P{Mae-UAS.6.11} insertion a few nucleotides upstream of the first exon of ab. The P{Mae-UAS.6.11} element is oriented such that overexpression from the Scer\UAS regulatory sequences within it (using a Scer\GAL4 driver) drive overexpression of ab.
Expression of B2149B2149 under the control of Scer\GAL4dpp.blk1 results in a transformed arista, severe leg defects and an abnormal number of macrochaetae.
Expression of abB2149 under the control of Scer\GAL4dpp.blk1 results in a transformed arista which grows out as a short tube-like structure, which resembles the legs of these mutants, which are also abnormal. These flies do not eclose. The notum has supernumerary macrochaetae.