Abstract
Japanese gentian (Gentiana triflora and G. scabra) is one of the popular floricultural plants in Japan. One of the breeding aims in Japanese gentian is floral morphologic modification, but a few available morphologic mutants exist in nature. Model plant researches have demonstrated that MADS box genes play important roles in floral organ identifications. Therefore, we attempted to isolate and characterize MADS box genes from Japanese gentian plants using degenerate PCR technology. As the result, 14 candidates of MADS box genes were isolated from flower bud cDNAs of G. scabra and then classified into each class by phylogenetic analysis. Spatial expression analysis showed that the expression of each gentian MADS box gene was detected at the corresponding floral whorls. In B-class genes, however, the expression of GsGLO1 to 3 were restricted to petal and stamen, whereas those of GsDEF1 and GsDEF2 were detected in all whorls. Yeast two-hybrid analysis showed that GsGLO2 interacts with GsDEF1 and GsDEF2. We produced the transgenic tobacco and Arabidopsis plants introduced with gentian MADS box genes, and the analysis is in progress.
