Plant & Animal Genomes XI Conference Plant & Animal Genomes XI ConferenceJanuary 11-15, 2003
Town & Country Convention Center
San Diego, CA
Poster: Genome Sequencing & ESTs
Grapevines exposed to water deficit stress produce berries with altered metabolite and glucan composition with little loss in fruit quantity. We are taking an integrated functional genomics approach to understand how changes in gene expression resulting from abiotic stress impact metabolite changes that improve color, aroma, and flavor components of berries and wine. cDNA libraries were prepared from mRNA isolated from leaves, berries, and roots of Vitis vinifera L. cv. Chardonnay exposed to cold, heat, salt, water deficit, and low-oxygen stress treatments. Berries from water deficit stressed vines were harvested at seven different developmental stages. Approximately equal numbers of cDNA clones were randomly selected and sequenced from leaf, root and berry libraries for a total of 18,000 ESTs. Sequences analysis revealed that ~53%, ~59%, ~85% of ESTs from leaf, berry, and root libraries, respectively, were novel or were similar to genes with unknown function. Overall, approximately 11% of ESTs were related to disease/defense or abiotic stress adaptation. The leaf library contained significantly more photosynthesis-related genes than either berry or root libraries, whereas the berry library had significantly more ESTs with secondary metabolism, fruit ripening and flowering related genes than the leaf and root libraries. Full-length cDNA libraries and oligonucleotide-based microarrays are under construction to facilitate future mRNA and protein expression profiling studies. Gene expression data will be integrated with metabolite profiles to develop a global picture of abiotic stress effects in Vitis vinifera that will lead to improvements in grape production efficiency and wine quality.