Abstract
In higher plants, peroxisomes are subdivided functionally into glyoxysomes, leaf peroxisomes and unspecialized peroxisomes. We extensively surveyed gene expression profile of peroxisomal proteins in various organs of Arabidopsis thaliana. In seedlings, genes of glyoxysomal proteins were expressed. In green cotyledons and rosette leaves, genes of leaf peroxisomal proteins were expressed. These results agree with the previous reports and indicate that our data of gene expression profile was reliable in categorizing functional profiles of peroxisomal genes. In our results, a group of genes that encoded peroxisomal proteins with unknown function were expressed specifically in roots. It suggests that peroxisomes in roots are functionally differentiated from those in other organs. One of the genes expressed in roots encoded putative polyamine oxidase. GFP fusion protein of the gene product was localized in peroxisomes. We discuss function of the root peroxisomes in Arabidopsis thaliana based on the analyses of peroxisomal polyamine oxidase.
