Comparative Analysis of Stilbene Synthase Genes Among Vitis Species

Stilbene synthase (StSy), encoded by a multigene family of several members, is the key enzyme to form resveratrol, the major component of the grapevine phytoalexin response. Genes encoding stilbene synthases have previously been described for several plant species including grapevine. Pierce’s disease (PD), anthracnose and downy mildew are the limiting factors for growing European grape (V. vinifera) in the southeastern United States. Native American grape species such as V. shuttleworthii, V. aestivalis and V. rotundifolia present strong resistance to these diseases. In order to understand the role of StSy in grapevine disease resistance, several hundred stilbene synthase gene sequences from among Vitis species were retrieved from the NCBI database. These stilbene synthase sequences were blasted against about 9,000 unigenes of V. shuttleworthii grape. Homologous relationships among the stilbene synthase (StSy 1) from five Vitis species were analyzed by multiple alignments