SGER: Development of Tandem RNAi for Silencing of Gene Families in Rice

Dartmouth College, Hanover NH

Investigators

Abstract

PI: G. Eric Schaller, Dartmouth College CoPIs: Joseph J. Kieber (University of North Carolina-Chapel Hill) and Pamela Ronald, (University of California, Davis) A major challenge to analyzing the roles of genes in plants has been the discovery that many genes are present in gene families. Due to functional overlap (genetic redundancy) among the members of a gene family, multiple family members must thus be disrupted in order to ascertain their function and to modify their role in the plant. To overcome genetic redundancy, we propose a novel approach to disrupt multiple genes simultaneously within a plant, accomplishing this by means of a tandem array of RNAi targeted to multiple genes within a family. This project will develop and test this "supersilencing" system in the monocot rice. For this purpose, both constitutive and inducible versions of the vectors will be made. Three gene families involved in signaling by the plant hormones cytokinin and ethylene will be targeted for disruption. Transgenic lines containing the supersilencing constructs will be characterized using molecular and physiological methods to assess the success of the approach. Broader impacts: The success of the supersilencing approach would result in the establishment of a new genetic tool for the study and modification of genetically controlled traits in rice and other monocot crop species. This approach would enable rapid modification of genes and pathways instrumental to the improvement of traits of agronomic importance such as yield, abiotic and biotic resistance, stress responses, and biomass. Vectors for use in supersilencing will be made available to the plant research community. The proposed research will enhance the infrastructure of research and education by providing hands-on training for project undergraduate students and graduate students.