Expression of glycosylated mucin-like domain using baculovirus expression system in silkworm, bombyx mori

Baculovirus expression systems (BES) are widely used for recombinant protein production in lepidopteran cells or larvae. It is known that insect cells have a glycosylation pathway similar to that of mammalian cells. Thus, BES are possible to be used to produce recombinant proteins with higher eukaryotic modifications. In insect cells, the Af-glycosylation pathway has been well-researched. However, the O-glycosylation pathway is poorly understood. In this study, we expressed a partial recombinant HsPRG4 (rPRG4) as a reporter for O-glycosylation and investigated whether BES in silkworm could produce the proteins with mucin-like clustered O-glycans. Analysis by SDS-PAGE and glycosidase digestion indicated that rPRG4 had Core 1 and Core 2 O-glycan chains. These results suggested that BES could produce the protein containing mucin-type O-glycosylation in Bombyx mori. baculovirus expression system, Bombyx mori, O-glycosylation.