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BACKGROUND: Ticks are disease vectors that are a matter of worldwide concern. Antibiotic treatments have been used to explore the interactions between ticks and their symbiotic microorganisms. In addition to altering the host microbial community, antibiotics can have toxic effects on the host. RESULTS: In the tick Haemaphysalis longicornis, engorged females showed reproductive disruption after microinjection of tetracycline. Multi‐omics approaches were implemented to unravel the mechanisms of tick reproductive inhibition in this study. There were no significant changes in bacterial density in the whole ticks on Day (D)2 or D4 after tetracycline treatment, whereas the bacterial microbial community was significantly altered, especially on D4. The relative abundances of the bacteria Staphylococcus, Bacillus and Pseudomonas decreased after tetracycline treatment, whereas the relative abundances of Coxiella and Rhodococcus increased. Ovarian transcriptional analysis revealed a cumulative effect of tetracycline treatment, as there was a significant increase in the number of differentially expressed genes with treatment time and a higher number of downregulated genes. The tick physiological pathways including lysosome, extracellular matrix (ECM)–receptor interaction, biosynthesis of ubiquinone and other terpenoids‐quinones, insect hormone biosynthesis, and focal adhesion were significantly inhibited after 4 days of tetracycline treatment. Metabolite levels were altered after tetracycline treatment and the differences increased with treatment time. The differential metabolites were involved in a variety of physiological pathways; the downregulated metabolites were significantly enriched in the nicotinate and nicotinamide metabolism, galactose metabolism, and ether lipid metabolism pathways. CONCLUSIONS: These findings indicate that tetracycline inhibits tick reproduction through the regulation of tick bacterial communities, gene expression and metabolic levels. The results may provide new strategies for tick control. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Hand gesture plays an important role in many circumstances, which is one of the most common interactive methods in daily life, especially for disabled people. Human–machine interaction is another popular research topic to realize direct and efficient control, making machines intelligent and maneuverable. Here, a special human–machine interaction system is proposed and namedas computer‐vision (CV) based gesture‐metasurface interaction (GMI) system, which can be used for both direct beam manipulations and real‐time wireless communications. The GMI system first needs to select its working mode according to the gesture command to determine whether to perform beam manipulations or wireless communications, and then validate the permission for further operation by recognizing unlocking gesture to ensure security. Both beam manipulation and wireless communication functions are validated experimentally, which show that the GMI system can not only realize real‐time switching and remote control of different beams through gesture command, but also communicate with a remote computer in real time by translating the gesture language to text message. The proposed non‐contact GMI system has the advantages of good interactivity, high flexibility, and multiple functions, which can find potential applications in community security, gesture‐command smart home, barrier‐free communications, and so on. [ABSTRACT FROM AUTHOR]

The extensive utilization of antibiotics in the field of animal husbandry gives rise to various concerns pertaining to the environment and human health. Here, we demonstrate that the administration of tetracycline impedes blood meal digestion in the tick Haemaphysalis longicornis. Tissue sectioning, 16S rRNA high-throughput sequencing, and transcriptome sequencing of the midgut were employed to elucidate the mechanism underlying tetracycline toxicity. The treatment group consisted of engorged female ticks that were subjected to tetracycline microinjections (75 µg per tick), whereas the control group received sterile water injections. On days 2 and 4 following the injections, the tick body weight changes were assessed and the midguts were dissected and processed. Change in tick body weight in tetracycline-treated group was less than in the control group. In tetracycline-treated ticks, midgut epithelial cells were loosely connected and blood meal digestion was impaired compared to the control group. There was no significant change in midgut bacterial diversity after tetracycline treatment. On day 2 following treatment, the relative abundance of Escherichia-Shigella was significantly decreased, whereas the relative abundance of Allorhizobium was significantly increased compared to the control group. On day 4 following treatment, the relative abundance of Escherichia-Shigella, Allorhizobium, Ochrobactrum, and Acidibacter decreased significantly, whereas the relative abundance of Paraburkholderia and Pelomonas increased significantly. Tetracycline treatment also affected midgut gene expression, producing a cumulative effect wherein the differentially expressed genes (DEGs) were mostly down-regulated. KEGG enrichment pathway analysis revealed that on day 2 the up-regulated DEGs were significantly enriched in 21 pathways, including apoptosis and phagosome. Comparatively, the down-regulated DEGs were significantly enriched in 26 pathways, including N-glycan biosynthesis, lysosome, and autophagy. In contrast, on day 4 the up-regulated DEGs were significantly enriched in 10 pathways including aminoacyl-tRNA biosynthesis, ribosome biogenesis, RNA transport, and DNA replication, whereas the down-regulated differential genes were significantly enriched in 11 pathways including lysosome, peroxisome, N-glycan biosynthesis, and fatty acid synthesis. This indicates that tetracycline injection inhibited blood meal digestion by affecting midgut digestive cells, gut flora diversity, and gene expression. These findings could contribute to tick control by inhibiting blood meal digestion. [ABSTRACT FROM AUTHOR]

