Figure 1

An Oct1 orthologue in catfish. A. Megalin (DNAStar) amino acid alignment of Oct1 proteins. Conserved residues are shaded by grey boxes. The boxed portion indicates the bipartite POU DNA binding domain. Glutamine rich regions are denoted by arrows and text Gln1 or Gln2. Serine and thrionine rich residues are denoted by arrows and S/T rich. The linker region is also designated by text. Gaps in the sequence alignment are indicated by a dash. B. Schematic comparing the domain structure of Oct transcription factors. N- and C- terminal domains are shown as checkered boxes, POU domains are shown hatched with diagonal lines, and the linker region is shown as a black box. The percent identity values (derived using the Megalign program, DNAStar) are based on the amino acid sequences and are shown below the schematic. C. Neighbor joining phylogenetic tree [49] of Oct1 and Oct2 transcription factor sequences (see Methods). The C. elegans homeobox gene was used as the outgroup. The three branches for Oct1, Oct2 and the invertebrate Oct sequences are indicated by brackets, and the bootstrap value for each node is shown.