624bp HpaI fragment of Ecol\lacZ coding sequences is ligated in frame to the HpaI site of orb D5 cDNA. 2.6kb HindIII orb genomic fragment containing the last 1000 bases of the orb 3' UTR and 1.6kb of genomic sequences downstream replaces the 3' UTR of the orb cDNA. Expression is driven by an Hsp83 promoter.