• Journal of Microbiology and Biotechnology
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• 제8권1호
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• pp.14-20
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• 1998

Syntheses of the B. stearothermophilus xylanolytic enzymes such as xylanases, ${\beta}$-xylosidases, ${\alpha}$-arabinofurano-sidases, and esterases, were observed to be regulated by the carbon source present in the culture media. Xylan induced synthesis of ${\beta}$-xylosidase at the highest level while xylose gave about 30% of the ${\beta}$-xylosidase activity induced by xylan. The lowest syntheses of the xylanolytic enzymes above mentioned were detected in the basal medium containing glucose as a sole carbon source. When a mixture of xylan and glucose was used as a carbon source, we could observe glucose repression of xylanase (about 70-fold) and ${\beta}$-xylosidase (about 40-fold) syntheses. Whereas, the level of the glucose repression of the expression of the xylA gene encoding the major ${\beta}$-xylosidase of B. stearothermophilus was assessed to be about l0-fold when the relative amounts of the xylA transcript were determined. From the sequence of the xylA gene, we could find two CRE-like sequences (CRE-l: nucleotides ＋124 to ＋136 and CRE-2:＋247 to ＋259) within the reading frame of the xylA gene, either or both of which were suspected to be involved in catabolite repression of the xylA gene.

• 한국식물병리학회지
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• 제11권1호
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• pp.66-72
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• 1995

The coat protein (CP) gene of cucumber mosaic virus-As (CMV-As) strain was engineered for expression in the plant by using the cauliflower mosaic virus 35S transcript regulatory sequences. The CP gene was cloned into an Agrobacterium-derived binary vector. A chimeric gene was constructed by the cDNA of CMV-As CP and plant expression vector pBI121. The clone, pCMAS66, was first introduced into the phagemid vector pSPORT1 for situating sense orientation for translation and making restriction sites in order to re-introduce plant expression vector, pHI121. The resulting subclone pCASCP02 and plant expression vector pBI121 were treated with BamHI-SacI for excising the target gene and removing GUS gene, respectively. After Agrobacterium transformation by freeze-thaw technique, the clone, pCMASCP121-123 which contains sense orientation of the target gene, was selected and confirmed by restriction endonuclease analysis. The CMV-As CP gene was introduced into A. tumefaciens. The results on tobacco plant transformation with the vector system revealed that the system could be successfully introduced and showed high frequency of selection to putative transformations.

• Molecules and Cells
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• 제41권10호
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• pp.917-922
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• 2018

The CRISPR-Cas system is a well-established RNA-guided DNA editing technique widely used to modify genomic DNA sequences. I used the CRISPR-Cas9 system to change the second and third nucleotides of the triplet $T{\underline{CT}}$ of human TNSFSF9 in HepG2 cells to $T{\underline{AG}}$ to create an amber stop codon. The $T{\underline{CT}}$ triplet is the codon for Ser at the $172^{nd}$ position of TNSFSF9. The two substituted nucleotides, AG, were confirmed by DNA sequencing of the PCR product followed by PCR amplification of the genomic TNFSF9 gene. Interestingly, sequencing of the cDNA of transcripts of the edited TNFSF9 gene revealed that the $T{\underline{AG}}$ had been re-edited to the wild type triplet $T{\underline{CT}}$, and 1 or 2 bases just before the triplet had been deleted. These observations indicate that CRISPR-Cas9-mediated editing of bases in target genomic DNA can be followed by spontaneous re-editing (correcting) of the bases during transcription.

• Molecules and Cells
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• 제22권1호
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• pp.89-96
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• 2006

"Determinate" and "indeterminate" inflorescences in plants are controlled by a single recessive gene, for example, SELF-PRUNING (SP) in Solanum lycopersicum, TERMINAL FLOWER1 in Arabidopsis, CENTRORADIALIS in Antirrhinum, and CENTRORADIALIS-like gene in tobacco. Pepper (Capsicum annuum L.) is an indeterminate species in which shoots grow indefinitely. In this study, we cloned and characterized the pepper SP-like gene (CaSP). RT-PCR revealed that the CaSP transcript accumulates to higher levels in floral buds than in other organs. Comparison of genomic DNA and cDNA sequences from indeterminate and determinate pepper plants revealed the insertion of a single base in the first exon of CaSP in the determinate pepper plants. CaSP is annotated in linkage group 8 (chromosome 6) of the SNU2 pepper genetic map and showed similar synteny to SP in tomato. Transgenic tobacco plants overexpressing CaSP displayed late-flowering phenotypes similar to the phenotypes caused by overexpression of CaSP orthologs in other plants. Collectively, these results suggest that pepper CaSP is an ortholog of SP in tomato.

