Project name: Nicotiana tabacum

Description: Determination of fitness for viral genotypes is a standard practice in virology an essential to evaluate their evolutionary potential. Darwinian fitness, defined as the advantage of a given genotype respect to a reference one, is a macroscopic property that captures into a single figure differences in performance at every stage of viral infection. To which extent the expression of certain host genes determines viral fitness? Can we identify host’s genes whose expression have a significant effect on viral fitness? To which functional classes and regulatory networks do belong these genes? We compared the transcriptomes of tobacco plants infected with seven genotypes of tobacco etch potyvirus (TEV) that differ in fitness. The larger the fitness differences among genotypes, the more dissimilar the transcriptomic profiles are. Some genes were significantly altered by all genotypes while others depend on viral fitness. We identified genes whose expression showed a positive correlation with TEV fitness and genes with a negative one. To validate these correlations, we analyzed the expression of four positively and five negatively correlated genes. Over-expression of the first group activates hormone-mediated plant defense pathways. Under-expression of the second group reduces metabolism, growth and development and/or plant viral resistance, resulting in higher susceptibilityOverall design: All six TEV mutant genotypes used in this study (HC-Pro:AS13, HC-Pro:CLA2, HC-Pro:CLA11, CI:PC48, CI:PC55 and NIb:PC95 genotypes) were constructed by successive rounds of site-directed mutagenesis starting from template plasmid pMTEV. N. tabacum L. cv. Xanthi NN plants were used for production of a large stock of virus particles for each of the genotypes (including WT). At given dpi virus-infected leafs and apexes for each plant were collected individually. Total RNA was isolated and hybridized onto a genotypic designed N. tabacum Gene Expression 4×44K Microarray (AMADID: 021113), which contained 43,803 probes (60-mer oligonucleotides) and was used in a one-color experimental design. Three biological replicas for each viral genotype infected plant, wild-type infected plants and mock-inoculated plants were analyzed.

Data type: Transcriptome or Gene expression

Sample scope: Multiisolate

Relevance: Agricultural

Last updated: 2017-06-08