Mutation of the N motif (NAANEKL to AAAAAAA) and of the N' motif (DNLRNAQVE to DAAAAAAVE).
Expression of mαNN.Scer\UAS under the control of Scer\GAL4sca-537.4 does not result in the production of a significant number of extra bristles (total of 26 bristle positions on the notum and head assayed).