After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resist...After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene. Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin. Under continuous selection, hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons. The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR (polymerase chain reaction) for the intron-gus gene and by Southern hybridization of the hph gene. GUS enzyme activity was detected in leaflets from transgenic plants but not from control, non-transformed plants. The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.展开更多
Stress associated proteins（SAPs） are the A20/AN1 zinc-finger proteins which confer to abiotic stresses in plants. In this study, TaSAP7-B, including two AN1 domains, was isolated from B genome of wheat（Triticum aes...Stress associated proteins（SAPs） are the A20/AN1 zinc-finger proteins which confer to abiotic stresses in plants. In this study, TaSAP7-B, including two AN1 domains, was isolated from B genome of wheat（Triticum aestivum L.）. Sequencing analysis on TaSAP7-B illustrated one In Del（insertion-deletion） and one SNP（single nucleotide polymorphism） in the promoter region while no diversity was observed in the coding region. On the basis of SNP in the promoter region（–260 bp）, a dCAPS（derived cleaved amplified polymorphic sequences） marker SNP-260 was developed for TaSAP7-B. Using a natural population consisting of 262 wheat accessions, significant associations were detected between the marker SNP-260 and agronomic traits, such as plant height（PH）, peduncle length（PL）, length of penultimate internode（LPI）, number of spike per plant（NSP）, and 1 000-grain weight（TGW）. Two genotypes were identified using marker SNP-260 in the natural population. Among them, the genotypes possessing C allele exhibited a higher TGW and shorter PH than the T genotypes. Hence, base C was considered as the superior allele. The dCAPS marker of TaSAP7-B can be instrumental for marker-assisted selection for high grain size and short plant height.展开更多
More than 50%of the world population is infected with Helicobacter pylori(H.pylori).The bacterium highly links to peptic ulcer diseases and duodenal ulcer,which was classified as a groupⅠcarcinogen in 1994 by the WHO...More than 50%of the world population is infected with Helicobacter pylori(H.pylori).The bacterium highly links to peptic ulcer diseases and duodenal ulcer,which was classified as a groupⅠcarcinogen in 1994 by the WHO.The pathogenesis of H.pylori is contributed by its virulence factors including urease,flagella,vacuolating cytotoxin A(VacA),cytotoxin-associated gene antigen(Cag A),and others.Of those virulence factors,VacA and CagA play the key roles.Infection with H.pylori vacA-positive strains can lead to vacuolation and apoptosis,whereas infection with cagA-positive strains might result in severe gastric inflammation and gastric cancer.Numerous medicinal plants have been reported for their anti-H.pylori activity,and the relevant active compounds including polyphenols,flavonoids,quinones,coumarins,terpenoids,and alkaloids have been studied.The anti-H.pylori action mechanisms,including inhibition of enzymatic(urease,DNA gyrase,dihydrofolate reductase,N-acetyltransferase,and myeloperoxidase)and adhesive activities,high redox potential,and hydrophilic/hydrophobic natures of compounds,have also been discussed in detail.H.pylori-induced gastric inflammation may progress to superficial gastritis,atrophic gastritis,and finally gastric cancer.Many natural products have anti-H.pylori-induced inflammation activity and the relevant mechanisms include suppression of nuclear factor-κB and mitogen-activated protein kinase pathway activation and inhibition of oxidative stress.Anti-H.pylori induced gastric inflammatory effects of plant products,including quercetin,apigenin,carotenoids-rich algae,tea product,garlic extract,apple peel polyphenol,and finger-root extract,have been documented.In conclusion,many medicinal plant products possess anti-H.pylori activity as well as an anti-H.pylori-induced gastric inflammatory effect.Those plant products have showed great potential as pharmaceutical candidates for H.pylori eradication and H.pylori induced related gastric disease prevention.展开更多
Objective: To construct plant transformation vector containing Escherichia coli heat-labile enterotoxin B subunit(LT-B) gene and generate LT-B transgenic tobacco plants. Methods: The LT-B coding sequence was amplified...Objective: To construct plant transformation vector containing Escherichia coli heat-labile enterotoxin B subunit(LT-B) gene and generate LT-B transgenic tobacco plants. Methods: The LT-B coding sequence was amplified from pMMB68 by PCR, subcloned into middle vector pUCmT and binary vector pBI121 to obtain plant expression vector pBI-LTB, in which LT-B expression was controlled under the Cauliflower mosaic virus (CaMV) 35S promoter. The tobacco plants (Nicotiana tobacum L.Cuttivar Xanthi) were transformed by co-cultivating leaf discs method via Agrobacterium tumefaciens LBA4404 harboring the plant expression vector. The regenerated transgenic tobacco plants were selected by kanamycin and confirmed by PCR, Southern blot, Western blot and ELISA. Results:LT-B gene integrated in the tobacco genomic DNA and were expressed in 9 strains of transgenic tobacco plants. The yield was varied from 3.36-10.56 ng/mg total soluble tobacco leaf protein. Conclusion: The plant binary expression vector pBI-LTB was constructed successfully, and transgenic LT-B tobacco plants was generated, and confirmed by Southern blot. The protein LT-B expressed by engineered plants was identified by Western blot analysis and had the expected molecular weight of LT-B pentamer protein. This result is an important step close to developing an edible vaccine and supplying a mucasal immunoajuvant, which will contribute to the prevention of mucosa-route evading pathogen.展开更多
