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Abstract The complete mitochondrial genome (mitogenome) of Periplaneta brunnea was sequenced in this study and used to reconstruct the phylogenetic relationship of Blattodea. The circular mitogenome was 15,604 bp long and exhibited typical gene organization and order, consistent with other sequenced Periplaneta mitogenomes. The initiation codon of the P. brunnea COX1 gene was unusual in that no typical ATN or TTG start codon was found. The two longest intergenic spacer sequences found in the P. brunnea mitogenome were 21 and 17 bp long. Twenty-one base spacer had a 4 bp motif (TATT) between tRNA-Glu and tRNA-Met that conservatively displayed in 9 sequenced blattarian mitogenomes. The second spacer was between tRNA-Ser ( UCN ) and NAD1 containing a 7 bp motif (WACTTAA) that was highly conserved in 14 blattarian mitogenomes. The control region showed a relatively fixed motif present in 6 Blattidae mitogenomes, with a big stem-loop structure. Phylogenetic analyses were conducted using site-homogeneous models based on 13 protein-coding genes (PCGs) and two RNA genes. The trees derived from Bayesian inference and maximum likelihood analyses and recovered a relatively stable relationship among major lineages except for the position of Polyphagidae and inter-family relationships of Blaberidae. Analyses supported the monophyly of Blattidae, Blaberidae, Blattellidae, Polyphagidae, Dictyoptera, and the paraphyly of Blattaria. We also found Mantodea was the sister clade to (Blattaria + Isoptera), being the basal position of Dictyoptera in all topologies. Meanwhile, our results also consistently supported that Isoptera should be clustered with Blattaria of Blattodea. Graphical abstract Unlabelled Image Highlights • The complete mitogenome of P. brunnea was sequenced. • The initiation codon of the P. brunnea COX 1 gene was unusual. • Two motifs were found in intergenic spacer sequences of P. brunnea mitogenome. • The control region of P. brunnea had a big stem-loop structure. • Phylogenetic inference method and dataset had effect on the position of Polyphagidae. [ABSTRACT FROM AUTHOR]

Trueperella pyogenes is a gram-positive opportunistic pathogen normally causes mastitis, liver abscesses and pneumonia of economically important livestock. It has been suggested that gram-negative bacteria can suppress the growth and virulence of T. pyogenes in vitro by using the quorum-sensing (QS) signal molecules and cause the transition of predominant species. However, whether these QS signals can be used as potential anti-virulence drugs against T. pyogenes infection is unclear. In this study, the in vivo inhibitory effect N -acyl homoserine lactones (AHLs) from Escherichia coli and Pseudomonas aeruginosa on T. pyogenes was tested by using mouse model. Mice were first peritoneally infected with T. pyogenes followed by intravenous injection of N -Octanoyl-DL-homoserine lactone (C8HSL) or N -(3-oxododecanoyl) homoserine- l -lactone (C12HSL). The results showed that C8HSL and C12HSL significantly reduced bacterial load and increased the survival rate of mice against T. pyogenes challenge. Additionally, the treatment of AHLs promoted the secretion of IL-1β, IL-6, IL-8 and TNF-α in mouse peritoneal fluid, and significantly decreased the expression levels of virulence genes of residual T. pyogenes . Importantly, murine macrophages rapidly phagocytosed bacteria when they were treated with AHLs compared to untreated cells. Collectively, our findings provide a major advance in understanding the inhibitory effect of AHLs in vivo and a promise for developing new clinical or veterinary treatments of T. pyogenes -related infection. [ABSTRACT FROM AUTHOR]

Using high-throughput first-principles calculations, combined with self-consistent phonon theory and Boltzmann transport equations, the lattice thermal transport properties of fluoride perovskites XHgF 3 (X = K, Rb) with strong anharmonicity are investigated. After considering the quartic anharmonic renormalization, the imaginary frequency in the phonon spectrum disappears and the low-lying modes soften, resulting in a low group velocity of the acoustic phonons. The strong quartic anharmonicity also causes extremely strong four-phonon scattering, which is even greater than three-phonon scattering in the low frequency phonon mode. The results show that the lattice thermal conductivity κ L of XHgF 3 (X = K, Rb) is ultra-low and the temperature dependence is unusually weak. The κ L of KHgF 3 at 300 K is only 0.18 Wm−1K−1, which is one-fifth of the classical low thermal conductivity material, quartz glass. Our study points the way to addressing the thermal transport properties of materials with strong anharmonicity and demonstrates that XHgF 3 (X = K, Rb) can not only serve as a good thermal insulation material but also has potential applications in the thermoelectric field. • Fluoride perovskites XHgF 3 (X = K, Rb) have strong quartic anharmonicity. • The frequency of the low-lying modes is significantly boosted after considering the quartic anharmonic renormalization. • The low-frequency four-phonon scattering of XHgF 3 (X = K, Rb) is even stronger than the three-phonon scattering. • XHgF 3 (X = K, Rb) have ultra-low lattice thermal conductivity and unusually weak temperature dependence. • The lattice thermal conductivities of KHgF 3 and RbHgF 3 are much lower than that of the classical thermoelectric material PbTe. [ABSTRACT FROM AUTHOR]

