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Global Analysis of Direct Targets of Secondary Wall NAC Master Switches in Arabidopsis

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Molecular Plant 2010年第6期3卷 1087-1103页

作者： ruiqin zhong Chanhui Lee Zheng-Hua Ye Department of Plant Biology University of Georgia Athens GA 30602 USA

We report the genome-wide analysis of direct target genes of SND1 and VND7, two Arabidopsis thaliana NAC domain transcription factors that are master regulators of secondary wall biosynthesis in fibers and vessels, respectively. Systematic mapping of the SND1 binding sequence using electrophoretic mobility shift assay and transactivation analysis demonstrated that SND1 together with other secondary wall NACs （SWNs）, including VND6, VND7, NST1, and NST2, bind to an imperfect palindromic 19-bp consensus sequence designated as secondary wall NAC binding element （SNBE）, （T/A）NN（C/T）（TICIG）TNNNNNNNA（AIC）GN（AJCIT）（A/T）, in the promoters of their direct targets. Genome-wide analysis of direct targets of SND1 and VND7 revealed that they directly activate the expression of not only downstream transcription factors, but also a number of non-transcription factor genes involved in secondary wall biosynthesis, cell wall modification, and programmed cell death, the promoters of which all contain multiple SNBE sites. SND1 and VND7 directly regulate the expression of a set of common targets but each of them also preferentially induces a distinct set of direct targets, which is likely attributed to their differential activation strength toward SNBE sites. Complementation study showed that the SWNs were able to rescue the secondary wall defect in the sndl nstl mutant, indicating that they are functionally interchangeable. Together, our results provide important insight into the complex transcriptional program and the evolutionary mechanism underlying secondary wall biosynthesis, cell wall modification, and programmed cell death in secondary wall-containing cell types.

关键词： Arabidopsis secondary cell walls NAC transcription factor transcriptional regulation.

Molecular Dissection of Xylan Biosynthesis during Wood Formation in Poplar

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Molecular Plant 2011年第4期4卷 730-747页

作者： Chanhui Lee Quincy Teng ruiqin zhong Zheng-Hua Ye Department of Plant Biology University of Georgia Athens GA 30602 USA National Exposure Research Laboratory US Environmental Protection Agency Athens GA 30605 USA

Xylan, being the second most abundant polysaccharide in dicot wood, is considered to be one of the factors contributing to wood biomass recalcitrance for biofuel production. To better utilize wood as biofuel feedstock, it is crucial to functionally characterize all the genes involved in xylan biosynthesis during wood formation. In this report, we investigated roles of poplar families GT43 and GT8 glycosyltransferases in xylan biosynthesis during wood formation. There exist seven GT43 genes in the genome of poplar （Populus trichocarpa）, five of which, namely PtrGT43A, PtrGT43B, PtrGT43C, PtrGT43D, and PtrGT43E, were shown to be highly expressed in the developing wood and their encoded proteins were localized in the Golgi. Comprehensive genetic complementation coupled with chemical analyses demonstrated that overexpression of PtrGT43A/B/E but not PtrGT43C/D was able to rescue the xylan defects conferred by the Arabidopsis irx9 mutant, whereas overexpression of PtrGT43C/D but not PtrGT43A/B/E led to a complementation of the xylan defects in the Arabidopsis irx14 mutant. The essential roles of poplar GT43 members in xylan biosynthesis was further substantiated by RNAi down-regulation of GT43B in the hybrid poplar （Populus alba x tremula） leading to reductions in wall thickness and xylan content in wood, and an elevation in the abundance of the xylan reducing end sequence. Wood digestibility analysis revealed that cellulase digestion released more glucose from the wood of poplar GT43B RNAi lines than the control wood, indicating a decrease in wood biomass recalcitrance. Furthermore, RNAi down-regulation of another poplar wood-associated glycosyltransferase, PoGTSD, was shown to cause decreases in wall thickness and xylan content as well as in the abundance of the xylan reducing end sequence. Together, these findings demonstrate that the poplar GT43 members form two functionally non-redundant groups, namely PtrGT43A/B/E as functional orthologs of Arabidopsis IRX9 and PtrG

关键词： Glycosyltransferase GT8 family GT43 family poplar wood formation xylan.

