• Biotechnology and Bioprocess Engineering:BBE
• /
• v.10 no.1
• /
• pp.16-22
• /
• 2005

cDNA for oxidosqualene cyclase was cloned by a homology-based PCR method and sequenced from Centella asiatica. In a sequences analysis, the putative polypeptide of C. asiatica cycloartenol synthase (CaCYS) deduced from the 2,274 bp nucleotide sequence, consisted of 758 amino acids and had a molecular mass of 86.3 kD. The predicted amino acid sequence exhibited high homology to that of PNX (cycloartenol synthase) from Panax ginseng ($89\%$). Southern blot analysis suggests that CaCYS may be present in one copy of the C. asiatica genome. If methyl jasmonate (MJ) is applied exogenously to plants, not only triterpene saponins are accumulated in tissues, but also it produces effects such as growth inhibition and the promotion of ethylene production. In order to investigate the effect of MJ and thidiazuron (TDZ), a cytokinin that plays a role as an antisenescence agent in several plants, on the level of CaCYS mRNA, we performed northern blot analysis. When MJ is alone treated by adding to culture medium, CaCYS transcripts were inhibited. However, sustained levels of the expression of CaCYS, by adding TDZ to the medium despite MJ treatments, were demonstrated in C. asiatica leaves.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.12
• /
• pp.1683-1690
• /
• 2013

The cyclic AMP receptor protein (CRP) homolog, GlxR, controls the expression of several genes involved in the regulation of diverse physiological processes in Corynebacterium glutamicum. In silico analysis has revealed the presence of glxR binding sites upstream of genes ptsG, adhA, and ald, encoding glucose-specific phosphotransferase system protein, alcohol dehydrogenase (ADH), and acetaldehyde dehydrogenase (ALDH), respectively. However, the involvement of the GlxR-cAMP complex on the expression of these genes has been explored only in vitro. In this study, the expressions of ptsG, adhA, and ald were analyzed in detail using an adenylate cyclase gene (cyaB) deletion mutant and glxR deletion mutant. The specific activities of ADH and ALDH were increased in both the mutants in glucose and glucose plus ethanol media, in contrast to the wild type. In accordance, the promoter activities of adhA and ald were derepressed in the cyaB mutant, indicating that glxR acts as a repressor of adhA. Similarly, both the mutants exhibited derepression of ptsG regardless of the carbon source. These results confirm the involvement of GlxR on the expression of important carbon metabolic genes; adhA, ald, and ptsG.

• Proceedings of the Ginseng society Conference
• /
• 1984.09a
• /
• pp.107-111
• /
• 1984

쥐의 뇌에서 추출한 입자상 아데닐산 고리화효소와 입자상 구아닐산효소의 활동성에 미치는 몇 가지 긴세노시드들의 효과를 조사하였다. $Rb_{2},\;Rb_{1}$, Rc 및 Re들과 같은 약간의 진세노사이드들이 두 효소들의 활동성을 상반적으로 변화시키는 것을 관찰하였다. 아데닐산 고리화효소와 구아닐산 고리화효소의 활동성에 미치는 GMP 및 AMP의 조절작용을 조사하였다. 긴세노시드 Rd로 방해된 아데닐산고리화효소는 GMP를 첨가함에 따라서 활성화되었다. 마찬가지로. 긴세노시드 $Rb_{2}$로 방해된 아데닐산 고리화효소도 GMP에 의해서 활성화되었다. 다른 한편, 긴세노시드 Rc로 활성화된 구아닐산 고리화효소는 AMP 또는 GMP를 첨가함에 따라서 방해되었다. 진세노사이드 $Rb_{2}$ 도파민 사이에는 아데닐산 고리화효소 계상의 수용체들에의 결함에 있어서 경쟁적이라는 것을 알았다. 이 결과는 긴세노시드 $Rb_{2}$가 세포의 D-1 도파민 수용체에 특이하게 결합한다는 것을 말해 준다.

