Related Experiment Video
Updated: Jul 15, 2026

Analysis of Physiologic E-Selectin-Mediated Leukocyte Rolling on Microvascular Endothelium
Published on: February 11, 2009
Normal cellular prion protein is a ligand of selectins: binding requires Le(X) but is inhibited by sLe(X)
Chaoyang Li1, Poki Wong, Tao Pan
1Institute of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH 44107-1712, U.S.A.
Abstract:
The normal PrP(C) (cellular prion protein) contains sLe(X) [sialyl-Le(X) (Lewis X)] and Le(X). sLe(X) is a ligand of selectins. To examine whether PrP(C) is a ligand of selectins, we generated three human PrP(C)-Ig fusion proteins: one with Le(X), one with sLe(X), and the other with neither Le(X) nor sLe(X). Only Le(X)-PrP(C)-Ig binds E-, L- and P-selectins. Binding is Ca(2+)-dependent and occurs with nanomolar affinity. Removal of sialic acid on sLe(X)-PrP(C)-Ig enables the fusion protein to bind all selectins. These findings were confirmed with brain-derived PrP(C). The selectins precipitated PrP(C) in human brain in a Ca(2+)-dependent manner. Treatment of brain homogenates with neuraminidase increased the amounts of PrP(C) precipitated. Therefore the presence of sialic acid prevents the binding of PrP(C) in human brain to selectins. Hence, human brain PrP(C) interacts with selectins in a manner that is distinct from interactions in peripheral tissues. Alternations in these interactions may have pathological consequences.
More Related Videos
10:16SorLA and CLC:CLF-1-dependent Downregulation of CNTFRα as Demonstrated by Western Blotting, Inhibition of Lysosomal Enzymes, and Immunocytochemistry
Published on: January 6, 2017
04:47Measuring Transcellular Interactions through Protein Aggregation in a Heterologous Cell System
Published on: May 22, 2020
Related Concept Videos
Selectins
Regulation of Nuclear Protein Sorting
Receptor-mediated Endocytosis
Ligand Binding Sites
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Immunoglobulin-like Cell Adhesion Molecules
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Assembly of Signaling Complexes
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...