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[Display omitted] • Sequenced mitogenomes of the species Phellinotus piptadeniae and Trametes villosa. • Variation in mtDNA size is due to non-coding regions, introns, HEGs, and uORFs. • Possible existence of horizontal gene transfer events mediated by the activity of HEGs. • GC content may be used to distinguish coding from non-coding sequences. • Mitochondrial genes in the nuclear genome are not common in Agaricomycetes. The mitochondrion is an organelle found in eukaryote organisms, and it is vital for different cellular pathways. The mitochondrion has its own DNA molecule and, because its genetic content is relatively conserved, despite the variation of size and structure, mitogenome sequences have been widely used as a promising molecular biomarker for taxonomy and evolution in fungi. In this study, the mitogenomes of two fungal species of Agaricomycetes class, Phellinotus piptadeniae and Trametes villosa , were assembled and annotated for the first time. We used these newly sequenced mitogenomes for comparative analyses with other 55 mitogenomes of Agaricomycetes available in public databases. Mitochondrial DNA (mtDNA) size and content are highly variable and non-coding and intronic regions, homing endonucleases (HEGs), and unidentified ORFs (uORFs) significantly contribute to the total size of the mitogenome. Furthermore, accessory genes (most of them as HEGs) are shared between distantly related species, most likely as a consequence of horizontal gene transfer events. Conversely, uORFs are only shared between taxonomically related species, most probably as a result of vertical evolutionary inheritance. Additionally, codon usage varies among mitogenomes and the GC content of mitochondrial features may be used to distinguish coding from non-coding sequences. Our results also indicated that transposition events of mitochondrial genes to the nuclear genome are not common. Despite the variation of size and content of the mitogenomes, mitochondrial genes seemed to be reliable molecular markers in our time-divergence analysis, even though the nucleotide substitution rates of mitochondrial and nuclear genomes of fungi are quite different. We also showed that many events of mitochondrial gene shuffling probably happened amongst the Agaricomycetes during evolution, which created differences in the gene order among species, even those of the same genus. Altogether, our study revealed new information regarding evolutionary dynamics in Agaricomycetes. [ABSTRACT FROM AUTHOR]

In this report, we described the genome of a novel baculovirus isolated fromthemonocot insect pestMocis latipes, the striped grass looper. The genome has 134,272 bp in length with a G + C content of 38.3%. Based on the concatenated sequence of the 38 baculovirus core genes, we found that the virus is a betabaculovirus closely related to the noctuid-infecting betabaculoviruses including Pseudaletia unipuncta granulovirus (PsunGV), Trichoplusia ni granulovirus (TnGV), Helicoverpa armigera granulovirus (HearGV), and Xestia c-nigrum granulovirus (XecnGV). The virus may constitute a new Betabaculovirus species tentatively named Mocis latipes granulovirus (MolaGV). After gene content analysis, five open reading frames (ORFs) were found to be unique to MolaGV and several auxiliary genes were found including iap-3, iap-5, bro-a, bro-b, and three enhancins. The virus genome lacked both chitinase and cathepsin. We then looked at the evolutionary history of the enhancin gene and found that betabaculovirus acquired this gene from an alphabaculovirus followed by several duplication events. Gene duplication also happened to an endonuclease-like gene. Genomic and gene content analyses revealed both a strict collinearity and gene expansion into the genome of the MolaGV-related species. We also characterized the granulin gene using a recombinant Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and found that occlusion bodies were produced into the nucleus of infected cells and presented a polyhedral shape and no occluded virions within. Overall, betabaculovirus genome sequencing is of importance to the field as few genomes are publicly accessible. Mocis latipes is a secondary pest of maize, rice, and wheat crops in Brazil. Certainly, both the discovery and description of novel baculovirusesmay lead to development of greener and safer pesticides in order to counteract and effectively control crop damage-causing insect populations. [ABSTRACT FROM AUTHOR]

Baculoviruses are capable of infecting a wide diversity of insect pests. In the 1990s, the Dione juno nucleopolyhedrovirus (DijuNPV) was isolated from larvae of the major passionfruit defoliator pest Dione juno juno (Nymphalidae) and described at ultrastructural and pathological levels. In this study, the complete genome sequence of DijuNPV was determined and analyzed. The circular genome presents 122,075 bp with a G + C content of 50.9%. DijuNPV is the first alphabaculovirus completely sequenced that was isolated from a nymphalid host and may represent a divergent species. It appeared closely related to Orgyia pseudotsugata multiple nucleopolyhedrovirus (OpMNPV) and other Choristoneura-isolated group I alphabaculoviruses. We annotated 153 open reading frames (ORFs), including a set of 38 core genes, 26 ORFs identified as present in lepidopteran baculoviruses, 17 ORFs unique in baculovirus, and several auxiliary genes (e.g., bro, cathepsin, chitinase, iap-1, iap-2, and thymidylate kinase). The thymidylate kinase (tmk) gene was present fused to a dUTPase (dut) gene in other baculovirus genomes. DijuNPV likely lost the dut portion together with the iap-3 homolog. Overall, the genome sequencing of novel alphabaculoviruses enables a wide understanding of baculovirus evolution. [ABSTRACT FROM AUTHOR]

