Ecol\lacZbrk-X47 is expressed in dpp-negative cells positioned in the inner proliferation zone of the larval optic anlage.
Ecol\lacZbrk-X47 is expressed in the wing disc from the anterior edge to several cell diameters anterior to the outer edge or presumptive wing vein L2, and from presumptive wing vein L5 to the posterior edge of the disc.. brk expression is complementary to that of bi.
Enhancer trap expression is observed at the anterior and posterior extremes of the wing disc. It is also detected in a gradient along the anterior-posterior axis in the wing pouch. In dpp mutants, expression is ubiquitous in the disc.