The ORF7b Protein of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) Is Expressed in Virus-Infected Cells and Incorporated into SARS-CoV Particles

Scott R. Schaecher; Jason M. Mackenzie; Andrew Pekosz

doi:10.1128/JVI.01691-06

FIG. 4.

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The ORF7b protein does not form disulfide-linked oligomers. 293T cells were transfected with either control plasmid (mock) or plasmids expressing the cDNAs for the influenza A virus M2 protein (A) or SARS-CoV ORF7b (B). The cells were lysed 18 h posttransfection, separated by SDS-PAGE under reducing (+DTT) or nonreducing (−DTT) conditions, and analyzed for protein expression by Western blotting. The M2 protein formed characteristic disulfide-linked dimers (d) and tetramers (t) under nonreducing conditions and monomers (m) in reducing conditions.