• Journal of Plant Biology
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• 제35권2호
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• pp.117-123
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• 1992

암배양을 통한 노쇠중인 밀 제1엽에서 지질의 과산화반응과 불용성 잎단백질의조성 및 엽록체 틸라코이드 막단백질 조성의 변화에 대한 BA의 효과가 조사되었다. 성숙한 밀 제1엽을 잘라내어 4일간의 암배양을 통한 노쇠유도실험에서 $10^{-5}\;M$ Benzyladenine(BA)은 노쇠중인 밀잎에서 엽록소 함량 및 수용성과 불용성 단백질 함량의 감소를 크게 억제시켰다. 특히, 단배질 함량 감소에 대한 BA의 억제효과는 수용성 보다는 불용성 단백질에 있어서 더욱 현저하였다. 또한, BA로 처리된 잎에서 지질의 과산화물인 MDA 함량의 증가가 억제되었다. 불용성 단백질에 대한 SDS-전기영동 결과 양적으로 현저한 57, 26 및 12 KD 단백질이 다른 소량의 단백질 무리와 함께 분리되었다. 대조구 잎에서의 불용성단백질 조성의 변화는 72시간의 암배양동안 57 KD와 12 KD 단백질이 현저하게 분해 소실되었으나 26 KD 단백질은 비교적 분해가 덜 일어났으며 BA 처리시 이들 단백질의 소실이 크게 억제되었다. 엽록체 틸라코이드막 단백질 조성의 경우, 각각 CF의 $\alpha,\;\beta$ subunits인 59 KD 단백질과 57 KD 단백질 및 LHCP 단백질인 26 KD 단백질을 포함하는 20개 정도의 단백질이 SDS-전기영동상에서 분리되었다. 72시간의 암배양 동안 대조구 엽록체에서 이들 단백질들이 급속히 분해 소실되었으나 BA로 처리된 엽록체의 경우 이들 단백질의 분해가 정량적으로 크게 억제되었다. 위의 결과들은 BA가 노쇠중인 밀잎에서 막지질의 과산화반응 억제를 통해 막단백질의 손실을 지연시키며 그로 인하여 엽록체 틸라코이드막을 포함한 세포막이 유지될 수 있음을 나타내었다.

• 한국발생생물학회지:발생과생식
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• 제21권1호
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• pp.55-62
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• 2017

We used flowcytometry to ploidy verification after that investigate difference between diploid and spontaneous triploid through the truss dimension and classical dimension at crucian carp, Carassius auratus, crucian carp C. cuvieri and common carp, Cyprinus carpio collected from Hangang river, Hantangang river, Imjingang river, Geumgang river, Yeongsangang river and Nakdonggang river, Korea. There were significant differences among the three species for the truss dimensions anterior origin of dorsal fin $(2){\times}$ anterior origin of anal fin (5), $2{\times}$ anterior origin of pelvic fin (6), $2{\times}$ origin of pectoral fin (7), posterior origin of dorsal fin $(3){\times}5$, $3{\times}6$, and $3{\times}7$ (P<0.05). There were no significant differences among the three species in the truss dimensions dorsal fin length ($2{\times}9$) and eye diameter (ED)(P>0.05). On the other hand, there were no significant differences in the several classical dimensions of each species (P>0.05). Three classical dimensions, most anterior extension of the head $(1){\times}2$, $1{\times}6$ and $2{\times}$ most posterior scale in lateral line (4) did not differ between the C. auratus diploid and spontaneous triploid (P>0.05). Two classical dimensions, $1{\times}6$ and longest length between most anterior extension of the head and gill cover ($1{\times}8$) did not differ between the C. cuvieri diploid and spontaneous triploid (P>0.05). One classical dimensions, $1{\times}2$ did not differ between the common carp diploid and spontaneous triploid (P>0.05). There were significant differences in the each diploid and triploid species (P<0.05). These results suggest that the classification of each species and classification between diploid and spontaneous triploid morphometrical parameters used in this study are useful indices of morphometrical status in the each species from major river of Korea.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.20-20
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• 2017

Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.97-97
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• 2017

Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

• 한국환경농학회지
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• 제37권1호
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• pp.57-65
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• 2018

