Proceedings of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress
Giardini Naxos, Italy - 18/21 September, 2002
A BROAD APPROACH TO STUDY GRAPEVINE GENE EXPRESSION
MOSER C., GATTO P., SEGALA C., FONTANA P., PINDO M., VELASCO R.
Area Biologia Avanzata; Istituto Agrario S. Michele all’Adige, Via Mach 1, S. Michele all’Adige, Trento
grapevine, gene expression, ESTs, arrays, resveratrol
Gene expression analysis on a genome-wide scale has opened new possibilities to answer complex biological questions. The microarray technology and the high-throughput sequencing are the main technical bases of such a revolution in the experimental scale. In the last few years, though later than the human- and the biomedical-, also the plant biology field has been pervaded by this significant advance.
Grapevine (Vitis vinifera L.) is today one of the most widely cultivated and economically important crop due to its large adaptability to different climates and soils. As for most woody plants also for grape, gene expression studies are very limited in number and almost exclusively focused on one tissue, namely the berry. In order to gain novel insights at the molecular level into essential physiological processes like photosynthesis, plant defense and biosynthesis of secondary metabolites, we started one year ago a functional genomics project. Starting point was the construction of cDNA liraries from different grapevine tissues: leaf, inflorescence, sprout, bud, berry and root. Sequencing of clones randomly picked from the libraries has yielded up to now 1920 ESTs (Expressed Tagged Sequences) from inflorescence and sprout (cv. Regent) and 750 ESTs from leaf (cv. Pinot noir). The sequence information was then processed via bioinformatics tools in order to assign a putative function to each clone and to build a grapevine searchable database. In parallel, spotting of the amplified ESTs on to membrane filter or glass support will permit true genome-wide sampling of gene expression patterns. Preliminary experiments to compare the gene expression profiles in young, fully developed and senescent leaves by cDNA-macroarrays are under way.
Within the functional genomics project an important and complementary role is played by the development of differential cDNA libraries obtained by subtractive hybridization among cDNAs pools coming from different tissues or different cultivars. First goal of these experiments will be to highlight different transcript profiles between grapevine cultivars with high and low resveratrol content. Polyphenols are becoming more and more attractive for their properties in pharmacology and nutrition. Our purpose is then to dissect the metabolic pathways involved into their accumulation in plant tissues.