Cloning and characterization of mouse vascular adhesion protein-1 reveals a novel molecule with enzymatic activity.
Human vascular adhesion protein-1 (VAP-1) is a sialylated endothelial cell adhesion molecule mediating the initial L-selectin-independent interactions between lymphocytes and endothelial cells in man. In this work we cloned and characterized mouse VAP-1 (mVAP-1) and produced an anti-mVAP-1 mAb against a recombinant mVAP-1 fusion protein. The isolated cDNA encodes a novel 84.5-kDa mouse molecule. The anti-mVAP-1 mAb stained high endothelial venules in peripheral lymph nodes, and smooth muscle cells and lamina propria vessels in gut. During immunoblotting, this anti-mVAP-1 mAb recognized a 110/220-kDa Ag, suggesting that mVAP-1 is a dimer. Since mVAP-1 has significant sequence identity to members of a family of enzymes called the copper-containing amine oxidases, we showed that mVAP-1 possesses monoamine oxidase activity. Thus, mVAP-1 is the first mouse membrane-bound amine oxidase identified at the molecular level. Based on the 83% identity between the isolated cDNA and human VAP-1 cDNA, the expression pattern, the molecular mass, and the enzyme activity against monoamines, the cloned molecule represents a mouse homologue of human VAP-1. Cloning of mVAP-1 provides a valuable tool for in vivo studies of the significance of VAP-1 for lymphocyte-endothelial cell interactions and of the possible relationship between leukocyte adhesion and amine oxidase activity.
Bono
P
P
MediCity Research Laboratory, University of Turku, Finland. petbon@utu.fi
Salmi
M
M
Smith
D J
DJ
Jalkanen
S
S
D006631:Amine Oxidase (Copper-Containing) / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D000588:Amines / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D001483:Base Sequence; D016466:CHO Cells; D015815:Cell Adhesion Molecules / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D006224:Cricetinae; D018076:DNA, Complementary / Q000302:isolation & purification; D019281:Dimerization; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D008198:Lymph Nodes / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D008970:Molecular Weight; D051381:Rats; D017386:Sequence Homology, Amino Acid
D000588:Amines; D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules; D018076:DNA, Complementary; C076668:AOC3 protein, human; D006631:Amine Oxidase (Copper-Containing)