The residues proposed to be functionally important are mapped on to experimental structures. Blue—residues identified by mutational experiments, Yellow – exposed class-specific residues classified by ET in the trace 10, Red shows the overlap between ET and experimental mutations, Cyan – residues proposed to form cavities on the surface. (A) shows the WD part of G-beta protein (1GOT), (B) Transcriptional repressor Tup1 (1ERJ), (C) Transcriptional repressor Groucho (1GXR), (D) F-box/WD-repeat protein 1 (1P22), (E) Arp2/3 complex (1K8K), (F) Actin interacting protein 1 (1PGU), (G) Ski8p, mRNA degradation regulating protein (1SQ9). All proteins are oriented in an identical fashion.