T-rich Region Research Articles

The complete mitochondrial genome of Parotis chlorochroalis (Hampson, 1912) (Lepidoptera: Crambidae)

The complete mitochondrial genome of the Parotis chlorochroalis was sequenced, revaeling a length of 15239 bp with 37 genes and an A + T-rich region. All c13 PCGs begin with typical ATN codons, except COI gene, which starts with CGA. Eleven genes terminate with TAA, two with T–. All 22 tRNA genes exhibit typical cloverleaf structure except for trnS1 P. chlorochroalis has two relatively conserved intergenic regions and two relatively conserved overlapping regions. Phylogenetic analysis support P. chlorochroalis belongs to subfamily Spilomelinae, the topologies of Crambidae are highly congruent with previous studies. This newly sequences mitochondrial genome provides valuable resources for taxonomic inference and evolutionary studies of genus Parotis.

Characterization of the Complete Mitochondrial Genome of Salassa thespis (Lepidoptera: Saturniidae) and Comparison with Other Lepidoptera Species

There are many species of Lepidoptera, but few complete mitochondrial genomes of Lepidoptera have been included in databases. Here, the complete mitochondrial genome sequence of Salassa thespis was isolated and characterized. It was 15,302 bp in length and contained 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and an A + T-rich region. Among the 13 PCGs, the initiation codon of cytochrome c oxidase subunit 1 (cox1) was CGA, and the rest were ATN. The cox1 and cox2 genes had an incomplete stop codon T, while the rest terminated with TAA. Codon usage analysis showed that Phe, Ile, Leu and Asn were the most frequent amino acids, while Trp was the least. Like other Lepidopterans, some conserved motifs were found in the A + T-rich region, including a 17 bp poly-T guided by ATAGA, the AT-rich area and a poly-A element. Bayesian inference and maximum likelihood phylogenetic tree analysis based on 13 PCGs of S. thespis confirmed that it belonged to the Saturniidae family and showed the following relationship: (S. thespis + (Rhodinia fugax + Samia canningi)). The enrichment of mitochondrial DNA provides reference information for the study of the evolution and diversity of Lepidoptera insects.

Mitogenomic Analysis and Phylogenetic Implications for the Deltocephaline Tribe Chiasmini (Hemiptera: Cicadellidae: Deltocephalinae).

The grassland leafhopper tribe Chiasmini (Cicadellidae: Deltocephalinae) presently comprises 324 described species worldwide, with the highest species diversity occurring in the Nearctic region but a greater diversity of genera occurring in the Old World. In China, this tribe comprises 39 described species in 11 genera, but the fauna remains understudied. The complete mitogenomes of three species of this tribe have been sequenced previously. In order to better understand the phylogenetic position of Chiasmini within the subfamily Deltocephalinae and to investigate relationships among Chiasmini genera and species, we sequenced and analyzed the complete mitogenomes of 13 species belonging to seven genera from China. Comparison of the newly sequenced mitogenomes reveals a closed circular double-stranded structure containing 37 genes with a total length of 14,805 to 16,269 bp and a variable number of non-coding A + T-rich regions. The gene size, gene order, gene arrangement, base composition, codon usage, and secondary structure of tRNAs of the newly sequenced mitogenomes of these 13 species are highly conserved in Chiasmini. The ATN codon is commonly used as the start codon in protein-coding genes (PCGs), except for ND5 in Doratura sp. and ATP6 in Nephotettix nigropictus, which use the rare GTG start codon. Most protein-coding genes have TAA or TAG as the stop codon, but some genes have an incomplete T stop codon. Except for the tRNA for serine (trnS1(AGN)), the secondary structure of the other 21 tRNAs is a typical cloverleaf structure. In addition to the primary type of G-U mismatch, five other types of tRNA mismatches were observed: A-A, A-C, A-G, U-C, and U-U. Chiasmini mitochondrial genomes exhibit gene overlaps with three relatively stable regions: the overlapping sequence between trnW and trnC is AAGTCTTA, the overlapping sequence between ATP8 and ATP6 is generally ATGATTA, and the overlapping sequence between ND4 and ND4L is generally TTATCAT. The largest non-coding region is the control region, which exhibits significant length and compositional variation among species. Some Chiasmini have tandem repeat structures within their control regions. Unlike some other deltocephaline leafhoppers, the sequenced Chiasmini lack mitochondrial gene rearrangements. Phylogenetic analyses of different combinations of protein-coding and ribosomal genes using maximum likelihood and Bayesian methods under different models, using either amino acid or nucleotide sequences, are generally consistent and also agree with results of prior analyses of nuclear and partial mitochondrial gene sequence data, indicating that complete mitochondrial genomes are phylogenetically informative at different levels of divergence within Chiasmini and among leafhoppers in general. Apart from Athysanini and Opsiini, most of the deltocephaline tribes are recovered as monophyletic. The results of ML and BI analyses show that Chiasmini is a monophyletic group with seven monophyletic genera arranged as follows: ((Zahniserius + (Gurawa + (Doratura + Aconurella))) + (Leofa + (Exitianus + Nephotettix))).

