Fig. 1. Chico PH, PTB, Drk, and PI 3-kinase effector mutants. (A) The chico genomic rescue construct and the corresponding PH, PTB, Drk, and PI 3-kinase effector consensus site mutants. Numbers indicate amino acid positions (not drawn to scale). (B) The PI 3-kinase, PH and PTB consensus sites are critically required for Chico function in body size control, while the Drk consensus site is dispensable. The weight of male flies carrying the various transgenes was measured as described by Böhni et al. (Böhni et al., 1999). (C) The PTB domain is not required for Chico control of female fertility. The number of pupae that developed from eggs laid by an equal number of females of the indicated genotype is shown. (D) All the Chico effectors, except Drk, function in the control of lipid metabolism. All assays were performed three times on at least 10 flies.