The promoter region of cauliflower mosaic virus (CaMV) 35s RNA was employed to construct an intermediate expression vector which can be used in Ti plasmid system of Agro-bacterium tumefaciens. The original plasmid, wh...The promoter region of cauliflower mosaic virus (CaMV) 35s RNA was employed to construct an intermediate expression vector which can be used in Ti plasmid system of Agro-bacterium tumefaciens. The original plasmid, which contains a polylinker between CaMV 35s RNA and its 3' termination signal in pUC18 was modified to have another antibiotic resistance marker (kanamycin resistance gene Kmr) to facilitate the selection of recombinant with Ti plasmid. Octopine synthase (ocs) structural gene was inserted into this vector downstream of CaMV 35s RNA promoter. This chimaeric gene was introduced into integrative Ti plasmid vector pGV3850, and then transformed into Nicotiana tobaccum cells. A binary plasmid vector was also used to introduce the chimaeric gene into tobacco cells. In both cases, the expression of ocs gene was demonstrated. The amount of oc-topine was much more than the nopaline synthesized by no-paline synthase (nos) gene transferred at the same time with Ti plasmid vector. This demonstrated that CaMV 35s RNA promoter is stronger in transcriptional function than the promoter of nos in tobacco cells.展开更多
我们通过体外多聚腺苷酸化的大鼠正常肝7 s RNA,克隆了它的cDNA片段。其中一个克隆p 24的7 s cDNA插入顺序为180个碱基对,其顺序与大鼠Novikoff肝癌7 s RNA顺序比较,存在一个碱基的置换。用这个克隆提供的探针我们比较了大鼠肝细胞和肝...我们通过体外多聚腺苷酸化的大鼠正常肝7 s RNA,克隆了它的cDNA片段。其中一个克隆p 24的7 s cDNA插入顺序为180个碱基对,其顺序与大鼠Novikoff肝癌7 s RNA顺序比较,存在一个碱基的置换。用这个克隆提供的探针我们比较了大鼠肝细胞和肝癌细胞7 s RNA的基因拷贝数,基因组结构和在细胞内分布。结果表明:7 s RNA基因是多拷贝基因家族;7 s RNA在细胞癌变后含量下降;大约40%7 s RNA分布在细胞核内。我们还就7 s RNA具有调控基因表达功能的可能性进行了讨论。展开更多
A study was conducted on the identifications of the degraded samples of sika deer (Cervus nippon) and red deer (Cervus elaphus) by phylogenetic and nucleotide distance analysis of partial Cytb and 12s rRNA genes s...A study was conducted on the identifications of the degraded samples of sika deer (Cervus nippon) and red deer (Cervus elaphus) by phylogenetic and nucleotide distance analysis of partial Cytb and 12s rRNA genes sequences. 402 bp Cytb genes were achieved by PCR-sequencing using DNA extracted from 8 case samples, and contrasted with 27 sequences of Cytb gene downloaded from GenBank database. The values of three nucleotide distance between three suspected samples and sika deer were identical (0.026±0.006), which was smaller than the smallest nucleotide distance between eastern red deer and sika deer (0.036). Furthermore, phylogenetic analysis of sika deer and red deer indicated that the evidences located within the same cluster as sika deer. The evidences were sika deer materials. As the same way, other three suspected samples were derived from red deer. The results were further confirmed by phylogenetic and nucleotide distance analysis of 387 bp 12s rRNA gene. The method was powerful and less time-consuming and helpful to reduce the related cases with wildlife.展开更多
