Structure and function of the selectin ligand PSGL-1.
P-selectin glycoprotein ligand-1 (PSGL-1) is a dimeric mucin-like 120-kDa glycoprotein on leukocyte surfaces that binds to P- and L-selectin and promotes cell adhesion in the inflammatory response. The extreme amino terminal extracellular domain of PSGL-1 is critical for these interactions, based on site-directed mutagenesis, blocking monoclonal antibodies, and biochemical analyses. The current hypothesis is that for high affinity interactions with P-selectin, PSGL-1 must contain O-glycans with a core-2 branched motif containing the sialyl Lewis x antigen (NeuAc alpha 2-->3Gal beta 1-->4[Fuc alpha 1-->3]GlcNAc beta 1-->R). In addition, high affinity interactions require the co-expression of tyrosine sulfate on tyrosine residues near the critical O-glycan structure. This review addresses the biochemical evidence for this hypothesis and the evidence that PSGL-1 is an important in vivo ligand for cell adhesion.
Cummings
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RD
Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA. richard-cummings@uokhsc.edu
D001161:Arteriosclerosis / Q000378:metabolism; D002448:Cell Adhesion; D019040:E-Selectin; D006801:Humans; D037102:Lectins; D008024:Ligands; D008562:Membrane Glycoproteins / Q000502:physiology*; D009504:Neutrophils; D013329:Structure-Activity Relationship; D014443:Tyrosine
D019040:E-Selectin; D037102:Lectins; D008024:Ligands; D008562:Membrane Glycoproteins; C084882:P-selectin ligand protein; D014443:Tyrosine