Fig. 3. Analysis of the barley trnV intron lacking a bulged A in D6. (A) Sequence of mature exons and intron domains 5 and 6. Base numbering follows DDBJ/EMBL/GenBank database entry X00408. The tRNAVal(UAC) anticodon is underlined. The 5′ss and 3′ss are marked by solid lines. A broken line indicates intron domains 1–4. Intron nucleotides that showed linkage to the 5′ intron end in attempts to amplify lariat-specific cDNAs are boxed. (B) Detection of trnV splice precursor and products on northern blots hybridized with riboprobes specific for spliced tRNAVal(UAC) (cDNA probe) or intron sequences (intron probe). Precursor signals (P) of ∼670 nucleotides for 5′ and 3′ matured tRNA exons (Vogel et al., 1999) were obtained with both probes, whereas a set of smaller bands (I) was detected with the intron probe alone. Despite a smeary appearance, these intron-specific bands migrated at ∼600 nucleotides as calculated for released trnV intron.