• 치위생과학회지
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• 제10권5호
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• pp.395-401
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• 2010

본 연구는 상아모세포의 분화, 상아질의 형성, 치근 형성에 중요한 역할을 하는 NFI-C가 치아에 미치는 영향과 NFI-C 결손 생쥐에서 NFI-C와 TGF-${\beta}$의 신호전달물질인 Smad4의 발현양상을 알아보았다. 이를 위해 NFI-C 결손 생쥐치아를 광학 현미경과 면역조직적 화학방법을 사용하여 다음과 같은 결과를 얻었다. 1. NFI-C 결손생쥐는 전치부의 경우 법랑질이 있는 치관 부위는 상아질이 정상적으로 형성되었지만 법랑질이 없는 설면 부위는 개방되어 있었고 뼈모양 상아질이 관찰되었다. 2. NFI-C 결손생쥐는 구치부의 경우 법랑질이 있는 치관 부위는 상아질이 정상적으로 형성되었지만 법랑질이 없는 치근부위의 치근은 짧아졌고 상아모세포의 수가 줄었으며 약간의 뼈모양 상아질이 관찰되었다. 이는 NFI-C결손이 상아모세포 분화에 영향을 끼쳐 비정상적인 치근을 만드는 것을 보여준다. 3. NFI-C 결손생쥐의 Smad4 발현은 정상 생쥐에 비해서 핵에 더 많은 발현을 보였다. 이는 Smad4가 NFI-C와 TGF-${\beta}$의 신호전달물질로서 그 사이에서 균형을 맞추면서 상아모세포 분화에 영향을 미친다는 것을 보여준다.

• 원예과학기술지
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• 제34권3호
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• pp.433-441
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• 2016

Clubroot caused by the protist Plasmodiophora brassicae is one of the most destructive diseases of Brassica crops. Developing Chinese cabbage cultivars with durable clubroot resistance (CR) is an important goal of breeding programs, which will require new genetic resources to be identified and introduced. In this study, we evaluated resistance to P. brassicae race 4 using 26 Chinese cabbage (B. rapa ssp. pekinensis ) cultivars compared to the clubroot-susceptible Chinese cabbage inbred line 'BP079' and the clubroot-resistant European turnip (B. rapa ssp. rapifera ) inbred line 'IT033820'. No symptoms of clubroot disease were found in 'IT033820' infected with P. brassicae race 4, whereas the Chinese cabbage cultivars exhibited disease symptoms to various degrees. The Chinese cabbage cultivars that were reported to be clubroot-susceptible were susceptible to P. brassicae race 4; however, seven of the 20 cultivars reported to be clubroot-resistant were susceptible to this race of P. brassicae to varying degrees. Resting spores of P. brassicae were abundant within the infected root tissues of 'BP079', as revealed by light microscopy and scanning electron microscopy (SEM), but they were not detected in root tissues of 'IT033820'. Although resting spores were not detected by light microscopy in root tissues of the clubroot-resistant Chinese cabbage cultivar 'Kigokoro 75', a few spores were observed by SEM. The $F_1$ hybrids from a cross between 'IT033820' and 'BP079' showed no disease symptoms, and all $BC_1P_1$ progenies from a cross between the $F_1$ hybrid and 'IT033820' exhibited a resistance phenotype. In the $BC_1P_2$ population from a cross between the $F_1$ hybrid and 'BP079', this trait segregated at a ratio of 3(R):1(S) (${\chi}^2=1.333$, p = 0.248) at a 5% significance level. Inoculated $BC_1P_2$ plants were either highly resistant or highly susceptible to the pathogen, indicating that the CR to race 4 of P. brassicae carried by 'IT033820' is dominant. In the $F_2$ population, this trait segregated at a ratio of 15(R):1(S) (${\chi}^2=0.152$, p = 0.696) at a 5% significance level, suggesting that CR in 'IT033820' is mainly controlled by two dominant genes. Therefore, 'IT033820' represents a promising genetic resource for developing durable CR breeding lines in Chinese cabbage.

