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Duplication and diversification of insulin genes in ray-finned fish

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Zoological Research 2019年第3期40卷 185-197页

作者： David M.Irwin Department of Laboratory Medicine and Pathobiology University of Toronto Banting and Best Diabetes Centre University of Toronto

Insulin is a key hormone for the regulation of metabolism in vertebrates.Insulin is produced by pancreatic islet cells in response to elevated glucose levels and leads to the uptake of glucose by tissues such as liver and adipose tissue to store energy.Insulin also has additional functions in regulating development.Previous work has shown that the proglucagon gene,which encodes hormones counter regulating insulin,is duplicated in teleost fish,and that the peptide hormones encoded by these genes have diversified in function.I sought to determine whether similar processes have occurred to insulin genes in these species.Searches of fish genomes revealed an unexpected diversity of insulin genes.A triplication of the insulin gene occurred at the origin of teleost fish,however one of these three genes,insc,has been lost in most teleost fish lineages.The two other insulin genes,insa and insb,have been retained but show differing levels of selective constraint suggesting that they might have diversified in function.Intriguingly,a duplicate copy of the insa gene,which I named insab,is found in many fish.The coding sequenee encoded by insab genes is under weak selective constraint,with its predicted protein sequences losing their potential to be processed into a two-peptide hormone.However,these sequences have retained perfectly conserved cystine residues,suggesting that they maintain insulin's three-dimensional structure and therefore might modulate the processing and secretion of insulin produced by the other genes.

关键词： Insulin Teleost fish Gene duplicati on Adaptive evolution Gene loss

Does environmental infrastructure investment contribute to emissions reduction?A case of China

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Frontiers in Energy 2020年第1期14卷 57-70页

作者： Xiaoqian SonG Yong GENG Ke LI Xi ZHANG Fei WU Hengyu PAN Yiqing ZHANG China Institute of Urban Governance Shanghai Jiao Tong UniversityShanghai200030China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China China Institute of Urban Governance Shanghai Jiao Tong UniversityShanghai 200030China School of Management China University of Mining and TechnologyXuzhou 221116China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China College o f Mathematics&Computer Science Hunan Normal UniversityChangsha 410081China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Centre for Energy Economy of Shandong Shandong Technology and Business UniversityYantai 264005China

Environmental infrastructure investment(EII)is an important environmental policy instrument on responding to greenhouse gas(GHG)emission and air pollution.This paper employs an improved stochastic impact by regression on population,affluence and technology(STRIPAT)model by using panel data from 30 Chinese provinces and municipalities for the period of 2003–2015 to investigate the effect of EII on CO2 emissions,SO2 emissions,and PM2.5 pollution.The results indicate that EII has a positive and significant effect on mitigating CO2 emission.However,the effect of EII on SO2 emission fluctuated although it still contributes to the reduction of PM2.5 pollution through technology innovations.Energy intensity has the largest impact on GHG emissions and air pollution,followed by GDP per capita and industrial structure.In addition,the effect of EII on environmental issues varies in different regions.Such findings suggest that policies on EII should be region-specific so that more appropriate mitigation policies can be raised by considering the local realities.

关键词： environmental infrastructure investment(EII) CO2 emission SO2 emission PM2.5 pollution stochastic impact by regression on population affluence and technology(STIRPAT)model governance

A family of high-temperature ferromagnetic monolayers with locked spin-dichroism-mobility anisotropy: MnNX and CrCX(X=Cl,Br,I;C=S,Se,Te)

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Science Bulletin 2019年第5期64卷 293-300页

作者： Cong Wang Xieyu Zhou Linwei Zhou Ning-Hua Tong Zhong-Yi Lu Wei Ji Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices Department of Physics Renmin University of China

Two-dimensional magnets have received increasing attention since Cr_2Ge_2Te_6 and CrI_3 were experimentally exfoliated and measured in 2017. Although layered ferromagnetic metals were demonstrated at room temperature, a layered ferromagnetic semiconductor with high Curie temperature(Tc) is yet to be unveiled. Here, we theoretically predicted a family of high Tcferromagnetic monolayers, namely MnNX and CrCX(X = Cl, Br and I; C = S, Se and Te). Their Tcvalues were predicted from over 100 K to near 500 K with Monte Carlo simulations using an anisotropic Heisenberg model. Eight members among them show semiconducting bandgaps varying from roughly 0.23 to 1.85 eV. These semiconducting monolayers also show extremely large anisotropy, i.e. ～10~1 for effective masses and ～10~2 for carrier mobilities, along the two in-plane lattice directions of these layers. Additional orbital anisotropy leads to a spin-locked linear dichroism, in different from previously known circular and linear dichroisms in layered materials.Together with the mobility anisotropy, it offers a spin-, dichroism-and mobility-anisotropy locking.These results manifest the potential of this 2D family for both fundamental research and high performance spin-dependent electronic and optoelectronic devices.

