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Midgut-specific gene expression by MacoNPV baculovirus during infection of the bertha armyworm, Mamestra configurata

ABSTRACT: Infection of lepidopterans by baculoviruses has been traditionally studied using in vitro systems which enable efficient and highly synchronous infection. Many studies using varied virus-host combinations have yielded great insight into the molecular processes by which these large double-stranded DNA viruses achieve infection of host cells. However, a key difference in the virus strategy for infection between individual hosts, and within an individual host, lies with the production of two different forms of the virus; occlusion derived virus, which enables primary infection of insect gut tissues and budded virus, which efficiently infects a variety of different insect tissues throughout the host. To examine the primary infection of midgut cells specifically, we used MacoNPV infection of Mamestra configurata fourth instar larvae as our model and measured the expression of viral genes over a time course of infection. Both digital PCR and RNA sequencing methods showed the profile of transcription to be different from those typically seen with in vitro methods, having unique collections of genes expressed early, as well as much greater expression of p6.9 and much reduced expression of polh and p10 late, in comparison with in vitro studies. These differences likely reflect unique characteristics of midgut cell infection, and provide clues as to the processes these viruses use to regulate expression of different viral forms used to access different host tissues. Baculoviruses are versatile DNA viruses with great potential both as gene therapy vehicles and as biological control tools. Extensive study of their transcriptome in vitro has yielded valuable tools for use in protein expression systems, however it is critical that we obtain a fuller understanding of their in vivo activities before their full medical and agricultural potential can be realized. In these studies we have assessed the gene expression program from a group II alphabaculovirus in the midgut of its complementary larval host and confirmed that the in vivo activities of baculoviruses are unique from what is known of their in vitro transcriptome. These studies provide a first foray with next-generation molecular tools into the characterization of baculovirus biology in vivo.

ORGANISM(S): Mamestra configurata nucleopolyhedrovirus A

PROVIDER: GSE77147 | GEO | 2016/01/23

SECONDARY ACCESSION(S): PRJNA309548

REPOSITORIES: GEO

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Midgut-specific gene expression by MacoNPV baculovirus during infection of the bertha armyworm, Mamestra configurata

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