Expression of rol genes from Ri plasmid of Agrobacterium rhizogenes not only leads to the excessive formation of adventitious roots, but also exhibits various genetically modified characteristics that have bro...Expression of rol genes from Ri plasmid of Agrobacterium rhizogenes not only leads to the excessive formation of adventitious roots, but also exhibits various genetically modified characteristics that have broad prospects for the application of plant genetic improvement. Since the 1980s of the last century, much progress has been made in the studies of A. rhizogenes, in particular the agropine type Ri plasmid rol genes and their applications for plant genetic improvement, which involves the structure and function of Ri plasmid, the characters of rol genes, the influence of rol genes expression on plants growth and development, and the applications of rol genes for genetic improvement of forest tree. In this paper, the advances in this field are reviewed and the existing problems about the application of rol genes for genetic improvement of forest tree are also discussed.展开更多
The rol genes cloned from Agrobacterium rhizogenes were transferred to the cotton genomevia Agrobacterium-mediated transformation. Molecular analyses and developmentalidentification of the putative transgenic plants w...The rol genes cloned from Agrobacterium rhizogenes were transferred to the cotton genomevia Agrobacterium-mediated transformation. Molecular analyses and developmentalidentification of the putative transgenic plants were carried out by means of PCR,Southern blotting and field characterization. The results showed that the expression ofrol genes greatly increased the rooting ability of the transgenic plants, and changed theplant development. Highly male-sterile plants with strong apical dominance and fertileplants with short internodes, stunted growth and improved economic characteristics weresegregated from the T1 transgenic lines of wild rol B gene and the rol B gene driven by35S promoter. The transgenic lines of rol ABC construct usually had normal boll settingand slow growth. Therefore we concluded that the rol genes, modified in suitable ways,could be used to create new cotton varieties with some highly valuable characteristics.展开更多
Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhi...Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae,and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor,recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed.Compared with the wild-type ROL-displaying yeast,the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate.To our knowledge,this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction.Consequently,the yeast whole-cell ROL biocatalyst was constructed with high activity.The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °C.Furthermore,this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.展开更多
Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of trans-genie plants was induced successfully fr...Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of trans-genie plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.展开更多
Objective: Artemisia annua is the chief source of artemisinin, a potent antimalarial agent, in which other bioactive phytochemicals are also present. Due to low levels of bioactive compounds including artemisinin and ...Objective: Artemisia annua is the chief source of artemisinin, a potent antimalarial agent, in which other bioactive phytochemicals are also present. Due to low levels of bioactive compounds including artemisinin and flavonoids, it is necessary to increase the level of the secondary metabolites by regulating the expression of rol genes in the plant.Methods: A hybrid variety of A. annua(Hyb1209 r, Shennong) developed by the Centre for Novel Agricultural Products, University of York, UK, was selected to produce transgenics of rolB and rolC genes. Genetic transformation was carried out via Agrobacterium tumefaciens GV3101 harboring rolB and rolC genes of Agrobacterium rhizogenes cloned separately. HPLC was used for the qualitative and quantitative analysis of flavonoids and artemisinin. Furthermore, thin layer chromatography(TLC) was also used to analyze artemisinin content.Results: Comparative analysis via HPLC revealed considerable enhancement in the phytochemical content of transgenic A. annua plants as compared to the wild type plant. Transgenics of rolB gene showed an average increase of 321% in rutin, 97.2% in caffeic acid, and 218.4% in myricetin, respectively. In the case of rolC gene transgenics, an average increase of 197.5% in rutin, 76.3% in caffeic acid, and 209.3%in myricetin was observed. Transgenics of rolB and rolC genes showed a 14.3%–28.6% and 2.8%–12.7% increase in artemisinin content respectively by HPLC analysis. TLC analysis showed that an average 142.2%and 110.2% enhancement in artemisinin for rolB and rolC transgenics respectively, compared with the wild type. An enhanced production of total flavonoids(average 30.2% and 25.5% increase in rolB and rolC transgenics, respectively) and total phenolics(average 34.3% and 25.8% increase in rolB and rolC transgenics, respectively) was observed as a result of transformation. Transformed A. annua plants showed improved free radical scavenging activity(average 46.5% and 29.1% increase in rolB and rolC transgenics,respectively) and total reducing po展开更多
Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a sourc...Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on cuttings was determined using methods of X-ray scattering and differential scanning microcalorimetry (DSC). It was found that in starch from tubers of rolB plants the melting temperature of crystalline lamella was lower and their thickness was less than that in wild-type potato. In tubers of rolC plants starch differed from starch in wild-type plants by a higher melting temperature, reduced melting enthalpy, and a greater thickness of crystalline lamellae. The melting of starch from tubers of rolC plants proceeded as the melting of two independent crystalline structures with melting temperatures of 338.0°K and 342.8°K. Overall data show that starches of different structure can be obtained by using transgenic approach.展开更多
This paper summarizes previous research on the contacts between the sixth Panchen Lama of Tibet and the British East India Company （EIC）. Extensive research has been done on the archives and travelogues written in E...This paper summarizes previous research on the contacts between the sixth Panchen Lama of Tibet and the British East India Company （EIC）. Extensive research has been done on the archives and travelogues written in English, yet further attention needs to be paid to the significance of these contacts to the Panchen Lama＇s historic visit to the Qing court around the same time. Although little is available in Chinese and Tibetan sources on this event, important questions have yet to be raised and discussed. Drawing upon what has been done on this topic, the author makes further use of Tibetan materials and the catalog of Manchu archives in the First Historical Archive of China, and concludes that the plan and efforts for the EIC to open its trade route to China through Tibet were essentially based on wishful thinking or false hope without thorough understanding of Tibet or Qing court, or the delicate relations between the two. Even though the EIC＇s late 18th century efforts through the Hindu merchant monk Gosain Purangir were in vain, examining the many contacts between the sixth Panchen Lama and the EIC and Purangir＇s trip to Beijing provide a novel perspective on the relations between Tibet and the Qing court in the second half of the 18th century. This inquiry also demonstrates that during the same period, Tibet was not a land of isolation; on the contrary, it was an integral part of＂the pre-modern globalization＂ process.展开更多
藏文佛传rgya cher rol pa由27品构成,记载了佛祖释迦牟尼从“兜率天降生”到“初转法轮”为止的主要经历。梵文原典名为Lalitavistara;对应的汉文翻译为《方广大庄严经》(有异译本《普曜经》);蒙古文翻译为yekede cˇenggegsen sudur...藏文佛传rgya cher rol pa由27品构成,记载了佛祖释迦牟尼从“兜率天降生”到“初转法轮”为止的主要经历。梵文原典名为Lalitavistara;对应的汉文翻译为《方广大庄严经》(有异译本《普曜经》);蒙古文翻译为yekede cˇenggegsen sudur。本文简要说明了rgya cher rol pa及其梵文原典、汉文翻译、蒙古文翻译之后,整理了rgya cher rol pa全27品的梵、藏、汉对照目录,梳理了国内外rgya cher rol pa的研究成果,从校勘、翻译、梵藏对比研究、蒙藏对比研究四方面进行了概述,对佛典的藏文译名的理解提出了自己的一点看法。展开更多
The effects of different arsenic （As） treatments on spatial pattern of radial oxygen loss （ROL）, iron （Fe） plaque formation and As accumulation in rice were investigated using three rice genotypes, planted under...The effects of different arsenic （As） treatments on spatial pattern of radial oxygen loss （ROL）, iron （Fe） plaque formation and As accumulation in rice were investigated using three rice genotypes, planted under greenhouse conditions. Arsenic was applied to soil at 50 and 100 mg/kg, with untreated soil used as a control having an average As concentration of 8.5 mg/kg. It was demonstrated that the ratio of ROL in root tips to that at the root base slightly decreased with increasing As concentration, suggesting that the spatial ROL patterns in these groups may be shifted from the “tight” barrier towards the “partial” barrier form. Furthermore, increasing As concentration led to a increase in Fe plaque formation on root surfaces. In addition, root As concentrations of genotypes in 50 and 100 mg/kg As treatments were significantly higher than that of control treatment （P〈0.05）. Grain As concentration of genotype Nanyangzhan （with lower ROL） was significantly higher （P〈0.05） than that of genotype CNT87059-3 with higher ROL.展开更多
文摘Expression of rol genes from Ri plasmid of Agrobacterium rhizogenes not only leads to the excessive formation of adventitious roots, but also exhibits various genetically modified characteristics that have broad prospects for the application of plant genetic improvement. Since the 1980s of the last century, much progress has been made in the studies of A. rhizogenes, in particular the agropine type Ri plasmid rol genes and their applications for plant genetic improvement, which involves the structure and function of Ri plasmid, the characters of rol genes, the influence of rol genes expression on plants growth and development, and the applications of rol genes for genetic improvement of forest tree. In this paper, the advances in this field are reviewed and the existing problems about the application of rol genes for genetic improvement of forest tree are also discussed.
