• Molecules and Cells
• /
• 제37권10호
• /
• pp.747-752
• /
• 2014

Protein kinase C (PKC) family members phosphorylate a wide variety of protein targets and are known to be involved in diverse cellular signaling pathways. However, the role of PKC in receptor activator of NF-${\kappa}B$ ligand (RANKL) signaling has remained elusive. We now demonstrate that $PKC{\beta}$ acts as a positive regulator which inactivates glycogen synthase kinase-$3{\beta}$ (GSK-$3{\beta}$) and promotes NFATc1 induction during RANKL-induced osteoclastogenesis. Among PKCs, $PKC{\beta}$ expression is increased by RANKL. Pharmacological inhibition of $PKC{\beta}$ decreased the formation of osteoclasts which was caused by the inhibition of NFATc1 induction. Importantly, the phosphorylation of GSK-$3{\beta}$ was decreased by $PKC{\beta}$ inhibition. Likewise, down-regulation of $PKC{\beta}$ by RNA interference suppressed osteoclast differentiation, NFATc1 induction, and GSK-$3{\beta}$ phosphorylation. The administration of PKC inhibitor to the RANKL-injected mouse calvaria efficiently protected RANKL-induced bone destruction. Thus, the $PKC{\beta}$ pathway, leading to GSK-$3{\beta}$ inactivation and NFATc1 induction, has a key role in the differentiation of osteoclasts. Our results also provide a further rationale for $PKC{\beta}$'s therapeutic targeting to treat inflammation-related bone diseases.

• 한국항행학회논문지
• /
• 제16권6호
• /
• pp.935-943
• /
• 2012

본 논문에서는 위성항법기반 교통인프라 기술개발의 네트워크 수신국 사이트 선정을 위하여 사전 조사, 현장 조사, 현장 환경 분석의 3단계 선정 절차를 제시하였으며 실제 테스트베드인 오창 지역을 기준으로 4개의 후보지를 도출하였다. IGS, NGS 등과 같은 국제상시관측기관이 제안하는 사이트 선정 권고안을 정리하여 위성항법기반 교통인프라 기술개발에 적합한 요구사항을 도출하고 이를 만족하는 1차 후보군을 선정하는 작업이 사전조사이며, 1차 후보군에 대한 육안 가시검사 및 환경, 기타 조사를 통하여 2차 후보군을 선정하는 작업이 현장조사이다. 또한 선정된 2차 후보군에 대해 상공장애도 분석과 전파환경 분석을 통해 최종적으로 수신국 사이트 후보지를 선정하는 것이 현장 환경 분석이다. 위와 같은 일련의 선정 절차를 통해 1차 16개 후보군, 2차 7개 후보군, 3차 최종 4개의 수신국 사이트를 효과적으로 선정할 수 있었다.

• 한국환경농학회지
• /
• 제34권2호
• /
• pp.111-119
• /
• 2015

BACKGROUND: Ethychlozate (ECZ) is a plant growth regulator of synthetic auxin for agricultural commodities (ACs). Accurate and sensitive method to determine ECZ in diverse ACs on global official purpose is required to legal residue regulation. As the current official method is confined to the limited type of crops with poor validation, this study was conducted to improve and extend the ECZ method using high-performance liquid chromatography (HPLC) in all the registered crops with method verification. METHODS AND RESULTS: ECZ and its acidic metabolite (ECZA) were both extracted from acidified samples with acetone and briefly purified by dichloromethane partition. ECZ was hydrolyzed to form ECZA and the combined ECZA was finally purified by ion-associated partition including hexane-washing. The instrumental quantitation was performed using HPLC/ FLD under ion-suppression of ECZA with no interference by sample co-extractives. The average recoveries of intra- and inter-day experiment ranged from 82.0 to 105.2% and 81.7 to 102.8%, respectively. The repeatability and reproducibility for intra- and inter-day measurements expressed as a relative standard deviation was less than 8.7% and 7.4%, respectively. CONCLUSION: Established analytical method for ECZ residue in ACs was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권9호
• /
• pp.4363-4368
• /
• 2012

