Expression in procephalic neuroblasts stage 9-11: tritocerebrum - d3, d5, v4, v5; deuterocerebrum - d5, d9, d13, v8; protocerebrum - ad3-10, av1, cv4, pd5, pd8
Expression of en-lacZ reporter delimits the segmental boundaries in the embryonic procephalic region of the ectoderm and labels a subset of neuroblasts during stages 9-11.
In third instar larval abdominal segments, expressed in the posterior compartment, in the posterior dorsal histoblast nest, and in a posterior subset of the cells in the ventral histoblast nests. In adult abdominal segments, expressed in the posterior compartment.
EcollacZen-Xho25 transcript was detected in the posterior compartments of imaginal discs, and in ocellus primordia.
In pupal wing, pattern slightly different that detected by antibodies against en protein. High level of expression in posterior compartment of the wing; in addition, a narrow region of faintly labelled cells immediately anterior to the posterior compartment, within the anterior compartment and widest at the distal tip of the wing.
Expression used as a marker for the posterior compartments of discs. The exact pattern was reported elsewhere. (FBrf0051823).
Homozygotes occasionally survive to adults (~1%).
Expression of lacZ in en pattern appears to be due to a combination of proximity of insertion to en gene and en regulatory sequences carried on the transposon.