In this paper, we showed an example of acid-directed hydrothermal synthesis of three Cd-based metal–organic frameworks (MOFs) under similar conditions, namely, [Cd(TIDB)(AA)0.5(NO3)]n (1), [Cd3(TIDB)2(AA)2(H2O)2(HCOO)2]n (2), and {[Cd4(TIDB)(AA)4(H2O)5](C2H5OH)2(H2O)2}n (3) (TIDB = 1,3,5-tri(1H-imidazol-1-yl)benzene, H2AA = anthracene-9,10-dicarboxylic acid). Compound 1 was synthesized by the introduction of HNO3 as a structure-directing agent. It has 2D coordination networks with the 3,4-c bey topology. The porous 3D supramolecular framework in compound 1 is stabilized by H-bonds. Compound 2 was formed with the use of a HCOOH agent. It has a 3D coordination network with a new 3,4,5-c underlying net topology, and it is also porous. Compound 3 was obtained using a CH3COOH agent. It has a disordered non-porous 3D coordination network. Because 3 was hard to purify, 1 and 2 were chosen for further property investigation. On the one hand, fluorescence studies showed that 1 and 2 are both blue-emitting MOFs with quantum yields of 2.3% and 0.8%, respectively. On the other hand, CO2 cycloaddition performance was also tested, which revealed that 2 has a superior catalytic conversion of epoxybutane at 60 °C and 1 atm with a high yield of up to 95.6%. [ABSTRACT FROM AUTHOR]

Polarization plays an important role in practical applications, and hence it is an essential task to generate the desired polarization of a spatial propagating wave (SPW). Here, the authors propose a method to design radiation metasurface, or metasurface emitter, which can produce arbitrarily polarized SPW. Different from the conventional transmission and reflection metasurfaces that can only manipulate the incoming spatial wave, the proposed radiation metasurface can be regarded as an electromagnetic (EM) wave emitter that can generate SPW by itself. More importantly, the polarization of the generated SPW can be flexibly customized by designing the phase distribution on metasurface. The metasurface is fed by a monopole antenna, and the energy is first coupled into the metasurface to form a surface wave. Modulated by the metasurface, the surface wave is then converted into SPW. As a proof of concept, they design and fabricate the radiation metasurfaces that are capable of generating radially, azimuthally, linearly, and circularly polarized SPWs, as well as dual‐beam radiations with different polarizations, respectively. The measured results have a good match to the theoretical predictions and full‐wave simulations. The proposed method provides an efficient way to generate SPWs with any desired polarizations for easy integration. [ABSTRACT FROM AUTHOR]

Ticks have a diversity of habitats and host blood meals. Whether and how factors such as tick developmental stages, habitats and host blood meals affect tick bacterial microbiota is poorly elucidated. In the present study, we investigated the bacterial microbiotas of the hard tick Haemaphysalis longicornis, their blood meals and habitats using 16S rRNA gene high-throughput sequencing. The bacterial richness and diversity in ticks varied depending on the tick developmental stage and feeding status. Results showed that fed ticks present a higher bacterial richness suggesting that ticks may acquire bacteria from blood meals. The significant overlap of the bacteria of fed ticks and the host blood also supports this possibility. Another possibility is that blood meals can stimulate the proliferation of certain bacteria. However, most shared bacteria cannot transmit throughout the tick life cycle, as they were not present in tick eggs. The most shared bacteria between ticks and habitats are members of the genera Staphylococcus, Pseudomonas, Enterobacter, Acinetobacter and Stenotrophomonas, suggesting that these environmental bacteria cannot be completely washed away and can be acquired by ticks. The predominant proportion of Coxiella in fed females further demonstrates that this genus is involved in H. longicornis physiology, such as feeding activity and nutritional provision. These findings further reveal that the bacterial composition of ticks is influenced by a variety of factors and will help in subsequent studies of the function of these bacteria. [ABSTRACT FROM AUTHOR]