• 한국육종학회지
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• 제41권4호
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• pp.482-487
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• 2009

사과 대목 M.26은 준왜성대목으로 뿌리의 토양 지지력이 약해 지주 재배를 해야 하는 단점이 있다. 발근력이 향상된 M.26 왜성 대목 형질전환체를 육성하기 위하여 rolC 유전자 전환을 실시하였다. 항생제가 첨가된 재분화 선발 배지에서 재분화된 M.26 신초 1개체의 genomic DNA를 추출하여 PCR과 Southern 분석을 실시한 결과 유전자의 도입을 확인할 수 있었다. 유전자 도입이 확인된 형질전환체의 기내 발근 상태에서의 식물체 특성을 조사한 결과 대조구에 비해 신초 길이가 감소되었고 발근력이 증가된 것을 확인할 수 있었다. 격리 온실에서 생육시켰을 때 rolC 유전자 고유 특성 중 하나인 분지가 발생되었고, 실생 대목에 접목한 후 묻어떼기를 통한 발근력을 조사한 결과 발근이 현저히 향상되었음을 확인할 수 있었다. 이상에서 확인된 rolC 유전자의 도입에 의한 M.26 사과 대목의 발근력 향상과 동시에 왜화 효과를 검정하기 위해서는 실제 품종과의 접목을 통해서 기존 대목과의 왜화도 차이를 비교할 필요가 있다고 판단되었다.

• Journal of Plant Biotechnology
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• 제41권1호
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• pp.56-63
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• 2014

무의 가공용 품종의 가공 수율이 현재 약 70%로 버리는 부분이 많아 뿌리의 형태가 가공에 유리하도록 상부와 하부의 굵기가 유사한 품종을 육성코자 하였으며 웅성불임을 이용하여 채종함으로 종자의 순도도 높이고자 본 연구를 실시하였다. 가공용 품종은 특히 순도가 높아야 하므로 계통 육성 과정에서 순계로 고정되었는지 여부를 확인하기 위해 표현형 뿐 아니라 분자표지를 활용하여 증식된 종자의 순도를 검정하였다. 우수 품종 육성을 위해 A친은 ('관동여름' ${\times}$ '계룡봄무')의 후대에서 위황병에 저항성이며 추대성이 늦고 고온기 재배에서 근비대성이 타 계통보다 양호한 담록수 계통을 고정하였고, B친은 ('태상왕' ${\times}$ '서울봄무')의 후대에서 위황병, 근류병에 저항성이며 잎색은 진한 녹색으로 청수색이 강하고 근비대성, 육질치밀성인 계통을 선발 고정하였다. 화분친(C친)은 개체선발법으로 세대를 진전하였으며 분리세대 순도검정을 위해 각 세대별로 종자 48점을 ACMP-490, cnu-316 프라이머를 이용하여 분석한 결과 분리 1 세대 ACMP-490은 64.6%, cnu-316은 66.7%의 고정율을 보였으며, 분리 2세대 ACMP-490은 68.8%, cnu-316은 70.8%의 고정율을 보였고, 분리 3 세대 ACMP-490은 93.8%, cnu-316은 100%의 고정율을 나타냈으며, 분리 4 세대 ACMP-490은 93.8%, cnu-316은 100%의 고정율을 보였고, 분리 5 세대 ACMP-490은 95.8%, cnu-316은 100%의 고정율을 보였고, 분리 6세대 ACMP-490은 100%, cnu-316은 100%의 고정율을 보여 원원종을 확보하였다. 고정이 확인된 계통을 이용하여 조합을 작성한 결과 뿌리의 형태가 가공에 적합하고 순도가 우수하여 이를 'YR 오래(YR ORE)'로 2011년에 품종보호 출원하여 2013년 신품종으로 등록 되었다(품종보호 제 4550호, 2013.06.10.).

• Nutrition Research and Practice
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• 제8권5호
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• pp.526-532
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• 2014