The Complete Mitochondrial Genome of Chilo infuscatellus (Lepidoptera: Pyralidae), and Related Phylogenetic Analysis.

The Chilo infuscatellus (Lepidoptera: Pyralidae) is a significant pest of sugarcane in China. The genome-level characteristics of this pest are important genetic resources for identification, phylogenetic analysis, and even management. In the present study, the complete mitogenome of C. infuscatellus was sequenced and characterized. The assembled mitochondrial genome is 15,252bp in length and includes 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and an A + T-rich region. Except for the CGA codon for the cox1 gene, the PCGs are initiated with ATN codons (ATG, ATT, and ATA). These PCGs are terminated with TAA or an incomplete termination codon of a single T. Except for the loss of the "DHU" arm for trnS1, the tRNA genes were folded into the typical cloverleaf structure. The A + T-rich region has a high AT content of 96.19% and contains the motifs "ATAGA" and "ATTTA", as well as a 19bp poly-T stretch and microsatellite regions. The C. infuscatellus mitogenome exhibits a conserved gene order among lepidopteran insects, with a rearrangement of the trnM gene compared to the ancestral insect gene order. Phylogenetic analysis based on the 13 PCGs using Bayesian inference (BI) and maximum likelihood (ML) methods confirmed the monophyly of Pyralidae and Crambidae within Pyraloidea. The relationships between subfamilies in Pyralidae can be described as (Galleriinae + (Phycitinae + (Pyralinae + Epipaschiinae))). The "PS clade" and "non-PS clade" were formed within the family Crambidae. These findings provide valuable genetic resources for the identification, phylogenetic analysis, and management of sugarcane borers, contributing significantly to our understanding of the phylogeny of Pyraloidea insects and their evolution.

The First Two Complete Mitochondrial Genomes for the Subfamily Meligethinae (Coleoptera: Nitidulidae) and Implications for the Higher Phylogeny of Nitidulidae.

The phylogenetic status of the family Nitidulidae and its sister group relationship remain controversial. Also, the status of the subfamily Meligethinae is not fully understood, and previous studies have been mainly based on morphology, molecular fragments, and biological habits, rather than the analysis of the complete mitochondrial genome. Up to now, there has been no complete mitochondrial genome report of Meligethinae. In this study, the complete mitochondrial genomes of Meligethinus tschungseni and Brassicogethes affinis (both from China) were provided, and they were compared with the existing complete mitochondrial genomes of Nitidulidae. The phylogenetic analysis among 20 species of Coleoptera was reconstructed via PhyloBayes analysis and Maximum likelihood (ML) analysis, respectively. The results showed that the full lengths of Meligethinus tschungseni and Brassicogethes affinis were 15,783 bp and 16,622 bp, and the AT contents were 77% and 76.7%, respectively. Each complete mitochondrial genome contains 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and a control region (A + T-rich region). All the PCGs begin with the standard start codon ATN (ATA, ATT, ATG, ATC). All the PCGs terminate with a complete terminal codon, TAA or TAG, except cox1, cox2, nad4, and nad5, which terminate with a single T. Furthermore, all the tRNAs have a typical clover-leaf secondary structure except trnS1, whose DHU arm is missing in both species. The two newly sequenced species have different numbers and lengths of tandem repeat regions in their control regions. Based on the genetic distance and Ka/Ks analysis, nad6 showed a higher variability and faster evolutionary rate. Based on the available complete mitochondrial genomes, the results showed that the four subfamilies (Nitidulinae, Meligethinae, Carpophilinae, Epuraeinae) of Nitidulidae formed a monophyletic group and further supported the sister group relationship of Nitidulidae + Kateretidae. In addition, the taxonomic status of Meligethinae and the sister group relationship between Meligethinae and Nitidulinae (the latter as currently circumscribed) were also preliminarily explored.