본 연구에서는 HPLC-UVD/MS를 이용한 농산물 중 benzenesulfonamide계 살균제 flusulfamide의 잔류 분석법을 확립하였다. 대표 농산물은 사과, 고추, 배추, 현미 및 콩을 적용하였고, acetone에 의해 추출된 flusulfamide 성분을 dichloromethane 액-액 분배법과 Florisil 흡착크로마토그래피법으로 정제하여 HPLC-UVD/MS의 분석시료로 사용하였다. Flusulfamide의 정량적 분석을 위한 최적 HPLC-UVD 분석 조건을 검토하였으며, 정량한계(LOQ)는 0.02 mg/kg 이었다. 각 대표 농산물에 대해 정량한계, 정량 한계의 10배 및 50배 수준에서 회수율을 검토한 결과, 모든 처리농도에서 82.3-98.2% 수준의 회수율을 나타내었고, 반복간 변이계수(CV)는 최대 6.5%를 나타내어 잔류분석 기준인 회수율 70-120% 및 분석오차 10% 이내를 충족시키는 만족한 결과를 도출하였고, LC/MS/SIM을 이용하여 실제 농산물 시료에 적용하여 재확인 하였다. 이상의 결과로 신규 flusulfamide의 HPLC-UVD/MS 분석법은 검출한계, 회수율 및 분석오차 면에서 국제적 분석기준을 만족하는 신뢰성이 확보된 정량 분석법으로 사용 가능할 것이다.

• 식물병연구
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• 제19권2호
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• pp.84-89
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• 2013

충남지역의 벼 줄무늬잎마름병 발생변화 원인을 구명하기 위해 월동 애멸구 밀도와 보독충률, 줄무늬잎마름병 발생정도, 중간기주, 감수성 품종 등을 조사하였다. 충남지역의 월동 애멸구 밀도는 2008년부터 2010년까지 해마다 감소하였으며 월동 애멸구의 RSV 보독충률은 3년간 각각 2.9, 4.0, 그리고 3.9%로 큰 변화는 없었다. 애멸구의 중간기주로 알려진 보리와 둑새풀, 새포아풀에서 RSV의 감염은 확인되지 않았다. 2009년 중국으로부터 애멸구가 대량 비래하였고, 이들의 보독률은 5.4%이었으나 2008년과 2010년에는 비래가 확인되지 않았다. 본답에서의 줄무늬잎마름병 발생은 2008년과 2009년에 1.0% 이하로 유지되었고, 2007년부터 2009년까지 감수성품종의 재배면적 또한 41%에서 19%로 크게 감소하였다. 전염원의 대량유입으로 인한 충남지역 벼 줄무늬잎마름병의 감소 요인은 적절한 예찰과 화학적 방제, 저항성 품종의 재배, 재배방법의 변화, 그리고 겨울-봄의 낮은 온도에 의한 것으로 해석되었다.

• 대한수의학회지
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• 제42권2호
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• pp.131-136
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• 2002

The vertebrae of female African elephant (Loxodonta africana) of twenty-eight years old were observed macroscopically. The result was summarized as follows; the vertebral formula of African elephant was $C_7$ $T_{21}$ $L_3$ $S_4$ $Cd_{21}$. The total length of the vertebral column removed intervertebreal disks was 353 cm. The length of each segment of vertebral column was 44 cm in cervical, 142 cm in thoracic, 21 cm in lumbar, 27 cm in sacral and 119 cm in caudal vertebrae. The 17th and 18th thoracic vertebrae (T) were partially fused each other in four parts: the transverse processes of 17th and 18th T, caudal articular process of 17th T and cranial articular process of 18th T, left mammilary process of 18th T and left transverse process of 17th T, and vertebral arch of 17th and 18th T, respectively. Others partial fusions also observed among the third luwbar, sacrum and ilium. These were in between transverse process of third lumbar vertebra and cranial parts of wing of sacrum, lateral part of sacrum and tuber sacrale, respectively. The sternum was consisted of three pieces; one is a part of anterior prestemum, two is the part from caudal demifacet at second facet to cranial demifacet at third facet in middle mesosternum, which is divided vertically into an half at second and third facets, respectively, and the last is the part between caudal demifacet of third facet in middle mesosternum and the posterior xiphisternum. There are 21 pairs of ribs, six sternal, ten asternal ribs and the last five being floating ribs.

• 한국식품영양과학회지
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• 제43권3호
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• pp.367-373
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• 2014

