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Sakakibara H. Five unaddressed questions about cytokinin biosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2025; 76:1941-1949. [PMID: 39133104 PMCID: PMC12066119 DOI: 10.1093/jxb/erae348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Accepted: 08/10/2024] [Indexed: 08/13/2024]
Abstract
Cytokinins, a class of phytohormones, play crucial roles in regulating plant growth and stress responses through finely tuned feedback loops involving metabolic and signaling cascades. Over the past 25 years, studies have identified key genes involved in cytokinin biosynthesis and inactivation pathways. Nevertheless, several gaps remain in our understanding, particularly regarding the movement of intermediate metabolites between subcellular compartments and the discrepancy between the products of adenosine phosphate-isopentenyltransferase (IPT) and the substrate preferences of subsequent reactions. Recent gene discoveries related to lonely guy (LOG)-independent pathways suggest a spatial extension of cytokinin biosynthesis into the apoplast. Other intriguing issues remain to be addressed, such as elucidating the synthetic pathway for cis-zeatin and unraveling the molecular mechanisms governing selective substrate use by the cytokinin biosynthetic enzyme Tumor morphology root (Tmr) from the phytopathogen Agrobacterium tumefaciens. Further studies are needed to reveal a fully comprehensive picture of cytokinin metabolism.
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Affiliation(s)
- Hitoshi Sakakibara
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro, Tsurumi, Yokohama, Japan
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2
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Xu C, Wang X, Wu Y, Gao J, Zhang P, Zhao Y, Liu X, Wang P, Huang S. Molecular mechanisms underlying low temperature inhibition of grain filling in maize (Zea mays L.): coordination of growth and cold responses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:982-997. [PMID: 38743909 DOI: 10.1111/tpj.16811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/30/2024] [Accepted: 05/03/2024] [Indexed: 05/16/2024]
Abstract
Low temperature (LT) greatly restricts grain filling in maize (Zea mays L.), but the relevant molecular mechanisms are not fully understood. To better understand the effect of LT on grain development, 17 hybrids were subjected to LT stress in field trials over 3 years, and two hybrids of them with contrasting LT responses were exposed to 30/20°C and 20/10°C for 7 days during grain filling in a greenhouse. At LT, thousand-kernel weight declined, especially in LT-sensitive hybrid FM985, while grain-filling rate was on average about 48% higher in LT-tolerant hybrid DK159 than FM985. LT reduced starch synthesis in kernel mainly by suppression of transcript levels and enzyme activities for sucrose synthase and hexokinase. Brassinolide (BR) was abundant in DK159 kernel, and genes involved in BR and cytokinin signals were inducible by stress. LT downregulated the genes in light-harvesting complex and photosystem I/II subunits, accompanied by reduced photosynthetic rate and Fv/Fm in ear leaf. The LT-tolerant hybrid could maintain a high soluble sugar content and fast interconversion between sucrose and hexose in the stem internode and cob, improving assimilate allocation to kernel at LT stress and paving the way for simultaneous growth and LT stress responses.
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Affiliation(s)
- Chenchen Xu
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
- Beijing University of Agriculture, Beijing, 100096, China
| | - Xin Wang
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Yi Wu
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Jia Gao
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Ping Zhang
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Yating Zhao
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Xiaoli Liu
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Pu Wang
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Shoubing Huang
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
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3
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Argueso CT, Kieber JJ. Cytokinin: From autoclaved DNA to two-component signaling. THE PLANT CELL 2024; 36:1429-1450. [PMID: 38163638 PMCID: PMC11062471 DOI: 10.1093/plcell/koad327] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/25/2023] [Accepted: 11/03/2023] [Indexed: 01/03/2024]
Abstract
Since its first identification in the 1950s as a regulator of cell division, cytokinin has been linked to many physiological processes in plants, spanning growth and development and various responses to the environment. Studies from the last two and one-half decades have revealed the pathways underlying the biosynthesis and metabolism of cytokinin and have elucidated the mechanisms of its perception and signaling, which reflects an ancient signaling system evolved from two-component elements in bacteria. Mutants in the genes encoding elements involved in these processes have helped refine our understanding of cytokinin functions in plants. Further, recent advances have provided insight into the mechanisms of intracellular and long-distance cytokinin transport and the identification of several proteins that operate downstream of cytokinin signaling. Here, we review these processes through a historical lens, providing an overview of cytokinin metabolism, transport, signaling, and functions in higher plants.
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Affiliation(s)
- Cristiana T Argueso
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Joseph J Kieber
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
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Frébortová J, Frébort I. Biochemical and Structural Aspects of Cytokinin Biosynthesis and Degradation in Bacteria. Microorganisms 2021; 9:microorganisms9061314. [PMID: 34208724 PMCID: PMC8234997 DOI: 10.3390/microorganisms9061314] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 11/16/2022] Open
Abstract
It has been known for quite some time that cytokinins, hormones typical of plants, are also produced and metabolized in bacteria. Most bacteria can only form the tRNA-bound cytokinins, but there are examples of plant-associated bacteria, both pathogenic and beneficial, that actively synthesize cytokinins to interact with their host. Similar to plants, bacteria produce diverse cytokinin metabolites, employing corresponding metabolic pathways. The identification of genes encoding the enzymes involved in cytokinin biosynthesis and metabolism facilitated their detailed characterization based on both classical enzyme assays and structural approaches. This review summarizes the present knowledge on key enzymes involved in cytokinin biosynthesis, modifications, and degradation in bacteria, and discusses their catalytic properties in relation to the presence of specific amino acid residues and protein structure.
