FIGURE 5.

Analysis of the region upstream of Y69A2AR.18. The genomic arrangement of Y69A2AR.18 is similar to that of K01C8.6 and nduf-5. It is located ∼1.6 kb downstream from Y69A2AR.19, and the gene Y69A2AR.21 lies between these genes on the opposite DNA strand. Gels of overlapping RT-PCRs indicate that RNA is not transcribed in the region between Y69A2AR.18 and the nearest upstream gene, Y69A2AR.19. Instead, RNA from this gene has a defined outron. The first step gel and RNA deep sequencing data show that Y69A2AR.18 mRNA is preferentially SL1 trans-spliced, as would be expected in a nonoperon gene. The RNA identified in the fourth step RT-PCR is consistent with a termination product of the upstream gene, as has been previously observed (Haenni et al. 2009).