Figure 3.

Helical RNA structures joining the 5′ and 3′-terminal regions of mitochondrial large subunit rRNAs. In the three given examples, the RNA termini have been determined experimentally at single-nucleotide resolution (Lang et al., 1987; Lang et al., 1997). The RNA termini are either adjacent to, or within a few nucleotide positions outside the helical region. Note the lack of significantly conserved sequence motifs and the variability of helix shape and length, which renders in-silico identification of the termini difficult.