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The background of the total synthesis of yeast alanine transfer RNA

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Science China(Life Sciences) 2010年第1期53卷 19-21页

作者： QI GuoRong Institute of Biochemistry and Cell Biology,Shanghai Institute for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China Institute of Biochemistry and Cell Biology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Shanghai China

The research findings concerning the total synthesis of yeast alanine transfer RNA (yeast alanine trna) were successively published in Chinese Science Bulletin (1982) and Science

关键词： trna The background of the total synthesis of yeast alanine transfer RNA

Selenocysteine trnas as Central Components of Selenoprotein Biosynthesis in Eukaryotes

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Biomedical and Environmental Sciences 1997年第2期10卷 116-124页

作者： SANG ICK PARK JIN Mo PARK HAROLD S. CHITTUM EUN SUNG YANG BRADLEY A. CARLSON BYEONG JAE LEE AND DOLPH L. HATFIELD(Laboratory of Experimental Chrcinogenesis, National Cancer Insti tute, National Institutes of Health, Bethesda, MD 20892USA Laboratory o Laboratory of Experimental Carcinogenesis National Cancer Institute National Institutes of Health Bethesda MD 20892 USA.

Selenocysteine (Sec) trnas serve as carrier molecules for the biosynthesis of Sec from serine and to donate Sec to protein in response to specific UGA codons. In this study, we describe the current status of Sec trnas in higher animals and further we exarnine: (i) the Sec trna population in Drosophila; (ii) transcription of the Sec trna in vivo (in Xenopus oocytes) and in vitro (in Xenopus oocyte extracts); (iii) the effect of selenium on the Sec trna population in various rat tissues following replenishment of extremely selenium deficient rats with this element; and (iv) the biosynthesis of the modified bases on Sec trna in Xenopus oocytes

关键词： trna gene Selenocysteine trnas as Central Components of Selenoprotein Biosynthesis in Eukaryotes

Species-specific aminoacylation of Oryza sativa mitochondrial trna^(Trp)

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Chinese Science Bulletin 2006年第7期51卷 824-829页

作者： JIN Xiaoling TAO Zhijian JIA Jie HE Xinxia JIN Youxin College of Chemistry and Life Sciences Zhejiang Normal University Jinhua 321004 China State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China School of Enviroment Art Design Central South Forestry University Changsha 412004 China

Abstract The details of species- spe- cific aminoacylation in Oryza sativa mitochondrial trnaTrp by bacterial and eukaryotic (cytoplasm) tryptophanyl-trna synthetases (TrpRS) were inves- tigated. Seven single or multiple mutations of three bases (G73, U72, A 68) were made in O. sativa mi- tochondrial trnaTrp to the corresponding nucleotides present in human trnaTrp. In vitro transcripts of these mutant genes were tryptophanylated by Bacil- lus subtilis and human tryptophanyl-trna syntheta- ses (TrpRS), and the kinetic parameters were deter- mined. The results showed that the aminoacylation of seven mutant transcripts by B. subtilis TrpRS was 53.33%―99.79% less efficient than that by wild-type O. sativa mitochondrial trnaTrp, but was 4―330 times more efficient than that by human TrpRS. The mutant MPH7 (G73, U72 and C68 in O. sativa mito- chondrial trna were all replaced by the counterpart residues from human trnaTrp and showed a great change in aminoacylation efficiency. Our results in- dicate that the species-specific identity elements of O. sativa mitochondrial trnaTrp are similar to bacterial and eukaryotic (cytoplasm). They are mainly located at the discriminator base, the first and the fifth pairs of bases, the discriminator base G73, two bases in the acceptor stem G1/U72 and U5/A68. Our results also provide new data in support of the hypothesis that mitochondrial trnaTrp is of eubacterial origin.

关键词：水稻色氨酰 trna 合成酶 TrpRS 线粒体氨基酰化作用

Domain Structure of the Selenocysteine-specific Translation Factor SelB in Prokaryotes

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Biomedical and Environmental Sciences 1997年第2期10卷 125-128页

作者： AUGUST B■CK ROLF HILGENFELD PETER TORMAY REINHARD WILTING, AND MATTHIAS KROMAYER (Lehrstuhl fur Mikrobiologie der Universitat uüunchen, MiriaWard-Strasse 1a, D-80638 Munchen, Germany Institut fur olekulare Biotechnologie, Beutenbergtrasse 11,D-0770 Lehrstuhl für Mikrobiologie Universität München Germany.

