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Abstract The extensive mining of bastnasite (CeFCO3) has caused severe pollution of lanthanum (La), cerium (Ce), and fluorine (F) in the surrounding farmland soil, threatening the safety of the soil-plant system. However, the stress effects of the interaction among these three elements on the tolerance and accumulation traits of Brassica chinensis L. (B. chinensis) are unclear. In this study, the interaction mechanisms of these three pollutants regulating the growth characteristics, antioxidant capacity, and accumulation characteristics of B. chinensis was explored using pot experiments of La-Ce (LC), Ce-F (CF), La-F (LF), and La-Ce-F (LCF) interactions. The LC interaction pollution treatments at the element concentrations higher than those of LC3 showed significant impact (P Ce-F > La-Ce-F > La-Ce, which was supported by the integrated biomarker response (IBR) analysis. The synergistic effect of La and Ce in La-Ce experiment promoted these two elements in the plants, whereas the presence of F in CF, LF, and LCF combined pollution treatments inhibited the absorption of La and Ce. Moreover, under the interaction among three elements, the synergistic effect of La and Ce in LC treatment enhanced the biotranslocation factor (BTF) of both elements, reaching the highest levels of 0.36 and 0.40, respectively. The addition of F in CF (BTF of 0.3 and 0.15, respectively), LF (BTF of 0.25 and 0.15, respectively), and LCF (BTF of 0.21, 0.24, and 0.15, respectively) treatments reduced the BTF of La and Ce in the plants due to the formation of insoluble precipitates between F with La or Ce. In conclusion, the interaction between La and Ce could reduce the tolerance of B. chinensis, while the presence of F could enhance the plant resistance to both La and Ce.

Abstract The extensive mining of bastnasite (CeFCO3) has caused pollution of lanthanum (La), cerium (Ce), and fuorine (F) in the surrounding farmland soil, severely threatening the safety of the soil ecosystem. However, the interaction effects of various chemical fractions of La, Ce, and F on the composition of microbial communities are unclear. In our study, high-throughput sequencing was performed based on the pot experiments of four types of combined pollution soils, i.e., La + Ce (LC), Ce + F (CF), La + F (LF), and La + Ce + F (LCF), and the pollution concentration ranges of these three elements of 20–240, 40–450, and 150–900 mg kg–1, respectively. The improved Tessier method was used to investigate the interaction effects of chemical fractions of these elements on the variations in the soil microbial compositions. The result showed the residual form of La (La_RES) displayed restraint on Abditibacteriota, leading to its undetected level in the highest concentration of LC-polluted soils, whereas promoted relative abundance of microbes (Planctomycetota, Elusimicrobiota, Gemmatimonadota, and Rozellomycota) by more than 80%; the exchangeable and organic-bound forms of Ce and F as well as the iron-manganese-bound and residual forms of F were identified as the stress factors for the sensitive bacteria (e.g., WS4, Elusimicrobiota, RCP2-54, and Monoblepharomycota) in CF-polluted soils; in LF-polluted soils, the water-soluble form of La showed the most toxic effect on RCP2-54, Nitrospirota, and FCPU426, leading to decreased relative abundance by more than 80%; while La_RES and iron-manganese-bound form of F were identified as the stress factors for the relative abundance of Nitrospirota, Elusimicrobiota, and GAL15, showing decline of more than 80% in LCF-polluted soils. Our study revealed both inhibition and promotion effects of the element interaction on the growth of microbial communities, providing a certain experimental evidence to support further exploration of the treatment of environmental pollution caused by these elements.

Ophiocordyceps sinensis (Berk.) is an entomopathogenic fungus that can infect the larva of the ghost moth, Hepialus xiaojinensis, causing mummification after more than one year. This prolonged infection provides a valuable model for studying the immunological interplay between an insect host and a pathogenic fungus. A comparative transcriptome analysis of pre-infection (L) and one-year post-infection (IL) larvae was performed to investigate the immune response in the host. Here, a total of 59,668 unigenes were obtained using Illumina Sequencing in IL and L. Among the 345 identified immune-related genes, 83 out of 86 immune-related differentially expressed genes (DEGs) had a much higher expression in IL than in L. Furthermore, the immune-related DEGs were classified as pathogen recognition receptors (PRRs), signal modulators or transductors, and immune effector molecules. Serpins and protease inhibitors were found to be upregulated in the late phase of infection, suppressing the host’s immune response. Based on the above analysis, the expression levels of most immune-related genes would return to the baseline with the immune response being repressed in the late phase of infection, leading to the fungal immunological tolerance after prolonged infection. Meanwhile, the transcriptomes of IL and the mummified larva (ML) were compared to explore O. sinensis invasion. A total of 1408 novel genes were identified, with 162 of them annotated with putative functions. The gene families likely implicated in O. sinensis pathogenicity have been identified, primarily including serine carboxypeptidase, peroxidase, metalloprotease peptidase, aminopeptidases, cytochrome P450, and oxidoreductase. Furthermore, quantitative real-time PCR (qPCR) was used to assess the expression levels of some critical genes that were involved in immune response and fungal pathogenicity. The results showed that their expression levels were consistent with the transcriptomes. Taken together, our findings offered a comprehensive and precise transcriptome study to understand the immune defense in H. xiaojinensis and O. sinensis invasion, which would accelerate the large-scale artificial cultivation of this medicinal fungus.

