Bombyx mori nucleopolyhedrovirus ORF9 is a gene involved in the budded virus production and infectivity.
Bombyx mori nucleopolyhedrovirus ORF9 is a gene involved in the budded virus production and infectivity.
复制标题
DOI：
10.1099/vir.0.004903-0
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Zhang-nv Yang;Hai-Jun Xu;S. Thiem;Yi-Peng Xu;Jun-Qing Ge;Xu-Dong Tang;Cai-Hong Tian;Chuan-Xi Zhang
中科院分区：
文献类型：
--
作者：
Zhang-nv Yang;Hai-Jun Xu;S. Thiem;Yi-Peng Xu;Jun-Qing Ge;Xu-Dong Tang;Cai-Hong Tian;Chuan-Xi Zhang
家蚕核型多角体病毒（BmNPV）的ORF 9（Bm 9）在所有已完全测序的鳞翅目核型多角体病毒中是保守的。RT-PCR分析表明Bm 9是一个早、晚转录基因，在感染后3 h开始转录，免疫荧光显微镜显示Bm 9主要定位于感染细胞的细胞质中。为了确定Bm 9在病毒感染过程中的作用，通过在大肠杆菌中作为杆粒繁殖的BmNPV基因组中重组来敲除Bm 9。与野生型（wt）杆粒相比，Bm 9缺失的杆粒的出芽病毒（BV）产量降低了10倍以上;然而，病毒DNA复制的动力学不受影响。BV生产中的缺陷通过Bm 9拯救杆粒恢复。此外，电子显微镜观察显示，多面体的形成不受Bm 9缺失的影响。生物测定结果表明，Bm 9缺失的杆状病毒对五龄幼虫B的致死时间延长了14-22 h。家蚕幼虫的LD（50）比野生型杆粒高15倍。总之，Bm 9是体内和体外病毒产生和感染性的重要但不是必需的因素。
The ORF9 of Bombyx mori nucleopolyhedrovirus (BmNPV) (Bm9) is conserved in all completely sequenced lepidopteran nucleopolyhedroviruses. RT-PCR analysis demonstrated that Bm9 is an early and late transcribed gene that is initiated at 3 h post-infection, and immunofluorescence microscopy showed that Bm9 is localized mainly in the cytoplasm of infected cells. To determine the role of Bm9 during virus infection, Bm9 was knocked out by recombination in a BmNPV genome propagated as a bacmid in Escherichia coli. The budded virus (BV) production of Bm9-deleted bacmids was reduced more than 10-fold compared with wild-type (wt) bacmid; however, the kinetics of viral DNA replication were unaffected. The defect in BV production was recovered by the Bm9 rescue bacmid. In addition, electron microscope observations revealed that polyhedra formation was not affected by the deletion of Bm9. Bioassays showed that the Bm9-deleted bacmid took approximately 14-22 h longer to kill fifth instar B. mori larvae than wt bacmid, and the LD(50) was about 15 times higher than that of the wt bacmid. In conclusion, Bm9 is an important but not essential factor in virus production and infectivity in vivo and in vitro.