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"Molecular weight and its distribution, molecular structure composition, curing characteristics, Mooney viscosity, physical and mechanical property, thermal-oxidative aging resistance, low temperature performance and catalyst residual amount of similar brand hydrogenated nitrile rubber (HNBR) products from Zannan SciTech Co Ltd and Zeon Corporation of Japan were mainly compared. The results showed that molecular weight and its distribution, molecular structure composition, Mooney viscosity of raw rubber, scorch time of compound, thermal-oxidative aging resistance and low temperature performance of HNBR ZN 35156 from Zannan SciTech Co Ltd were generally equivalent to those of Zetpol 2010 L from Zeon Corporation, and compared with Zetpol 2010 L, ZN 35156 raw rubber had somewhat lower saturation degree, and ZN 35156 compound had a little faster curing rate and slightly poorer processing performance, while ZN 35156 vulcanizate had slightly superior physical and mechanical properties such as hardness and tensile strength; molecular weight and its distribution, molecular structure composition, Mooney viscosity of raw rubber, scorch time of compound and thermal-oxidative aging resistance of HNBR ZN 35158 from Zannan SciTech Co Ltd were basically similar to those of Zetpol 2010 from Zeon Corporation, and compared with Zetpol 2010, bound acrylonitrile content of ZN 35158 raw rubber was greater, ZN 35158 compound had a little faster curing rate and slightly poorer processing performance, and ZN 35158 vulcanizate had slightly poorer low temperature performance, while ZN 35158 vulcanizate had slightly superior physical and mechanical properties such as hardness and tensile strength; hydrogenation catalysts of Zannan SciTech Co Ltd and Zeon Corporation were ruthenium-based catalyst and palladium-based catalysts, respectively, and catalyst residual amounts in HNBR products of Zannan SciTech Co Ltd were re-latively less. "

BACKGROUND: Golgi apparatus (GA) is assembled as a crescent-like ribbon in mammalian cells under immunofluorescence microscope without knowing the shaping mechanisms. It is estimated that roughly 1/5 of the genes encoding kinases or phosphatases in human genome participate in the assembly of Golgi ribbon, reflecting protein modifications play major roles in building Golgi ribbon. METHODS: To explore how Golgi ribbon is shaped as a crescent-like structure under the guidance of protein modifications, we identified a protein complex containing the scaffold proteins Ajuba, two known GA regulators including the protein kinase Aurora-A and the protein arginine methyltransferase PRMT5, and the common substrate of Aurora-A and PRMT5, HURP. Mutual modifications and activation of PRMT5 and Aurora-A in the complex leads to methylation and in turn phosphorylation of HURP, thereby producing HURP p725. The HURP p725 localizes to GA vicinity and its distribution pattern looks like GA morphology. Correlation study of the HURP p725 statuses and GA structure, site-directed mutagenesis and knockdown-rescue experiments were employed to identify the modified HURP as a key regulator assembling GA as a crescent ribbon. RESULTS: The cells containing no or extended distribution of HURP p725 have dispersed GA membranes or longer GA. Knockdown of HURP fragmentized GA and HURP wild type could, while its phosphorylation deficiency mutant 725A could not, restore crescent Golgi ribbon in HURP depleted cells, collectively indicating a crescent GA-constructing activity of HURP p725. HURP p725 is transported, by GA membrane-associated ARF1, Dynein and its cargo adaptor Golgin-160, to cell center where HURP p725 forms crescent fibers, binds and stabilizes Golgi assembly factors (GAFs) including TRIP11, GRASP65 and GM130, thereby dictating the formation of crescent Golgi ribbon at nuclear periphery. CONCLUSIONS: The Ajuba/PRMT5/Aurora-A complex integrates the signals of protein methylation and phosphorylation to HURP, and the HURP p725 organizes GA by stabilizing and recruiting GAFs to its crescent-like structure, therefore shaping GA as a crescent ribbon. Therefore, the HURP p725 fiber serves a template to construct GA according to its shape. Video Abstract.

