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Gomphomastacinae is a grasshopper subfamily in Eumastacidae, with a morphology and distribution distinct from other subfamilies. The alpine genera of Gomphomastacinae that inhabit the Qinghai–Tibet Plateau in China show unique characteristics adapted to high‐altitude life. However, their phylogenetic position and biogeographic history remain controversial. Thus, to determine the diversification history of these alpine genera and the origin of the subfamily, we obtained mitochondrial genome sequences from all seven Gomphomastacinae genera distributed in China. The reconstructed phylogeny was well supported and confirmed the phylogenetic position of Gomphomastacinae within Eumastacidae. Time calibration revealed a deep‐time origin of the subfamily dating back to the Cretaceous period, and the diversification among alpine genera was also an ancient pre‐Miocene event (30–50 Ma). Based on phylogeny and time estimates, the most likely biogeographic scenario is that Gomphomastacinae originated from an ancestral lineage that lived in East Gondwana and dispersed to Central and Western Asia through India. Subsequently, the alpine genera likely diverged along with the uplift of the Qinghai–Tibet Plateau and survived drastic climate change by in situ adaptation to high‐altitude dwellings. [ABSTRACT FROM AUTHOR]

Tachycines meditationis (Orthoptera: Rhaphidophoridae: Tachycines) is a widely distributed insect in eastern Asia. This species is common in urban environments, and its unique omnivorous diet may contribute to its success in various habitats. However, molecular studies on the species are scarce. Here, we obtained the first transcriptome sequence of T. meditationis and performed preliminary analyses to test whether the evolution of coding sequences fits the expectations based on the species' ecology. We retrieved 476,495 effective transcripts and annotated 46,593 coding sequences (CDS). We analysed the codon usage and found that directional mutation pressure was the leading cause of codon usage bias in this species. This genome-wide relaxed codon usage pattern in T. meditationis is surprising, given the potentially large population size of this species. Moreover, despite the omnivorous diet, the chemosensory genes of this species do not exhibit codon usage deviating significantly from the genome-level pattern. They also do not seem to experience more gene family expansion than other cave cricket species do. A thorough search for rapidly evolved genes using the dN/dS value showed that genes associated with substance synthesis and metabolic pathways, such as retinol metabolism, aminoacyl-tRNA biosynthesis, and fatty acid metabolism, underwent species-specific positive selection. While some results seem to contradict the species ecology, our transcriptome assembly provides a valuable molecular resource for future studies on camel cricket evolution and molecular genetics for feeding ecology in insects, in general. [ABSTRACT FROM AUTHOR]

The taxonomic status of the Pyrgomorphid genera Parapetasia Bolívar, 1884, and Loveridgacris Rehn, 1954 is complex and challenging. Here, we use a combination of morphological, distributional, and genetic data to revise the two genera and provide new information on their diversity. We describe a new species, Loveridgacris tectiferus sp. nov., from Tanzania and formally resurrect the status of Parapetasia rammei as a valid species within Parapetasia, resulting in two species in Parapetasia (P. femorata and P. rammei) and two in Loveridgacris (L. impotens and L. tectiferus sp. nov.). We also sequenced the COI and 16S genes of 10 Pyrgomorphidae species and provided the first phylogeny of the group. Our data show that all species are clearly distinct and represent molecular operational taxonomic units (mOTUs), with the exceptions of L. impotens and L. tectiferus sp. nov., which are morphologically clearly distinct but for which the concatenated sequence alignments of the two individual gene datasets (COI and 16S) do not provide sufficient information. In addition, high interspecific distances were found between Parapetasia and Loveridgacris. Moreover, the complete mitogenomes of L. impotens and L. tectiferus sp. nov. were sequenced using next-generation sequencing technology. The total lengths of the assembled mitogenomes were 15,592 bp and 15,737 bp, representing 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and one D-loop region, respectively. To aid in identification, we present a key for the two genera, including a key to species. This study provides insights into the morphology, distribution, and phylogeny of Pyrgomorphidae in Africa. [ABSTRACT FROM AUTHOR]

Based on whole-genome Illumina sequencing data, the complete mitogenome of the Asiatic SalamanderBatrachuperus tibetanuswas reconstructed and characterized. The circular genome is 16,375 bp in length, and typically consists of 37 genes, including 13 protein coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. Coding genes (PCGs, tRNAs & rRNAs) pieces is 15,460 bp in length, accounting for 94.41% of the total length of genome. The nucleotide composition is asymmetric (34.1% A, 19.5% C, 13.7% G, 32.7% T) with an overall GC content of 33.2%. Comparing our research data with predecessors' previous work, significant changes was found with 94.0% of whole genome sequence consistency percentage (Pairwise % Identity). We suggest our data would contribute to the evolutionary studies of this and related Asiatic Salamanders species. [ABSTRACT FROM AUTHOR]

