Characterization of the biosynthesis and cell surface expression of avian metapneumovirus attachment glycoprotein.
Biosynthesis, glycosylation and cell surface expression of the AMPV/C G protein were examined in eukaryotic cell lines (LLC-MK2, CHO-K1, CHO-1d1D). Immature G gene products with a molecular mass of 42, 45 and 58-90 kilodaltons (kDa) were identified by SDS-PAGE and represented glycosylated intermediates. Tunicamycin treatment of transfected cells confirmed the presence of N-linked carbohydrate moieties on these intermediate species and identified a 38 kDa unglycosylated precursor. A fully processed, mature form of the protein migrated around 110 kDa. The presence of O-linked sugars on the mature G protein was confirmed by using the O-glycosylation deficient CHO-ldlD cell line supplemented with exogenous Gal and GalNAc. Binding of the lectin Arachis hypogaea (peanut agglutinin) confirmed the presence of O-linked sugars on the mature protein and its intracellular transport to the cell surface was demonstrated by indirect immunofluorescent staining.
Luo
Lizhong
L
National Centre for Foreign Animal Disease, Winnipeg, Manitoba R3E 3M4, Canada. luol@inspection.gc.ca
Nishi
Krista
K
Liu
Li
L
Sabara
Marta I
MI
Li
Yan
Y
D000818:Animals; D010367:Arachis / Q000737:chemistry; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004591:Electrophoresis, Polyacrylamide Gel; D006031:Glycosylation; D037102:Lectins / Q000378:metabolism; D008253:Macaca mulatta; D029121:Metapneumovirus / Q000502:physiology*; D008970:Molecular Weight; D011485:Protein Binding; D011498:Protein Precursors / Q000737:chemistry / Q000302:isolation & purification; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D014764:Viral Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
D037102:Lectins; D011498:Protein Precursors; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C116204:attachment protein G