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In conifers, the cytochrome P450 monooxygenase of the CYP720B family plays an important role in the synthesis of diterpene resin acids, which are specialised metabolites of the oleoresin defence. We isolated CYP720B19 from Pinus armandi and found that it belongs to the CYP720B family. The CYP720B19 open reading frame of 1467 bp encodes a protein of 488 amino acid residues with high similarity to abietadienol/abietadienal oxidase. Differential expression of the CYP720B19 gene significantly changed when plants were inoculated with the fungus Leptographium qinlingensis, mechanically wounded, or treated with methyl jasmonate (MeJa) and Tween at 4 days and 8 days. Increased expression of the CYP720B19 gene after these treatments suggested that the gene was involved in pine defence against inoculation by L. qinlingensis, MeJa treatment and mechanical injury. 相似文献
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Michael A. Hardigan Emily Crisovan John P. Hamilton Jeongwoon Kim Parker Laimbeer Courtney P. Leisner Norma C. Manrique-Carpintero Linsey Newton Gina M. Pham Brieanne Vaillancourt Xueming Yang Zixian Zeng David S. Douches Jiming Jiang Richard E. Veilleux C. Robin Buell 《The Plant cell》2016,28(2):388-405
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Tran Cuong Manh Van Pham Hai Nguyen Hien Thuy Nguyen Thuy Thi Vu Lam Dinh Do Tung Hoang 《Plasmonics (Norwell, Mass.)》2019,14(6):1587-1592
Plasmonics - Since the metamaterial perfect absorber (MPA) is composed of electromagnetic resonance structures, the main operational mechanism of the MPA is electromagnetic resonance. In this work,... 相似文献
125.
Duc Khanh Le Quang Khai Le Thi Thuy Hang Tran Duc Viet Nguyen Thi Hang Dao Thi Thuy Nguyen Xuan Lam Truong Quang Cuong Nguyen Huy Phong Pham Thi Thu Thuy Phan Gajendra Babu Baktavachalam 《Journal of Asia》2019,22(2):493-498
Susceptibility of Asian corn borer (ACB), Ostrinia furnacalis (Guenée) to Bacillus thuringiensis (Bt) Cry1Ab protein was studied between 2015 and 2016 with 11 ACB populations, collected from various geographical regions in Vietnam. A concentration range of Cry1Ab from 0.20 to 26.10 ng/cm2 of diet was evaluated against F1 ACB neonates using diet surface-overlay bioassays. Mortality data was recorded daily until seven days after infestation. Growth inhibition was recorded at the end of seven days. The median lethal concentration (LC50) varied ≈3-fold among the different populations, ranging from 0.58 to 1.83 ng/cm2 of diet with an overall mean of 0.86 ng/cm2 of diet. Even the lowest concentration of 0.20 ng/cm2 caused 73.53% growth inhibition. >90% growth inhibition was achieved at 0.82 ng/cm2 or higher concentrations. The results reflect natural variation in Bt susceptibility among ACB populations rather than variation caused by prior exposure to selection pressures. LC99 value (17.26 ng/cm2) was generated by pooling mortality data across different populations. The upper fiducial limit of LC99 (24.38 ng/cm2) could be a potential diagnostic dose for future resistance monitoring programs. The findings from this study suggest that ACB populations in Vietnam are highly susceptible to Cry1Ab protein. This is the first report of Cry1Ab susceptibility of different ACB populations in Vietnam and will serve as a baseline for future resistance monitoring work. 相似文献
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Tsikas D Thum T Becker T Pham VV Chobanyan K Mitschke A Beckmann B Gutzki FM Bauersachs J Stichtenoth DO 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,851(1-2):229-239
Dimethylamine [DMA, (CH(3))(2)NH)] is abundantly present in human urine. Main sources of urinary DMA have been reported to include trimethylamine N-oxide, a common food component, and asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis. ADMA is excreted in the urine in part unmetabolized and in part after hydrolysis to DMA by dimethylarginine dimethylaminohydrolase (DDAH). Here we describe a GC-MS method for the accurate and rapid quantification of DMA in human urine. The method involves use of (CD(3))(2)NH as internal standard, simultaneous derivatization with pentafluorobenzoyl chloride and extraction in toluene, and selected-ion monitoring of m/z 239 for DMA and m/z 245 for (CD(3))(2)NH in the electron ionization mode. GC-MS analysis of urine samples from 10 healthy volunteers revealed a DMA concentration of 264+/-173 microM equivalent to 10.1+/-1.64 micromol/mmol creatinine. GC-tandem MS analysis of the same urine samples revealed an ADMA concentration of 27.3+/-15.3 microM corresponding to 1.35+/-1.2 micromol/mmol creatinine. In these volunteers, a positive correlation (R=0.83919, P=0.0024) was found between urinary DMA and ADMA, with the DMA/ADMA molar ratio being 10.8+/-6.2. Elevated excretion rates of DMA (52.9+/-18.5 micromol/mmol creatinine) and ADMA (3.85+/-1.65 micromol/mmol creatinine) were found by the method in 49 patients suffering from coronary artery disease, with the DMA/ADMA molar ratio also being elevated (16.8+/-12.8). In 12 patients suffering from end-stage liver disease, excretion rates of DMA (47.8+/-19.7 micromol/mmol creatinine) and ADMA (5.6+/-1.5 micromol/mmol creatinine) were found to be elevated, with the DMA/ADMA molar ratio (9.17+/-4.2) being insignificantly lower (P=0.46). Between urinary DMA and ADMA there was a positive correlation (R=0.6655, P<0.0001) in coronary artery disease, but no correlation (R=0.27339) was found in end-stage liver disease. 相似文献
129.
Beno?t J Smagghe Anne-Sophie Blervacq Christelle Blassiau Jean-Pierre Decottignies Jean-Pierre Jacquot Mark S Hargrove Jean-Louis Hilbert 《Plant signaling & behavior》2007,2(1):43-49
Hemoglobins are ancient O2-binding proteins, ubiquitously found in eukaryotes. They have been categorized as symbiotic, nonsymbiotic and truncated hemoglobins. We have investigated the cellular localization of nonsymbiotic hemoglobin proteins during somatic embryogenesis in Cichorium hybrid leaves (Cichorium intybus L. var. sativum × C. endivia var. latifolia) using immunolocalization technique. These proteins were detected during the two steps of culture: induction and expression. In leaves, hemoglobins colocalised with plastids, which were dispersed in the parietal cytoplasm as well as in the two guard cells of a stomata, but not in epidermis cells. Upon induction of embryogenesis, in the dark, this pattern disappeared. During the induction phase, where competent cells reinitiate the cell cycle and prepare for mitosis, hemoglobins appeared initially near chloroplasts, and then in the vicinity of vascular vessels especially in the phloem and in cells surrounding the xylem vessels. When leaf fragments were transferred to another medium for the expression phase, hemoglobins were observed in the majority of the leaf blade cells and in small young embryos but not in the older ones. Hemoglobins were also detected in other leaves cells or tissues all along the process. The role of these nonsymbiotic hemoglobins during somatic embryogenesis is discussed.Key Words: chicory, immunolocalization, nonsymbiotic hemoglobin, somatic embryogenesis 相似文献