Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 4/5/2007
Publication Date: 7/7/2007
Citation: Doddapaneni, H., Lin, H., Takahashi, Y., Walker, A.M. 2007. Genome-Wide Profiling and Analysis of the Vitis Transcriptome Responses to Xylella fastidiosa Infection. American Society of Plant Biologists Annual Meeting. p. 89. Interpretive Summary:
Technical Abstract: The gram-negative bacterium Xylella fastidiosa (Xf), vectored by xylem-feeding sharpshooters, is the causal agent of Pierce’s disease (PD) in grape. This disease causes serious economic losses in California. PD resistant plants produced by conventional or molecular breeding techniques are the ultimate solution to this disease. However, information regarding genetic control of resistance and the molecular understanding of resistance mechanisms to PD is limited. Genome-wide transcriptional profiling using a custom high-density (382,900 probes) microarray chip of 20,020 Vitis transcripts from two highly resistant and highly susceptible sibling genotypes (Vitis rupestris x V. arizonica) for stem and leaf tissues have identified 5,299 differentially regulated transcripts. Differentially expressed transcripts reflecting spatial and temporal responses to PD involved in metabolic processes such as diseases resistance, water stress, photosynthesis and cell wall synthesis were identified. Mapping of these differentially regulated transcripts onto A. thaliana pathways identified regulatory points in the network and metabolic pathways involved in Grape/Xf interactions. This analysis has further identified 9 candidate genes (Flavonoid 3'-monooxygenase, Ferulate 5-hydroxylase, DIR1, MYB3R4, 9-cis-epoxycarotenoid dioxygenase, Zinc finger (CCCH-type) family protein, ERE-binding factor protien, LRR protein and Brassinosteroid-6-oxidase)which appear to be directly involved in the defense response at early, mid and late stages of Xf infection. RT-PCR analysis of 29 selected genes representing different affected metabolic pathways will be presented. In conclusion, the Vitis responses to Xf are genotype, tissue type, and developmental stage specific.