UAS regulatory sequences drive expression of the RE28911 cDNA in which the SclA open reading frame has been replaced with the Hsap\PLN coding sequence, and which is also carrying insertion mutations after the start codon of the SclB open reading frame, resulting in a frameshift. The frameshift of SclB gives rise to a peptide of the same size but of a completely different sequence (MMRQKVCSPPSSSWPSCCSCSMPSTKAS) to wild type.