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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
3.
陈玉芹 《唐山师范学院学报》2001,23(5):12-14
对三系法和二系法杂交育种进行了比较。结果表明，三系法是一种行之有效的传统育种方法，但它必须要三系（不育系，保持系，恢复系）配套，增加了育种的时间和资金；而二系法选用光敏核不育系的自交不育系做母本，用加显性标记基因的恢复系作父本，省去了繁殖保持系的工作，同时，这种不育系会因光照长度或温度高低（或两者兼有）而在可育与不育之间互相转换，而这些条件都可以人为控制，这既保证了杂种优势的利用，又节省了资金，是一种具有广阔前景的育种方法。 相似文献
4.
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
5.
M. Aminur Rahman Tsuyoshi Uehara Aziz Arshad Fatimah Md. Yusoff Mariana Nor Shamsudin 《Journal of Zhejiang University. Science. B》2012,13(10):797-810
Two reef margin species of tropical sea urchins, Echinometra sp. C (Ec) and Echinometra oblonga (Eo), occur sympatrically on Okinawa intertidal reefs in southern Japan. Hybridization between these species was examined through a series of cross-fertilization experiments. At limited sperm concentrations, where conspecific crosses reached near 100% fertilization, both heterospecific crosses showed high fertilization rates (81%–85%). The compatibility of the gametes demonstrated that if gamete recognition molecules are involved in fertilization of these species, they are not strongly species-specific. We found that conspecific crosses reached peak fertilization levels much faster than did heterospecific crosses, indicating the presence of a prezygotic barrier to hybridization in the gametes. Larval survival, metamorphosis, and juvenile and adult survival of hybrid groups were nearly identical to those of their parent species. Hybrids from crosses in both directions developed normally through larval stages to sexually mature adults, indicating that neither gametic incompatibility nor hybrid inviability appeared to maintain reproductive isolation between these species. In adults, Ec×Ec crosses gave the highest live weight, followed by Eo (ova)×Ec (sperm), Ec (ova)×Eo (sperm), and Eo×Eo. Other growth performance measures (viz., test size, Aristotle’s lantern length, and gonad index) of hybrid groups and their parental siblings showed the same trends. The phenotypic color patterns of the hybrids were closer to the maternal coloration, whereas spine length, tube-foot and gonad spicule characteristics, pedicellaria valve length, and gamete sizes showed intermediate features. Adult F1 hybrids were completely fertile and displayed high fertilization success in F1 backcrosses, eliminating the likelihood that hybrid sterility is a postzygotic mechanism of reproductive isolation. Conversely, intensive surveys failed to find hybrid individuals in the field, suggesting the lack or rarity of natural hybridization. This strongly suggests that reproductive isolation is achieved by prezygotic isolating mechanism(s). Of these mechanisms, habitat segregation, gamete competition, differences in spawning times, gametic incompatibility or other genetic and non-genetic factors appear to be important in maintaining the integrity of these species. 相似文献
6.
Jun-jie Ye Li Ma Li-juan Yang Jin-huan Wang Yue-li Wang Hai Guo Ning Gong Wen-hui Nie Shu-hua Zhao 《Journal of Zhejiang University. Science. B》2013,14(9):807-815
Objective: There are many reports on associations between spermatogenesis and partial azoospermia factor c (AZFc) deletions as well as duplications; however, results are conflicting, possibly due to differences in methodology and ethnic background. The purpose of this study is to investigate the association of AZFc polymorphisms and male infertility in the Yi ethnic population, residents within Yunnan Province, China. Methods: A total of 224 infertile patients and 153 fertile subjects were selected in the Yi ethnic population. The study was performed by sequence-tagged site plus/minus (STS+/−) analysis followed by gene dosage and gene copy definition analysis. Y haplotypes of 215 cases and 115 controls were defined by 12 binary markers using single nucleotide polymorphism on Y chromosome (Y-SNP) multiplex assays based on single base primer extension technology. Results: The distribution of Y haplotypes was not significantly different between the case and control groups. The frequencies of both gr/gr (7.6% vs. 8.5%) and b2/b3 (6.3% vs. 8.5%) deletions do not show significant differences. Similarly, single nucleotide variant (SNV) analysis shows no significant difference of gene copy definition between the cases and controls. However, the frequency of partial duplications in the infertile group (4.0%) is significantly higher than that in the control group (0.7%). Further, we found a case with sY1206 deletion which had two CDY1 copies but removed half of DAZ genes. Conclusions: Our results show that male infertility is associated with partial AZFc duplications, but neither gr/gr nor b2/b3 deletions, suggesting that partial AZFc duplications rather than deletions are risk factors for male infertility in Chinese-Yi population. 相似文献
7.
