Fig. 1
From: Conservation and diversity of the eukaryotic SAGA coactivator complex across kingdoms
Schematic illustration of SAGA composition variations and function across kingdoms. Orthologues of yeast Spt8 is not found in higher eukaryotic SAGA complexes. Corresponding components of yeast Chd1/Arabidopsis CHR5 are not present in metazoans. Arabidopsis lack orthologues of yeast Sgf73/metazoan ATXN7. SF3B3 and SF3B5 components of the splicing module are not observed in yeast and not confirmed in Arabidopsis. PCAF can replace GCN5 specifically in vertebrates. In all eukaryotes, SAGA catalyzes acetylation (Ac) and removal of ubiquitylation (Ub) on histone tails and interacts with transcription factors (TFs), activating transcription of target genes to further regulate biological outcomes in development, stress response, immunity and disease. SAGA can also acetylate and deubiquitylate TFs to affect their stability and activity