MYH9与树突状细胞中TRIF-GEFH1-RhoB信号途径的相关性研究

The Study on the Relationship between MYH9 and TRIF-GEFH1-RhoB Signaling Pathway in Dendritic Cells

为探讨Rho B(ras homolog family member B)靶蛋白MYH9(nonmuscle myosin heavy chain IIa)与TRIF-GEFH1-Rho B信号途径的关系,通过实时定量PCR技术、si RNA干扰技术、激光共聚焦显微镜、流式细胞术以及基因敲除小鼠等,分析了MYH9与TRIF(TIR domain-containing adapter inducing IFNβ)途径、GEFH1(guanine nucleotide-exchange factors H1)以及MHCII(major histocompatibility complex II)的关系。结果显示,在LPS(lipopolysaccharide)刺激后,MYH9的m RNA表达在野生型小鼠的树突状细胞(dendritic cells,DCs)中增加,在TRIF基因敲除小鼠的DCs中则未被上调。在野生型小鼠中MYH9的m RNA上调可被GEFH1的si RNA明显抑制(P<0.01)。同时,在LPS刺激后,MYH9与MHCII在细胞内共定位。MYH9的si RNA还抑制了DCs中LPS介导的MHCII在细胞表面的表达(P<0.05)。这些结果表明,MYH9与TRIF-GEFH1-Rho B信号途径存在相关性。

In order to explore the relationship between the ras homolog family member B（RhoB） targeting protein nonmuscle myosin heavy chain IIa（MYH9） and TRIF-GEFH1-RhoB signal pathway, the relationship between MYH9 and TIR domain-containing adapter inducing IFNβ（TRIF） pathway, guanine nucleotide-exchange factors H1（GEFH1） and major histocompatibility complex II（MHCII） were investigated through Real-time quantitative PCR technique and si RNA interference technique, laser scanning confocal microscopy, flow cytometry and gene knockout mice. The results showed that lipopolysaccharide（LPS） induced the up-regulation of MYH9 mRNA level in DCs from wild-type（WT） mice but not in DCs from TRIF knockout, and si RNA of GEFH1 significantly suppressed the LPS-mediated up-regulation of MYH9 mRNA level（P〈0.01）. After LPS stimulation, MYH9 colocalized with MHCII in DCs. In addition, RNAi of MYH9 inhibited the LPS-mediated surface expression of MHCII in DCs（P〈0.05）. These results indicated that there was a correlation between MYH9 and TRIF-GEFH1-RhoB signaling pathway.