Publications [#113153] of Harold P. Erickson

Papers Published

1. S Ushiyama, TM Laue, KL Moore, HP Erickson, RP McEver, Structural and functional characterization of monomeric soluble P-selectin and comparison with membrane P-selectin., The Journal of biological chemistry, UNITED STATES, vol. 268 no. 20 (July, 1993), pp. 15229-37, ISSN 0021-9258
   (last updated on 2009/02/12)

   Abstract:
   P-selectin is an adhesion receptor for leukocytes on thrombin-activated platelets and endothelial cells. It contains a NH2-terminal carbohydrate-recognition domain, an epidermal growth factor motif, nine consensus repeats, a transmembrane domain, and a cytoplasmic tail. We expressed two soluble forms of P-selectin, one truncated after the ninth repeat (tPS) and the other lacking the transmembrane domain due to alternative RNA splicing (asPS). When visualized by electron microscopy, each was a monomeric rod-like structure with a globular domain at one end, whereas membrane P-selectin (mPS) from platelets formed rosettes with the globular domains facing outward. Sedimentation velocity and equilibrium studies confirmed that tPS and asPS were asymmetric monomers, whereas mPS was oligomeric. HL-60 cells adhered to immobilized tPS and asPS, although less efficiently than to mPS. 125I-Labeled tPS and asPS bound to approximately 25,000 sites/neutrophil and approximately 36,000 sites/HL-60 cell with an apparent Kd of 70 nM. Treatment of HL-60 cells with O-sialoglycoprotease eliminated the binding sites for asPS. We conclude that 1) P-selectin is a rigid, asymmetric protein; 2) monomeric soluble P-selectin binds to high affinity ligands with sialylated O-linked oligosaccharides on leukocytes; and 3) oligomerization of mPS enhances its avidity for leukocytes.

   Keywords:
   Alternative Splicing • Amino Acid Sequence • Base Sequence • Binding Sites • Cell Adhesion • Cell Adhesion Molecules • Cells, Cultured • DNA • Humans • Microscopy, Electron • Molecular Sequence Data • Neutrophils • P-Selectin • Platelet Membrane Glycoproteins • Protein Conformation • Recombinant Proteins • Solubility • chemistry • isolation & purification • metabolism • physiology* • ultrastructure