This construct contains a 995-bp BamHI fragment upstream bus-1
(position 23,438 to 22,480 of cosmid R03H4)) cloned into MCSI of pPD49.26 vector. A 1.9-Kb KpnI-NcoI fragment was amplified from a bus-1
cDNA clone obtained from Open Biosystems (position 22,456 to 20,134). The resulting amplicon was subcloned into MCSII. The cDNA clone used as template did not contain any 3' UTR sequences.