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Identification of the Regulator of G-Protein Signaling Protein Responsive to Plant Hormones and Abiotic Stresses in Brassica napus

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Journal of Integrative Agriculture 2014年第12期13卷 2634-2644页

作者： CHEN Yun zhu Xia zhu Xiao-bin YU yi-fan GE Hui-min GAO Yong LIANG Jian-sheng College of Bioscience and Biotechnology Yangzhou University

Regulator of G protein signaling proteins （RGS） accelerate the rate of GTP hydrolysis by Gαproteins, thus acting as negative regulators of G-protein signaling. Studies on Arabidopsis and soybean have proven that RGS proteins are physiologically important in plants and contribute to the signaling pathways regulated by different stimuli. Brassica napus is an important agriculturally relevant plant, the wildly planted oilseed rape in the world, which possesses an identiifed Gα, Gβand Gγsubunits. In the present study, we identiifed and characterized a Brassica napus RGS gene, BnRGS1, which contained an open reading frame of 1 380 bp encoding a putative 52.6 kDa polypeptide of 459 amino acids, within seven putative transmembrane domains in the N-terminal and RGS box in the C-terminal. BnRGS1 is located on the membrane in onion epidermal cells and tobacco leaves, and interacts with BnGA1 in the mating-based split-ubiquitin system. The expression levels of BnRGS1 were quite different in different tissues and developmental stages, and induced by abscisic acid （ABA） and indole-3-acetic acid （IAA）. The effects of gibberellin （GA3） and brassinolide （BR） on the expression of BnRGS1 were irregular under the concentrations tested. Moreover, the transcript level of BnRGS1 was also induced by polyethylene glycol （PEG）, whereas remained little changed by 200 mmol L-1 NaCl. These results suggested that the BnRGS1 may be involved in B. napus response to plant hormone signaling and abiotic stresses.

关键词： BnRGS1 expression plant hormone abiotic stress

Early Crystallized Titanomagnetite from Evolved Magmas and Magma Recharge in the Mesoproterozoic zhuqing Oxide-Bearing Gabbroic Intrusions,Sichuan,SW China

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 486-499页

作者： fan Hongpeng zhu Weiguang State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081GuizhouChina

The ca. 1.5 Ga mafic intrusions in the zhuqing area, predominantly composed of alkaline gabbroic rocks in the Kangdian region of SW China, occur as dykes or irregular small intrusions hosting Fe–Ti–V mineralization. All of the intrusions that intrude the dolomite or shales of the Mesoproterozoic Heishan Formation of the Huili Group are composed of three cyclic units from the base upward： a marginal cyclic unit, a lower cyclic unit and an upper cyclic unit. The Fe–Ti–V oxide ore bodies are hosted in the lower and upper cyclic units. The textural relationships between minerals in the intrusions suggest that titanomagnetite formed earlier than silicate grains because euhedral magnetite and ilmenite grains were enclosed in clinopyroxene and plagioclase. Both the magnetitess–ilmenitess intergrowths due to subsolidus oxidation–exsolutions and the relative higher V distribution coefficient between magnetite and silicate melts in the gabbros from the zhuqing area are different from those of other typical Fe–Ti bearing mafic rocks, suggesting that the oxygen fugacity was low in the gabbric rocks from the zhuqing area. This finding was further confirmed by calculations based on the compositions of magnetite and ilmenite pairs. The clinopyroxene, magnetite and ilmenite in the intrusions from the zhuqing area had considerably lower Mg O than those of other typical Fe–Ti oxide-rich complexes, suggesting that the titanomagnetite from the intrusion may have crystallized at a relatively late stage of evolution from a more evolved magma. Titanomagnetite first fractionally crystallized and subsequently settled in the lower parts of the magma chamber, where it concentrated and formed Fe–Ti–V oxide ore layers at the bases of the lower and upper cycles. Moreover, the occurrence of multiple Fe-Ti oxide layers alternating with Fe-Ti oxide-bearing silicate layers suggests that multiple pulses of magma were involved in the formation of the intrusions and related Fe-Ti-V oxide deposits in th

关键词： Fe–Ti oxide mineral chemistry patrogenesis Mesoproterozoic zhuqing oxide ore deposits Kangdian region SW china East margin of Tibetan Plateau Proto-Tethys

Sufficient dimension reduction in the presence of controlling variables

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Science China Mathematics 2022年第9期65卷 1975-1996页