Disruption of Cortical Microtubules by Overexpression of Green Fluorescent Protein-Tagged a-Tubulin 6 Causes a Marked Reduction in Cell Wall Synthesis

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Journal of Integrative Plant Biology 2006年第1期48卷 85-98页

作者： David H. Burk ruiqin zhong W. Herbert Morrison III Zheng-Hua Ye Department of Plant Biology University of Georgia Athens Georgia 30602 USA Richard B. Russell Agriculture Research Center U.S. Department of Agriculture Agricultural Research Service Athens Georgia 30604 USA

It has been known that the transverse orientation of cortical microtubules （MTs） along the elongation axis is essential for normal cell morphogenesis, but whether cortical MTs are essential for normal cell wall synthesis is still not clear. In the present study, we have investigated whether cortical MTs affect cell wall synthesis by direct alteration of the cortical MT organization in Arabidopsis thaliana. Disruption of the cortical MT organization by expression of an excess amount of green fluorescent protein-tagged a-tubulin 6 （GFP-TUA6） in transgenic Arabidopsis plants was found to cause a marked reduction in cell wall thickness and a de- crease in the cell wall sugars glucose and xylose. Concomitantly, the stem strength of the GFP-TUA6 overexpressors was markedly reduced compared with the wild type. In addition, expression of excess GFP- TUA6 results in an alteration in cell morphogenesis and a severe effect on plant growth and development. Together, these results suggest that the proper organization of cortical MTs is essential for the normal synthesis of plant cell walls.

关键词： Arabidopsis thaliana cell elongation cell wall synthesis cortical microtubules microtubule organization.

水泥/石灰和土壤固化剂复合改良膨胀土试验研究

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市政技术 2024年第1期42卷 192-199,205页

作者：钟瑞芹王杰鲁赟郭腾孙博通薛立军北京市政建设集团有限责任公司北京100089 北京高新市政工程科技有限公司北京100195 北京市公联公路联络线有限责任公司北京100161

采用水泥/石灰和BJ-W土壤固化剂对安徽地区膨胀土进行了改良试验研究。依据液限、塑限和自由膨胀率试验初步选定改良膨胀土的配合比范围,并通过胀缩总率、无侧限抗压强度和稳定性试验,进一步分析了改良膨胀土的性能变化规律。试验结果表... 详细信息

采用水泥/石灰和BJ-W土壤固化剂对安徽地区膨胀土进行了改良试验研究。依据液限、塑限和自由膨胀率试验初步选定改良膨胀土的配合比范围,并通过胀缩总率、无侧限抗压强度和稳定性试验,进一步分析了改良膨胀土的性能变化规律。试验结果表明,掺入水泥/石灰和BJ-W土壤固化剂复合改良中、弱膨胀土时,液限逐渐减小,塑限逐渐增大,自由膨胀率降低到40%以下,且胀缩总率低于0.7%;无侧限抗压强度和稳定性试验中,改良膨胀土的强度和水稳系数(>80%)显著增加,且经过5次干湿循环后,改良膨胀土的强度衰减率小于20%,膨胀土的反复胀缩特性显著改善。综合考虑改良膨胀土的胀缩和强度特性,采用水泥和BJ-W土壤固化剂复合改良膨胀土效果最佳,中膨胀土最优配合比为7%水泥和0.02%BJ-W土壤固化剂,弱膨胀土最优配合比为6%水泥和0.02%BJ-W土壤固化剂。

关键词：水泥/石灰土壤固化剂改良膨胀土

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Atomic Fe-N4 sites on electrospun hierarchical porous carbon nanofibers as an efficient electrocatalyst for oxygen reduction reaction

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Chinese Chemical Letters 2020年第6期31卷 1588-1592页

作者： ruiqin zhong Chenxu Zhi Yingxiao Wu Zibin Liang Hassina Tabassum Hao Zhang Tianjie Qiu Song Gao Jinming Shi Ruqiang Zou State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials Department of Materials Science and EngineeringCollege of EngineeringPeking UniversityBeijing J00871China

Porous carbon materials doped with atomically dispersed metal sites(ADMSs)are promising electrocatalysts for oxygen reduction reaction(ORR)*** this work,we fabricated hierarchical porous nitrogen-doped carbon nanofibers with atomically dispersed Fe-N4 sites by carbonization of electrospinning iron-based metal-organic frameworks(MOFs)/polyacrylonitrile nanofibers for ORR ***,the re sultant carbon nanofibers with atomically dispersed FeN4 sites exhibit extraordinary electrochemical performance with an onset potential of 0.994 V and a halfwave potential of 0.876 V in alkaline electrolyte,comparable to the benchmark commercial Pt/C *** high catalytic performance is originated from the unique hierarchically porous 1 D carbon structure and abundant highly active atomically dispersed Fe-N4 sites.

关键词： Atomically dispersed metal sites Metal-organic frameworks Electrospinning Oxygen reduction reaction Electrocatalysis

Enhancing hydrophobicity via core-shell metal organic frameworks for high-humidity flue gas CO_(2) capture

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Chinese Journal of Chemical Engineering 2023年第9期61卷 82-89页

作者： Yinji Wan Dekai Kong Feng Xiong Tianjie Qiu Song Gao Qiuning Zhang Yefan Miao Mulin Qin Shengqiang Wu Yonggang Wang ruiqin zhong Ruqiang Zou State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials School of Materials Science and EngineeringPeking UniversityBeijing 100871China

Developing metal-organic framework(MOF)materials with the moisture-resistant feature is highly desirable for CO_(2)capture from highly humid flue *** this work,a new core-shell MOF@MOF composite using Mg-MOF-74 with high CO_(2)capture capacity as a functional core and hydrophobic zeolitic imidazolate framework-8(ZIF-8)as a protective shell is fabricated by the epitaxial growth *** results show that the CO_(2)adsorption performance of the core-shell structured Mg-MOF-74@ZIF-8 composites from water-containing flue gas is enhanced along with their improved *** dynamic breakthrough results show that the Mg-MOF-74@ZIF-8 with three assembled layers(Mg-MOF-74@ZIF-8-3)can capture 3.56 mmol-g^(-1)CO_(2)from wet CO_(2)/N_(2)(VCO_(2):V_(N_(2))=15:85)mixtures,which outperforms Mg-MOF-74(0.37 mmol·g^(-1))and most of the reported physisorbents.

