Artemisia annua L. produces small amounts of the sesquiterpenoid artemisinin, which is used for treatment of malaria. A worldwide shortage of the drug has led to intense research to increase the yield of artemisinin i...Artemisia annua L. produces small amounts of the sesquiterpenoid artemisinin, which is used for treatment of malaria. A worldwide shortage of the drug has led to intense research to increase the yield of artemisinin in the plant. In order to study the regulation of expression of a key enzyme of artemisinin biosynthesis, the promoter region of the key enzyme amorpha-4,11-diene synthase (ADS) was cloned and fused with the β-glucuronidase (GUS) reporter gene. Transgenic plants of A. annua expressing this fusion were generated and studied. Transgenic plants expressing the GUS gene were used to establish the activity of the cloned promoter by a GUS activity staining procedure. GUS under the control of the ADS promoter showed specific expression in glandular trichomes. The activity of the ADS promoter varies temporally and in old tissues essentially no GUS staining could be observed. The expression pattern of GUS and ADS in aerial parts of the transgenic plant was essentially the same indicating that the cis-elements controlling glandular trichome specific expression are included in the cloned promoter. However, some cis-element(s) that control expression in root and old leaf appears to be missing in the cloned promoter. Furthermore, qPCR was used to compare the activity of the wild-type ADS promoter with that of the cloned ADS promoter. The latter promoter showed a considerably lower activity than the wild-type promoter as judged from the levels of GUS and ADS transcripts, respectively, which may be due to the removal of an enhancing cis-element from the ADS promoter. The ADS gene is specifically expressed in stalk and secretory cells of glandular trichomes of A. annua.展开更多
目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC–MS/MS)同时测定鸡肉中克伦特罗、溴布特罗、溴代克伦特罗、特布他林、沙丁胺醇5种β-受体激动剂残留量的分析方法。方法...目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC–MS/MS)同时测定鸡肉中克伦特罗、溴布特罗、溴代克伦特罗、特布他林、沙丁胺醇5种β-受体激动剂残留量的分析方法。方法在鸡肉样品加入β-葡萄糖醛酸酶进行水解,经混合阳离子(MCX)固相萃取柱净化,利用超高效液相色谱-串联质谱法检测,内标法定量。同时考察了不同的酶制剂对鸡肉中β-受体激动剂含量测定的影响。结果 5种β-受体激动剂在0.1～50μg/kg浓度范围内呈现良好的线性关系,相关系数均大于0.9991,方法的检出限(limits of detection,LOD)为0.02～0.24μg/kg,定量限(limits of quantitation,LOQ)为0.1～0.71μg/kg。在0.5、5、40μg/kg添加水平下,5种β-受体激动剂的平均回收率为77.8%～117.5%,相对标准偏差小于7.9%。在相同的条件下IMCSzyme~?比蜗牛β-葡萄糖醛酸酶能够更有效地解离鸡肉中轭合的特布他林和沙丁胺醇,测得的含量提高,结果稳定。结论本方法缩短了样品水解时间,提高了β-受体激动剂的检测效率,适用于同时检测鸡肉中5种β-受体激动剂含量。展开更多
Two plasmids, p13GUS and p13GUS2, were constructed to create a gene trap system containing the promotsriess β-glucuronidase （GUS） reporter gene in the T-DNA region. Transformation of these two plasmids into the ric...Two plasmids, p13GUS and p13GUS2, were constructed to create a gene trap system containing the promotsriess β-glucuronidase （GUS） reporter gene in the T-DNA region. Transformation of these two plasmids into the rice variety Zhonghua 11 （Oryza sativa ssp. japonica cv.）, mediated by Agrobacterium tumefaciens, resulted in 942 independent transgenic lines. Histochemical GUS assays revealed that 31 To plants had various patterns of the reporter gene expression, including expression in only one tissue, and simultaneously in two or more tissues. Hygromycin-resistsnt （hygr） homozygotes were screened and the copy number of the T-DNA inserts was determined in the GUS-positive transgenic plants. The flanking sequences of the T-DNA were isolated by inverse-polymerase chain reaction and the insert positions on the rice genome of T-DNA were determined by a basic local alignment search tool in the GUS-positive transgenic plants transformed with plasmid p13GUS. Moreover, calli induced from the seeds of the T1 generation of 911 GUS-negative transgenic lines were subjected to stress and hormone treatments. Histochemical GUS assays were carried out on the calli before and after treatment. The results revealed that calli from 21 lines displayed differential GUS expression after treatment. All of these data demonstrated that this trap system is suitable for identifying rice genes, including those that are sensitive to induction.展开更多