Prime editing using CRISPR-Cas12a and circular RNAs in human cells.

Genome editing with prime editors based on CRISPR-Cas9 is limited by the large size of the system and the requirement for a G/C-rich protospacer-adjacent motif (PAM) sequence. Here, we use the smaller Cas12a protein to develop four circular RNA-mediated prime editor (CPE) systems: nickase-dependent CPE (niCPE), nuclease-dependent CPE (nuCPE), split nickase-dependent CPE (sniCPE) and split nuclease-dependent CPE (snuCPE). CPE systems preferentially recognize T-rich genomic regions and possess a potential multiplexing capacity in comparison to corresponding Cas9-based systems. The efficiencies of the nuclease-based systems are up to 10.42%, whereas niCPE and sniCPE reach editing frequencies of up to 24.89% and 40.75% without positive selection in human cells, respectively. A derivative system, called one-sniCPE, combines all three RNA editing components under a single promoter. By arraying CRISPR RNAs for different targets in one circular RNA, we also demonstrate low-efficiency editing of up to four genes simultaneously with the nickase prime editors niCPE and sniCPE.

Comparative mitochondrial genome analysis of three leafhopper species of the genus Abrus Dai & Zhang (Hemiptera: Cicadellidae: Deltocephalinae) from China with phylogenetic implication

BackgroundThe phylogenetic position and classification of Athysanini are poorly defined, as it includes a large group of polyphyletic genera that have historically been assigned to it mainly because they still exhibit the most typical deltocephaline genitalic and external body characters but lack the distinctive characteristics that other tribes possess. The bamboo-feeding leafhopper genus Abrus belong to the tribe Athysanini of subfamily Deltocephalinae, which currently comprises 19 valid described species, and are limited to the Oriental and Palaearctic regions in China. Although the taxonomy of Abrus are well updated, the references on comparative mitogenomic analyses of Abrus species are only known for a single species. In this study, we sequenced and analyzed the complete mitochondrial genomes (mitogenomes) of Abrus daozhenensis Chen, Yang & Li, 2012 (16,391bp) and A. yunshanensis Chen, Yang & Li, 2012 (15,768bp) (Athysanini), and compared with published mitogenome sequence of A. expansivus Xing & Li, 2014 (15,904bp).ResultsThese Abrus species shared highly conserved mitogenomes with similar gene order to that of the putative ancestral insect with 37 typical genes and a non-coding A + T-rich region. The nucleotide composition of these genomes is highly biased toward A + T nucleotides (76.2%, 76.3%, and 74.7%), AT-skews (0.091 to 0.095, and 0.095), negative GC-skews (− 0.138, − 0.161, and − 0.138), and codon usage. All 22 tRNA genes had typical cloverleaf secondary structures, except for trnS1 (AGN) which lacks the dihydrouridine arm, and distinctively trnG in the mitogenome of A. expansivus lacks the TψC arm. Phylogenetic analyses based on 13 PCGs, 2 rRNA genes, and 22 tRNA genes consistently recovered the monophyletic Opsiini, Penthimiini, Selenocephalini, Scaphoideini, and Athysanini (except Watanabella graminea, previously sequenced species as Chlorotettix nigromaculatus) based on limited available mitogenome sequence data of 37 species.ConclusionAt present, Abrus belongs to the tribe Athysanini based on both morphological and molecular datasets, which is strongly supported in present phylogenetic analyses in both BI and ML methods using the six concatenated datasets: amino acid sequences and nucleotides from different combinations of protein-coding genes (PCGs), ribosomal RNA (rRNAs), and transfer RNA (tRNAs). Phylogenetic trees reconstructed herein based on the BI and ML analyses consistently recovered monophylitic Athysanini, except Watanabella graminea (Athysanini) in Opsiini with high support values.

Comparative and phylogenetic analyses of mitochondrial genomes in Elateridae (Coleoptera: Elateroidea).

