• Bulletin of the Korean Chemical Society
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• 제29권6호
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• pp.1137-1140
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• 2008

M1 RNA, the catalytic subunit of Escherichia coli RNase P, is an essential ribozyme that processes the 5' leader sequence of tRNA precursors (ptRNAs). Using KS2003, an E. coli strain generating only low levels of M1 RNA, which showed growth defects, we examined whether M1 RNA is involved in polycistronic mRNA processing or degradation. Microarray analysis of total RNA from KS2003 revealed six polycistronic operon mRNAs (acpP-fabF, cysDNC, flgAMN, lepAB, phoPQ, and puuCBE) showing large differences in expression between the adjacent genes in the same mRNA transcript compared with the KS2001 wild type strain. Model substrates spanning an adjacent pair of genes for each polycistronic mRNA were tested for RNase P cleavage in vitro. Five model RNAs (cysNC, flgMN, lepAB, phoPQ, and puuBE) were cleaved by RNase P holoenzyme but not by M1 RNA alone. However, the cleavages occurred at non-ptRNA-like cleavage sites, with much less efficiency than the cleavage of ptRNA. Since cleavage products generated by RNase P from a polycistronic mRNA can have different in vivo stabilities, our results suggest that RNase P cleavage may lead to differential expression of each cistron.

• Bulletin of the Korean Chemical Society
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• 제28권6호
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• pp.1010-1014
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• 2007

M1 RNA is the catalytic component of RNase P, a tRNA-processing enzyme in Escherichia coli. M1 RNA is produced in the cell by transcription of the rnpB gene and subsequent processing at the 3' end. The 3' flanking region of rnpB contains repeated sets of overlapping sequences coding for small proteins. The issue of whether these proteins are expressed remains to be established. In this study, we showed the expression of a small protein encoded by the first repeat within the 3' flanking region of rnpB. Interestingly, protein expression was increased at lower temperatures. The termination efficiency of rnpB terminators was decreased at lower temperatures, suggesting that antitermination is responsible for enhanced protein expression. Moreover, the purified small protein contained M1 RNA, implying a role as a specific RNA-binding protein.

• 약학회지
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• 제32권2호
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• pp.137-140
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• 1988

To investigate polyacetylene compounds isolated from petroleum ether extract of panax ginseng effect on the macromolecule synthesis, lympoid lukemia L1210 cell was incubated with them at 4, 8, 12,16 hours. Panaxydol, panaxynol and panaxytriol as cytotoxic substances inhibited the synthesis of macromolecule such as DNA, RNA and protein. Panaxydol which had the most potent cytotoxicity among these three compounds showed the strongest inhibitory effect on DNA, RNA and protein synthesis. For DNA and RNA synthesis, panaxynol and panaxytriol decreased the rate of inhibition with the incubation time but panaxydol had a strongest inhibitory effect at 16 hour incubation time. Protein synthesis was markedly inhibited by all these polyacetylene compounds. It was obserbed that there is a relationship between cytotoxicities of polyacetylene compounds and the inhibition of macromolecule synthesis.

• 대한한방내과학회지
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• 제27권3호
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• pp.653-663
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• 2006

Objective : Graves' disease, the most common cause of hyperthyroidism, is an autoimmune disorder associated with autoantibodies to the TSH receptor. The clinical features of Graves' disease are goiter and hypermetabolic symptoms induced by excessive hormones. Antithyroid drug therapy is the first-line treatment for Graves' disease in Korea, Japan and European countries. Yet in spite of a long period and high-dose of treatment, it is hard to achieve remission because of adverse effects, frequent recurrence and resistance to antithyroid drugs. Recently, it has been reported that the abnormal thyroid hormone and clinical symptoms of Graves' disease were reduced by Ahnjeonbaekho-tang (AJBHT). Methods : To investigate the effectiveness and action mechanism of AJBHT, we studied the influence of AJBHT on FRTL-5 thyroid cell proliferation, DNA synthesis and expression of T4, TSH, cAMP, Tg and TPO mRNA. Results : AJBHT significantly inhibited the FRTL-5 cell proliferation, DNA synthesis, T4 synthesis, cAMP production and the expression of Tg mRNA in comparison with control and MMI. Conclusions : These results suggest that AJBHT may inhibit the cell proliferation and DNA synthesis by regulating the cAMP, and suppress the T4 synthesis by modulating Tg mRNA expression and cAMP synthesis, and that it may be useful agent for treating the goiter and hormone abnormality of Graves' disease.

