Ten copies of the UAS site followed by an Hsp70 basal promoter are fused upstream of a full-length Nos cDNA. A small intron derived from the Mhc gene followed by a synthetic AT-rich 21bp sequence has been inserted between the promoter and Nos sequences. The 3' UTR from the Autographa californica nucleopolyhedrovirus (AcNPV) p10 gene is present downstream of the Nos sequences.