• Molecules and Cells
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• 제42권4호
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• pp.356-362
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• 2019

The binding of MS2 bacteriophage coat protein (MCP) to MS2 binding site (MBS) RNA stem-loop sequences has been widely used to label mRNA for live-cell imaging at single-molecule resolution. However, concerns have been raised recently from studies with budding yeast showing aberrant mRNA metabolism following the MS2-GFP labeling. To investigate the degradation pattern of MS2-GFP-labeled mRNA in mammalian cells and tissues, we used Northern blot analysis of ${\beta}$-actin mRNA extracted from the Actb-MBS knock-in and $MBS{\times}MCP$ hybrid mouse models. In the immortalized mouse embryonic cell lines and various organ tissues derived from the mouse models, we found no noticeable accumulation of decay products of ${\beta}$-actin mRNA compared with the wild-type mice. Our results suggest that accumulation of MBS RNA decay fragments does not always happen depending on the mRNA species and the model organisms used.

• 생명과학회지
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• 제27권12호
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• pp.1494-1499
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• 2017

Candida albicans에 의한 구강 감염(캔디다증)은 구강 점막에 빈번하게 발생하며 잘 알려진 질병이다. 구강 캔디다증은 생명을 위협하는 정도의 곰팡이 감염증은 아니나, 특정상황에서 개인에게 심각한 위험을 초래할 수도 있다. 마이크로 RNA는 세포 내에서 다른 타겟 유전자를 저해하는 작은 크기의 RNA 분자이며 단백질을 코딩하지는 않고 번역과정을 억제하는 조절자로서의 역할을 하고 있다. 본 연구는 C. albicans의 마이크로RNA를 처음으로 동정하고 그러한 마이크로RNA가 지닌 기능을 조사하기 위함이다. 이를 위하여 C. albicans의 small RNA를 차세대 염기분석법을 통하여 분석하고 그러한 RNA들의 2차 구조를 생물정보학적 방법으로 조사하였다. 분석한 small RNA들은 마이크로 RNA라고 불리울 수 있는 특징들을 가지고 있었으며, 특별히 높게 발현되고 있는 두개의 마이크로 RNA 정도 크기의 RNA가 CBP1 유전자의 3' 말단 비번역구역(UTR)에서 반대방향으로 발현하는 것을 밝혀 내었다. 우리는 이러한 C. albicans의 RNA가 CBP1 유전자를 타겟으로 하여 조절하는지 알아보기 위해 RNA를 인위적으로 합성한 후 세포 내로 주입하고, 형광형미경으로 도입 사실을 확인하였다. 하지만 4시간과 8시간 후에 CBP1의 발현 변화는 관찰되지 않았다. 따라서, 이러한 결과는 C. albicans가 마이크로RNA에 의한 RNA 간섭(RNAi) 작용이 다른 진핵세포와는 다르게 작용하는 것을 알 수 있다.

• Genomics & Informatics
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• 제14권1호
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• pp.29-33
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• 2016

A retron is a bacterial retroelement that encodes an RNA gene and a reverse transcriptase (RT). The former, once transcribed, works as a template primer for reverse transcription by the latter. The resulting DNA is covalently linked to the upstream part of the RNA; this chimera is called multicopy single-stranded DNA (msDNA), which is extrachromosomal DNA found in many bacterial species. Based on the conserved features in the eight known msDNA sequences, we developed a detection method and applied it to scan National Center for Biotechnology Information (NCBI) RefSeq bacterial genome sequences. Among 16,844 bacterial sequences possessing a retron-type RT domain, we identified 48 unique types of msDNA. Currently, the biological role of msDNA is not well understood. Our work will be a useful tool in studying the distribution, evolution, and physiological role of msDNA.

• 한국식물병리학회지
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• 제11권2호
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• pp.173-178
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• 1995

동물계에서 항바이러스와관련된 dsRNA 의존성 인산화 효소(PKR)의 유전자를 식물체에서 발현시킬 경우 PKR에 의한 단백질합성 및 식물바이러스의 증식조절 가능성에 대한 기초자료를 확보하기 위하여 사람에서 분리된 PKR cDNA를 Agrobacterium 방법에 의하여 연초식물체(Nicotiana tabacum cv. Xanthi-nc)로 형질전환시켰다. HindIII/PstI처리에 의해 얻어지는 약 1.8kb의 phPKR cDNA절편을 일련의 유전자 조작 방법을 통하여 식물발현벡터인 pBI121에 도입하여, p12168을 재조합하였다. 이를 A. tumefaciens LBA 4404에 형질전환시켜 연초식물체형질 전환에 이용하였다. 2mg/l BA와 0.5mg/l NAA가 포함되고 100$\mu\textrm{g}$/ml의 kanamycin이 첨가된 MS배지에서 shooting시킨 후 phytohormone이 첨가되지 않은 MS배지상에서 rooting을 시켜 형질전환 연초식물체를 얻었으며, 형질전환식물체는 정상식물체와 유사한 생육양상을 나타내었다. 형질전환식물체의 유전자도입은 hPKR cDNA의 전사부여는 RT-PCR 방법에 의하여 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제21권4호
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• pp.421-429
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• 2011