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
8.
Jia-wei LOU Li ZHU Mian-bin WU Li-rong YANG Jian-ping LIN Pei-lin CEN 《Journal of Zhejiang University. Science. B》2014,15(5):491-499
The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS), was expressed in Escherichia coli Rosetta (DE3) and the enzymatic properties of the purified recombinant ALAS (RC-ALAS) were studied. Compared with ALASs encoded by hemA genes from Agrobacterium radiobacter (AR-ALAS) and Rhodobacter sphaeroides (RS-ALAS), the specific activity of RC-ALAS reached 198.2 U/mg, which was about 31.2% and 69.5% higher than those of AR-ALAS (151.1 U/mg) and RS-ALAS (116.9 U/mg), respectively. The optimum pH values and temperatures of the three above mentioned enzymes were all pH 7.5 and 37 °C, respectively. Moreover, RC-ALAS was more sensitive to pH, while the other two were sensitive to temperature. The effects of metals, ethylene diamine tetraacetic acid (EDTA), and sodium dodecyl sulfate (SDS) on the three ALASs were also investigated. The results indicate that they had the same effects on the activities of the three ALASs. SDS and metal ions such as Co2+, Zn2+, and Cu2+ strongly inhibited the activities of the ALASs, while Mn2+ exerted slight inhibition, and K+, Ca2+, Ba2+, Mg2+, or EDTA had no significant effect. The specificity constant of succinyl coenzyme A [(k cat/K m)S-CoA] of RC-ALAS was 1.4989, which was higher than those of AR-ALAS (0.7456) and RS-ALAS (1.1699), showing its high catalytic efficiency. The fed-batch fermentation was conducted using the recombinant strain containing the R. capsulatus hemA gene, and the yield of 5-aminolevulinic acid (ALA) achieved was 8.8 g/L (67 mmol/L) under the appropriate conditions. 相似文献
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Ya-wei Li Ze-hua Gong Yao Mu Yi-xian Zhang Zeng-jie Qiao Li-ping Zhang Zhu-ping Jin Hua Li Yan-xi Pei 《Journal of Zhejiang University. Science. B》2012,13(12):1006-1014
The gene AtCSR encodes peptidyl-prolyl cis/trans isomerases (PPIases) that accelerate energetically unfavorable cis/trans isomerization of the peptide bond preceding proline production.In our studies,we found that AtCSR was associated with cadmium (Cd)-sensitive response in Arabidopsis.Our results show that AtCSR expression was triggered by Cd-stress in wild type Arabidopsis.The expression of some genes responsible for Cd2+ transportation into vacuoles was induced,and the expression of the iron-regulated transporter 1 (IRT1) related to Cd2+ absorption from the environment was not induced in wild type with Cd2+ treatment.The expression of Cd-transportation related genes was not in response to Cd-stress,whereas IRT expression increased dramatically in atcsr-2 with Cd2+ treatment.The expression of glutathione 1 (GSH1) was consistent with GSH being much lower in atcsr-2 in comparison with the wild type with Cd2+ treatment.Additionally,malondialdehyde (MDA),hydrogen peroxide,and Cd2+ contents,and activities of some antioxidative enzymes,differed between the wild type and atcsr-2.Hydrogen sulfide (H2S) has been confirmed as the third gas-transmitter over recent years.The findings revealed that the expression pattern of H2 S-releasing related genes and that of Cd-induced chelation and transportation genes matched well in the wild type and atcsr-2,and H2S could regulate the expression of the Cd-induced genes and alleviate Cd-triggered toxicity.Finally,one possible suggestion was given:down-regulation of atcsr-2,depending on H2S gas-transmitter not only weakened Cd2+ chelation,but also reduced Cd2+ transportation into vacuoles,as well as enhancing the Cd2+ assimilation,thus rendering atcsr-2 mutant sensitive to Cd-stress. 相似文献
10.