基金the National Natural science Fundationof china(39970386)
文摘The rol genes cloned from Agrobacterium rhizogenes were transferred to the cotton genomevia Agrobacterium-mediated transformation. Molecular analyses and developmentalidentification of the putative transgenic plants were carried out by means of PCR,Southern blotting and field characterization. The results showed that the expression ofrol genes greatly increased the rooting ability of the transgenic plants, and changed theplant development. Highly male-sterile plants with strong apical dominance and fertileplants with short internodes, stunted growth and improved economic characteristics weresegregated from the T1 transgenic lines of wild rol B gene and the rol B gene driven by35S promoter. The transgenic lines of rol ABC construct usually had normal boll settingand slow growth. Therefore we concluded that the rol genes, modified in suitable ways,could be used to create new cotton varieties with some highly valuable characteristics.
基金Project supported by the National High-Tech R & D Program (863) of China (No. 2006AA10Z308)the National Science Foundation of China (No. 20776130)+1 种基金the Zhejiang Provincial Natural Science Foundation of China (No. Y4090309)the Zhejiang Provincial Science and Technology Program of China (No. 2009C32009)
文摘Surface display is effectively utilized to construct a whole-cell biocatalyst.Codon optimization has been proven to be effective in maximizing production of heterologous proteins in yeast.Here,the cDNA sequence of Rhizopus oryzae lipase (ROL) was optimized and synthesized according to the codon bias of Saccharomyces cerevisiae,and based on the Saccharomyces cerevisiae cell surface display system with α-agglutinin as an anchor,recombinant yeast displaying fully codon-optimized ROL with high activity was successfully constructed.Compared with the wild-type ROL-displaying yeast,the activity of the codon-optimized ROL yeast whole-cell biocatalyst (25 U/g dried cells) was 12.8-fold higher in a hydrolysis reaction using p-nitrophenyl palmitate (pNPP) as the substrate.To our knowledge,this was the first attempt to combine the techniques of yeast surface display and codon optimization for whole-cell biocatalyst construction.Consequently,the yeast whole-cell ROL biocatalyst was constructed with high activity.The optimum pH and temperature for the yeast whole-cell ROL biocatalyst were pH 7.0 and 40 °C.Furthermore,this whole-cell biocatalyst was applied to the hydrolysis of tributyrin and the resulted conversion of butyric acid reached 96.91% after 144 h.
文摘Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of trans-genie plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.
