Structural requirements in full-length intron circularization. (A) Analysis of circularization of intron transcripts ending exactly in ωG. RNA transcripts corresponding to 5′-exon-intron (5′E-Int) of DiGIR2 and DiGIR2-ΔP9.2 were incubated under splicing conditions in time course experiments (0, 5, 15, 30, 60, 90, and 120 min), and subsequently separated on an 8 M urea/5% polyacrylamide gel. (B) The importance of the P1 segment in full-length circularization of DiGIR2. RNA transcripts corresponding to different P1 mutants were incubated under splicing conditions in time course experiments (0, 2, 5, 10, 20, 30, and 60 min), separated on an 8 M urea/5% polyacrylamide gel, and analyzed for full-length circle formation.
