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The availability of next-generation sequencing (NGS) in recent years has facilitated a revolution in the availability of mitochondrial (mt) genome sequences. The mt genome is a powerful tool for comparative studies and resolving the phylogenetic relationships among insect lineages. The mt genomes of phytophagous scarabs of the subfamilies Cetoniinae and Dynastinae were under-represented in GenBank. Previous research found that the subfamily Rutelinae was recovered as a paraphyletic group because the few representatives of the subfamily Dynastinae clustered into Rutelinae, but the subfamily position of Dynastinae was still unclear. In the present study, we sequenced 18 mt genomes from Dynastinae and Cetoniinae using next-generation sequencing (NGS) to re-assess the phylogenetic relationships within Scarabaeidae. All sequenced mt genomes contained 37 sets of genes (13 protein-coding genes, 22 tRNAs, and two ribosomal RNAs), with one long control region, but the gene order was not the same between Cetoniinae and Dynastinae species. All mt genomes of Dynastinae species showed the same gene rearrangement of trnQ-NCR-trnI-trnM, whereas all mt genomes of Cetoniinae species showed the ancestral insect gene order of trnI-trnQ-trnM. Phylogenetic analyses (IQ-tree and MrBayes) were conducted using 13 protein-coding genes based on nucleotide and amino acid datasets. In the ML and BI trees, we recovered the monophyly of Rutelinae, Cetoniinae, Dynastinae, and Sericinae, and the non-monophyly of Melolonthinae. Cetoniinae was shown to be a sister clade to (Dynastinae + Rutelinae).

We determined 15 complete and two nearly complete mitogenomes of Heptageniidae belonging to three subfamilies (Heptageniinae, Rhithrogeninae, and Ecdyonurinae) and six genera (Afronurus, Epeorus, Leucrocuta, Maccaffertium, Stenacron, and Stenonema). Species of Rhithrogeninae and Ecdyonurinae had the same gene rearrangement of CR-I-M-Q-M-ND2, whereas a novel gene rearrangement of CR-I-M-Q-NCR-ND2 was found in Heptageniinae. Non-coding regions (NCRs) of 25–47 bp located between trnA and trnR were observed in all mayflies of Heptageniidae, which may be a synapomorphy for Heptageniidae. Both the BI and ML phylogenetic analyses supported the monophyly of Heptageniidae and its subfamilies (Heptageniinae, Rhithrogeninae, and Ecdyonurinae). The phylogenetic results combined with gene rearrangements and NCR locations confirmed the relationship of the subfamilies as (Heptageniinae + (Rhithrogeninae + Ecdyonurinae)). To assess the effects of low-temperature stress on Heptageniidae species from Ottawa, Canada, we found 27 positive selection sites in eight protein-coding genes (PCGs) using the branch-site model. The selection pressure analyses suggested that mitochondrial PCGs underwent positive selection to meet the energy requirements under low-temperature stress.

Long non-coding regions (NCRs) and gene rearrangements are commonly seen in mitochondrial genomes of Mantodea and are primarily focused on three regions: CR-I-Q-M-ND2, COX2-K-D-ATP8, and ND3-A-R-N-S-E-F-ND5. In this study, eight complete and one nearly complete mitochondrial genomes of praying mantises were acquired for the purpose of discussing mitochondrial gene rearrangements and phylogenetic relationships within Mantodea, primarily in the newly established families Haaniidae and Gonypetidae. Except for Heterochaeta sp. JZ-2017, novel mitochondrial gene arrangements were detected in Cheddikulama straminea, Sinomiopteryx graham, Pseudovates chlorophaea, Spilomantis occipitalis. Of note is the fact that one type of novel arrangement was detected for the first time in the Cyt b-S2-ND1 region. This could be reliably explained by the tandem replication-random loss (TDRL) model. The long NCR between trnT and trnP was generally found in Iridopteryginae and was similar to the ND4L or ND6 gene. Combined with gene rearrangements and intergenic regions, the monophyly of Haaniidae was supported, whereas the paraphyly of Gonypetidae was recovered. Furthermore, several synapomorphies unique to some clades were detected that conserved block sequences between trnI and trnQ and gaps between trnT and trnP in Toxoderidae and Iridopteryginae, respectively.

