Figure 5.

A cis-spliced group II intron is identified in Asplenium nidus by using PCR amplification with the nad5 b/c primer set. The intron and its trans-arranged homologues in wheat (25), Arabidopsis, and Oenothera show certain divergences from the group II intron consensus, such as the unusual ACC 3′ terminus, an additional nucleotide (U) between the conserved GA dinucleotide and the domain III stem, and noncanonical domain I substructures. Denotion of intron features is as in Fig. 2. The nad5 sequence of Asplenium nidus is deposited in the data bases under accession no. Y07912Y07912.