Site specific mutations in the intracellular roles of asparagine-linked oligosaccharides

The β subunit of human chorionic gonadotropin containing asparagine ( ) - linked oligosaccharides. A review of thestructure and function, these oligosaccharide unit in vivo, we constructed mutants containing genes change orasparagine or threonine codon glycosylation consensus sequences, insertion into the eukaryotic expression vector.Wild type and the mutant protein expressed in Chinese hamster ovary cells alone or in the presence of local alpha subunits. Pulse-chase analysis of beta-expressing clones showed, no two N connected sugar but not the first slowsecretory 1.6-1.8-fold; none of the two N decreased secretion of 2-2.4-fold unit. Analysis of two poly clonal shows,more than 80% of native and glycosylation mutant subunit two dimer secretion. However, pulse-chase analysis of these clones also showed, mutant completely lacking N - sugar but not single site mutations is slow andαsubunitassembly. Therefore, in vivo N-linked oligosaccharides of gravity center measuring is crucial for the efficient secretion and assembly of the alpha subunit, may be important for the proper folding of the governance of βsubunit.