Fig. 1. Sequence alignment, genetic structure and family homology of putative zebrafish ß4GalT5. (A) Sequence alignment of zebrafish, human and mouse ß4GalT5 proteins. Identical sequences are shaded in red. Conserved cysteines used to align sequences are boxed in blue and predicted sugar-nucleotide binding sites are boxed in red. (B) Predicted gene structure of ß4galt5. Exons are boxed, introns indicated by dashed lines. Arrows indicate conserved cysteines and the solid line above exon 1 indicates the predicted signal sequence and transmembrane domain; sugar-nucleotide binding motifs are also indicated (Lo et al., 1998). (C) Unrooted phylogenetic tree of human (h) and zebrafish (dr) ß4GalTs (drß4GalT5, red).