Homology plots of the Drosophila GNAT subunits dAda2a and dAda2b (A), dAda3 (C), dSpt3 (D), and dTra1 (E). (B) Unrooted phylogenetic tree generated with the CLUSTAL W (47) and PHYLIP (21) programs of the Ada2 homologues from various species (bootstrap value, 100; 15 repetitions). The distinct Ada2 variants from human, mouse, and Drosophila lie within the same branch (shaded ovals). Abbreviations: D.m., D. melanogaster; H.s., Homo sapiens; M.m., Mus musculus; A.t., Arabidopsis thaliana; Z.m., Zea mais; S.c., Saccharomyces cerevisiae; S.p., Schizosaccharomyces pombe; P.f., Plasmodium falciparum; C.o., Clavispora opuntiae; C.e., C. elegans; H.j., Hypocrea jecorina.