Figure 7. Analysis of chloroplast protein import efficiency in the tic22 double mutants.
A. Chloroplasts were isolated from 14-day-old, in vitro-grown plants of the indicated genotypes, and used in protein import assays with [35S]-methionine-labelled Rubisco SSU preprotein. Import was allowed to proceed for 3, 6 and 10 minutes, as indicated, and then samples were analysed by SDS-PAGE and fluorography. TM indicates an aliquot of the SSU translation mixture equivalent to 10% of the amount added to each assay; p and m indicate the precursor and mature forms of SSU, respectively. B. Mature protein bands observed in A were quantified using ImageQuant software, and then the data were expressed as percentages of the value for the final, wild-type time-point. These data, together with those from two additional, similar experiments, were used to calculate the mean (±SD) values shown (n = 3).