Pseudocowpox virus Encodes a Homolog of Vascular Endothelial Growth Factor

AbstractWe have identified a gene encoding a homolog of vascular endothelial growth factor (VEGF) in the Pseudocowpox virus (PCPV) genome. The predicted protein shows 27% amino acid identity to human VEGF-A. It also shows 41 and 61% amino acid identity to VEGFs encoded by orf virus (ORFV) strains NZ2 and NZ7, respectively. Assays of the expressed VEGF-like protein of PCPV (PCPVVR634VEGF) demonstrated that PCPVVR634VEGF is mitogenic for endothelial cells and is capable of inducing vascular permeability. PCPVVR634VEGF bound VEGF receptor-2 (VEGFR-2) but did not bind VEGFR-1 or VEGFR-3. These results indicate that PCPVVR634VEGF is a biologically active member of the VEGF family which shares with the ORFV-encoded VEGFs a receptor binding profile that differs from those of all cellular members of the VEGF family. It seems likely that the biological activities of PCPVVR634VEGF contribute to the proliferative and highly vascularized nature of PCPV lesions