Figure 10.

Import of pre-atTic110 into Isolated Chloroplasts from atTic110N_His and atTic110C_His Plants.

(A) In vitro–translated (IVT) Arabidopsis [³⁵S]pre-atTic110 was incubated with chloroplasts from wild-type, atTic110N_His, and atTic110C_His plants in the presence of 5 mM ATP. Equivalent samples of each reaction were removed at the indicated time points, and the chloroplasts were reisolated through 40% Percoll. The chloroplasts were analyzed directly by SDS-PAGE and phosphor imaging. The positions of pre-atTic110 and atTic110 are indicated at the right.

(B) Quantitative analysis of the protein import assays in (A). The amount of imported mature [³⁵S]atTic110 was calculated as a percentage of the total [³⁵S]pre-atTic110 in vitro translation product added to each reaction. Each graph represents the mean of three experiments, with bars indicating standard error. IM, inner membrane; OM, outer membrane.

(C) Accumulation of soluble [³⁵S]atTic110 during the time course of import. A portion of each time point sample in the import reactions in (A) was extracted with alkaline buffer, and the soluble fraction was recovered by trichloroacetic acid precipitation. Samples were analyzed by SDS-PAGE and phosphor imaging.

(D) Quantitative analysis of the soluble [³⁵S]atTic110 in (C). The amount of soluble mature [³⁵S]atTic110 was calculated as a percentage of the total [³⁵S]pre-atTic110 in vitro translation product added to the original import reaction. Each graph represents the mean of three experiments, with bars indicating standard error.