Fig. 3

Comparison of the rpl23, clpP, and 3′ rps12 gene clusters in land plant plastids. Genes shown on the upper part are encoded on the + strand and genes shown on the lower part are encoded on the - strand. Closed boxes indicate exons and open boxes indicate introns. The left column shows the rpl23 operon. The dark brown color indicates inverted repeats (IR) and blue color indicates the large single-copy region (LSC). The middle column shows the clpP operon. Platycodon has an clpP operon structure with a trace of exons and introns. Other known Campanulaceae species have lost the clpP operon structure by genomic rearrangement. The right column shows the 3′ rps12 operon. trnV_gac precedes the 3′ rps12 operon in Platycodon and most land plants, but other known Campanulaceae species have lost this arrangement