Premium
Biosynthesis of sialylated and fucosylated selectin ligands of HL‐60 cells in vitro
Author(s) -
Natunen Jari,
Parmanne Pinja,
Helin Jari,
Aitio Olli,
Majuri Marja-Leena,
Niemelä Ritva,
Renkonen Risto,
Renkonen Ossi
Publication year - 1999
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(99)00638-9
Subject(s) - fucosylation , chemistry , in vitro , selectin , biosynthesis , biochemistry , stereochemistry , fucose , microbiology and biotechnology , biology , glycoprotein , enzyme , adhesion , organic chemistry
Polylactosamines Neu5Acα2‐3′Lexβ1‐3′Lexβ1‐3′Lex and Neu5Acα2‐3′LNβ1‐3′Lexβ1‐3′Lex [Lex, Galβ1‐4(Fucα1‐3)GlcNAc; LN, Galβ1‐4GlcNAc] decorate selectin counterreceptors in human HL‐60 cells. Here, we show that HL‐60 cell lysates catalyze distal α3‐sialylation of LNβ1‐3′LNβ1‐3′LN and LNβ1‐3′Lexβ1‐3′Lex efficiently, outlining two potential sets of biosynthetic pathways leading to the selectin ligands. In one set, α3‐sialylation precedes internal fucosylation of the polylactosamine backbone, whereas in the other one, internal fucosylation is initiated before α3‐sialylation. In contrast to α3‐sialylation, LNβ1‐3′Lexβ1‐3′Lex was α6‐sialylated much less efficiently than LNβ1‐3′LNβ1‐3′LN by HL‐60 cell lysates. Hence, internal fucosylation may regulate the extent of α6‐sialylation of polylactosamines in these cells.