At 12h APF, EcollacZ^ap-rK568 drives expression in one row of cells in the developing lamina, that co-expresses bsh protein. In adults, EcollacZ^ap-rK568 drives expression in lamina monopolar neuron L4, co-localising with bsh and dac.

EcollacZ^ap-rK568 transcript is expressed in both male and female genital discs of third instar larvae. Expression is more extensive and at a higher level in male than in female discs.

The expression of ey, ap, and Dll were compared in outer optic lobes (OPC) starting in late third instar larvae. At this stage they were expressed as three distinct cell populations. In anterior sections, the three genes are expressed a three parallele stripes of cells that represent rows of neurons that emerge from the OPC. They correspond to progeny from the youngest to oldest neuroblasts. In middle sections, Dll-positive cells are generated in the progeny of the oldest neuroblasts, with ey-positive and ap-positive cells often placed below Dll-positive (in cells that had emerged earlier from the these neuroblasts). By the beginning of pupation, the number of cells origination from the OPC increased. A major reorganization of optic lobe structure occurs around P20 such that the three stripes are no longer distinguishable and the three cell populations are extensively interspersed within the adult medulla cortex.

EcollacZ^ap-rK568 drives expression in the lamina monopolar L4 neurons and in 40% of the cells in the medulla cortex. Cells labeled with EcollacZ^ap-rK568 do not overlap with cells expressing ScerGAL4^ey-OK107 or ScerGAL4^Dll-md23.

EcollacZ^ap-rK568 is expressed in approximately 10 of the ~350 neurons in each hemisegment of the first instar larval ventral nerve cord. In each of the six thoracic hemisegments and in the third subesophageal hemisegments, EcollacZ^ap-rK568 is expressed in four or five cells.

EcollacZ enhancer trap expression isobserved in larval and pupal imaginal discs. Expression is observedthroughout the parts of the of the wing and haltere discs that give riseto the dorsal surface of the wing and haltere blades, at lower levels inthe regions that form the notum and scutellum, and at the highest level inthe wing hinge region. Expression is also observed in the presumptivefourth tarsal segment of the ventral thoracic discs, in a central spot inthe antennal portion of the eye antennal disc, and in the larval brain.EcollacZ expression can not be detected in the female germ line, the fatbody, or in Malpighian tubules.