Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
J Virol. 2010 May;84(10):5191-200. doi: 10.1128/JVI.00099-10. Epub 2010 Mar 10.
Lepidopteran baculovirus-specific protein FP25K performs many roles during the infection cycle, including functions in the production of occlusion bodies (OBs) and budded viruses (BVs), oral infection, and postmortem host degradation. To explore the common and specific functions of FP25K proteins among lepidopteran baculoviruses, we performed comparative analyses of FP25K proteins from group I and group II nucleopolyhedroviruses (NPVs) and granulovirus (GV). Using recombinant Bombyx mori NPVs (BmNPVs), we showed that the FP25Ks from NPVs were able to eliminate all the phenotypic defects observed in an infection with a BmNPV mutant lacking functional fp25K but that FP25K from GV did not show abilities to recover oral infectivity and postmortem host degradation. We also observed that introduction of Autographa californica multiple NPV (AcMNPV) fp25K into the BmNPV genome enhanced OB and BV production. According to these results, we generated a novel BmNPV-based expression vector with AcMNPV fp25K and examined its potential in BmN cells and B. mori larvae. Our results showed that the introduction of AcMNPV fp25K significantly increases the expression of foreign gene products in cultured cells and shortens the time for obtaining the secreted recombinant proteins from larval hemolymph.
鳞翅目杆状病毒特异性蛋白 FP25K 在感染周期中发挥多种作用，包括在形成包埋体（OBs）和出芽病毒（BVs）、口服感染和死后宿主降解中的功能。为了探索鳞翅目杆状病毒 FP25K 蛋白之间的共同和特异功能，我们对 I 组和 II 组核多角体病毒（NPVs）和颗粒体病毒（GV）的 FP25K 蛋白进行了比较分析。使用重组家蚕杆状病毒（BmNPV），我们表明，NPV 的 FP25Ks 能够消除 BmNPV 突变体感染中观察到的所有表型缺陷，但 GV 的 FP25K 没有恢复口服感染力和死后宿主降解的能力。我们还观察到，将美洲棉铃虫多角体病毒（AcMNPV）fp25K 引入 BmNPV 基因组增强了 OB 和 BV 的产生。根据这些结果，我们生成了一种带有 AcMNPV fp25K 的新型 BmNPV 表达载体，并在 BmN 细胞和家蚕幼虫中检验了其潜力。我们的结果表明，引入 AcMNPV fp25K 显著增加了培养细胞中外源基因产物的表达，并缩短了从幼虫血淋巴中获得分泌型重组蛋白的时间。
