Time course of changes in <i>psbA</i> ribosome occupancy and protein synthesis following light shifts in maize seedlings.

<p>(A) Kinetics of ribosome loss on <i>psbA</i> following a shift to dark. Plants were processed for ribosome profiling at the indicated time points following a shift to the dark at midday. The 10-minute time point was performed in two replicates; the mean ± SEM is shown. Other time points were performed once. However, the 0 and 60 minute time points are equivalent to the triplicated data shown in preceding figures, which gave similar values. (B) <i>In vivo</i> pulse labeling following light-to-dark shifts. Labeling with ³⁵S-methionine/cysteine was initiated at the indicated times and continued for 15 min. Total leaf lysates were analyzed by SDS-PAGE and phosphorimaging. The two rapidly synthesized proteins at ~100 kDa are likely to be the nuclear gene products PEP Carboxylase and PPDK.