Construct: Alup\AFP1.5 3' untranslated sequences are replaced by Yp1 untranslated sequences.
A Yp2 promoter drives Alup\AFP1.9 expression.
Expression of a fragment carrying Alup\AFP1.9 transcription unit and 3' untranslated sequences is driven by the Yp2 promoter from a fragment of the Yp1-Yp2 intergenic region.