• 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 and Biotechnology
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• 제16권10호
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• pp.1646-1649
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• 2006

Protein synthesis is the ultimate outcome of gene expression which, in turn, is regulated by several translation factors. We attempted to identify substances that can inhibit the translation process in vitro when the outcome protein is luciferase. To this end, we developed a sensitive cell-free protein synthesis assay using luciferase as the reporter. The synthesis of luciferase increased proportionately as mRNA was added to a $15-{\mu}l$reaction medium in concentrations raging from 5 ng to 500 ng. The maximum amount of luciferase was synthesized when the media were incubated at $25^{\circ}C$ for 40 min. The concentration of each compound that inhibited luciferase production by 50% ($IC_{50}$) was calculated. Hygromycin, puromycin, and cycloheximide yielded an $IC_{50}$ of 0.008, 0.8, and $0.7{\mu}g/ml$, respectively. A filtrate of Streptomyces spp. isolates inhibited protein synthesis up to S-fold when added to the in vitro translation assay mixture.

• Journal of Microbiology and Biotechnology
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• 제1권4호
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• pp.232-239
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• 1991

Caboxymethyl cellulase (CMCase) I was purified from the induced culture filtrate of Penicllium verruculosum F-3 by ammonium sulfate precipitation, DEAE-Sephadex A-50 chromatography and Bio-gel P-150 filtration. The purified enzyme was assumed to be a glycoprotein consisting of 8.5% carbohydrate and having a molecular weight of 70.000 in SDS-polycrylamide gel electrophoresis (SDS-PAGE). The purified enzyme-specific anti-CMCase I IgG was obtained by rabbit immunization and protein A-sepharose CL-4B chromatography. The fungal poly($A^+$) RNA was isolated from the total RNA of the mycelium grown under cellulase induction conditions by oligo(dT)-cellulosse chromatography. The translation products in vitro were prepared by translating the isolated poly ($A^+$) RNA in rabbit reticulocyte lysate and analyzed by SDS-PAGE and fluorography. Of the translation products, CMCase I was identified by the immunoprecipitation against anti-CMCase I IgG.

• 한국미생물·생명공학회지
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• 제35권1호
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• pp.36-40
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• 2007

Redox signaling은 단백질을 산화환원 시키는 세포의 중요 신호가 전달되어, 그 단백질의 기능이 변화함으로써 세포의 성장 및 사멸을 조절하게 되는 과정이다. 단백질 합성 구성원의 산화, 환원 과정에 의한 단백질 합성 조절을 알아보기 위해 환원제인 DTT 존재 하에 단백질 합성 활성을 관찰한 결과 DTT가 존재하지 않는 것에 비해 단백질합성이 1.4배 정도 증가됨이 관찰되어 redox potential을 보이는 것으로 보아 환원제가 단백질 합성을 좀 더 증진시키는 것으로 사료된다. DTT에 의한 이러한 현상은 산화환원 조절 단백질인 thioredoxin를 첨가한다면 thiol기에 환원력이 전달되어 단백질합성이 더욱 촉진되기 때문에 효모에서 thioredoxin유전자를 cloning하고 이로부터 효모에서 GST-thioredoxin을 분리하였다. DTT 존재 하에 산화환원 조절 단백질인 thioredoxin을 농도별로 첨가하였을 때의 단백질 합성이 어떻게 조절되는지 알아보았다. 반응 액에 DTT를 넣은 것과 넣지 않은 것을 사용하여 thioredoxin을 0ng, 18ng, 90ng, 460ng, 2,300 ng의 농도로 각각 넣어서 반응시켜 보았다. 이렇게 반응시킨 반응물에서 만들어진 단백질 활성을 측정하였는데 thioredoxin의 농도가 높아질수록 그 활성이 높게 나타났으며, thioredoxin을 넣은 것이 넣지 않은 것에 비해 활성이 약 4배 이상 높게 나왔다 이 결과는 산화환원 조절 단백질인 thioredoxin이 환원력을 단백질합성구성원에 효율적으로 전달하는데 관여함을 보여주는 것이며, 산화환원이 단백질 합성 시 중요한 신호전달 과정임을 암시한다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.258-261
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• 2006

