Nucleic Acids Research, 2006, Vol. 34, No. 3 963 Figure 4. Amino acid clusters of activators. (A–E) Amino acid clusters indicating the maximum number of the respective amino acid in a window of 20 amino acids of the protein (For the remaining amino acid clusters see Supplementary Figure 2). (F) Minimum isoelectric point (pI) in a 20 amino acids window, summarizing the effect of charged amino acids (glutamate, aspartate, arginine, lysine). YDR520C, also localized to the cytoplasm and the nucleus, was shown to bind a zinc ﬁnger-containing transcriptional repressor, Dal80 (27), suggesting the interesting hypothesis that Dal80 is repressing the activator properties of YDR520C. YGL066W/SGF73, a protein with unknown molecular function, was identiﬁed as a novel subunit of the SAGA (Spt/Ada/Gcn5 acetylase) multisubunit complex (50). Ataxin-7 is the human ortholog of the yeast SAGA SGF73 subunit and is a bona ﬁde subunit of the human TFTC- like transcriptional complexes (TATA-binding protein-free TAF-containing complex) (51). The physical association of YGL0066W with the TFTC transcription complex and its activation properties supports a role in transcriptional regulation function.