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RNA-dependent pseudouridylation catalyzed by box H/ACA RNPs

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Frontiers in Biology 2018年第1期13卷 1-10页

作者： Meemanage D. De Zoysa yi-tao yu University of Rochester Medical Center Department of Biochemistry and Biophysics Center for RNA Biology 601 Elmwood AvenueRochester NY14642 USA

BACKGROUND： Pseudouridine （Ψ） is the most abundant post-transcriptionally modified nucleotide found in RNA. ~ is clustered in functionally important and evolutionary conserved regions of RNAs in all three domains of life. Pseudouridylation is catalyzed by two distinct mechanisms： an RNA-independent and an RNA-dependent mechanism. The former involves a group of stand-alone protein enzymes, and the latter involves a family of complex enzymes called box H/ACA RNPs, each of which consists of one RNA （box H/ACA RNA） and a set of four core proteins. Over the years, the mechanism of RNA- dependent pseudouridylation has been extensively studied. The crystal structures of partial and complete box H/ACA RNP have been solved. However, the detailed picture of RNA-dependent pseudouridylation is still not entirely clear. OBJECTIVE： In this work, we review what is known about box H/ACA RNP and the mechanism by which box H/ACA RNP catalyzes RNA-dependent pseudouridylation. We also discuss some examples of the dual nature and redundancy of box H/ ACA RNPs that deviate from the usual mechanism. METHODS： A methodical literature search was performed using the Pubmed central search engine and International Digital Publishing Forum （EPUB） using the following keywords：＂pseudouridylation,＂＂pseudouridine,＂ and ＂box H/ACA RNP.＂ The necessary information was extracted and cited. RESULTS： A detailed introduction is made including the discovery, mechanism and crystal structure of box H/ACA RNP. Three sequence/structural requirements for box H/ACA RNA-guided pseudouridylation are discussed and the exceptions to those rules are explored. CONCLUSION： Over the years, box H/ACA RNP-catalyzed pseudouridylation has been extensively studied, generating fruitful results. However, a detailed picture regarding the mechanism of this reaction is still to be deciphered. More work is needed to fully understand box H/ACA RNP-catalyzed pseudouridylation.

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Synthesis and characterization of α-N,N-dihydroxyethylaminopropyl-ω-butylpolydimethylsiloxanes

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Chinese Chemical Letters 2008年第1期19卷 47-50页

作者： yi tao yu Qing Si Zhang Meng Zhang Hai Feng Sun School of Chemical Engineering Shandong Institute of Light Industry Jinan 250100 China School of Chemistry and Material Southern Yangtz University Wuxi 214122 China

A series of α-N,N-dihydroxyethylaminopropyl-ω-butylpolydimethylsiloxanes with different molecular weight were synthesized. The preparation included five steps which were hydroxyl protection, alkylation, anionic ring-opening polymerization, hydrosilylation and deprotection. The structure of reaction products was characterized by FT-IR, GC, 1H NMR. 2007 Qing Si Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Hydroxyl protection Alkylation Anionic ring-opening polymerization Hydrosilylation α-N,N-dihydroxy-ethylaminopropyl-ω- butylpolydimethylsiloxanes

Synthesis and characterization ofα-{ 3-[2-hydroxy-3-(N-methyl-N-hydroxy-ethylamino)propoxy]propyl}-ω-butylpolydimethylsiloxanes

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Chinese Chemical Letters 2008年第10期19卷 1196-1198页

作者： Hai Feng Sun Qing Si Zhang Meng Zhang yi tao yu Jian Ping Zong School of Chemical Engineering Shandong Institute of Light IndustryJinan 250100China School of Chemistry and Material Jiangnan UniversityWuxi 214122China

α-{3-[2-hydroxy-3-(N-methyl-N-hydroxyethylamino)propoxy]propyl}-α-butylpolydimethylsiloxanes III with various molecu-lar weights were prepared by epoxy addition ofα-[3-(2,3-epoxy-propoxy)propyl]-α-butylpolydimethylsiloxanesⅡand *** each step,the outcome compounds were characterized through FT-IR and NMR spectra,the results showed that each step was successfully carried out and objective products were achieved.

