The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 int...The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.展开更多
High affinity phosphate transporterplays an important role in plantadapting to low phosphorus. Isolationof genes coding this kind of proteinhas attracted worldwide scholars toaccomplish. We aimed to isolate thegene an...High affinity phosphate transporterplays an important role in plantadapting to low phosphorus. Isolationof genes coding this kind of proteinhas attracted worldwide scholars toaccomplish. We aimed to isolate thegene and transfer it to target plants展开更多
Cytoplasmic male sterility(CMS) is a maternally inherited trait that results in the failure to produce functional pollen.It was identified in many plants,and it is widely used to exploit heterosis.
Interspecific hybrids and constructed research models have provided infor-mation on intracellular interactions. We used two introgressed, chromosomally differentiated strains (H4 and H2) derived from F1 hybrids of cro...Interspecific hybrids and constructed research models have provided infor-mation on intracellular interactions. We used two introgressed, chromosomally differentiated strains (H4 and H2) derived from F1 hybrids of crosses between D. prosaltans females and D. saltans males. In H4, the D. prosaltans chromosomes were eliminated. In H2, a mixture was maintained, preserving the entire genome of D. prosaltans (except the Y chromosome) and parts of the D. saltans genome. The IIR arm and a segment of chromosome III were eliminated. A third strain, used for comparison, was a normal D. prosaltans strain (P). This study aimed primarily to analyze the effect on the reproductive char-acteristics productivity (number of progeny) and sex-ratio caused by Wolbachia infection in interaction with different chromosome constitutions. For this, infected and uninfected flies were used in intrastrain cross combinations. Firstly, we analyzed the productivity of intracrosses of uninfected parents, in each strain, in order to detect the effects of intracellular interactions, in flies carrying different chromosome constitutions and sharing a Wolbach-ia-free, D. prosaltans cytoplasm. Data indicated that the chromosome parts that were eliminated, in H2, carry the isolating genes that impair productivity in hybrids of the two species, and suggested the occurrence of a nuclear/nuclear interaction. The analysis of Wolbachia-infected flies showed that the three strains presented different responses, depending on the chromosome constitution. As to productivity, the infection was harmful in P strain, in H2 behaved as mutualistic, and, in H4, produced the effect cytoplasmic incompatibility. As to sex-ratio, intracrosses showed significant differences in P and H4 strains. These results, associated with the cytological characteristics of the strains, pointed to the fundamental importance of host chromosome constitution to define the interactive process host/Wolbachia, and showed the flexibility of the endo-symbiont manifested in different forms of self-preservation.展开更多
The shikimate pathway enzyme 5-enolpyruvylshikimate 3-phosphate synthase (EPSPs) is the target of nonselective herbicide glyphosate. A partial rice epsps cDNA was generated by RT-PCR with primers designed according to...The shikimate pathway enzyme 5-enolpyruvylshikimate 3-phosphate synthase (EPSPs) is the target of nonselective herbicide glyphosate. A partial rice epsps cDNA was generated by RT-PCR with primers designed according to EST sequence in GenBank and used as probe for rice genomic library screening. In a screen of approximately 8.0×104 clones from the rice genomic library, sixteen positive clones were obtained, which strongly hybridized to the probe. One clone, E11, was selected for further analysis and the full-length 3661 bp rice epsps genomic sequence was obtained. Sequence analysis and homologous comparison revealed that epsps gene is composed of 8 exons and 7 introns. Analysis by restriction fragment length polymorphism with the probe of rice epsps cDNA fragment confirmed that rice epsps is located on chromosome 6 with an indica-japonica (ZYQ8-JX17) double-haploid (DH) population. This is the first report on the EPSP synthase from monocotyledons.展开更多
基金supported by Twelfth Five-Year Mega Project of Research on The Prevention and Control of HIV/AIDS,Viral Hepatitis Infectious Diseases 2013ZX10004-217 from the Ministry of Science and Technology,People’s Republic of China,the Project Sponsored by the Young Scholar Scientific Research Foundation of China CDC(No.2013A101)General Program of State Key Laboratory for Infections Disease Prevention and Control(No.2012SKLID205)
文摘The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.
文摘High affinity phosphate transporterplays an important role in plantadapting to low phosphorus. Isolationof genes coding this kind of proteinhas attracted worldwide scholars toaccomplish. We aimed to isolate thegene and transfer it to target plants
文摘Cytoplasmic male sterility(CMS) is a maternally inherited trait that results in the failure to produce functional pollen.It was identified in many plants,and it is widely used to exploit heterosis.
文摘Interspecific hybrids and constructed research models have provided infor-mation on intracellular interactions. We used two introgressed, chromosomally differentiated strains (H4 and H2) derived from F1 hybrids of crosses between D. prosaltans females and D. saltans males. In H4, the D. prosaltans chromosomes were eliminated. In H2, a mixture was maintained, preserving the entire genome of D. prosaltans (except the Y chromosome) and parts of the D. saltans genome. The IIR arm and a segment of chromosome III were eliminated. A third strain, used for comparison, was a normal D. prosaltans strain (P). This study aimed primarily to analyze the effect on the reproductive char-acteristics productivity (number of progeny) and sex-ratio caused by Wolbachia infection in interaction with different chromosome constitutions. For this, infected and uninfected flies were used in intrastrain cross combinations. Firstly, we analyzed the productivity of intracrosses of uninfected parents, in each strain, in order to detect the effects of intracellular interactions, in flies carrying different chromosome constitutions and sharing a Wolbach-ia-free, D. prosaltans cytoplasm. Data indicated that the chromosome parts that were eliminated, in H2, carry the isolating genes that impair productivity in hybrids of the two species, and suggested the occurrence of a nuclear/nuclear interaction. The analysis of Wolbachia-infected flies showed that the three strains presented different responses, depending on the chromosome constitution. As to productivity, the infection was harmful in P strain, in H2 behaved as mutualistic, and, in H4, produced the effect cytoplasmic incompatibility. As to sex-ratio, intracrosses showed significant differences in P and H4 strains. These results, associated with the cytological characteristics of the strains, pointed to the fundamental importance of host chromosome constitution to define the interactive process host/Wolbachia, and showed the flexibility of the endo-symbiont manifested in different forms of self-preservation.
基金This work was supported by the National High-Tech Program (863), National Natural Science Foundation of China (Grant Nos. 39989001, 39580012 & 39880023) National Special Program for Research and Industrialization of Transgenic Plants, and Rockefeller F
文摘The shikimate pathway enzyme 5-enolpyruvylshikimate 3-phosphate synthase (EPSPs) is the target of nonselective herbicide glyphosate. A partial rice epsps cDNA was generated by RT-PCR with primers designed according to EST sequence in GenBank and used as probe for rice genomic library screening. In a screen of approximately 8.0×104 clones from the rice genomic library, sixteen positive clones were obtained, which strongly hybridized to the probe. One clone, E11, was selected for further analysis and the full-length 3661 bp rice epsps genomic sequence was obtained. Sequence analysis and homologous comparison revealed that epsps gene is composed of 8 exons and 7 introns. Analysis by restriction fragment length polymorphism with the probe of rice epsps cDNA fragment confirmed that rice epsps is located on chromosome 6 with an indica-japonica (ZYQ8-JX17) double-haploid (DH) population. This is the first report on the EPSP synthase from monocotyledons.
