Subfamily logos in comparison to classical sequence logos. Sections of three aquaporin subfamilies are shown, i.e. water/glycerol channels (GlpFs), water-specific channels (AQPs), and tonoplast intrinsic proteins (TIPs). Subfamily-specific residues are displayed upright, residues that are typical for the remaining sequences as tinted upside-down characters. The unit of the ordinates is in bits. Triangles mark known positions of relevant subfamily-specific deviations. Asterisks were computed by the subfamily logo algorithm to label subfamily-specifc residues.