Harvest Mouse ( Micromys minutus ) has a very wide range of distribution in Asia and Europe. However, the phylogenetic relationship of M. minutus is still uncertain. In this study, we determined the complete mitochondrial (mt) genome sequences of M. minutus , and used the complete mitochondrial genome sequences constructed the phylogenetic tree of Muroidea. The size of the genome is 16,232 bp in length and has a base composition of 33.6% A, 29.1% T, 24.8% C, and 12.5% G. The mitogenome structure was similar to that of typical vertebrate and other rodents' mitochondrial genomes, includes 13 protein-coding genes, 2 rRNA genes (12S rRNA and 16S rRNA), 22 tRNA genes, and 1 control region. We suggested a new initiation codon for ND5 (NADH dehydrogenase subunit), which has been never reported in the mitochondrial genome of vertebrate. The ML and BI phylogenetic trees, which based on the combination of the 12 protein-coding genes, supported strongly that the genus Micromys was represent an early offshoot within the Muridae with high support values (BI = 1.00, ML = 100). [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome sequence of Accipiter virgatus was determined. This mt-genome was 17,952 bp in length and consisted of 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes, one control region (CR) and one pseudo-control region (CCR). Phylogenetic analyses of 14,644 bp of mitochondrial DNA (12 protein-coding genes, 2 rRNAs and 22 tRNAs) revealed the phylogenetic position of Cathartidae ( Cathartes aura ) was more closer to Ciconiidae (storks) than Accipitridae. To investigate the divergence times of the CCRs in Falconiformes, detailed analyses of the noncoding regions (CR and CCR) were performed. We found the recently reported novel gene order in Falconiformes had multiple independent origins and hence cannot be used to infer phylogenetic lineages. Indeed, the molecular clock suggested the CCR in Falconidae emerged about 65.4 million years (Mya), while that in Pandionidae–Accipitridae clade emerged about 19.16 Mya. The intra-genomic homology between the noncoding regions was detected in Spilornis cheela , which supporting the duplication hypothesis. Furthermore, the structure of CCR should be featured by a region containing tandem repeats as two definitely separated clusters of tandem repeats were found. The findings presented here should be considered in future phylogenetic and evolutionary studies targeting the pseudo-control regions of all Falconiformes species. [ABSTRACT FROM AUTHOR]

• SSR distribution patterns across 29 beetle genomes were analyzed. • The number of SSRs was positively correlated with beetle genome size. • Common genomic features of P-SSRs in beetle genomes were rare. • Functional analysis of CDSs containing P-SSRs in beetle genomes were performed. Simple sequence repeats (SSRs) represent an important source of genetic variation that provides a basis for adaptation to different environments in organisms. In this study, we examined the distribution patterns of SSRs in twenty-nine beetle genomes and carried out Gene Ontology (GO) analysis of CDSs embedded with perfect SSRs (P-SSRs). The results demonstrated that imperfect SSRs (I-SSRs) represented the most abundant SSR category in beetle genomes and in different genomic regions (CDS, exon, and intron regions). The numbers of P-SSRs, I-SSRs, compound SSRs, and variable number tandem repeats were positively correlated with beetle genome size, whereas neither the frequency nor the density of the SSRs was correlated with genome size. Moreover, our results demonstrated that common genomic features of P-SSRs within the same suborder or family of Coleoptera were rare. Mono-, di-, tri-, or tetranucleotide SSRs were the most abundant P-SSR categories in beetle genomes. The preferred predominant repeat motif among the mononucleotide P-SSRs was (A)n, but the most frequent repeat motifs for other length classes varied differentially among these genomes. Furthermore, the P-SSR type with the highest GC content differed in the beetle genomes and in different genomic regions. CV (coefficient of variability) analysis demonstrated that the repeat copy numbers of P-SSRs presented relatively higher variation in introns than in CDSs and exons. The GO terms of CDSs containing P-SSRs for molecular functions were mainly enriched in "binding" and "transcription". Our findings will be useful for studying the functional roles of microsatellite heterogeneity in beetle adaptation. [ABSTRACT FROM AUTHOR]