The epidermal differentiation complex (EDC) contains a large number of gene products which are crucial for the maturation of the human epidermis and can contribute to skin diseases, even carcinogenesis. It is generally accepted that activation of oncogenes and/or inactivation of tumor suppressor genes play pivotal roles in the process of carcinogenesis. Here, NICE-3, a novel EDC gene, was found to be up-regulated in human hepatocellular carcinoma (HCC) by quantitative real-time RT-PCR. Furthermore, overexpression of exogenous NICE-3 by recombinant plasmids could significantly promote cell proliferation, colony formation and soft agar colony formation in Focus and WRL-68 HCC cell lines. Reversely, NICE-3 silencing by RNA interference could markedly inhibit these malignant phenotypes in YY-8103 and MHCC-97H cells. Moreover, cell cycle analysis of MHCC-97H transfected with siRNA by flow cytometry showed that NICE-3 knockdown may inhibit cell growth via arrest in G0/G1 phase and hindering entry of cells into S phase. All data of our findings indicate that NICE-3 may contribute to human hepatocellular carcinoma by promoting cell proliferation.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
• /
• pp.81.2-82
• /
• 2003

Plants have evolved along with pathogens, and they have developed sophisticated defense systems against specific microorganisms to survive. G-protons are considered one of the upstream signaling components working as a key for the defense signal transduction pathway. For activation and inactivation of G-protein, GTP-biding proteins are involved. GTP -binding proteins are found in all organisms. Small GTP-binding proteins, having masses of 21 to 30kD, belong to a superfamily, often named the Ras supefamily because the founding members are encoded by human Ras genes initially discovered as cellular homologs of the viral ras oncogene. Members of this supefamily share several common structural features, including several guanine nucleotide binding domains and an effector binding domain. However, exhibiting a remarkable diversity in both structure and function. They are important molecular switches that cycle between the GDP-bound inactive form into the GTP-bound active form through GDP/GTP replacement. In addition, most GTP-binding proteins cycle between membrane-bound and cytosolic forms. such as the RAC family are cytosolic signal transduction proteins that often are involved in processing of extracellular stimuli. Plant RAC proteins are implicated in regulation of plant cell architecture secondary wall formation, meristem signaling, and defense against pathogens. But their molecular mechanisms and functions are not well known. We isolated a RacB homolog from rice to study its role of defense against pathogens. We introduced the constitutively active and the dominant negative forms of the GTP-hinging protein OsRacB into the wild type rice. The dominant negative foms are using two forms (full-sequence and specific RNA interference with RacB). Employing southern, and protein analysis, we examine to different things between the wild type and the transformed plant. And analyzing biolistic bombardment of onion epidermal cell with GFP-RacB fusion protein revealed association with the nucle.

• The Plant Pathology Journal
• /
• 제26권1호
• /
• pp.8-16
• /
• 2010

The phytopathogenic fungus Magnaporthe oryzae is a major limiting factor in rice production. To understand the genetic basis of M. oryzae pathogenic development, we previously analyzed a library of T-DNA insertional mutants of M. oryzae, and identified ATMT0879A1 as one of the pathogenicity-defective mutants. Molecular analyses and database searches revealed that a single TDNA insertion in ATMT0879A1 resulted in functional interference with an annotated gene, MGG00056, which encodes a short-chain dehydrogenase/reductase (SDR). The mutant and annotated gene were designated as $MoSDR1^{T-DNA}$ and MoSDR1, respectively. Like other SDR family members, MoSDR1 possesses both a cofactor-binding motif and a catalytic site. The expression pattern of MoSDR1 suggests that the gene is associated with pathogenicity and plays an important role in M. oryzae development. To understand the roles of MoSDR1, the deletion mutant ${\Delta}Mosdr1$ for the gene was obtained via homology-dependent gene replacement. As expected, ${\Delta}Mosdr1$ was nonpathogenic; moreover, the mutant displayed pleiotropic defects in conidiation, conidial germination, appressorium formation, penetration, and growth inside host tissues. These results suggest that MoSDR1 functions as a key metabolic enzyme in the regulation of development and pathogenicity in M. oryzae.

• BMB Reports
• /
• 제45권6호
• /
• pp.331-336
• /
• 2012

The retinoid-related orphan nuclear receptor gamma ($ROR{\gamma}$) plays critical roles in regulation of development, immunity and metabolism. As transcription factor usually forms a protein complex to function, thus capturing and dissecting of the $ROR{\gamma}$ protein complex will be helpful for exploring the mechanisms underlying those functions. After construction of the recombinant tandem affinity purification (TAP) plasmid, pMSCVpuro $ROR{\gamma}$-CTAP(SG), the nuclear localization of $ROR{\gamma}$-CTAP(SG) fusion protein was verified. Following isolation of $ROR{\gamma}$ protein complex by TAP strategy, seven candidate interacting proteins were identified. Finally, the heat shock protein 90 (HSP90) and receptor-interacting protein 140 (RIP140) were confirmed to interplay with $ROR{\gamma}$ by co-immunoprecipitation. Interference of HSP90 or/and RIP140 genes resulted in dramatically decreased expression of CYP2C8 gene, the $ROR{\gamma}$ target gene. Data from this study demonstrate that HSP90 and RIP140 proteins interact with $ROR{\gamma}$ protein in a complex format and function as co-activators in the $ROR{\gamma}$-mediated regulatory processes of HepG2 cells.