Abstract Background Golgi apparatus (GA) is assembled as a crescent-like ribbon in mammalian cells under immunofluorescence microscope without knowing the shaping mechanisms. It is estimated that roughly 1/5 of the genes encoding kinases or phosphatases in human genome participate in the assembly of Golgi ribbon, reflecting protein modifications play major roles in building Golgi ribbon. Methods To explore how Golgi ribbon is shaped as a crescent-like structure under the guidance of protein modifications, we identified a protein complex containing the scaffold proteins Ajuba, two known GA regulators including the protein kinase Aurora-A and the protein arginine methyltransferase PRMT5, and the common substrate of Aurora-A and PRMT5, HURP. Mutual modifications and activation of PRMT5 and Aurora-A in the complex leads to methylation and in turn phosphorylation of HURP, thereby producing HURP p725. The HURP p725 localizes to GA vicinity and its distribution pattern looks like GA morphology. Correlation study of the HURP p725 statuses and GA structure, site-directed mutagenesis and knockdown-rescue experiments were employed to identify the modified HURP as a key regulator assembling GA as a crescent ribbon. Results The cells containing no or extended distribution of HURP p725 have dispersed GA membranes or longer GA. Knockdown of HURP fragmentized GA and HURP wild type could, while its phosphorylation deficiency mutant 725A could not, restore crescent Golgi ribbon in HURP depleted cells, collectively indicating a crescent GA-constructing activity of HURP p725. HURP p725 is transported, by GA membrane-associated ARF1, Dynein and its cargo adaptor Golgin-160, to cell center where HURP p725 forms crescent fibers, binds and stabilizes Golgi assembly factors (GAFs) including TRIP11, GRASP65 and GM130, thereby dictating the formation of crescent Golgi ribbon at nuclear periphery. Conclusions The Ajuba/PRMT5/Aurora-A complex integrates the signals of protein methylation and phosphorylation to HURP, and the HURP p725 organizes GA by stabilizing and recruiting GAFs to its crescent-like structure, therefore shaping GA as a crescent ribbon. Therefore, the HURP p725 fiber serves a template to construct GA according to its shape. Video Abstract

Pumpkin (Cucurbita moschata Duch.) productivity is severely hindered by powdery mildew (PM) worldwide. The causative agent of pumpkin PM is Podosphaera xanthii, a biotrophic fungus. Pathogenesis-related protein 1 (PR1) homolog was previously identified from transcriptomic analysis of a PM-resistant pumpkin. Here, we investigated the effects of CmPR1 gene from pumpkin for resistance to PM. Subcellular localization assay revealed that CmPR1 is a cytoplasmic protein in plants. The expression of CmPR1 gene was strongly induced by P. xanthii inoculation at 48 h and exogenous ethylene (ET), jasmonic acid (JA) and NaCl treatments, but repressed by H2O2 and salicylic acid (SA) treatments. Visual disease symptoms, histological observations of fungal growth and host cell death, and accumulation of H2O2 in transgenic tobacco plants indicated that CmPR1 overexpression significantly enhanced the resistance to Golovinomyces cichoracearum compared to wild type plants during PM pathogens infection, possibly due to inducing cell death and H2O2 accumulation near infected sites. The expression of PR1a was significantly induced in transgenic tobacco plants in response to G. cichoracearum, suggesting that CmPR1 overexpression positively modulates the resistance to PM via the SA signaling pathway. These findings indicate that CmPR1 is a defense response gene in C. moschata and can be exploited to develop disease-resistant crop varieties.

Collective cell migration mediates multiple tissue morphogenesis processes. Yet how multi-dimensional mesenchymal cell movements are coordinated remains mostly unknown. Here we report that coordinated mesenchymal cell migration during chicken feather elongation is accompanied by dynamic changes of bioelectric currents. Transcriptome profiling and functional assays implicate contributions from functional voltage-gated Ca2+ channels (VGCCs), Connexin-43 based gap junctions, and Ca2+ release activated Ca2+ (CRAC) channels. 4-Dimensional Ca2+ imaging reveals that the Sonic hedgehog-responsive mesenchymal cells display synchronized Ca2+ oscillations, which expand progressively in area during feather elongation. Inhibiting VGCCs, gap junctions, or Sonic hedgehog signaling alters the mesenchymal Ca2+ landscape, cell movement patterns and feather bud elongation. Ca2+ oscillations induced by cyclic activation of opto-cCRAC channels enhance feather bud elongation. Functional disruption experiments and promoter analysis implicate synergistic Hedgehog and WNT/β-Catenin signaling in activating Connexin-43 expression, establishing gap junction networks synchronizing the Ca2+ profile among cells, thereby coordinating cell movement patterns.