본 연구에서는 MG의 RC-58T/h/SA#4 인체 전립선 암세포에 대한 증식 억제 및 apoptosis 유도효과에 대하여 확인하였다. MG는 RC-58T/h/SA#4 세포의 증식을 농도 의존적으로 억제하였다. 이러한 MG에 의한 RC-58T/h/SA#4 세포의 사멸이 apoptosis에 의해 일어나는지를 sub-G1 함량 측정 및 Hoechst 33258 염색을 이용하여 확인하였다. 그 결과 MG를 처리한 군의 sub-G1의 함량이 대조군에 비하여 증가하였으며, methyl gallate를 처리한 군에서 핵의 응축과 apoptotic body 형성을 Hoechst 33258 염색을 통하여 관찰할 수 있었다. 또한 RC-58T/h/SA#4 세포에서 MG가 유도하는 apoptosis의 기전을 확인하기 위하여 다양한 실험을 실시하였다. MG는 DNA의 분절량 증가 및 caspase 활성을 유도하였으며, 활성화된 caspase-8, -9 및 -3에 의해 PARP와 Bid 단백질의 분절을 발현시켰으며, Bcl-2 family 단백질의 발현에 영향을 미쳐 apoptosis를 유도하였음을 확인하였다. 한편 환경호르몬인 dioxin과 bisphenol A를 다양한 농도로 처리한 결과 각각 1 nM, $0.1{\mu}M$ 농도에서 가장 높은 전립선 암세포 과다증식을 유도하였으며, 이를 바탕으로 MG를 농도별로 처리한 결과 환경호르몬에 의해 유도된 인체 전립선 암세포의 증식을 농도 의존적으로 억제시켰다. 본 연구 결과 MG는 RC-58T/h/SA#4 전립선 암세포에서 apoptosis 유도를 통한 암세포 성장 억제효과를 가지고 있음을 확인하였으며, 환경호르몬에 의해 유발될 수 있는 암에 대해서도 유사한 보호효과를 가지고 있음을 증명하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.5705-5711
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• 2013

Background: Embryonic stem cells (ESCs) have the potential to form teratomas when implanted into immunodeficient mice, but data in immunocompetent mice are limited. We therefore investigated teratoma formation after implantation of three different mouse ESC (mESC) lines into immunocompetent mice. Materials and Methods: BALB/c mice were injected with three highly germline competent mESCs (129Sv, BALB/c and C57BL/6) subcutaneously or under the kidney capsule. After 4 weeks, mice were euthanized and examined histologically for teratoma development. The incidence, size and composition of teratomas were compared using Pearson Chi-square, t-test for dependent variables, one-way analysis of variance and the nonparametric Kruskal-Wallis analysis of variance and median test. Results: Teratomas developed from all three cell lines. The incidence of formation was significantly higher under the kidney capsule compared to subcutaneous site and occurred in both allogeneic and syngeneic mice. Overall, the size of teratoma was largest with the 129Sv cell line and under the kidney capsule. Diverse embryonic stem cell-derived tissues, belonging to the three embryonic germ layers, were encountered, reflecting the pluripotency of embryonic stem cells. Most commonly represented tissues were nervous tissue, keratinizing stratified squamous epithelium (ectoderm), smooth muscle, striated muscle, cartilage, bone (mesoderm), and glandular tissue in the form of gut- and respiratory-like epithelia (endoderm). Conclusions: ESCs can form teratomas in immunocompetent mice and, therefore, removal of undifferentiated ESC is a pre-requisite for a safe use of ESC in cell-based therapies. In addition the genetic relationship of the origin of the cell lines to the ability to transplant plays a major role.

• BMB Reports
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• 제34권5호
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• pp.484-488
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• 2001

STATs are proteins with a dual function: signal transducers in the cytoplasm and transcriptional activators in the nucleus. Among the six known major STATs (STAT1-6), STAT3 has been implicated in the widest range of signaling pathways that regulate cell growth and differentiation. As a part of our on-going investigation on the pleiotropic functions of STAT proteins, we examined the role of STAT3 as a molecular adaptor that links diverse cell growth signaling pathways. We observed that STAT3 can be specifically activated by multiple cytokines, such as IL-3, in transformed fibroblasts and IL-4 or IFN-$\gamma$ in primary immune cells, respectively. The selective activation of STAT3 in H-ras-transformed NIH3T3 cells is associated with an increased expression of phosphoserioe STAT3 in these cells, compared to the parental cells. Notably phosphoresine-STAT3 interacts with oncogenic ras, shown by immunoprecipitation and Western blots. The results suggest the role of STAT3 in rasinduced cellular transformation as a molecular adaptor linking the Jak/STAT and Ras/MAPK pathways. In primary immune cells, IL-4 and IFN-$\gamma$ each induced (in addition to the characteristic STAT6 and STAT1 homodimers) the formation of STAT3-containing complexes that bind to GAS probes, which correspond to the $Fe{\varepsilon}$ Rll and $Fe{\gamma}$ RI promoter sequences, respectively. Since IL-4 and IFN-$\gamma$ are known to counter-regulate the expression of these genes, the ability of STAT3 to form heterodimeric complexes with STAT6 or STAT1 implies its role in the fine-tuned control of genes that are regulated by IL-4 and IFN-$\gamma$.