HOS5, FRY2 and RS40/41 are required for pre-mRNA splicing.

<p>(A) and (B) Selected intron retention events in <i>hos5-1</i> (A) and <i>fry2-1</i> (B). Transcripts with splicing defects detected by RNA-seq are shown (Left panels). For each gene, annotated gene structures are presented (Top), with thick lines representing exons and thin lines representing introns. Wiggle plots representing the normalized read coverage in a logarithmic scale (log10) are shown in green for <i>hos5-1</i> mutant (middle) and in blue for C24 (Bottom). The red frames indicate the validated introns. Validation of the intron retention events in these 6 genes by RT-PCR are shown (right panels). The upper and lower bands represent the unspliced and spliced forms, respectively. (C) The common target of intron retention events in <i>hos5-1</i>, <i>fry2-1</i> and <i>hos5-1 fry2-1</i> double (<i>hos5 fry2</i>) mutants. The paradigms of six representative genes were shown and the checked introns were marked by fold lines. (D) Splicing defects in the <i>rs40-1 rs41-1</i> double (<i>rs40 rs41</i>) mutant. The paradigms of six representative genes were shown and the checked introns were marked by fold lines. The RT-PCR validation was performed and the upper and lower bands represent the unspliced and spliced forms, respectively.