Purpose
This project is to develop a high-throughput RNAi-mediated gene silencing system for soybean (Glycine max) functional genomics study. The research result is expected to provide “a proof-of-concept” that RNAi technology can be used as an efficient tool for systematically assigning gene functions in soybean.

Objectives
The Objectives for the first year is to 1. Design and construct dsRNAi constructs that allow efficient silencing of soybean genes; 2. Construct plant transformation vectors that enable RNAi technology and a high-throughput cloning process. The completion of these two objectives will lay a foundation for objectives 3 and 4. In objectives 3 and 4, transgenic soybean lines will be developed using Agrobacterium-mediated transformation and those transgenic lines will be analyzed both molecularly and phenotypically for ascertaining RNAi-mediated gene silencing.

Process
Today all the intermediate vectors (entry vectors) and  most transformation constructs (destination vectors) have been made which incorporate Gateway Cloning technology and various designs as proposed to be tested. These designs will test our working hypotheses to improve RNAi efficacy. All the reverted repeats of soybean ESTs have been PCR-amplified and inserted into these constructs for RNAi tests. Immediately after these final constructs are mobilized into the Agrobacterium and confirmed for their integrity, the soybean transformation experiments will start. Molecular and phenotypic analyses will follow once transgenic soybean lines have been developed.

Impact
The completion of this project will lay a good foundation for verifying functions of numerous soybean genes and have a profound impact on engineering of this crop for genetic improvement to improve both research and the U.S. economy. Genome-wide functional assignment of soybean genes employing RNAi technology and ESTs will validate useful genes that will become invaluable resources immediately available for genetic improvement of soybean for value-added traits.