Quantitative proteomics of isolated A. thaliana plastoglobules from wild-type, abc1k6-1 and Comp3

The quantitative proteomes of isolated plastoglobules have been determined from A. thaliana leaf chloroplasts at 4 weeks of growth using tandem mass spectrometry with label-free quantification. A comparison of three genotypes has been performed, namely i) the Col-0 wild type ecotype, ii) a T-DNA insertion mutant disrupting the plastoglobule-localized ABC1K6 protein (abc1k6-1) that is delayed in transition to reproductive growth, and iii) a complementation line (Comp3) that restores the timely progression of development with the ABC1K6 wild-type protein sequence tagged C-terminally with GFP in the abc1k6-1 background. The levels of ten plastoglobule proteins were found to be effected by the loss of ABC1K6. Of particular note, ABC1K7 was strongly depleted in abc1k6-1 and over-accumulated in Comp3, suggesting it may be stabilized by ABC1K6.