Expansion of Thaumarchaeota habitat range is correlated with horizontal transfer of ATPase operons.

Thaumarchaeota are responsible for a significant fraction of ammonia oxidation in the oceans and in soils that range from alkaline to acidic. However, the adaptive mechanisms underpinning their habitat expansion remain poorly understood. Here we show that expansion into acidic soils and the high pressures of the hadopelagic zone of the oceans is tightly linked to the acquisition of a variant of the energy-yielding ATPases via horizontal transfer. Whereas the ATPase genealogy of neutrophilic Thaumarchaeota is congruent with their organismal genealogy inferred from concatenated conserved proteins, a common clade of V-type ATPases unites phylogenetically distinct clades of acidophilic/acid-tolerant and piezophilic/piezotolerant species. A presumptive function of pumping cytoplasmic protons at low pH is consistent with the experimentally observed increased expression of the V-ATPase in an acid-tolerant thaumarchaeote at low pH. Consistently, heterologous expression of the thaumarchaeotal V-ATPase significantly increased the growth rate of E. coli at low pH. Its adaptive significance to growth in ocean trenches may relate to pressure-related changes in membrane structure in which this complex molecular machine must function. Together, our findings reveal that the habitat expansion of Thaumarchaeota is tightly correlated with extensive horizontal transfer of atp operons

Peiminine Inhibits Glioblastoma in Vitro and in Vivo Through Cell Cycle Arrest and Autophagic Flux Blocking

Background/Aims: Glioblastoma multiforme (GBM) is the most devastating and widespread primary central nervous system tumour in adults, with poor survival rate and high mortality rates. Existing treatments do not provide substantial benefits to patients; therefore, novel treatment strategies are required. Peiminine, a natural bioactive compound extracted from the traditional Chinese medicine Fritillaria thunbergii, has many pharmacological effects, especially anticancer activities. However, its anticancer effects on GBM and the underlying mechanism have not been demonstrated. This study was conducted to investigate the potential antitumour effects of peiminine in human GBM cells and to explore the related molecular signalling mechanisms in vitro and in vivo Methods: Cell viability and proliferation were detected with MTT and colony formation assays. Morphological changes associated with autophagy were assessed by transmission electron microscopy (TEM). The cell cycle rate was measured by flow cytometry. To detect changes in related genes and signalling pathways in vitro and in vivo, RNA-seq, Western blotting and immunohistochemical analyses were employed. Results: Peiminine significantly inhibited the proliferation and colony formation of GBM cells and resulted in changes in many tumour-related genes and transcriptional products. The potential anti-GBM role of peiminine might involve cell cycle arrest and autophagic flux blocking via changes in expression of the cyclin D1/CDK network, p62 and LC3. Changes in Changes in flow cytometry results and TEM findings were also observed. Molecular alterations included downregulation of the expression of not only phospho-Akt and phospho-GSK3β but also phospho-AMPK and phospho-ULK1. Furthermore, overexpression of AKT and inhibition of AKT reversed and augmented peiminine-induced cell cycle arrest in GBM cells, respectively. The cellular activation of AMPK reversed the changes in the levels of protein markers of autophagic flux. These results demonstrated that peiminine mediates cell cycle arrest by suppressing AktGSk3β signalling and blocks autophagic flux by depressing AMPK-ULK1 signalling in GBM cells. Finally, peiminine inhibited the growth of U251 gliomas in vivo. Conclusion: Peiminine inhibits glioblastoma in vitro and in vivo via arresting the cell cycle and blocking autophagic flux, suggesting new avenues for GBM therapy

Genetic Insights into Intestinal Microbiota and Risk of Infertility: A Mendelian Randomization Study

