Figure 1.

Comparison of human VEGFs with PDGFs and related sequences from Drosophila and Orf virus. Abbreviations: h, human; dm, Drosophila melanogaster, ov, Orf virus. (a) An alignment of the deduced amino-acid sequences of the VEGF/PDGF homology domain (VHD) from various human, Drosophila and Orf virus VEGFs and PGDFs. {online only} Sequence data were obtained from the GenBank and SwissProt databases; the multiple alignment was generated using MultAlin and further optimized manually. Residues that are conserved in at least 50% of the aligned sequences are shaded in green; those fully conserved are in yellow. The eight cysteine residues that constitute the cystine-knot structure [12] are denoted by asterisks below the sequences. (b) Predicted evolutionary relationships between human, Drosophila and Orf virus VEGFs and PDGFs. VHD sequences from (a) were aligned using ClustalW and the neighbor-joining method was used to construct a phylogenetic tree with TreeView. Branch lengths are proportional to the estimated evolutionary distance between protein sequences.