• Journal of Plant Biotechnology
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• 제4권1호
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• pp.1-6
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• 2002

Plants have developed a sophisticated battery of defence responses to protect themselves against attempted pathogen ingress. Manipulation of these defence mechanisms may provide significant opportunities for crop improvement. While plant resistance genes have had a long service history in plant breeding, they possess significant limitations. Recent advances are now providing significant insights into strategies designed to increase the field durability of this class of genes. Hypersensitive cell death is a common feature underlying the deployment of plant defence responses against biographic pathogens. In contrast, necrotrophic pathogens actively kill plant cells. Recently, transgenic plants have been developed that either promote or suppress cell death, providing resistance against either biotrophic or necrotrophic pathogens respectively. Methyl-jasmonate is a key signalling molecule in the establishment of resistance against some fungal pathogens. Increasing the concentration of this molecule in plant cells has been shown to increase resistance against Botrytis cineria, without significantly imparting plant growth or development. Due to the multifarious infection strategies employed by plant pathogens, how-ever, it is unlikely a single commercial product will prove a panacea for global disease control. Future stategies will more likely entail an integrated disease management approach.

• Food Science and Biotechnology
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• 제16권5호
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• pp.747-752
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• 2007

This study was carried out to identify and quantify the flavonoids from 6 different plant parts of Allium victorialis var. platyphyllum (AVP), including the flower, leaf, root, stem, flower stalk, and flower seed, using liquid chromatography/ mass spectrometry. Two major flavonoids were structurally identified as quercetin (3,5,7,3'4,'-pentahydroxyflavone) and kaempferol (3,5,7,4'-tetrahydroxyflavone) at contents of 11.8-25.8 and $6.0-64.4\;{\mu}g/mL$, respectively. In particular, the flower and root plant parts contained the highest amounts of quercetin and kaempferol compared to the other parts. We also assessed the recovery effects of each plant-part extract of AVP on gap junctional intercellular communication (GJIC) in WB-F344 cells by the scrape-loading and dye transfer (SL/DT) method. According to the results, GJIC was reduced by approximately 70.2% ($62.3{\pm}12.5$ cells) compared to the control ($209{\pm}9.5$ cells, 100%) when 12-O-tetradecanoylphorbol-13-acetate (TPA) was treated alone in the WB-F344 rat liver epithelial cells. However, the stem extract (0.2 mg/mL) restored GJIC to basal levels (92%, $204{\pm}2.3$ cells, p<0.01) and the flower extract (0.2 mg/mL) stimulated GJIC to 82.5% ($172.6{\pm}8.3$ cells, p<0.05), when applied together with the TPA.

• Journal of Plant Biology
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• 제34권2호
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• pp.129-136
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• 1991

기주식물 (토끼풀, Trifolium repens L.)의 유조직에 침입하여 생장하는 실새삼(Cuscuta australis R. Brown)의 흡기세포들의 미세구조를 조사하였다. 기주세포들과 직접 접촉되어 있는 흡기의 정면부위는 아직 분지되지 않은 선단세포들 및 이들로부터 분지하여 신장된 세포들(hyphae)로 구성되었다. 이 두 유형의 세포들은 전자밀도가 높은 세포질을 지니며, 또한 핵막이 심하게 만입된 커다란 핵을 갖는 특징을 보였다. 어떤 선단세포에서는 비후된 세포벽 물질이 기주세포벽의 중엽(middle lamellae)으로 침입하고, 파괴된 기주세포의 잔유물을 내포하는 양상을 보였다. 두 유형의 세포들은 원형질막과 세포벽이 안쪽으로 돌출하는 구조를 갖는데, 이는 기주세포들로부터 물질흡수를 촉진하기 위한 표면적의 증가현상으로 해석된다. 기주와 흡기세포의 세포벽사이를 통과하는 원형질연락사는 관찰되지 않았다. 두 식물세포의 경계면에서는 융합된 세포벽을 관찰할 수 있는데, 이 구조는 기주로부터 흡기로의 수분 및 영양물질의 수송 경로로써 작용할 수 있을 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권4호
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• pp.588-595
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• 2013

Mesenchymal stem cells (MSCs) are often known to have a therapeutic potential in the cell-mediated repair for fatal or incurable diseases. In this study, canine umbilical cord MSCs (cUC-MSCs) were isolated from umbilical cord matrix (n = 3) and subjected to proliferative culture for 5 consecutive passages. The cells at each passage were characterized for multipotent MSC properties such as proliferation kinetics, expression patterns of MSC surface markers and self-renewal associated markers, and chondrogenic differentiation. In results, the proliferation of the cells as determined by the cumulative population doubling level was observed at its peak on passage 3 and stopped after passage 5, whereas cell doubling time dramatically increased after passage 4. Expression of MSC surface markers (CD44, CD54, CD61, CD80, CD90 and Flk-1), molecule (HMGA2) and pluripotent markers (sox2, nanog) associated with self-renewal was negatively correlated with the number of passages. However, MSC surface marker (CD105) and pluripotent marker (Oct3/4) decreased with increasing the number of subpassage. cUC-MSCs at passage 1 to 5 underwent chondrogenesis under specific culture conditions, but percentage of chondrogenic differentiation decreased with increasing the number of subpassage. Collectively, the present study suggested that sequential subpassage could affect multipotent properties of cUC-MSCs and needs to be addressed before clinical applications.

