Fang Minggang, Nie Yingchao, Harris Stephanie, Erlandson Martin A, Theilmann David A
Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, Summerland, British Columbia,Canada.
J Virol. 2009 Dec;83(23):12569-78. doi: 10.1128/JVI.01141-09. Epub 2009 Sep 16.
Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac96 is a core gene, but its role in virus replication is still unknown. To determine its role in the baculovirus life cycle, we used the AcMNPV bacmid system to generate an ac96-null virus (vAc(96)(null)). Our analyses showed that the absence of ac96 does not affect budded virus (BV) production or viral DNA replication in infected Sf9 cells. Western blotting and confocal immunofluorescence analysis showed that AC96 is expressed in both the cytoplasm and the nucleus throughout infection. In addition, AC96 was detected in the envelope fractions of both BV and occlusion-derived virus. Injection of vAc(96)(null) BV into the hemocoel killed Trichoplusia ni larvae as efficiently as repaired and control viruses; however, vAc(96)(null) was unable to infect the midgut tissue of Trichoplusia ni larvae when inoculated per os. Therefore, the results of this study show that ac96 encodes a new per os infectivity factor (PIF-4).
苜蓿银纹夜蛾多核多角体病毒（AcMNPV）的ac96是一个核心基因，但其在病毒复制中的作用尚不清楚。为了确定其在杆状病毒生命周期中的作用，我们使用AcMNPV杆粒系统构建了一个ac96缺失病毒（vAc(96)(null)）。我们的分析表明，ac96的缺失不影响感染的Sf9细胞中出芽病毒（BV）的产生或病毒DNA复制。蛋白质免疫印迹和共聚焦免疫荧光分析表明，在整个感染过程中，AC96在细胞质和细胞核中均有表达。此外，在BV和多角体衍生病毒的包膜组分中均检测到AC96。将vAc(96)(null) BV注射到血腔中杀死草地贪夜蛾幼虫的效率与修复病毒和对照病毒相同；然而，当经口接种时，vAc(96)(null)无法感染草地贪夜蛾幼虫的中肠组织。因此，本研究结果表明，ac96编码一种新的经口感染因子（PIF-4）。
