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Aims: This study aimed to screen a bacterial strain with high detoxifying capability for aflatoxin B1 (AFB1), verify its biotransformation efficiency, and detoxification process., Methods and Results: A total of 350 samples collected from different environmental niche were screened using coumarin as the sole carbon source. High Performance Liquid Chromatography (HPLC) was used to detect residues of AFB1, and 16S rRNA sequencing was performed on the isolated strain with the highest AFB1 removal ratio for identification. The detoxified products of this strain were tested for toxicity in Escherichia coli as well as LO2, Caco-2, and HaCaT human cell lines. HPLC-MS was applied to further confirm the AFB1 removal and detoxification process., Conclusions: We identified a strain from plant leaf designated as DT with high AFB1-detoxifying ability that is highly homologous to Bacillus aryabhattai. The optimum detoxification conditions of this strain were 37°C and pH 8.0, resulting in 82.92% removal ratio of 2 μg mL-1 AFB1 in 72 h. The detoxified products were nontoxic for E. coli and significantly less toxic for the LO2, Caco-2, and HaCaT human cell lines. HPLC-MS analysis also confirmed the significant drop of the AFB1 characteristic peak. Two possible metabolic products, C19H15O8 (m/z 371) and C19H19O8 (m/z 375), were observed by mass spectrometry. Potential biotransformation pathway was based on the cleavage of double bond in the terminal furan of AFB1. These generated components had different chemical structures with AFB1, manifesting that the attenuation of AFB1 toxicity would be attributed to the destruction of lactone structure of AFB1 during the conversion process., (© The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International.)

Sighthounds, a distinctive group of hounds comprising numerous breeds, have their origins rooted in ancient artificial selection of dogs. In this study, we performed genome sequencing for 123 sighthounds, including one breed from Africa, six breeds from Europe, two breeds from Russia, and four breeds and 12 village dogs from the Middle East. We gathered public genome data of five sighthounds and 98 other dogs as well as 31 gray wolves to pinpoint the origin and genes influencing the morphology of the sighthound genome. Population genomic analysis suggested that sighthounds originated from native dogs independently and were comprehensively admixed among breeds, supporting the multiple origins hypothesis of sighthounds. An additional 67 published ancient wolf genomes were added for gene flow detection. Results showed dramatic admixture of ancient wolves in African sighthounds, even more than with modern wolves. Whole-genome scan analysis identified 17 positively selected genes (PSGs) in the African population, 27 PSGs in the European population, and 54 PSGs in the Middle Eastern population. None of the PSGs overlapped in the three populations. Pooled PSGs of the three populations were significantly enriched in "regulation of release of sequestered calcium ion into cytosol" (gene ontology: 0051279), which is related to blood circulation and heart contraction. In addition, ESR1, JAK2, ADRB1, PRKCE, and CAMK2D were under positive selection in all three selected groups. This suggests that different PSGs in the same pathway contributed to the similar phenotype of sighthounds. We identified an ESR1 mutation (chr1: g.42,177,149 T > C) in the transcription factor (TF) binding site of Stat5a and a JAK2 mutation (chr1: g.93,277,007 T > A) in the TF binding site of Sox5. Functional experiments confirmed that the ESR1 and JAK2 mutation reduced their expression. Our results provide new insights into the domestication history and genomic basis of sighthounds., (© The Author(s) 2023. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

Speciation plays a central role in evolutionary studies, and particularly how reproductive isolation (RI) evolves. The origins and persistence of RI are distinct processes that require separate evaluations. Treating them separately clarifies the drivers of speciation and then it is possible to link the processes to understand large-scale patterns of diversity. Recent genomic studies have focused predominantly on how species or RI originate. However, we know little about how species persist in face of gene flow. Here, we evaluate a contact zone of two closely related toad-headed lizards (Phrynocephalus) using a chromosome-level genome assembly and population genomics. To some extent, recent asymmetric introgression from Phrynocephalus putjatai to P. vlangalii reduces their genomic differences. However, their highly divergent regions (HDRs) have heterogeneous distributions across the genomes. Functional gene annotation indicates that many genes within HDRs are involved in reproduction and RI. Compared with allopatric populations, contact areas exhibit recent divergent selection on the HDRs and a lower population recombination rate. Taken together, this implies that divergent selection and low genetic recombination help maintain RI. This study provides insights into the genomic mechanisms that drive RI and two species persistence in the face of gene flow during the late stage of speciation., (© The Author(s) 2022. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