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Abstract
Covering: up to mid-2020 Terpenoids, also called isoprenoids, are the largest and most structurally diverse family of natural products. Found in all domains of life, there are over 80 000 known compounds. The majority of characterized terpenoids, which include some of the most well known, pharmaceutically relevant, and commercially valuable natural products, are produced by plants and fungi. Comparatively, terpenoids of bacterial origin are rare. This is counter-intuitive to the fact that recent microbial genomics revealed that almost all bacteria have the biosynthetic potential to create the C5 building blocks necessary for terpenoid biosynthesis. In this review, we catalogue terpenoids produced by bacteria. We collected 1062 natural products, consisting of both primary and secondary metabolites, and classified them into two major families and 55 distinct subfamilies. To highlight the structural and chemical space of bacterial terpenoids, we discuss their structures, biosynthesis, and biological activities. Although the bacterial terpenome is relatively small, it presents a fascinating dichotomy for future research. Similarities between bacterial and non-bacterial terpenoids and their biosynthetic pathways provides alternative model systems for detailed characterization while the abundance of novel skeletons, biosynthetic pathways, and bioactivies presents new opportunities for drug discovery, genome mining, and enzymology.
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Affiliation(s)
- Jeffrey D Rudolf
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | - Tyler A Alsup
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | - Baofu Xu
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | - Zining Li
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
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Carpentier P, Leprêtre C, Basset C, Douki T, Torelli S, Duarte V, Hamdane D, Fontecave M, Atta M. Structural, biochemical and functional analyses of tRNA-monooxygenase enzyme MiaE from Pseudomonas putida provide insights into tRNA/MiaE interaction. Nucleic Acids Res 2020; 48:9918-9930. [PMID: 32785618 PMCID: PMC7515727 DOI: 10.1093/nar/gkaa667] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 07/28/2020] [Accepted: 07/31/2020] [Indexed: 11/30/2022] Open
Abstract
MiaE (2-methylthio-N6-isopentenyl-adenosine37-tRNA monooxygenase) is a unique non-heme diiron enzyme that catalyzes the O2-dependent post-transcriptional allylic hydroxylation of a hypermodified nucleotide 2-methylthio-N6-isopentenyl-adenosine (ms2i6A37) at position 37 of selected tRNA molecules to produce 2-methylthio-N6-4-hydroxyisopentenyl-adenosine (ms2io6A37). Here, we report the in vivo activity, biochemical, spectroscopic characterization and X-ray crystal structure of MiaE from Pseudomonas putida. The investigation demonstrates that the putative pp-2188 gene encodes a MiaE enzyme. The structure shows that Pp-MiaE consists of a catalytic diiron(III) domain with a four alpha-helix bundle fold. A docking model of Pp-MiaE in complex with tRNA, combined with site directed mutagenesis and in vivo activity shed light on the importance of an additional linker region for substrate tRNA recognition. Finally, krypton-pressurized Pp-MiaE experiments, revealed the presence of defined O2 site along a conserved hydrophobic tunnel leading to the diiron active center.
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Affiliation(s)
- Philippe Carpentier
- Univ. Grenoble Alpes, CEA, CNRS, CBM-UMR 5249, 17 avenue des martyrs, Grenoble, France
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Chloé Leprêtre
- Univ. Grenoble Alpes, CEA, CNRS, CBM-UMR 5249, 17 avenue des martyrs, Grenoble, France
| | - Christian Basset
- Univ. Grenoble Alpes, CEA, CNRS, CBM-UMR 5249, 17 avenue des martyrs, Grenoble, France
| | - Thierry Douki
- Univ. Grenoble Alpes, CEA, CNRS, SyMMES, F-38000, 17 avenue des martyrs Grenoble, France
| | - Stéphane Torelli
- Univ. Grenoble Alpes, CEA, CNRS, CBM-UMR 5249, 17 avenue des martyrs, Grenoble, France
| | - Victor Duarte
- Univ. Grenoble Alpes, CEA, CNRS, CBM-UMR 5249, 17 avenue des martyrs, Grenoble, France
| | - Djemel Hamdane
- Laboratoire de Chimie des Processus Biologiques, UMR CNRS 8229, Collège de France-CNRS-Sorbonne Université, PSL Research University, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Marc Fontecave
- Laboratoire de Chimie des Processus Biologiques, UMR CNRS 8229, Collège de France-CNRS-Sorbonne Université, PSL Research University, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Mohamed Atta
- Univ. Grenoble Alpes, CEA, CNRS, CBM-UMR 5249, 17 avenue des martyrs, Grenoble, France
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Aoki MM, Emery RJN, Anjard C, Brunetti CR, Huber RJ. Cytokinins in Dictyostelia - A Unique Model for Studying the Functions of Signaling Agents From Species to Kingdoms. Front Cell Dev Biol 2020; 8:511. [PMID: 32714926 PMCID: PMC7316887 DOI: 10.3389/fcell.2020.00511] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 05/28/2020] [Indexed: 02/06/2023] Open
Abstract
Cytokinins (CKs) are a diverse group of evolutionarily significant growth-regulating molecules. While the CK biosynthesis and signal transduction pathways are the most well-understood in plant systems, these molecules have been identified in all kingdoms of life. This review follows the recent discovery of an expanded CK profile in the social amoeba, Dictyostelium discoideum. A comprehensive review on the present knowledge of CK biosynthesis, signal transduction, and CK-small molecule interactions within members of Dictyostelia will be summarized. In doing so, the utility of social amoebae will be highlighted as a model system for studying the evolution of these hormone-like signaling agents, which will set the stage for future research in this area.
