MICROBODY DEFECTIVE-MUTANTS OF ARABIDOPSIS

In germinating fatty seedlings, microbodies are differentiated to leaf peroxisomes from glyoxysomes during greening, and then transformed to glyoxysomes from leaf peroxisomes during senescence. These transforma tions of microbodies are regulated at various level, such as gene expr ession, splicing of the mRNA and degradation of microbody proteins. In order to clarify the regulatory mechanisms underlying these transform ations of microbodies. we tried to obtain glyoxysome-deficient mutants of Arabidopsis. We screened 2,4-dichlorophenoxybutyric acid (2,4-DB) mutants of Arabidopsis which have defects in glyoxysomal fatty acid be ta-oxidation. Four mutants can be classified as carrying alleles at th ree independent loci, which we designated ped1, ped2, and ped3, respec tively (where ped stands for peroxisome defective), The characteristic s of these ped mutants are described.