Fig. 1

Alternative splicing of penultimate exons frequently extends the ORF into the 3′UTR. a Schematic representation of the identification of exon skipping events that allow translation into the 3′UTR. b Pie-chart showing validation of candidates by RNA-seq data for transcripts with stop codon in penultimate (light red: validated, light gray: not validated) or ultimate exon (red: validated, dark gray: not validated). c Two-dimensional tSNE plot showing tissue-specific penultimate exon skipping pattern using 22 mouse tissues. d tSNE plot showing neuronal differentiation stage specific penultimate exon skipping pattern. DIV, days in vitro. e Distribution of minimum (PSI_MIN), median (PSI_MEDIAN), mean (PSI_MEAN), and maximum (PSI_MAX) PSI values across different mouse tissues for penultimate exons that are alternatively spliced in at least one tissue (candidates from b) with RNA-Seq support), either for all exons or divided into annotated and novel isoforms