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Affiliation(s)
- Megan M Aoki
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - R J Neil Emery
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - Christophe Anjard
- Institut Lumière Matière, CNRS UMR 5306, Université Claude Bernard Lyon 1, Université de Lyon, Lyon, France
| | - Craig R Brunetti
- Department of Biology, Trent University, Peterborough, ON, Canada
| | - Robert J Huber
- Department of Biology, Trent University, Peterborough, ON, Canada
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Algal neurotoxin biosynthesis repurposes the terpene cyclase structural fold into an N-prenyltransferase. Proc Natl Acad Sci U S A 2020; 117:12799-12805. [PMID: 32457155 DOI: 10.1073/pnas.2001325117] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Prenylation is a common biological reaction in all domains of life wherein prenyl diphosphate donors transfer prenyl groups onto small molecules as well as large proteins. The enzymes that catalyze these reactions are structurally distinct from ubiquitous terpene cyclases that, instead, assemble terpenes via intramolecular rearrangements of a single substrate. Herein, we report the structure and molecular details of a new family of prenyltransferases from marine algae that repurposes the terpene cyclase structural fold for the N-prenylation of glutamic acid during the biosynthesis of the potent neurochemicals domoic acid and kainic acid. We solved the X-ray crystal structure of the prenyltransferase found in domoic acid biosynthesis, DabA, and show distinct active site binding modifications that remodel the canonical magnesium (Mg2+)-binding motif found in terpene cyclases. We then applied our structural knowledge of DabA and a homologous enzyme from the kainic acid biosynthetic pathway, KabA, to reengineer their isoprene donor specificities (geranyl diphosphate [GPP] versus dimethylallyl diphosphate [DMAPP]) with a single amino acid change. While diatom DabA and seaweed KabA enzymes share a common evolutionary lineage, they are distinct from all other terpene cyclases, suggesting a very distant ancestor to the larger terpene synthase family.
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Hayashi Y, Ito T, Yoshimura T, Hemmi H. Utilization of an intermediate of the methylerythritol phosphate pathway, (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate, as the prenyl donor substrate for various prenyltransferases. Biosci Biotechnol Biochem 2017; 82:993-1002. [PMID: 29191109 DOI: 10.1080/09168451.2017.1398064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
(E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate (HMBPP) is an intermediate of the methylerythritol phosphate pathway. Utilization of HMBPP by lycopene elongase from Corynebacterium glutamicum, which is a UbiA-family prenyltransferase responsible for C50 carotenoid biosynthesis, was investigated using an Escherichia coli strain that contained the exogenous mevalonate pathway as well as the carotenoid biosynthetic pathway. Inhibition of the endogenous methylerythritol phosphate pathway resulted in loss of the production of C50 carotenoid flavuxanthin, while C40 lycopene formation was retained. Overexpression of E. coli ispH gene, which encodes HMBPP reductase, also decreased the production of flavuxanthin in E. coli cells. These results indicate the preference of lycopene elongase for HMBPP instead of the previously proposed substrate, dimethylallyl diphosphate. Furthermore, several (all-E)-prenyl diphosphate synthases, which are classified in a distinct family of prenyltransferase, were demonstrated to accept HMBPP, which implies that the compound is more widely used as a prenyl donor substrate than was previously expected.