• Molecules and Cells
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• 제22권3호
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• pp.269-274
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• 2006

In order to characterize saikosaponin biosynthesis in Bupleurum falcatum, the expression of five isoprenoid pathway genes and their relationship to saikosaponin accumulation in the hairy roots were analyzed. The hairy roots exhibited a rapid accumulation of saikosaponins when incubated in a root culture medium (3XRCM). Homology-based RT-PCR was used to isolate core fragments of five genes, HMGR, IPPI, FPS, SS, and OSC, from the hairy roots. The deduced amino acid sequences exhibited amino acid identities of more than 85% to previously reported genes. Using the fragments as probes, the expression of these five genes in the hairy roots during incubation in 3XRCM medium was examined. Expression of all five genes in the hairy roots increased soon after incubation. In particular, the SS and OSC genes were coordinately induced at 8 days of incubation, and their expression persisted throughout the incubation period. A quantitative HPLC analysis showed that the saikosaponin content of the hairy root culture also began to increase at 8 days of culture. The correlation between SS transcript level and saikosaponin content in the hairy roots suggests that transcriptional regulation plays a regulatory role in saikosaponin biosynthesis.

• Journal of Plant Biotechnology
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• 제40권2호
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• pp.102-110
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• 2013

The novel BrRZFPs genes encoding C3HC4-type RING zinc finger protein were identified from FOX (full length cDNA over-expressing) library of Brassica rapa. Ten full-length cDNAs obtained from the library encode zinc-finger protein containing 346 amino acids, designated BrRZFPs. These genes were classified into four groups by phylogenic analysis showing conserved protein sequences at both termini. The tissue distribution of BrRZFPs transcription was examined by qRT-PCR revealing ubiquitous expression pattern. However, each gene was strongly expressed in the specific tissue. Transcriptional analysis showed that those acquired 10 genes were inducible under abiotic stresses. Likewise, the transcript of BrRZFP3 was strongly induced (~12-folds) by exogenous abscisic acid, whereas the transcripts of BrRZFP1, BrRZFP2 and BrRZFP3 were (> 9-folds) induced by cold. We suggest that these BrRZFPs that function as signal or response to abiotic stress are useful for crop improvement.

• 식물조직배양학회지
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• 제25권5호
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• pp.341-346
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• 1998

색소유전자의 전이를 통하여 새로운 색소발현체계를 가진 품종을 육종하기 위한 기초연구로 stock (Matthiola incana R. Br.)의 꽃봉오리로부터 cDNA-library를 합성하였고 screening을 통하여 anthocyanin 합성경로의 중요효소의 하나인 DFR (dihydroflavonol 4-reductase) 유전자를 분리하였다. 염기서열분석을 수행하여 분리유전자의 크기가 1450bp 이며 이중 coding region은 1029 bp 임을 확인하였다. 이미 밝혀진 다른 식물체의 DFR 유전자와 서로 염기서열의 일치성을 비교해 본 결과 외자엽식물인 옥수수와 보리와는 각각 61%를 보였으며, 쌍자엽식물인 페튜니아, 금어초, 거베라, 과꽃 그리고 카네이션 등 과는 66%-67%의 일치성을 나타내었다. 아울러 염기서열의 G/C 함량분석을 통하여 쌍자엽식물의 G/C 함량은 외자엽식물의 그것에 비해 매우 낮은 수치를 나타내었다. 분리유전자의 발현을 확인하기 위하여 인위적으로 기내에서의 전사와 해석을 수행한 결과 42-44 kd 크기의 단백질을 확인하였다. Southern blot 분석의 결과 DFR 유전자는 stock의 genome에 다른 대부분의 식물체와 유사하게 한 개가 존재하며 야생종과 돌연변이종의 stock을 분리 DFR 유전자를 probe 로 Northern blot 분석을 수행하여 돌연변이종인 lineK17b가 DFR 돌연변이임을 확인하였다.

• Applied Biological Chemistry
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• 제39권2호
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• pp.112-117
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• 1996

