanisms. To date, although many PKC inhibitors have been developed, they are limited by poor selectivity and nonspecificity. In this review, we focus on the nonspecific actions of PKC inhibitors on cardiovascular ion channels in addition to their PKC-inhibiting functions. The aim of this paper is to urge caution when using PKC inhibitors to block PKC function. This information may help to better understand PKC-related physiological/biochemical studies.

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.39-39
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• 1998

Stretch-activated ion channel that is open by mechanical stress applied on the cell membrane is one of the classes of ion channels. Other than stretch-activated channel itself, it has been also reported that a variety of ion channels could be modulated by a mechanical cell stretch.(omitted)

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.287-299
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• 2014

Bicarbonate anion ($HCO_3{^-}$) takes the role of major buffer systems in our body by maintaining the pH at 7.4. Epithelial $HCO_3{^-}$ secretion also hydrolyzes the mucus which protects body from noxious infections. It has been widely known that such infections are closely related to $HCO_3{^-}$ permeability through membrane and, thus, increasing the $HCO_3{^-}$ permeability is essential. To evaluate the $HCO_3{^-}$ permeability through ion channels, the free energy changes relevant to ion pumping are calculated with the Integral Equation Formalism-PCM (IEF-PCM) theory. Molecular structures of various anions including $HCO_3{^-}$ were optimized with the density functional theory at the level of B3LYP/6-311++G(d,p) in gas and solution phase. In addition, the anion permeability is significantly influenced by the relative size of the anion and pore. We introduce a shifted volume factor model that describes the pore size effect when the charged solutes transfer through ion channels. We found excellent agreement between experimental and calculated permeability when our novel model of the size effect was taken into account to.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.1093-1097
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• 1995

A micro ion drag pump with planar electrodes on a glass substrate is fabricated and tested. the pump consisted of a 2- dimensional electrode pair array is driven by DC voltage using unipolar conduction. Ethy alcohol is pumped in both directions, and the flow rate and the pressure are measured, in channels of depth 100 .mu m or 200 .mu. m and width fixed at 3mm. It is found that the pump could be fabricated easily and at lower cost than the micro ion drag pumps previously investigated.