Proteasome subunit beta type 1 interacts directly with Rheb and regulates the cell cycle in Cashmere goat fetal fibroblasts

Yanfeng Wang,Xudong Guo,Zhigang Wang,Zhixin Guo,Mingtao Liu,Keyu Zhao,Xue Feng,Xu Zheng,Xiaojing Wang,Huifang Hao 한국통합생물학회 2017 Animal cells and systems Vol.21 No.5

PSMB1 (proteasome subunit beta type 1) is a core component of the 20S proteasome, and based on its structure, it might have a crucial function in the transcription of certain genes. Rheb (Ras homolog enriched in brain) is a Ras-like small GTPase that acts as an upstream positive regulator of the mechanistic target of rapamycin complex 1 (mTORC1) pathway. We cloned and characterized PSMB1 (KY310590.1) to determine its function in cell cycle progression and proliferation of goat fetal fibroblasts (GFbs). Further, by yeast two-hybrid screen and coimmunoprecipitation, we conformed that PSMB1 interacts directly with Rheb. An siRNA was designed and expressed targeting PSMB1 mRNA in GFbs and inducing cell cycle arrest. Rheb overexpression in GFbs significantly increased the number of S phase cells and growth efficiency compared with control cells. These data indicate that PSMB1 and Rheb have important functions in the cell cycle and proliferation of GFbs, indicating that their interaction governs many processes in GFbs.

Threshold magnetoresistance in anistropic magnetic 2D transition metal dichalcogenides

Xu, Hongjun,Hsu, Ming-Chien,Fuh, Huei-Ru,Feng, Jiafeng,Han, Xiufeng,Zhao, Yanfeng,Zhang, Duan,Wang, Xinming,Liu, Fang,Liu, Huajun,Cho, Jiung,Choi, Miri,Chun, Byong Sun,Ó,Coileá,in, Cormac The Royal Society of Chemistry 2018 Journal of Materials Chemistry C Vol.6 No.12

<P>Recently many novel magnetoresistance (MR) phenomena have been reported from studies of two dimensional (2D) materials. Here, we report on the exotic transport behavior of VS2. A large negative and quadratic MR of −10% is observed for an in-plane magnetic field B up to 14 T. Remarkably, when the applied field deviates from the in-plane orientation there is a threshold field, Bc, and the MR shows a plateau of near zero MR. When B < Bc, only a single state exists and the transition between quantum spin states is forbidden. Our work sheds new light on the MR of magnetic 2D materials with localized states and may spur further investigations.</P>

Generation of Branched-chain Amino Acids Resistant Corynebacterium glutamicum Acetohydroxy Acid Synthase by Site-directed Mutagenesis

Yanfeng Guo,Mei Han,Weiliu Yan,Jianzhong Xu,Weiguo Zhang 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.3

In Corynebacterium glutamicum, acetohydroxyacid synthase (AHAS, encoded by ilvBN) is regulated bythe end products in biosynthesis pathway, which catalyzesthe first common reaction in the biosynthesis of branchedchainamino acids (BCAAs). In this study, conserved A42,A89 and K136 residues in AHAS regulatory subunit werechosen for site-directed mutagenesis, and the resultingmutations A42V, A89V and K136E exhibited higherresistance to inhibition by BCAAs than wild type AHAS. Furthermore, double-mutation was carried out on A42V,A89V and K136E mutations. Expectedly, A42V-A89Vmutation exhibited nearly complete resistance to inhibitionby all three BCAAs, which retained above 93% enzymeactivity even at 10 mM. Strains were further studied toinvestigate the effects of over-expressing different mutantilvBN on the biosynthesis of BCAAs. It was found thatproduction of BCAAs was increased with the increase ofresistance to BCAAs. However, the increase of isoleucineand leucine was slower than valine which showed asignificant increase (up to 86.30 mM). Furthermore, strainsharboring plasmids with different mutant ilvBN couldsignificantly decrease production of alanine (main byproduct). This work gives additional understanding of rolesof A42, A89 and K136 residues and makes the A42V,A89V, K136E and A42V-A89V mutations a good startingpoint for further development by protein engineering.

