Figure 2.

Variability plots for homeodomains in different clades. The occurrence of different amino acid residues at each position was plotted for mammals (175 sequences that represent distinct genes), Drosophila (72 distinct sequences), C. elegans (80 distinct sequences), plants (70 sequences), and yeast (10 distinct sequences). The most conserved positions are positions 48 and 49, which belong to the core residues of the DNA-binding helix. With the exception of the low number of amino acids observable in yeast, the variability plots are very similar for metazoans and plants.