Figure 2.

Kelch is stabilized upon mutation of all lysine residues to arginine. (A) Schematic of Drosophila Kelch protein, with locations of lysine residues indicated. The location of the Q109X lesion in kel^DE1 allele used in transgene rescue assays is also indicated. The allele truncates the protein before all functional domains. (B–E) Western analysis of protein levels from expression of the indicated mutant transgenes. cDNAs were expressed in the absence of endogenous Kelch using either weak (B, otuGal4) or strong (C, matGal4) germline drivers in a kelch null background. (D and E) Mean expression levels were measured relative to endogenous w¹¹¹⁸ control, and the expression level of the WT cDNA in each experiment was set at 1. (*) Statistically significant difference compared to WT cDNA expression level (P < 0.01, one-way ANOVA, Dunnett multiple comparison test). Error bars represent SEM. (F) Egg chambers immunolabeled to reveal Kelch level. Comparably staged egg chambers were imaged with identical exposure times to reveal differences in Kelch abundance. Scale bar, 50 µm.