The Southern armyworm Spodoptera eridania (Lepidoptera: Noctuidae) is native to the American tropics and a polyphagous pest of several crops. Here we characterized a novel alphabaculovirus isolated from S. eridania , isolate Spodoptera eridania nucleopolyhedrivurus CNPSo-165 (SperNPV-CNPSo-165). SperNPV-CNPSo-165 occlusion bodies were found to be polyhedral and to contain virions with multiple nucleocapsids. The virus was lethal to S. eridania and S. albula but not to S. frugiperda. The SperNPV-CNPSo-165 genome was 137.373 bp in size with a G + C content of 42.8%. We annotated 151 ORFs with 16 ORFs unique among baculoviruses. Phylogenetic inference indicated that this virus was closely related to the most recent common ancestor of other Spodoptera -isolated viruses. • We characterized a novel alphabaculovirus of Spodoptera eridania , called SperNPV-CNPSo-165. • SperNPV-CNPSo165 presented polyhedral OBs and multiple-nucleocapsids per ODV. • The virus was able to kill S. eridania and S. albula , but not S. frugiperda. • Its genome is 137,373 bp long with 151 ORFs and may represent a new species. • SperNPV-CNPSo-165 lost a second chondroitinase homolog copy independently. [ABSTRACT FROM AUTHOR]

We described a novel baculovirus isolated from the polyphagous insect pest Rachiplusia nu. The virus presented pyramidal-shaped occlusion bodies (OBs) with singly-embed nucleocapsids and a dose mortality response of 6.9 × 103 OBs/ml to third-instar larvae of R. nu. The virus genome is 128,587 bp long with a G + C content of 37.9% and 134 predicted ORFs. The virus is an alphabaculovirus closely related to Trichoplusia ni single nucleopolyhedrovirus, Chrysodeixis chalcites nucleopolyhedrovirus, and Chrysodeixis includens single nucleopolyhedrovirus and may constitute a new species. Surprisingly, we found co-evolution among the related viruses and their hosts at species level. Besides, auxiliary genes with homologs in other baculoviruses were found, e.g. a CPD-photolyase. The gene seemed to be result of a single event of horizontal transfer from lepidopterans to alphabaculovirus, followed by a transference from alpha to betabaculovirus. The predicted protein appears to be an active enzyme that ensures likely DNA protection from sunlight. • We sequenced a novel baculovirus isolated from the soybean pest Rachiplusia nu. • Rachiplusia nu nucleopolyhedrovirus (RanuNPV) may represent a new tentative species inside genus Alphabaculovirus. • RanuNPV presents pyramidal-shaped occlusion bodies with singly-enveloped nucleocapsides within. • RanuNPV and its closest relatives seemed to coevolve with their host at species level. • The new genome presents a CPD-photolyase class II homolog that retains characteristics of functional enzymes. [ABSTRACT FROM AUTHOR]

Baculoviruses are insect viruses largely used as expression vectors and biopesticides. These viruses can efficiently infect the larval stage of several agricultural pests worldwide causing a lethal disease. In this work, we found a novel baculovirus isolated from the larval stage of Urbanus proteus (L.), the bean leafroller and characterized its complete genome. This is an important pest of several leguminous plants in Brazil and belongs to the butterfly family Hesperiidae, from where no baculovirus genome sequence has been described. This new virus was shown to have the smallest genome among all alphabaculoviruses sequenced to date, with 105,555 bp and 119 putative ORFs. We found ten unique genes, seven bro , and the 38 baculovirus core genes. UrprNPV was found to be related to the Adoxophyes -infecting baculoviruses AdorNPV and AdhoNPV with high genetic distance and a long branch length. Interestingly, few individual core gene-based phylogenies were found to support the relationship of UrprNPV to both AdorNPV and AdhoNPV. Importantly, the increase in number of completely sequenced baculovirus points to a very exciting way to understand baculovirus and its evolution and could potentially help the use of baculovirus as both biopesticides and expression vectors. [ABSTRACT FROM AUTHOR]