Project description:The use of profiling techniques such as transcriptomics, proteomics, and metabolomics has been proposed to improve the detection of side effects of plant breeding processes. This paper describes the construction of a food safety-oriented potato cDNA microarray (FSPM). Microarray analysis was performed on a well-defined set of tuber samples of two different potato varieties, grown under different, well-recorded environmental conditions. Data were analyzed to assess the potential of transcriptomics to detect differences in gene expression due to genetic differences or environmental conditions. The most pronounced differences were found between the varieties Sante and Lady Balfour, whereas differences due to growth conditions were less significant. Transcriptomics results were confirmed by quantitative PCR. Furthermore, the bandwidth of natural variation of gene expression was explored to facilitate biological and/or toxicological evaluation in future assessments. Keywords: experiment with factorial design factorial design; 2 potato cultivars (Sante, Lady Balfour); 2 fertilizers (dairy manure compost, chicken manure pellets); 3 plant protection treatments (copper oxychloride, comcat, water), 3 biological replicates, 48 samples
Project description:Analyses of new genomic, transcriptomic or proteomic data commonly result in trashing many unidentified data escaping the ‘canonical’ DNA-RNA-protein scheme. Testing systematic exchanges of nucleotides over long stretches produces inversed RNA pieces (here named “swinger” RNA) differing from their template DNA. These may explain some trashed data. Here analyses of genomic, transcriptomic and proteomic data of the pathogenic Tropheryma whipplei according to canonical genomic, transcriptomic and translational 'rules' resulted in trashing 58.9% of DNA, 37.7% RNA and about 85% of mass spectra (corresponding to peptides). In the trash, we found numerous DNA/RNA fragments compatible with “swinger” polymerization. Genomic sequences covered by «swinger» DNA and RNA are 3X more frequent than expected by chance and explained 12.4 and 20.8% of the rejected DNA and RNA sequences, respectively. As for peptides, several match with “swinger” RNAs, including some chimera, translated from both regular, and «swinger» transcripts, notably for ribosomal RNAs. Congruence of DNA, RNA and peptides resulting from the same swinging process suggest that systematic nucleotide exchanges increase coding potential, and may add to evolutionary diversification of bacterial populations.