Not core 2 beta 1,6-N-acetylglucosaminyltransferase-2 or -3 but -1 regulates sialyl-Lewis x expression in human precursor B cells.
Sialyl-Lewis x (sLeX), one of the major selectin ligands, is expressed on T and B cells in a differentiation or activation stage-specific manner. We have demonstrated before that sLeX expression and core 2 beta 1,6-N-acetylglucosaminyltransferase (C2GnT) were simultaneously regulated during precursor B (pre-B) cell differentiation. Three C2GnT family genes, designated C2GnT-1, -2, and -3, were previously identified, but their roles have not been fully examined. In this study, we have investigated the roles of C2GnTs in the regulation of sLeX expression level during pre-B cell differentiation comparing with alpha 1,3fucosyltransferase-VII (FucT-VII) and alpha 2,3sialyltransferase-IV (ST3Gal-IV). Overexpression of not FucT-VII and ST3Gal-IV but C2GnT-1 blocked the down-regulation of sLeX expression by differentiation induction. Neither C2GnT-2 nor -3 but C2GnT-1 transcript was mainly expressed in B lineage cell lines and bone marrow-derived B lineage cells. Significant down-regulation of C2GnT-1 of the three C2GnTs was observed in KM3 cells during differentiation. The expression of C2GnT-1 correlated well to sLeX expression and differentiation stage. Furthermore, introduction of short interfering RNA against C2GnT-1 markedly reduced C2GnT-1 expression and resulted in down-regulation of sLeX expression. These results suggest that not the other glycosyltransferases but C2GnT-1 regulates sLeX expression level during differentiation of pre-B cells, providing the cells with substrate of sLeX structure biosynthesis.
Kikuchi
Jiro
J
Cell Regulation Analysis Team, Research Center for Glycoscience, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba 305-8562, Japan.
Shinohara
Hirotaka
H
Nonomura
Chizu
C
Ando
Hidenobu
H
Takaku
Shizuka
S
Nojiri
Hisao
H
Nakamura
Mitsuru
M
D000906:Antibodies / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D001853:Bone Marrow / Q000201:enzymology; D002454:Cell Differentiation; D002460:Cell Line; D019070:Cell Lineage; D005786:Gene Expression Regulation; D020868:Gene Silencing; D006801:Humans; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics / Q000378:metabolism*; D009844:Oligosaccharides / Q000235:genetics / Q000378:metabolism*; D000080506:Sialyl Lewis X Antigen; D013234:Stem Cells / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D014162:Transfection
D000906:Antibodies; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; D017351:N-Acetylglucosaminyltransferases; C053024:beta-1,3-galactosyl-O-glycosyl-glycoprotein beta-1,6-acetylglucosaminyl transferase