文摘Artemisia annua L. produces small amounts of the sesquiterpenoid artemisinin, which is used for treatment of malaria. A worldwide shortage of the drug has led to intense research to increase the yield of artemisinin in the plant. In order to study the regulation of expression of a key enzyme of artemisinin biosynthesis, the promoter region of the key enzyme amorpha-4,11-diene synthase (ADS) was cloned and fused with the β-glucuronidase (GUS) reporter gene. Transgenic plants of A. annua expressing this fusion were generated and studied. Transgenic plants expressing the GUS gene were used to establish the activity of the cloned promoter by a GUS activity staining procedure. GUS under the control of the ADS promoter showed specific expression in glandular trichomes. The activity of the ADS promoter varies temporally and in old tissues essentially no GUS staining could be observed. The expression pattern of GUS and ADS in aerial parts of the transgenic plant was essentially the same indicating that the cis-elements controlling glandular trichome specific expression are included in the cloned promoter. However, some cis-element(s) that control expression in root and old leaf appears to be missing in the cloned promoter. Furthermore, qPCR was used to compare the activity of the wild-type ADS promoter with that of the cloned ADS promoter. The latter promoter showed a considerably lower activity than the wild-type promoter as judged from the levels of GUS and ADS transcripts, respectively, which may be due to the removal of an enhancing cis-element from the ADS promoter. The ADS gene is specifically expressed in stalk and secretory cells of glandular trichomes of A. annua.
文摘目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC–MS/MS)同时测定鸡肉中克伦特罗、溴布特罗、溴代克伦特罗、特布他林、沙丁胺醇5种β-受体激动剂残留量的分析方法。方法在鸡肉样品加入β-葡萄糖醛酸酶进行水解,经混合阳离子(MCX)固相萃取柱净化,利用超高效液相色谱-串联质谱法检测,内标法定量。同时考察了不同的酶制剂对鸡肉中β-受体激动剂含量测定的影响。结果 5种β-受体激动剂在0.1～50μg/kg浓度范围内呈现良好的线性关系,相关系数均大于0.9991,方法的检出限(limits of detection,LOD)为0.02～0.24μg/kg,定量限(limits of quantitation,LOQ)为0.1～0.71μg/kg。在0.5、5、40μg/kg添加水平下,5种β-受体激动剂的平均回收率为77.8%～117.5%,相对标准偏差小于7.9%。在相同的条件下IMCSzyme~?比蜗牛β-葡萄糖醛酸酶能够更有效地解离鸡肉中轭合的特布他林和沙丁胺醇,测得的含量提高,结果稳定。结论本方法缩短了样品水解时间,提高了β-受体激动剂的检测效率,适用于同时检测鸡肉中5种β-受体激动剂含量。
基金grants from the Ministry of Science and Technology of China(2002AA2Z1003 and 2005CB120803).
文摘Two plasmids, p13GUS and p13GUS2, were constructed to create a gene trap system containing the promotsriess β-glucuronidase （GUS） reporter gene in the T-DNA region. Transformation of these two plasmids into the rice variety Zhonghua 11 （Oryza sativa ssp. japonica cv.）, mediated by Agrobacterium tumefaciens, resulted in 942 independent transgenic lines. Histochemical GUS assays revealed that 31 To plants had various patterns of the reporter gene expression, including expression in only one tissue, and simultaneously in two or more tissues. Hygromycin-resistsnt （hygr） homozygotes were screened and the copy number of the T-DNA inserts was determined in the GUS-positive transgenic plants. The flanking sequences of the T-DNA were isolated by inverse-polymerase chain reaction and the insert positions on the rice genome of T-DNA were determined by a basic local alignment search tool in the GUS-positive transgenic plants transformed with plasmid p13GUS. Moreover, calli induced from the seeds of the T1 generation of 911 GUS-negative transgenic lines were subjected to stress and hormone treatments. Histochemical GUS assays were carried out on the calli before and after treatment. The results revealed that calli from 21 lines displayed differential GUS expression after treatment. All of these data demonstrated that this trap system is suitable for identifying rice genes, including those that are sensitive to induction.
