Figure 2.

Gene organization and encoded functional domains of the human VEGF genes and related genes from Drosophila. Exons, represented by boxes, are numbered and the length of coding sequence in each is marked below in base-pairs. Start (ATG) and stop (TAA, TAG, TGA) codons are marked, and the length of each encoded unprocessed polypeptide including the signal peptide (in amino-acid residues) is indicated in parentheses. Exons are drawn to scale, except for the last exon of hVEGF-A, which is longer than 1 kilobase (kb). Introns, represented by horizontal lines, are not drawn to scale. Alternative exons and splicing patterns are not shown, with the exception of hVEGF-B, in which isoforms result from alternative splicing of exon 6 [23]. Arrows represent proteolytic cleavage sites. Abbreviations: 3', 3' untranslated region (UTR); 5', 5' UTR; CP, region encoding the carboxy-terminal propeptide domain; H, encodes the heparin-binding domain; N, encodes the NRP1/heparin-binding domain; NP, encodes the amino-terminal propeptide domain; SP, signal peptide; VHD, encodes the VEGF/PDGF homology domain. Information was compiled from published literature [14-16,22,23,59-61] and the Entrez Gene, RefSeq, GenBank and SwissProt databases.