• The Korean Journal of Physiology and Pharmacology
• /
• v.5 no.1
• /
• pp.93-98
• /
• 2001

The precise mechanism of set-point regulation in hypothalamus was not elucidated. Nitric oxide synthases(NOS) were detected in hypothalamus, however, the roles of NO in hypothalamus was not fully studied. So, we tested the effects of NO on body temperature because preoptic-anterior hypothalamus was known as the presumptive primary fever-producing site. NO donor sodium nitroprusside (SNP, 4 nmol, i.c.v.) elicited marked febrile response, and this febrile response was completely blocked by indomethacin (a cyclooxygenase inhibitor). But, ODQ (selective guanylate cyclase inhibitor, $50\;{\mu}g,$ i.c.v.) did not inhibit fever induced by SNP. The cyclic GMP analogue dibutyryl-cGMP $(100\;{\mu}g,\;i.c.v.)$ induced significant pyreses, which is blocked by indomethacin. $N^G-nitro-L-arginine$ methyl ester (L-NAME, non selective NOS inhibitor) inhibited fever induced by $interleukin-1{\beta}\;(IL-1{\bata},\;10\;ng,\;i.c.v.),$ one of endogenous pyrogens. These results indicate that NO may have an important role, not related to stimulation of soluble guanylate cyclase, in the signal pathway of thermoregulation in hypothalamus.

• The Korean Journal of Physiology and Pharmacology
• /
• v.16 no.3
• /
• pp.211-217
• /
• 2012

Recent studies have demonstrated that nitric oxide (NO) activates transient receptor potential vanilloid subtype 1 (TRPV1) via S-nitrosylation of the channel protein. NO also modulates various cellular functions via activation of the soluble guanylyl cyclase (sGC)/protein kinase G (PKG) pathway and the direct modification of proteins. Thus, in the present study, we investigated whether NO could indirectly modulate the activity of TRPV1 via a cGMP/PKG-dependent pathway in cultured rat dorsal root ganglion (DRG) neurons. NO donors, sodium nitroprusside (SNP) and S-nitro-N-acetylpenicillamine (SNAP), decreased capsaicin-evoked currents ($I_{cap}$). NO scavengers, hemoglobin and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO), prevented the inhibitory effect of SNP on $I_{cap}$. Membrane-permeable cGMP analogs, 8-bromoguanosine 3', 5'-cyclic monophosphate (8bromo-cGMP) and 8-(4chlorophenylthio)-guanosine 3',5'-cyclic monophosphate (8-pCPT-cGMP), and the guanylyl cyclase stimulator YC-1 mimicked the effect of SNP on $I_{cap}$. The PKG inhibitor KT5823 prevented the inhibition of $I_{cap}$ by SNP. These results suggest that NO can downregulate the function of TRPV1 through activation of the cGMP/PKG pathway in peripheral sensory neurons.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.6
• /
• pp.1538-1542
• /
• 2006

The study was designed to investigate the effects of MokhwyangJoki-san Extract (MJSE) on the change of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats, and further to determine the mechanism of MJSE. The results in normal rats were as follows ; MJSE significantly increased rCBF in a dose-dependent manner, and MABP did not change in a dose-dependent manner. This results were suggested that MJSE significantly increased rCBF by dilating pial arterial diameter. The MJSE-induced increase in rCBF was significantly inhibited by pretreatment with methylene blue (10 ${\mu}g/kg$, i.p.), an inhibitor of guanylate cyclase, and was not changed by indomethacin (1 ${\mu}g/kg$, i.p.), an inhibitro of cyclooxygenase. The MJSE-was not changed MABP was decreased by pretreatment with indomethacin but was not changed by methylene blue. This results were suggested that the mechanism of MJSE was mediated by guanylate cyclase.

• The Korean Journal of Zoology
• /
• v.30 no.2
• /
• pp.117-139
• /
• 1987

The present experiments were carried out to investigate the mode of cAMP regulation of cumulus expansion in pig. Intracellular level of cAMP in the cumulus cells was modulated by culturing porcine cumulus oocyte complexes (COC's) with forskolin, an adenylate cyclase stimulator and 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor. The role of calcium in the hormone induced cumulus expansion process was also studied. Forskolin in the medium stimulated cumulus expansion from the concentration of 0.01 $\mu$M and induced full expansion at l-10 $\mu$M In contrast, IBMX in the medium (20-180 $\mu$M) failed to induce the expansion. Verapamil, a calcium ion transport blocker, suppressed follicle stimulating hormone(FSH)-induced cumulus expansion in a dose dependent fashion (0.002-0. 2 mM) when the COC's were exposed to the drugs during culture period (32 hr). But verapamil did not interfere with the triggering action of FSH during early four hours of culture period. The data presented here showed that adenylate cyclase in the porcine cumulus cells may play a key role in the regulation of the intracellular cAMP level and calcium ion may be involved in the later period of cumulus expansion process.

