Project description:The goal of this study was to calculate the degree of substantial equivalence between a GM potato line modified for late blight resistance and corresponding non-GM controls in the presence/absence of P. infestans inoculation. The GM phenotype was conferred through the introduction of the Rb gene which has been previously cloned from Solanum bulbocastanum (Song et al. 2003). The resulting GM phenotype was characterised by the expression of strong, partial resistance to P. infestans. By obtaining an expression profile from a GM and non-GM population before and after exposure to P. infestans, this effectively provides for the completion of two risk assessments: impact on the potato transcriptome of plus/minus genetic modification; before and after exposure to the pathogen. For each biological replicate, individuals from three separate GM lines (A, B, C) and three separate non-GM lines (D, E, F) were randomly sorted and cultivated for analysis. Each GM line contained an independent, single transgene insertion, which was verified through Southern Blot analysis. One day prior to pathogen exposure, the 4-week-old potato plants were transferred into a growth chamber with a 16-h light period, 90% relative humidity at a temperature of 15C. Plants were randomly selected and 14 individuals/line were inoculated with a field isolate of P. infestans. An additional 14 plants/line were sprayed with water. Inoculations were made with a sporangial suspension of 20,000/mL and plants were sprayed until run-off. Twenty-four hours post-inoculation, leaf tissue was collected from 9 plants per treatment, flash frozen in liquid nitrogen and pooled. Total leaf RNA was extracted using Trizol and the whole experiment was repeated three times (three biological replicates). Keywords: Direct comparison 19 hybs total
Project description:The goal of this study was to calculate the degree of substantial equivalence between a GM potato line modified for late blight resistance and corresponding non-GM controls in the presence/absence of P. infestans inoculation. The GM phenotype was conferred through the introduction of the Rb gene which has been previously cloned from Solanum bulbocastanum (Song et al. 2003). The resulting GM phenotype was characterised by the expression of strong, partial resistance to P. infestans. By obtaining an expression profile from a GM and non-GM population before and after exposure to P. infestans, this effectively provides for the completion of two risk assessments: impact on the potato transcriptome of plus/minus genetic modification; before and after exposure to the pathogen. For each biological replicate, individuals from three separate GM lines (A, B, C) and three separate non-GM lines (D, E, F) were randomly sorted and cultivated for analysis. Each GM line contained an independent, single transgene insertion, which was verified through Southern Blot analysis. One day prior to pathogen exposure, the 4-week-old potato plants were transferred into a growth chamber with a 16-h light period, 90% relative humidity at a temperature of 15C. Plants were randomly selected and 14 individuals/line were inoculated with a field isolate of P. infestans. An additional 14 plants/line were sprayed with water. Inoculations were made with a sporangial suspension of 20,000/mL and plants were sprayed until run-off. Twenty-four hours post-inoculation, leaf tissue was collected from 9 plants per treatment, flash frozen in liquid nitrogen and pooled. Total leaf RNA was extracted using Trizol and the whole experiment was repeated three times (three biological replicates). Keywords: Direct comparison
Project description:Phloem localization of plant viruses is advantageous for acquisition by sap-sucking vectors but hampers host-virus protein interaction studies. In this study, Potato leafroll virus (PLRV)-host protein complexes were isolated from systemically infected potato, a natural host of the virus. Comparing two different co-immunoprecipitation support matrices coupled to mass spectrometry, we identified 44 potato proteins and one viral protein (P1) specifically associated with virus isolated from infected phloem. An additional 142 proteins interact in complex with virus at varying degrees of confidence. Greater than 80% of these proteins were previously found to form high confidence interactions with PLRV isolated from the model host Nicotiana benthamiana. Bioinformatics revealed that these proteins are enriched for functions related to plasmodesmata, organelle membrane transport, translation and mRNA processing. Our results show that model system proteomics experiments are extremely valuable for understanding protein interactions regulating infection in recalcitrant pathogens such as phloem-limited viruses.
Project description:St (common potato) is a freezing sensitive species unable to cold acclimate. The close wild relative Sc is freezing tolerant and able to cold acclimate. Here we compare the cold transcriptome of these two species with different levels of freezing tolerance. We also identify the putative CBF regulons by comparing the transcriptomes of wild type plants with that of 35S::AtCBF3 transgenic lines in both species.
Project description:Potato wild relatives (Solanum section Petota) are a source of genetic diversity for improving traits in modern cultivars (S. tuberosum) to meet climate challenges. Potatoes are susceptible to multiple abiotic and biotic stresses and have undergone constant improvement through breeding programs worldwide. The allotetraploid S. acaule Bitter has been used to introgress cold tolerance into potato breeding germplasm. The cold challenged transcriptome of S. acaule was compared with that of autotetraploid S. tuberosum cv. Atlantic, and was found to have fewer differentially expressed genes than the latter. Specifically, subgenome 1 has less downregulated alleles compared to subgenome 2 and S. tuberosum.
Project description:The nutritional similarities between herbicide-tolerant genetically modified (GM) crops and non-GM counterparts are used as scientific evidence to show GM crops are substantially equivalent and safe and nutritious to non-GM. A previous study demonstrated substantial non-equivalence in ready-to-market soybeans obtained from 31 samples from Iowa, USA and discriminated GM, non-GM conventionally farmed and organic soybean. In the present study, by using high-resolution tandem mass spectrometry (HRMS) coupled with high-throughput proteomics and bioinformatic analyses, the same 31 individual soybean samples were investigated. Our results show that proteomic profiles of GM, conventionally, and organically farmed soybean samples were different. Differentially expressed proteins were found that can be used as markers to separate conventionally and organically farmed soybean seeds. Our data indicate that HRMS coupled with bioinformatic analyses provide a powerful platform to probe the equivalence of GM with non-GM material in food and feeding stuff.