A stop codon has been introduced just N-terminal to the D motif (DRWVQA) normally found at the C-terminus of m4.
Expression of m4D.Scer\UAS.T:Zzzz\FLAG under the control of Scer\GAL4sca-537.4 results in the production of extra bristles (average 29 extra bristles per fly, total of 26 bristle positions on the notum and head assayed).