A 66bp RpL27A promoter fragment (contains both a M1BP protein-binding site and a Opbp protein-binding site) drives expression of a transcription unit composed of the RpS28b 5'UTR, the pLUC coding sequence and the RpS28b 3'UTR. An SV40 polyadenylation signal is present upstream of the RpL27A promoter fragment, so isolate it from nearly promoters when this transgene is inserted in the genome.