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Manipulation of Catalase Levels Produces Altered Photosynthesis in Transgenic Tobacco Plants 总被引:2,自引:0,他引:2 下载免费PDF全文
Constructs containing the cDNAs encoding the primary leaf catalase in Nicotiana or subunit 1 of cottonseed (Gossypium hirsutum) catalase were introduced in the sense and antisense orientation into the Nicotiana tabacum genome. The N. tabacum leaf cDNA specifically overexpressed CAT-1, the high catalytic form, activity. Antisense constructs reduced leaf catalase specific activities from 0.20 to 0.75 times those of wild type (WT), and overexpression constructs increased catalase specific activities from 1.25 to more than 2.0 times those of WT. The NADH-hydroxypyruvate reductase specific activity in transgenic plants was similar to that in WT. The effect of antisense constructs on photorespiration was studied in transgenic plants by measuring the CO2 compensation point (Γ) at a leaf temperature of 38°C. A significant linear increase was observed in Γ with decreasing catalase (at 50% lower catalase activity Γ increased 39%). There was a significant temperature-dependent linear decrease in Γ in transgenic leaves with elevated catalase compared with WT leaves (at 50% higher catalase Γ decreased 17%). At 29°C, Γ also decreased with increasing catalase in transgenic leaves compared with WT leaves, but the trend was not statistically significant. Rates of dark respiration were the same in WT and transgenic leaves. Thus, photorespiratory losses of CO2 were significantly reduced with increasing catalase activities at 38°C, indicating that the stoichiometry of photorespiratory CO2 formation per glycolate oxidized normally increases at higher temperatures because of enhanced peroxidation. 相似文献
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Activation of a Bean Chitinase Promoter in Transgenic Tobacco Plants by Phytopathogenic Fungi 总被引:7,自引:0,他引:7 下载免费PDF全文
The temporal and spatial expression of a bean chitinase promoter has been investigated in response to fungal attack. Analysis of transgenic tobacco plants containing a chimeric gene composed of a 1.7-kilobase fragment carrying the chitinase 5B gene promoter fused to the coding region of the gus A gene indicated that the chitinase promoter is activated during attack by the fungal pathogens Botrytis cinerea, Rhizoctonia solani, and Sclerotium rolfsii. Although induction of [beta]-glucuronidase activity was observed in tissues that had not been exposed to these phytopathogens, the greatest induction occurred in and around the site of fungal infection. The increase in [beta]-glucuronidase activity closely paralleled the increase in endogenous tobacco chitinase activity produced in response to fungal infection. Thus, the chitinase 5B-gus A fusion gene may be used to analyze the cellular and molecular details of the activation of the host defense system during pathogen attack. 相似文献
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麻疯树curcin启动子的分离及其在转基因烟草中的功能分析 总被引:3,自引:1,他引:3
核糖体失活蛋白是一类可以使核糖体28S rRNA的保守α茎环结构域脱嘌呤的蛋白质。麻疯树毒蛋白(curcin)前体基因编码麻疯树胚乳I型核糖体失活蛋白。从麻疯树基因组中克隆得到其5'侧翼区0.6 kb长的片段,将该片段插入pBI121载体置换其中的CaMV 35S启动子并在相应的转基因烟草中检测报告基因GUS的表达情况。经过GUS活性检测分析发现,该0.6 kb长的片段能够启动报告基因在种子中的表达,并且其在种子不同发育阶段的表达活性存在差异。同时,GUS组织化学染色定位分析表明,在双子叶植物中该启动子片段是胚乳特异性表达的,它从心形胚时期开始持续地在烟草的胚乳中发挥启动活性。 相似文献
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A.-M. Droual J. Creche F. Andreu J.-C. Chenieux M. Rideau S. Hamdi 《Biologia Plantarum》2002,45(3):321-326
The cloning of a 465 bp fragment from the 5-flanking region of the gene encoding a cytosolic cyclophilin from periwinkle was achieved through inverse polymerase chain reaction. The DNA fragment was fused to a gusA-intron marker then introduced into tobacco by Agrobacterium tumefaciens-mediated transformation. Histochemical analysis of the transgenic shoot cultures demonstrated that the construct was able to drive GUS expression in stomata guard cells, but not in mesophyll cells when shoots were still attached to the callus from which they were initiated. In separated transgenic shoots and in seedlings, GUS was expressed in external and internal phloem and root hairs, respectively. GUS activity in transgenic tobacco seedlings was also investigated by fluorimetric assays. Treatments with NaCl or ABA decreased promoter activity whereas treatment with yeast extracts increased it. 相似文献