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Affiliation(s)
- Yoshifumi Hayashi
- a Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences , Nagoya University , Nagoya , Japan
| | - Tomokazu Ito
- a Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences , Nagoya University , Nagoya , Japan
| | - Tohru Yoshimura
- a Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences , Nagoya University , Nagoya , Japan
| | - Hisashi Hemmi
- a Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences , Nagoya University , Nagoya , Japan
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10
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Feng Y, Zhang X, Wu T, Xu X, Han Z, Wang Y. Methylation effect on IPT5b gene expression determines cytokinin biosynthesis in apple rootstock. Biochem Biophys Res Commun 2017; 482:604-609. [DOI: 10.1016/j.bbrc.2016.11.080] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 11/14/2016] [Indexed: 10/20/2022]
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Huibin Z, Liu H, Aboulnaga E, Liu H, Cheng T, Xian M. Microbial Production of Isoprene: Opportunities and Challenges. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807833.ch16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Zou Huibin
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
- Qingdao University of Science and Technology; College of Chemical Engineering; No. 53 Zhengzhou Road Qingdao 266042 China
| | - Hui Liu
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
| | - Elhussiny Aboulnaga
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
- Mansoura University; Faculty of Agriculture; No. 60 Elgomhouria St. Mansoura 35516 Egypt
| | - Huizhou Liu
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
| | - Tao Cheng
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
| | - Mo Xian
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
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Frébortová J, Greplová M, Seidl MF, Heyl A, Frébort I. Biochemical Characterization of Putative Adenylate Dimethylallyltransferase and Cytokinin Dehydrogenase from Nostoc sp. PCC 7120. PLoS One 2015; 10:e0138468. [PMID: 26376297 PMCID: PMC4574047 DOI: 10.1371/journal.pone.0138468] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/31/2015] [Indexed: 12/20/2022] Open
Abstract
Cytokinins, a class of phytohormones, are adenine derivatives common to many different organisms. In plants, these play a crucial role as regulators of plant development and the reaction to abiotic and biotic stress. Key enzymes in the cytokinin synthesis and degradation in modern land plants are the isopentyl transferases and the cytokinin dehydrogenases, respectively. Their encoding genes have been probably introduced into the plant lineage during the primary endosymbiosis. To shed light on the evolution of these proteins, the genes homologous to plant adenylate isopentenyl transferase and cytokinin dehydrogenase were amplified from the genomic DNA of cyanobacterium Nostoc sp. PCC 7120 and expressed in Escherichia coli. The putative isopentenyl transferase was shown to be functional in a biochemical assay. In contrast, no enzymatic activity was detected for the putative cytokinin dehydrogenase, even though the principal domains necessary for its function are present. Several mutant variants, in which conserved amino acids in land plant cytokinin dehydrogenases had been restored, were inactive. A combination of experimental data with phylogenetic analysis indicates that adenylate-type isopentenyl transferases might have evolved several times independently. While the Nostoc genome contains a gene coding for protein with characteristics of cytokinin dehydrogenase, the organism is not able to break down cytokinins in the way shown for land plants.
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Affiliation(s)
- Jitka Frébortová
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Marta Greplová
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
| | - Michael F. Seidl
- Laboratory of Phytopathology, Wageningen University, Wageningen, The Netherlands
| | - Alexander Heyl
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Berlin, Germany
| | - Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, Czech Republic
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Creason AL, Vandeputte OM, Savory EA, Davis EW, Putnam ML, Hu E, Swader-Hines D, Mol A, Baucher M, Prinsen E, Zdanowska M, Givan SA, Jaziri ME, Loper JE, Mahmud T, Chang JH. Analysis of genome sequences from plant pathogenic Rhodococcus reveals genetic novelties in virulence loci. PLoS One 2014; 9:e101996. [PMID: 25010934 PMCID: PMC4092121 DOI: 10.1371/journal.pone.0101996] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 06/12/2014] [Indexed: 12/19/2022] Open
Abstract
Members of Gram-positive Actinobacteria cause economically important diseases to plants. Within the Rhodococcus genus, some members can cause growth deformities and persist as pathogens on a wide range of host plants. The current model predicts that phytopathogenic isolates require a cluster of three loci present on a linear plasmid, with the fas operon central to virulence. The Fas proteins synthesize, modify, and activate a mixture of growth regulating cytokinins, which cause a hormonal imbalance in plants, resulting in abnormal growth. We sequenced and compared the genomes of 20 isolates of Rhodococcus to gain insights into the mechanisms and evolution of virulence in these bacteria. Horizontal gene transfer was identified as critical but limited in the scale of virulence evolution, as few loci are conserved and exclusive to phytopathogenic isolates. Although the fas operon is present in most phytopathogenic isolates, it is absent from phytopathogenic isolate A21d2. Instead, this isolate has a horizontally acquired gene chimera that encodes a novel fusion protein with isopentyltransferase and phosphoribohydrolase domains, predicted to be capable of catalyzing and activating cytokinins, respectively. Cytokinin profiling of the archetypal D188 isolate revealed only one activate cytokinin type that was specifically synthesized in a fas-dependent manner. These results suggest that only the isopentenyladenine cytokinin type is synthesized and necessary for Rhodococcus phytopathogenicity, which is not consistent with the extant model stating that a mixture of cytokinins is necessary for Rhodococcus to cause leafy gall symptoms. In all, data indicate that only four horizontally acquired functions are sufficient to confer the trait of phytopathogenicity to members of the genetically diverse clade of Rhodococcus.
