Analyses of a Torenia Mutant Exhibiting a Class B-Function-Deficient Phenotype -For Determination of a Gene That Causes the Mutation Phenotype-

Abstract

We have applied heavy-ion beam irradiation to torenia for providing useful floral traits. Among them, we found a mutant (no. 252) that exhibited a B-function-deficient phenotype in which the organs in the second whorl were changed into sepals. RT-PCR analysis of the torenia class B genes revealed the TfGLO expression was abolished in the mutant. Because no effective mutation was found in the genomic sequence of TfGLO, we supposed the repression of TfGLO was caused by a defection of the upstream signaling. Since SQUA, LFY and UFO have been reported to participate in the expression of class B genes in Arabidopsis, we examined expressions of the torenia ortholog genes in the mutant. RT-PCR analysis revealed only TfUFO expression was diminished, and we found a mutation on TfUFO genome in the mutant.

This work was supported by the Programme for Promotion of Basic and Applied Researches for Innovations in Bio-oriented Industry.