BACKGROUND/OBJECTIVES: Acanthopanax sessiliflorus is a native Korean plant and used as a traditional medicine or an ingredient in many Korean foods. The free radical theory of aging suggests that cellular oxidative stress caused by free radicals is the main cause of aging. Free radicals can be removed by cellular anti-oxidants. MATERIALS/METHODS: Here, we examined the anti-oxidant activity of Acanthopanax sessiliflorus extract both in vitro and in vivo. Survival of nematode C. elegans under stress conditions was also compared between control and Acanthopanax sessiliflorus extract-treated groups. Then, anti-aging effect of Acanthopanax sessiliflorus extract was monitored in C. elegans. RESULTS: Stem extract significantly reduced oxidative DNA damage in lymphocyte, which was not observed by leaves or root extract. Survival of C. elegans under oxidative-stress conditions was significantly enhanced by Acanthopanax sessiliflorus stem extract. In addition, Acanthopanax sessiliflorus stem increased resistance to other environmental stresses, including heat shock and ultraviolet irradiation. Treatment with Acanthopanax sessiliflorus stem extract significantly extended both mean and maximum lifespan in C. elegans. However, fertility was not affected by Acanthopanax sessiliflorus stem. CONCLUSION: Different parts of Acanthopanax sessiliflorus have different bioactivities and stem extract have strong anti-oxidant activity in both rat lymphocytes and C. elegans, and conferred a longevity phenotype without reduced reproduction in C. elegans, which provides conclusive evidence to support the free radical theory of aging.

• Journal of Applied Biological Chemistry
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• 제49권4호
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• pp.148-153
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• 2006

While the underlying molecular mechanism remains to be elucidated, recent studies suggest that polar auxin transport is a key controlling factor in triggering differential growth responses to gravity. Identification of regulatory components in auxin-mediated differential cell expansion would improve our understanding of the gravitropic response. In this study, we identify a mutant designated aux1-like(later changed to aux1), an allele of the aux1 mutant that exhibits a severely disrupted root gravitropic response, but no defects in developmental processes. In Arabidopsis, AUX1 encodes an auxin influx carrier. Since in-depth characterization of the gravitropic response caused by mutations in this gene has been performed previously, we focused on identifying the downstream genes that were differentially expressed compared to wild-type plants. Consistent with the mutant phenotype, the transcription of the auxin-responsive genes IAA17 and GH3 were altered in aux1 plants treated with IAA, 2, 4-D and NAA. In addition, we identified two expansin genes EXP10 and EXPL3 that exhibited different expression in wild-type and mutant plants.

• Mycobiology
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• 제29권1호
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• pp.19-26
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• 2001

Defense mechanisms against anthracnose disease caused by Colletotrichum orbiculare on the leaf surface of cucumber plants after pre-treatment with plant growth promoting rhizobacteria(PGPR), amino salicylic acid(ASA) or C. orbiculare were compared using a fluorescence microscope. Induced systemic resistance was mediated by the pre-inoculation in the root system with PGPR strain Bacillus amylolquefaciens EXTN-1 that showed direct antifungal activity to C. gloeosporioides and C. orbiculare. Also, systemic acquired resistance was triggered by the pre-treatments on the bottom leaves with amino salicylic acid or conidial suspension of C. orbiculare. The protection values on the leaves expressing SAR were higher compared to those expressing ISR. After pre-inoculation with PGPR strains no change of the plants was found in phenotype, while necrosis or hypersensitive reaction(HR) was observed on the leaves of plants pre-treated with ASA or the pathogen. After challenge inoculation, inhibition of fungal growth was observed on the leaves expressing both ISR and SAR. HR was frequently observed at the penetration sites of both resistance-expressing leaves. Appressorium formation was dramatically reduced on the leaves of plants pre-treated with ASA, whereas EXTN-1 did not suppress the appressorium formation. ASA also more strongly inhibited the conidial germination than EXTN-1. Conversely, EXTN-1 significantly increased the frequency of callose formation at the penetration sites, but ASA did not. The defense mechanisms induced by C. orbiculare were similar to those by ASA. Based on these results it is suggested that resistance mechanisms on the leaf surface was different between on the cucumber leaves expressing ISR and SAR, resulting in the different protection values.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1737-1746
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• 2013