• Journal of Ginseng Research
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• 제43권1호
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• pp.95-104
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• 2019

Background: Oxidized low-density lipoprotein (ox-LDL) causes vascular endothelial cell inflammatory response and apoptosis and plays an important role in the development and progression of atherosclerosis. Ginsenoside compound K (CK), a metabolite produced by the hydrolysis of ginsenoside Rb1, possesses strong anti-inflammatory effects. However, whether or not CK protects ox-LDL-damaged endothelial cells and the potential mechanisms have not been elucidated. Methods: In our study, cell viability was tested using a 3-(4, 5-dimethylthiazol-2yl-)-2,5-diphenyl tetrazolium bromide (MTT) assay. Expression levels of interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor-${\alpha}$, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 were determined by enzyme-linked immunosorbent assay and Western blotting. Mitochondrial membrane potential (${\Delta}{\Psi}m$) was detected using JC-1. The cell apoptotic percentage was measured by the Annexin V/ propidium iodide (PI) assay, lactate dehydrogenase, and caspase-3 expression. Apoptosis-related proteins, nuclear factor $(NF)-{\kappa}B$, and mitogen-activated protein kinases (MAPK) signaling pathways protein expression were quantified by Western blotting. Results: Our results demonstrated that CK could ameliorate ox-LDL-induced human umbilical vein endothelial cells (HUVECs) inflammation and apoptosis, $NF-{\kappa}B$ nuclear translocation, and the phosphorylation of p38 and c-Jun N-terminal kinase (JNK). Moreover, anisomycin, an activator of p38 and JNK, significantly abolished the anti-apoptotic effects of CK. Conclusion: These results demonstrate that CK prevents ox-LDL-induced HUVECs inflammation and apoptosis through inhibiting the $NF-{\kappa}B$, p38, and JNK MAPK signaling pathways. Thus, CK is a candidate drug for atherosclerosis treatment.

• 식물조직배양학회지
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• 제25권6호
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• pp.501-505
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• 1998

오이의 국내 F1 품종인 조생낙합의 하배축 유래 배발생 현탁배양 세포의 초저온 보존 시스템을 개발하였다. 액체질소 저장 후 캘러스 재생률은 2M DMNSO와 0.4 M sucrose를 혼용 처리하였을 때 캘러스 재생률이 85%로 가장 높았다. 그러나 glycerol 처리구에서는 처리농도에 상관없이 모든 처리구에서 캘러스 재생이 이루어지지 않았다. 또한 고농도의 삼투용액에서 배양세포의 전처리 과정은 필요하지 않았다. 재생된 캘러스를 1 mg/L 2,4-D가 첨가된 MS 배지로 이식하여 배양하였을 때 다수의 체세포배가 발달하였으며, 체세포배를 MS 기본배지로 옮겨 명배양한 결과 다수의 소식물체가 발달하였다.

• 한국자원식물학회지
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• 제35권2호
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• pp.380-384
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• 2022

본 연구에서 PTS는 지방전구세포에서 PPARγ, C/EBPα 및 FABP4의 발현 억제를 통해 지방전구세포의 adipogenesis를 억제하고, AMPK 및 HSL의 활성화, ATGL의 발현증가, 그리고 perilipin-1의 발현감소를 통해 지방세포의 지질을 분해하여 지방세포 내 과도한 지질형성을 억제하는 것으로 판단된다. 이러한 결과들은 PTS는 비만 예방 및 치료를 위핸잠재적 식의약 소재로의 개발 및 활용이 가능할 것으로 사료된다.

• Journal of Plant Biology
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• 제36권3호
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• pp.285-292
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• 1993

Cellular compatibility in the self-parasitism of Cuscuta australis R. Brown was studied at the ultrastructural level. The front cells of the haustorium penetrated the host stems independently grew within the host tissues and transformed into elongate, filamentous hyphae. Each hyphal cells contained a large nucleus and dense cytoplasm with abundant cell organelles. Multilamellar structures were contained in the cytoplasm and cell walls of the penetrating hyphal cells. When the hyphal cells did not yet invade the host cells, the middle lamella and the fused cellulosic cell walls of the two partners at the host-parasite interface were preserved well. As the invasion of the parasitic hyphal cells progressed, however, the middle lamella was not found at the interface and the host cell walls and plasma membranes were partially broken down. A hyphal cell penetrated deeply into the host cell had a more darkly stained cytoplasm with numerous of cell organelles. In the host cells attacked by the hyphal cells the limiting membranes of plastids were broken down and several vesicles were arrayed near the cell walls. No plasmodesmatal connections between the host and parasite cell walls were found; however, half-plasmodesmata were observed frequently on the side of the hyphal cell walls. These results suggested that the compatibility response in the self-parasitism of Cuscuta was expressed by cell walls, not by plasmodesmata, between the host and the parasite cells.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권2호
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• pp.197-201
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• 2003

The recombinant plasmids harboring a heterologous gene coding mouse endostatin were transfected and expressed stably in Trichoplusia ni Tn 5B1-4 cells and Bombyx mori BmN cells, respectively. Recombinant endostatin expressed in the stably transformed Tn 5B1-4 and BmN cells was secreted into the medium. BmN cells are relatively lower in maximum cell growth and recombinant endostatin production than Tn 5B 1-4 cells. Recombinant endostatin was also purified to homogeneity using a simple one-step ${Ni^2+}$ affinity fractionation method. Purified recombinant endostatin inhibited endothelial cell proliferation in a dose-dependent manner. The concentration at half-maximum inhibition $({ED_50})$ for recombinant endostatin was approximately 0.35 ${\mu}g$/ml.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1993년도 제7회 식물생명공학 심포지움 식물 세포 분화의 분자적 접근 Seventh Symposium on Plant Biotechnology -Approach to Plant Cell Differentiation-
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• pp.149-155
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• 1993