The ornate sheep tick, Dermacentor marginatus, is widespread in Europe. Its vector role of various zoonotic pathogens received much attention in these regions. However, the genomic resources of the ticks are limited. In this study, the complete mitochondrial genome of a single female D. marginatus collected in Slovakia was sequenced through the Illumina HiSeq sequencing platform. The mitochondrial genome is 15,067 bp long and contains 13 protein-coding genes, two ribosomal RNA genes and 22 transfer RNA genes. The overall G+C content is 21.6%. The gene order is identical to that of Metastriata ticks. The codon usage pattern is similar with that of other tick species. As in other ticks, two truncated tRNA genes were observed. Two control regions were found between tRNA-Leu and tRNA-Cys, tRNA-Ile and rrnS, respectively. The mitochondrial genome contains three noncoding regions, which is similar to that in D. nitens. The noncoding region located between rrnS and tRNA-Val is shorter than that of other Dermacentor species. Phylogenetic analyses indicate that D. marginatus is clustered with other Dermacentor species. These findings are helpful for exploring the systematics and evolution of ticks in the future. [ABSTRACT FROM AUTHOR]

Ticks are exclusive blood-feeding parasites that are of medical and veterinary importance. Ticks are also host for several maternally inherited symbiotic bacteria that are non-pathogenic bacteria and have potential roles in tick biology and the transmission of co-infecting pathogens. In order to gain a comprehensive view of these symbionts in ticks, we overviewed their incidence and biological importance within ticks based on available data. The symbionts in ticks are diverse, and their incidence and frequency vary across different tick species and different geographical populations of the same species. In some cases, symbionts of Coxiella, Francisella and Rickettsia genera may provide tick hosts essential nutrients absent from the exclusive food source of ticks and exhibit mutualistic relationships with their hosts. However, most symbionts are facultative and affect the biological phenotypes of their tick hosts through various ways. For some strains of Coxiella and Francisella, advanced genomic data and phylogenetic investigations have revealed their interactions with hosts and their evolutionary transitions of pathogenic and mutualistic forms. These findings are valuable for understanding tick-symbiont associations, and may help to develop new strategies to control ticks and tick-borne diseases. [ABSTRACT FROM AUTHOR]

Ticks are obligate blood-sucking arthropods, which can feed on mammals, birds, reptiles and amphibians. Ticks are reservoirs for various pathogens which they transmit to both humans and animals. The tick-borne diseases induced by these pathogens are not only harmful to human and animal health, but also cause significant economic losses to livestock farmers. Research on ticks is, therefore, both medically and economically important. This paper reviews previous research on the diversity of tick-borne pathogens, tick-pathogen-host interaction mechanisms, tick-borne disease prevention and control, tick symbiont diversity, function and the mechanisms underlying tick-symbiont interactions. An increase in the amount of research on ticks and technological advances has resulted in an obvious improvement in the quality of research and information available on these pests. These results can not only reveal more of the biology of ticks, but also help the prevention and control of tick-borne diseases. [ABSTRACT FROM AUTHOR]

Abstract: Double infections of Wolbachia and Spiroplasma are frequent in natural populations of Tetranychus truncatus, a polyphagous mite species that has been a dominant species in China since 2009. However, little is known about the causes and ecological importance of such coexistences. In this study, we established T. truncatus strains with different infection types and then inferred the impact of the two endosymbionts on host reproduction and fitness. Double infection induced cytoplasmic incompatibility, which was demonstrated by reduction in egg hatchability of incompatible crosses. However, doubly infected females produced more eggs relative to other strains. Wolbachia and Spiroplasma did not affect host survival, whereas doubly infected females and males developed faster than other strains. Such reproduction and fitness benefits provided by double infections may be associated with the lower densities of each symbiont, and the quantitative results also confirmed competition between Wolbachia and Spiroplasma in doubly infected females. These symbiont‐conferred beneficial effects maintain stable prevalence of the symbionts and also help drive T. truncatus outbreaks in combination with other environmental factors. [ABSTRACT FROM AUTHOR]

