Rab5与Rab7调控N2a细胞内狂犬病病毒的早期感染

Rab5and Rab7regulate the early infection of rabies virus in n2a cells

狂犬病病毒(rabies virus,RABV)作为一种高度嗜神经性的病毒,通过网格蛋白介导和pH依赖的内吞途径侵入神经细胞,然后经胞内体途径进行传输。已有研究表明,Rab5和Rab7是介导胞内体分选、成熟及定向运输的关键蛋白,而RABV胞内运输是否也受到这两者的调控尚不清楚。本试验通过免疫荧光、Western blot及TCID50等技术,检测了N2a中RABV核蛋白(N)和Rab5与Rab7的胞内共定位及RNAi下调Rab5与Rab7表达时,N蛋白表达水平、病毒滴度等的变化。结果发现,Rab5和Rab7与RABV N蛋白存在共定位;当Rab5和Rab7表达下调,RABV感染初期N蛋白表达显著下降,且病毒TCID50也随之降低。结果表明,RABV感染受Rab5和Rab7调节。为进一步解析狂犬病病毒逆轴浆传输机制提供了新的数据。

Rabies virus（RABV）is a highly neurotropic virus that follows clathrin-mediated endocytosis and pH dependent pathway for the trafficking and invasion in the neuronal cells.Rab5 and Rab7play critical roles in endosomal sorting,maturity and targeting for molecular cargoes.However,their precise function in the early stage of RABV infection remains elusive.Immunofluorescence,Western-blot,and TCID50 titration were carried out to determine the co-localization of nucleoprotein（N）with either Rab5 or Rab7and,N protein and RABV titers under down-regulation of Rab5 and Rab7expression.The results showed that N protein could co-localize with both Rab5 and Rab7in the cytoplasm of N2 acells,while.N protein and RABV titers were significantly decreased in the early infection when Rab5 or Rab7knocked-down.These data suggested that early infection of RABV strongly correlates with expression of Rab5 and Rab7,which in turn indicates some helpful clues to explain the retrograde transport mechanism of RABV infection.