作者： Guoliang fan Liping zhu School of Economics and Management Shanghai Maritime UniversityShanghai 201306China Center for Applied Statistics and Institute of Statistics and Big Data Renmin University of ChinaBeijing 100872China Institute of Statistics and Big Data Zhejiang Gongshang UniversityHangzhou 310018China

We are concerned with partial dimension reduction for the conditional mean function in the presence of controlling *** suggest a profile least squares approach to perform partial dimension reduction for a general class of semi-parametric *** asymptotic properties of the resulting estimates for the central partial mean subspace and the mean function are *** addition,a Wald-type test is proposed to evaluate a linear hypothesis of the central partial mean subspace,and a generalized likelihood ratio test is constructed to check whether the nonparametric mean function has a specific parametric *** tests can be used to evaluate whether there exist interactions between the covariates and the controlling variables,and if any,in what form.A Bayesian information criterion(BIC)-type criterion is applied to determine the structural dimension of the central partial mean *** consistency is also *** studies through simulations and real data examples are conducted to demonstrate the power and utility of the proposed semi-parametric approaches.

关键词： central partial mean subspace controlling variable hypothesis test semi-parametric regression sufficient dimension reduction

Insights into bacterial protein glycosylation in human microbiota

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Science China(Life Sciences) 2016年第1期59卷 11-18页

作者： fan zhu Hui Wu Departments of Microbiology and Pediatric Dentistry Schools of Dentistry and Medicine University of Alabama at Birmingham

The study of human microbiota is an emerging research topic. The past efforts have mainly centered on studying the composition and genomic landscape of bacterial species within the targeted communities. The interaction between bacteria and hosts is the pivotal event in the initiation and progression of infectious diseases. There is a great need to identify and characterize the molecules that mediate the bacteria-host interaction. Bacterial surface exposed proteins play an important role in the bacteria-host interaction. Numerous surface proteins are glycosylated, and the glycosylation is crucial for their function in mediating the bacterial interaction with hosts. Here we present an overview of surface glycoproteins from bacteria that inhabit three major mucosal environments across human body: oral, gut and skin. We describe the important enzymes involved in the process of protein glycosylation, and discuss how the process impacts the bacteria-host interaction. Emerging molecular details underlying glycosylation of bacterial surface proteins may lead to new opportunities for designing anti-infective small molecules, and developing novel vaccines in order to treat or prevent bacterial infection.

关键词： microbiota surface glycoprotein glycosylation bacteria-host interaction glycosyltransferase

Effects of Ce on catalytic combustion of methane over Pd-Pt/Al_2O_3 catalyst

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Journal of Environmental Sciences 2012年第3期24卷 507-511页

作者： Xing fan fan Wang Tianle zhu Hong He School of Chemistry and Environment Beihang UniversityBeijing 100191China College of Environmental and Energy Engineering Beijing University of TechnologyBeifing 100124China

Activity and stability of 1%Pd-0.2%Pt/Al2O3 and 1%Pd-0.2%Pt/0.6%Ce/Al2O3 catalysts prepared by impregnation method for catalytic combustion of methane in air were investigated. The catalysts before and after reaction were characterized by BET, CO chemisorption, XRD and XPS techniques. Results showed that the presence of Ce significantly increased the activity and thermal stability of the Pd-Pt/Al2O3 catalyst towards methane combustion, which could be attributed to more highly-dispersed active PdO particles over the Pd-Pt/Ce/Al2O3 catalyst surface as well as the retarded sintering of PdO and the maintained oxidized state of surface Pd during the combustion process in the presence of Ce.

关键词： catalytic combustion methane Pd-Pt/Ce/Al2O3 catalyst stability metal dispersion

Large-scale Dynamics of Line-driven Winds with the Re-radiation Effect

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Research in Astronomy and Astrophysics 2023年第12期23卷 105-117页

作者： yi zhu Jinsen Xie School of Nuclear Science and Technology University of South ChinaHengyang 421001China

Previous simulations studying winds only focus on the line force due to photons from central active galactic *** properties of the winds will be when including the re-radiation force due to the scattered and reprocessed photons(i.e.,the re-radiation effect)?We perform simulations to study the large-scale dynamics of accretion disk winds driven by radiation line force and re-radiation *** the fiducial run,we find that the re-radiation force drives stronger outflows during the early *** the flows get into the steadiness,the UV radiation due to spectral lines dominates total radiation and the re-radiation effect could be *** opening angle of winds narrows as the initial gas density *** larger the gas density is,the stronger the re-radiation effect will *** MBH=10^(6)M_(⊙),ε=0.3,the outflows do become much stronger with the re-radiation effect and the winds still cannot escape from gravitational *** find that the detection probability of ultra-fast outflows and the properties of the winds are both consistent with the observations.

