AcMNPV肌动蛋白核定位基因的亚细胞定位

Localization of AcMNPV NLA Genes in Sf9 Cells

当前细胞核内肌动蛋白的功能是一个研究热点,核内存在肌动蛋白并参与细胞核内发生的许多生命活动。杆状病毒是迄今唯一报道的利用核内肌动蛋白进行复制增殖的病原微生物,为核内肌动蛋白的结构与功能的研究提供了独特的系统。有报道显示AcMNPV的ie-1,pe38,ac4,he65,ac102和ac152基因与肌动蛋白单体的核转运有关,然而关于这六个基因的亚细胞定位及其在肌动蛋白入核过程中的功能并没有深入的研究。本文首次揭示了这六个基因的亚细胞定位,IE1和AC152是全细胞分布,PE38和AC102也为核质分布,但主要分布在细胞核中,而AC4和HE65定位于细胞质。但AC102和IE1可以分别介导AC4和HE65入核。同时我们发现当使用外源强启动子OpIE2,在转染ie-1或pe38之后表达ac4和he65可以部分招募肌动蛋白单体入核,而时序性共转染这四个基因则可招募最多肌动蛋白单体入核。对肌动蛋白核定位基因在细胞中的定位分析为进一步了解杆状病毒介导肌动蛋白入核的分子机理提供支持。

Nuclear actin which plays a key role in many nucleic processes has become a research hotspot.Baculovirus is the only reported pathogen using nuclear actin to replicate and proliferate.However,little is known about the mechanism of monomeric G-actin accumulation within nuclei of baculovirus-infected cells.It has been reported that AcMNPV ie-1,pe38,ac4,he65,ac102,and ac152 could be required for mediating nuclear localization of G-actin from transiently transfected results in TN-368 cells.In this paper,we found that IE1,AC152,PE38,AC102 localized in the whole cell and PE38,AC102 localized in the nuclear mainly,while both AC4 and HE65 localized in cytoplasm and could be mediated into the nucleus by AC102 and IE1 respectively for the first time.And ie-1 or pe38,ac4,he65 could mediate nuclear G-actin to accumulate partly,while these four genes were sufficient for recruiting G-actin accumulation within the nucleus when driven by promoter OpIE2.Determining the functions of each of these AcMNPV NLA gene products will advance our understanding of baculovirus biology and function of nuclear actin.