关键词： Anionic ring-opening polymerization Hydrosilylation Epoxy addition α-{3-[2-Hydroxy-3-(N-methyl-N-hydroxyethylamino)pro-poxy]propyl}-to-butylpolydimethylsiloxanes

Synthesis of polystyrene-styrene/butadiene diblock copolymers via reversible addition-fragmentation chain transfer miniemulsion polymerization

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Chinese Chemical Letters 2010年第12期21卷 1497-1500页

作者： Zhen Xi Wang Qing Hua Zhang yi tao yu Xiao Li Zhan Feng Qiu Chen Ji Hai Xiong Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China Institute of Energy Conversion Jiangxi Academy of Sciences Nanchang 330029 China

Polystyrene-styrene/butadiene diblock copolymers were synthesized via reversible addition-fragmentation chain transfer （RAFT） miniemulsion *** the polymerization process,the molecular weight distribution was narrow and the numerical molecular weight of the copolymers increased with increasing conversion of monomers,which was close to the ***-IR and ^1H NMR results indicated that the microstructure of the polymer was mainly 1,4-trans-butadiene with small amount of 1,2-units,and composition in the copolymers was obtained.

关键词： Reversible addition-fragmentation chain transfer Polystyrene-styrene/butadiene diblock copolymers Miniemulsion polymerization

Insight into the mechanisms and functions of spliceosomal snRNA pseudouridylation

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World Journal of Biological Chemistry 2014年第4期5卷 398-408页

作者： Hironori Adachi yi-tao yu Department of Biochemistry and Biophysics Center for RNA Biology University of Rochester Medical Center Rochester NY 14642 United States

Pseudouridines(Ψs) are the most abundant and highly conserved modified nucleotides found in various stable RNAs of all organisms. Most Ψs are clustered in regions that are functionally important for pre-m RNA splicing. Ψ has an extra hydrogen bond donor that endows RNA molecules with distinct properties that contribute significantly to RNA-mediated cellular processes. Experimental data indicate that spliceosomal sn RNA pseudouridylation can be catalyzed by both RNA-dependent and RNA-independent mechanisms. Recent work has also demonstrated that pseudouridylation can be induced at novel positions under stress conditions, suggesting a regulatory role for Ψ.

关键词： Pre-m RNA splicing U2 sn RNA Box H/ACA ribonucleoprotein Pseudouridine Induced RNA modification

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng tao Chen yu Han Jun Wang Shibo Xi yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Sporadic E responds to the 2022 Tonga volcano eruptions recorded by the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 20-28页

作者： Yangyi Sun tao yu Jin Wang Chi Long School of Geophysics and Geomatics China University of Geosciences(Wuhan)Wuhan 430047China School of Physics and Electronic Science Guizhou Normal UniversityGuizhou 550001China

In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe atmospheric disturbances caused by the Tonga volcanic eruptions on January 15,*** most prominent signature was the disappearance of the layer after~10:00 UT over Wuhan and Fuke,which was attributed to the vertical drift caused by the *** occurred intermittently after 13:00 UT following the arrival of the tropospheric Lamb *** examine the causal mechanism for the intermittence,we also included data of horizontal winds in the mesosphere and lower thermosphere region recorded by the meteor radars at Wuhan and Mohe in this *** wind disturbances with periods of~20 hours contributed to the formation of the layer in the nighttime on January 15.

关键词： sporadic E Tonga eruptions neutral wind disturbances

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang Li-Shuo Zheng yu-tao Zheng yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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InNi alloy-induced interface effect promoting the parallel electron transfer: improved photothermal catalytic CO2 hydrogenation

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Science China Chemistry 2025年

作者： Haoyu Zhang yuhang Li yu Nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye tao yu School of Chemical Engineering and Technology Tianjin University Eco-environment and Resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of Environmental Science and Engineering Tianjin University Advanced Catalytic Materials Research Center School of Materials Science and Engineering Tianjin University Research Center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

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