Figure 2.

Sequence comparison of nine bHLH-PAS domain proteins. The schematic diagram (Middle) shows the canonical organization of bHLH-PAS domain proteins. Amino acid sequences shown above correspond to the bHLH domains, sequences shown below correspond to the PAS-A and PAS-B domains. Individual amino acid sequences were obtained using the Entrez sequence retrieval system (National Center for Biotechnology Information). Shaded amino acids, designated consensus, represent residues identical among seven or more of the nine proteins analyzed. Numbers in parentheses after designation of each protein (Left) represent the residue number at which each sequence starts relative to the initiator methionine of the relevant protein.