The click-beetles (Elateridae) are a species-rich beetle family that is easily recognizable. They are distributed in all zoogeographical regions with over 11,000 species. Comparative studies of the structural characteristics of mitochondrial genomes (mitogenomes), as well as phylogenetic relationships of click-beetles, can improve our understanding of mitogenomic evolution. In this study, we determined four mitogenomes from Elateridae by next-generation sequencing. The four mitogenomes were 16,005 to 16,930 bp in length with 37 typical genes and a control region (A + T-rich region). Combined with previously reported elaterid mitogenomes, all PCGs initiate with either the standard start codon of ATN or TTG. According to the nonsynonymous/synonymous mutation ratio (Ka/Ks) of all PCGs, the highest and the lowest evolutionary rates were found for atp8 and cox1, respectively. Among the control regions of the four mitogenomes, several different patterns and numbers of tandem repeats were identified, which was the primary cause of the length variation in control regions. Phylogenetic analyses were conducted based on 13 protein-coding genes and two ribosomal RNA genes from 33 species of Elateridae and two outgroups. The Bayesian inference and maximum likelihood trees had an identical topological structure. The monophyly of Cardiophorinae, Agrypninae and Elaterinae was recovered with high support in all topologies, and the Tetralobinae was placed as the earliest branch in the Elateridae. Expanding the availability of mitogenomic and genomic data from a broader range of click-beetles could provide more clarity on the disputed relationships among subfamilies within Elateridae.

Characterization of the complete mitochondrial genome of the longhorn beetle, Batocerahorsfieldi (Coleoptera, Cerambycidae) and its phylogenetic analysis with suitable longhorn beetles.

Mitochondrial genome analysis is an important tool for studying insect phylogenetics. The longhorn beetle, Batocerahorsfieldi, is a significant pest in timber, economic and protection forests. This study determined the mitochondrial genome of B.horsfieldi and compared it with the mitochondrial genomes of other Cerambycidae with the aim of exploring the phylogenetic status of the pest and the evolutionary relationships among some Cerambycidae subgroups. The complete mitochondrial genome of B.horsfieldi was sequenced by the Illumina HiSeq platform. The mitochondrial genome was aligned and compared with the existing mitochondrial genomes of Batoceralineolata and B.rubus in GenBank (MF521888, MW629558, OM161963, respectively). The secondary structure of transfer RNA (tRNA) was predicted using tRNAScan-SE server v.1.21 and MITOS WebSever. Thirteen protein-coding genes (PCGs) and two ribosomal RNA gene sequences of 21 longhorn beetles, including B.horsfieldi, plus two outgroups, Dryopsernesti (Dryopidae) and Heterocerusparallelus (Heteroceridae), were analyzed. The phylogenetic tree was constructed using maximum likelihood and Bayesian inference methods. In this study, we successfully obtained the complete mitochondrial genome of B.horsfieldi for the first time, which is 15 425 bp in length. It contains 37 genes and an A + T-rich region, arranged in the same order as the recognized ancestor of longhorn beetles. The genome of B.horsfieldi is composed of 33.12% A bases, 41.64% T bases, 12.08% C bases, and 13.16% G bases. The structure, nucleotide composition, and codon usage of the new mitochondrial genome are not significantly different from other longhorn mitochondrial genomes. Phylogenetic analyses revealed that Cerambycidae formed a highly supported single clade, and Vesperidae was either clustered with Cerambycidae or formed a separate clade. Interestingly, B.horsfieldi, B.rubus and B.lineolata were clustered with Monochamus and Anoplophora species in both analyses, with high node support. Additionally, the VesperidaeSpiniphilusspinicornis and Vesperussanzi and the 19 Cerambycidae species formed a sister clade in the Bayesian analysis. Our results have produced new complete mitogenomic data, which will provide information for future phylogenetic and taxonomic research, and provide a foundation for future relevant research.

Complete mitochondrial genomes of two moths in the tribe Trichaeini (Lepidoptera: Crambidae) and their phylogenetic implications.

The complete mitochondrial genomes of two Prophantis species in the tribe Trichaeini (Lepidoptera: Crambidae) were sequenced using high-throughput sequencing technology. They were assembled and annotated: The complete mitogenomes of P. octoguttalis and P. adusta were 15,197 and 15,714 bp, respectively, and contain 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and an A + T-rich region. Their arrangement was consistent with the first sequenced mitogenome of Bombyx mori (Bombycidae) in Lepidoptera, which had the trnM-trnI-trnQ rearrangement. The nucleotide composition was obviously AT-biased, and all PCGs, except for the cox1 gene (CGA), used ATN as the start codon. Except for trnS1, which lacked the DHU stem, all tRNA genes could fold into the clover-leaf structure. The features of these two mitogenomes were highly consistent with those of other species of Spilomelinae in previous studies. Phylogenetic trees of Crambidae were reconstructed based on mitogenomic data using maximum likelihood and Bayesian inference analysis methods. Results showed that Trichaeini in this study robustly constitute a monophyletic group in Spilomelinae, with the relationships (Trichaeini + Nomophilini) + ((Spilomelini + (Hymeniini + Agroterini)) + Margaroniini). However, the affinities of the six subfamilies Acentropinae, Crambinae, Glaphyriinae, Odontiinae, Schoenobiinae, and Scopariinae within the "non-PS Clade" in Crambidae remained doubtful with unstable topologies or low supports.

