PRPF40A knockdown increases productive splicing of its spliceosomal binding partner LUC7L. (A) Summary of protein–protein interaction data (Ester and Uetz 2008) showing that yeast Prp40 directly interacts with yeast Luc7 via its first FF domain. (B) Mouse Luc7l gene model showing that if exon 2 is included, or if introns 1 or 2 are retained, then unproductive LUC7L is produced, lacking the region that interacts with Prp40, and containing premature stop codons likely to subject the transcript to NMD. (C) In control N2a cells, the majority of Luc7l is spliced into unproductive isoforms. (This is likely an underestimate, given that some unproductive mRNAs are likely destroyed by NMD.) Knockdown of PRPF40A, but not PRPF40B or SRRM4, results in strong increase of the productive isoform (exon 2 skipped and introns 1 and 2 spliced out). Numbers in parentheses represent PSI values for the replicate in question, and numbers over splice junctions indicate number of reads for that splice junction in the replicate in question.
