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Shu-Zhen Zhao Hong-Zhao Sun Ye Gao Na Sui Bao-Shan Wang 《In vitro cellular & developmental biology. Plant》2011,47(3):391-398
Suaeda salsa calluses cultured in darkness for 28 d were transferred to Murashige and Skoog (MS) media containing various growth regulators
under white light conditions for 10 d to investigate cell growth, betacyanin accumulation, and expression of dopa-4,5-dioxygenase
(DODA). Callus growth was markedly promoted when 0.2 mg·L−1 2,4-D and 0.5 mg·L−1 6-BA were added to the MS medium. Surprisingly, of the auxins tested, IAA had no effect on betacyanin content, but 2,4-D
strongly decreased betacyanin content. Betacyanin content was positively correlated with 6-BA concentrations in the range
of 0.1–2.0 mg·L−1. DODA mRNA levels were consistent with the response of betacyanin content to exogenous growth regulators. These results suggest
that betacyanin metabolism in S. salsa calluses is regulated under white light conditions by growth regulators through the regulation of genes such as DODA that are involved in betacyanin synthesis. 相似文献
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Transcriptional programming and functional interactions within the Phytophthora sojae RXLR effector repertoire 总被引:1,自引:0,他引:1
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Carroll JF Tabanca N Kramer M Elejalde NM Wedge DE Bernier UR Coy M Becnel JJ Demirci B Ba?er KH Zhang J Zhang S 《Journal of vector ecology》2011,36(2):258-268
Juniperus communis leaf oil, J. chinensis wood oil, and Cupressus funebris wood oil (Cupressaceae) from China were analyzed by gas chromatography and gas chromatography-mass spectrometry. We identified 104 compounds, representing 66.8-95.5% of the oils. The major components were: α-pinene (27.0%), α-terpinene (14.0%), and linalool (10.9%) for J. communis; cuparene (11.3%) and δ-cadinene (7.8%) for J. chinensis; and α-cedrene (16.9%), cedrol (7.6%), and β-cedrene (5.7%) for C. funebris. The essential oils of C. funebris, J. chinensis, and J. communis were evaluated for repellency against adult yellow fever mosquitoes, Aedes aegypti (L.), host-seeking nymphs of the lone star tick, Amblyomma americanum (L.), and the blacklegged tick, Ixodes scapularis Say, and for toxicity against Ae. aegypti larvae and adults, all in laboratory bioassays. All the oils were repellent to both species of ticks. The EC(95) values of C. funebris, J. communis, and J. chinensis against A. americanum were 0.426, 0.508, and 0.917 mg oil/cm(2) filter paper, respectively, compared to 0.683 mg deet/cm(2) filter paper. All I. scapularis nymphs were repelled by 0.103 mg oil/cm(2) filter paper of C. funebris oil. At 4 h after application, 0.827 mg oil/cm(2) filter paper, C. funebris and J. chinensis oils repelled ≥80% of A. americanum nymphs. The oils of C. funebris and J. chinensis did not prevent female Ae. aegypti from biting at the highest dosage tested (1.500 mg/cm(2) ). However, the oil of J. communis had a Minimum Effective Dosage (estimate of ED(99) ) for repellency of 0.029 ± 0.018 mg/cm(2) ; this oil was nearly as potent as deet. The oil of J. chinensis showed a mild ability to kill Ae. aegypti larvae, at 80 and 100% at 125 and 250 ppm, respectively. 相似文献
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Sui Huang 《BioEssays : news and reviews in molecular, cellular and developmental biology》2013,35(5):414-416
The fateful combination of (i) the Dunning‐Kruger effect (ignorance of one's own ignorance) with (ii) the nonlinear dynamics of the echo‐chamber between reviewers and editors fuels a self‐reinforcing collective delusion system that sometimes spirals uncontrollably away from objectivity and truth. Escape from this subconscious meta‐ignorance is a formidable challenge but if achieved will help correct a central deficit of the peer‐review process that stifles innovation and paradigm shifts. 相似文献
960.
Cheng Wang Gang-Lin Yan Shao-Wu Lü Chun-Hong Sui Yang Zhao Ya-Wei Xu Gang Zhao Jun-jie Xu Ping-Sheng Gong Gui-Min Luo Ying Mu 《Biotechnology and Bioprocess Engineering》2013,18(1):27-34
Glutathione peroxidase (GPX) is one of the important members of the antioxidant enzyme family. It can catalyze the reduction of hydroperoxides with glutathione to protect cells against oxidative damage. Single-chain variable fragment (scFv) can be converted into seleniumcontaining single-chain variable fragment (Se-scFv) by chemical modification of the hydroxyl groups in scFv, thus Se-scFv possesses GPX activity and becomes a prodrug. To improve the expression of scFv and simplify its purification steps, Single-protein production (SPP) system was used to express scFv and chemical modification was used to synthesize Se-scFv. Therefore, we must construct a new scFv-WCD1-lessACA gene, which can express its mRNA not containing any ACA sequences and express its amino acid sequence of target protein (scFv) being same to scFv-WCD1. In this way, the scFv-WCD1-lessACA can be only expressed in SPP system and no other background proteins in the cells could be expressed. The expression results showed that high level of scFv-WCD1-lessACA synthesis was at least sustained for 96 h in the virtual absence of background protein synthesis. Then, selenocysteine (Sec) was incorporated into the scFv-WCD1-lessACA by chemical modification and resulted in Se-scFv-WCD1-lessACA. The enzymatic characteristics of Se-scFv-WCD1-lessACA were determined. GPX activity was 2,563 U/μmol, its binding constant for GSH was 0.687 ×105/mol. Moreover, Se-scFv-WCD1-lessACA was confirmed to have a strong antioxidant ability to protect mitochondria against oxidative damage induced by Vc/Fe2+ (mitochondrial damage model), suggesting that Se-scFv-WCD1-lessACA has potential application for protection of mitochondrial damage induced by reactive oxygen species (ROS). 相似文献