Many species of mites are of agricultural and veterinary importance to human. The bacterial symbiont Cardinium is assumed to be widespread and involved in manipulating its mite host's reproduction. We investigated Cardinium infections in phylogenetically diverse mite species based on published data. Cardinium was reported in 45 mite species, representing 3 orders and 14 families. Some Cardinium strains can influence their mite hosts' reproduction via two strategies: cytoplasmic incompatibility and feminization. The phylogeny of the examined mites was well resolved based on the 18S rRNA gene, whereas Cardinium phylogeny was not completely concordant with its associated host phylogeny, raising the possibility that horizontal transmission of Cardinium has occurred among species. In addition, Cardinium phylogeny was associated with the ecology of the hosts. Cardinium cooperating with other endosymbionts influences the ecology and evolution of its host. [ABSTRACT FROM AUTHOR]

DNA methylation is an epigenetic mechanism for regulating developmental and other important processes in eukaryotes. Several essential components of the DNA methylation machinery have been identified, such as DNA methyltransferases. In the two-spotted spider mite, Tetranychus urticae Koch, we have identified one DNA methyltransferase 3 gene ( Tudnmt3) and tentatively investigated its potential role in adult females and males. Here, to better elucidate the functional role of Tudnmt3, its protein structure, expression and localization were subjected to more detailed analyses. Bioinformatic analyses clearly showed that the structure of TuDNMT3 was highly conserved, with several vital amino acid residues for the activation and stabilization of its confirmation. Western blot analyses revealed that this protein was expressed in both genders, with higher expression in adult females, which was inconsistent with the gene expression, suggesting translational regulation of Tudnmt3. Subsequent immunodetection provided supportive evidence for higher expression of the TuDNMT3 protein in adult females and indicated that this protein was generally localized in the cytoplasm and that its expression was predominantly confined to the genital region of spider mites, strengthening the hypothesis that de novo methylation mediated by Tudnmt3 in gonad development or gametogenesis has a different mechanism from maintenance methyltransferase. [ABSTRACT FROM AUTHOR]

Wolbachia are endosymbiotic bacteria that are widely distributed in arthropods. The bacteria cause reproductive disorders and affect fitness-related traits of their hosts. The generalist predatory mite Neoseiulus cucumeris(Oudemans) (Acari: Phytoseiidae) is a cosmopolitan species commonly used as a biological control agent for mites. Here we investigated the effect of Wolbachia infection in the prey, Tetranychus urticae, on predation by N. cucumeris by using both functional response tests (effect of prey egg density on predation) and choice and no-choice tests. The rate of egg consumption decreased with increasing egg density for both infected and uninfected eggs (Type II responses). In a no-choice test, N. cucumeris consumed approximately equal numbers of infected and uninfected eggs, nymphs and adults but consumed fewer infected larvae than uninfected larvae. In the first choice test, different developmental stages of T. urticae were provided, N. cucumeris preferred eggs and larvae over nymphs and adults. Furthermore, to determine how pre-infestation, developmental stages of prey and bacterial infection affect the choice of N. cucumeris, the second choice test was performed. N. cucumeris preferred pre-infested leaf discs over leaf discs that had not been infested, and had a significant preference for uninfected prey, regardless of the presence of plant tissue. These results suggest that N. cucumeris is first attracted by volatiles emitted by attacked plants and then select their preferred prey. [ABSTRACT FROM AUTHOR]

Wolbachia are maternally inherited intracellular bacteria that infect a wide range of arthropods and cause an array of effects on host reproduction, fitness and mating behavior. Although our understanding of the Wolbachia-associated effects on hosts is rapidly expanding, our knowledge of the host factors that mediate Wolbachia dynamics is rudimentary. Here, we explore the interactions between Wolbachia and its host, the two-spotted spider mite Tetranychus urticae Koch. Our results indicate that Wolbachia induces strong cytoplasmic incompatibility (CI), increases host fecundity, but has no effects on the longevity of females and the mating competitiveness of males in T. urticae. Most importantly, host mating pattern was found to affect Wolbachia density dynamics during host aging. Mating of an uninfected mite of either sex with an infected mite attenuates the Wolbachia density in the infected mite. According to the results of Wolbachia localization, this finding may be associated with the tropism of Wolbachia for the reproductive tissue in adult spider mites. Our findings describe a new interaction between Wolbachia and their hosts. [ABSTRACT FROM AUTHOR]

