共查询到20条相似文献，搜索用时 15 毫秒
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Transgenic Brassica compestris L.spp.chinensis plants expressing a choline oxidase(codA) gene from Arthrobacter globiformis were obtained through Agrobacterium tumefaciens-mediated transformation.In the transgenic plants,codA gene expression and its product transportation to chloroplasts were detected by the enzyme-linked immunosorbent assay(ELISA) examination,immunogold localization,and 1 H-nuclear magnetic resonance( 1 H-NMR) . Stress tolerance was evaluated in the T3 plants under extreme temperature and salinity conditions.The plants of transgenic line 1(L1) showed significantly higher net photosynthetic rate(Pn) and Pn recovery rate under high(45°C,4 h) and low temperature(1°C,48 h) treatments,and higher photosynthetic rate under high salinity conditions(100,200,and 300 mmol/L NaCl,respectively) than the wild-type plants.The enhanced tolerance to high temperature and high salinity stresses in transgenic plants is associated with the accumulation of betaine,which is not found in the wild-type plants.Our results indicate that the introduction of codA gene from Arthrobacter globiformis into Brassica compestris L.spp.chinensis could be a potential strategy for improving the plant tolerance to multiple stresses. 相似文献
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Wei-hong Sun Yong Wang Hua-gang He Xue Li Wan Song Bin Du Qing-wei Meng 《Journal of Zhejiang University. Science. B》2013,14(7):578-585
Ascorbate peroxidases are directly involved in reactive oxygen species (ROS) scavenging by reducing hydrogen peroxide to water. The tomato thylakoid-bound ascorbate peroxidase gene (StAPX) was introduced into tobacco. RNA gel blot analysis confirmed that StAPX in tomato leaves was induced by methylviologen-mediated oxidative stress. The sense transgenic seedlings exhibited higher tAPX activity than that of the wild type (WT) plants under oxidative stress conditions, while the antisense seedlings exhibited lower tAPX activity. Lower APX activities of antisense transgenic seedlings caused higher malondialdehyde contents and relative electrical conductivity. The sense transgenic seedlings with higher tAPX activity maintained higher chlorophyll content and showed the importance of tAPX in maintaining the optimal chloroplast development under methylviologen stress conditions, whereas the antisense lines maintained lower chlorophyll content than WT seedlings. Results indicated that the over-expression of StAPX enhanced tolerance to methylviologen-mediated oxidative stress in sense transgenic tobacco early seedlings, whereas the suppression of StAPX in antisense transgenic seedlings showed high sensitivity to oxidative stress. 相似文献
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将含有TaLEA1基因的表达载体pBI121-TaLEA1经根癌农杆菌介导,利用花粉管通道法转入拟南芥,得T0代种子,抗Kan筛选得转基因植株.经PCR检测,初步证明外源TaLEA1基因已整合到拟南芥基因组中. 相似文献
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Li QY Niu HB Yin J Shao HB Niu JS Ren JP Li YC Wang X 《Journal of Zhejiang University. Science. B》2010,11(11):862-870
A transgenic barley line (LSY-11-1-1) with overexpressed Phalaris coerulescens thioredoxin gene (PTrx) was employed to measure the growth, protein oxidation, cell viability, and antioxidase activity in barley roots during germination
on the presence of 2 mmol/L AlCl3 on filter paper. The results show that (1) compared with the non-transgenic barley, LSY-11-1-1 had enhanced root growth,
although both were seriously inhibited after AlCl3 treatment; (2) the degree of protein oxidation and loss of cell viability in roots of LSY-11-1-1 were much less than those
in roots of non-transgenic barley, as reflected by lower contents of protein carbonyl and Evans blue uptakes in LSY-11-1-1;
(3) activities of catalase (CAT), glutathione peroxidase (GPX), ascorbate peroxidase (APX), and glutathione reductase (GR)
in LSY-11-1-1 root tips were generally higher than those in non-transgenic barley root tips, although these antioxidase activities