Translation factor SelB is the key component for the specific decoding of UGA codons with selenocysteine at the ribosome. SelB binds selenocysteyl-trnaSec, guanine nucleotides and a secondary structure of the selenoprotein mRNA following the UGA at the 3' side. A comparison of the amino acid sequences of SelB species from E. coli,Desulfomicrobium baculatum, Clostridium thermoaceticum and Haemophilus influenzae showed that the proteins consist of at least four structural domains from which the Nterminal three are well conserved and share homology with elongation factor Tu whereas the C-terminal one is more variable and displays no similarity to any protein known. With the aid of the coordinates of EF-Tu the N-terminal part has been modelled into a 3D structure which exhibits intriguing features concerning its interaction with guanine nucleotides and other components of the translational apparatus. Cloning and expression of fragments of SelB and biochemical analysis of the purified truncated proteins showed that the C-terminal 19 kDa protein fragment is able to specifically bind to the selenoprotein mRNA. SelB, thus, is a translation factor functionally homologous to EF-Tu hooked up to the mRNA with its C-terminal end. The formation by SelB of a quaternary complex in vivo has been proven by overexpression of truncated genes of SelB and by demonstration that fragments comprising the mRNA or the trna binding domain inhibit selenocysteine insertion

关键词： mRNA EF Ts trna Domain Structure of the Selenocysteine-specific Translation Factor SelB in Prokaryotes Nature

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基于翻译调控的细菌耐药研究进展

微生物学通报 2022年第7期49卷 2767-2777页

作者：方慧颖张弓暨南大学生命与健康工程研究院功能蛋白质广东省普通高校重点实验室广东广州510632

由于抗生素的大量使用,细菌耐药问题凸显,直接威胁人类生命健康和世界经济发展。过去对于细菌耐药的遗传和分子机制研究较为透彻,而对应的调控机制研究相对较少。翻译调控作为生命体最重要的调控方式之一,在细菌耐药研究领域的重要性尚... 详细信息

由于抗生素的大量使用,细菌耐药问题凸显,直接威胁人类生命健康和世界经济发展。过去对于细菌耐药的遗传和分子机制研究较为透彻,而对应的调控机制研究相对较少。翻译调控作为生命体最重要的调控方式之一,在细菌耐药研究领域的重要性尚未被学术界充分重视。本文介绍了影响翻译过程的抗生素的主要作用机制,重点从核糖体的修饰和突变、trna总量的动态调控、trna氨酰化、trna甲基化、核糖体保护蛋白和翻译因子这几个方面概述了基于翻译调控的细菌耐药研究进展,为研究者们提供了一个基于翻译调控角度研究细菌耐药的新视角,同时也为开发靶向细菌翻译调控的新型抗生素提供一些新思路。

关键词：细菌耐药翻译调控核糖体 trna

蝽科线粒体基因组trna和rRNA基因的比较及应用(半翅目:蝽总科)

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福建农林大学学报（自然科学版） 2022年第6期51卷 782-791页

作者：廉丹魏久锋丁晓飞刘迎香赵清山西农业大学植物保护学院山西太谷030801

对蝽科4亚科线粒体基因组中22个trna和2个rRNA基因的序列特征、遗传距离和二级结构进行比较研究,采用贝叶斯法分别对这两个数据集构建了系统发育树.结果表明,蝽科26个物种的22个trna基因碱基组成中,多数种表现AT正偏斜,所有种表现GC正偏... 详细信息

对蝽科4亚科线粒体基因组中22个trna和2个rRNA基因的序列特征、遗传距离和二级结构进行比较研究,采用贝叶斯法分别对这两个数据集构建了系统发育树.结果表明,蝽科26个物种的22个trna基因碱基组成中,多数种表现AT正偏斜,所有种表现GC正偏斜;2个rRNA基因碱基组成中所有种均表现AT负偏斜和GC正偏斜.遗传距离结果表明:4亚科间舌蝽亚科和蝽亚科亲缘关系最近,益蝽亚科和短喙蝽亚科亲缘关系最远.蝽科昆虫trna比rRNA基因的二级结构保守.系统发育结果均表明短喙蝽亚科和益蝽亚科为单系群,蝽亚科和舌蝽亚科均未形成单系群.因此,trna和rRNA基因可用于蝽科昆虫的系统发育研究.

