In early egg chambers, more than 2 cells expressing marker are observed at each pole; progressively restricted to 2 cells at each; by stage S5, all restricted to precisely 2 cells at each pole.
Ecol\lacZ expression occurs incampaniform SMCs earlier than in the Ecol\lacZnrm-A37 line and is maintained inall sensillar cells through to adulthood. It is also expressed along thewing margin, in wing veins and in imaginal discs. It is expressed in theectopic sensilla that arise in the Hairy wing class of ac mutans, inother ac mutants and in h mutants.
The A101 enhancer trap line is one of the earliest markers for sensory mother cells in the imaginal wing disc (see FBrf0053759).
Enhancer trap expression occurs specifically in SMCs.