Phosphatidic Acid Phosphatase 2B

Vascular endothelial growth factor and type I collagen inducible protein (VCIP), also known as phosphatidic acid phosphatase 2b (PAP2b), was originally identified in a functional assay of angiogenesis. VCIP/PAP2b exhibits an ArgÐGlyÐAsp (RGD) cell adhesion sequence. Immunoprecipitation and fluorescence-activated cell sorting analyses demonstrated that VCIP-RGD is exposed to the outside of the cell surface. Retroviral transduction of VCIP can induce cell aggregation and cellÐ cell interactions, modestly increase p120 catenin expression and promote activation of the Fak, Akt and GSK3§ protein kinases. Expression of VCIP promoted adhesion, spreading and tyrosine phosphorylation of Fak, Shc, Cas and paxillin in endothelial cells. PAP2b/VCIP is expressed in close proximity to vascular endothelial growth factor, von Willebrand factor and {alpha}v§3 integrin in tumor vasculatures.