Experimental Study on Microstructure and Hydraulic Performance of Bentonite Modified Loess

Yanfeng Li,Jian Xu,Zefeng Wang,Bao Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

The impact of natural sodium bentonite on the microstructure, permeability and strengthcharacteristics of bentonite-modified loess (BML) were evaluated by scanning electron microscope(SEM) test, triaxial flexible wall permeability test, uniaxial compression test and direct sheartests. The experimental results indicate that bentonite can be used for loess solidificationattributed to its effective particle filling, water absorption and expansion characteristics. Thequantitative parameters of SEM images such as the average pore area, width, length andsurface porosity of BML declined first and then increased with bentonite content, and thelowest was observed at a bentonite content of 15%. The hydraulic conductivity of BMLdeclined with increasing bentonite content and was lower than the maximum allowable limitof 1.0 × 10−9 m/s. The uniaxial compressive strength and shear strength parameters of BMLincreased initially and subsequently declined as bentonite content increased. A normalizedprediction model was established for modified loess based on the correlation betweenmechanical characteristics and the microscopic pore parameters, which was verified to berational in estimating the macro- and micro-scale properties of BML. Therefore, when theanti-seepage landfill layers are constructed in the Loess Plateau area, 15% of bentonite isrecommended in modified loess, which has optimal impermeability and mechanical properties.

Multi-scale Modeling for the Stress Analysis of Acrylic Joints in a Hybrid Structure

Yanfeng Zheng,Yaozhi Luo,Xian Xu,Chao Yang,Zhongyi Zhu,Yuekun Heng 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.4

The central detector at the Jiangmen Underground Neutrino Observatory (JUNO) is a hybrid structure system consisting of an inner acrylic sphere and an outer stainless steel reticulated shell. The stress distributions of the acrylic joints must be accurately simulated to avoid “crazing”. To balance the accuracy and effi ciency of the stress analysis, a multi-scale modeling method using mixed-dimensional coupling is proposed. A framework and a generalized procedure are developed to instruct the modeling and analysis. A multi-scale model consisting of a single refi ned acrylic joint and equipped with simplifi ed joints is proposed and discussed. A comparison of the results using the multi-scale model with a cluster of 3 × 3 refi ned joints reveals that the diff erence is less than 5%, while the ratio of the computation resource cost and the time consumption is approximately only 1/7 and 1/5, respectively. The stress distributions of the acrylic joints in the central detector are obtained using the proposed multi-scale model.

Influence of Wet-Dry Cycles on Uniaxial Compression Behavior of Fissured Loess Disturbed by Vibratory Loads

Jian Xu,Liyang Zhou,Ke Hu,Yanfeng Li,Xiangang Zhou,Songhe Wang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.5

In this study, the influence of wet-dry cycles on the uniaxial compression behavior of fissured loess after vibration was investigated by small shaking table tests, wet-dry tests, and uniaxial compression tests. Results show that the initial elastic modulus and peak strength both decline after wet-dry cycles while the morphology of stress-strain curves shows insignificant changes. Except for samples with a fissure angle α = 45°, where the bimodal stress-strain curves were observed, all show softening trend. The failure mode can be classified into four main types: fracture failure (α = 0° and 15°), slip-fracture coupled failure (α = 45°), slip failure (α = 60°), and compression shear failure (α = 30° and 90°). The failure modes of samples at α = 0°, 15°, 45°, and 60° are independent of wet-dry cycles but strongly depend on fissure angle, while those at the other fissure angles are more susceptible to wet-dry cycles. The uniaxial compressive strength (UCS) of fissured loess samples before vibration are greater than those after vibration. The relationship between UCS and fissure angle before and after vibration show double-valley pattern. A binary medium model for fissured loess considering vibration and wet-dry cycles was constructed, which was verified by test data.

