• 한국발생생물학회지:발생과생식
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• 제22권2호
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• pp.143-153
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• 2018

The large extracellular domain of glycoprotein hormone receptors is a unique feature within the G protein-coupled receptors (GPCRs) family. After interaction with the hormone, the receptor becomes coupled to Gs, which, in turn stimulates adenylyl cyclase and the production of cAMP. Potential phosphorylation sites exist in the C-terminal region of GPCRs. The experiments described herein represent attempts to determine the functions of the eel follicle-stimulating hormone receptor (eelFSHR). We constructed a mutant of eelFSHR, in which the C-terminal cytoplasmic tail was truncated at residue 614 (eelFSHR-t614). The eelFSHR-t614 lacked all potential phosphorylation sites present in the C-terminal region of eelFSHR. In order to obtain the eelFSHR ligand, we produced recombinant follicle-stimulating hormone ($rec-eelFSH{\beta}/{\alpha}$) in the CHO-suspension cells. The expression level was 2-3 times higher than that of the transient expression of eelFSH in attached CHO-K1 cells. The molecular weight of the $rec-eelFSH{\beta}/{\alpha}$ protein was identified to be approximately 34 kDa. The cells expressing eelFSHR-t614 showed an increase in agonist-induced cAMP responsiveness. The maximal cAMP responses of cells expressing eelFSHR-t614 were lower than those of cells expressing eelFSHR-wild type (eelFSHR-WT). The $EC_{50}$ following C-terminal deletion in CHO-K1 cells was approximately 60.4% of that of eelFSHR-WT. The maximal response in eelFSHR-t614 cells was also drastically lower than that of eelFSHR-WT. We also found similar results in PathHunter Parental cells expressing ${\beta}$-arrestin. Thus, these data provide evidence that the truncation of the C-terminal cytoplasmic tail phosphorylation sites in the eelFSHR greatly decreased cAMP responsiveness and maximal response in both CHO-K1 cells and Path-Hunter Parental cells expressing ${\beta}$-arrestin.

• Journal of Ginseng Research
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• 제35권1호
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• pp.92-103
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• 2011

Ginseng has been used as a general tonic agent to invigorate human body. In the present study, we isolated novel glycolipoproteins from ginseng that activate $Ca^{2+}$-activated $Cl^-$ channel (CaCC) in Xenopus oocytes and transiently increase intracellular free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) in mouse Ehrlich ascites tumor cells. We named the active ingredients as gintonin. Gintonin exists in at least six different forms. The native molecular weight of gintonin is about 67 kDa but its apparent molecular weight is about 13 kDa, indicating that gintonin might be a pentamer. Gintonin is rich in hydrophobic amino acids. Its main carbohydrates are glucose and glucosamine. Its lipid components are linoleic, palmitic, oleic, and stearic acids. Gintonin actions were blocked by U73122, a phospholipase C inhibitor, 2-aminoethxydiphenyl borate, an inositol 1,4,5-trisphosphate receptor antagonist, or bis (o-aminophenoxy) ethane-N,N,N0,N0-tetracetic acid acetoxymethyl ester, a membrane permeable $Ca^{2+}$ chelator. In the present study, we for the first time isolated novel gintonin and showed the signaling pathways on gintonin-mediated CaCC activations and transient increase of $[Ca^{2+}]_i$. Since $[Ca^{2+}]_i$ as a second messenger plays a pivotal role in the regulation of diverse $Ca^{2+}$-dependent intracellular signal pathways, gintonin-mediated regulations of $[Ca^{2+}]_i$ might contribute to biological actions of ginseng.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.109-113
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• 2001

