当前位置： SCI文献检索 > VIROLOGY期刊下所有文献 > Genetic analysis of the SARS-coronavirus spike glycoprotein functional domains involved in cell-surface expression and cell-to-cell fusion.

Genetic analysis of the SARS-coronavirus spike glycoprotein functional domains involved in cell-surface expression and cell-to-cell fusion.

Abstract：

:The SARS-coronavirus (SARS-CoV) is the etiological agent of severe acute respiratory syndrome (SARS). The SARS-CoV spike (S) glycoprotein mediates membrane fusion events during virus entry and virus-induced cell-to-cell fusion. To delineate functional domains of the SARS-CoV S glycoprotein, single point mutations, cluster-to-lysine and cluster-to-alanine mutations, as well as carboxyl-terminal truncations were investigated in transient expression experiments. Mutagenesis of either the coiled-coil domain of the S glycoprotein amino terminal heptad repeat, the predicted fusion peptide, or an adjacent but distinct region, severely compromised S-mediated cell-to-cell fusion, while intracellular transport and cell-surface expression were not adversely affected. Surprisingly, a carboxyl-terminal truncation of 17 amino acids substantially increased S glycoprotein-mediated cell-to-cell fusion suggesting that the terminal 17 amino acids regulated the S fusogenic properties. In contrast, truncation of 26 or 39 amino acids eliminating either one or both of the two endodomain cysteine-rich motifs, respectively, inhibited cell fusion in comparison to the wild-type S. The 17 and 26 amino-acid deletions did not adversely affect S cell-surface expression, while the 39 amino-acid truncation inhibited S cell-surface expression suggesting that the membrane proximal cysteine-rich motif plays an essential role in S cell-surface expression. Mutagenesis of the acidic amino-acid cluster in the carboxyl terminus of the S glycoprotein as well as modification of a predicted phosphorylation site within the acidic cluster revealed that this amino-acid motif may play a functional role in the retention of S at cell surfaces. This genetic analysis reveals that the SARS-CoV S glycoprotein contains extracellular domains that regulate cell fusion as well as distinct endodomains that function in intracellular transport, cell-surface expression, and cell fusion.

journal_name

Virology

journal_title

Virology

authors

Petit CM,Melancon JM,Chouljenko VN,Colgrove R,Farzan M,Knipe DM,Kousoulas KG

doi

10.1016/j.virol.2005.06.046

subject

Has Abstract

pub_date

2005-10-25 00:00:00

pages

215-30

issue

eissn

0042-6822

issn

1096-0341

pii

S0042-6822(05)00384-3

journal_volume

341

pub_type

杂志文章

在线工具

Genetic analysis of the SARS-coronavirus spike glycoprotein functional domains involved in cell-surface expression and cell-to-cell fusion.