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Affiliation(s)
- Allison L. Creason
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon, United States of America
| | - Olivier M. Vandeputte
- Laboratoire de Biotechnologie Vegetale, Universite Libre de Bruxelles, Gosselies, Belgium
| | - Elizabeth A. Savory
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Edward W. Davis
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon, United States of America
| | - Melodie L. Putnam
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Erdong Hu
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - David Swader-Hines
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Adeline Mol
- Laboratoire de Biotechnologie Vegetale, Universite Libre de Bruxelles, Gosselies, Belgium
| | - Marie Baucher
- Laboratoire de Biotechnologie Vegetale, Universite Libre de Bruxelles, Gosselies, Belgium
| | - Els Prinsen
- University of Antwerp, Department of Biology, Laboratory of Plant Growth and Development, Antwerp, Belgium
| | - Magdalena Zdanowska
- University of Antwerp, Department of Biology, Laboratory of Plant Growth and Development, Antwerp, Belgium
| | - Scott A. Givan
- Informatics Research Core Facility, University of Missouri, Columbia, Missouri, United States of America
| | - Mondher El Jaziri
- Laboratoire de Biotechnologie Vegetale, Universite Libre de Bruxelles, Gosselies, Belgium
| | - Joyce E. Loper
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon, United States of America
- United States Department of Agriculture, Agricultural Research Service, Horticultural Crops Research Laboratory, Corvallis, Oregon, United States of America
| | - Taifo Mahmud
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon, United States of America
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, Oregon, United States of America
| | - Jeff H. Chang
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
- Molecular and Cellular Biology Program, Oregon State University, Corvallis, Oregon, United States of America
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, United States of America
- * E-mail:
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Kudo T, Makita N, Kojima M, Tokunaga H, Sakakibara H. Cytokinin activity of cis-zeatin and phenotypic alterations induced by overexpression of putative cis-Zeatin-O-glucosyltransferase in rice. PLANT PHYSIOLOGY 2012; 160:319-31. [PMID: 22811434 PMCID: PMC3440209 DOI: 10.1104/pp.112.196733] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
cis-Zeatin (cZ) is generally regarded as a cytokinin with little or no activity, compared with the highly active trans-zeatin (tZ). Although recent studies suggested possible roles for cZ, its physiological significance remains unclear. In our studies with rice (Oryza sativa), cZ inhibited seminal root elongation and up-regulated cytokinin-inducible genes, and its activities were comparable to those of tZ. Tracer experiments showed that exogenously supplied cZ-riboside was mainly converted into cZ derivatives but scarcely into tZ derivatives, indicating that isomerizations of cZ derivatives into tZ derivatives are a minor pathway in rice cytokinin metabolism. We identified three putative cZ-O-glucosyltransferases (cZOGT1, cZOGT2, and cZOGT3) in rice. The cZOGTs preferentially catalyzed O-glucosylation of cZ and cZ-riboside rather than tZ and tZ-riboside in vitro. Transgenic rice lines ectopically overexpressing the cZOGT1 and cZOGT2 genes exhibited short-shoot phenotypes, delay of leaf senescence, and decrease in crown root number, while cZOGT3 overexpressor lines did not show shortened shoots. These results propose that cZ activity has a physiological impact on the growth and development of rice.
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Ueda N, Kojima M, Suzuki K, Sakakibara H. Agrobacterium tumefaciens tumor morphology root plastid localization and preferential usage of hydroxylated prenyl donor is important for efficient gall formation. PLANT PHYSIOLOGY 2012; 159:1064-72. [PMID: 22589470 PMCID: PMC3387694 DOI: 10.1104/pp.112.198572] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Upon Agrobacterium tumefaciens infection of a host plant, Tumor morphology root (Tmr) a bacterial adenosine phosphate-isopentenyltransferase (IPT), creates a metabolic bypass in the plastid for direct synthesis of trans-zeatin (tZ) with 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate as the prenyl donor. To understand the biological importance of Tmr function for gall formation, we compared Tmr and Trans-zeatin secretion (Tzs) another agrobacterial IPT that functions within the bacterial cell. Although there is no significant difference in their substrate specificities in vitro, ectopic overexpression of Tzs in Arabidopsis (Arabidopsis thaliana) resulted in the accumulation of comparable amounts of tZ- and N⁶-(Δ²-isopentenyl)adenine (iP)-type cytokinins, whereas overexpression of Tmr resulted exclusively in the accumulation of tZ-type cytokinins. Ectopic expression of Tzs in plant cells yields only small amounts of the polypeptide in plastid-enriched fractions. Obligatory localization of Tzs into Arabidopsis plastid stroma by translational fusions with ferredoxin transit peptide (TP-Tzs) increased the accumulation of both tZ- and iP-type cytokinins. Replacement of tmr on the Ti plasmid with tzs, TP-tzs, or an Arabidopsis plastidic IPT induced the formation of smaller galls than wild-type A. tumefaciens, and they were accompanied by the accumulation of iP-type cytokinins. Tmr is thus specialized for plastid localization and preferential usage of 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate in vivo and is important for efficient gall formation.