In plant cultivation, the number of photons is more important than the light energy from the chemical reactions that occur during photosynthesis. In addition, the blue and red photon flux (B/R) ratio is an important p...In plant cultivation, the number of photons is more important than the light energy from the chemical reactions that occur during photosynthesis. In addition, the blue and red photon flux (B/R) ratio is an important parameter for plant cultivation. Here we discuss the effect of the spectral irradiance distribution and the B/R ratio on plant cultivation. We cultivated lettuce seedlings, Lactuca sativa L. Cv. Okayama, using a light-emitting diode illumination system that can precisely control the spectral irradiance distribution and B/R ratio. The B/R ratio varied from 0.36 to 2.06 according to the intensity of the blue light when the photosynthetic photon flux density values were sufficient to ensure the 150 - 200?μmol⋅m−2⋅s−1.?High photon flux densities of blue light result in reduced plant length, plant height, and leaf area, thereby suggesting its role in the suppression of leaf growth. Therefore, we conclude that a lower photon flux of blue light (B/R Ratio) is optimal for lettuce cultivation.展开更多
Aiming to meet the demand of the country＇ s nuclear demonstration project on the CAP1400 nuclear power plant, Baosteel uses the roll-bonding technology and develops the SA-533 Type B CL. 1 ＋ SA-240 Type 304L high-st...Aiming to meet the demand of the country＇ s nuclear demonstration project on the CAP1400 nuclear power plant, Baosteel uses the roll-bonding technology and develops the SA-533 Type B CL. 1 ＋ SA-240 Type 304L high-strength and high-toughness clad steel plate with a shear strength of over 310 MPa for the nuclear power plant＇ s safety injection tank. The properties of the quenched and tempered and the simulated post-weld heat treatment states are systematically studied herein through a comprehensive inspection and evaluation of the composition,microstructure,and properties of the clad steel plate. The results show that the bonding interface has high shear strength and that the base metal has high strength and good toughness at low temperatures. Hence, the performance fully meets the technical requirements of the CAP1400 nuclear power plant＇ s safety injection tank in the country＇ s nuclear demonstration project. The roll-bonded clad steel plate can be used to manufacture the safety injection tank of the CAP1400 nuclear power plant.展开更多
基金the Natinnal Biotechnology Reseaxch Project of 863 High Technology, contract No. 101-01-01-02.
文摘After pre-culture and treatment of osmosis, cotyledons of immature peanut (Arachis hypogaea L.) zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene. Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin. Under continuous selection, hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons. The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR (polymerase chain reaction) for the intron-gus gene and by Southern hybridization of the hph gene. GUS enzyme activity was detected in leaflets from transgenic plants but not from control, non-transformed plants. The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.
基金supported by the National Key Research and Development Program of China (2016YFD0100605)the National Natural Science Foundation of China (31271720)
文摘Stress associated proteins（SAPs） are the A20/AN1 zinc-finger proteins which confer to abiotic stresses in plants. In this study, TaSAP7-B, including two AN1 domains, was isolated from B genome of wheat（Triticum aestivum L.）. Sequencing analysis on TaSAP7-B illustrated one In Del（insertion-deletion） and one SNP（single nucleotide polymorphism） in the promoter region while no diversity was observed in the coding region. On the basis of SNP in the promoter region（–260 bp）, a dCAPS（derived cleaved amplified polymorphic sequences） marker SNP-260 was developed for TaSAP7-B. Using a natural population consisting of 262 wheat accessions, significant associations were detected between the marker SNP-260 and agronomic traits, such as plant height（PH）, peduncle length（PL）, length of penultimate internode（LPI）, number of spike per plant（NSP）, and 1 000-grain weight（TGW）. Two genotypes were identified using marker SNP-260 in the natural population. Among them, the genotypes possessing C allele exhibited a higher TGW and shorter PH than the T genotypes. Hence, base C was considered as the superior allele. The dCAPS marker of TaSAP7-B can be instrumental for marker-assisted selection for high grain size and short plant height.