gave a rise to different degrees in both LSY-11-1-1 and non-transgenic barley under aluminum stress. These results indicate
that overexpressing PTrx could efficiently protect barley roots from oxidative injury by increasing antioxidase activity, thereby quenching ROS caused
by AlCl3 during germination. These properties raise the possibility that transgenic barley with overexpressed PTrx may be used to reduce the aluminum toxicity in acid soils. 相似文献
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The search for active toxins for managing weeds or plant diseases is believed to be a promising avenue of investigation. However,
the effects of Alternaria toxins on insects have just begun to be investigated. Bioactivities of toxins from four strains of Alternaria alternata on Rosa chinensis and rose aphid Macrosiphum rosivorum were tested in the present study. At a concentration of 50.0 μg/ml, the crude extract (toxin) of strain 7484 was found not
to be harmful to rose plants with excised leaf-puncture method (P≥0.079), and rose plants showed enhanced resistance to rose aphids when this Alternaria toxin was sprayed on the plants (P≤0.001). However, this toxin caused no detrimental effects on aphids in insecticidal bioassay at a concentration of 10.0 to
160.0 μg/ml (P≥0.096). Therefore, the Alternaria toxin had significantly induced the resistance of rose plants against rose aphids, demonstrating that the resistance mechanism
triggered by the Alternaria toxin in the rose plant may also be used by the plant to defend itself against insects. Further bioassays aimed to discover
the olfactory responses of aphids to the toxin-induced volatiles of host plants. The aphids were significantly more attracted
to both volatiles emitted and collected from control rose plants than to both volatiles emitted and collected from the toxin-treated
rose plants (P≤0.014). This result showed that the toxin-induced resistance related to the volatile changes of host plants. 相似文献
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Leaf senescence is often caused by water deficit and the chimeric gene PSA612-1PT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance （TBARS） and antioxidant enzymes activities were investigated during leaf senescence of PSA612-1PT modified gerbera induced by osmotic stress compared with the control plant （wild type）. Leaf discs were incubated in 20%, 40% （w/v） polyethylene glycol （PEG） 6 000 nutrient solution for 20 h under continuous light [ 130 μmol/（m^2·s）]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase （SOD）, catalases （CAT）, ascorbate peroxidase （APX）, guaiacol peroxidase （GPX） and dehydroascorbate reductase （DHAR） were stimulated by PEG treatment. However, the increases were higher in PSA612-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation （TBARS content） was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant. It could be concluded that the increases in the activities ofantioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress. 相似文献
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The present study was to test the hypothesis that the plant growth retardants chlorocholine chloride (CCC) and paclobutrazol
(PBZ) could improve the carbohydrate accumulation in lily bulbs by enhancing photosynthetic capacity and changing endogenous
hormones. Plants of Lilium Oriental hybrids ‘Sorbonne’ were treated with a foliar spray of CCC or PBZ (both at 300 mg/L) solution, at six weeks after
planting (6 WAP). The morphological parameters, endogenous hormone contents (gibberellic acid (GA), abscisic acid (ABA), and
indole-3-acetic acid (IAA)), and carbohydrate contents were measured from 6 to 18 WAP, at 2-week intervals. The results showed
that CCC increased the biomass of leaves and stems which might produce more photoassimilates available for transportation
and utilization. However, PBZ treatment suppressed vegetative growth and favored photoassimilate transportation into bulbs.