关键词： Two-dimentional materials First-principles calculation Strong mobility anisotropy Spin-locked linear dichroism High-temperature ferromagnets Direct bandgap semic on ductor

Challenges and perspectives for structural biology of IncRNAs-the example of the Xist IncRNA A-repeats

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Journal of Molecular Cell Biology 2019年第10期11卷 845-859页

作者： Alisha NJones Michael Sattler Institute of Structural Biology Helmholtz Zentrum MunchenNeuherberg85764Germany Center for Integrated Protein Scienee Munich and Bavarian NMR Center at Department of Chemistry Technical University of MunichGarching85747Germany

Following the discovery of numerous long non-coding RNA(IncRNA)transcripts in the human genome,their important roles in biology and human disease are emerging.Recent progress in experimental methods has enabled the identification of structural features of IncRNAs.However,determining high-resolution structures is challenging as IncRNAs are expected to be dynamic and adopt multiple conformations,which may be modulated by interaction with protein binding partners.The X-inactive specific transcript(Xist)is necessary for X inactivation during dosage compensation in female placental mammals and one of the beststudied IncRNAs.Recent progress has provided new insights into the domain organization,molecular features,and RNA binding proteins that interact with distinct regions of Xist.The A-repeats located at the 5'end of the transcript are of particular interest as they are essential for mediating silencing ofthe inactive X chromosome.Here,we discuss recent progress with elucidating structural features of the Xist IncRNA,focusing on the A-repeats.We discuss the experimental and computational approaches employed that have led to distinct structural models,likely reflecting the intrinsic dynamics of this RNA.The presence of multiple dynamic conformations may also play an important role in the formation ofthe associated RNPs,thus influencing the molecular mechanism underlying the biological function of the Xist A-repeats.We propose that integrative approaches that combine biochemical experiments and high-resolution structural biology in vitro with chemical probing and functional studies in vivo are required to unravel the molecular mechanisms of IncRNAs.

关键词： In cRNA structural biology Xist chemical pro bing enzymatic footpri nting computational structure predicti on

Changes in climate regimes over China based on a high-resolution dataset

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Science Bulletin 2019年第6期64卷 377-379页

作者： Wei Huang Jingjing Yan Chang Liu Tingting Xie Key Laboratory of Western China’s Environmental Systems (Ministry of Education) College of Earth and Environmental Sciences Lanzhou University Central Asia Center for Atmospheric Science Research China Meteorological Administration Department of Geosciences University of Arkansas

During the 20th century the global climate has been shifted towards warmer and drier regimes, mainly due to anthropogenic warming [1,2]. Climate changes can notably disrupt the environment and ecosystems. To evaluate the impacts of climate change on ecoregions, the Kdppen-Trewartha (K-T) climate classification [3] is widely used because it was constructed on the basis of surface vegetation. The K-T classification system combines temperature, precipitation, and their seasonality into a single metric. Six major climate types and several sub-climate types are defined (A: tropical, B: dry, C: subtropical, D: temperate, E: subpolar, F: polar). Each K-T climate type is consistent with certain prevalent plant species. Definitions and criteria of K-T climate types were outlined by Feng et al.[4].

关键词： climate has been shifted change on ecoregions climate types

Specific function and modulation of teleost monocytes/macrophages: polarization and phagocytosis

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Zoological Research 2019年第3期40卷 146-150页

作者： Xin-Jiang Lu Jiong Chen Laboratory of Biochemistry and Molecular Biology School of Marine Sciences Ningbo University Ningbo Zhejiang 315211 China Key Laboratory of Applied Marine Biotechnology of Ministry of Education Ningbo University Ningbo Zhejiang 315211 China

Macrophages exist in most tissues and play a variety of functions in vertebrates.Teleost fish species are found in most aquatic environments throughout the world and are quite diverse for a group of vertebrate animals.Due to whole genome duplication and en vironme ntal adaptati on,teleost monocytes/macrophages possess a variety of different functions and modulations compared with those of mammals.A deeper understanding of teleost monocytes/macrophages in the immune system will not only help develop teleost-specific methods of disease prevention but will also help improve our understanding of the various immune mechanisms in mammals.In this review,we summarize the differences in polarizati on and phagocytosis of teleost and mammalian macrophages to improve our understanding of the various immune mechanisms in vertebrates.