Oxidized low-density lipoprotein (oxLDL) has been shown to modulate transactivations by the peroxisome proliferator activated receptor (PPAR)$\gamma$ and nuclear factor-kappa B (NF$\kappa$B). In this study, the oxLDL signaling pathways involved with the NF$\kappa$B transactivation were investigated by utilizing a reporter construct driven by three upstream NF$\kappa$B binding sites, and various pharmacological inhibitors. OxLDL and its constituent lysophophatidylcholine (lysoPC) induced a rapid and transient increase of intracellular calcium and stimulated the NF-KB transactivation in resting RAW264.7 macrophage cells in an oxidation-dependent manner. The NF$\kappa$B activation by oxLDL or lysoPC was inhibited by protein kinase C inhibitors or an intracellular calcium chelator. Tyrosine kinase or PI3 kinase inhibitors did not block the NF$\kappa$B transactivation. Furthermore, the oxLDL-induced NF$\kappa$B activity was abolished by the PPAR$\gamma$ ligands. When the endocytosis of oxLDL was blocked by cytochalasin B, the NF$\kappa$B transactivation by oxLDL was synergistically increased, while PPAR transactivation was blocked. These results suggest that oxLDL activates NF-$\kappa$B in resting macrophages via protein kinase C- and/or calcium-dependent pathways, which does not involve the endocytic processing of oxLDL. The endocytosis-dependent PPAR$\gamma$ activation by oxLDL may function as an inactivation route of the oxLDL induced NF$\kappa$B signal. Short heterodimer partner (SHP), specifically expressed in liver and a limited number of other tissues, is an unusual orphan nuclear receptor that lacks the conventional DNA-binding domain. In this work, we found that SHP expression is abundant in murine macrophage cell line RAW 264.7 but suppressed by oxLDL and its constituent I3-HODE, a ligand for peroxisome proliferator-activated receptor y. Furthermore, SHP acted as a transcription coactivator of nuclear factor-$\kappa$B (NF$\kappa$B) and was essential for the previously described NF$\kappa$B transactivation by lysoPC, one of the oxLDL constituents. Accordingly, NF$\kappa$B, transcriptionally active in the beginning, became progressively inert in oxLDL-treated RAW 264.7 cells, as oxLDL decreased the SHP expression. Thus, SHP appears to be an important modulatory component to regulate the transcriptional activities of NF$\kappa$B in oxLDL-treated, resting macrophage cells.

• Korean Journal of Acupuncture
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• 제26권4호
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• pp.195-209
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• 2009

Objectives : Transient inflammation has been demonstrated to alter visceral sensory function in animal models and acute mucosal inflammation may precede the manifestation of visceral hyperalgesia. Thus in this study we compared effects of herbal acupuncture of Nidus Vespae (NV) applied to the different acupoints in the acute colitis induced by trinitrobenzenesulphonic acid (TNBS) intracolonic injection in rats. Methods : In Male Sprague-Dawley rats, weighing 250 ~ 400 g, TNBS (5 mg/kg) was infused intrarectally through a silicon rubber catheter into the anus under isoflurane anaesthesia. Under general anesthesia, acupoints of LI4 (Hapkok), SI25 (Cheonchu), ST36 (Joksamni), BL25 (Daejangsu) were intramuscularly injected by NV. Expressions of cFos protein in the periaqueductal gray (PAG), locus coeruleus (LC), nucleus of solitary tract (Sol), and the 6th lumbar spinal cord (L6 s.c.) were observed at 24 hrs after TNBS induced colitis by immunohistochemistry. Results : The expression of c-Fos protein in L6 s.c., Sol, LC and PAG increased 24 hrs after TNBS injection into colorectum as compared to normal group. NV herbal acupuncture also inhibited the expression of c-Fos protein in Sol but not L6 s.c., LC, and PAG. NV to ST36 inhibited significantly the c-Fos expression in Sol and PAG. NV to ST25 inhibited the c-Fos protein expression all over the observation area. NV to BL25 showed the inhibitory effects in the areas except LC. Whether or not a role of endogenous opioids, intrathecal injection of naltrexone (30 ug / 30 ul) was applied before the 2nd herbal acupuncture treatment 24 hrs after TNBS-induced colitis in rat. Naltrexone reversed the inhibition of c-Fos protein expression in the spinal cord and brainstem under different conditions such as type of herbal acupuncture compound and choice of acupoint. Conclusions : In summary, these data show that herbal acupuncture of NV inhibits signal pathways such as spinal cord and brain stem ascending hypersensitivity of colorectum after TNBS induced colitis. This effect may be mediated by acupoints through the endogenous opioid system involving the pain modulation.