• The Plant Pathology Journal
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• 제17권3호
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• pp.115-122
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• 2001

Potato virus X (PVX) is a flexuous rod-shaped virus containing a single plus-strand RNA. Viral RNA synthesis is precisely regulated by regulatory viral sequences and by viral and/or host proteins. RNA sequence element as well as stable RNA stem-loop structure in the 5' end of the genome affect accumulation of genomic RNA and subgenomic RNA (sgRNA). The putative sgRNA promoter regions upstream of the PVX triple gene block (TB) and coat protein (CP) gene were critical for both TB and CP sgRNA accumulation. Mutations that disrupted complementarity between a region at the 5' end of the genomic RNA and the sequences located upstream of each sgRNA initiation site is important for PVX RNA accumulation. Compensatory mutations that restore complementarity restored sgRNA accumulation levels. However, the extent of reductions in RNA levels did not directly correlate with the degree of complementarity, suggesting that the sequences of these elements are also important. Gel-retardation assays showed that the 5' end of the positive-strand RNA formed an RNA-protein complex with cellular proteins, suggesting possible involvement of cellular proteins for PVX replication. Future studies on cellular protein binding to the PVX RNA and their role in virus replication will bring a fresh understanding of PVX RNA replication.

• Asian-Australasian Journal of Animal Sciences
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• 제21권5호
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• pp.715-722
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• 2008

There are marked variations in the activity of lipoprotein lipase (LPL) among adipose depots. The aim of this study was to compare the mechanisms of 24 h of fasting on LPL regulation between epididymal (EPI) adipocytes and mesenteric (MES) adipocytes in rats. 1-Day fasting consistently decreased activities of heparin-releasable LPL, total extractable LPL and cellular LPL markedly in both EPI and MES fat pads. LPL activity in MES fat pads was relatively lower than in the EPI fat pads. Consistent with data on LPL activity, the levels of expression of LPL mRNA in both nutritional states were lower in MES than EPI adipose tissue and isolated adipocytes. The decreased LPL activity after 1 day of fasting in MES adipocytes was explained mainly by a 50% decrease in the relative abundance of LPL mRNA level and a parallel 50% decrease in relative rate of LPL synthesis. In contrast, fasting of 1 day in EPI adipocytes decreased total LPL activity by 47% but did not affect LPL mRNA level or relative rate of LPL synthesis. A decrease in overall protein synthesis contributed to the decreased LPL activity after 1 day fasting both in EPI and MES adipocytes. In MES adipocytes the decrease in LPL activity, LPL mRNA and LPL synthesis were comparable, but in EPI adipocytes the changes in LPL activity were substantially larger than the changes in LPL mRNA level and LPL synthesis. Therefore, fasting decreased fat cell size, LPL activity, LPL mRNA level and relative rate of LPL synthesis in rats, and these effects were more marked in the MES adipocytes. These results clearly demonstrate the regional variations in the metabolic response of adipose tissue and LPL functions to fasting.

• 한국동물학회지
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• 제23권3호
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• pp.149-160
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• 1980

