Development of inflorescences in Arabidopsis thaliana

Those mutants were studied whose defects resulted in the morphological changes of inflorescences in Arabidopsis thaliana. We characterized newly isolated corymbosa mutants and acaulis5 mutants. The corymbosa1-1 mutation was caused by the defects in the elongation of pedicels and the previously identified erecta mutation belonged to this class. The corymbosa2-1 mutation was caused mainly by the increase of the number of the floral buds in the inflorescence. The expression of the ERECTA gene whose defect resulted to the corymbose inflorescence was analyzed. The ERECTA gene was expressed in subsets of cells in both the peripheral zone and central zone and was thought to have important role for the development of inflorescences. The phenotypes of the acaulis5 mutation was pronounced just after the transition from the vegetative to reproductive growth phase. We found that the expressions of the genes for EXGT-A1 and γ-TIP were drastically reduced in the acaulis5 mutants.