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The neurohormone octopamine regulates many crucial physiological processes in insects and exerts its activity via typical G-protein coupled receptors. The roles of octopamine receptors in regulating behavior and physiology in Coleoptera (beetles) need better understanding. We used the red flour beetle, Tribolium castaneum, as a model species to study the contribution of the octopamine receptor to behavior and physiology. We cloned the cDNA of a β-adrenergic-like octopamine receptor (TcOctβ2R). This was heterologously expressed in human embryonic kidney (HEK) 293 cells and was demonstrated to be functional using an in vitro cyclic AMP assay. In an RNAi assay, injection of dsRNA demonstrated that TcOctβ2R modulates beetle locomotion, mating duration, and fertility. These data present some roles of the octopaminergic signaling system in T. castaneum. Our findings will also help to elucidate the potential functions of individual octopamine receptors in other insects.

The left-right symmetry breaking of vertebrate embryos requires fluid flow (called nodal flow in zebrafish). However, the molecular mechanisms that mediate the asymmetric gene expression regulation under nodal flow remain elusive. In this paper, we report that heat shock factor 1 (HSF1) is asymmetrically activated in the Kuppfer’s vesicle at the early stage of zebrafish embryos in the presence of nodal flow. Deficiency in HSF1 expression caused a significantsitus inversusand disrupted gene expression asymmetry of nodal signaling proteins in zebrafish embryos. Further studies demonstrated that HSF1 could be immediately activated by fluid shear stress. The mechanical sensation ability of HSF1 is conserved in a variety of mechanical stimuli in different cell types. Moreover, cilia and the Ca2+-Akt signaling axis are essential for the activation of HSF1 under mechanical stressin vitroandin vivo. Considering the conserved expression of HSF1 in organisms, these findings unveil a fundamental mechanism of gene expression regulation triggered by mechanical clues during embryonic development and other physiological and pathological transformations.

BACKGROUND Long non-coding RNAs (lncRNAs) play important roles in the regulation of biological processes and have been identified in many species including insects. However, the association between lncRNAs and pesticide resistance in insect species such as Bactrocera dorsalis is unknown. RESULTS RNA-seq was performed on malathion resistant (MR1) and susceptible (MS) strains of B. dorsalis and a total of 6171 lncRNAs transcripts were identified. These included 3728 lincRNAs, 653 antisense lncRNAs, 1402 intronic lncRNAs, and 388 sense lncRNAs. A total of 40 and 52 upregulated lncRNAs were found in females and males of the MR1 strain compared to 54 and 49 in the same sexes of the MS strain, respectively. Twenty-seven of these lncRNAs showed the same trend of expression in both females and males in the MR1 strain, in which 15 lncRNAs were upregulated and 12 were downregulated. RT-qPCR results indicated that the differentially expressed lncRNAs were associated with malathion resistance. The lnc15010.10 and lnc3774.2 were highly expressed in the cuticle of the MR1 strain, indicating that these two lncRNAs may be related to malathion resistance. RNAi of lnc3774.2 and a bioassay showed that malathion resistance was possibly influenced by changes in the B. dorsalis cuticle. CONCLUSION LncRNAs of B. dorsalis potentially related to the malathion resistance were identified. Two lncRNAs appear to influence malathion resistance via modulating the structure, or components, of the cuticle. © 2021 Society of Chemical Industry.

Background The oriental fruit fly, Bactrocera dorsalis (Hendel), is a widespread agricultural pest that has evolved resistance to many commonly used insecticides including malathion. Glutathione S-transferases (GSTs) are multifunctional enzymes that metabolize insecticides directly or indirectly. The specific mechanism used by GSTs to confer malathion resistance in B. dorsalis is unclear. Results BdGSTd9 was identified from B. dorsalis and was expressed at twice the level in a malathion-resistant strain (MR) than in a susceptible strain (MS). By using RNAi of BdGSTd9, the toxicity of malathion against MR was increased. Protein modelling and docking of BdGSTd9 with malathion and malaoxon indicated key amino acid residues for direct binding in the active site. In vitro assays with engineered Sf9 cells overexpressing BdGSTd9 demonstrated lower cytotoxicity of malathion. High performance liquid chromatography (HPLC) analysis indicated that malathion could be broken down significantly by BdGSTd9, and it also could deplete the malathion metabolite malaoxon, which possesses a higher toxicity to B. dorsalis. Taken together, the BdGSTd9 of B. dorsalis could not only deplete malathion, but also react with malaoxon and therefore enhance malathion resistance. Conclusion BdGSTd9 is a component of malathion resistance in B. dorsalis. It acts by depleting both malathion and malaoxon. © 2020 Society of Chemical Industry.

BACKGROUND The oriental fruit fly Bactrocera dorsalis (Hendel), a widespread agricultural pest, has evolved resistance to many insecticides, including organophosphorus compounds. Glutathione S-transferases (GSTs) are involved in xenobiotic detoxification and insecticide resistance in many insects. However, the role of delta class GSTs in detoxifying malathion in B. dorsalis is unknown. Here, we evaluated the roles of two delta class GSTs in malathion detoxification in this species. RESULTS Two delta class GSTs genes, BdGSTd1 and BdGSTd10, were characterized in B. dorsalis. They were highly expressed in 5-day-old adults, as well as in midgut and Malpighian tubules. Upon malathion exposure, the two genes were upregulated by 2.63- and 2.85-fold, respectively. Injection of double-stranded RNA targeting BdGSTd1 or BdGSTd10 significantly reduced their mRNA levels in adults and also significantly increased adult susceptibility to malathion. The expression of these two GSTs in Escherichia coli helped the host to endure malathion stress at a concentration of 10 µg mL-1 according to a Cell Counting Kit-8 assay. High-performance liquid chromatography analyses indicated that malathion could be significantly depleted by the two delta GSTs. The role of BdGSTd10 in malathion sequestration was also discussed. CONCLUSION BdGSTd1 and BdGSTd10 play important roles in the detoxification of malathion in B. dorsalis. © 2019 Society of Chemical Industry.

