Acquistion of Secreted Proteins from Japanese Encephalitis VI Rus-Infected Cells

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus, a member of the family Flaviviridae, and causes serious viral encephalitis in humans. It is well known that upon viral infection host cell protein expression is induced leading to the production of cytoplasmic proteins and secretory inflammatory cytokines. There is growing evidence that virus particles associate and/or contain host proteins. These proteins may provide viruses with means to escape host immune defense or with mechanism for its release as well as cell entry. Until now, no global profile of secreted proteins in the cultured medium of JEV-infected cells has been measured. To this end, we characterize the effects of JEV infection on the profile of protein secretion of BHK-21 cells by developing a serum-free culture method in combination with LC-MS/MS. As the preliminary results were shown, five secreted proteins, including the molecular chaperones Hsp90, Hsp70, and GRP78, have been identified in the cultured medium from JEV-infected BHK-21 cells. The functional role of GRP78 in the JEV life cycle was further investigated as playing role in facilitating the JE virus infectivity. In this proposal, we will further characterize the global profile of secreted proteins from JEV-infected BHK-21 cells according to our established proteomic approaches; and dissect the functional role(s) of JEV-induced secreted molecular chaperones involving in the JEV life cycle. Finally, the possible mechanism of secretion of JE virus particle depends on co-assembly of molecular chaperones will be illustrated by the end of this project. Overall, the identification and functional analysis of secreted proteins from JEV-infected cells may reveal a role for host cell proteins in JEV pathogenesis.

Project ID:PC10108-0896
External Project ID:NSC101-2320-B182-032