Alignment of vertebrate and invertebrate Iroquois protein sequences. Amino acid sequences were deduced from DNA sequences as summarized in Fig. 1, and designation of sequences is according to grouping of sequences therein. (A) Alignment of part of the N-terminal domain and the homeodomain (alignment positions 189–252). (B) Alignment of part of the C-terminal region encoding the conserved IRO box. Amino acids that are identical in more than half of the sequences are indicated by a solid box, and similar amino acids are indicated by a shaded box. ‘X’ denotes positions where the corresponding amino acids could not be identified from the DNA sequences; ‘−’ denotes positions where gaps have been introduced into the alignment; ‘x’ denotes gaps in the actual sequence assemblies. The complete alignment containing the entire N-terminal region and the homeodomain (1–256) is available from the authors on request.