Context: The key gut microbial biomarkers for polycystic ovarian syndrome (PCOS) and how dysbiosis causes insulin resistance and PCOS remain unclear., Objective: To assess the characteristics of intestinal flora in PCOS and explore whether abnormal intestinal flora can affect insulin resistance and promote PCOS and whether chenodeoxycholic acid (CDCA) can activate intestinal farnesoid X receptor (FXR), improving glucose metabolism in PCOS., Setting and Design: The intestinal flora of treatment-naïve PCOS patients and hormonally healthy controls was analyzed. Phenotype analysis, intestinal flora analysis, and global metabolomic profiling of caecal contents were performed on a letrozole-induced PCOS mouse model; similar analyses were conducted after 35 days of antibiotic treatment on the PCOS mouse model, and glucose tolerance testing was performed on the PCOS mouse model after a 35-day CDCA treatment. Mice receiving fecal microbiota transplants from PCOS patients or healthy controls were evaluated after 10 weeks., Results: Bacteroides was significantly enriched in treatment-naïve PCOS patients. The enrichment in Bacteroides was reproduced in the PCOS mouse model. Gut microbiota removal ameliorated the PCOS phenotype and insulin resistance and increased relative FXR mRNA levels in the ileum and serum fibroblast growth factor 15 levels. PCOS stool-transplanted mice exhibited insulin resistance at 10 weeks but not PCOS. Treating the PCOS mouse model with CDCA improved glucose metabolism., Conclusions: Bacteroides is a key microbial biomarker in PCOS and shows diagnostic value. Gut dysbiosis can cause insulin resistance. FXR activation might play a beneficial rather than detrimental role in glucose metabolism in PCOS., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

Nigeria is an Afrotropical region with considerable ecological heterogeneity and levels of biotic endemism. Among its vertebrate fauna, reptiles have broad distributions, thus, they constitute a compelling system for assessing the impact of ecological variation and geographic isolation on species diversification. The red-headed rock agama, Agama agama , lives in a wide range of habitats and, thus, it may show genetic structuring and diversification. Herein, we tested the hypothesis that ecology affects its genetic structure and population divergence . Bayesian inference phylogenetic analysis of a mitochondrial DNA (mtDNA) gene recovered four well-supported matrilines with strong evidence of genetic structuring consistent with eco-geographic regions. Genetic differences among populations based on the mtDNA also correlated with geographic distance. The ecological niche model for the matrilines had a good fit and robust performance. Population divergence along the environmental axes was associated with climatic conditions, and temperature ranked highest among all environmental variables for forest specialists, while precipitation ranked highest for the forest/derived savanna, and savanna specialists. Our results cannot reject the hypothesis that niche conservatism promotes geographic isolation of the western populations of Nigerian A. agama . Thus, ecological gradients and geographic isolation impact the genetic structure and population divergence of the lizards . This species might be facing threats due to recent habitat fragmentation, especially in western Nigeria. Conservation actions appear necessary., (© The Author(s) (2019). Published by Oxford University Press on behalf of Editorial Office, Current Zoology.)