The complete mitogenome of the geophilous grasshopperTrilophidia annulatawas reconstructed from whole-genome Illumina sequencing data. After annotation, the circular genome was obtained with 16,501 bp in length, and typically consisted of 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. All PCGs were initiated with ATN codons, except ND2 with the start codon GTG. Most of the PCGs used TAA as their stop codons, while the others used TAG as stop codons (COX1, COX3&ND1). The nucleotide composition was asymmetric (42.3% A, 15.0% C, 11.0% G, 31.8% T) with an overall GC content of 25.9%. These data would contribute to the design of novel molecular markers for population and evolutionary research ofT. annulata. [ABSTRACT FROM AUTHOR]

• This study examines customer co-creation value in Chinese short-video platform industry. • This research reveals the relationship between customer co-creation value and electronic word-of-mouth. • Customer-based brand equity are mediator in relationship between customer co-creation value and electronic word-of-mouth. • Psychological ownership mediates the relationship between customer co-creation value and electronic word-of-mouth. The short-video platform industry is a relatively new global industry with a considerable number of users attracted by electronic word-of-mouth (eWOM). User-generated content, which is a form of customer co-creation value (CCCV), is considered as the essence of short-video platforms. This study investigated the effects of CCCV on psychological ownership, customer-based brand equity, and eWOM in relation to short-video platforms. Examination of 337 users on Chinese short-video platforms revealed the underlying mechanism of the shift from CCCV to eWOM in the short-video platform industry by identifying the direct, indirect, and total effects of four research constructs. This study demonstrated that a well-designed co-creation value strategy is a potent reflection of a platform's customers that enhances CCCV for short-video platforms and transforms customers into intangible assets for eWOM. [ABSTRACT FROM AUTHOR]

Most butterflies feed on nectar, while some saprophagous butterflies forage on various non-nectar foods. To date, little is known about the genomic and molecular shifts associated with the evolution of the saprophagous feeding strategy. Here, we assembled the high-quality chromosome-level genome of Hestina assimilis to explore its saprophagous molecular and genetic mechanisms. This chromosome-level genome of H. assimilis is 412.82 Mb, with a scaffold N50 of 15.70 Mb. In total, 98.11% of contigs were anchored to 30 chromosomes. Compared with H. assimilis and other Nymphalidae butterflies, the genes of metabolism and detoxification experienced expansions. We annotated 80 cytochrome P450 (CYP) genes in the H. assimilis genome, among which genes belonging to the CYP4 subfamily were significantly expanded (p < 0.01). These P450 genes were unevenly distributed and mainly concentrated on chromosomes 6–9. We identified 33 olfactory receptor (OR), 20 odorant-binding protein (OBP), and six gustatory receptor (GR) genes in the H. assimilis genome, which were fewer than in the nectarivorous Danaus plexippus. A decreased number of OBP, OR, and GR genes implied that H. assimilis should resort less to olfaction and gustation than their nectarivorous counterparts, which need highly specialized olfactory and gustatory functions. Moreover, we found one site under positive selection occurred in residue 996 (phenylalanine) of GR genes exclusive to H. assimilis, which is conservative in most lineages. Our study provides support for the adaptive evolution of feeding habits in butterflies. [ABSTRACT FROM AUTHOR]

The mole cricket Gryllotalpa orientalis is an evolutionarily, medicinal, and agriculturally significant insect that inhabits underground environments and is distributed globally. This study measured genome size by flow cytometry and k-mer based on low-coverage sequencing, and nuclear repetitive elements were also identified. The haploid genome size estimate is 3.14 Gb by flow cytometry, 3.17 Gb, and 3.77 Gb-based two k-mer methods, respectively, which is well within the range previously reported for other species of the suborder Ensifera. 56% of repetitive elements were found in G. orientalis, similar to 56.83% in Locusta migratoria. However, the great size of repetitive sequences could not be annotated to specific repeat element families. For the repetitive elements that were annotated, Class I-LINE retrotransposon elements were the most common families and more abundant than satellite and Class I-LTR. These results based on the newly developed genome survey could be used in the taxonomic study and whole genome sequencing to improve the understanding of the biology of G. orientalis. [ABSTRACT FROM AUTHOR]