关键词： Teleost Monocytes/Macrophages Phagocytosis Cytokine producti on Comparative immunology

Optimizational production of phenyllactic acid by a Lactobacillus buchneri strain via uniform design with overlay sampling methodology

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Chinese Journal of Chemical Engineering 2019年第2期27卷 418-425页

作者： Jintao Guan Chaofei Han Yixin Guan Songhong Zhang Junxian Yun Shanjing Yao College of Chemical and Biological Engineering Zhejiang University State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology College of Chemical Engineering Zhejiang University of Technology

A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of grampositive and gram-negative bacteria and some fungi. The growth performance of this strain in the de Man, Rogosa and Sharpe(MRS) medium, the production of metabolites of valuable organic acids, and the biosynthesis of PLA using this strain as the whole-cell biocatalyst and phenylpyruvic acid(PPA) as the precursor, were investigated experimentally. The uniform design method with overlay sampling was developed for the optimization of the biotransformation conditions. The results showed that although it produced naturally lactic acid with the maximum concentration of 1.84 g·L^(-1) and PLA with the concentration of 0.015 g·L^(-1) after 66 to 72 h cultivation in MRS broth by fermentation, the present strain displayed an effective utilization ability by transforming PPA to PLA. By the uniform design method with overlay sampling for the design and optimization of transformation conditions, a maximum yield of 10.93 g·L^(-1) PLA with the mole conversion ratio of 83.07% from PPA to PLA was achieved under the optimized condition, i.e., 20 g·L^(-1) glucose, 270 g·L^(-1) cells, 13 g·L^(-1) PPA, pH 8.0 and the reaction time of 15 h, indicating that Lactobacillus buchneri GBS3 was an interesting strain for the biosynthesis of PLA via the microbial transformation. The prediction of PLA yield under different conditions was achieved successfully based on the limited information of only a small number of experiments by the uniform design with overlay sampling. Therefore, the present methodology is effective and helpful for the optimization of the biosynthesis processes of PLA.

关键词： Phenyllactic Acid Biotransformati on Lactobacillus Buchneri Uniform Design Overlap Sampling

Integrating time progression in ecoimmunology studies: beyond immune response intensity

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Current Zoology 2019年第2期65卷 205-212页

作者： Francisco Javier ZAMORA-CAMACHO Department of Biological Sciences Dartmouth College Hanover New Hampshire USA Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (MNCN) Spanish National Research Council (CSIC) Madrid Spain

Habitat alterations in agroecosystems may damage amphibian immune capacity. As agroecosystem extension is increasing worldwide, broader-context knowledge on the effects of agroecosystem stressful conditions on amphibian immune capacity is crucial for understanding and management of amphibian global declines. However, most studies on ecoimmunology assume synchronal amonggroup immune-response peaks, and focus on immune response after standardized time lapses, neglecting its progress!on. Herein, I compared inflamatory response short-term progression of agro ecosystem and n atural-habitat female and male n atterjack toads Epi da lea calamita, by measuri ng swelling response, once per hour, 6 h following an artificial immune challenge with innocuous antigen phytohemagglutinin. I also compared maximum magnitude of swelling response, irrespective of the moment when it was reached. Habitat differences arose only 3 h after challenge, when naturalhabitat toads showed greater swelling response. Maximum magnitude of swelling response was similar in toads from both habitats. However, agroecosystem toads showed a delayed swelling response as compared with natural-habitat conspecifics, probably as a consequenee of agroecosystem stressful conditions. Such a delay suggests a weaker immune capacity, and consequently impaired anti-pathogen performance. Regarding sex, swelling response magnitude did not differ between males and females. Female swelling response peaked earlier, but that of males was more sustai ned in time, which con tradicts general across-taxa fin dings that males show impaired immune response. Interestingly, results suggest that measuring swelling response only after some standardized period following stimulation may be a simplistic approach and produce unrealistic results. Consequently, studies on ecoimmunology should implement swelling response progression in order to produce unbiased science.

关键词： agroecosystem amphibian immunocompetence natural habitat immune response progressi on

Freezing on demand: A new concept for mine safety and energy savings in wet underground mines

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International Journal of Mining Science and Technology 2019年第4期29卷 621-627页

作者： Mahmoud A.Alzoubi Ahmad Zueter Aurelien Nie-Rouquette Agus P.Sasmito Department of Mining and Materials Engineering McGill University

The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation areas.This mode of operation requires a massive amount of energy to sustain the thickness of the frozen body.Therefore,it is of great interest to propose new concepts to reduce energy consumption while providing sufficient structural stability and safe operation.This paper discusses the principle of the freezing on demand(FoD)by means of experiment and mathematical model.A lab-scale rig that mimics the AGF process is conceived and developed.The setup is equipped with more than 80 thermocouples,flow-meters,and advanced instrumentation system to analyze the performance of the AGF process under the FoD concept.A mathematical model has been derived,validated,and utilized to simulate the transient FoD concept.The results suggest that the overall energy saving notably depends on the coolant’s temperature;the energy saving increases while decreasing the coolant inlet temperature.Moreover,applying the FoD concept in an AGF system leads to a significant drop in energy consumption.

关键词： Artificial ground freezing Freezing on demand Energy saving Conjugate heat transfer Porous media