• 전기학회논문지P
• /
• 제51권3호
• /
• pp.120-125
• /
• 2002

The switching-mode power converter has been widely used because of its features of high efficiency and small weight and size. These features are brought by the ON-OFF operation of semiconductor switching devices. However, this switching operation causes the surge and EMI(Electromagnetic Interference) which deteriorate the reliability of the converter themselves and entire electronic systems. This problem on the surge and noise is one of the most serious difficulties in AC-to-DC converter. In the switching-mode power converter, the output voltage is generally controlled by varying the duty ratio of main switch. When a converter operates in steady state, duty ratio of the converter is kept constant. So the power of switching noise is concentrated in specific frequencies. Generally, to reduce the EMI and improve the immunity of converter system, the switching frequency of converter needs to be properly modulated during a rectified line period instead of being kept constant. Random Pulse Width Modulation (RPWM) is performed by adding a random perturbation to switching instant while output-voltage regulation of converter is performed. RPWM method for reducing conducted EMI in single switch three phase discontinuous conduction mode boost converter is presented. The more white noise is injected, the more conducted EMI is reduced. But output-voltage is not sufficiently regulated. This is the reason why carrier frequency selection topology is proposed. In the case of carrier frequency selection, output-voltage of steady state and transient state is fully regulated. A RPWM control method was proposed in order to smooth the switching noise spectrum and reduce it's level. Experimental results are verified by converter operating at 300V/1kW with 5%~30% white noise input. Spectrum analysis is performed on the Phase current and the CM noise voltage. The former is measured with Current Probe and the latter is achieved with LISN, which are connected to the spectrum analyzer respectively.

• 한국전자통신학회논문지
• /
• 제11권5호
• /
• pp.441-450
• /
• 2016

국제전기통신연합(ITU) 전파규칙(Radio Regulation)에서는 인공적인 유도 없이 공간에 퍼져나가는 3000GHz이하의 주파수를 전자파라고 정의하고 있으며, 우리나라도 국제 정의를 따르고 있다. 전파는 인공적인 유도 없이 공간에 퍼져 나가는 전자파로서 ITU가 정한 범위안의 주파수를 가진 것을 말한다. 이중 업무를 분배한 주파수는 300GHz까지인데, 분배된 주파수 중에서도 우리가 매일 접하는 생활용 주파수 대역의 90% 이상이 3GHz 이하이다. 전파는 송신설비 만 갖추면 누구나 생성해 낼 수 있는 것으로 고갈 없이 무한정 발생할 수 있지만, 주파수의 전파를 동일한 시간과 공간에서 이용하게 되면 혼간섭이 발생하게 되어 전파자원을 이용할 수 없게 된다. 이러한 이용 상의 물리적 유한성으로 인해 우리나라에서는 1961년 처음으로 전파관리법을 제정하여 전파자원을 국가가 관리하도록 하고, 권리를 부여받은 경우에만 전파를 이용할 수 있도록 규율하고 있다.

• Molecules and Cells
• /
• 제37권12호
• /
• pp.907-911
• /
• 2014

The function of reactive oxygen species (ROS) as second messengers in cell differentiation has been demonstrated only for a limited number of cell types. Here, we used a well-established protocol for BMP2-induced neuronal differentiation of neural crest stem cells (NCSCs) to examine the function of BMP2-induced ROS during the process. We first show that BMP2 indeed induces ROS generation in NCSCs and that blocking ROS generation by pretreatment of cells with diphenyleneiodonium (DPI) as NADPH oxidase (Nox) inhibitor inhibits neuronal differentiation. Among the ROS-generating Nox isozymes, only Nox4 was expressed at a detectable level in NCSCs. Nox4 appears to be critical for survival of NCSCs at least in vitro as down-regulation by RNA interference led to apoptotic response from NCSCs. Interestingly, development of neural crest-derived peripheral neural structures in Nox4-/- mouse appears to be grossly normal, although Nox4-/- embryos were born at a sub-Mendelian ratio and showed delayed over-all development. Specifically, cranial and dorsal root ganglia, derived from NCSCs, were clearly present in Nox4-/- embryo at embryonic days (E) 9.5 and 10.5. These results suggest that Nox4-mediated ROS generation likely plays important role in fate determination and differentiation of NCSCs, but other Nox isozymes play redundant function during embryogenesis.