This construct contains two elements. First, UAS regulates expression of a dsRNA corresponding to a 72bp non-contiguous region on exon 2 of RpL14, that targets endogenous RpL14 transcripts for RNAi-mediated knock-down. Second, a complete RpL14 genomic region (called "RpL14[r]") containing 14 synonymous mutations in exon 2 which confer insensitivity to the RNAi induced by the first element. The genomic region includes fragments of flanking genes to help ensure that all regulatory regions are included, and two intronic snoRNAs.