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核糖体失活蛋白是一类可以使核糖体28S rRNA的保守a茎环结构域脱嘌呤的蛋白质。麻疯树毒蛋白(curcin)前体基因编码麻疯树胚乳I 型核糖体失活蛋白。从麻疯树基因组中克隆得到其5'侧翼区0.6 kb长的片段, 将该片段插入pBI121载体置换其中的CaMV 35S启动子并在相应的转基因烟草中检测报告基因GUS的表达情况。经过GUS活性检测分析发现, 该0.6 kb长的片段能够启动报告基因在种子中的表达, 并且其在种子不同发育阶段的表达活性存在差异。同时, GUS组织化学染色定位分析表明, 在双子叶植物中该启动子片段是胚乳特异性表达的, 它从心形胚时期开始持续地在烟草的胚乳中发挥启动活性。 相似文献
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Mao-Zhi REN Quan-Jia CHEN Li LI Rui ZHANG San-Dui GUO 《植物学报(英文版)》2005,47(10):1254-1259
For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter. These vectors were different only in promoter regions; three truncations of the nodulinlike promoter took the place of the CaMV35S promoter in the pBI121 plant expression vector. Then, the three vectors were introduced into cotton plants via the pollen tube pathway. The expression patterns of the gus gene driven by nodulin-like promoter truncations were investigated in the offspring of transgenic cotton plants. Histochemical GUS staining and fluorescence quantitative analysis were performed to achieve this goal. The results showed that the nodulin-like promoter was a strong, highly reproductive organspecific promoter, which demonstrated a much higher driver activity than the CaMV35S promoter did in cotton reproductive organs, but relatively lower activity in vegetation. Identification of the speciality and strength-determining regions of the nodulin-like promoter was also undertaken. 相似文献
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Hormonal Characterization of Transgenic Tobacco Plants Expressing the rolC Gene of Agrobacterium rhizogenes TL-DNA 总被引:2,自引:0,他引:2 下载免费PDF全文
Transgenic tobacco (Nicotiana tabacum L. cv Wisconsin 38) plants expressing the Agrobacterium rhizogenes rolC gene under the control of the cauliflower mosaic virus 35S RNA promoter were constructed. These plants displayed several morphological alterations reminiscent of changes in indole-3-acetic acid (IAA), cytokinin, and gibberellin (GA) content. However, investigations showed that neither the IAA pool size nor its rate of turnover were altered significantly in the rolC plants. The biggest difference between rolC and wild-type plants was in the concentrations of the cytokinin, isopentenyladenosine (iPA) and the gibberellin GA19. Radio-immunoassay and liquid chromatography-mass spectrometry measurements revealed a drastic reduction in rolC plants of iPA as well as in several other cytokinins tested, suggesting a possible reduction in the synthesis rate of cytokinins. Furthermore, gas chromatography-mass spectrometry quantifications of GA19 showed a 5- to 6-fold increase in rolC plants compared with wild-type plants, indicating a reduced activity of the GA19 oxidase, a proposed regulatory step in the gibberellin biosynthesis. Thus, we conclude that RolC activity in transgenic plants leads to major alterations in the metabolism of cytokinins and gibberellins. 相似文献
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The Promoter of the Gene for Glutamine Synthetase from Rice Shows Organ-Specific and Substrate-Induced Expression in Transgenic Tobacco Plants 总被引:2,自引:0,他引:2
Kozaki Akiko; Sakamoto Atsushi; Tanaka Kunisuke; Takeba Go 《Plant & cell physiology》1991,32(3):353-358
A 2-kb fragment from the 5'-flanking region of the RGS-28 gene,which encodes the cytosolic glutamine synthetase in Oryza sativaL., was fused to a ß-glucuronidase (GUS) reportergene and introduced into Nicotiana tabacum by Agrobacterium-mediatedtransformation. The promoter was predominantly active in theleaves of transgenic plants, as it is in authentic rice plants.The promoter also responded to externally applied ammonium ions.It is suggested that the cis-acting regulatory elements responsiblefor the recognition of the leaf as a site of synthesis and ofammonia, a substrate for glutamine synthetase, are located withina 2-kb region of the promoter. (Received October 15, 1990; Accepted January 11, 1991) 相似文献
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Xiaobo Qin Jinping Zhang Caixia Shao Sha Lin Luding Jiang Shuwen Zhang Ying Xu Fang Chen 《Plant Molecular Biology Reporter》2009,27(3):275-281