关键词： accretion-accretion disks-black hole physics-galaxies nuclei-stars winds-outflows

Analysis of relative error in detection caused by signal-induced noise in Na lidar system

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Science China Earth Sciences 2018年第1期61卷 109-118页

作者： ZHANG YunPeng yi fan KONG Wei School of Electronic Information Wuhan University

Signal-induced noise(SIN) in a photomultiplier tube(PMT) introduces bias into the Na density results that are retrieved from the backscattered signals of Na resonance fluorescence lidar systems. The response characteristics of a PMT when stimulated by a series of light pulses with a fixed width of 1 μs are therefore used to develop a precise SIN model to estimate the relative error caused by SIN. Unless the strong signals that are returned from the lower atmosphere are excluded, the measured density results are always smaller than the actual values, and the resulting relative error may be 50% or more. Three potential solutions to reduce the SIN were quantified for comparison, including use of a chopper system, use of a gated circuit, and separation of the laser beam and the telescope receiver. When optimized parameters are used for these technologies, the relative error can then be reduced to less than 2%.

关键词： Lidar Signal-induced noise Photomultiplier tube

Recent advances in DNAzyme-based gene silencing

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Science China Chemistry 2017年第5期60卷 591-601页

作者： Huanhuan fan Xiaobing Zhang yi Lu Molecular Science and Biomedicine Laboratory State Key Laboratory of Chemo/Bio-Sensing and Chemometrics Collaborative Innovation Center for Chemistry and Molecular MedicineCollege of Chemistry and Chemical Engineering College of Biology Hunan University Changsha 410082 China Department of Chemistry Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA

DNAzymes, generated through in vitro selection processes, are single-stranded DNA catalysts that can catalyze a wide variety of reactions, such as RNA or DNA cleavage and ligation or DNA phosphorylation. Based on specific cofactor dependence and potent catalytic ability, DNAzymes have been extensively used to develop highly sensitive and specific sensing platforms for metal ions,small molecules, and biomacromolecules. However, in spite of their multiple strong enzymatic turnover properties, few reports have addressed the potential application of RNA-cleaving DNAzymes as therapeutic gene-silencing agents. The main challenges are being met with low efficiency of cellular uptake, instability and the lack of sufficient cofactors for cellular or in vivo study, which have limited the development of DNAzymes for clinical application. In recent years, substantial progress has been made to enhance the delivery efficiency and stability of DNAzymes by developing variety of methods. Smart metal oxide nanomaterials have also been used to meet the requirement of cofactors in situ. This review focuses on the gene silencing application of DNAzymes as well as their physicochemical properties. Methods of increasing the efficacy of DNAzymes in gene therapy are also discussed: delivery systems to enhance the cellular uptake, modifications to enhance the stability and smart systems to generate sufficient cofactors in situ. Finally, some future trends and perspectives in these research areas are outlined.

关键词： DNAzymes gene-silencing delivery stability cofactors

Modeling the dynamics of information propagation in the temporal and spatial environment

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Communications in Theoretical Physics 2023年第9期75卷 22-35页

作者： yi Zhang Linhe zhu School of Mathematical Sciences Jiangsu UniversityZhenjiang212013China

In this paper, we try to establish a non-smooth susceptible–infected–recovered(SIR) rumor propagation model based on time and space dimensions. First of all, we prove the existence and uniqueness of the solution. Secondly, we divide the system into two parts and discuss the existence of equilibrium points for each of them. For the left part, we define R_(0) to study the relationship between R_(0) and the existence of equilibrium points. For the right part, we classify many different cases by discussing the coefficients of the equilibrium point equation. Then, on this basis, we perform a bifurcation analysis of the non-spatial system and find conditions that lead to the existence of saddle-node bifurcation. Further, we consider the effect of diffusion. We specifically analyze the stability of equilibrium points. In addition, we analyze the Turing instability and Hopf bifurcation occurring at some equilibrium points. According to the Lyapunov number, we also determine the direction of the bifurcation. When I = I_(c), we discuss conditions for the existence of discontinuous Hopf bifurcation. Finally, through numerical simulations and combined with the practical meaning of the parameters, we prove the correctness of the previous theoretical theorem.

关键词： non-smooth system rumor propagation Turing instability Hopf bifurcation