• 한국정보통신학회논문지
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• 제12권5호
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• pp.879-886
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• 2008

본 논문에서는 저전압 차동 신호(Low-Voltage Differential Signaling, LVDS) 전송방식의 응용을 위한 차동 전송 접속 경로의 분석 및 설계 최적화 방법을 제안한다. 차동 전송 경로 및 저전압 스윙 방법의 발전으로 인해 LVDS 방식은 데이터 통신 분야, 고해상도 디스플레이 분야, 평판 디스플레이 분야에서 매우 적은 소비전력, 개선된 잡음 특성 및 고속 데이터 전송률을 제공한다. 본 논문은 차동 유연성 인쇄회로 보드(flexible printed circuit board, FPCB) 전송선에서 선폭, 선두께 및 선 간격과 같은 전송선 설계 변수들의 최적화 기법을 이용하여 직렬 접속된 전송선에서 발생하는 임피던스 부정합과 신호왜곡을 감소시키기 위해 개선 모델과 새로이 개발된 수식을 제안한다. 이러한 차동 FPCB 전송선의 고주파 특성을 평가하기 위해 주파수 영역에서 전파(full-wave) 전자기 시뮬레이션, 시간영역 시뮬레이션 및 S 파라미터 시뮬레이션을 각각 수행하였다. $17.5{\mu}m$과 $35{\mu}m$의 전송선의 경우, 전극 폭에서의 약 10% 변화가 차동 임피던스에서의 약 6%와 5.6%의 변화를 각각 보였으나, 전송선 간 간격은 차동 및 특성 임피던스에서의 영향을 주지 않음을 확인하였다. 또한 전송선 간격이 증가할수록 상호 인덕턴스 및 커패시턴스가 감소하기 때문에 누화 잡음을 감소시키기 위해 신호 전송선간의 간격을 $180{\mu}m$ 이상 유지 해야함을 확인하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제23권2호
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• pp.151-159
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• 2019

Pruritus (itching) is classically defined as an unpleasant cutaneous sensation that leads to scratching behavior. Although the scientific criteria of classification for pruritic diseases are not clear, it can be divided as acute or chronic by duration of symptoms. In this study, we investigated whether skin injury caused by chemical (contact hypersensitivity, CHS) or physical (skin-scratching stimulation, SSS) stimuli causes initial pruritus and analyzed gene expression profiles systemically to determine how changes in skin gene expression in the affected area are related to itching. In both CHS and SSS, we ranked the Gene Ontology Biological Process terms that are generally associated with changes. The factors associated with upregulation were keratinization, inflammatory response and neutrophil chemotaxis. The Kyoto Encyclopedia of Genes and Genomes pathway shows the difference of immune system, cell growth and death, signaling molecules and interactions, and signal transduction pathways. Il1a, Il1b and Il22 were upregulated in the CHS, and Tnf, Tnfrsf1b, Il1b, Il1r1 and Il6 were upregulated in the SSS. Trpc1 channel genes were observed in representative itching-related candidate genes. By comparing and analyzing RNA-sequencing data obtained from the skin tissue of each animal model in these characteristic stages, it is possible to find useful diagnostic markers for the treatment of itching, to diagnose itching causes and to apply customized treatment.

• Nuclear Engineering and Technology
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• 제26권1호
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• pp.41-53
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• 1994

1991년 2월 미하마원전에서 발생한 증기발생기 세관 파열사고에 대한 경험을 바탕으로, 본 사고에 대한 고리 1호기의 대처능력을 평가하기 위하여 해석을 수행하였다. 고리 1호기의 계통설계 및 운전조건은 미하마 2호기와 아주 유사하기 때문에 고리 1호기에서 발생한 가상의 증기발생기 세관 파열사고시의 사고경위 및 전개에 대한 평가가 필요하였다. 해석은 고리 1호기 EOP를 근거로 현실적으로 가능하게 수행되었다. 해석결과, 파열된 세관을 통한 누출은 사고후 약 40분 후에 정지되었으며, 고리 1호기는 유사한 증기발생기 세관 파열사고의 경우 충분한 대처능력이 있음을 보였다. 그러나, SI 신호작동후 소외전원으로 부터의 비안전등급 AC전원으로 단절되는 설계에 대한 재고가 필요하며, EOP의 운전절차가 운전원의 적절한 판단을 요구하기에는 다소 충분치 못함을 보였다. 또한 미하마 원전의 사고를 실험적으로 모사한 LSTF의 실험결과를 이용 해석코드인 RELAP5/MOD3의 평가능력에 대하여 해석을 수행하였다. 해석결과 코드는 사고 초기의 누설량 예측을 제외하고는 일반적으로 실험결과와 잘 일치하고 있음을 보였다.

