Exploration of nucleoprotein <Emphasis Type="Italic">α</Emphasis>-MoRE and XD interactions of Nipah and Hendra viruses

Henipavirus, including Hendra virus (HeV) and Nipah virus (NiV), is a newly discovered human pathogen genus. The nucleoprotein of Henipavirus contains an α-helical molecular recognition element (α-MoRE) that folds upon binding to the X domain (XD) of the phosphoprotein (P). In order to explore the conformational dynamics of free α-MoREs and the underlying binding-folding mechanism with XD, atomic force field-based and hybrid structure-based MD simulations were carried out. In our empirical force field-based simulations, characteristic structures and helicities of α-MoREs reveal the co-existence of partially structured and disordered conformations, as in the case of the well characterized cognate measles virus (MeV) α-MoRE. In spite of their overall similarity, the two α-MoREs display subtle helicity differences in their C-terminal region, but much different from that of MeV. For the α-MoRE/XD complexes, the results of our hybrid structure-based simulations provide the coupled binding-folding landscapes, and unveil a wide conformational selection mechanism at early binding stages, followed by a final induce-fit mechanism selection process. However, the HeV and NiV complexes have a lower binding barrier compared to that of MeV. Moreover, the HeV α-MoRE/XD complex shows much less coupling effects between binding and folding compared to that from both NiV and MeV. Our analysis revealed that contrary to NiV and MeV, the N- and C-terminal regions of the HeV α-MoRE maintains a low helicity also in the bound form.     

Enhanced Ion Conductivity in Conducting Polymer Binder for High‐Performance Silicon Anodes in Advanced Lithium‐Ion Batteries

Polymer binders with high ion and electron conductivities are prepared by assembling ionic polymers (polyethylene oxide and polyethylenimine) onto the electrically conducting polymer poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonate) chains. Crosslinking, chemical reductions, and electrostatics increase the modulus of the binders and maintain the integrity of the anode. The polymer binder shows lithium‐ion diffusivity and electron conductivity that are 14 and 90 times higher than those of the widely used carboxymethyl cellulose (with acetylene black) binder, respectively. The silicon anode with the polymer binder has a high reversible capacity of over 2000 mA h g^?1 after 500 cycles at a current density of 1.0 A g^?1 and maintains a superior capacity of 1500 mA h g^?1 at a high current density of 8.0 A g^?1.     

Interpenetrating Triphase Cobalt‐Based Nanocomposites as Efficient Bifunctional Oxygen Electrocatalysts for Long‐Lasting Rechargeable Zn–Air Batteries

Rational construction of atomic‐scale interfaces in multiphase nanocomposites is an intriguing and challenging approach to developing advanced catalysts for both oxygen reduction (ORR) and evolution reactions (OER). Herein, a hybrid of interpenetrating metallic Co and spinel Co₃O₄ “Janus” nanoparticles stitched in porous graphitized shells (Co/Co₃O₄@PGS) is synthesized via ionic exchange and redox between Co²⁺ and 2D metal–organic‐framework nanosheets. This strategy is proven to effectively establish highways for the transfer of electrons and reactants within the hybrid through interfacial engineering. Specifically, the phase interpenetration of mixed Co species and encapsulating porous graphitized shells provides an optimal charge/mass transport environment. Furthermore, the defect‐rich interfaces act as atomic‐traps to achieve exceptional adsorption capability for oxygen reactants. Finally, robust coupling between Co and N through intimate covalent bonds prohibits the detachment of nanoparticles. As a result, Co/Co₃O₄@PGS outperforms state‐of‐the‐art noble‐metal catalysts with a positive half‐wave potential of 0.89 V for ORR and a low potential of 1.58 V at 10 mA cm^?2 for OER. In a practical demonstration, ultrastable cyclability with a record lifetime of over 800 h at 10 mA cm^?2 is achieved by Zn–air batteries with Co/Co₃O₄@PGS within the rechargeable air electrode.     

Expression Procedure Optimization of <Emphasis Type="Italic">Carassius aurantus</Emphasis> CYP1A in <Emphasis Type="Italic">Shewanella</Emphasis> Using Plasmid Construction Strategy

Cytochrome P4501A (CYP1A) has attracted an increasing interest due to its important role in metabolism of contaminants in aquatic environment and kinds of biomarkers to monitor the pollutants. CYPs are reported to express in E. coli, yeast and insect cells, while expression levels in these systems are too low to continue further study, such as functional and structural research. In this study, we construct an expression system using Shewanella oneidensis to produce goldfish CYP1A. RBS sequence that can elevate expression level by initiating the translation was added. A leading signal peptide which will direct the goal protein into periplasm of the host was introduced. Moreover, large-size plasmid construction strategy was applied during the successful construction process of expression system. At the position of ~60 kDa, a single band was seen clearly after expression; furthermore the amount of expressed CYP1A was as high as 0.02 micromoles per liter in the culture. Heme test was also performed, the result showed the typical P450 hemoprotein spectra. All these data suggest the possible suitable expression system for fish P4501A system was constructed.     