The high therapeutic resistance of tumor is the primary cause behind tumor recurrence and incurability. In recent years, scientists have devoted themselves to find a variety of treatments to solve this problem. Herein, we propose a multi-hit strategy that is based on the biodegradable hollow mesoporous Prussian blue (HMPB)-based nanosystem for tumor-specific therapy that encapsulated the critical heat shock protein 90 (HSP90) inhibitor 17-dimethylamino-ethylamino-17-demethoxydeldanamycin (17-DMAG). The nanosystem was further modified using thermotropic phase transition material star-PEG-PCL (sPP) and hyaluronic acid (HA), which offers near infrared light (NIR) responsive release characteristic, as well as enhanced tumor cell endocytosis. Upon cell internalization of 17-DMAG-HMPB@sPP@HA and under 808 nm laser irradiation, photothermal-conversion effect of HMPB directly kills cells using hyperthermia, which further causes phase transition of sPP to trigger release of 17-DMAG, inhibits HSP90 activity and blocks multiple signaling pathways, including cell cycle, Akt and HIF pathways. Additionally, the down-regulation of GPX4 protein expression by 17-DMAG and the release of ferric and ferrous ions from gradual degradation of HMPB in the endogenous mild acidic microenvironment in tumors promoted the occurrence of ferroptosis. Importantly, the antitumor effect of 17-DMAG and ferroptosis damage were amplified using photothermal effect of HMPB by accelerating release of ferric and ferrous ions, and reducing HSP90 expression in cells, which induced powerful antitumor effect in vitro and in vivo. This multi-hit therapeutic nanosystem helps provide a novel perspective for solving the predicament of cancer treatment, as well as a promising strategy for design of a novel cancer treatment nanoplatform.

The microstructure, curing characteristics, physical and mechanical properties, wear resistance and aging resistance of eight brands of ethylene propylene diene monomer (EPDM) were compared. The results showed that the mass fraction of the third monomer vinylidene norbornene (ENB) in EPDM affected the curing rate of EPDM. Among the 8 brands, the curing rate of EPDM 9950 C was the fastest and that of EPDM 3722 was the slowest. The curing rate of oil filled EPDM 3666 was similar to that of EPDM with similar structure, but the maximum torque and minimum torque of EPDM 3666 vulcanizate decreased significantly. EPDM 6470 and EPDM 5890 F vulcanizates with high mass fraction of vinyl had higher tensile strength, modulus at 300% and Shore A hardness, and better tear resistance, wear resistance and resilience. The compression set of EPDM 9950 C and EPDM 4570 with higher relative molecular weight was the smallest, and the compression set of EPDM 3722 vulcanizate with more than 90% mass fraction of vinyl was the largest. The tensile strength and Shore A hardness of EPDM with small relative molecular weight and oil filled EPDM were lower. The aging resistance of eight brands of EPDM was good, among which EPDM 3722 with the lowest mass fraction of ENB had the best aging resistance.

In this experiment, five different parts of beef were selected to make boletus beef sauce, namely beef hind leg (BHL), beef shoulder (BS), beef knuckle (BK), beef brisket (BB), and beef tendon (BT), and the effects of different beef parts on the quality and volatile aroma components of spicy beef boletus sauce were investigated. The boletus beef sauce made from BB reported the highest sensory score of 87.4. In terms of texture, beef sauce made from BB exhibited the best quality, with hardness, elasticity, gumminess, and chewiness values of 14.01 N, 4.71 mm, 3.22 N, and 15.30 mJ, respectively. Significant differences (P<0.05) in color of beef sauce were observed among different beef parts based on the L* and a* values. Electronic nose could effectively distinguish the spicy beef boletus sauce made from different parts of beef. In terms of flavor substances, 84 volatile flavor substances were detected in BHL, 36 in BS, 52 in BT, 102 in BK, and 87 in BB. The main aroma components were consistent with the types of sensitive substances identified by the electronic nose. Among them, hexanal, D-limonene, α-pinene, diallyl disulfide, and anethole were the common aroma components in the five parts, with ROAV>1. In summary, the BB was proven to be the best raw material in making spicy beef boletus sauce. These research findings provide a theoretical basis and data reference for the future cooking process and flavor characteristics of beef sauce. [ABSTRACT FROM AUTHOR]

High‐performance biosensors play a crucial role in elucidating the intricate spatiotemporal regulatory roles and dynamics of membrane phospholipids. However, enhancing the sensitivity and imaging performance remains a significant challenge. Here, optogenetic‐based strategies are presented to optimize phospholipid biosensors. These strategies involves presequestering unbound biosensors in the cell nucleus and regulating their cytosolic levels with blue light to minimize background signal interference in phospholipid detection, particularly under conditions of high expression levels of biosensor. Furthermore, optically controlled phase separation and the SunTag system are employed to generate punctate probes for substrate detection, thereby amplifying biosensor signals and enhancing visualization of the detection process. These improved phospholipid biosensors hold great potential for enhancing the understanding of the spatiotemporal dynamics and regulatory roles of membrane lipids in live cells and the methodological insights in this study might be valuable for developing other high‐performance biosensors. [ABSTRACT FROM AUTHOR]