• 대한소아치과학회지
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• 제28권2호
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• pp.238-246
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• 2001

본 실험은 탁월한 골유도능으로 관심의 대상이 되고 있는 BMP의 세포내 신호 전달자로 알려진 Smad 1과 Smad 5가 조골세포 초기 분화표지인자인 ALP 유전자의 발현에 미치는 영향 및 그 조절기전을 알아보고자 하였다. BMP 처리 없이도 Smad에 의해 ALP가 발현되는가를 알아보기 위해 Smad 1과 Smad 5가 각각 stably transfection된 C2C12 세포를 3일간 배양후 histochemical assay를 하였고, Smad 1과 Smad 5의 expression vector와 ALP promoter vector를 transient co-transfection한 후 ALP promoter activity를 측정하였다. Smad에 의한 BMP의 효과를 알아보기 위해서 100ng/ml의 BMP-2를 처리한 군과 처리하지 않은 군으로 나누어 세포를 배양한후 ALP 유전자의 발현을 northern blot analysis로 확인 하였다. Smad가 ALP 유전자의 발현을 직접적으로 조절하는가를 알아보기 위해서는 단백질 합성억제제인 cycloheximide를 전처리하여 ALP 유전자의 발현을 northern blot analysis하였다. 이상의 실험결과 다음과 같은 결론을 얻었다. $\cdot$ Smad 1과 Smad 5가 과발현된 세포에서는 BMP 처리없이도 ALP가 발현된다. $\cdot$ Smad 1과 Smad 5가 과발현된 세포에서 BMP 처리후 ALP 발현 증가율이 대조군 보다 현저히 높게 나타나 Smad가 BMP 효과를 증가시킨다는 것을 알 수 있다. $\cdot$ Smad는 새로운 단백질의 합성을 통해 ALP 유전자를 발현시킨다.

• 생명과학회지
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• 제32권11호
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• pp.833-840
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• 2022

만성 염증은 종양의 발생 및 진행과 밀접하게 연관되어 있다. 핵인자 kappa B (NF-κB)는 5개의 전사인자로 구성되며 염증 반응에 필수적인 역할을 한다. 다양한 암에서 NF-κB의 조절장애가 보고되고 있으며 NF-κB 조절이 암 치료에 있어 핵심 표적이 된다. 본 연구에서는 CDC Like Kinase 3 (CLK3)를 NF-κB 신호전달 경로를 조절하는 새로운 키네이스임을 확인하였다. 우리는 CLK3가 정규 및 비정규 NF-κB 신호전달경로를 억제하는 것을 밝혔다. CLK3 과발현 또는 knock-down 세포주를 이용한 루시퍼레이즈 분석 결과, 이 키네이스는 TNFα와 PMA가 유도하는 정규 NF-κB 신호전달경로 활성을 억제하였다. 또한 CLK3 과발현은 잘 알려진 비정규 NF-κB 신호경로 유도제인 NF-κB-inducing kinase (NIK) 또는 CD40에 의한 NF-κB 활성을 저해하였다. 추가적으로 CLK3의 NF-κB 신호전달 저해기전을 설명하고자 TNFα 처리 후 웨스턴 블롯 분석으로 이 키네이스 영향권 내에 있는 NF-κB 신호경로 분자들을 식별하였다. 그 결과 CLK3가 TAK1, IKKα/α, p65, IκBα 및 ERK1/2-MAPK의 인산화/활성화를 저해하여 TNFα 처리로 유도된 NF-κB 및 MAPK 신호경로를 모두 억제함을 밝혔다. 앞으로의 연구는 CLK3가 정규 및 비정규 NF-κB 경로를 억제하는 기작을 밝히는데 초점을 맞출 것이다. 위 연구 결과들을 토대로 CLK3가 NF-κB 신호전달경로의 새로운 음성 조절자로써 기능함을 제시하였다.