Expression cloning of a functional glycoprotein ligand for P-selectin.
The initial adhesive interactions between circulating leukocytes and endothelia are mediated, in part, by P-selectin. We now report the expression cloning of a functional ligand for P-selectin from an HL-60 cDNA library. The predicted amino acid sequence reveals a novel mucin-like transmembrane protein. Significant binding of transfected COS cells to P-selectin requires coexpression of both the protein ligand and a fucosyltransferase. This binding is calcium dependent and can be inhibited by a neutralizing monoclonal antibody to P-selectin. Cotransfected COS cells express the ligand as a homodimer of 220 kd. A soluble ligand construct, when coexpressed with fucosyltransferase in COS cells, also mediates P-selectin binding and is immunocrossreactive with the major HL-60 glycoprotein that specifically binds P-selectin.
Sako
D
D
Genetics Institute, Small Molecule Drug Discovery Group, Cambridge, Massachusetts 02140.
Chang
X J
XJ
Barone
K M
KM
Vachino
G
G
White
H M
HM
Shaw
G
G
Veldman
G M
GM
Bean
K M
KM
Ahern
T J
TJ
Furie
B
B
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D016466:CHO Cells; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary / Q000378:metabolism; D004730:Endothelium, Vascular / Q000502:physiology; D015723:Gene Library; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute; D007962:Leukocytes / Q000502:physiology; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000378:metabolism; D008969:Molecular Sequence Data; D019007:P-Selectin; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D014407:Tumor Cells, Cultured
D015815:Cell Adhesion Molecules; D018076:DNA, Complementary; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins; D019007:P-Selectin; C084882:P-selectin ligand protein; D010980:Platelet Membrane Glycoproteins