Surface Quality Controlling Research on High Speed Milling Nickel-Based Superalloy Inconel 718

Yubo Liu,Xu Yanfeng,Xi Wang,Wang Xufeng 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.7

Nickel based superalloy Inconel 718 is difficult to machine as a material. The prediction model of surface roughness in high speed milling of Nickel-based Superalloy Inconel 718 was developed based on multiple regression analysis. The model is established from the experiments conducted on a XH714D matching center. The predicted results by using this model agree very well with those obtained from experiments, and the Prediction model of surface roughness of nickel based superalloy can provide a foundation to optimize cutting parameters and control surface quality.

Direct Interaction between Ras Homolog Enriched in Brain and FK506 Binding Protein 38 in Cashmere Goat Fetal Fibroblast Cells

Wang, Xiaojing,Wang, Yanfeng,Zheng, Xu,Hao, Xiyan,Liang, Yan,Wu, Manlin,Wang, Xiao,Wang, Zhigang Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.12

Ras homolog enriched in brain (Rheb) and FK506 binding protein 38 (FKBP38) are two important regulatory proteins in the mammalian target of rapamycin (mTOR) pathway. There are contradictory data on the interaction between Rheb and FKBP38 in human cells, but this association has not been examined in cashmere goat cells. To investigate the interaction between Rheb and FKBP38, we overexpressed goat Rheb and FKBP38 in goat fetal fibroblasts, extracted whole proteins, and performed coimmunoprecipitation to detect them by western blot. We found Rheb binds directly to FKBP38. Then, we constructed bait vectors (pGBKT7-Rheb/FKBP38) and prey vectors (pGADT7-Rheb/FKBP38), and examined their interaction by yeast two-hybrid assay. Their direct interaction was observed, regardless of which plasmid served as the prey or bait vector. These results indicate that the 2 proteins interact directly in vivo. Novel evidence is presented on the mTOR signal pathway in Cashmere goat cells.

Policy research and energy structure optimization under the constraint of low carbon emissions of Hebei Province in China

Wei Sun,Minquan Ye,Yanfeng Xu 대한환경공학회 2016 Environmental Engineering Research Vol.21 No.4

As a major energy consumption province, the issue about the carbon emissions in Hebei Province, China has been concerned by the government. The carbon emissions can be effectively reduced due to a more rational energy consumption structure. Thus, in this paper the constraint of low carbon emissions is considered as a foundation and four energies--coal, petroleum, natural gas and electricity including wind power, nuclear power and hydro-power etc are selected as the main analysis objects of the adjustment of energy structure. This paper takes energy cost minimum and carbon trading cost minimum as the objective functions based on the economic growth, energy saving and emission reduction targets and constructs an optimization model of energy consumption structure. And empirical research about energy consumption structure optimization in 2015 and 2020 is carried out based on the energy consumption data in Hebei Province, China during the period 1995-2013, which indicates that the energy consumption in Hebei dominated by coal cannot be replaced in the next seven years, from 2014 to 2020, when the coal consumption proportion is still up to 85.93%. Finally, the corresponding policy suggestions are put forward, according to the results of the energy structure optimization in Hebei Province.

Effects of Marbling on Meat Quality Characteristics and Intramuscular Connective Tissue of Beef Longissimus Muscle

Li, Chunbao,Zhou, Guanghong,Xu, Xinglian,Zhang, Jingbo,Xu, Shuqin,Ji, Yanfeng Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.12

This study was designed to explore the effects of marbling on meat quality characteristics and intramuscular connective tissue of beef longissimus muscle. Chemical determinations, histological and mechanical measurements were performed on the raw and cooked meat at d 4 postmortem. The results showed that crude fat, collagen, fiber diameter and maximum transition temperature of intramuscular connective tissue increased (p<0.05) with the increase of marbling score. The cooking losses, collagen solubility, WBSF and perimysial thickness decreased (p<0.05) with the increasing marbling. WBSF correlated (p<0.05) with moisture, crude fat, collagen, cooking losses, sarcomere length and perimysial thickness. The development of marbling results in the decline in cooking losses, the avoidance of sarcomere shortening, and the disorganization of the perimysia, which accounts for the improvement of beef tenderness.