• mTOR is significantly expressed in liver transcriptome during T. pyogenes infection. • The inhibition of mTOR induced autophagy and reduced bacterial burdens in vitro. • The inhibition of mTOR regulated oxidation and cytokine against T. pyogenes in vitro. • The inhibition of mTOR protected mice against T. pyogenes challenge. Trueperella pyogenes is an importantly opportunistic and commensal pathogen that causes suppurative lesions of most economically important livestock. To understand the molecular mechanism underlying the infection by T. pyogenes , we carried out a large-scale transcriptome sequencing of mice livers intraperitoneally infected with T. pyogenes using RNA-sequencing. A total of 47 G clean bases were obtained and 136 differentially expressed genes were detected between the control and the infection groups in the liver transcriptomes. Additionally, we found that the expression of a key autophagy regulator, mTOR (mechanistic target of rapamycin) was significantly up-regulated in the infection groups. Mechanistically, T. pyogenes infection induced the expression of mTOR and subsequently inhibited the autophagy of host cell. Blocking autophagy with inhibitor 3-methyladenine (3-MA) or silencing autophagy-related gene 7 (Atg7) reduced the effect of bacterial elimination. Interestingly, inhibition of mTOR induced autophagy and reduced T. pyogenes viability in RAW264.7 murine macrophages. The silencing mTOR regulated oxidation and cytokines (interleukin-1β, IL-6 and tumor necrosis factro-α) against T. pyogenes in macrophages and significantly protected mice from T. pyogenes challenge. These findings indicate that mTOR is a novel functional regulator in autophagy-mediated T. pyogenes elimination and will be useful to further knowledge on the development of effective therapeutic strategy to control T. pyogenes -related diseases. [ABSTRACT FROM AUTHOR]

The blister beetle is an important resource insect due to its defensive substance cantharidin, which was widely used in pharmacology and plant protection. We determined the complete mitochondrial genome of Epicauta chinensis Laporte (Coleoptera: Tenebrionoidae: Meloidae). The circular genome is 15,717 bp long, encoding 13 protein-coding genes (PCGs), two ribosomal RNAs and 22 tRNAs and containing a A + T-rich region with gene arrangement identical to other Coleopteran species. Twelve PCGs start with typical ATN codon, while ATP8 gene initiate with GTT for first report in Insecta. All PCGs terminate with conventional stop codon TAA or TAG. All tRNAs in E. chinensis are predicted to fold into typical cloverleaf secondary structure, except tRNA-Ser(AGN), in which the dihydrouracil arm (DHU arm) could not form stable stem-loop structure. The secondary structure of lrRNA and srRNA comprises 48 helices and 32 helices respectively. The 1101 bp A + T-rich region contains a 15 bp poly-T stretch and microsatellite-like repeats rather than large tandem repetitive sequences. Phylogenetic analysis, based on 13 PCGs of 45 Coleopteran species, show that E. chinensis grouped with Tenebrionidae species. It also support the topology of (((Chrysomelidae + Curculionoidea) + (Cucujoidea + Cleroidea)) + Tenebrionoidea) within Cucujiformia. [ABSTRACT FROM AUTHOR]

Sichuan Hill Partridge ( Arborophila rufipectus ) is a globally endangered species endemic to China. However, the genetic diversity of this species was poorly studied due to lack of molecular markers. We used 454 pyrosequencing to discover microsatellites from the A . rufipectus genome in this study. A total of 6280 di-nucleotides, 8139 tri-nucleotides, and 11,987 tetra-nucleotides with sufficient flanking region for primer design were screened with in silico mining. Ultimately, 18 tetra-nucleotide polymorphic loci were first identified and used to examine the genetic diversity in the Laojunshan population. The number of alleles per locus ranged from 5 to 13, observed and expected heterozygosity varied from 0.292 to 0.917 and 0.722 to 0.909, respectively. These results revealed that this endangered species' genetic diversity as not as low as expected. However, a heterozygote deficit was found in the Laojunshan population. We proposed that the management should focus on increasing the connectivity of remnant patches and fragments to increase the opportunity of greater gene flow among fragmented populations of A . rufipectus . This is the first time that polymorphic microsatellite markers were reported for A . rufipectus . These markers provide a valuable resource for future population genetics studies and for the management and conservation of this species. [ABSTRACT FROM AUTHOR]