Construct: The Alup\AFP1.5 intron has been deleted and replaced with the Yp1 intron.
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.