The addition of zeolite particles enhances the stability of mRNA molecules in a cell-free protein synthesis system. When $20{\mu}g/{\mu}L$ of zeolite (Y5.4) is added to a reaction mixture of cell-free protein synthesis, a substantial increase in protein synthesis is observed. The stabilizing effect of zeolite is most dearly observed in an in vitro translation reaction directed by purified mRNA, as opposed to a coupled transcription and translation reaction. Upon the addition of zeolite in the in vitro translation reaction, the life span of the mRNA molecules is substantially extended, leading to an 80% increase in protein synthesis. The effect of zeolite upon the mRNA stability appears be strongly related to the cation exchange (potassium to sodium) reaction. Our results demonstrate the possibility of modifying this biological process using heterogeneous, non-biological substances in a cell-free protein synthesis system.

• 생명과학회지
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• 제15권5호
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• pp.779-782
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• 2005

Coupled transcription/translation cocktail을 이용하여 R. glutinis EH 유전자를 in vitro에서 합성하고 활성을 평가하였다. SDS-PAGE 및 immunoblotting을 통하여 45 kDa 크기의 EH 단백질이 발현되었음을 확인하였고, NBP assay 및 chiral GC 분석을 통해 발현된 단백질이 (R)-styrene oxide에 대한 입체선택성이 있음을 확인하였다. 따라서 무세포 단백질 합성 시스템을 이용하여 입체선택성을 유지시킨 EH 유전자 발현이 가능하며, 이러한 방법은 putative EH 유전자 탐색 등에 효율적으로 응용될 것이다.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2002년도 국제심포지엄
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• pp.117-117
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• 2002

The oocytes from most of animal species accumulate genetic information and other necessary materials during oogenesis for the later use in the early development. Over the years oocyte maturation has been studied extensively both in vitro and in vivo. Particularly, maturation of follicular oocyte in vitro becomes one of the important tools for the studies of basic cell biology, the in vitro technology of animal production, and in particular, the somatic cell cloning by nuclear transfer. We examined meiotic maturation and cumulus expansion in the presence of translation or transcription inhibitors for varying periods of in viかo maturation (IVM) of pig oocyte. In Experiment 1, the results revealed that translation and transcription inhibitors inhibited cumulus expansion and meiotic maturation during 35h of IVM. However, 50 to 60% of the oocytes underwent nuclear maturation without cumulus expansion during 75h of IVM. The rest of the oocytes were arrested at metaphase I (40-50%) in the presence of the inhibitors. In Experiment II, the OCCs were exposed to the drugs only for 15h to examine translation and transcription inhibitors on cumulus expansion and meiotic maturation. Transcription inhibitors for 15h did not arrest meiotic maturation when the oocytes were cultured for subsequent, necessary period of IVM, whereas cumulus expansion was completely inhibited, suggesting that initial 15h is critical transcription activity far cumulus expansion. Translation inhibitors for 15h exposure did not alter cumulus expansion and meiotic maturation during subsequent culture in the absence of the drugs. In Experiment III, the OCCs were exposed to the drugs only for later 30h to examine the influence of transcription and translation inhibitors on oocyte maturation. Interestingly, all meiotic maturation underwent normally with full expansion of cumulus. Similar results were obtained from Experiment IV where 5h of exposure from 15 to 20h of IVM culture to the drugs was performed and subsequently cultured for same period in fresh medium. Taken there results together, both transcription and translation are necessary for nuclear maturation and cumulus expansion, and first 15h IVM for cumulus expansion is critical. The arrested oocytes by the drugs were still capable of undergoing nuclear maturation, although cumulus expansion was affected.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
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• pp.57-62
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• 1999

