Fig. 4. Sens with a phosphomimetic mutation in linker 2 is able to induce bristle formation but does not bind the R21 probe. (A) EMSA assay using wild-type Sens and mutant Sens versions with phosphomimetic mutations in the linker regions that connect the Zn fingers. R21 oligonucleotide, to which Sens binds strongly, was used as probe. A phosphomimetic mutation in linker 1 (Sens-L1-S-E) reduces the Sens-DNA interaction. However, a phosphomimetic mutation in linker 2 (Sens-L2-T-E) does not show any DNA-binding activity under these conditions. The gel on the right shows 20% of the input for the mutant proteins and 20% of the wild-type Sens input is shown in Fig. 6E. (B,C) Ectopic expression of sens-L2-T-E using Eq-Gal4 driver induces formation of extra bristles at both 25°C and 28°C, as shown in B and C, respectively.