Natural variation in RPS2-mediated resistance: correlating gene-expression profiles to phenotypic responses.

ABSTRACT: Natural variation within plant species is an important resource for discovery of genes controlling biological traits. Gene-expression profiling of natural variation is increasingly used to identify genes affecting a trait. Here, we explored variation among Arabidopsis thaliana accessions with respect to defense against Pseudomonas syringae pv. tomato DC3000 (Pst), with a focus on R-gene mediated resistance triggered by the Pst type III effector protein AvrRpt2. We explored variation at two phenotypic levels: growth of the bacteria and hypersensitive response (HR) measured by electrolyte leakage. Considerable variation among accessions was found at both phenotypic levels. The genetic variation among accessions affected both growth of Pst with (Pst avrRpt2) and without (Pst) the AvrRpt2 effector, with some variation being specific for the bacterial strains, and other variation affecting both strains in a similar manner. Variation in HR was not correlated with variation in bacterial growth. Additionally we examine variation in gene-expression profiles after mock- and Pst avrRpt2-inoculated plants, obtained using a dedicated microarray Gene-expression profiling at 6 h post inoculation identified clusters of genes from which expression levels are correlated with bacterial growth and electrolyte leakage. The expression levels of some of these clusters correlate with more than one phenotypic characteristic, such as growth of both Pst and Pst avrRpt2, whereas other clusters were correlated with just one biological parameter. Thus we demonstrate that variation in gene-expression profiles among Arabidopsis accessions is correlated with variation in phenotypic responses. Keywords: Comparisons of Arabidopsis thaliana accessions with respect to inoculation with Pseudomonas syringae pv tomato avrRpt2.

ORGANISM(S): Arabidopsis thaliana

PROVIDER: GSE8298 | GEO | 2007/08/09

SECONDARY ACCESSION(S): PRJNA101261

REPOSITORIES: GEO