Background: The interaction between intestinal microbiota and infertility is less researched. This study was performed to investigate the causal association between gut microbiota and infertility. Methods: In this two-sample Mendelian randomization (MR) study, genetic variants of intestinal microbiota were obtained from the MiBioGen consortium, which included 18,340 individuals. Inverse variance weighting (IVW), MR-Egger, weighted median, maximum likelihood, MR Robust adjusted profile score, MR Pleiotropy residual sum, and outlier (MR-PRESSO) methods were used to explore the causal links between intestinal microbiota and infertility. The MR-Egger intercept term and the global test from the MR-PRESSO estimator were used to assess the horizontal pleiotropy. The Cochran Q test was applied to evaluate the heterogeneity of instrumental variables (IVs). Results: As indicated by the IVW estimator, significantly protective effects of the Family XIII AD3011 group (OR = 0.87) and Ruminococcaceae NK4A214 group (OR = 0.85) were identified for female fertility, while Betaproteobacteria (OR = 1.18), Burkholderiales (OR = 1.18), Candidatus Soleaferrea (OR = 1.12), and Lentisphaerae (OR = 1.11) showed adverse effects on female fertility. Meanwhile, Bacteroidaceae (OR = 0.57), Bacteroides (OR = 0.57), and Ruminococcaceae NK4A214 group (OR = 0.61) revealed protective effects on male fertility, and a causal association between Anaerotruncus (OR = 1.81) and male infertility was detected. The effect sizes and directions remained consistent in the other five methods except for Candidatus Soleaferrea. No heterogeneity or pleiotropy were identified by Cochran’s Q test, MR-Egger, and global test (all p > 0.05). Conclusions: This two-sample MR study revealed that genetically proxied intestinal microbiota had potentially causal effects on infertility. In all, the Ruminococcaceae NK4A214 group displayed protective effects against both male and female infertility. Further investigations are needed to establish the biological mechanisms linking gut microbiota and infertility

Synthesis of Dimethyl Carbonate from CO2 and Methanol over Zr-Based Catalysts with Different Chemical Environments

The adsorption and activation of both CO2 and methanol are mainly affected by the distance of the Lewis acid site, Zr4+, and Lewis base, Zr4+/O2−, of the Zr-based catalysts. In this paper, Zr-incorporated SBA-15 (Zr-SBA-15) and Zr-grafted SBA-15 (Zr/SBA-15) catalysts were prepared with different Zr environments, and were analyzed with N2 adsorption–desorption isotherms, X-ray diffraction, UV-vis spectra, and XPS. It was proposed that Zr-SBA-15 catalyst with Si-O-Zr-OH and Zr-O-Si-OH structure exhibited non-adjacent sites between Zr4+ and Zr4+/O2−, while Zr/SBA-15 catalyst with Zr-O-Zr-OH structure showed neighboring sites between Zr4+ and Zr4+/O2−. Furthermore, the Zr/SBA-15 catalyst exhibited good catalytic activity, while no DMC was detected over the Zr-SBA-15 catalyst at the same reaction conditions. For combined in situ infrared and catalytic performance, it was indicated that the methanol and CO2 could be activated to form DMC, only when the Zr4+ and Zr4+/O2− sites existed and were adjacent to each other in the Zr-O-Zr-OH of Zr/SBA-15 catalyst

Construction of Baculovirus-Inducible CRISPR/Cas9 Antiviral System Targeting BmNPV in <i>Bombyx mori</i>

The silkworm Bombyx mori is an economically important insect. The sericulture industry is seriously affected by pathogen infections. Of these pathogens, Bombyx mori nucleopolyhedrovirus (BmNPV) causes approximately 80% of the total economic losses due to pathogen infections. We previously constructed a BmNPV-specific CRISPR/Cas9 silkworm line with significantly enhanced resistance to BmNPV. In order to optimize the resistance properties and minimize its impact on economic traits, we constructed an inducible CRISPR/Cas9 system for use in transgenic silkworms. We used the 39k promoter, which is induced by viral infection, to express Cas9 and the U6 promoter to express four small guide RNA targeting the genes encoding BmNPV late expression factors 1 and 3 (lef-1 and lef-3, respectively), which are essential for viral DNA replication. The system was rapidly activated when the silkworm was infected and showed considerably higher resistance to BmNPV infection than the wild-type silkworm. The inducible system significantly reduced the development effects due to the constitutive expression of Cas9. No obvious differences in developmental processes or economically important characteristics were observed between the resulting transgenic silkworms and wild-type silkworms. Adoption of this accurate and highly efficient inducible CRISPR/Cas9 system targeting BmNPV DNA replication will result in enhanced antivirus measures during sericulture, and our work also provides insights into the broader application of the CRISPR/Cas9 system in the control of infectious diseases and insect pests

Isogambogenic Acid Inhibits the Growth of Glioma Through Activation of the AMPK-mTOR Pathway

Background/Aims: Glioma is the most devastating cancer in the brain and has a poor prognosis in adults. Therefore, there is a critical need for novel therapeutic strategies for the management of glioma patients. Isogambogenic acid, an active compound extracted from the Chinese herb Garcinia hanburyi, induces autophagic cell death. Methods: Cell viability was detected with MTT assays. Cell proliferation was assessed using the colony formation assay. Morphological changes associated with autophagy and apoptosis were tested by TEM and Hoechst staining, respectively. The apoptosis rate was measured by flow cytometry. Western blot, immunofluorescence and immunohistochemical analyses were used to detect protein expression. U87-derived xenografts were established for the examination of the effect of isogambogenic acid on glioma growth in vivo. Results: Isogambogenic acid induced autophagic death in U87 and U251 cells, and blocking late-stage autophagy markedly enhanced the antiproliferative activities of isogambogenic acid. Moreover, we observed the activation of AMPK-mTOR signalling in isogambogenic acid-treated glioma cells. Furthermore, the activation of AMPK or the inhibition of mTOR augmented isogambogenic acid-induced autophagy. Inhibition of autophagy attenuated apoptosis in isogambogenic acid-treated glioma cells. Finally, isogambogenic acid inhibited the growth of U87 glioma in vivo. Conclusion: Isogambogenic acid inhibits the growth of glioma via activation of the AMPK-mTOR signalling pathway, which may provide evidence for future clinical applications in glioma therapy

CRISPR/Cas9-Mediated Disruption of the <i>lef8</i> and <i>lef9</i> to Inhibit Nucleopolyhedrovirus Replication in Silkworms

Bombyx mori nucleopolyhedrovirus (BmNPV) is a pathogen that causes severe disease in silkworms. In a previous study, we demonstrated that by using the CRISPR/Cas9 system to disrupt the BmNPV ie-1 and me53 genes, transgenic silkworms showed resistance to BmNPV infection. Here, we used the same strategy to simultaneously target lef8 and lef9, which are essential for BmNPV replication. A PCR assay confirmed that double-stranded breaks were induced in viral DNA at targeted sequences in BmNPV-infected transgenic silkworms that expressed small guide RNAs (sgRNAs) and Cas9. Bioassays and qPCR showed that replication of BmNPV and mortality were significantly reduced in the transgenic silkworms in comparison with the control groups. Microscopy showed degradation of midgut cells in the BmNPV-infected wild type silkworms, but not in the transgenic silkworms. These results demonstrated that transgenic silkworms using the CRISPR/Cas9 system to disrupt BmNPV lef8 and lef9 genes could successfully prevent BmNPV infection. Our research not only provides more alternative targets for the CRISPR antiviral system, but also aims to provide new ideas for the application of virus infection research and the control of insect pests

The Prmt5-Vasa module is essential for spermatogenesis in Bombyx mori.

In lepidopteran insects, dichotomous spermatogenesis produces eupyrene spermatozoa, which are nucleated, and apyrene spermatozoa, which are anucleated. Both sperm morphs are essential for fertilization, as eupyrene sperm fertilize the egg, and apyrene sperm is necessary for the migration of eupyrene sperm. In Drosophila, Prmt5 acts as a type II arginine methyltransferase that catalyzes the symmetrical dimethylation of arginine residues in the RNA helicase Vasa. Prmt5 is critical for the regulation of spermatogenesis, but Vasa is not. To date, functional genetic studies of spermatogenesis in the lepidopteran model Bombyx mori has been limited. In this study, we engineered mutations in BmPrmt5 and BmVasa through CRISPR/Cas9-based gene editing. Both BmPrmt5 and BmVasa loss-of-function mutants had similar male and female sterility phenotypes. Through immunofluorescence staining analysis, we found that the morphs of sperm from both BmPrmt5 and BmVasa mutants have severe defects, indicating essential roles for both BmPrmt5 and BmVasa in the regulation of spermatogenesis. Mass spectrometry results identified that R35, R54, and R56 of BmVasa were dimethylated in WT while unmethylated in BmPrmt5 mutants. RNA-seq analyses indicate that the defects in spermatogenesis in mutants resulted from reduced expression of the spermatogenesis-related genes, including BmSxl, implying that BmSxl acts downstream of BmPrmt5 and BmVasa to regulate apyrene sperm development. These findings indicate that BmPrmt5 and BmVasa constitute an integral regulatory module essential for spermatogenesis in B. mori