UASt regulatory sequences drive expression of a Hsap\SMN1 minigene that consists of exons 6 through 8 (including intervening introns). The pLUC coding sequence has been introduced at the C-terminal end of the exon 8 reading frame (to avoid interfering with exon 7 splicing). The translation start codon at the 5' end of the pLUC reporter has been modified by removing a single adenine nucleotide (preventing internal translation) and an additional nucleotide (G) has been placed after the 48th nucleotide of exon 7 to remove the native TAA translation termination codon. A functional pLUC reporter protein is only produced if exon 7 is included (if exon 7 is skipped, the reporter is out-of-frame) (details from PMID:11704813).