Complete mitochondrial genome of the longicorn Anoplophora horsfieldi Hope (Coleoptera: Cerambycidae)

The chinaberry yellow-banded longhorn beetle, Anoplophora horsfieldi Hope 1842 (Coleoptera: Cerambycidae) is an important pest on many economic tree species. In this study, the complete mitochondrial genome of A. horsfieldi was determined, which was 15,837 bp in length and contained 37 genes, including 13 protein-coding genes (PCGs), two rRNA, 22 tRNA genes, and a non-coding A + T-rich region. The phylogenetic analysis based on mitochondrial genomes showed that A. horsfieldi is sister to a clade formed by A. chinensis and A. glabripennis.

New Insights into the Origin and Evolution of Mysmenid Spiders (Araneae, Mysmenidae) Based on the First Four Complete Mitochondrial Genomes.

The mitochondrial genome (mitogenome) is recognized as an effective molecular marker for studying molecular evolution and phylogeny. The family Mysmenidae is a group of widely distributed and covert-living spiders, of which the mitogenomic information is largely unclear. In this study, we obtained the first four complete mitogenomes of mysmenid spiders (one aboveground species: Trogloneta yuensis, and three cave-dwelling species: T. yunnanense, Yamaneta kehen and Y. paquini). Comparative analyses revealed that their lengths ranged from 13,771 bp (T. yuensis) to 14,223 bp (Y. kehen), containing a standard set of 37 genes and an A + T-rich region with the same gene orientation as other spider species. The mitogenomic size of T. yunnanense was more similar to that of Yamaneta mitogenomes than that of T. yuensis, which might indicate the convergent evolution of cave spiders. High variability was detected between the genera Trogloneta and Yamaneta. The A + T content, the amino acid frequency of protein-coding genes (PCGs) and the secondary structures of tRNAs showed large differences. Yamaneta kehen and Y. paquini contained almost identical truncated tRNAs, and their intergenic spacers and overlaps exhibited high uniformity. The two Yamaneta species also possessed a higher similarity of start/stop codons for PCGs than the two Trogloneta species. In selective pressure analysis, compared to Yamaneta, Trogloneta had much higher Ka/Ks values, which implies that selection pressure may be affected by habitat changes. In our study, the phylogenetic analysis based on the combination of 13 PCGs and two rRNAs showed that Mysmenidae is a sister clade to the family Tetragnathidae. Our data and findings will contribute to the better understanding of the origin and evolution of mysmenid spiders.

Phylogenomics including the newly sequenced mitogenomes of two moths (Noctuoidea, Erebidae) reveals Ischyja manlia (incertae sedis) as a member of subfamily Erebinae.

We sequenced the mitogenomes of two Erebid species, namely Ischyja manlia (Cramer, 1776) and Rusicada privata (Walker, 1865) to analyse the phylogenetic relationship and to establish the taxonomic position of incertae sedis members of the family Erebidae. The two circular genomes of I. manlia and R. privata were 15,879bp and 15,563bp long, respectively. The gene order was identical, containing 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and an A + T-rich region. The nucleotide compositions of the A + T-rich region of both mitogenomes were similar: 80.65% for R. privata, and 81.09% for I. manlia. The AT skew and GC skew were slightly positive in I. manlia and negative in R. privata. In I. manlia and R. privata, except for cox1 which started with CGA and TTG codons, all the other 12 PCGs started with ATN codon. The A + T-rich regions of I. manlia and R. privata were 433 and 476bp long, respectively, and contained common characteristics of Noctuoidea moths. At present, Ischyja is treated as Erebinae incertae sedis. However, phylogenetic analysis conducted in the present study reveals that the genus Ischyja is most likely to be a member of the subfamily Erebinae.

