Kim M.G.,National Academy of Agricultural Science |
Kim M.G.,Environmental Biotechnology National Core Research Center
Journal of Plant Biology | Year: 2010
Plants defend themselves by inducing sophisticated multilevel defense responses against pathogenic attack. The first line of defense against microbial pathogens is the process of nonself-recognition, which mediates the activation of the necessary defense repertoire. The hypersensitive response (HR), a macroscopic collapse of plant leaves in primary infection site, is one of such plant resistance responses. Subsequently, the HR triggers a general resistance mechanism called systemic acquired resistance (SAR), rendering uninfected parts of the plants less sensitive to further pathogenic attacks. Here, we show that SIZ1 mutation-mediated preexisting SAR attenuates HR-associated cell death in Arabidopsis thaliana. In siz1 mutant, the amount of PR1 and PR5 stayed high level, and the growth of pathogenic bacteria Pseudomonas syringae pv. maculicola (Pma) strain M6CΔE was reduced. Early callose deposition, spontaneous formation of microscopic cell death, and reactive oxygen species (ROS) were also observed in siz1 mutant. © The Botanical Society of Korea 2009.
Sakkiah S.,Environmental Biotechnology National Core Research Center |
Thangapandian S.,Environmental Biotechnology National Core Research Center |
John S.,Environmental Biotechnology National Core Research Center |
Kwon Y.J.,Kangwon National University |
Lee K.W.,Environmental Biotechnology National Core Research Center
European Journal of Medicinal Chemistry | Year: 2010
Chemical features based 3D pharmacophore models were developed for HSP90 based on the known inhibitors using Discovery Studio V2.1. An optimal pharmacophore model was brought forth and validated using a decoy set, external test set and Fischer's randomization method. The best five features pharmacophore model, Hypo1, includes two hydrogen bond acceptors, three hydrophobic features, which has the highest correlation coefficient (0.93), cost difference (73.88), low RMS (1.24), as well as it shows a high goodness of fit and enrichment factor. Hypo1 was used as a 3D query for virtual screening to retrieve potential inhibitors from Maybridge and Scaffold databases. The hit compounds were subsequently subjected to molecular docking studies and finally, 36 compounds were obtained based on consensus scoring function. © 2010 Elsevier Masson SAS. All rights reserved.
Kwon Y.S.,Gyeongsang National University |
Kwon Y.S.,Environmental Biotechnology National Core Research Center |
Ryu C.-M.,Korea Research Institute of Bioscience and Biotechnology |
Ryu C.-M.,Korean University of Science and Technology |
And 9 more authors.
Planta | Year: 2010
Plant root-associated bacteria (rhizobacteria) elicit plant basal immunity referred to as induced systemic resistance (ISR) against multiple pathogens. Among multi-bacterial determinants involving such ISR, the induction of ISR and promotion of growth by bacterial volatile compounds was previously reported. To exploit global de novo expression of plant proteins by bacterial volatiles, proteomic analysis was performed after exposure of Arabidopsis plants to the rhizobacterium Bacillus subtilis GB03. Ethylene biosynthesis enzymes were significantly up-regulated. Analysis by quantitative reverse transcriptase polymerasechain reaction confirmed that ethylene biosynthesis-related genes SAM-2, ACS4, ACS12, and ACO2 as well as ethylene response genes, ERF1, GST2, and CHIB were up-regulated by the exposure to bacterial volatiles. More interestingly, the emission of bacterial volatiles significantly up-regulated both key defense mechanisms mediated by jasmonic acid and salicylic acid signaling pathways. In addition, high accumulation of antioxidant proteins also provided evidence of decreased sensitivity to reactive oxygen species during the elicitation of ISR by bacterial volatiles. The present results suggest that the proteomic analysis of plant defense responses in bacterial volatile-mediated ISR can reveal the mechanisms of plant basal defenses orchestrated by endogenous ethylene production pathways and the generation of reactive oxygen species. © Springer-Verlag 2010.
Cho W.K.,Environmental Biotechnology National Core Research Center |
Chen X.-Y.,Environmental Biotechnology National Core Research Center |
Rim Y.,Environmental Biotechnology National Core Research Center |
Chu H.,Environmental Biotechnology National Core Research Center |
And 4 more authors.
Journal of Plant Physiology | Year: 2010
The phloem is the major transport route for both small substances and large molecules, such as proteins and RNAs, from their sources to sink tissues. To investigate the proteins present in pumpkin phloem sap, proteome analysis using multidimensional protein identification technology was carried out. Pumpkin phloem peptides obtained by liquid chromatography/mass spectrometry/mass spectrometry were searched against pumpkin protein data derived from the National Center for Biotechnology Information. A total of 47 pumpkin phloem proteins were identified. The identified proteins mainly corresponded to enzymes involved in gibberellin biosynthesis, antioxidation processes, or defense mechanisms. Interestingly, seven enzymes required for gibberellin biosynthesis were identified for the first time by this proteomics approach. In summary, the new phloem proteins identified in this study provide strong evidence for stress and defense signaling and new insights regarding the role of gibberellin in the developmental programming of higher plants through the phloem. © 2010 Elsevier GmbH. All rights reserved.