Title |
Defining the N-Linked Glycosylation Site of Hantaan Virus Envelope Glycoproteins Essential for Cell Fusion |
Author |
Feng Zheng1, Lixian Ma1, Lihua Shao2, Gang Wang1, Fengzhe Chen1, Ying Zhang1, and Song Yang1 |
Address |
1Qilu Hospital of Shandong University, Jinan, Shandong province, 250012, China, 2School of Public Health of Shandong University, Jinan, Shandong province, 250012, China |
Bibliography |
Journal of Microbiology, 45(1),41-47, 2007,
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DOI |
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Key Words |
Hantaan virus, cell-cell fusion, glycoproteins, N-linked glycosylation |
Abstract |
The Hantaan virus (HTNV) is an enveloped virus that is capable of inducing low pH-dependent cell fusion. We molecularly cloned the viral glycoprotein (GP) and nucleocapsid (NP) cDNA of HTNV and expressed them in Vero E6 cells under the control of a CMV promoter. The viral gene expression was assessed using an indirect immunofluorescence assay and immunoprecipitation. The transfected Vero E6 cells expressing GPs, but not those expressing NP, fused and formed a syncytium following exposure to a low pH. Monoclonal antibodies (MAbs) against envelope GPs inhibited cell fusion, whereas MAbs against NP did not. We also investigated the N-linked glycosylation of HTNV GPs and its role in cell fusion. The envelope GPs of HTNV are modified by N-linked glycosylation at five sites: four sites on G1 (N134, N235, N347, and N399) and one site on G2 (N928). Site-directed mutagenesis was used to construct eight GP gene mutants, including five single N-glycosylation site mutants and three double-site mutants, which were then expressed in Vero E6 cells. The oligosaccharide chain on residue N928 of G2 was found to be crucial for cell fusion after exposure to a low pH. These results suggest that G2 is likely to be the fusion protein of HTNV. |
Download PDF |
JM45(1)-08.pdf |