Comparative analysis of conventional and biological treatment in healing of bone disease

The healing of Bone tissue consists of a complex process. Hence, we designed our study to evaluate chondrial diseases, which are as they have a very low healing capacity. Seventy two elderly osteoarthritis (OA) and 54-paediatric juvenile idiopathic arthritis (JIA) patients were included. The group was divided as 24 OA patients and 18 JIA patients in each group. Group I received Hyualuronic acid and glucocorticoides. Group II received platelet rich plasma and fibrin glue. Group III received PRP, fibrin glue, and MSC. 40 control patients received only PRP treatment. Out of 72 OA patients 35 (48.6%) male and 37 (51.4%) female with mean age of 48 ± 6.5 years. 64 (88.9%) Patients had pain and swelling. 52 (72.2%) lacked flexibility. 42 (58.3%) had hypertrophy. 28 (38.9%) had less cartilage thickness. 34 (47.2%) were in grade 3, grade 2 has 28 (38.9%) and grade 1 has 10 (13.9%) patients respectively. Among 54 JIA patients 28 (51.9%) male and 26 (48.1%) female patients with mean, age 4.6 ± 3.8 years. 39 (72.2%) had pain and swelling. 32 (59.3%) lacked flexibility. 29 (53.7%) children’s had functional disability. Group I patients showed 30% improvement with no statistical significance (P < 0.21). Group II showed 45% improvement with statistical significance (P < 0.01). In Group III 80%, improvement was observed with statistical significance (P < 0.001). In 40 control patients, 60% improvement was observed. In conclusion, use of these MSC, PRP, and PPP are safe and less cost effective for treating OA and JIA.     

Low shear stress induces vascular eNOS uncoupling via autophagy-mediated eNOS phosphorylation

Uncoupled endothelial nitric oxide synthase (eNOS) produces O₂^? instead of nitric oxide (NO). Earlier, we reported rapamycin, an autophagy inducer and inhibitor of cellular proliferation, attenuated low shear stress (SS) induced O₂^? production. Nevertheless, it is unclear whether autophagy plays a critical role in the regulation of eNOS uncoupling. Therefore, this study aimed to investigate the modulation of autophagy on eNOS uncoupling induced by low SS exposure. We found that low SS induced endothelial O₂^? burst, which was accompanied by reduced NO release. Furthermore, inhibition of eNOS by L-NAME conspicuously attenuated low SS-induced O₂^? releasing, indicating eNOS uncoupling. Autophagy markers such as LC3 II/I ratio, amount of Beclin1, as well as ULK1/Atg1 were increased during low SS exposure, whereas autophagic degradation of p62/SQSTM1 was markedly reduced, implying impaired autophagic flux. Interestingly, low SS-induced NO reduction could be reversed by rapamycin, WYE-354 or ATG5 overexpression vector via restoration of autophagic flux, but not by N-acetylcysteine or apocynin. eNOS uncoupling might be ascribed to autophagic flux blockade because phosphorylation of eNOS Thr495 by low SS or PMA stimulation was also regulated by autophagy. In contrast, eNOS acetylation was not found to be regulated by low SS and autophagy. Notably, although low SS had no influence on eNOS Ser1177 phosphorylation, whereas boosted eNOS Ser1177 phosphorylation by rapamycin were in favor of the eNOS recoupling through restoration of autophagic flux. Taken together, we reported a novel mechanism for regulation of eNOS uncoupling by low SS via autophagy-mediated eNOS phosphorylation, which is implicated in geometrical nature of atherogenesis.     

PKM2 knockdown influences SREBP activation and lipid synthesis in bovine mammary-gland epithelial MAC-T cells

Objective

The purpose of the article is to evaluate the changes in lipid metabolism in bovine mammary-gland epithelial MAC-T cells after PKM2 knockdown.

Results

MAC-T cells stably expressing low levels of PKM2 were established with lentivirus-mediated small hairpin RNA. Although the knockdown of PKM2 had no effect on MAC-T cell growth, the reduced expression of PKM2 attenuated the mRNA and protein expression of key enzymes involved in sterol synthesis through the SREBP pathway.

Conclusions

The downregulation of PKM2 significantly influenced lipid synthesis in bovine mammary-gland epithelial MAC-T cells. These findings extend our understanding of the crosstalk between glycolysis and lipid metabolism in bovine mammary-gland epithelial cells.

     

Ulk1/FUNDC1 Prevents Nerve Cells from Hypoxia-Induced Apoptosis by Promoting Cell Autophagy

Cell autophagy and cell apoptosis are both observed in the process of hypoxia-induced ischemic cerebral infarction (ICI). Unc-51 like autophagy activating kinase 1 (Ulk1) and FUN14 Domain-containing Protein 1 (FUNDC1) are both involved in the regulation of cell autophagy. This study aimed to investigate the regulatory effects of Ulk1 and FUNDC1 on hypoxia-induced nerve cell autophagy and apoptosis. Cell viability was measured using cell counting kit-8 (CCK-8) assay. Cell apoptosis was detected using Annexin V-PE/7-ADD staining assay. qRT-PCR was used to quantify the mRNA levels of Ulk1 and FUNDC1 in PC-12 cells. Cell transfection was performed to up-regulate the expression of Ulk1. 3-Methyladenine (3-MA) was used as autophagy inhibitor and rapamycin was used as autophagy activator in our experiments. SP600125 was used as c-Jun N-terminal kinase (JNK) inhibitor. Western blotting was performed to analyze the expression levels of key factors that are related to cell autophagy, apoptosis and JNK pathway. We found that hypoxia simultaneously induced apoptosis and autophagy of PC-12 cells. The activation of Ulk1 and FUNDC1 were also found in PC-12 cells after hypoxia induction. Overexpression of Ulk1 promoted the activation of FUNDC1 and prevented PC-12 cells from hypoxia-induced apoptosis. Suppression of Ulk1 had opposite effects. Furthermore, we also found that JNK pathway participated in the effects of Ulk1 overexpression on PC-12 cell apoptosis reduction. To conclude, Ulk1/FUNDC1 played critical regulatory roles in hypoxia-induced nerve cell autophagy and apoptosis. Overexpression of Ulk1 prevented nerve cells from hypoxia-induced apoptosis by promoting cell autophagy.