为了将玉米A型胞质不育准确归群,从分析A型不育系育性基因型入手,结合恢复性的遗传和小斑病的自然感染进行综合研究。采用启行设计的A型与T、S、C三类群的不育系(保持系)的互测杂交试验,初证出A型不育系的育性基因位点及对数;并用多型恢复进行辅助签定;14个自交系与A型不育系的杂交F_2代育性反应分别呈3∶1和9∶7,符合T型恢复性的遗传规律;最后再结合A型细胞质受小斑病感染的事实,初步将A型归入T群,试验结果表明,通过明确育性基因互位点上,有助于分析特定自交系测交育性反应的疑异和胞质不育的分类。 相似文献
11.
Na Wang Cai-ying Jiang Ming-xing Jiang Chuan-xi Zhang Jia-an Cheng 《Journal of Zhejiang University. Science. B》2010,11(9):728-734
The piggyBac transposon has been long used to integrate foreign DNA into insect genomes. However, undesirable transgene expression can
result from random insertions into the genome. In this study, the efficiency of chimeric Gal4-piggyBac transposase in directing integration onto a DNA target plasmid was evaluated in cultured silkworm Bombyx mori Bm-12 and fruit fly Drosophila Schneider 2 (S2) cells. The Gal4-piggyBac transposase has a Gal4 DNA-binding domain (DBD), and the target plasmid has upstream activating sequences (UAS) to which
the Gal4 DBD can bind with high affinity. The results indicate that, in the Bm-12 and S2 cells, transpositional activity of
Gal4-piggyBac transposase was increased by 4.0 and 7.5 times, respectively, compared to controls, where Gal4-UAS interaction was absent.
Moreover, the Gal4-piggyBac transposase had the ability of directing piggyBac element integration to certain sites of the target plasmid, although the target-directing specificity was not as high as
expected. The chimeric piggyBac transposase has the potential for use in site-directed transgenesis and gene function research in B. mori. 相似文献
12.
Insertion mutagenesis has become one of the most popular methods for gene functions analysis. Here we report a two-elementAc/Ds transposon system containing enhancer trap and gene trap for gene tagging in rice. The excision ofDs element was examined by PCR amplification. The excision frequency ofDs element varied from 0% to 40% among 20 F2 populations derived from 11 differentDs parents. Southern blot analysis revealed that more than 70% of excisedDs elements reinserted into rice genome and above 70% of the reinsertedDs elements were located at different positions of the chromosome in rice. The result of histochemical GUS analysis indicated
that 28% of enhancer trap and 22% of gene trap tagging plants displayed GUS activity in leaves, roots, flowers or seeds. The
GUS positive lines will be useful for identifying gene function in rice.
Project supported by the Hi-Tech Research and Development Program (863) of China (No. 2002AA2Z1003) 相似文献
13.
