Differential requirements for the O-linked branching enzyme core 2 beta1-6-N-glucosaminyltransferase in biosynthesis of ligands for E-selectin and P-selectin.
Selectins are carbohydrate-binding adhesion molecules that play important roles in control of leukocyte traffic. Glycosyltransferases involved in selectin ligand biosynthesis include the alpha1,3-fucosyltransferases FucT-VII and FucT-IV, one or more sialyltransferases, and at least one O-linked branching enzyme. Previous studies have shown that core 2 beta1-6-N-glucosaminyltransferase (C2GlcNAcT-I; EC 2.4.1.102) is required for functional modification of PSGL-1, the leukocyte P-selectin ligand, but have been ambiguous on whether this enzyme is involved in E-selectin ligand formation. Using an attachment and rolling assay under defined shear flow in vitro, this study shows that C2GlcNAcT-I(-) lymphoid cells stably transfected with FucT-VII complementary DNA attach and roll well on E-selectin at 1.5 dynes/cm.(2) Further, attachment and rolling on P-selectin of neutrophils is sharply reduced and that of short- term polarized Th1 cells is virtually abolished, with leukocytes from C2GlcNAcT-I(-/-) mice. In contrast, both neutrophils and Th1 cells from C2GlcNAcT-I(-/-) mice attach and roll as well as wild-type cells on E-selectin. These results show that C2GlcNAcT-I is selectively required for biosynthesis of ligands for P-selectin, but is not essential for at least some E-selectin ligands. Distinct requirements for C2GlcNAcT-I in the formation of ligands for E-selectin versus P-selectin represents a novel level of regulation of expression of selectin ligands and lymphocyte traffic. (Blood. 2001;97:3806-3811)
Snapp
K R
KR
Department of Microbiology-Immunology, Northwestern University Medical School, 303 E. Chicago Ave., Chicago, IL 60611, USA.
Heitzig
C E
CE
Ellies
L G
LG
Marth
J D
JD
Kansas
G S
GS
D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D019040:E-Selectin / Q000378:metabolism*; D005647:Fucosyltransferases / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D008024:Ligands; D008213:Lymphocyte Activation / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D017351:N-Acetylglucosaminyltransferases / Q000096:biosynthesis* / Q000378:metabolism / Q000494:pharmacology*; D009504:Neutrophils / Q000166:cytology / Q000502:physiology; D019007:P-Selectin / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D018417:Th1 Cells / Q000166:cytology / Q000502:physiology; D014162:Transfection
D019040:E-Selectin; D008024:Ligands; D019007:P-Selectin; D005647:Fucosyltransferases; D017351:N-Acetylglucosaminyltransferases; C063057:UDP-N-acetylglucosamine-peptide beta-N-acetylglucosaminyltransferase; C053024:beta-1,3-galactosyl-O-glycosyl-glycoprotein beta-1,6-acetylglucosaminyl transferase; C031692:galactoside 3-fucosyltransferase