A slight delay of bud and anthesis formation was observed in both treated plants. CCC and PBZ treatments substantially enhanced
the sucrose contents in leaves probably due to the increase of chlorophyll contents. Treatment with CCC or PBZ decreased GA
but increased IAA contents in lily bulbs which might stimulate starch accumulation and formation of new scales. Our experiment
suggested that CCC or PBZ treatment is an effective method to promote carbohydrate accumulation in lily bulbs. 相似文献
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In this paper, crude monkshood polysaccharide was isolated from Radix Aconiti Lateralis Preparata. The effects of crude monkshood
polysaccharide on Escherichia coli and Staphylococcus aureus were investigated by microcalorimetry. The power-time curves of the bacterial growth at various concentrations (c) of crude monkshood polysaccharide were plotted with a TAM air isothermal microcalorimeter at 37 °C. The growth rate constant
(μ), inhibitory ratio (I), peak-height (P
m), and peak-time (t
m) were calculated. From the data, the relationship between μ and c also was established. The growth rate constant μ decreased with the increasing concentrations of crude monkshood polysaccharide.
Moreover, P
m reduced and t
m increased with increasing concentrations. The experimental results revealed that crude monkshood polysaccharide had inhibitory
activity towards S. aureus and E. coli. Results obtained from our study strongly suggest that microcalorimetry is a fast, simple, and more sensitive technology
that can be easily performed to study the effect of drugs on bacteria. 相似文献
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Zhao YE Peng Y Wang XL Wu LP Wang M Yan HL Xiao SX 《Journal of Zhejiang University. Science. B》2011,12(12):1008-1015
Demodex has been considered to be related with multiple skin disorders, but controversy persists. In this case-control study, a survey
was conducted with 860 dermatosis patients aged 12 to 84 years in Xi’an, China to identify the association between facial
dermatosis and Demodex. Amongst the patients, 539 suffered from facial dermatosis and 321 suffered from non-facial dermatosis. Demodex mites were sampled and examined using the skin pressurization method. Multivariate regression analysis was applied to analyze
the association between facial dermatosis and Demodex infestation, and to identify the risk factors of Demodex infestation. The results showed that total detection rate of Demodex was 43.0%. Patients aged above 30 years had higher odds of Demodex infestation than those under 30 years. Compared to patients with neutral skin, patients with mixed, oily, or dry skin were
more likely to be infested with Demodex (odds ratios (ORs) were 2.5, 2.4, and 1.6, respectively). Moreover, Demodex infestation was found to be statistically associated with rosacea (OR=8.1), steroid-induced dermatitis (OR=2.7), seborrheic
dermatitis (OR=2.2), and primary irritation dermatitis (OR=2.1). In particular, ORs calculated from the severe infestation
(≥5 mites/cm2) rate were significantly higher than those of the total rate. Therefore, we concluded that Demodex is associated with rosacea, steroid-induced dermatitis, seborrheic dermatitis, and primary irritation dermatitis. The rate
of severe infestation is found to be more correlated with various dermatosis than the total infestation rate. The risk factors
of Demodex infestation, age, and skin types were identified. Our study also suggested that good hygiene practice might reduce the chances
of demodicosis and Demodex infestation. 相似文献
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根据物种间同源基因相对保守的特点,利用生物信息学的方法,以大豆液泡膜H+-ATPase A亚基基因cDNA序列为信息探针,通过电子克隆得到了蒺藜苜蓿液泡膜H+-ATPase A亚基cDNA,命名为MtVHA-A。该cD-NA长2750bp,其中含5’非翻译区220bp,开放阅读框1875bp,3’非翻译区655bp,其推断的编码产物由624个氨基酸组成,理论分子量为69kDa,与蜜柑、番茄、拟南芥、棉花等植物中液泡膜H+-ATPase A亚基氨基酸序列同源性高达90%以上,且有很高的功能区段保守性。 相似文献
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Yan-hong ZHOU Yi-li ZHANG Xue-min WANG Jin-xia CUI Xiao-jian XIA Kai SHI Jing-quan YU 《Journal of Zhejiang University. Science. B》2011,12(2):126-134