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Qiu W, Liu M, Qiao G, Jiang J, Xie L, Zhuo R. An Isopentyl Transferase Gene Driven by the Stress-Inducible rd29A Promoter Improves Salinity Stress Tolerance in Transgenic Tobacco. PLANT MOLECULAR BIOLOGY REPORTER 2012; 30:519-528. [DOI: 10.1007/s11105-011-0337-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/17/2025]
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17
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Sp Chal LX. Cytokinins - recent news and views of evolutionally old molecules. FUNCTIONAL PLANT BIOLOGY : FPB 2012; 39:267-284. [PMID: 32480780 DOI: 10.1071/fp11276] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 03/06/2012] [Indexed: 05/03/2023]
Abstract
Cytokinins (CKs) are evolutionally old and highly conserved low-mass molecules that have been identified in almost all known organisms. In plants, they evolved into an important group of plant hormones controlling many physiological and developmental processes throughout the whole lifespan of the plant. CKs and their functions are, however, not unique to plants. In this review, the strategies and mechanisms of plants - and phylogenetically distinct plant-interacting organisms such as bacteria, fungi, nematodes and insects employing CKs or regulation of CK status in plants - are described and put into their evolutionary context. The major breakthroughs made in the last decade in the fields of CK biosynthesis, degradation and signalling are also summarised.
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Affiliation(s)
- Luk X Sp Chal
- Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 11, CZ-78371 Olomouc, Czech Republic. Email
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Tokunaga H, Kojima M, Kuroha T, Ishida T, Sugimoto K, Kiba T, Sakakibara H. Arabidopsis lonely guy (LOG) multiple mutants reveal a central role of the LOG-dependent pathway in cytokinin activation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 69:355-65. [PMID: 22059596 DOI: 10.1111/j.1365-313x.2011.04795.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Cytokinins are phytohormones that play key roles in the maintenance of stem cell activity in plants. Although alternative single-step and two-step activation pathways for cytokinin have been proposed, the significance of the single-step pathway which is catalyzed by LONELY GUY (LOG), is not fully understood. We analyzed the metabolic flow of cytokinin activation in Arabidopsis log multiple mutants using stable isotope-labeled tracers and characterized the mutants' morphological and developmental phenotypes. In tracer experiments, cytokinin activation was inhibited most pronouncedly by log7, while the other log mutations had cumulative effects. Although sextuple or lower-order mutants did not show drastic phenotypes in vegetative growth, the log1log2log3log4log5log7log8 septuple T-DNA insertion mutant in which the LOG-dependent pathway is impaired, displayed severe retardation of shoot and root growth with defects in the maintenance of the apical meristems. Detailed observation of the mutants showed that LOG7 was required for the maintenance of shoot apical meristem size. LOG7 was also suggested to play a role for normal primary root growth together with LOG3 and LOG4. These results suggest a dominant role of the single-step activation pathway mediated by LOGs for cytokinin production, and overlapping but differentiated functions of the members of the LOG gene family in growth and development.
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Affiliation(s)
- Hiroki Tokunaga
- RIKEN Plant Science Center, 1-7-22, Suehiro, Tsurumi, Yokohama 230-0045, Japan
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Zalabák D, Pospíšilová H, Šmehilová M, Mrízová K, Frébort I, Galuszka P. Genetic engineering of cytokinin metabolism: prospective way to improve agricultural traits of crop plants. Biotechnol Adv 2011; 31:97-117. [PMID: 22198203 DOI: 10.1016/j.biotechadv.2011.12.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 12/02/2011] [Indexed: 01/02/2023]
Abstract
Cytokinins (CKs) are ubiquitous phytohormones that participate in development, morphogenesis and many physiological processes throughout plant kingdom. In higher plants, mutants and transgenic cells and tissues with altered activity of CK metabolic enzymes or perception machinery, have highlighted their crucial involvement in different agriculturally important traits, such as productivity, increased tolerance to various stresses and overall plant morphology. Furthermore, recent precise metabolomic analyses have elucidated the specific occurrence and distinct functions of different CK types in various plant species. Thus, smooth manipulation of active CK levels in a spatial and temporal way could be a very potent tool for plant biotechnology in the future. This review summarises recent advances in cytokinin research ranging from transgenic alteration of CK biosynthetic, degradation and glucosylation activities and CK perception to detailed elucidation of molecular processes, in which CKs work as a trigger in model plants. The first attempts to improve the quality of crop plants, focused on cereals are discussed, together with proposed mechanism of action of the responses involved.
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Affiliation(s)
- David Zalabák
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Šlechtitelů 11, 783 71 Olomouc, Czech Republic.