IbMYB1, a transcription factor (TF) for R2R3-type MYB TFs, is a key regulator of anthocyanin biosynthesis during storage of sweet potatoes. Anthocyanins provide important antioxidants of nutritional value to humans, and also protect plants from oxidative stress. This study aimed to increase transgenic potatoes' (Solanum tuberosum cv. LongShu No.3) tolerance to environmental stress and enhance their nutritional value. Transgenic potato plants expressing IbMYB1 genes under the control of an oxidative stress-inducible peroxidase (SWPA2) promoter (referred to as SM plants) were successfully generated through Agrobacterium-mediated transformation. Two representative transgenic SM5 and SM12 lines were evaluated for enhanced tolerance to salinity, UV-B rays, and drought conditions. Following treatment of 100 mM NaCl, seedlings of SM5 and SM12 lines showed less root damage and more shoot growth than control lines expressing only an empty vector. Transgenic potato plants in pots treated with 400 mM NaCl showed high amounts of secondary metabolites, including phenols, anthocyanins, and flavonoids, compared with control plants. After treatment of 400 mM NaCl, transgenic potato plants also showed high DDPH radical scavenging activity and high PS II photochemical efficiency compared with the control line. Furthermore, following treatment of NaCl, UV-B, and drought stress, the expression levels of IbMYB1 and several structural genes in the flavonoid biosynthesis such as CHS, DFR, and ANS in transgenic plants were found to be correlated with plant phenotype. The results suggest that enhanced IbMYB1 expression affects secondary metabolism, which leads to improved tolerance ability in transgenic potatoes.

• Journal of Ginseng Research
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• 제41권3호
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• pp.419-427
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• 2017

Background: Glycosylation of natural compounds increases the diversity of secondary metabolites. Glycosylation steps are implicated not only in plant growth and development, but also in plant defense responses. Although the activities of uridine-dependent glycosyltransferases (UGTs) have long been recognized, and genes encoding them in several higher plants have been identified, the specific functions of UGTs in planta remain largely unknown. Methods: Spatial and temporal patterns of gene expression were analyzed by quantitative reverse transcription (qRT)-polymerase chain reaction (PCR) and GUS histochemical assay. In planta transformation in heterologous Arabidopsis was generated by floral dipping using Agrobacterium tumefaciens (C58C1). Protein localization was analyzed by confocal microscopy via fluorescent protein tagging. Results: PgUGT72AL1 was highly expressed in the rhizome, upper root, and youngest leaf compared with the other organs. GUS staining of the promoter: GUS fusion revealed high expression in different organs, including axillary leaf branch. Overexpression of PgUGT72AL1 resulted in a fused organ in the axillary leaf branch. Conclusion: PgUGT72AL1, which is phylogenetically close to PgUGT71A27, is involved in the production of ginsenoside compound K. Considering that compound K is not reported in raw ginseng material, further characterization of this gene may shed light on the biological function of ginsenosides in ginseng plant growth and development. The organ fusion phenotype could be caused by the defective growth of cells in the boundary region, commonly regulated by phytohormones such as auxins or brassinosteroids, and requires further analysis.

• Journal of Ginseng Research
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• 제44권2호
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• pp.321-331
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• 2020

Background: The patatin-related phospholipase AIII family (pPLAIIIs) genes alter cell elongation and cell wall composition in Arabidopsis and rice plant, suggesting diverse commercial purposes of the economically important medicinal ginseng plant. Herein, we show the functional characterization of a ginseng pPLAIII gene for the first time and discuss its potential applications. Methods: pPLAIIIs were identified from ginseng expressed sequence tag clones and further confirmed by search against ginseng database and polymerase chain reaction. A clone showing the highest homology with pPLAIIIβ was shown to be overexpressed in Arabidopsis using Agrobacterium. Quantitative polymerase chain reaction was performed to analyze ginseng pPLAIIIβ expression. Phenotypes were observed using a low-vacuum scanning electron microscope. Lignin was stained using phloroglucinol and quantified using acetyl bromide. Results: The PgpPLAIIIβ transcripts were observed in all organs of 2-year-old ginseng. Overexpression of ginseng pPLAIIIβ (PgpPLAIIIβ-OE) in Arabidopsis resulted in small and stunted plants. It shortened the trichomes and decreased trichome number, indicating defects in cell polarity. Furthermore, OE lines exhibited enlarged seeds with less number per silique. The YUCCA9 gene was downregulated in the OE lines, which is reported to be associated with lignification. Accordingly, lignin was stained less in the OE lines, and the expression of two transcription factors related to lignin biosynthesis was also decreased significantly. Conclusion: Overexpression of pPLAIIIβ retarded cell elongation in all the tested organs except seeds, which were longer and thicker than those of the controls. Shorter root length is related to auxinresponsive genes, and its stunted phenotype showed decreased lignin content.