Salinization is one of the most critical abiotic stress factors for crops and a rising setback in agro-ecosystems. Changes in weather, land usage, and the salinization of irrigation water are increasing soil salinity of many farmlands. Increased soil salinity alters the plant quality, which subsequently may trigger bottom-up effects on herbivorous insect. We examined the bottom-up effect of salinity stress on population parameters of the brown planthopper (BPH), Nilaparvata lugens through rice (Oryza sativa L.) plant. The results revealed that salinity interfered with egg hatching of BPH. The nymphal development period, adult longevity, and oviposition were also influenced by salinity. Notable differences appeared in the intrinsic growth rate (r), the finite increase rate (λ) and the net reproduction rate (R0) of BPH, and a concentration-dependent effect was detected. Although salinity adversely affected BPH development, population projection predicted a successful growth of the BPH population in a relatively short time under the treatment of low and medium levels of salinity (6, 8, and 10 dS/m of NaCl), whereas higher salt concentrations (12 and 14 dS/m) lead to significant fitness costs in BPH populations. Our study predicts that BPH could become a problem in areas with lower and medium salinity and that those planthoppers may exacerbate the negative effects of salinity for rice production. This study will provide valuable information for understanding the field abundance and distribution of BPH on saline rice field, thus contributing to the development of eco-friendly strategies to manage this pest in saline ecosystems., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Planthoppers (Nilaparvata lugens, Sogatella furcifera, and Laodelphax striatellus) (Hemiptera: Delphacidae) are the most important pests affecting rice production. Pesticide spraying for its control may cause harmful effects on human health and the environment, especially the loss of biodiversity. The consequences of these changes on biodiversity and ecological services are well studied in tropical irrigated paddy fields, but are largely unknown in subtropical areas. Organic regime provides an environment-friendly method for biodiversity conservation; however, it is unclear whether this regime can suppress planthopper populations effectively in paddy fields. Consequently, we compared species richness, abundance, community structure, and evenness of natural enemies and planthoppers between organic and conventional rice fields (n = 35) distributed across four sites in China. The results showed that species richness was higher in organic fields than in conventional fields. Shannon index and evenness of predators and parasitoids were higher in most of the organic fields than their conventional counterparts. Furthermore, planthopper density showed a significant negative relationship with increased richness and evenness for both predators and parasitoids. These results underscore the notion that management regimes influence biodiversity in rice field. Most importantly, this has direct implications on the efficacy of natural pest control services rendered by predators and parasitoids associated with planthoppers in China and potentially other rice production regions in Asia., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Most living organisms developed the innate clock system to anticipate daily environmental changes and to enhance their chances of survival. timeless (tim) is a canonical clock gene. It has been extensively studied in Drosophila melanogaster (Diptera: Drosophilidae) as a key component of the endogenous circadian clock, but its role is largely unknown in some agriculture pests. Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae), an important rice pest, exhibits a robust locomotor rhythm. In the present study, we cloned tim gene (ls-tim) from L. striatellus and investigated its function in the regulation of behavioral rhythms. Quantitative real-time polymerase chain reaction revealed a circadian expression pattern of ls-tim under different light conditions with a trough in the photophase and a peak in the late scotophase. After the knockdown of ls-tim via RNA interference (RNAi), the adults showed an earlier onset of locomotor activity under light/dark cycles and became arrhythmic in constant darkness. ls-tim RNAi also abolished the timing of adult emergence that normally occurs in the early photophase. These results suggest that ls-tim is essential for the light-entrained circadian rhythms in L. striatellus and provide more insights into the endogenous clock network underlying the behavioral and physiological rhythms of this insect.

Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae) is an important predatory natural enemy of planthopper and leafhopper eggs in Asian rice paddy fields. Cyrtorhinus lividipennis is known to rely largely on herbivore-induced plant volatiles to identify eggs embedded in rice stem tissues for feeding and on pheromones for mating. However, exactly how C. lividipennis decode these chemical information is unclear. In most insects, the odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) are essential for seeking out food resources and mates. In this study, we identified 10 OBP and 5 CSP genes in C. lividipennis and investigated their expression patterns in various tissues of adult males and females by quantitative real-time PCR (qRT-PCR). Six OBP genes (ClivOBP1, 2, 4, 6, 9, and 10) were mainly expressed in the male antennae, whereas three genes (ClivOBP3, ClivOBP7, and ClivOBP8) had high expression in the female antennae. ClivCSP1 was predominantly expressed in the male antennae. These findings suggest that most ClivOBPs and ClivCSPs are likely involved in food-searching behavior. The recognition of the pheromone molecules provides the basis for further functional studies on the chemoreception system of C. lividipennis., (© The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Validamycin A (Val-A) synthesized by Streptomyces hygroscopicus 5008 is widely used as a high-efficient antibiotic to protect plants from sheath blight disease. A novel fermentation strategy was introduced to stimulate Val-A production by adding oxygen carriers. About 58 % increase in Val-A production was achieved using liquid paraffin. Further, biomass, carbon source, metabolic genes, and metabolic enzymes were studied. It was also found that the supplementation of liquid paraffin increased the medium dissolved oxygen and intracellular oxidative stress level. The expression of the global regulators afsR and soxR sensitive to ROS, ugp catalyzing synthesis of Val-A precursor, and Val-A structural genes was enhanced. The change of the activities of glucose-6-phosphate dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase was observed, which reflected the redirection of carbon metabolic flux. Based on these results, liquid paraffin addition as an oxygen carrier could be a useful technique in industrial production of Val-A and our study revealed a redox-based secondary metabolic regulation in S. hygroscopicus 5008, which provided a new insight into the regulation of the biosynthesis of secondary metabolites.

The rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), is a serious pest species both in its original distribution region of northern America and its invaded regions of eastern Asia and southern Europe. The odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) play important roles in host and mate locating, thus might play a significant role in the success of the species as an invader, which has not been characterized yet. We identified 10 OBPs and 5 CSPs in L. oryzophilus and investigated the expression profiles of these genes in various tissues by quantitative real-time PCR. Five classic OBPs were predominantly expressed in the antennae. CSPs were expressed ubiquitously with particularly high transcript levels in antennae, legs, and wings. Three antenna-specific OBPs (LoOBP1, 8, 11) were up-regulated following 1-3 d of food deprivation and down-regulated afterward. These findings suggest most classic OBPs are likely involved in chemoreception whereas CSPs as well as the minus-C OBPs may have broader physiological functions, which in turn may help to understand the molecular aspects of chemical communication in this invasive insect., (© The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

True frogs of the genus Rana are widely used as model organisms in studies of development, genetics, physiology, ecology, behavior, and evolution. Comparative studies among the more than 100 species of Rana rely on an understanding of the evolutionary history and patterns of diversification of the group. We estimate a well-resolved, time-calibrated phylogeny from sequences of six nuclear and three mitochondrial loci sampled from most species of Rana, and use that phylogeny to clarify the group's diversification and global biogeography. Our analyses consistently support an "Out of Asia" pattern with two independent dispersals of Rana from East Asia to North America via Beringian land bridges. The more species-rich lineage of New World Rana appears to have experienced a rapid radiation following its colonization of the New World, especially with its expansion into montane and tropical areas of Mexico, Central America, and South America. In contrast, Old World Rana exhibit different trajectories of diversification; diversification in the Old World began very slowly and later underwent a distinct increase in speciation rate around 29-18 Ma. Net diversification is associated with environmental changes and especially intensive tectonic movements along the Asian margin from the Oligocene to early Miocene. Our phylogeny further suggests that previous classifications were misled by morphological homoplasy and plesiomorphic color patterns, as well as a reliance primarily on mitochondrial genes. We provide a phylogenetic taxonomy based on analyses of multiple nuclear and mitochondrial gene loci. [Amphibians; biogeography; diversification rate; Holarctic; transcontinental dispersal., (© The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Our previous study demonstrated the involvement of cystic fibrosis transmembrane conductance regulator (CFTR) in transporting bicarbonate that is necessary for sperm capacitation; however, whether its involvement is direct or indirect remains unclear. The present study investigated the possibility of a Cl-/HCO3- exchanger (solute carrier family 26, number 3 [SLC26A3]) operating with CFTR during guinea pig sperm capacitation. Incubating sperm in media with various concentrations of Cl- resulted in varied percentages of capacitated sperm in a concentration-dependent manner. Depletion of Cl-, even in the presence of HCO3-, abolished sperm capacitation and vice versa, indicating the involvement of both anions in the process. Capacitation-associated HCO3--dependent events, including increased intracellular pH, cAMP production, and protein tyrosine phosphorylation, also depend on Cl- concentrations. Similar Cl- dependence and inhibitor sensitivity were observed for sperm-hyperactivated motility and for sperm-egg fusion. The expression and localization of CFTR and SLC26A3 were demonstrated using immunostaining and Western blot analysis. Taken together, our results indicate that Cl- is required for the entry of HCO3- that is necessary for sperm capacitation, implicating the involvement of SLC26A3 in transporting HCO3-, with CFTR providing the recycling pathway for Cl-.

Aims: To isolate an antagonist for use in the biological control of the phytopathogenic fungus Penicillium expansum and purify the antifungal component produced by the antagonist., Methods and Results: An antifungal strain HT16 was isolated from locusts, showing strong inhibition to Pen. expansum. Based on its in vitro effectiveness, HT16 was characterized as a strain of Paenibacillus polymyxa by phenotypic tests and 16S rDNA sequence analysis. It was found that the antifungal component HT16 secreted was only induced by Poria cocos sclerotium (PCS), and it remained active after sterilization at 121 degrees C for 15 min. The protein was purified by ammonium sulfate precipitation, heating process, and ultrafiltration using a 10 kDa cut-off membrane. The molecular weight of the purified antifungal protein, which was determined by mass spectrometry, was 4517 Da., Conclusions: A novel bacterial strain HT16 antagonistic to Pen. expansum was isolated from locusts and identified as Pae. polymyxa. The antifungal protein of 4517 Da was purified, and its production needed the inducer PCS in the fermentation medium., Significance and Impact of the Study: The antagonistic protein from Pae. polymyxa showed strong antifungal activity against phytopathogenic fungus Pen. expansum. This strain HT16 and the antifungal metabolite are therefore strong candidates for the biocontrol of phytopathogens in agriculture.