Wolbachia are endosymbiotic bacteria that commonly infect arthropods and cause reproductive disorders in host. Within several Tetranychus species, Wolbachia have been detected and shown to affect their reproduction. However, little is known about their transmission and distribution patterns in natural populations of Tetranychus species. Here, we used multilocus sequence typing to confirm Wolbachia infection status and examined the relationship between Wolbachia infection status and host phylogeny, mitochondrial diversity, and geographical range in five Tetranychus species ( Tetranychus truncatus, Tetranychus urticae, Tetranychus pueraricola, Tetranychus phaselus, and Tetranychus kanzawai) from 21 populations in China. The prevalence of Wolbachia within the five Tetranychus species ranged from 31.4 to 100 %, and the strains were remarkably diverse. Together, these observations indicate that Wolbachia was introduced to these populations on multiple separate occasions. As in other arthropods, the same Tetranychus species can accommodate very different strains, and identical Wolbachia occasionally infect different species. These observations suggest that Wolbachia are transmitted both vertically and horizontally. Horizontally, transmission is probably mediated by the host plants. The distribution patterns of Wolbachia were quite different among populations of the same species, suggesting that the dynamics of Wolbachia in nature may be affected by ecological and other factors. [ABSTRACT FROM AUTHOR]

Wolbachia and Cardinium are maternally inherited intracellular bacteria that can manipulate the reproduction of their arthropod hosts, such as by inducing cytoplasmic incompatibility (CI). Although the reproductive alteration induced by Wolbachia or Cardinium have been well investigated, the effects of these two endosymbionts co-infecting the same host are poorly understood. We found that Tetranychus piercei McGregor is naturally infected with Wolbachia and Cardinium. We performed all possible crossing combinations using naturally infected and cured strains, and the results show that Wolbachia induced a weak level of CI, while Cardinium-infected and doubly infected males caused severe CI. Wolbachia and Cardinium could not rescue CI each other; however, Wolbachia boosted the expression of Cardinium-induced CI. Quantitative PCR results demonstrated that CI was associated with the infection density of Wolbachia and Cardinium. [ABSTRACT FROM AUTHOR]

Background: The important roles of microbial flora in tick biology and ecology have received much attention. Dermacentor marginatus and Dermacentor reticulatus are known vectors of various pathogens across Europe, including Slovakia. However, their bacterial microbiomes are poorly explored. Methods: In this study, bacterial microbiomes of field-collected D. marginatus and D. reticulatus from Slovakia were characterized using 16S rRNA high-throughput sequencing. Results: Different analyses demonstrated that the D. marginatus and D. reticulatus microbiomes differ in their diversity and taxonomic structures. Furthermore, species- and sex-specific bacteria were detected in the two species. A possible bacterial pathogen "Candidatus Rhabdochlamydia sp." was detected from D. marginatus males. Among the observed bacteria, Rickettsia showed high abundance in the two species. Several maternally inherited bacteria such as Coxiella, Arsenophonus, Spiroplasma, Francisella and Rickettsiella, were abundant, and their relative abundance varied depending on tick species and sex, suggesting their biological roles in the two species. Conclusions: The bacterial microbiomes of field-collected D. marginatus and D. reticulatus were shaped by tick phylogeny and sex. Maternally inherited bacteria were abundant in the two species. These findings are valuable for understanding tick-bacteria interactions, biology and vector competence of ticks. [ABSTRACT FROM AUTHOR]

Understanding dispersal ability in pest species is critical for both theoretical aspects of evolutionary and population biology and from a practical standpoint, such as implementing effective forecasting systems. The small brown planthopper (SBPH), Laodelphax striatellus (Fallén), is an economically important pest, but few data exist on its dispersal ability. Here, we used mitochondrial and nuclear markers to elucidate the population genetic structure of SBPH and of the parasitic bacterium Wolbachia throughout temperate and subtropical China. Our results showed that the SBPH populations in China lack significant differences in genetic structure, suggesting extensive gene flow. Multilocus sequence typing revealed that Wolbachia infection was systematic and due to the same strain (wStri) within and across populations. However, the mtDNA haplogroups had a nonrandom distribution across the sampling localities, which correlated to latitudinal and climatic gradients. We explain this mito-nuclear discordance as a result of historical population recolonization or mitochondria adaptation to climate. [ABSTRACT FROM AUTHOR]