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Frébort I, Kowalska M, Hluska T, Frébortová J, Galuszka P. Evolution of cytokinin biosynthesis and degradation. JOURNAL OF EXPERIMENTAL BOTANY 2011; 62:2431-52. [PMID: 21321050 DOI: 10.1093/jxb/err004] [Citation(s) in RCA: 227] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cytokinin hormones are important regulators of development and environmental responses of plants that execute their action via the molecular machinery of signal perception and transduction. The limiting step of the whole process is the availability of the hormone in suitable concentrations in the right place and at the right time to interact with the specific receptor. Hence, the hormone concentrations in individual tissues, cells, and organelles must be properly maintained by biosynthetic and metabolic enzymes. Although there are merely two active cytokinins, isopentenyladenine and its hydroxylated derivative zeatin, a variety of conjugates they may form and the number of enzymes/isozymes with varying substrate specificity involved in their biosynthesis and conversion gives the plant a variety of tools for fine tuning of the hormone level. Recent genome-wide studies revealed the existence of the respective coding genes and gene families in plants and in some bacteria. This review summarizes present knowledge on the enzymes that synthesize cytokinins, form cytokinin conjugates, and carry out irreversible elimination of the hormones, including their phylogenetic analysis and possible variations in different organisms.
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Affiliation(s)
- Ivo Frébort
- Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 813/21, CZ-78371 Olomouc, Czech Republic.
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21
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Hwang HH, Wang MH, Lee YL, Tsai YL, Li YH, Yang FJ, Liao YC, Lin SK, Lai EM. Agrobacterium-produced and exogenous cytokinin-modulated Agrobacterium-mediated plant transformation. MOLECULAR PLANT PATHOLOGY 2010; 11:677-90. [PMID: 20696005 PMCID: PMC6640272 DOI: 10.1111/j.1364-3703.2010.00637.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Agrobacterium tumefaciens is a plant pathogenic bacterium that causes neoplastic growths, called 'crown gall', via the transfer and integration of transferred DNA (T-DNA) from the bacterium into the plant genome. We characterized an acetosyringone (AS)-induced tumour-inducing (Ti) plasmid gene, tzs (trans-zeatin synthesizing), that is responsible for the synthesis of the plant hormone cytokinin in nopaline-type A. tumefaciens strains. The loss of Tzs protein expression and trans-zeatin secretions by the tzs frameshift (tzs-fs) mutant is associated with reduced tumorigenesis efficiency on white radish stems and reduced transformation efficiencies on Arabidopsis roots. Complementation of the tzs-fs mutant with a wild-type tzs gene restored wild-type levels of trans-zeatin secretions and transformation efficiencies. Exogenous application of cytokinin during infection increased the transient transformation efficiency of Arabidopsis roots infected by strains lacking Tzs, which suggests that the lower transformation efficiency resulted from the lack of Agrobacterium-produced cytokinin. Interestingly, although the tzs-fs mutant displayed reduced tumorigenesis efficiency on several tested plants, the loss of Tzs enhanced tumorigenesis efficiencies on green pepper and cowpea. These data strongly suggest that Tzs, by synthesizing trans-zeatin at early stage(s) of the infection process, modulates plant transformation efficiency by A. tumefaciens.
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Affiliation(s)
- Hau-Hsuan Hwang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan.
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22
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Chu HM, Chen FY, Ko TP, Wang AHJ. Binding and catalysis of Humulus lupulus adenylate isopentenyltransferase for the synthesis of isopentenylated diadenosine polyphosphates. FEBS Lett 2010; 584:4083-8. [PMID: 20807533 DOI: 10.1016/j.febslet.2010.08.038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 08/26/2010] [Accepted: 08/26/2010] [Indexed: 10/19/2022]
Abstract
Various plant developmental processes involve phytohormones such as cytokinins. Isopentenyltransferase (IPT) reaction is the key rate-limiting step in cytokinin biosynthesis that transfers the isopentenyl (iP) group from dimethylallyl diphosphate to the N6-amino group of adenine. Here, a series of diadenosine polyphosphates (Ap(n)A) were screened as possible substrates of IPT, among which diadenosine tetraphosphate, diadenosine pentaphosphate and diadenosine hexaphosphate showed higher affinity than did the authentic substrates ADP and ATP. In addition, formation of mono-isopentenyl Ap(n)A and di-isopentenyl Ap(n)A was observed. Judging by the existing biosynthetic and hydrolytic systems for Ap(n)A in plants, Ap(n)A and isopentenyl-Ap(n)A may occur in the plant cells, with functional importance.
