Gene expression profiling of the grape / Xylella fastidiosa Interaction

• Author(s): Lin, Hong;
• Abstract: The gram-negative xylem-limited bacterium Xylella fastidiosa is the causal agent of Pierces disease (PD) in grape. Resistance to PD exists in the grape germplasm, however information on PD resistance gene(s) and resistance mechanisms is limited. To understand the molecular basis of the grape-X. fastidiosa interaction, highly resistant and susceptible sibling genotypes from a V. rupestris x V. arizonica segregating progeny were inoculated with X. fastidiosa and 12 tissue-specific (stem, leaf and shoot) SSH cDNA libraries were constructed. We sequenced and annotated 5,794 PD-specific transcriptional profiles from which, 1,942 non-redundant ESTs were derived. About 54% of these ESTs did not match sequences in GenBank. Using Gene Ontology (GO) hierarchy, the non-redundant sequences were classified into: molecular function (30%), cellular components (9%) and biological processes (7%) categories, including known defense response genes. Our EST dataset was combined with 33,933 other Vitis ESTs (V. vinifera, V. shuttleworthii, V. rupestris 'A. de Serres' x V. arizonica, V. aestivalis and V. riparia) to generate a set of 20,020 non-redundant Vitis EST used to design a custom 60-mer high density (382,900 probes) microarray chip. Total RNA from early (1 week), mid (6 weeks) and late (10 weeks) stages of disease development from both infected and non-infected tissues of resistant and susceptible genotypes identified 9,089 transcripts that are significantly differentially regulated, with ~ 30% of those derived from our SSH libraries. Results of the 36 microarray slides suggest that differential responses to the X. fastidiosa infection are found in resistant and susceptible genotypes, infected and non-infected, and early and late stages.
• Publication Date: Aug 2006
• Journal: American Society Of Plant Biology