Yan-bin Shi Lian Liu Wei Shao Ting Wei Gui-mei Lin 《Journal of Zhejiang University. Science. B》2015,16(8):690-695
The metabolic activity of organisms can be measured by recording the heat output using microcalorimetry. In this paper, the total alkaloids in the traditional Chinese medicine Radix Aconiti Lateralis were extracted and applied to Escherichia coli and Staphylococcus aureus. The effect of alkaloids on bacteria growth was studied by microcalorimetry. The power-time curves were plotted with a thermal activity monitor (TAM) air isothermal microcalorimeter and parameters such as growth rate constant (μ), peak-time (Tm), inhibitory ratio (I), and enhancement ratio (E) were calculated. The relationships between the concentration of Aconitum alkaloids and μ of E. coli or S. aureus were discussed. The results showed that Aconitum alkaloids had little effect on E. coli and had a potentially inhibitory effect on the growth of S. aureus. 相似文献
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Jia Y Tang SR Ju XH Shu LN Tu SX Feng RW Giusti L 《Journal of Zhejiang University. Science. B》2011,12(4):313-325
This study was conducted to investigate the combined effects of elevated CO2 levels and cadmium (Cd) on the root morphological traits and Cd accumulation in Lolium multiflorum Lam. and Lolium perenne L. exposed to two CO2 levels (360 and 1 000 μl/L) and three Cd levels (0, 4, and 16 mg/L) under hydroponic conditions. The results show that elevated
levels of CO2 increased shoot biomass more, compared to root biomass, but decreased Cd concentrations in all plant tissues. Cd exposure
caused toxicity to both Lolium species, as shown by the restrictions of the root morphological parameters including root length, surface area, volume, and
tip numbers. These parameters were significantly higher under elevated levels of CO2 than under ambient CO2, especially for the number of fine roots. The increases in magnitudes of those parameters triggered by elevated levels of
CO2 under Cd stress were more than those under non-Cd stress, suggesting an ameliorated Cd stress under elevated levels of CO2. The total Cd uptake per pot, calculated on the basis of biomass, was significantly greater under elevated levels of CO2 than under ambient CO2. Ameliorated Cd toxicity, decreased Cd concentration, and altered root morphological traits in both Lolium species under elevated levels of CO2 may have implications in food safety and phytoremediation. 相似文献
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Wang LR Zhang GB Chen J Li J Li MW Xu N Wang Y Shen Tu JZ 《Journal of Zhejiang University. Science. B》2011,12(3):174-179
Objective
To evaluate the predictive values of gene expressions of ribonucleotide reductase M1 (RRM1) and breast cancer susceptibility gene 1 (BRCA1) in peripheral blood from Chinese patients with non-small-cell lung cancer (NSCLC) treated with gemcitabine plus platinum. 相似文献18.
Rao AQ Irfan M Saleem Z Nasir IA Riazuddin S Husnain T 《Journal of Zhejiang University. Science. B》2011,12(4):326-334
The phytochrome B (PHYB) gene of Arabidopsis thaliana was introduced into cotton through Agrobacterium tumefaciens. Integration and expression of PHYB gene in cotton plants were confirmed by molecular evidence. Messenger RNA (mRNA) expression in one of the transgenic lines,
QCC11, was much higher than those of control and other transgenic lines. Transgenic cotton plants showed more than a two-fold
increase in photosynthetic rate and more than a four-fold increase in transpiration rate and stomatal conductance. The increase
in photosynthetic rate led to a 46% increase in relative growth rate and an 18% increase in net assimilation rate. Data recorded
up to two generations, both in the greenhouse and in the field, revealed that overexpression of Arabidopsis thaliana PHYB gene in transgenic cotton plants resulted in an increase in the production of cotton by improving the cotton plant growth,
with 35% more yield. Moreover, the presence of the Arabidopsis thaliana PHYB gene caused pleiotropic effects like semi-dwarfism, decrease in apical dominance, and increase in boll size. 相似文献
19.
Objective
The gene for mast cell chymase (CMA1) is an ideal candidate for investigating the genetic predisposition to coronary heart disease (CHD), as activated mast cells have been found to be present in a greater proportion in the shoulder region of atheroma than in normal coronary intimae. Previous studies have indicated that CMA1 promoter polymorphism rs1800875 may be involved in regulating immunoglobulin E (IgE) levels in patients with eczema, and it is associated with the progression of immunoglobulin A nephropathy. 相似文献20.
Ammonium (NH4
+) is an important form of nitrogen nutrient for most plants, yet is also a stressor for many of them. However, the primary
events of NH4
+ toxicity at the cellular level are still unclear. Here, we showed that NH4
+ toxicity can induce the root cell death in a temporal pattern which primarily occurs in the cells of root maturation and
elongation zones, and then spreads to the cells in the meristem and root cap. The results from the NH4
+-hypersensitive mutant hsn1 further confirmed our findings. Taken together, NH4
+ toxicity inhibits primary root growth by inhibiting cell elongation and division and inducing root cell death. 相似文献