Metabolic genome-wide association studies （mGWAS）, whereupon metabolite levels are regarded as traits, can help unravel the genetic basis of metabolic networks. A total of 309Arabidopsis accessions were grown under ...Metabolic genome-wide association studies （mGWAS）, whereupon metabolite levels are regarded as traits, can help unravel the genetic basis of metabolic networks. A total of 309Arabidopsis accessions were grown under two independent environmental conditions （control and stress） and subjected to untargeted LC-MS- based metabolomic profiling; levels of the obtained hydrophilic metabolites were used in GWAS. Our two- condition-based GWAS for more than 3000 semi-polar metabolites resulted in the detection of 123 highly resolved metabolite quantitative trait loci （p ≤ 1.0E-08）, 24.39% of which were environment-specific. Interestingly, differently from natural variation in Arabidopsis primary metabolites, which tends to be controlled by a large number of small-effect loci, we found several major large-effect loci alongside a vast number of small-effect loci controlling variation of secondary metabolites. The two-condition-based GWAS was fol- lowed by integration with network-derived metabolite-transcript correlations using a time-course stress experiment. Through this integrative approach, we selected 70 key candidate associations between struc- tural genes and metabolites, and experimentally validated eight novel associations, two of them showing differential genetic regulation in the two environments studied. We demonstrate the power of combining large-scale untargeted metabolomics-based GWAS with time-course-derived networks both performed under different ablotic environments for identifying metabollte-gene associations, providing novel global insights into the metabolic landscape of Arabidopsis.展开更多
Dear Editor, Tomato yellow leaf curl virus （TYLCV） is a whitefly-trans- mitted geminivirus infecting tomato crops （Czosnek, 2007）. TYLCV-resistant （R） and susceptible （S） lines with the same genetic backgroun...Dear Editor, Tomato yellow leaf curl virus （TYLCV） is a whitefly-trans- mitted geminivirus infecting tomato crops （Czosnek, 2007）. TYLCV-resistant （R） and susceptible （S） lines with the same genetic background have been bred using Solanum habro- chaites as the resistance source. The gene（s） conferring resist- ance are unknown. Previously, we demonstrated that the hexose transporter gene LeHT1 is up-regulated upon infec- tion in R plants and its silencing in R plants （RH） leads to the collapse of resistance （Eybishtz et al., 2010）. To uncover the role of LeHT1 in resistance, we （1） analyzed the transcriptome reprogramming in leaves of S, R, and RH plants using a home- designed microarray, before and 7 d after TYLCV inoculation （0, 7 dpi）, and （2） measured the concentration of sugars and their derivatives in S, R, and RH leaves at 1 and 7 dpi because LeHT1 is transporting both glucose and fructose （McCurdy et al., 2010）.展开更多
文摘Metabolic genome-wide association studies （mGWAS）, whereupon metabolite levels are regarded as traits, can help unravel the genetic basis of metabolic networks. A total of 309Arabidopsis accessions were grown under two independent environmental conditions （control and stress） and subjected to untargeted LC-MS- based metabolomic profiling; levels of the obtained hydrophilic metabolites were used in GWAS. Our two- condition-based GWAS for more than 3000 semi-polar metabolites resulted in the detection of 123 highly resolved metabolite quantitative trait loci （p ≤ 1.0E-08）, 24.39% of which were environment-specific. Interestingly, differently from natural variation in Arabidopsis primary metabolites, which tends to be controlled by a large number of small-effect loci, we found several major large-effect loci alongside a vast number of small-effect loci controlling variation of secondary metabolites. The two-condition-based GWAS was fol- lowed by integration with network-derived metabolite-transcript correlations using a time-course stress experiment. Through this integrative approach, we selected 70 key candidate associations between struc- tural genes and metabolites, and experimentally validated eight novel associations, two of them showing differential genetic regulation in the two environments studied. We demonstrate the power of combining large-scale untargeted metabolomics-based GWAS with time-course-derived networks both performed under different ablotic environments for identifying metabollte-gene associations, providing novel global insights into the metabolic landscape of Arabidopsis.
文摘Dear Editor, Tomato yellow leaf curl virus （TYLCV） is a whitefly-trans- mitted geminivirus infecting tomato crops （Czosnek, 2007）. TYLCV-resistant （R） and susceptible （S） lines with the same genetic background have been bred using Solanum habro- chaites as the resistance source. The gene（s） conferring resist- ance are unknown. Previously, we demonstrated that the hexose transporter gene LeHT1 is up-regulated upon infec- tion in R plants and its silencing in R plants （RH） leads to the collapse of resistance （Eybishtz et al., 2010）. To uncover the role of LeHT1 in resistance, we （1） analyzed the transcriptome reprogramming in leaves of S, R, and RH plants using a home- designed microarray, before and 7 d after TYLCV inoculation （0, 7 dpi）, and （2） measured the concentration of sugars and their derivatives in S, R, and RH leaves at 1 and 7 dpi because LeHT1 is transporting both glucose and fructose （McCurdy et al., 2010）.
