A NUCLEAR PHOTOSYNTHETIC ELECTRON-TRANSPORT MUTANT OF ARABIDOPSIS-THALIANA WITH ALTERED EXPRESSION OF THE CHLOROPLAST, PETA GENE

The nuclear photosynthetic mutant, hcf2, of Arabidopsis thaliana was i solated by screening M(2) seedlings for abnormally-high chlorophyll fl uorescence (hcf), indicative of a block in photosynthetic electron tra nsport. Fluorescence induction kinetics, photosynthetic electron trans port activity assays and immunoblotting revealed that all the complexe s involved in photosynthetic electron transport were affected to some extent. The most striking effect of the mutation was on the relative s teady state levels of the petA transcript (encoding the apoprotein of cytochrome f) which were more than five-times higher in the mutant pla nts than in their wild-type siblings.