A. Splicing-sensitive microarrays contain probes that target precursor (P), mature (M), and total (T) mRNA levels. B. Global splicing profiles of the snt309Δ and lsm6Δ strains, showing a strong splicing defect for both mutants. C. Global splicing profiles of the mud2Δ and cus2Δ strains, illustrating different splicing defects for these mutants. Whereas many transcripts show a splicing defect in the mud2Δ strain, many continue to be efficiently spliced. Similarly, most intron-containing genes show no splicing defect in the cus2Δ strain. D. The behavior of specific transcripts in the different mutant backgrounds. E. Locations within the U3 precursor dataset of the mutant strains for which microarrays are shown in (B) and (C).