Functional analysis of nuclear-genes for chloroplast development using albino mutants in Arabidopsis.

Abstract

To determine essential nuclear-genes involved in chloroplast development, we systematically analyzed albino or pale green Arabidopsis Ds-tagged knock-out mutants which was produced by using a two-component transposon system based on the Ac/Ds element of maize as mutagen. We have isolated about 40 mutants with albino or pale green (apg) phenotypes. Identified APG genes have sequence homology with house keeping proteins involved in photosynthesis, translation, transcription, translocation and so on. In this meeting, we present phenotypes of five apg mutants (apg3, apg4, apg5, apg11 and apg12), and discuss functions of the APG genes in chloroplast development.
To shed light on the regulation of plastid proteins during plastid differentiation, we also isolated intact chloroplasts, etioplasts and chromoplasts of wild type plants and apg mutant plastids by Nycodenz gradient centrifugation in Arabidopsis and tomato. We then analyzed plastid proteomic profiles in these different plastids.