Abstract
The Cydia pomonella granulovirus (CpGV) GP37 has synergistic effects on the infectivity of nucleopolyhedroviruses (NPVs), however, the mechanism employed is unclear. In this study, in vitro and in vivo binding assays indicated that GP37 efficiently bound to the midgut peritrophic membrane (PM) of Spodoptera exigua larvae. Treatment with GP37 led to the damage of the PM’s compacted structure and the generation of the PM perforations, and the enhancement of the PM’s permeability. qPCR results further demonstrated that GP37 increased the ability of occlusion-derived virions (ODV) to cross the PM. R18-labeling experiments exhibited that GP37 also promoted the fusion of ODVs and insect midgut epithelia. Altogether, our present results revealed that the synergistic mechanism of GP37 to the infectivity of NPV might involve two parts. GP37 damaged the integrity of the PM after binding, which enhanced the PM’s permeability and increased the ability of ODVs to cross the PM, finally facilitating the ODVs reaching the midgut. In addition, GP37 promoted the fusion of ODVs and insect midgut epithelia. Our data expand the understanding of the mechanism used by baculovirus synergistic factors and provide a foundation for the development of high-efficiency baculoviral insecticides.
Highlights
Baculoviridae are pathogenic for insects and have large double-stranded DNA genomes of 80–180 kb [1] and produce two forms of virions; an occluded form that is present in the occlusion bodies, and a budded form that spreads the infection within the insect [2]
1, 21,and incubated with and 6 h; lane 4, Cydia pomonella granulovirus (CpGV) GP37 expressed in cell free system; lane 5, peritrophic membrane (PM) incubated with distilled water 6 h
CpGV GP37 expressed in cell free system; lane 4, PM of healthy S. exigua larvae fed with artificial dietdiet. (B): M, protein marker; lane 1, bovine serum albumin (BSA); lane 2 and 3, PM of S. exigua larvae after feeding BSA for
Summary
Baculoviridae are pathogenic for insects and have large double-stranded DNA genomes of 80–180 kb [1] and produce two forms of virions; an occluded form that is present in the occlusion bodies, and a budded form that spreads the infection within the insect [2]. GP37s and fusolins contain a spindle-shaped occlusion bodies and, GP37 is present in occlusion bodies and predicted chitin-binding domain [4,5,6]. It has been reported that entomopoxvirus fusolin plays a role in the enhancement of occlusion-derived virions (ODV) and budded viruses [11]. Entomopoxvirus fusolin plays a role thePM enhancement of entomopoxvirus entomopoxvirus spindles indicated that they contained a globular domain that is related to lytic infection [12,13] by causing disruption of the PM [14]. Are dissolved, and thethat monooxygenase domain exposed can digest the of chitinovorous It is thought upon ingestion by theis host, the and spindles are dissolved, chitin-rich. Causing in disruption of the PM and facilitating the viral infection are described
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