• The Korean Journal of Physiology and Pharmacology
• /
• v.25 no.3
• /
• pp.227-237
• /
• 2021

Carbon monoxide (CO) is a cardioprotectant and potential cardiovascular therapeutic agent. Human cardiac fibroblasts (HCFs) are important determinants of myocardial structure and function. Large-conductance Ca2+-activated K+ (BK) channel is a potential therapeutic target for cardiovascular disease. We investigated whether CO modulates BK channels and the signaling pathways in HCFs using whole-cell mode patch-clamp recordings. CO-releasing molecules (CORMs; CORM-2 and CORM-3) significantly increased the amplitudes of BK currents (IBK). The CO-induced stimulating effects on IBK were blocked by pre-treatment with specific nitric oxide synthase (NOS) blockers (L-NG-monomethyl arginine citrate and L-NG-nitroarginine methyl ester). 8-bromo-cyclic GMP increased IBK. KT5823 (inhibits PKG) or ODQ (inhibits soluble guanylate cyclase) blocked the CO-stimulating effect on IBK. Moreover, 8-bromo-cyclic AMP also increased IBK, and pre-treatment with KT5720 (inhibits PKA) or SQ22536 (inhibits adenylate cyclase) blocked the CO effect. Pre-treatment with N-ethylmaleimide (a thiol-alkylating reagent) also blocked the CO effect on IBK, and DL-dithiothreitol (a reducing agent) reversed the CO effect. These data suggest that CO activates IBK through NO via the NOS and through the PKG, PKA, and S-nitrosylation pathways.

• Journal of dental hygiene science
• /
• v.6 no.1
• /
• pp.1-9
• /
• 2006

Cathepsin K (cat K) is the major cysteine protease expressed in osteoclasts and was thought to play a key role in matrix degradation during bone resorption. It was shown that the intracellular maturation of cat K was prevented by the cAMP antagonist, Rp-cAMP, and the protein kinase A (PKA) inhibitors of KT5720 and H89. In contrast, forskolin, a adenylate cyclase agonist, rather induced Cat K processing and maturation in osteoclasts. Furthermore, to determine whether cat K processing and maturation signaling involves protein kinase C (PKC), mouse total bone cells were treated with calphostin C, a specific inhibitor of PKC, however, no effect was observed, indicating that calphostin C did not affect to osteoclast-mediated cat K processing and maturation. Thus, it is indicated that the cAMP-PKA signaling pathway regulates cat K maturation in osteoclasts. Since secreted proenzymes have the potential to reenter the cell via M6P receptor, to prevent this possibility, it was tested cAMP antagonist Rp-cAMP and the PKA inhibitors KT5720 and H89 in the absence or presence of M6P. Inhibition of cat K processing by Rp-cAMP, KT5720, or H89 was observed in a dose-dependent manner. Furthermore, the addition of M6P resulted in enhanced potency of Rp-cAMP, KT5720 and H89. These dose-dependently inhibited in vitro bone resorption with a potency similar to that observed for inhibition of cat K processing.

• Journal of dental hygiene science
• /
• v.2 no.1
• /
• pp.47-51
• /
• 2002

The concentration of intracellular $Ca^{2+}$ was measured by spectrofluorometer after rat submandibular acinar cells were loaded with fura-2/AM(fura-2). After isoproterenol and octanol were administered while letting submandibular gland acinar cell placed in a perfusion chamber flow through a standard solution, the changes of $Ca^{2+}$ concentration were measured. When they were administered separately, there showed little changes of intracellular $Ca^{2+}$ concentration. When they were administered at the same time, however the concentration of intracellar $Ca^{2+}$ was shown to increase. When forskolin, an adenylate cyclase activater, was administerd together with octanol the response looked similar to the response of isoproterenol. In case of the extracellular $Ca^{2+}$ was removed by omitting $Ca^{2+}$ in standard solution and treating EGTA, isoproterenol and forskolin does not affect to the concentration of intracellular $Ca^{2+}$. Therefore, it was certified that the increase of intracellular $Ca^{2+}$ was caused from outside the cell. In order to know that the $Ca^{2+}$ influx is related with capacitative entry pathway, godolinium, blocker of that pathway was treated. With the result of that experiment there was no complete control of the increase in the concentration of intracellular $Ca^{2+}$. However, speed and amount of $Ca^{2+}$ increase was comparatively diminished.