Mutations of the N'' (NLKNAL), N' (NSRNAD) and N (NEANERL) motifs to Ala residues.
Expression of m4NNN2.Scer\UAS.T:Zzzz\FLAG under the control of Scer\GAL4sca-537.4 does not result in the production of extra bristles (total of 26 bristle positions on the notum and head assayed).