文摘More than 50%of the world population is infected with Helicobacter pylori(H.pylori).The bacterium highly links to peptic ulcer diseases and duodenal ulcer,which was classified as a groupⅠcarcinogen in 1994 by the WHO.The pathogenesis of H.pylori is contributed by its virulence factors including urease,flagella,vacuolating cytotoxin A(VacA),cytotoxin-associated gene antigen(Cag A),and others.Of those virulence factors,VacA and CagA play the key roles.Infection with H.pylori vacA-positive strains can lead to vacuolation and apoptosis,whereas infection with cagA-positive strains might result in severe gastric inflammation and gastric cancer.Numerous medicinal plants have been reported for their anti-H.pylori activity,and the relevant active compounds including polyphenols,flavonoids,quinones,coumarins,terpenoids,and alkaloids have been studied.The anti-H.pylori action mechanisms,including inhibition of enzymatic(urease,DNA gyrase,dihydrofolate reductase,N-acetyltransferase,and myeloperoxidase)and adhesive activities,high redox potential,and hydrophilic/hydrophobic natures of compounds,have also been discussed in detail.H.pylori-induced gastric inflammation may progress to superficial gastritis,atrophic gastritis,and finally gastric cancer.Many natural products have anti-H.pylori-induced inflammation activity and the relevant mechanisms include suppression of nuclear factor-κB and mitogen-activated protein kinase pathway activation and inhibition of oxidative stress.Anti-H.pylori induced gastric inflammatory effects of plant products,including quercetin,apigenin,carotenoids-rich algae,tea product,garlic extract,apple peel polyphenol,and finger-root extract,have been documented.In conclusion,many medicinal plant products possess anti-H.pylori activity as well as an anti-H.pylori-induced gastric inflammatory effect.Those plant products have showed great potential as pharmaceutical candidates for H.pylori eradication and H.pylori induced related gastric disease prevention.
基金Supported by the National Natural Science Foundation ofChina (No. 30070848)
文摘Objective: To construct plant transformation vector containing Escherichia coli heat-labile enterotoxin B subunit(LT-B) gene and generate LT-B transgenic tobacco plants. Methods: The LT-B coding sequence was amplified from pMMB68 by PCR, subcloned into middle vector pUCmT and binary vector pBI121 to obtain plant expression vector pBI-LTB, in which LT-B expression was controlled under the Cauliflower mosaic virus (CaMV) 35S promoter. The tobacco plants (Nicotiana tobacum L.Cuttivar Xanthi) were transformed by co-cultivating leaf discs method via Agrobacterium tumefaciens LBA4404 harboring the plant expression vector. The regenerated transgenic tobacco plants were selected by kanamycin and confirmed by PCR, Southern blot, Western blot and ELISA. Results:LT-B gene integrated in the tobacco genomic DNA and were expressed in 9 strains of transgenic tobacco plants. The yield was varied from 3.36-10.56 ng/mg total soluble tobacco leaf protein. Conclusion: The plant binary expression vector pBI-LTB was constructed successfully, and transgenic LT-B tobacco plants was generated, and confirmed by Southern blot. The protein LT-B expressed by engineered plants was identified by Western blot analysis and had the expected molecular weight of LT-B pentamer protein. This result is an important step close to developing an edible vaccine and supplying a mucasal immunoajuvant, which will contribute to the prevention of mucosa-route evading pathogen.
文摘In plant cultivation, the number of photons is more important than the light energy from the chemical reactions that occur during photosynthesis. In addition, the blue and red photon flux (B/R) ratio is an important parameter for plant cultivation. Here we discuss the effect of the spectral irradiance distribution and the B/R ratio on plant cultivation. We cultivated lettuce seedlings, Lactuca sativa L. Cv. Okayama, using a light-emitting diode illumination system that can precisely control the spectral irradiance distribution and B/R ratio. The B/R ratio varied from 0.36 to 2.06 according to the intensity of the blue light when the photosynthetic photon flux density values were sufficient to ensure the 150 - 200?μmol⋅m−2⋅s−1.?High photon flux densities of blue light result in reduced plant length, plant height, and leaf area, thereby suggesting its role in the suppression of leaf growth. Therefore, we conclude that a lower photon flux of blue light (B/R Ratio) is optimal for lettuce cultivation.
文摘Aiming to meet the demand of the country＇ s nuclear demonstration project on the CAP1400 nuclear power plant, Baosteel uses the roll-bonding technology and develops the SA-533 Type B CL. 1 ＋ SA-240 Type 304L high-strength and high-toughness clad steel plate with a shear strength of over 310 MPa for the nuclear power plant＇ s safety injection tank. The properties of the quenched and tempered and the simulated post-weld heat treatment states are systematically studied herein through a comprehensive inspection and evaluation of the composition,microstructure,and properties of the clad steel plate. The results show that the bonding interface has high shear strength and that the base metal has high strength and good toughness at low temperatures. Hence, the performance fully meets the technical requirements of the CAP1400 nuclear power plant＇ s safety injection tank in the country＇ s nuclear demonstration project. The roll-bonded clad steel plate can be used to manufacture the safety injection tank of the CAP1400 nuclear power plant.