Light-regulated translation of chloroplast mRNAs requires nuclear-encoded trans-acting factors that interact with the 5' untranslated region (UTR) of these mRNAs. A set of four proteins (60, 55, 47, and 38 kDa) that bind to the 5'-UTR of the psbA mRNA had been identified in C. reinhardtii. 47 kDa protein (RB47) was found to encode a chloroplast poly (A)-binding protein (cPABP) that specifically binds to the 5'-UTR of the psbA mRNA, and essential for translation of this mRNA, cDNA encoding 60 kDa protein (RB60) was isolated, and the amino acid sequence of the encoded protein was highly homologous to plants and mammalian protein disulfide isomerases (PDI), normally found in the endoplasmic reticulum (ER). Immunoblot analysis of C. reinhardtii proteins showed that anti-PDI recognized a distinct protein of 56 kDa in whole cell extract, whereas anti-rRB60 detected a 60 kDa protein. The ER-PDI was not retained on heparin-agarose resin whereas RB60 was retained. In vitro translation products of the RB60 cDNA can be transported into C. reinhardtii chloroplast in vitro. Immunoblot analysis of isolated pea chloroplasts indicated that higher plant also possess a RB60 homolog. In vitro RNA-binding studies showed that RB60 modulates the binding of cPABP to the 5'-UTR of the psbA mRNA by reversibly changing the redox status of cPABP using redox potential or ADP-dependent phosphorylation. Site-directed mutagenesis of -CGHC- catalytic site in thioredoxin-like domain of RB60 is an unique PDI located in the chloroplast of C. reinhardtii, and suggest that the chloroplast PDI may have evolved to utilize the redox-regulated thioredoxin like domain as a mechanism for regulating the light-activated translation of the psbA mRNA.

• The Plant Pathology Journal
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• 제28권2호
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• pp.197-201
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• 2012

Potyviruses express their RNA genomes through the production of polyproteins that are processed in host cells by three virus-encoded proteases. Soybean plants produce large amounts of protease inhibitors during seed development and in response to wounding that could affect the activities of these proteases. The in vitro activities of two of the proteases of Soybean mosaic virus (SMV) and Tobacco vein mottling virus (TVMV) were compared in the rabbit reticulocyte lysate in vitro translation system using synthetic RNA transcripts. Transcripts produced from SMV and TVMV cDNAs that included the P1 and helper component-protease (HC-Pro) coding regions directed synthesis of protein products that were only partially processed. Unprocessed poly-proteins were not detected from transcripts that included all of the P1, HC-Pro, P3 and portions of the cylindrical inclusion protein coding regions of either virus. Addition of soybean trypsin inhibitor to in vitro translation reactions increased the accumulation of the unprocessed polyprotein from TVMV transcripts, but did not alter the patterns of proteins produced from SMV. These experiments suggest that SMV-and TVMV-encoded proteases are differentially sensitive to protease inhibitors.

• Journal of Microbiology and Biotechnology
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• 제34권6호
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• pp.1348-1355
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• 2024

The eukaryotic translation initiation factor eIF5B is a bacterial IF2 ortholog that plays an important role in ribosome joining and stabilization of the initiator tRNA on the AUG start codon during the initiation of translation. We identified the fluorophenyl oxazole derivative 2,2-dibromo-1-(2-(4-fluorophenyl)benzo[d]oxazol-5-yl)ethanone quinolinol as an inhibitor of fungal protein synthesis using an in vitro translation assay in a fungal system. Mutants resistant to this compound were isolated in Saccharomyces cerevisiae and were demonstrated to contain amino acid substitutions in eIF5B that conferred the resistance. These results suggest that eIF5B is a target of potential antifungal compound and that mutation of eIF5B can confer resistance. Subsequent identification of 16 other mutants revealed that primary mutations clustered mainly on domain 2 of eIF5B and secondarily mainly on domain 4. Domain 2 has been implicated in the interaction with the small ribosomal subunit during initiation of translation. The tested translation inhibitor could act by weakening the functional contact between eIF5B and the ribosome complex. This data provides the basis for the development of a new family of antifungals.