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Affiliation(s)
- Hsing-Mao Chu
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
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Chu HM, Ko TP, Wang AHJ. Crystal structure and substrate specificity of plant adenylate isopentenyltransferase from Humulus lupulus: distinctive binding affinity for purine and pyrimidine nucleotides. Nucleic Acids Res 2009; 38:1738-48. [PMID: 20007608 PMCID: PMC2836551 DOI: 10.1093/nar/gkp1093] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Cytokinins are important plant hormones, and their biosynthesis most begins with the transfer of isopentenyl group from dimethylallyl diphosphate (DMAPP) to the N6-amino group of adenine by either adenylate isopentenyltransferase (AIPT) or tRNA–IPT. Plant AIPTs use ATP/ADP as an isopentenyl acceptor and bacterial AIPTs prefer AMP, whereas tRNA–IPTs act on specific sites of tRNA. Here, we present the crystal structure of an AIPT–ATP complex from Humulus lupulus (HlAIPT), which is similar to the previous structures of Agrobacterium AIPT and yeast tRNA–IPT. The enzyme is structurally homologous to the NTP-binding kinase family of proteins but forms a solvent-accessible channel that binds to the donor substrate DMAPP, which is directed toward the acceptor substrate ATP/ADP. When measured with isothermal titration calorimetry, some nucleotides displayed different binding affinities to HlAIPT with an order of ATP > dATP ∼ ADP > GTP > CTP > UTP. Two basic residues Lys275 and Lys220 in HlAIPT interact with the β and γ-phosphate of ATP. By contrast, the interactions are absent in Agrobacterium AIPT because they are replaced by the acidic residues Asp221 and Asp171. Despite its structural similarity to the yeast tRNA–IPT, HlAIPT has evolved with a different binding strategy for adenylate.
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Affiliation(s)
- Hsing-Mao Chu
- Institute of Biochemical Sciences, National Taiwan University, Taipei, 106, Taiwan
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Werner T, Schmülling T. Cytokinin action in plant development. CURRENT OPINION IN PLANT BIOLOGY 2009; 12:527-38. [PMID: 19740698 DOI: 10.1016/j.pbi.2009.07.002] [Citation(s) in RCA: 405] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Accepted: 07/13/2009] [Indexed: 05/20/2023]
Abstract
Cytokinin regulates many important aspects of plant development in aerial and subterranean organs. The hormone is part of an intrinsic genetic network controlling organ development and growth in these two distinct environments that plants have to cope with. Cytokinin also mediates the responses to variable extrinsic factors, such as light conditions in the shoot and availability of nutrients and water in the root, and has a role in the response to biotic and abiotic stress. Together, these activities contribute to the fine-tuning of quantitative growth regulation in plants. We review recent progress in understanding the cytokinin system and its links to the regulatory pathways that respond to internal and external signals.
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Affiliation(s)
- Tomás Werner
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences (DCPS), Freie Universität Berlin, Albrecht-Thaer-Weg 6, D-14195 Berlin, Germany.
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Chimnaronk S, Forouhar F, Sakai J, Yao M, Tron CM, Atta M, Fontecave M, Hunt JF, Tanaka I. Snapshots of dynamics in synthesizing N(6)-isopentenyladenosine at the tRNA anticodon. Biochemistry 2009; 48:5057-65. [PMID: 19435325 PMCID: PMC2786004 DOI: 10.1021/bi900337d] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bacterial and eukaryotic tRNAs that decode codons starting with uridine have a hydrophobically hypermodified adenosine at position 37 (A(37)) adjacent to the 3'-end of the anticodon, which is essential for efficient and highly accurate protein translation by the ribosome. However, it remains unclear as to how the corresponding tRNAs are selected to be modified by alkylation at the correct position of the adenosine base. We have determined a series of crystal structures of bacterial tRNA isopentenyltransferase (MiaA) in apo- and tRNA-bound forms, which completely render snapshots of substrate selections during the modification of RNA. A compact evolutionary inserted domain (herein swinging domain) in MiaA that exhibits as a highly mobile entity moves around the catalytic domain as likely to reach and trap the tRNA substrate. Thereby, MiaA clamps the anticodon stem loop of the tRNA substrate between the catalytic and swinging domains, where the two conserved elongated residues from the swinging domain pinch the two flanking A(36) and A(38) together to squeeze out A(37) into the reaction tunnel. The site-specific isopentenylation of RNA is thus ensured by a characteristic pinch-and-flip mechanism and by a reaction tunnel to confine the substrate selection. Furthermore, combining information from soaking experiments with structural comparisons, we propose a mechanism for the ordered substrate binding of MiaA.
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Affiliation(s)
- Sarin Chimnaronk
- Faculty of Advanced Life Sciences, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan
- Institute of Molecular Biology and Genetics, Mahidol University, Salaya Campus, Nakornpathom 73170, Thailand
| | - Farhad Forouhar
- Department of Biological Sciences, Northeast Structural Genomics Consortium, Columbia University, New York, NY 10027, USA
| | - Junichi Sakai
- Faculty of Advanced Life Sciences, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan
| | - Min Yao
- Faculty of Advanced Life Sciences, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan
| | - Cecile M. Tron
- IRTSV,CEA/CNRS/UJF, LCBM, UMR5249, 38054 Grenoble, France
| | - Mohamed Atta
- IRTSV,CEA/CNRS/UJF, LCBM, UMR5249, 38054 Grenoble, France
| | - Marc Fontecave
- IRTSV,CEA/CNRS/UJF, LCBM, UMR5249, 38054 Grenoble, France
| | - John F. Hunt
- Department of Biological Sciences, Northeast Structural Genomics Consortium, Columbia University, New York, NY 10027, USA
| | - Isao Tanaka
- Faculty of Advanced Life Sciences, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan
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