The first complete mitochondrial genome sequences for Ulidiidae and phylogenetic analysis of Diptera.

Tetanops sintenisi is a pest that mainly damages the root of quinoa (Chenopodium quinoa) and it is first discovered in China in 2018. Here, the complete mitochondrial genome (mitogenome) of T. sintenisi was sequenced and compared with the mitogenomes of other Diptera species. The results revealed that the mitogenome of T. sintenisi is 15,763bp in length (GenBank accession number: MT795181) and is comprised of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA genes, and a non-coding A + T-rich region (959bp). The highly conserved gene arrangement of the mitogenome of T. sintenisi was identical to that of other Diptera insects. Twelve PCGs contained the typical insect start codon ATN, while cox1 had CGA as the start codon. The genes cox2, nad4, and nad1 contained an incomplete termination codon T; nad3, nad5, and cob contained the complete termination codon TAG; and the remaining seven PCGs contained the termination codon TAA. All tRNA genes were predicted to fold into the typical cloverleaf secondary structure. Phylogenetic analysis of 48 species based on the mitogenome sequence revealed that T. sintenisi clustered with the Tephritidae family, indicating that T. sintenisi and Tephritidae have a close phylogenetic relationship. The phylogenetic relationship of T. sintenisi based on the mitogenome is consistent with the traditional morphological taxonomy, according to which T. sintenisi belongs to the family Otitidae, which is closely related to the family Muscidae.

The complete mitochondrial genome of Nasutitermes tiantongensis Zhou et Xu, 1993 (Isoptera: Termitidae: Nasutitermitinae)

Nasutitermes tiantongensis belongs to Nasutitermitinae and its mitochondrial genome was determined in this study. It consisted of 13 PCGs, 22 tRNAs, 2 rRNAs, and an A + T-rich control region, and its length was 15824 bp. The phylogenetic analysis suggested that the genus Nasutitermes was not monophyletic, and N. tiantongensis formed a sister group with Bultitermes laticephalus. The mitochondrial genome of N. tiantongensis provides a resource for evolutionary analysis within Nasutitermitinae.

Mitochondrial genome characterization and phylogeny of Wallacea dactyliferae Maulik 1919 (Coleoptera: Chrysomelidae) from China

Wallacea dactyliferae Maulik 1919 (Coleoptera: Chrysomelidae) has been reported as a new invasive palm pest in Asia recently. So far, a total of 29 species have been reported in Wallacea. In the present study, the whole mitochondrial genome of W. dactyliferae was identified for the first time (also for the first species of Wallacea) by using high throughput sequencing systems. The entire genome is 16,243 bp in length (ACCN: OK513040) consisting of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and an A + T-rich region. Phylogenetic analysis revealed that insects from the same subfamily were clustered together, with W. dactyliferae being clustered together with other Cassidinae species. This study can provide essential DNA molecular data for further phylogenetic and evolutionary analyses for Chrysomelidae family of the Coleoptera order.

Comparative mitochondrial genomic analysis provides new insights into the evolution of the subfamily Lamiinae (Coleoptera: Cerambycidae)

The genus Monochamus within the subfamily Lamiinae is the main vector of Bursaphelenchus xylophilus, which causes pine wilt disease and induces substantial economic and ecological losses. Only three complete mitochondrial genomes of the genus Monochamus have been sequenced to date, and no comparative mitochondrial genomic studies of Lamiinae have been conducted. Here, the mitochondrial genomes of two Monochamus species, M. saltuarius and M. urussovi, were newly sequenced and annotated. The composition and order of genes in the mitochondrial genomes of Monochamus species are conserved. All transfer RNAs exhibit the typical clover-leaf secondary structure, with the exception of trnS1. Similar to other longhorn beetles, Lamiinae mitochondrial genomes have an A + T bias. All 13 protein-coding genes have experienced purifying selection, and tandem repeat sequences are abundant in the A + T-rich region. Phylogenetic analyses revealed congruent topologies among trees inferred from the five datasets, with the monophyly of Acanthocinini, Agapanthiini, Batocerini, Dorcaschematini, Pteropliini, and Saperdini receiving high support. The findings of this study enhance our understanding of mitochondrial genome evolution and will provide a basis for future studies of population genetics and phylogenetic investigations in this group.

Next-Generation Sequencing of Four Mitochondrial Genomes of Dolichovespula (Hymenoptera: Vespidae) with a Phylogenetic Analysis and Divergence Time Estimation of Vespidae.

