布鲁氏菌LPS及VirB2缺失株对巨噬细胞SUMO-1表达及Ubc-9转录水平的影响

EFFECTION OF BRUCELLA LPS AND VIRB2-DELETION STRAIN ON EXPRESSION OF SUMO-1 AND TRANSCRIPTION LEVEL OF UBC-9 IN MACROPHAGES

为了初步探究布鲁氏菌众多毒力因子对小鼠巨噬细胞中类泛素SUMO-1和偶联酶Ubc-9表达的影响,本研究使用经提纯的布鲁氏菌16M脂多糖(lipopolysaccharide,LPS)以及布鲁氏菌Ⅳ型分泌系统的VirB2缺失株侵染小鼠巨噬细胞,在不同时间段收集细胞,提取细胞总RNA和细胞总蛋白,通过qRT-PCR和Western blot技术分别检测类泛素SUMO-1的表达水平和偶联酶Ubc-9的mRNA的转录水平。结果表明,不同浓度的布鲁氏菌16M脂多糖LPS侵染小鼠巨噬细胞后,细胞中类泛素SUMO-1的表达水平和偶联酶Ubc-9的mRNA的转录水平均未发生明显变化;布鲁氏菌VirB2缺失株与阴性对照组相比,类泛素SUMO-1的表达水平和偶联酶Ubc-9的mRNA的转录水平在各侵染时间段差异具有显著统计学意义(P<0.05),可初步判定在宿主细胞中,布鲁氏菌Ⅳ型分泌系统会影响类泛素SUMO-1蛋白的表达水平和Ubc-9mRNA的转录水平,从而在胞内稳定繁殖。

The mouse macrophages were administered with purified Brucella 16M lipopolysaccharid(LPS)and VirB2 mutant strain of the Brucella typeⅣsecretion system to investigate the effect of various virulence factors on the expression of ubiquitin SUMO-1 and transcription levels of Ubc-9.The cells were then harvested at different times for extraction of cellular RNA and total protein.The expression level of SUMO-1 was analyzed in Western blot and transcription level of Ubc-9 mRNA was examined in qRT-PCR.As compared with the negative control group,the expression of SUMO-1 and transcription level of Ubc-9 mRNA did not change after the mouse macrophages were treated with different concentrations of Brucella 16M LPS.The expression of SUMO-1 and transcription level of Ubc-9 in the VirB2-mutant group was significantly different(P<0.05).It concluded that Brucella typeⅣsecretion system affected the expression of ubiquitin SUMO-1 and transcription level of Ubc-9 in the host cells,causing steady propagation within the infected cells.