过表达沙门氏菌效应蛋白SopB对HeLa细胞骨架的影响

Role of Salmonella Effector SopB Overexpression on the Cytoskeleton of HeLa Cells

[目的]研究沙门氏菌感染宿州细胞过程中,沙门氏菌Ⅲ型分泌系统的效应蛋白SopB对宿主细胞细胞骨架的影响,同时寻找SopB蛋白调控细胞骨架变化的相关结构域。[方法]利用基因克隆的方法分别构建含鼠伤寒沙门氏菌LT2效应蛋白SopB的全长基因、SopBN末端基因片段及SopB肌醇磷脂酶活性中心氨基酸C460突变体的重组质粒,使其均在HeLa细胞中过量表达,对表达结果进行检测。[结果]SopB重组质粒在HeLa细胞中均能正常表达,其中SopB蛋白的过表达能显著改变HeLa细胞的细胞骨架,使细胞由正常的细胞形态转变为圆形。[结论]通过比较SopB各基因片段对细胞形态的影响,发现SopB过表达在改变HeLa细胞骨架方面与其N末端第46～112位氨基酸残基间的肽断直接相关,而与其肌醇磷脂酶活性关系不大。

[Objective] The paper was to study the role of Salmonella effector SopB to the regulation of cytoskeleton in HeLa cells during Salmonella infection and uncover its function-related domain underlying this function.[Method] The recombinant plasmids were constructed by gene cloning method with Salmonella typhimurium LT2 effector protein SopB gene,SopB N end gene fragment and amino acid C460 mutant of phosphoinositide phosphatase activity center of SopB respectively,which were overexpressed in HeLa cells,were used to detect the expression results.[Result]The recombinant plasmids of SopB could be expressed in HeLa cells normally.The overexpression of SopB could significantly alter the cytoskeleton of HeLa cells,and the cells changed from normal cell shape to round.[Conclusion] In comparison to the effects of those of the SopB truncations,it found that the role of SopB to change of cytoskeleton in the HeLa cells was related to the peptide spaning 46 to 112 amino acids,but uncorrelated to the activity of phosphoinositide phosphatase.