Expression of Spike Protein of SABS Coronaviurs in HeLa Cell
Su Dan, Jin Ying-hua, Xiang Tao (Department of Anatomy, School of Preclinical and forensic Medicine, Sichuan University 610041; Laboratory of Structural Biology, Tsinghua University 100008)
Objective To observe the subcellular orientation of spike protein of SARS-Coronovirus (S protein) while it is transfected by non-virus vector. To illustrate the possible roles that S protein plays during SARS CoV infection. Methods Expression plas-mids containing both S protein and GFP sequence were constructed and transfected into HeLa cell by PolyFect Transfection Reagent. The fusion protein was detected under confo-cal microscope and by Western blotting. Results Fusion protein was located mainly in nucleus and some in cytoplast, but not in cell surface. This orientation did not changed with time course. Western blotting detected a specific band at 80-90 KD. Conclusion S protein was located in nucleus and cytoplasm instead to be assembled into cell membrane while it was transfected in HeLa cell by non-virus vector. It was not located as full length in HeLa cell. Therefore, the protease cut-site in the S protein can not be excluded.