Dental caries is now considered to be caused by acids produced by the overall dental plaque microbiota rather than by specific pathogens. This study focused on the relationship between dental caries experience and the variations in tongue microbiota, which is adjacent but separate from the dental plaque microbiota.

Abstract Background There is little information regarding the duck enteritis virus (DEV) US10 gene and its molecular characterization. Methods Duck enteritis virus US10 was amplified and cloned into the recombinant vector pET32a(+). The recombinant US10 protein was expressed in Escherichia coli BL21 cells and used to immunize rabbits for the preparation of polyclonal antibodies. The harvested rabbit antiserum against DEV US10 was detected and analyzed by agar immunodiffusion. Using this antibody, western blotting and indirect immunofluorescence analysis were used to analyze the expression level and subcellular localization of US10 in infected cells at different time points. Quantitative reverse-transcription PCR (qRT-PCR) and pharmacological inhibition tests were used to ascertain the kinetic class of the US10 gene. A mass spectrometry-based strategy was used to identify US10 in purified DEV virions and quantify its abundance. Results The recombinant pET32a(+)/US10 protein was expressed as inclusion bodies, purified by gradient urea washing, and used to prepare specific antibodies. The results of qRT-PCR, western blotting, and pharmacological inhibition tests revealed that US10 is mainly transcribed in the late stage of viral replication. However, the presence of the DNA polymerase inhibitor ganciclovir and the protein synthesis inhibitor cycloheximide blocked transcription. Therefore, US10 is a γ2 (true late) gene. Indirect immunofluorescence analysis showed that US10 proteins were initially diffusely distributed throughout the cytoplasm, but with the passage of time, they gradually relocated to a perinuclear region. The US10 protein was detected in purified DEV virions by mass spectrometry, but was not detected by western blotting, indicating that DEV US10 is a minor virion protein. Conclusions The DEV US10 gene is a γ2 gene and the US10 protein is localized in the perinuclear region. DEV US10 is a virion component.

We report on the development of a heterodyne receiver at mid-infrared wavelength for high-resolution spectroscopy applications. The receiver employs a superconducting NbN hot electron bolometer as a mixer and a room temperature distributed feedback quantum cascade laser operating at 10.6 μm (28.2 THz) as a local oscillator. The stabilization of the heterodyne receiver has been achieved using a feedback loop controlling the output power of the laser. Improved Allan variance times as well as a double sideband receiver noise temperature of 5000 K and a noise bandwidth of 2.8 GHz of the receiver system are demonstrated.

Genomic imprinting is a phenomenon characterized by parent-of-origin-specific gene expression. While widely documented in viviparous mammals and plants, imprinting in oviparous birds remains controversial. Because genomic imprinting is temporal- and tissue-specific, we investigated this phenomenon only in the brain tissues of 1-day-old chickens (Gallus gallus). We used next-generation sequencing technology to compare four transcriptomes pooled from 11 chickens, generated from reciprocally crossed families, to the DNA sequences of their parents. Candidate imprinted genes were then selected from these sequence alignments and subjected to verification experiments that excluded all but one SNP. Subsequent experiments performed with two new sets of reciprocally crossed families resulted in the exclusion of that candidate SNP as well. Attempts to find evidence of genomic imprinting from long non-coding RNAs yielded negative results. We therefore conclude that genomic imprinting is absent in the brains of 1-day-old chickens. However, due to the temporal and tissue specificity of imprinting, our results cannot be extended to all growth stages and tissue types.