ADC는 diamine인 putrescine 생합성의 두가지 경로중에서 식물계에서 특히 중요한 효소이며, ADC 유전자는 E. coli, 귀리, 토마토 genome에서 이미 cloning된 바 있다. 벼 (Oryza sativa L.) 게놈 DNA의 PCR 증폭을 위해서 토마토와 E. coli의 ABC cDNA의 보존된 부분과 일치하는 두개의 degenerate oligonucleotides (17mer)를 인위 합성하였으며, 증폭의 결과 약 1 kbp 크기의 DNA가 관찰되었다. 증폭된 DNA 절편은 1,022bp 염기서열을 포함하고 있는 ORE (open reading frame)으로 확인되었다. 이 PCR product는 POEM-originated T vector에 재조합하였으며 PstI 제한효소로 약 500bp 크기로 절단하여 pGEM-3Zf(+/-) vector에 subcloning하였다. 벼 ADC clone의 염기서열은 귀리와 토마토 ADC cDNA 서열의 같은 부분과 각각 74%와 70%의 동질성을 갖는 것으로 나타났으며, 예상되는 아미노산 서열은 귀리와 토마토 ADC 단백질과 각각 45%와 62%의 동질성이 관찰되었다. 귀리와 E. coli, 토마토와 귀리 그리고 토마토와 E. coli ADC 아미노산 서열에서 각각 34%, 47%, 그리고 38%의 유사성 정도가 보고된 것을 비교하여 볼 때, 벼와 귀리 및 토마토 사이의 유사성 정도는 다른 비교 보다도 월등히 높았다. 벼 유묘기 잎조직에서 추출한 RNA를 이용한 Northern blot 분석에서 ADC는 약 2.5kbp의 전사체로 발현됨이 확인되었다.

• 생명과학회지
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• 제17권12호
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• pp.1610-1615
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• 2007

마가목 속(genus Sorbus)은 목본류로 아시아와 유럽에 분포되어 있다. 마가목 속 식물은 한국과 중국에서 약용으로 쓰인다. 한국내 마가목 속 식물에 대해 ITS에 의한 계통관계를 조사하였다 마가목 속 전체 종에서 5.8S exon은 165 핵산서열이었다. ITS1은 유럽마가목(S. aucuparia)에서 218 핵산서열인 반면 한국 내 마가목 종은 219 핵산서열이었다. ITS2 핵산서 열은 다양하였는데 S. sambucifolia var. pseudogricilisto에서 는 240 핵산서 열로 가장 적은 반면 S. aucuparia에서는 245 핵산서열이었다. ITS 전체 서열은 625개로 35개는 절약법에 정보적이었다. ITS 서 열로 한국내 분류군과 유럽종간 구분이 잘 되었다. RNA 2차 구조 추정 분석에서 도메인 I과 II는 마가목 속에 잘 보전되어 있는 반면 도메인 III에서는 많은 차이를 나타내었다. ITS 서열로 종 동정에 이용할 수 있었으며, 종의 보전이나 생식질 보전에 기초로 이용될 수 있을 것으로 사료된다.

• Journal of Plant Biotechnology
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• 제2권2호
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• pp.61-71
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• 2000

By screening a cDNA library of auxin-treated mung bean (Vigna radiata L.) hypocotyls, we have isolated two full-length cDNA clones, pVR-ACS6 and pVR-ACS7, for 1-aminocyclopropane-1-carboxylate (ACC) synthase, the rate-limiting enzyme in the ethylene biosynthetic pathway. While PVR-ACS6 corresponds to the previously identified PCR fragment pMBA1, pVR-ACS7 is a new cDNA clone. A comparison of deduced amino acid sequences among auxin-induced ACC synthases reveal that these enzymes share a high degree of homology (65-75%) to VR-ACS6 and VR-ACS7 polypeptides, but only about 50% to VR-ACS1 polypeptide. ACS6 and ACS7 are specifically induced by auxin, while ACS1 is induced by cycloheximide, and to lesser extent by excision and auxin treatment. Results from nuclear run-on transcription assay and RNA gel blot studies revealed that all three genes were transcriptionally active displaying unique patterns of induction by IAA and various hormones in etiolated hypocotyls. Particularly, 24-epibrassinolide (BR), an active brassinosteroid, specifically enhanced the expression of VR-ACS7 by distinct temporal induction mechanism compared to that of IAA. In addition, BR synergistically increased the IAA-induced VR-ACS6 and VR-ACS7 transcript levels, while it effectively abolished both the IAA- and kinetin-induced accumulation of VR-ACS1 mRNA. In light-grown plants, VR-ACS1 was induced by IAA in roots, whereas W-ACS6 in epicotyls. IAA- and BR-treatments were not able to increase the VR-ACS7 transcript in the light-grown tissues. These results indicate that the expression of ACC synthase multigene family is regulated by complex hormonal and developmental networks in a gene- and tissue-specific manner in mung bean plants. The VR-ACS7 gene was isolated, and chimeric fusion between the 2.4 kb 5'-upstream region and the $\beta$-glucuronidase (GUS) reporter gene was constructed and introduced into Nicotiana tobacum. Analysis of transgenic tobacco plants revealed the VR-ACS7 promoter-driven GUS activity at a highly localized region of the hypocotyl-root junction of control seedlings, while a marked induction of GUS activity was detected only in the hypocotyl region of the IAA-treated transgenic seedlings where rapid cell elongation occurs. Although there was a modest synergistic effect of BR on the IAA-induced GUS activity, BR alone failed to increase the GUS activity, suggesting that induction of VR-ACS7 occurs via separate signaling pathways in response to IAA and BR.