Characterization of the 3a Protein of SARS-associated Coronavirus in Infected Vero E6 Cells and SARS Patients

Academy of Military Medical Sciences, T’ien-ching-shih, Tianjin Shi, China
Journal of Molecular Biology (Impact Factor: 4.33). 08/2004; 341(1):271-9. DOI: 10.1016/j.jmb.2004.06.016
Source: PubMed


Proteomics was used to identify a protein encoded by ORF 3a in a SARS-associated coronavirus (SARS-CoV). Immuno-blotting revealed that interchain disulfide bonds might be formed between this protein and the spike protein. ELISA indicated that sera from SARS patients have significant positive reactions with synthesized peptides derived from the 3a protein. These results are concordant with that of a spike protein-derived peptide. A tendency exists for co-mutation between the 3a protein and the spike protein of SARS-CoV isolates, suggesting that the function of the 3a protein correlates with the spike protein. Taken together, the 3a protein might be tightly correlated to the spike protein in the SARS-CoV functions. The 3a protein may serve as a new clinical marker or drug target for SARS treatment.

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Available from: Ruifu Yang
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    • "The 3a protein contains three transmembrane domains at the N-terminus and a C-terminal cytoplasmic domain of ~150 amino acids [18]. The cytoplasmic domain contains a tyrosine based sorting motif, YXXΦ (where X can be any residue and Φ is a residue with a bulky hydrophobic side chain) and a di-acidic EXD motif. "
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    • "Further, characterization of the 3a protein of SARS-CoV in infected Vero E6 cells and sera from SARS patients showed that there was a tendency existed for co-mutation between the 3a protein and the spike protein of SARS-CoV isolates. The conclusion was that the 3a protein might be tightly correlated to the spike protein in the SARS-CoV functions and it may serve as a new clinical marker or drug target for SARS treatment (Zeng et al., 2004b). To analyze the differential cellular response to SARS-CoV, the proteome of Vero E6 cells with and without infection of SARS- CoV were resolved and quantitated with two-dimensional gel electrophoresis followed by ESI-MS/MS identification. "
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