Ribosome-inactivating proteins (RIPs) represent those proteins that universally depurinate conserved α-sarcin loops of large
rRNAs. In this study, a 0.6-kb fragment of a 5′ flanking region preceding a curcin gene, encoding a type I RIP curcin, of
Jatropha curcas L. endosperm was cloned, and its regulation of expression of the β-glucuronidase (GUS) reporter gene was investigated in
transgenic tobacco. Analysis of GUS activities showed that the 0.6-kb flanking fragment of the curcin gene was sufficient
to drive the GUS reporter gene expression in tobacco seed. The activity of this flanking fragment was analyzed at different
stages of seed development. Histochemical localization of GUS activity indicated that the promoter was specifically active
in the endosperm tissue of the dicotyledonous tobacco embryo. Moreover, this activity was first initiated at the heart-shaped
embryonic stage during seed development. 相似文献
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Jitka Viktorová Martina Novakova Ladislava Trbolova Blanka Vrchotova Petra Lovecka Martina Mackova 《International journal of phytoremediation》2014,16(9):937-946
Genetically modified plants can serve as an efficient tool for remediation of diverse dangerous pollutants of the environment such as pesticides, heavy metals, explosives and persistent organic compounds. Transgenic lines of Nicotiana tabacum containing bacterial bphC gene from the degradation pathway of polychlorinated biphenyls (PCBs) were tested. The product of the bphC gene – enzyme 2,3-dihydroxybiphenyl-1,2-dioxygenase is responsible for cleaving of the biphenyl ring. The presence of bphC gene in transgenic plants was detected on DNA, RNA and protein level. The expression of the bphC/His gene was verified after purification of the enzyme from plants by affinity chromatography followed by a Western blot and immunochemical assay. The enzyme activity of isolated protein was detected.Efficient transformation of 2,3-DHB by transgenic plants was achieved and the lines also exhibited high production of biomass. The transgenic plants were more tolerant to the commercial PCBs mixture Delor 103 than non-transgenic tobacco. And finally, the higher decrease of total PCB content and especially congener 28 in real contaminated soil from a dumpsite was determined after cultivation of transgenic plant in comparison with non-transgenic tobacco. The substrate specificity of transgenic plants was the same as substrate specificity of BphC enzyme. 相似文献
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Regulation by Cytokinins of Endogenous Levels of Jasmonic and Salicylic Acids in Mechanically Wounded Tobacco Plants 总被引:11,自引:0,他引:11
Sano Hiroshi; Seo Shigemi; Koizumi Nozomu; Niki Tomoya; Iwamura Hajime; Ohashi Yuko 《Plant & cell physiology》1996,37(6):762-769
Plants respond differentially to wounding and pathogens usingdistinct signaling pathways, so that wound signals are transmittedto jasmonic acid (JA) which induces basic pathogenesis-related(PR) proteins, whereas pathogenic signals cause, in additionto JA, accumulation of salicylic acid (SA) which stimulatesproduction of acidic PR proteins. Transgenic tobacco plantsexpressing a gene for a small GTP binding protein respond abnormallyto mechanical wounding to produce SA and consequently acidicPR proteins, suggesting that wound signals cross with pathogensignaling pathways [Sano et al. (1994) Proc. Natl. Acad. Sci.USA 91: 10556]. This unusual signal crossing is associated witha highly sensitive wound-response of transgenic plants which,upon wounding, produce JA at least eighteen hours earlier thanwild-type plants. When wildtype plants are wounded in the presenceof the synthetic cytokinin, benzylaminopurine, production ofJA begins six hours earlier than in untreated samples, and alsoSA begins to accumulate. The cytokinin antagonist, 2-chloro-4-cyclohexylamino-6-ethylamino-s-triazine,erases these effects. Because transgenic plants constitutivelyproduce four-to six-fold higher amounts of endogenous cytokininsthan wild-type plants, it is concluded that cytokinins are indispensablefor control of endogenous levels of SA and JA. (Received April 23, 1996; Accepted June 10, 1996) 相似文献