Gene arrangement (relative location of genes) is another evolutionary marker of the mitogenome that can provide extensive information on the evolutionary mechanism. To explore the evolution of gene arrangements in the mitogenome of diversified Ensifera, we sequenced the mitogenome of the unique dune cricket species found in China and used it for phylogenetic analysis, in combination with 84 known Ensiferan mitogenomes. The mitogenome of Schizodactylus jimo is a 16,428-bp circular molecule that contains 37 genes. We identified eight types of gene arrangement in the 85 ensiferan mitogenomes. The gene location changes (i.e., gene translocation and duplication) were in three gene blocks: I-Q-M-ND2, rrnl-rns-V, and ND3-A-R-N-S-E-F. From the phylogenetic tree, we found that Schizodactylus jimo and most other species share a typical and ancient gene arrangement type (Type I), while Grylloidea has two types (Types II and III), and the other five types are rare and scattered in the phylogenetic tree. We deduced that the tandem replication–random loss model is the evolutionary mechanism of gene arrangements in Ensifera. Selection pressure analysis revealed that purifying selection dominated the evolution of the ensiferan mitochondrial genome. This study suggests that most gene rearrangements in the ensiferan mitogenome are rare accidental events. [ABSTRACT FROM AUTHOR]

Xanthium sibiricum has been used widely in Chinese medicine for many years. Although of medicinal value, some species in the Xanthium are reported to be toxic and thus correct identification is essential. Whereas previous identification methods based on molecular characteristics are insufficient for in-depth authentication, chloroplast genome sequences provide more information that can assist in genome-wide evolutionary research. In this study, we sequenced complete chloroplast (cp) genome of X. sibiricum using next-generation sequencing technology and the complete sequence was deposited in Genbank with the accession number MH473582. This is the first reported sequence for the complete cp genome of Xanthium. The complete X. sibiricum cp genome is 151,897 bp in length, comprising one pair of inverted repeats (IRs) of 24,905 bp, separated by one small single copy region (SSC; 17,900 bp) and one large single copy region (LSC; 84,187 bp). The genome contains 115 unique genes, which code for 81 proteins, four rRNAs and 30 tRNAs. All four rRNA genes and seven tRNA genes, ycf15, ycf2, rpl2, rps12, rpl23, ndhB and rps7, are duplicated in the IR regions. The X. sibiricum cp genome has 40 repeat sequences and 59 simple sequence repeat (SSR) loci. Both Maximum parsimony (MP) and maximum likelihood (ML) trees provide very strong bootstrap support (100%) for the sister relationship of X. sibiricum with Ambrosia in the subtribe Ambrosiinae. Our study provides molecular information for further studies with which to identify X. sibiricum among closely related species and other angiosperms. [ABSTRACT FROM AUTHOR]

The medicinal utility of leeches has been demonstrated through decades of use in modern hospital settings, mainly as relievers of venous congestion following flap or digit replantation surgery. In the present study, we sequence and annotate (through BLAST‐ and Gene Ontology‐based approaches) the salivary transcriptome of the nonblood feeding hirudinid Whitmania pigra and assess the differential gene expression of anticoagulation factors (through both quantitative real‐time PCR [qRT‐PCR] and in silico‐based methods) during feeding and fasting conditions. This was done in order to evince the diversity of putative anticoagulation factors, as well as estimate the levels of upregulation of genes immediately after feeding. In total, we found sequences with demonstrated orthology (via both phylogenetic analyses and BLAST‐based approaches) to seven different proteins that have previously been linked to anticoagulatory capabilities—eglin C, bdellin, granulin, guamerin, hyaluronidase, destabilase I, and lipocalin. All of these were recovered from leeches both in the fasting and in the feeding conditions, but all show signs of upregulation in the feeding leeches. Interestingly, our RNA‐seq effort, coupled with a hypergeometric test, indicated that the differentially expressed genes were disproportionately involved in three main immunological pathways (endocytosis, peroxisome regulation, and lysosome regulation). The results and implications of the finding of anticoagulants in this nonblood feeding leech and the putative upregulation of anticoagulation factors after feeding are briefly discussed in an evolutionary context. [ABSTRACT FROM AUTHOR]

The whole-genome Illumina sequence of the Chinese endemic grasshopperFruhstorferiola kulingamitogenome was constructed and reported in this study. In all, the circular genome was obtained with 15,655 bp in length and contains 75.4% A + T. It typically consists of 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. All PCGs are initiated with ATN codons. Most of the PCGs use TAA as their stop codons, while the others use TAG as stop codons (COX1andND1). The size of the large and small ribosomal RNA genes are 1314 bp and 851 bp. The A + T-rich region (777 bp) showed strong resemblance to the other known Orthoptera insects. Our data would contribute to confirm the close relationship and other evolutionary researches of theF. kulinga. [ABSTRACT FROM AUTHOR]

