The goal of this project is to develop a new tool for functional genomics based on the gene silencing phenomenon known as RNA interference (RNAi). A particular form of RNAi, known as Sense-RNAi, will be optimized for use as a focused genomics tool with special application in crop plants. The method will produce a series of individual plants, in each of which a single gene has been silenced. By screening a population of Sense-RNAi silenced plants, investigators will be able to identify genes that contribute to valuable traits of particular interest to the investigator. By using Sense-RNAi rather than standard RNAi approaches, it is expected that silencing transgene constructs will be produced very efficiently. This will allow silencing to be focused on a select subset of the genes in a crop plant, increasing dramatically the overall efficiency of identifying genes that affect a given trait. This new technology will be developed, tested and optimized in a model plant species and then applied to crop plants, beginning with tomato. The gene silencing method will be focused on genes expressed in trichomes, which are tiny hairs on the surface of a leaf that help protect the plant from insects and microbes. The expected outcome of the funded project is primarily the optimized method for silencing of a focused set of genes, including the necessary plant transformation vectors and experimental protocols for successful application of this method to crop plants. Results will be disseminated through publications and via a user's manual that will be posted on the web and updated as needed. Vectors will be provided to users without restriction via a public repository, which we anticipate will be ABRC.
