An apparent non-canonical intron in the IGS1 R non-coding RNA.

A: 35 cycle RT-PCR across the apparent intron on cDNA synthesized with Superscript II and genomic DNA. cDNA was produced from a trf4Δ strain where this non-coding RNA is stabilized. B: Hairpin structure of IGS1 R, short homologous repeats are underlined in grey. C: 35 cycle RT-PCR across the apparent intron on trf4Δ cDNA synthesized using Superscript II at 42°C or Superscript III at 55°C. D: 35 cycle RT-PCR across the apparent intron on trf4Δ cDNA synthesized using Superscipt II or AMV. Control shows 30 cycle RT-PCR reaction across the ASC1 mRNA intron on the same cDNA samples.