Objective This study aimed to investigate DNA sequences that are substantially homologous to the corresponding RNA sequence sections of the hepatitis C virus (HCV). These DNA sequences are present in the whole DNA extracted from peripheral blood mononuclear cells (PBMCs) of HCV-negative subjects. We presumed that these experimentally proven 5′-noncoding region (5′-NCR) homologous DNA sequences could be contained in the extrachromosomal circular DNA (eccDNA) fraction as part of the whole cellular DNA. Methods Home-made polymerase chain reaction (PCR) with whole cellular and isolated eccDNA, nucleotide basic local alignment search tool (BLASTn) alignments, and tests for patterns of methylation in selected sequence sections were performed. Results The PCR tests revealed DNA sequences of up to 320 bp that broadly matched the corresponding sequence sections of known HCV genotypes. In contrast, BLASTn alignment searches of published HCV 5′-NCR sequences with human genome databases revealed only sequence segments of up to 36 bp of the 5′-NCR. The composition of these sequences shows missing base pairs, base pair mismatches as well as complete homology with HCV reference sequences. These short sequence sections are present in numerous copies on both the same and different chromosomes. The selected sequence region within the DNA sequences of the 5′-NCR revealed a broad diversity of individual patterns of methylation. Conclusions The experimental results confirm our assumption that parts of the HCV 5′-NCR genomic RNA sequences are present at the DNA level in the eccDNA fraction of PBMCs. The tests for methylation patterns therein revealed individual methylomes which could represent an epigenetic feature. The respective sequence section might be subject to genetic regulation.

There has been several studies worldwide on phylogenetics and genotype distribution of the GB-virus C / Hepatitis G virus (GBV-C/HGV). However, in their great majority, those investigations were based on some epidemiologically linked group, rather than on a representative sampling of the general population. The present is a continuation of the first study in Brazil with such a population; it addresses the GBV-C/HGV phylogenetics and genotype distribution based on samples identified among more than 1,000 individuals of the city of São Paulo. For this purpose, a 728 bp fragment of the 5´non-coding region (5´NCR) of the viral genome, from 24 isolates, was sequenced and subjected to phylogenetic analysis. Genotypes 1, 2a and 2b were found at 8.3% (2/24), 50% (12/24) and 41.7% (10/24), respectively. In conclusion São Paulo displays a genotype distribution similar to the published data for other States and Regions of Brazil, endorsing the notion that types 1 and 2 would have entered the country with African and European people, respectively, since its earliest formation. Há na literatura vários estudos filogenéticos e de distribuição de genótipos do chamado \"Vírus GB-C\" ou da \"Hepatite G\", mais conhecido pela dupla sigla \"GBV-C/HGV\". Ocorre que, em sua grande maioria, estas pesquisas foram realizadas com amostras de grupos ligados epidemiologicamente e não com indivíduos representativos da população geral. O presente estudo é uma continuação do primeiro trabalho no Brasil feito com este tipo de amostragem. Trata-se de análise filogenética e distribuição genotípica do GBV-C/HGV a partir de amostras isoladas dentre mais de 1.000 indivíduos da cidade de São Paulo. Para tanto, um fragmento de 728 pares de base da região 5' não-codificadora (5´NCR) do genoma viral, de 24 amostras, foi sequenciado e submetido à analise filogenética. Foram identificados os genótipos 1, 2a e 2b nas respectivas freqüências: 8,3% (2/24), 50% (12/24) e 41,7% (10/24). Concluindo, São Paulo apresenta uma distribuição de genótipos semelhante à publicada para outros estados e regiões do Brasil, endossando a idéia de que os tipos 1 e 2 teriam vindo com os africanos e europeus, respectivamente, e portanto estariam na população do país desde a sua formação.