Amino acid replacement: S35A.
When ttk69.K46E.Scer\UAS is driven by Scer\GAL4Bx-MS1096, the number of dorsal chemosensory bristles in the triple row is reduced from ~ 18 in wild-type to ~ 7. The number of mechanosensory ventral triple row bristles is reduced to about 76 (compared to ~ 94).