Figure 5.

RNA gel blot hybridization demonstrating a defect in rpl16 splicing in ppr5 mutants. Seedling leaf RNA from ppr5-1 mutants was compared to that in ppr103-2/-3 and ppr4-1 mutants. The ppr103 mutants lack both spliced and unspliced rpl16 RNAs due to a defect in stabilizing the processed 5′-end in the rpl16 5′-UTR (24). The ppr4-1 mutants are deficient for plastid ribosomes due to a defect in rps12 splicing (23). rRNA abundance is shown on the methylene blue stained blots below. The blot was probed to detect the second exon of rpl16. Transcripts were identified based on the data in Figure 3 and in (15).