Graduate School of Frontier Sciences, The University of Tokyo Department of
Integrated Biosciences

Plant diseases are a very good model for studying the interactions among the plants, microorganisms and vector insects. Analysis of the pathogenicity mechanisms of plant viruses will lead to the creation of disease-resistant plants, and the use of viruses as vectors will make them useful bio-resources.

We are interested in how a virus with only a few genes can induce plants diseases. Therefore, we are analyzing the gene expression of plant viruses and plant responses to them at the molecular level to elucidate the mechanism of disease. On the other hand, we are researching the use of viruses as a useful resource. Our current main research themes are as follows.

　How plant viruses cause plant diseases is still unclear. Interestingly, the fact that a single nucleotide difference in the gene of a virus can cause different diseases. Therefore, we are generating mutant viruses and identifying important nucleotide(s) sequences and/or amino acid(s) of viral genes.

　Virus vectors are used to insert foreign genes and express them in plants. And viral vectors that use RNA interference (RNA silencing), a phenomenon that suppresses gene expression mediated by specific RNA, suppress endogenous gene expression in plants. Therefore, it is possible to use viral vectors to analyze plant genes of unknown function.

　Currently, we are constructing viral vectors that suppress the expression of unnecessary genes in several legume species.