With the acceleration of the global integration process, Sino-Foreign cooperative graduate education has become increasingly common. However, it has become an important issue about how to ensure the quality of graduate in Sino-Foreign cooperative graduate education. This paper analyzes the current situation of Sino-Foreign cooperative graduate education, summarizes the current quality assurance system, and the current problems. Finally, it puts forward the corresponding suggestions and implementation plan. It will benefit for the cultivation of international talents in the future.

Cells perceive the physical cues such as perturbations of extracellular matrix (ECM) stiffness, and translate these stimuli into biochemical signals controlling various aspects of cell behavior, which contribute to the physiological and pathological processes of multiple organs. In this study, we tested the hypothesis that during arterial stiffening, vascular smooth muscle cells (SMCs) sense the increase of ECM stiffness, which modulates the cellular phenotype through the regulation in DNA methyltransferases 1 (DNMT1) expression. Moreover, we hypothesized that the mechanisms involve intrinsic stiffening and deficiency in contractility of vascular SMCs. Substrate stiffening was mimicked in vitro with polyacrylamide gels. A contractile-to-synthetic phenotypic transition was induced by substrate stiffening in vascular SMCs through the down-regulation of DNMT1 expression. DNMT1 repression was also observed in the tunica media of mice aortas in an acute aortic injury model and a chronic kidney failure model, as well as in the tunica intima of human carotid arteries with calcified atherosclerotic lesions. DNMT1 inhibition facilitates arterial stiffening in vivo and promotes osteogenic transdifferentiation, calcification and cellular stiffening of vascular SMCs in vitro. These effects may be attributable, at least in part, to the role of DNMT1 in regulating the promoter activities of Transgelin (SM22α) and α-smooth muscle actin (SMA) and the functional contractility of SMCs. We conclude that DNMT1 is a critical regulator that negatively regulates arterial stiffening via maintaining the contractile phenotype of vascular SMCs. This research may facilitate elucidation of the complex crosstalk between vascular SMCs and their surrounding matrix in healthy and in pathological conditions and provide new insights into the implications for potential targeting of the phenotypic regulatory mechanisms in material-related therapeutic applications.

Axin interactor, dorsalization-associated (Aida) was identified as a regulatory factor that utilizes its C-terminal region to interact with axis formation inhibitor (Axin). Aida abrogates the Axin-mediated Jun N-terminal kinase activation required for proper dorsalization during zebrafish embryonic development, and thus functions as a proventralization factor. Here, we report the structure of Aida C-terminal fragments, which adopt a conventional C2 domain topology. We also demonstrate that Aida can specifically bind to phosphoinositides in a Ca2+-independent manner, and is able to associate with the cell membrane via a novel positively charged surface, namely a basic loop. Mutation of the positively charged patch on the basic loop leads to destabilization of the Aida–membrane association or disruption of the Aida–Axin interaction, resulting in impaired Jun N-terminal kinase inhibition. Together, our findings provide a molecular basis for C2 domain-mediated Aida–membrane and Aida–Axin associations. Database The atomic coordinates and structure factors of the mouse Aida C2 domain (code: 2QZ5) and the zebrafish Aida C2 domain (code: 2QZQ) have been deposited in the Protein Data Bank (http://www.rcsb.org/) Structured digital abstract AIDA physically interacts with Axin by anti tag coimmunoprecipitation (View interaction)

The AMP-activated protein kinase (AMPK) is characterized by its ability to bind to AMP, which enables it to adjust enzymatic activity by sensing the cellular energy status and maintain the balance between ATP production and consumption in eukaryotic cells. It also has important roles in the regulation of cell growth and proliferation, and in the establishment and maintenance of cell polarity. These important functions have rendered AMPK an important drug target for obesity, type 2 diabetes and cancer treatments. However, the regulatory mechanism of AMPK activity by AMP binding remains unsolved. Here we report the crystal structures of an unphosphorylated fragment of the AMPK alpha-subunit (KD-AID) from Schizosaccharomyces pombe that contains both the catalytic kinase domain and an autoinhibitory domain (AID), and of a phosphorylated kinase domain from Saccharomyces cerevisiae (Snf1-pKD). The AID binds, from the 'backside', to the hinge region of its kinase domain, forming contacts with both amino-terminal and carboxy-terminal lobes. Structural analyses indicate that AID binding might constrain the mobility of helix alphaC, hence resulting in an autoinhibited KD-AID with much lower kinase activity than that of the kinase domain alone. AMP activates AMPK both allosterically and by inhibiting dephosphorylation. Further in vitro kinetic studies demonstrate that disruption of the KD-AID interface reverses the autoinhibition and these AMPK heterotrimeric mutants no longer respond to the change in AMP concentration. The structural and biochemical data have shown the primary mechanism of AMPK autoinhibition and suggest a conformational switch model for AMPK activation by AMP.