To study the phylogeny of Hynobiidae, we amplified DNA fragments of 470 bp 16S ribosomal RNA (16S rRNA) gene on mitochondrial DNA from Ranodon sibiricus and Ranodon tsinpaensis. PCR products were cloned into PMD18 T v...To study the phylogeny of Hynobiidae, we amplified DNA fragments of 470 bp 16S ribosomal RNA (16S rRNA) gene on mitochondrial DNA from Ranodon sibiricus and Ranodon tsinpaensis. PCR products were cloned into PMD18 T vector after purification. These sequences were determined and deposited in the GenBank (accession numbers: AY373459 for Ranodon sibiricus, AY372534 for Ranodon tsinpaensis). By comparing the nucleotide differences of 16S ribosomal RNA sequences among Liua shihi,Pseudohynobius flavomaculatus and Batrachuperus genus from GenBank database,we analyzed the divergences and base substitution among these sequences with the MEGA software. The molecular results support that B tibetanus, B pinchonii and B karlschmidti are classified into three valid species. Liua shihi has closer phylogenetic relationships to Ranodon tsinpaensis than to other species. More our results reveal that Pseudohynobius flavomaculatus is not a synonym of Ranodon tsinpaensis. .展开更多
To design and synthesize neamine analogues modified at 5 position offing Ⅱ, which could improve the binding affinity of aminoglycosides to 16S RNA. Started from neomycin B, modified neamine analogues were synthesized...To design and synthesize neamine analogues modified at 5 position offing Ⅱ, which could improve the binding affinity of aminoglycosides to 16S RNA. Started from neomycin B, modified neamine analogues were synthesized through organic reactions such as hydrolysis, protection, nucleophilic substitution, deprotection and reduction. The interaction of the target compounds with A-site RNA in E. coli. ribosome (16S RNA) was determined by surface plasmon resonance (SPR), respectively. Six target compounds were synthesized. Some of them showed antibacterial activities and enhanced affinity to 16S RNA at 10^-3M in vitro. Introduction amino or aliphatic amino group at 5 position offing Ⅱ in neamine would maintained antibacterial activities as well as increase binding affinity to 16S RNA. Furthermore, there is almost no influence on the stability of drug/16S RNA complex by inverting the configuration of 5-hydroxyl group at ring Ⅱ.展开更多
河南某鸡场约4周龄鸡疑似发生鸡组织滴虫病。根据鸡组织滴虫18 S rRNA序列设计引物,提取肝脏、盲肠内容物寄生虫DNA,采用PCR方法检测。结果表明,PCR扩增到与预期大小一致的产物,经测序比对,证实为鸡组织滴虫感染。所建立的PCR方法具有...河南某鸡场约4周龄鸡疑似发生鸡组织滴虫病。根据鸡组织滴虫18 S rRNA序列设计引物,提取肝脏、盲肠内容物寄生虫DNA,采用PCR方法检测。结果表明,PCR扩增到与预期大小一致的产物,经测序比对,证实为鸡组织滴虫感染。所建立的PCR方法具有灵敏、特异、快速等优点,不仅能用于鸡组织滴虫病临床诊断,还能用于开展流行病学研究。展开更多
文摘The promoter region of cauliflower mosaic virus (CaMV) 35s RNA was employed to construct an intermediate expression vector which can be used in Ti plasmid system of Agro-bacterium tumefaciens. The original plasmid, which contains a polylinker between CaMV 35s RNA and its 3' termination signal in pUC18 was modified to have another antibiotic resistance marker (kanamycin resistance gene Kmr) to facilitate the selection of recombinant with Ti plasmid. Octopine synthase (ocs) structural gene was inserted into this vector downstream of CaMV 35s RNA promoter. This chimaeric gene was introduced into integrative Ti plasmid vector pGV3850, and then transformed into Nicotiana tobaccum cells. A binary plasmid vector was also used to introduce the chimaeric gene into tobacco cells. In both cases, the expression of ocs gene was demonstrated. The amount of oc-topine was much more than the nopaline synthesized by no-paline synthase (nos) gene transferred at the same time with Ti plasmid vector. This demonstrated that CaMV 35s RNA promoter is stronger in transcriptional function than the promoter of nos in tobacco cells.
