Abstract
Based on the whole genome sequence of Mesorhizobium loti strain MAFF303099, we carried out large-scale analysis of protein-protein interactions by yeast two-hybrid (YTH) system. As the target for analysis, we selected M. loti genes whose up-regulation during symbiosis and microaerobiosis was revealed by the macroarray analysis and genes exist in symbiosis island. Furthermore, we also focused the interaction of the gene products conserved in other rhizobium species (Sinorhizobium meliloti and Bradyrhizobium japonicum), especially in the protein with unknown or regulatory function. At present, about 1000 bait clones have already been screened and over 1500 independent interactions consist of 1200 proteins were identified. In deduced large networks of M. loti proteins, we found various interactions of two component signal transducer and of symbiosis related gene with unknown function genes. Along with the YTH screening, the interaction database and its display system in RhizoBase are being prepared.
