Functional interaction of dGcn5 and dAda2a. (A) Yeast two-hybrid assay indicates strong interaction between dAda2a and dGcn5. Constructs tested for interaction contained fusions (DNA-binding domain in pBTM and acidic activation domain in pGAD424) as follows: 1, dAda2a-none (negative control); 2, dRpb4-dRpb7 (positive control); 3, dAda2a-dAda3; 4, dAda2b-dAda3; 5, dAda2a-dGcn5; and 6, dADA2b-dGcn5. (B) The null dGcn5E333st mutation has a negative effect on the development of dAda2ahyp1. The phenotype change is shown as the fraction of animals reaching the adult (A), pharat adult (PhA), and early pupa (EP) stages in the wild-type (light gray bars) and dGcn5 heterozygous background (white bars). (C) The overexpression of dGcn5 from a transgene (dark gray bars) has a positive effect on the development of dAda2ahyp2 (labels are as described in panel B). The inserts show the fractions of adults displaying the outstretched wing (os, white) and wild-type (wt, black) phenotypes. Resulting from the different chromosomal background (see Materials and Methods), the fractions of dAda2ahyp1 and dAda2ahyp2 adults in the two experiments (columns in panel B and C) are different. Error bars indicate deviations.