
Type:Protein
Vascularendothelialgrowthfactor(VEGF),alsoknownasvascularpermeABIlityfactor(VPF)orvasculotropin,isahomodimeric34-42kDa,heparin-bindingglycoproteinwithpotentangiogenic,mitogenicandvascularpermeability-enhancingactivitiesspecificforendothelialcells.TheaminoacidsequenceofVEGFexhibitsprimarystructural,aswellaslimitedaminoacidsequence,homologywiththatoftheAandBchainsofPDGF.Alleightcysteineresiduesinvolvedinintra-andinter-chaindisulfidebondsareconservedamongthesegrowthfactors.ACDNAencodingaproteinhavinga53%aminoacidsequencehomologyinthePDGF-likeregionofVEGFhasbeenisolatedfromahumanplacentalcDNAlibrary.Thisprotein,namedplacentagrowthfactor(PlGF),isnowrecognizedtobeamemberoftheVEGFfamilyofgrowthfactors.BasedonitshomologywithVEGF,PlGFwasalsoproposedtobeanangiogenicfactor.TworeceptortyrosinekinaseshavebeendescribedasputativeVEGFreceptors.Flt-1(fms-liketyrosinekinase),andKDR(kinase-insert-domain-containingreceptor)proteinshavebeenshowntobindVEGFwithhighaffinity.