Marek's disease (MD) is lymphoproliferative neoplastic disease in chickens, which is caused by Marek's disease virus (MDV). Our previous study profiled microRNA (miRNA) transcriptome in MD lymphoma, and found that gga-miR-199-3p, gga-miR- 140-3p, and gga-miR-221-5p were down-regulated in MD lymphoma. In this study, we further investigated their differential expression between MDV-infected spleens and noninfected spleens at 4, 7, 14, 21, and 28 d postinfection (dpi) to elucidate whether deregulation of them was specific to late tumor transformation phase or not. The results showed that ggamiR- 199-3p was down-regulated at 14 and 28 dpi, and the expression of gga-miR-140-3p was decreased at 14 dpi, which indicated that deregulation of these miRNAs appeared since early stage of MD tumor transformation. Additionally, the inhibitory effects of gga-miR-199-3p, gga-miR-140-3p, and gga-miR-221- 5p on MDV-transformed lymphoid cell line (MSB1) cells proliferation were observed, which suggested that these miRNAs acted as MD tumor suppressors. Their aberrant expression at early tumor transformation phase and suppressive role in cell proliferation indicated that they were involved in MD lymphoma transformation, and might play crucial roles in MD tumorigenesis. [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA) are a class of highly conserved, small noncoding RNA that emerge as key posttranscriptional regulators in various neoplastic transformations. Our previous study profiling the miRNA transcriptome in Marek's disease virus (MDV)-in-duced lymphoma revealed many novel and differentially expressed miRNA, including gga-miR-26a, which was downregulated in MDV-infected spleens of chickens. In this study, differential expression of gga-miR-26a between MDV-infected and noninfected spleens at 4, 7, 14, 21, and 28 d postinfection was analyzed by real-time PCR. The results showed gga-miR-26a were downregulated in MDV-infected spleens at cytolytic infection, latency, and tumor transformation phases. Subsequent cell proliferation assay revealed cell viability was lower in gga-miR,-26a mimic transfection group than that in negative controls. Target genes of gga-miR-26a were identified by luciferase reporter gene assay. The results showed significant interaction between gga-miR-26a and Never In Mitosis Gene A (JV7MA)-related kinase 6 (NEK6) gene. Subsequent gain of function experiment and Western blot assay showed that mRNA and protein levels of NEK6 were downregulated after gga-miR-26 mimic was transfected into MDV-transformed lymphoid cell line (MSB-1), indicating that NEK6 was modulated by gga-miR-26a. The expression of NEK6 showed a higher trend in MDV-infected samples including tumorous spleen and MD lymphoma from liver than that in noninfected controls. The results suggested that gga-miR-26a inhibited MSB-1 cell proliferation. Gga-miR-26a and its direct target, NEK6, might play important roles in MDV infection. [ABSTRACT FROM AUTHOR]

Species of Botryosphaeriaceae fungi are important plant pathogens causing cankers, blight, and fruit rot in an extremely wide range of host. In recent years, kiwifruit rot has been a serious problem in Sichuan Province, one of the important kiwifruit production areas of China. Botryosphaeria dothidea has previously been associated with kiwifruit rot but little is known regarding whether other Botryosphaeriaceae genera also constitute kiwifruit rot pathogens in China. Accordingly, diseased fruit were collected from six different areas of Sichuan Province. Based on morphological characteristics, pathogenicity testing, and comparisons of DNA sequences of the internal transcribed spacer, transcription elongation factor 1-a, and P-tubulin genes, 135 isolates of Botryosphaeriaceae were identified as B. dothidea, Lasiodiplodia theobromae, and Neofusicoccum parvum. All of these species were found to cause kiwifruit rot. To understand the infection cycle of kiwifruit rot pathogens, these three species were used to inoculate leaves and shoots of kiwifruit. The results showed that these species could cause spots on leaves and lesions on shoots, producing abundant pycnidia on leaves and shoots surfaces. Moreover, B. dothidea conidia and ascospores from overwintered pycnidia and pseudothecia in kiwifruit orchards in April and August could cause fruit rot and spots on leaves of kiwifruit. Therefore, we concluded that overwintered pycnidia and pseudothecia of B. dothidea in kiwifruit orchards are the primary inoculum for kiwifruit rot, with new pycnidia that develop during the growing season serving as a secondary inoculum. This is the first report of N. parvum and L. theobromae causing kiwifruit rot in China and is also the first report that B. dothidea is able to overwinter as pycnidia and pseudothecia in kiwifruit orchards and serve as the primary inoculum for kiwifruit rot. [ABSTRACT FROM AUTHOR]