关键词： Core-shell Mg-MOF-74@ZIF-8 CO_(2)capture Hydrophobic effect

UiO-66系列材料的制备及其吸附分离CO2/CO性能研究

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化工新型材料 2020年第7期48卷 221-224页

作者：黄兴钟瑞琴内江师范学院内江641100 中国石油大学(北京)重质油国家重点实验室北京102249

在对苯二甲酸(H2BDC)苯环上引入不同的取代基,通过与氯化锆(ZrCl4)和冰乙酸在N,N-二甲基甲酰胺(DMF)中进行溶剂热反应合成UiO-66系列金属有机骨架材料,测试材料对合成气中CO2,CO的吸附性能。结果表明UiO-66-NH2对CO2吸附量最高,为100.14... 详细信息

在对苯二甲酸(H2BDC)苯环上引入不同的取代基,通过与氯化锆(ZrCl4)和冰乙酸在N,N-二甲基甲酰胺(DMF)中进行溶剂热反应合成UiO-66系列金属有机骨架材料,测试材料对合成气中CO2,CO的吸附性能。结果表明UiO-66-NH2对CO2吸附量最高,为100.14cm3/g,对CO吸附量为17.69cm3/g,在CO2/CO体系中对CO2有较高的分离性能。

关键词：金属有机骨架材料二氧化碳吸附与分离

面向自动化专业的《化工原理》课程教学改革与实践

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山东化工 2020年第10期49卷 203-204页

作者：钟瑞琴中国石油大学(北京)化学工程与环境学院北京102249

通过对中国石油大学(北京)信息科学与工程学院自动化系三个年级《化工原理》课程的教学中面临的问题进行了分析,结合《化工原理》课程的特点和我校自动化专业本科生培养需求,对课程进行了教学改革与实践,也为高校非化工专业的《化工原... 详细信息

通过对中国石油大学(北京)信息科学与工程学院自动化系三个年级《化工原理》课程的教学中面临的问题进行了分析,结合《化工原理》课程的特点和我校自动化专业本科生培养需求,对课程进行了教学改革与实践,也为高校非化工专业的《化工原理》教学的方法探索提供了参考。

关键词：化工原理自动化专业教学改革

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隧道渗漏水渗流场响应及注浆治理效果分析

市政技术 2023年第10期41卷 210-217页

作者：陈继宏郭腾王杰钟瑞芹北京市市政六建设工程有限公司北京100023 北京市政建设集团有限责任公司北京100089

为深刻揭示隧道结构劣化、注浆空洞以及注浆治理等因素与渗漏水病害之间的内在作用关系,利用有限差分软件FLAC 3D和流-固耦合分析方法,对基于隧道结构劣化、结构背后注浆空洞等工况引发的渗漏水病害产生的围岩渗流场及渗漏水注浆治理效... 详细信息

为深刻揭示隧道结构劣化、注浆空洞以及注浆治理等因素与渗漏水病害之间的内在作用关系,利用有限差分软件FLAC 3D和流-固耦合分析方法,对基于隧道结构劣化、结构背后注浆空洞等工况引发的渗漏水病害产生的围岩渗流场及渗漏水注浆治理效果进行了系统分析,并结合实际工程进行了验证。结果表明,隧道结构劣化发展对拱顶、拱肩和拱腰处的围岩孔隙水压力造成了较大幅度的折减,结构背后注浆空洞使得围岩孔隙水压力折减范围增大,且拱底处注浆空洞对围岩孔隙水压力折减幅度影响最为显著。此外,结构劣化发展和注浆空洞可能会对隧道二衬结构造成拉裂破坏,其中结构劣化发展和拱底处的注浆空洞对二衬整体均衡受力影响最为明显。注浆法可从本质上改善围岩渗流场分布和结构受力,该研究成果可为不同位置的注浆空洞型渗漏水病害提供相应的注浆治理建议。针对地下结构渗漏水病害,自主研发了治理性能更为优异的新型注浆材料,在拱顶和拱肩空洞型渗漏水注浆治理中,相比于常规注浆材料,新型注浆材料可使空洞处围岩孔隙水压力分别提高10.5%和9.2%以上,具有更好的治理效果。

关键词：渗漏水流-固耦合围岩渗流场注浆治理