Abstract
In a virescent mutant of rice, the seedling has initially yellow-colored leaves that are less chlorophyll, and then the color of leaves gradually becomes more greenish as the mutant grows. The mutable virescent plant, pyl-v (pale yellow leaves variegated) showed yellow leaves with green sectors, and the variegation was caused by recurrent somatic mutation from the recessive pyl-v allele to the green Pyl-r (Pyl-revertant) allele. We showed that the pyl-v allele is caused by the disruption of nuclear-coded chloroplast protease gene, OsClpP5 due to an insertion of a novel transposon. The insertion affects the selection of transcription initiation site that result in OsClpP5 mRNA lacking its first initiation codon. The defects of grana stacks in chloroplasts of yellow leaves, did not recovered even after they become green. Phenotypic features in pyl-v mutant with regard to the expression of OsClpP5 gene will be discussed.