关键词：蝽科线粒体基因组 trna rRNA 比较研究系统发育

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Dnmt2的底物识别机制与生物学功能

生命科学 2022年第4期34卷 345-356页

作者：黄志宣王恩多中国科学院分子细胞科学卓越创新中心/上海生物化学与细胞生物学研究所分子生物学国家重点实验室上海200031 中国科学院大学北京100864 上海科技大学生命科学与技术学院上海201210

Dnmt2的同源基因首次在酵母基因组中被发现,由于其蛋白质序列与已知的DNA甲基转移酶家族成员DNMT1的序列高度同源,所以被认为是一个DNA甲基转移酶,归属于DNA甲基转.移酶家族。然而,一直没有足够的证据证明Dnmt2对DNA具有甲基转移能力。... 详细信息

Dnmt2的同源基因首次在酵母基因组中被发现,由于其蛋白质序列与已知的DNA甲基转移酶家族成员DNMT1的序列高度同源,所以被认为是一个DNA甲基转移酶,归属于DNA甲基转.移酶家族。然而,一直没有足够的证据证明Dnmt2对DNA具有甲基转移能力。直到2006年发现Dnmt2有催化trna^(Asp)(GUC)甲基化修饰的能力,才确定Dnmt2的功能是一种RNA甲基转移酶,负责催化trna上第38位胞嘧啶的甲基化修饰,但Dnmt2识别和催化底物trna的分子机制仍未被全面阐明。之前研究表明,Q34可以增强Dnmt2对trna^(Asp)(GUC)的催化活力;王恩多课题组发现人源Dnmt2对底物trna的关键识别位点是G34或I34,Dnmt2识别底物依赖于底物trna的反密码子环、D茎和可变环的关键位点和完整的三级结构。此外,Dnmt2在细胞代谢、胚胎发育、有丝分裂、表观遗传、肿瘤与免疫等方面发挥着重要作用。该文从进化保守性、底物识别机理、蛋白质结构与功能、修饰之间的调控等方面综述了Dnmt2在RNA修饰中的最新研究进展。

关键词：甲基转移酶 trna Dnmt2 5-甲基胞嘧啶分子机理

Innovation for ascertaining genomic islands in PAO1 and PA14 of Pseudomonas aeruginosa

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Chinese Science Bulletin 2009年第21期54卷 3991-3999页

作者： SONG Lei ZHANG XueHong Key Laboratory of Microbial Metabolism Ministry of Education School of Life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China College of Life and Environment Science Shanghai Normal University Shanghai 200234 China

Based on three distinct traits of genomic islands, a novel approach was developed to search for and determine genomic islands in special strains. Two genomic islands in Pseudomonas aeruginosa PAO1 and 7 genomic islands in Pseudomonas aeruginosa PA14 were defined with this method. Among the 9 genomic islands, 4 islands had been characterized before, while the other 5 islands were initially determined. The insert sites of 6 genomic islands are trna sequences, direct repeats of PA14GI-3 are relative to trnaLeu, and direct repeats of PA14GI-2 are at the 3′ end of bifunctional GMP synthase/ glutamine amidotransferase. Only direct repeats of PA14GI-4 are not clear. Among the 5 newly-found genomic islands, it was supposed that PA14GI-2 is a genomic island related to Hg2+ uptake, PA14GI-3 is a secretory activity genomic island, PA14GI-6 is a pathogenicity island, and functions of PA14GI-1 and PA14GI-5 are not clear. Finally, the tyrosine type integrases in PAO1GI-1, PA14GI-5 and PA14GI-7 were analyzed, and their binding and restriction sites were predicted.

关键词：基因组铜绿假单胞菌岛屿创新 PA 绿脓杆菌 trna 谷氨酰胺

同义密码子使用模式对多肽链共翻译折叠的影响研究进展

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微生物学通报 2023年第7期50卷 3146-3158页

作者：汪梦竹胡欣妍杨宣叶高明阳周建华西北民族大学生物医学研究中心生物工程与技术国家民委重点实验室甘肃兰州730030 西北民族大学生物医学研究中心甘肃省动物细胞技术创新中心甘肃兰州730030 西北民族大学生命科学与工程学院甘肃兰州730010 中国农业科学院兰州兽医研究所甘肃兰州730046

同义密码子使用模式作为核苷酸与氨基酸的纽带,其多样性介导了核糖体扫描速率,同时扩充了基因的遗传信息存储量。随着新型技术的应用,发现特异性密码子和密码子结合力可调节核糖体扫描速率并影响蛋白质构象。同义密码子使用模式通过多... 详细信息

同义密码子使用模式作为核苷酸与氨基酸的纽带,其多样性介导了核糖体扫描速率,同时扩充了基因的遗传信息存储量。随着新型技术的应用,发现特异性密码子和密码子结合力可调节核糖体扫描速率并影响蛋白质构象。同义密码子使用模式通过多种方式在不同环节影响着核糖体扫描速率,同时还影响着自身mRNA的稳定性。本文简述了密码子使用模式如何在核糖体扫描翻译mRNA的过程中实现对多肽链翻译延伸的调控,为今后生物工程学领域如何优化蛋白高效表达提供可参考的思路与理念。

关键词：同义密码子使用模式遗传信息基因表达核糖体扫描 trna