EcollacZ reporter gene expression wasobserved in <12 hr adults in the prefrons. After 12 hrs, expression isobserved in the funiculus and sacculus of the third antennal segment andat the posterior border of the second antennal segment. By 72 hrs, theentire third antennal segment and the proximal part of the maxillary palpsare stained. 3-5 day old flies show staining in epithelial cells of thesalivary glands especially in the posterior portion. Male-specificexpression was observed 1-3 days after eclosion in the ejaculatory bulb ina region surrounding the apodema and in epithelial cells of theejaculatory duct. The tracheae of the air sacs of the head, thorax, andlegs stain in flies 2 days or older. Respiratory system expression is moreintense in older flies (3-5 days old) but is confined to trachea and airsacs of the head and thorax.