Fig. 1. The identification of the complete open reading frames of zebrafish gfra1a, gfra1b and gfra2. (A) Alignment of the predicted amino acid sequence of zebrafish gfra1a, gfra1b and gfra2 with those of chick, mouse and human. Conserved amino acids between the different sequences are shown in red. The N-terminal, hydrophobic, putative signal peptides are underlined in green, the C-terminal hydrophobic domain is underlined in red, and the putative binding/cleavage sequences for GPI linkage are highlighted in yellow. (B) Unrooted phylogram of the Gfra protein family including the zebrafish orthologs. Multiple sequence alignments were made using the CLUSTALW program as part of the Biology Workbench package (http://workbench.sdsc.edu/) the unrooted phylogenetic tree was then generated from this alignment using the DRAWTREE application of the Biology Workbench that uses PHLYLIP version 3.5c.