Current Researchers: R. N. Beachy, S. Dai, M. Ordiz
Previous Researchers: S. Petruccelli, Y.Yin, Y. Liu, Z. Zhang

Gene function is mediated via structural RNA or the proteins encoded by messenger RNA. The gene functions together determine the nature of the cells and tissues that comprise the organism. Because thousands of genes work in concert to effect cell growth and metabolism, gene expression must be closely regulated. Gene expression is controlled by highly complex interactions between the associated regulatory proteins, the target DNA sequences, and RNA polymerase complexes.

Understandably, strategies that regulate gene expression can be used to reduce the impact of certain virus diseases; if the expression of viral genes can be limited, viral diseases can be controlled.

Research in Roger Beachy's Laboratory addresses gene expression of a plant virus called rice tungro bacilliform badnavirus (RTBV) that causes significant crop loss in Asia. This virus possesses a promoter sequence that is responsible for expression of viral genes and thus for virus infection in plants. The group has discovered that the expression initiated by the viral promoter sequence is activated by proteins present in rice phloem cells including two unique proteins, RF2a and RF2b. These proteins are also involved in expression of genes in phloem cells.

The lab is developing transgenic rice and tobacco plants that contain mutants of RF2a protein that lack certain domains responsible for activating expression from the virus promoter. They have found some mutants that restrict expression from the promoter.

The group aims to determine the nature of the interactions between the proteins DNA and the protein to protein interactions that control expression from the promoter. The long-term goal of the research is to limit replication of RTBV in transgenic rice plants.

Selected recent publications pertaining to gene regulation: