Construction and characterization of a novel baculovirus vector based on the White spot syndrome virus immediately-early promoter
基于对虾白斑综合症病毒极早期启动子的新型杆状病毒表达载体的构建与分析

Abstract: Objective] To construct a universal baculovirus vector for efficient gene expression in both invertebrate and vertebrate cell lines. Methods] Using the Bac-To-Bac system, we genetically engineered the immediately-early 1 gene promoter (ie1 promoter) from White spot syndrome virus into a baculovirus vector that was pseudotyped with Vesicular stomatitis virus glycoprotein (VSV G). We placed the enhanced green fluorescent protein (EGFP) gene under the control of ie1 promoter in the baculovirus vector to get the reporter recombinant baculovirus, vAc-G-EGFP. We tested the reporter EGFP gene expression in tested cell lines through virus infection or transduction experiments using direct fluorescence microscopy and Western blot analysis. Results] Under the control of ie1 promoter, vAc-G-EGFP could efficiently express the EGFP reporter gene in both invertebrate and vertebrate cells. The steady-state expression level of EGFP in vertebrate cell lines were different from that in invertebrate Sf9 cells as reflected by Western blot assays. Conclusion] The ie1 promoter-based and VSV G-pseudotyped baculovirus vector presents a unique and effective tool to express target genes simultaneously in various cell systems; the novel baculovirus-mediated gene expression system developed in this study has the potential to be widely used in both basic and applied research.