The pangenome of the Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV)

• Grant number: 15/24764-5
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: March 01, 2016
• End date: August 31, 2016
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Paolo Marinho de Andrade Zanotto
• Grantee: Paolo Marinho de Andrade Zanotto
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The alphabaculovirus Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) is the world's most successful viral bioinsecticide. Through the 1980's and 1990's, this virus was extensively used for biological control of populations of Anticarsia gemmatalis (Velvetbean caterpillar) in soybean crops. During this period, genetic studies identified several variable loci in the AgMNPV, however, most of them were not characterized at the sequence level. In this study we report a full genome comparison among 17 wild-type isolates of AgMNPV. We found the pangenome of this virus to contain at least 167 hypothetical genes, 151 of which are shared by all genomes. The gene bro-a that might be involved in host specificity and carrying transporter, is absent in some genomes, and new hypothetical genes were observed. Among these genes there is a unique rnf12-like gene, probably implicated in ubiquitination. Events of gene fission and fusion are common, since four genes have been observed as single or split ORFs. Gain/loss of genomic fragments (from 20 to 900 bp) are observed within tandem repeats, such as in eight direct repeats (drs) and four homologous regions (hrs). Most AgMNPV genes present low nucleotide diversity, and variable genes are mainly located in a locus known to evolve via homologous recombination. The evolution of AgMNPV is mainly driven by small indels, substitutions, gain and loss of nucleotide stretches or entire coding sequences. These variations may cause relevant phenotypic alterations, which probably affect the infectivity of AgMNPV. This work provides novel information on genomic evolution of the AgMNPV in particular and of baculoviruses in general. (AU)