Cucumber and rice plants with varying ammonium (NH4
+) sensitivities were used to examine the effects of different nitrogen (N) sources on gas exchange, chlorophyll (Chl) fluorescence
quenching, and photosynthetic electron allocation. Compared to nitrate (NO3
−)-grown plants, cucumber plants grown under NH4
+-nutrition showed decreased plant growth, net photosynthetic rate, stomatal conductance, intercellular carbon dioxide (CO2) level, transpiration rate, maximum photochemical efficiency of photosystem II, and O2-independent alternative electron flux, and increased O2-dependent alternative electron flux. However, the N source had little effect on gas exchange, Chl a fluorescence parameters, and photosynthetic electron allocation in rice plants, except that NH4
+-grown plants had a higher O2-independent alternative electron flux than NO3
−-grown plants. NO3
− reduction activity was rarely detected in leaves of NH4
+-grown cucumber plants, but was high in NH4
+-grown rice plants. These results demonstrate that significant amounts of photosynthetic electron transport were coupled to
NO3
− assimilation, an effect more significant in NO3
−-grown plants than in NH4
+-grown plants. Meanwhile, NH4
+-tolerant plants exhibited a higher demand for the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) for
NO3
− reduction, regardless of the N form supplied, while NH4
+-sensitive plants had a high water-water cycle activity when NH4
+ was supplied as the sole N source. 相似文献
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根据物种间同源基因相对保守的特点,利用生物信息学的方法,以大豆液泡膜H^＋-ATPaseA亚基基因cDNA序列为信息探针,通过电子克隆得到了蒺藜苜蓿液泡膜H^＋-ATPaseA亚基cDNA,命名为MtVHA-A。该cDNA长2750bp,其中含5’非翻译区220bp,开放阅读框1875bp,3’非翻译区655bp,其推断的编码产物由624个氨基酸组成,理论分子量为69kDa,与蜜柑、番茄、拟南芥、棉花等植物中液泡膜H^＋-ATPaseA亚基氨基酸序列同源性高达90％以上,且有很高的功能区段保守性。 相似文献
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Prapassorn Bussaman Chirayu Sa-Uth Paweena Rattanasena Angsumarn Chandrapatya 《Journal of Zhejiang University. Science. B》2012,13(4):261-266
Xenorhabdus bacterium has been used as a biological control agent against Luciaphorus sp., a mushroom mite endemic in Thailand. To develop an effective formulation of Xenorhabdus stokiae, treatments using different parts of X. stokiae isolate PB09 culture, including whole cell suspension, cell-free supernatant, and crude cell extract, were performed. The
results show that different parts of X. stokiae isolate PB09 culture could induce variable effects on mite mortality and fecundity. Application with cell-free supernatant
of X. stokiae culture resulted in both the highest mite mortality rate [(89.00±3.60)%] and the lowest mite fecundity [(41.33±23.69) eggs/gravid
female]. Whole cell suspension of X. stokiae isolate PB09 culture was found to be slightly less effective than its cell-free supernatant, suggesting that X. stokiae was more likely to release its metabolites with acaricidal activities to the surrounding culture media. Crude cell extract
of X. stokiae was not effective against mites. Cell-free supernatant of X. stokiae isolate PB09 was the most effective biological control agent and it could be conveniently used in future formulations instead
of live bacteria. 相似文献
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The AtTOM1 gene of Arabidopsis thaliana had been shown to be essential for the efficient multiplication of Tobacco mosaic virus(TMV) in A.thaliana.In this study,we cloned an AtTOM1-like gene from Nicotiana benthamiana named as NbTOM1.Sequence alignment showed that NbTOM1 is closely related to AtTOM1 homologues of N.tabacum and Lycopersicon esculentum with 97.2% and 92.6% nucleotide sequence identities,respectively.Silencing of NbTOM1 by a modified viral satellite DNA-based vector resulted in complete inhibition of the multiplication of TMV in N.benthamiana.The result suggests that inhibition of NbTOM1 via RNA silencing is a potentially useful method for generating TMV-resistant plants. 相似文献