文摘Objective: Artemisia annua is the chief source of artemisinin, a potent antimalarial agent, in which other bioactive phytochemicals are also present. Due to low levels of bioactive compounds including artemisinin and flavonoids, it is necessary to increase the level of the secondary metabolites by regulating the expression of rol genes in the plant.Methods: A hybrid variety of A. annua(Hyb1209 r, Shennong) developed by the Centre for Novel Agricultural Products, University of York, UK, was selected to produce transgenics of rolB and rolC genes. Genetic transformation was carried out via Agrobacterium tumefaciens GV3101 harboring rolB and rolC genes of Agrobacterium rhizogenes cloned separately. HPLC was used for the qualitative and quantitative analysis of flavonoids and artemisinin. Furthermore, thin layer chromatography(TLC) was also used to analyze artemisinin content.Results: Comparative analysis via HPLC revealed considerable enhancement in the phytochemical content of transgenic A. annua plants as compared to the wild type plant. Transgenics of rolB gene showed an average increase of 321% in rutin, 97.2% in caffeic acid, and 218.4% in myricetin, respectively. In the case of rolC gene transgenics, an average increase of 197.5% in rutin, 76.3% in caffeic acid, and 209.3%in myricetin was observed. Transgenics of rolB and rolC genes showed a 14.3%–28.6% and 2.8%–12.7% increase in artemisinin content respectively by HPLC analysis. TLC analysis showed that an average 142.2%and 110.2% enhancement in artemisinin for rolB and rolC transgenics respectively, compared with the wild type. An enhanced production of total flavonoids(average 30.2% and 25.5% increase in rolB and rolC transgenics, respectively) and total phenolics(average 34.3% and 25.8% increase in rolB and rolC transgenics, respectively) was observed as a result of transformation. Transformed A. annua plants showed improved free radical scavenging activity(average 46.5% and 29.1% increase in rolB and rolC transgenics,respectively) and total reducing po
文摘Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on cuttings was determined using methods of X-ray scattering and differential scanning microcalorimetry (DSC). It was found that in starch from tubers of rolB plants the melting temperature of crystalline lamella was lower and their thickness was less than that in wild-type potato. In tubers of rolC plants starch differed from starch in wild-type plants by a higher melting temperature, reduced melting enthalpy, and a greater thickness of crystalline lamellae. The melting of starch from tubers of rolC plants proceeded as the melting of two independent crystalline structures with melting temperatures of 338.0°K and 342.8°K. Overall data show that starches of different structure can be obtained by using transgenic approach.
文摘This paper summarizes previous research on the contacts between the sixth Panchen Lama of Tibet and the British East India Company （EIC）. Extensive research has been done on the archives and travelogues written in English, yet further attention needs to be paid to the significance of these contacts to the Panchen Lama＇s historic visit to the Qing court around the same time. Although little is available in Chinese and Tibetan sources on this event, important questions have yet to be raised and discussed. Drawing upon what has been done on this topic, the author makes further use of Tibetan materials and the catalog of Manchu archives in the First Historical Archive of China, and concludes that the plan and efforts for the EIC to open its trade route to China through Tibet were essentially based on wishful thinking or false hope without thorough understanding of Tibet or Qing court, or the delicate relations between the two. Even though the EIC＇s late 18th century efforts through the Hindu merchant monk Gosain Purangir were in vain, examining the many contacts between the sixth Panchen Lama and the EIC and Purangir＇s trip to Beijing provide a novel perspective on the relations between Tibet and the Qing court in the second half of the 18th century. This inquiry also demonstrates that during the same period, Tibet was not a land of isolation; on the contrary, it was an integral part of＂the pre-modern globalization＂ process.
文摘藏文佛传rgya cher rol pa由27品构成,记载了佛祖释迦牟尼从“兜率天降生”到“初转法轮”为止的主要经历。梵文原典名为Lalitavistara;对应的汉文翻译为《方广大庄严经》(有异译本《普曜经》);蒙古文翻译为yekede cˇenggegsen sudur。本文简要说明了rgya cher rol pa及其梵文原典、汉文翻译、蒙古文翻译之后,整理了rgya cher rol pa全27品的梵、藏、汉对照目录,梳理了国内外rgya cher rol pa的研究成果,从校勘、翻译、梵藏对比研究、蒙藏对比研究四方面进行了概述,对佛典的藏文译名的理解提出了自己的一点看法。
基金Projects(41201493,31300815)supported by the National Natural Science Foundation of China
文摘The effects of different arsenic （As） treatments on spatial pattern of radial oxygen loss （ROL）, iron （Fe） plaque formation and As accumulation in rice were investigated using three rice genotypes, planted under greenhouse conditions. Arsenic was applied to soil at 50 and 100 mg/kg, with untreated soil used as a control having an average As concentration of 8.5 mg/kg. It was demonstrated that the ratio of ROL in root tips to that at the root base slightly decreased with increasing As concentration, suggesting that the spatial ROL patterns in these groups may be shifted from the “tight” barrier towards the “partial” barrier form. Furthermore, increasing As concentration led to a increase in Fe plaque formation on root surfaces. In addition, root As concentrations of genotypes in 50 and 100 mg/kg As treatments were significantly higher than that of control treatment （P〈0.05）. Grain As concentration of genotype Nanyangzhan （with lower ROL） was significantly higher （P〈0.05） than that of genotype CNT87059-3 with higher ROL.