생쥐 초기발생배에서 일어나는 단백질 합성양상에 미치는 환경성 돌연변이원인 MMS와 captan의 효과를 2차원 전기영동법과 fluorography를 이용하여 연구하였다. 착상이전까지 크게 나누어 세종류의 단백질이 합성되고 있음이 관찰되었다. 즉, 첫번째 종류는 난자형성기간동안에 합성, 축적되었다가 수정과 동시에 활성화된 m-RNA에 의하여 합성되는 단백질 종류이다. 이러한 단백질들은 거의 MMS에 의하여 영향을 받지 않은 것으로 보였다. 둘째번 종류로서는 새로 전사된 m-RNA에 의하여 합성된 시기에 따른 특유의 것들로서 MMS에 의해서 선택적으로 그 합성이 억제되는 단백질들이다. 세번째 종류로서는 수명이 끝난 m-RNA를 반복적으로 전사함으로서 합성되며, MMS에 의하여 억제되는 단백질들이다. 이와같이 MMS는 새로 전사된 m-RNA에 의한 거의 모든 단백질 합성을 억제하는 반면에, MMS로 처리되지 않은 정상적인 발생배에서는 관찰할 수 없는 새로운 단백질의 합성을 촉진하는 경우가 있었다. Captan은 생쥐 상실배의 단백질합성에 영향을 주지 못하였다.

• Journal of Microbiology and Biotechnology
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• 제16권3호
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• pp.355-359
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• 2006

The functional stability of mRNA is one of the crucial factors affecting the efficiency of in vitro translation. As the rapid degradation of mRNA in the cell extract (S30 extract) causes early termination of the translational reactions, extending the mRNA half-life will improve the productivity of the in vitro protein synthesis. Thus, a simple PCR-based method is introduced to increase the stability of mRNA in an S30 extract. The target genes are PCR-amplified with primers designed to make the ends of the transcribed mRNA molecule anneal to each other. When compared with normal mRNA, the mRNA with the annealing sequences resulted in an approximately 2-fold increase of protein synthesis in an in vitro translation reaction. In addition, sequential transcription and translation reactions in a single tube enabled direct protein expression from the PCR-amplified genes without any separate purification of the mRNA.

• Journal of Microbiology
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• 제45권5호
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• pp.418-421
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• 2007

The nucleotide at position 791(G791) of E. coli 16S rRNA was previously identified as an invariant residue for ribosomal function. In order to characterize the functional role of G791, base substitutions were introduced at this position, and mutant ribosomes were analyzed with regard to their protein synthesis ability, via the use of a specialized ribosome system. These ribosomal RNA mutations attenuated the ability of ribosomes to conduct protein synthesis by more than 65%. A transition mutation (G to A) exerted a moderate effect on ribosomal function, whereas a transversion mutation (G to C or U) resulted in a loss of protein synthesis ability of more than 90%. The sucrose gradient profiles of ribosomes and primer extension analysis showed that the loss of protein-synthesis ability of mutant ribosomes harboring a base substitution from G to U at position 791 stems partially from its inability to form 70S ribosomes. These findings show the involvement of the nucleotide at position 791 in the association of ribosomal subunits and protein synthesis steps after 70S formation, as well as the possibility of using 16S rRNA mutated at position 791 for the selection of second-site revertants in order to identify ligands that interact with G791 in protein synthesis.

• 대한화장품학회지
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• 제23권3호
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• pp.9-23
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• 1997

Retinoids are essential regulators of spithelial cell growth and celluar differentiation. They are also known to be effective in photoaging. It was reported that topical application of retinoic acid improves facial wrinkle carsed by collagen synthesis reduction in photodamaged skin. Collagen synthesis by retinoic acid may contribute to the wrinkle effacement. Since celluar retinoic acid binding protein II is slsctively induced in human skin and dermal fibroblasts in vitro by retinoic acid, this response can be used to mesure retinoids potency and activity. In order to know the activity of retinoids and their relations with collagen synthesis, we treated dermal fibroblasts with retinoids for 48 hours at 10-6-10-7M and measured CRABPII mRNA level by quantitative Nortern blotting. We also measured the rate of collagen systhesis by retinoids using 3-dimensional dermal equivalent. CRABPII mRNA level was increased 3-fold by retinoic acid, 2.1-fold by retinol and 1.4-fold by retinaldehyde. Collagen systhesis was increased 34% by all-trans retinioc acid, 26% by retinol, 17% by retinaldehyde and 7% by retinyl palmitate. From the above results, retinoids were found to be a potent indecers of CRABPII mRNA and collagen synthesis. Though retinoic acid was the most effective, its use has been restricted because of the side effects. Instead, retinol can be a best candidate in cosmetics for the treatment of photodamaged skin in terms of efficacy and safety.