For precise identification of a Lactobacillus K1 isolate, LC-MS/MS analysis of the putative surface layer protein was performed. The results obtained from LTQ-FT-ICR mass spectrometry confirmed that the analyzed protein spot is the surface layer protein originating from Lb. helveticus species. Moreover, the identified protein has the highest similarity with the surface layer protein from Lb. helveticus R0052. To evaluate the proteomic study, multilocus sequence analysis of selected housekeeping gene sequences was performed. Combination of 16S rRNA sequencing with partial sequences for the genes encoding the RNA polymerase alpha subunit (rpoA), phenylalanyl-tRNA synthase alpha subunit (pheS), translational elongation factor Tu (tuf), and Hsp60 chaperonins (groEL) also allowed to classify the analyzed isolate as Lb. helveticus. Further classification at the strain level was achieved by sequencing of the slp gene. This gene showed 99.8% identity with the corresponding slp gene of Lb. helveticus R0052, which is in good agreement with data obtained by nano-HPLC coupled to an LTQ-FT-ICR mass spectrometer. Finally, LC-MS/MS analysis of surface layer proteins extracted from three other Lactobacillus strains proved that the proposed method is the appropriate molecular tool for the identification of S-layer-possessing lactobacilli at the species and even strain levels.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1537-1541
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• 2015

Previous detection methods for Citrobacter are considered time consuming and laborious. In this study, we have developed a rapid and accurate detection method for Citrobacter species in pork products, using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). A total of 35 Citrobacter strains were isolated from 30 pork products and identified by both MALDI-TOF MS and 16S rRNA gene sequencing approaches. All isolates were identified to the species level by the MALDI-TOF MS, while 16S rRNA gene sequencing results could not discriminate them clearly. These results confirmed that MALDITOF MS is a more accurate and rapid detection method for the identification of Citrobacter species.

• 생명과학회지
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• 제9권1호
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• pp.29-34
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• 1999

들깨로부터 callus의 유기 및 재분화를 위해 MS 기본배지에 생장조정제 NAA(0.1, 0.5, 1.0, 및 2.0mg/$\ell$)와 BA(0.5, 1.0 및 1.5mg/$\ell$)를 혼용하여 자엽과 하배축 조직을 치상하고 3, 4, 5 및 6주로 나누어 재분화과정과 구성성분의 변화를 조사한 결과, BA 0.5mg/$\ell$과 NAA 0.5mg/$\ell$을 첨가한 배지에서 자엽과 하배축 모두 callus의 유기 및 재분화 정도가 좋았고, 자엽절편의 뿌리 발생은 BA 0.5mg/$\ell$과 NAA 0.1mg/$\ell$을 첨가한 배지에서만 발생하였다. 배양기간의 경과에 따라 단백질함량은 증가한 반면 RNA 함량은 감소하였고, polypeptide pattern은 배양전 자엽조직에서는 30KD과 45KD의 polypeptide가 진하게 나타났고, 30KD polypeptide는 배양기간의 경과에 따라 증가 하였다.

• 생명과학회지
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• 제11권1호
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• pp.19-23
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• 2001

To develop the effective microbial screening method, pyrolysis mass spectrometry (PyMS) fingerprinting was evaluated as a tool that discriminate various yeast strains. The target yeast strains were isolated from industrial wastewater. Seventeen environmental isolated yeast strains were examined by pyrolysis mass spectrometry and sequencing analysis of the large subunit rRNA gene D1/D2 region. The PyMS results were compared with those of sequencing analysis. Taxonomic correlations were observed between the PyMS data and the sequencing results. It was concluded that PyMS provides a rapid, reliable and cost-reducing method for discrimination of the yeast strains.

• Journal of Microbiology
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• 제42권3호
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• pp.200-204
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• 2004

Retron is a prokaryotic genetic element that produces multicopy single-stranded DNA covalently linked to RNA (msDNA) by a reverse transcriptase. It was found that cells producing a large amount of msDNA, rather than those that did not, showed a higher rate of mutation. In order to understand the molecular mechanism connecting msDNA production to the high mutation rate the protein patterns were compared by two dimensional gel electrophoresis. Ten proteins were found to be differentially expressed at levels more than three fold greater in cells with than without msDNA, nine of which were identified by MALDI TOF MS. Eight of the nine identified proteins were repressed in msDNA-producing cells and, surprisingly, most were proteins functioning in the dissimilation of various carbon sources. One protein was induced four fold greater in the msDNA producing cells and was identified as a 30S ribosomal protein S2 involved in the regulation of translation. The molecular mechanism underlying the elevated mutation in msDNA-producing cell still remains elusive.

• Journal of Photoscience
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• 제11권1호
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• pp.35-40
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• 2004

[Ru(2,2'-bipyridine)$_2$(4,4'-dicarboxy-2,2'-bipyridine)]$^{2+}$(RuBDc) is a very photostable probe that possesses favorable photophysical properties including long lifetime, high quantum yield, large Stokes' shift, and highly polarized emission. To evaluate the usefulness of this luminophore (RuBDc) for studying macromolecular dynamics, its intensity and anisotropy decays when conjugated to RNA bacteriophage MS2 were examined using frequency-domain fluorometry with a high-intensity, blue light-emitting diode (LED) as the modulated light source. The intensity decays were best fit by a sum of two exponentials, and the mean intensity decay time was 442.2 ns. The anisotropy decay data showed a single rotational correlation time (2334.9 ns), which is typical for a spherical molecule. The use of RuBDc enabled us to measure the rotational correlation time up to several microseconds. These results indicate that RuBDc can be useful for studying rotational diffusion of biological macromolecules.s.