The complete mitogenome ofOxya intricate(Stål.) has been reconstructed from whole-genome Illumina sequencing data with an average coverage of 294×. The circular genome is 15,466 bp in length, and consists of 22 transfer RNAs (tRNAs), 13 protein-coding genes (PCGs), 2 ribosomal RNAs (rRNAs) and 1 D-loop region. All PCGs are initiated with ATN codons, and are terminated with TAR codons except for ND5 with the incomplete stop codon T. The nucleotide composition is asymmetric (42.5%A, 14.6%C, 10.6%G, 32.3%T) with an overall GC content of 25.2%. These data would contribute to the design of novel molecular markers for population and evolutionary studies of this and related orthopteran species. [ABSTRACT FROM AUTHOR]

Background: Hirudinaria manillensis is an ephemeral, blood-sucking ectoparasite, possessing anticoagulant capacities with potential medical applications. Analysis of codon usage patterns would contribute to our understanding of the evolutionary mechanisms and genetic architecture of H. manillensis , which in turn would provide insight into the characteristics of other leeches. We analysed codon usage and related indices using 18,000 coding sequences (CDSs) retrieved from H. manillensis RNA-Seq data. Results: We identified four highly preferred codons in H. manillensis that have G/C-endings. Points generated in an effective number of codons (ENC) plot distributed below the standard curve and the slope of a neutrality plot was less than 1. Highly expressed CDSs had lower ENC content and higher GC content than weakly expressed CDSs. Principal component analysis conducted on relative synonymous codon usage (RSCU) values divided CDSs according to GC content and divided codons according to ending bases. Moreover, by determining codon usage, we found that the majority of blood-diet related genes have undergone less adaptive evolution in H. manillensis , except for those with homologous sequences in the host species. Conclusions: Codon usage in H. manillensis had an overall preference toward C-endings and indicated that codon usage patterns are mediated by differential expression, GC content, and biological function. Although mutation pressure effects were also notable, the majority of genetic evolution in H. manillensis was driven by natural selection. [ABSTRACT FROM AUTHOR]

The electronic conduction through the self-assembled monolayer (SAM) can be modulated by the electric potential applied to the silicon gate electrode surrounding the SAM. The dependence of the current through SAM on the gate voltage can be explained that the renormalized molecular energy levels are swept through the window between the Fermi levels of the source and drain electrodes. The effects of the lowest unoccupied molecular orbital and a hybrid energy level near the Fermi level in the transmission spectrum can be identified. [ABSTRACT FROM AUTHOR]

Background: Cadmium (Cd)-containing chemicals can cause serious damage to biological systems. In animals and plants, Cd exposure can lead to metabolic disorders or death. However, for the most part the effects of Cd on specific biological processes are not known. DNA methylation is an important mechanism for the regulation of gene expression. In this study we examined the effects of Cd exposure on global DNA methylation in a living organism by whole-genome bisulfite sequencing (WGBS) using Drosophila melanogaster as model. Results: A total of 71 differentially methylated regions and 63 differentially methylated genes (DMGs) were identified by WGBS. A total of 39 genes were demethylated in the Cd treatment group but not in the control group, whereas 24 showed increased methylation in the former relative to the latter. In most cases, demethylation activated gene expression: genes such as Cdc42 and Mekk1 were upregulated as a result of demethylation. There were 37 DMGs that overlapped with differentially expressed genes from the digital expression library including baz, Act5C, and ss, which are associated with development, reproduction, and energy metabolism. Conclusions: DNA methylation actively regulates the physiological response to heavy metal stress in Drosophila in part via activation of apoptosis. [ABSTRACT FROM AUTHOR]

Damselflies and dragonflies, of the order Odonata, have distinct body plans and predatory abilities. Knowledge of their various evolutionary histories will allow for an understanding of the genetic and phenotypic evolution of insects. Mitogenomes are suitable materials to elucidate this, but the mitogenome of only a few odonates have been annotated. Herein, we report the complete mitogenome of nine odonates, including seven dragonflies and two damselflies, and a comprehensive analysis of the codon usage in 31 Odonata mitogenomes with the aim to estimate their evolutionary characteristics. Overall, a weak codon bias exists among odonate mitogenomes, although this favours AT-ending codons. Damselflies have a weaker codon usage bias than dragonflies, and 37 codons have significantly different usages. Both directional mutation and purifying selection shape damselfly and dragonfly mitogenomes. Although inevitable, directional mutation bias plays a minor role, whereas purifying selection pressure is the dominant evolutionary force. A higher selection pressure is observed in dragonflies than in damselflies, but it mainly acts on codon usage patterns rather than amino acid translation. Our findings suggest that dragonflies might have more efficient mitochondrial gene expression levels than damselflies, producing more proteins that support their locomotion and predatory abilities. [ABSTRACT FROM AUTHOR]