文摘我们通过体外多聚腺苷酸化的大鼠正常肝7 s RNA,克隆了它的cDNA片段。其中一个克隆p 24的7 s cDNA插入顺序为180个碱基对,其顺序与大鼠Novikoff肝癌7 s RNA顺序比较,存在一个碱基的置换。用这个克隆提供的探针我们比较了大鼠肝细胞和肝癌细胞7 s RNA的基因拷贝数,基因组结构和在细胞内分布。结果表明:7 s RNA基因是多拷贝基因家族;7 s RNA在细胞癌变后含量下降;大约40%7 s RNA分布在细胞核内。我们还就7 s RNA具有调控基因表达功能的可能性进行了讨论。
文摘A study was conducted on the identifications of the degraded samples of sika deer (Cervus nippon) and red deer (Cervus elaphus) by phylogenetic and nucleotide distance analysis of partial Cytb and 12s rRNA genes sequences. 402 bp Cytb genes were achieved by PCR-sequencing using DNA extracted from 8 case samples, and contrasted with 27 sequences of Cytb gene downloaded from GenBank database. The values of three nucleotide distance between three suspected samples and sika deer were identical (0.026±0.006), which was smaller than the smallest nucleotide distance between eastern red deer and sika deer (0.036). Furthermore, phylogenetic analysis of sika deer and red deer indicated that the evidences located within the same cluster as sika deer. The evidences were sika deer materials. As the same way, other three suspected samples were derived from red deer. The results were further confirmed by phylogenetic and nucleotide distance analysis of 387 bp 12s rRNA gene. The method was powerful and less time-consuming and helpful to reduce the related cases with wildlife.
文摘To study the phylogeny of Hynobiidae, we amplified DNA fragments of 470 bp 16S ribosomal RNA (16S rRNA) gene on mitochondrial DNA from Ranodon sibiricus and Ranodon tsinpaensis. PCR products were cloned into PMD18 T vector after purification. These sequences were determined and deposited in the GenBank (accession numbers: AY373459 for Ranodon sibiricus, AY372534 for Ranodon tsinpaensis). By comparing the nucleotide differences of 16S ribosomal RNA sequences among Liua shihi,Pseudohynobius flavomaculatus and Batrachuperus genus from GenBank database,we analyzed the divergences and base substitution among these sequences with the MEGA software. The molecular results support that B tibetanus, B pinchonii and B karlschmidti are classified into three valid species. Liua shihi has closer phylogenetic relationships to Ranodon tsinpaensis than to other species. More our results reveal that Pseudohynobius flavomaculatus is not a synonym of Ranodon tsinpaensis. .
基金National Natural Science Foundation of China(Grant No.20332010)the Ministry of Science and Technology of China(Grant No.2005BA711A04).
文摘To design and synthesize neamine analogues modified at 5 position offing Ⅱ, which could improve the binding affinity of aminoglycosides to 16S RNA. Started from neomycin B, modified neamine analogues were synthesized through organic reactions such as hydrolysis, protection, nucleophilic substitution, deprotection and reduction. The interaction of the target compounds with A-site RNA in E. coli. ribosome (16S RNA) was determined by surface plasmon resonance (SPR), respectively. Six target compounds were synthesized. Some of them showed antibacterial activities and enhanced affinity to 16S RNA at 10^-3M in vitro. Introduction amino or aliphatic amino group at 5 position offing Ⅱ in neamine would maintained antibacterial activities as well as increase binding affinity to 16S RNA. Furthermore, there is almost no influence on the stability of drug/16S RNA complex by inverting the configuration of 5-hydroxyl group at ring Ⅱ.
文摘河南某鸡场约4周龄鸡疑似发生鸡组织滴虫病。根据鸡组织滴虫18 S rRNA序列设计引物,提取肝脏、盲肠内容物寄生虫DNA,采用PCR方法检测。结果表明,PCR扩增到与预期大小一致的产物,经测序比对,证实为鸡组织滴虫感染。所建立的PCR方法具有灵敏、特异、快速等优点,不仅能用于鸡组织滴虫病临床诊断,还能用于开展流行病学研究。