A mercury biosensor was constructed by integrating biosensor genetic elements into E. coli JM109 chromosome in a single copy number, using the attP/attB recombination mechanism of λ phage. The genetic elements used i...A mercury biosensor was constructed by integrating biosensor genetic elements into E. coli JM109 chromosome in a single copy number, using the attP/attB recombination mechanism of λ phage. The genetic elements used include a regulatory protein gene （merR） along with operator/promoter （O/P） derived from the mercury resistance operon from pDU1358 plasmid of Serratia marcescens. The expression of reporter gene gfp is also controlled by merR/O/P. Integration of the construct into the chromosome was done to increase the stability and precision of the biosensor. This biosensor could detect Hg（Ⅱ） ions in the concentration range of 100–1700 nmol/L, and manifest the result as the expression of GFP. The GFP expression was significantly different （P 0.05） for each concentration of inducing Hg（Ⅱ） ions in the detection range, which reduces the chances of misinterpretation of results. A model using regression method was also derived for the quantification of the concentration of Hg（Ⅱ） in water samples.展开更多
Genetic diversity provides the foundation for plant breeding and genetic research.Over 3000 rice genomes were recently sequenced as part of the 3K Rice Genome(3KRG)Project.We added four additional Indian rice accessio...Genetic diversity provides the foundation for plant breeding and genetic research.Over 3000 rice genomes were recently sequenced as part of the 3K Rice Genome(3KRG)Project.We added four additional Indian rice accessions to create a panel of 3004 accessions.However,such a large collection of germplasm is difficult to preserve and evaluate.The construction of core and mini-core collections is an efficient method for the management of genetic resources.In this study,we developed a mini-core comprising 520 accessions that captured most of the SNPs and represented all of the phenotypes and geographic regions from the original panel.The mini-core was validated using different statistical analyses and contained representatives from all major rice groups,including japonica,indica,aus/boro,and aromatic/basmati.Genomewide association analyses of the mini-core panel efficiently reproduced the marker–trait associations identified in the original panel.Haplotype analysis validated the utility of the mini-core panel.In the current era with many ongoing large-scale sequencing projects,such a strategy for mini-core design should be useful in many crops.The rice mini-core collection developed in this study would be valuable for agronomic trait evaluation and useful for rice improvement via marker-assisted molecular breeding.展开更多
基金Director, Central Institute of Fisheries Education, Mumbaifor providing facility and financial assistance in the form of Masters’ Fellowship during the research period
文摘A mercury biosensor was constructed by integrating biosensor genetic elements into E. coli JM109 chromosome in a single copy number, using the attP/attB recombination mechanism of λ phage. The genetic elements used include a regulatory protein gene （merR） along with operator/promoter （O/P） derived from the mercury resistance operon from pDU1358 plasmid of Serratia marcescens. The expression of reporter gene gfp is also controlled by merR/O/P. Integration of the construct into the chromosome was done to increase the stability and precision of the biosensor. This biosensor could detect Hg（Ⅱ） ions in the concentration range of 100–1700 nmol/L, and manifest the result as the expression of GFP. The GFP expression was significantly different （P 0.05） for each concentration of inducing Hg（Ⅱ） ions in the detection range, which reduces the chances of misinterpretation of results. A model using regression method was also derived for the quantification of the concentration of Hg（Ⅱ） in water samples.
基金supported by the grants BT/AB/NIPGR/SEED BIOLOGY/2012 and BT/BI/04/069/2006 for the establishment of Distrib-uted Information Sub-Centre from the Department of Biotechnology,Gov-ernment of India.
文摘Genetic diversity provides the foundation for plant breeding and genetic research.Over 3000 rice genomes were recently sequenced as part of the 3K Rice Genome(3KRG)Project.We added four additional Indian rice accessions to create a panel of 3004 accessions.However,such a large collection of germplasm is difficult to preserve and evaluate.The construction of core and mini-core collections is an efficient method for the management of genetic resources.In this study,we developed a mini-core comprising 520 accessions that captured most of the SNPs and represented all of the phenotypes and geographic regions from the original panel.The mini-core was validated using different statistical analyses and contained representatives from all major rice groups,including japonica,indica,aus/boro,and aromatic/basmati.Genomewide association analyses of the mini-core panel efficiently reproduced the marker–trait associations identified in the original panel.Haplotype analysis validated the utility of the mini-core panel.In the current era with many ongoing large-scale sequencing projects,such a strategy for mini-core design should be useful in many crops.The rice mini-core collection developed in this study would be valuable for agronomic trait evaluation and useful for rice improvement via marker-assisted molecular breeding.
