口蹄疫病毒VP1蛋白介导宿主核糖体蛋白SA调控MAPK信号通路的分子机制

FMDV VP1 protein is multifunctional protein that contains receptor recognition sites and antigenic sites, and can inhibits host innate immune. However, the molecular mechanisms underlying these functions are still unclear. Our previous studyindicate that interactions of host Ribosomal Protein SA (RPSA) and VP1 were confirmed with YTHS and Co-IP methods. Further studies showed over-expression of RPSA can inhibit the replication of FMDV in host cells and it has been proved that PRSA can iinhibit the phosphorylation of key adaptor molecular in MAPK signaling pathway. To illuminate the molecular mechanisms of VP1regulates MAPK signaling pathway via host RPSA, the following studies will be performed: interaction sites between VP1 and RPSA will be identified by Co-IP; eukaryotic expression plasmids and RNA interference plasmids of RPSA will be constructed to detect the changes of transcription, phosphorylation and ubiquitin of node proteins in MAPK and it’s downstream effective molecules which induced by RPSA; VP1 acting sites mutant FMDV strain will be rescued by reverse genetics technique the biological characteristics will tested and compared and then variations of MAPK caused by mutant FMDV will be evaluated. This project entry from the interactions of VP1 and host proteins, uncover MAPK signal transduction regulated via VP1 and RPSA encoded by FMDV, it will lay the foundation to reveal the molecular mechanisms of FMDV replication.

口蹄疫病毒（FMDV）VP1是多功能蛋白，是诱导体液免疫的主要抗原，含有受体识别位点，具有抑制宿主天然免疫的功能，这些功能背后的分子机制仍不清楚。本项目前期通过酵母双杂交（YTHS）和Co-IP鉴定了宿主RPSA和VP1相互作用，且RPSA能够抑制FMDV复制,研究发现RPSA能影响MAPK通路关键节点蛋白的磷酸化水平。为阐明VP1蛋白介导宿主RPSA调控MAPK信号通路的分子机制，本研究利用Co-IP鉴定VP1和RPSA作用位点；构建RPSA真核表达质粒和RNA干扰质粒检测RPSA的变化对MAPK通路节点蛋白转录、磷酸化和泛素化的影响，检测被影响的节点蛋白下游效应分子变化；拯救VP1作用位点突变的毒株，证实该位点对病毒生物学特性的影响，评价该病毒对MAPK通路的影响。该研究从病毒与宿主蛋白互作切入，阐明病毒介导宿主对MAPK信号转导的调控，为揭示FMDV与宿主互作的分子机制奠定基础。

口蹄疫病毒（FMDV）VP1是多功能蛋白，是诱导体液免疫的主要抗原，含有受体识别位点，具有抑制宿主天然免疫的功能，这些功能背后的分子机制仍不清楚。本研究首先验证了VP1和宿主RSPA互作且RPSA抑制了FMDV的复制，在此基础了明确PRSA不影响FMDV入侵宿主细胞，FMDV感染激活的MAPK信号通路有利于FMDV的复制，PRSA抑制了MAPK信号通路进而抑制了FMDV的复制，VP1 37-188和VP1 115-214区段通过和RPSA互作抑制了RPSA对MAPK信号通路的抑制作用从而促进了FMDV的复制。本研究从病毒与宿主蛋白互作切入，阐明病毒蛋白介导宿主蛋白对MAPK信号转导的调控，为揭示FMDV与宿主互作的分子机制奠定基础。