Background: Alcohol use disorder (AUD) is a complex condition, and it remains unclear which specific neuronal substrates mediate alcohol‐seeking and ‐taking behaviors. Engram cells and their related ensembles, which encode learning and memory, may play a role in this process. We aimed to assess the precise neural substrates underlying alcohol‐seeking and ‐taking behaviors and determine how they may affect one another. Methods: Using FLiCRE (Fast Light and Calcium‐Regulated Expression; a newly developed technique which permits the trapping of acutely activated neuronal ensembles) and operant self‐administration (OSA), we tagged striatal neurons activated during alcohol‐taking behaviors. We used FLiCRE to express an inhibitory halorhodopsin in alcohol‐taking neurons, permitting loss‐of‐function manipulations. Results: We found that the inhibition of OSA‐tagged alcohol‐taking neurons decreased both alcohol‐seeking and ‐taking behaviors in future OSA trials. In addition, optogenetic inhibition of these OSA‐tagged alcohol‐taking neurons during extinction training facilitated the extinction of alcohol‐seeking behaviors. Furthermore, inhibition of these OSA‐tagged alcohol‐taking neurons suppressed the reinstatement of alcohol‐seeking behaviors, but, interestingly, it did not significantly suppress alcohol‐taking behaviors during reinstatement. Conclusions: Our findings suggest that alcohol‐taking neurons are crucial for future alcohol‐seeking behaviors during extinction and reinstatement. These results may help in the development of new therapeutic approaches to enhance extinction and suppress relapse in individuals with AUD. [ABSTRACT FROM AUTHOR]

In this article, Fe–8.5Mn–1.5Al medium‐manganese steel is taken as the research object, and Gleeble 3500 thermal simulation testing machine is used to conduct isothermal compression at different deformation temperatures, strain rates, and strains in its austenite ferrite two‐phase zone. A constitutive model and a dynamic recrystallization volume fraction model for materials are established, and finite‐element method is used to simulate the temperature, equivalent strain, and dynamic recrystallization volume fraction distribution in different regions of the workpiece under different deformation conditions. By comparing and analyzing the microstructure, finite‐element simulation results, and hot working diagrams obtained from the experiment, the microscopic mechanism of dynamic softening of the material when ferrite and austenite coexist is explained; the transformation of the dynamic softening mechanism of the two phases with the hot deformation process is also explained. Early deformation mainly occurs in softer ferrite, which preferentially undergoes continuous dynamic recrystallization. Austenite has a lower stacking fault energy, and discontinuous dynamic recrystallization (DDRX) occurs when the dislocation density reaches a certain critical value. At the same time, when the strain reaches a certain level, the dynamic softening behavior of ferrite will also transform into DDRX. The optimal deformation conditions for Fe–8.5Mn–1.5Al medium‐manganese steel during warm processing in the two‐phase zone are a temperature of 720 °C, a strain rate of 0.01 s−1, and a large deformation zone. [ABSTRACT FROM AUTHOR]

Synechocystis sp. strain PCC 6803 has been widely used as a photo-biorefinery chassis. Based on its genome annotation, this species contains a complete TCA cycle, an Embden-Meyerhof-Parnas pathway (EMPP), an oxidative pentose phosphate pathway (OPPP), and an Entner-Doudoroff pathway (EDP). To evaluate how Synechocystis 6803 catabolizes glucose under heterotrophic conditions, we performed 13 C metabolic flux analysis, metabolite pool size analysis, gene knockouts, and heterologous expressions. The results revealed a cyclic mode of flux through the OPPP. Small, but non-zero, fluxes were observed through the TCA cycle and the malic shunt. Independent knockouts of 6-phosphogluconate dehydrogenase (gnd) and malic enzyme (me) corroborated these results, as neither mutant could grow under dark heterotrophic conditions. Our data also indicate that Synechocystis 6803 metabolism relies upon oxidative phosphorylation to generate ATP from NADPH under dark or insufficient light conditions. The pool sizes of intermediates in the TCA cycle, particularly acetyl-CoA, were found to be several fold lower in Synechocystis 6803 (compared to E. coli metabolite pool sizes), while its sugar phosphate intermediates were several-fold higher. Moreover, negligible flux was detected through the native, or heterologous, EDP in the wild type or Δgnd strains under heterotrophic conditions. Comparing photoautotrophic, photomixotrophic, and heterotrophic conditions, the Calvin cycle, OPPP, and EMPP in Synechocystis 6803 possess the ability to regulate their fluxes under various growth conditions (plastic), whereas its TCA cycle always maintains at low levels (rigid). This work also demonstrates how genetic profiles do not always reflect actual metabolic flux through native or heterologous pathways. Biotechnol. Bioeng. 2017;114: 1593-1602. © 2017 Wiley Periodicals, Inc.