The genome sequence of Pseudoplusia includens single nucleopolyhedrovirus and an analysis of p26 gene evolution in the baculoviruses

Abstract

BackgroundPseudoplusia includens single nucleopolyhedrovirus (PsinSNPV-IE) is a baculovirus recently identified in our laboratory, with high pathogenicity to the soybean looper, Chrysodeixis includens (Lepidoptera: Noctuidae) (Walker, 1858). In Brazil, the C. includens caterpillar is an emerging pest and has caused significant losses in soybean and cotton crops. The PsinSNPV genome was determined and the phylogeny of the p26 gene within the family Baculoviridae was investigated.ResultsThe complete genome of PsinSNPV was sequenced (Roche 454 GS FLX – Titanium platform), annotated and compared with other Alphabaculoviruses, displaying a genome apparently different from other baculoviruses so far sequenced. The circular double-stranded DNA genome is 139,132 bp in length, with a GC content of 39.3 % and contains 141 open reading frames (ORFs). PsinSNPV possesses the 37 conserved baculovirus core genes, 102 genes found in other baculoviruses and 2 unique ORFs. Two baculovirus repeat ORFs (bro) homologs, bro-a (Psin33) and bro-b (Psin69), were identified and compared with Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV) and Trichoplusia ni single nucleopolyhedrovirus (TnSNPV) bro genes and showed high similarity, suggesting that these genes may be derived from an ancestor common to these viruses. The homologous repeats (hrs) are absent from the PsinSNPV genome, which is also the case in ChchNPV and TnSNPV. Two p26 gene homologs (p26a and p26b) were found in the PsinSNPV genome. P26 is thought to be required for optimal virion occlusion in the occlusion bodies (OBs), but its function is not well characterized. The P26 phylogenetic tree suggests that this gene was obtained from three independent acquisition events within the Baculoviridae family. The presence of a signal peptide only in the PsinSNPV p26a/ORF-20 homolog indicates distinct function between the two P26 proteins.ConclusionsPsinSNPV has a genomic sequence apparently different from other baculoviruses sequenced so far. The complete genome sequence of PsinSNPV will provide a valuable resource, contributing to studies on its molecular biology and functional genomics, and will promote the development of this virus as an effective bioinsecticide.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-1323-9) contains supplementary material, which is available to authorized users.

Complete Genome Sequences of Six Chrysodeixis includens Nucleopolyhedrovirus Isolates from Brazil and Guatemala

“…The isolates showed high nucleotide sequence identity with both ChinNPV-IC and ChinNPV-ID sharing 96.4% identity and ChinNPV-IF and ChinNPV-IG sharing 99.4% identity with the PsinSNPV-IE genome (7) (GenBank: KJ631622), representative isolate of the species.…”

Comparative Analysis of HaSNPV-AC53 and Derived Strains

“…Baculovirus species have been described using restriction endonuclease digestion profile and Sanger sequencing, and more recently by Next Generation Sequencing (NGS) [10,11,16,17,23,26,27,28,29]. Previous research has shown that HaSNPV and HzSNPV share sequence similarity of up to 99.9%, but could be distinguished by a small number of nucleotide substitutions and by open reading frame (ORF) insertions and deletions in the published consensus genome [17,30,31].…”

Complete Genome Sequences of Seven New Chrysodeixis includens Nucleopolyhedrovirus Isolates from Minas Gerais and Mato Grosso States in Brazil

“…of the family Baculoviridae that has Pseudoplusia includens single nucleopolyhedrovirus-IE (PsinNPV-IE; GenBank accession number KJ631622) as its representative isolate (1,2). We report here the complete genome sequences of seven new isolates of this species, originally obtained from infected Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae) larvae collected on soybeans and cotton in the states of Minas Gerais and Mato Grosso, Brazil.…”