The wasp genus Dolichovespula (Hymenoptera: Vespidae: Vespinae) is a eusocial wasp group. Due to the taxonomic and phylogenetic issues with the family Vespidae, more genetic data should be gathered to provide efficient approaches for precise molecular identification. For this work, we used next-generation sequencing (also known as high-throughput sequencing) to sequence the mitochondrial genomes (mtgenomes) of four Dolichovespula species, viz. D. flora, D. lama, D. saxonica, and D. xanthicincta 16,064 bp, 16,011 bp, 15,682 bp, and 15,941 bp in length, respectively. The mitochondrial genes of the four species are rearranged. The A + T content of each mtgenome is more than 80%, with a control region (A + T-rich region), 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes. There are 7 to 11 more genes on the majority strands than on the minority strands. Using Bayesian inference and Maximum-Likelihood methodologies as well as data from other species available on GenBank, phylogenetic trees and relationship assessments in the genus Dolichovespula and the family Vespidae were generated. The two fossil-based calibration dates were used to estimate the origin of eusociality and the divergence time of clades in the family Vespidae. The divergence times indicate that the latest common ancestor of the family Vespidae appeared around 106 million years ago (Ma). The subfamily Stenogastrinae diverged from other Vespidae at about 99 Ma, the subfamily Eumeninae at around 95 Ma, and the subfamily Polistinae and Vespinae diverged at approximately 42 Ma. The genus Dolichovespula is thought to have originated around 25 Ma. The origin and distribution pattern of the genus Dolichovespula are briefly discussed.

Characterization of the complete mitochondrial genome of Cryptotermes domesticus (Blattodea: Kalotermitidae): Genome description and phylogenetic implications.

The complete mitochondrial genome of Cryptotermes domesticus (Haviland) was sequenced and annotated to study its characteristics and the phylogenetic relationship of C. domesticus to other termite species. The mitogenome of C. domesticus is a circular, close, and double-stranded molecule with a length of 15,655 bp. The sequenced mitogenome contains 37 typical genes, which are highly conserved in gene size, organization, and codon usage. Transfer RNA genes (tRNAs) also have typical secondary structures. All of the 13 protein-coding genes (PCGs) start with an ATN codon, except for nad4, which starts with GTG and terminates with the terminal codon TAA and TAG or the incomplete form T-- (cox2 and nad5). Most tRNAs have a typical cloverleaf structure, except for trnS1, in which this form is replaced by a simple loop and lacks the dihydrouridine (DHU) arm. The nucleotide diversity (Pi) and nonsynonymous (Ka)/synonymous (Ks) mutation rate ratios indicate that nad1, cox1, and cox3 are the most conserved genes, and that cox1 has the lowest rate of evolution. In addition, an 89 bp repeated sequence was found in the A + T-rich region. Phylogenetic analysis was performed using Bayesian inference (BI) and maximum likelihood (ML) methods based on 13 PCGs, and the monophyly of Kalotermitidae was supported.

The first complete mitochondrial genome in the family Attevidae (Attevaaurea) of the order Lepidoptera.

The superfamily Yponomeutoidea, one of the early-derived groups in the order Lepidoptera, consists of 11 families. However, mitochondrial genome (mitogenome) sequences, popularly used for phylogeny and evolutionary tracing, are available for only seven species across six genera and five families. Thus, a larger variety of mitogenome sequences in Yponomeutoidea are required to improve our understanding of lepidopteran phylogeny and genomic evolution. In this study, we present the complete mitogenome of Attevaaurea (Fitch, 1856), the first species in the family Attevidae (superfamily Yponomeutoidea, order Lepidoptera) to be sequenced. The complete mitogenome comprises 16,329 bp and contains a typical set of genes and one non-coding region. Within Yponomeutoidea, the mitogenome of A.aurea has a unique trnI-trnM-trnQ arrangement at the A + T-rich region and ND2 junction and trnA-ND3 arrangement at the trnG and trnR junction. Twelve of the 13 protein-coding genes (PCGs) of A.aurea have a typical ATN starting codon, whereas COI has the atypical CGA codon, which is frequently found in the starting region of lepidopteran COI. Phylogenetic analyses, based on the concatenated sequences of 13 PCGs and two rRNA genes, using the Maximum Likelihood method, revealed a sister relationship between Attevidae and Praydidae with moderately low nodal support (bootstrap support = 64%).