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González-García MP, Sáez A, Lanza M, Hoyos P, Bustillo-Avendaño E, Pacios LF, Gradillas A, Moreno-Risueno MA, Hernaiz MJ, del Pozo JC. Synthetically derived BiAux modulates auxin co-receptor activity to stimulate lateral root formation. PLANT PHYSIOLOGY 2024; 195:1694-1711. [PMID: 38378170 PMCID: PMC11142373 DOI: 10.1093/plphys/kiae090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 01/12/2024] [Accepted: 01/13/2024] [Indexed: 02/22/2024]
Abstract
The root system plays an essential role in plant growth and adaptation to the surrounding environment. The root clock periodically specifies lateral root prebranch sites (PBS), where a group of pericycle founder cells (FC) is primed to become lateral root founder cells and eventually give rise to lateral root primordia or lateral roots (LRs). This clock-driven organ formation process is tightly controlled by modulation of auxin content and signaling. Auxin perception entails the physical interaction of TRANSPORT INHIBITOR RESPONSE 1 (TIR1) or AUXIN SIGNALING F-BOX (AFBs) proteins with AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) repressors to form a co-receptor system. Despite the apparent simplicity, the understanding of how specific auxin co-receptors are assembled remains unclear. We identified the compound bis-methyl auxin conjugated with N-glucoside, or BiAux, in Arabidopsis (Arabidopsis thaliana) that specifically induces the formation of PBS and the emergence of LR, with a slight effect on root elongation. Docking analyses indicated that BiAux binds to F-box proteins, and we showed that BiAux function depends on TIR1 and AFB2 F-box proteins and AUXIN RESPONSE FACTOR 7 activity, which is involved in FC specification and LR formation. Finally, using a yeast (Saccharomyces cerevisiae) heterologous expression system, we showed that BiAux favors the assemblage of specific co-receptors subunits involved in LR formation and enhances AUXIN/INDOLE-3-ACETIC ACID 28 protein degradation. These results indicate that BiAux acts as an allosteric modulator of specific auxin co-receptors. Therefore, BiAux exerts a fine-tune regulation of auxin signaling aimed to the specific formation of LR among the many development processes regulated by auxin.
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Affiliation(s)
- Mary Paz González-García
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), 28040 Madrid, Spain
| | - Angela Sáez
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Universidad Francisco de Vitoria, Facultad de Ciencias Experimentales, Edificio E., 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Mónica Lanza
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Pilar Hoyos
- Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain
| | - Estefano Bustillo-Avendaño
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Luis F Pacios
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Ana Gradillas
- Centro de Metabolómica y Bioanálisis (CEMBIO), Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, 28660 Boadilla del Monte, Madrid, Spain
| | - Miguel A Moreno-Risueno
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), 28040 Madrid, Spain
| | - María José Hernaiz
- Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain
| | - Juan C del Pozo
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA/CSIC), Universidad Politécnica de Madrid (UPM)—Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-CSIC (INIA/CSIC), Campus Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain
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Prusinska J, Uzunova V, Schmitzer P, Weimer M, Bell J, Napier RM. The differential binding and biological efficacy of auxin herbicides. PEST MANAGEMENT SCIENCE 2023; 79:1305-1315. [PMID: 36458868 PMCID: PMC10952535 DOI: 10.1002/ps.7294] [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: 09/26/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Auxin herbicides have been used for selective weed control for 75 years and they continue to be amongst the most widely used weed control agents globally. The auxin herbicides fall into five chemical classes, with two herbicides not classified, and in all cases it is anticipated that recognition in the plant starts with binding to the Transport Inhibitor Response 1 (TIR1) family of auxin receptors. There is evidence that some classes of auxins act selectively with certain clades of receptors, although a comprehensive structure-activity relationship has not been available. RESULTS Using purified receptor proteins to measure binding efficacy we have conducted quantitative structure activity relationship (qSAR) assays using representative members of the three receptor clades in Arabidopsis, TIR1, AFB2 and AFB5. Complementary qSAR data for biological efficacy at the whole-plant level using root growth inhibition and foliar phytotoxicity assays have also been analyzed for each family of auxin herbicides, including for the afb5-1 receptor mutant line. CONCLUSIONS Comparisons of all these assays highlight differences in receptor selectivity and some systematic differences between results for binding in vitro and activity in vivo. The results could provide insights into weed spectrum differences between the different classes of auxin herbicides, as well as the potential resistance and cross-resistance implications for this herbicide class. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
| | | | - Paul Schmitzer
- Corteva AgriscienceCrop Protection Discovery & DevelopmentIndianapolisIndianaUSA
| | - Monte Weimer
- Corteva AgriscienceCrop Protection Discovery & DevelopmentIndianapolisIndianaUSA
| | - Jared Bell
- Corteva AgriscienceCrop Protection Discovery & DevelopmentIndianapolisIndianaUSA
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Zhang Y, Yu J, Xu X, Wang R, Liu Y, Huang S, Wei H, Wei Z. Molecular Mechanisms of Diverse Auxin Responses during Plant Growth and Development. Int J Mol Sci 2022; 23:ijms232012495. [PMID: 36293351 PMCID: PMC9604407 DOI: 10.3390/ijms232012495] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/13/2022] [Accepted: 10/15/2022] [Indexed: 11/16/2022] Open
Abstract
The plant hormone auxin acts as a signaling molecule to regulate numerous developmental processes throughout all stages of plant growth. Understanding how auxin regulates various physiological and developmental processes has been a hot topic and an intriguing field. Recent studies have unveiled more molecular details into how diverse auxin responses function in every aspect of plant growth and development. In this review, we systematically summarized and classified the molecular mechanisms of diverse auxin responses, and comprehensively elaborated the characteristics and multilevel regulation mechanisms of the canonical transcriptional auxin response. On this basis, we described the characteristics and differences between different auxin responses. We also presented some auxin response genes that have been genetically modified in plant species and how their changes impact various traits of interest. Finally, we summarized some important aspects and unsolved questions of auxin responses that need to be focused on or addressed in future research. This review will help to gain an overall understanding of and some insights into the diverse molecular mechanisms of auxin responses in plant growth and development that are instrumental in harnessing genetic resources in molecular breeding of extant plant species.
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Affiliation(s)
- Yang Zhang
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education, Heilongjiang University, Harbin 150500, China
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China
| | - Jiajie Yu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China
| | - Xiuyue Xu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China
| | - Ruiqi Wang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China
| | - Yingying Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China
| | - Shan Huang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin 150040, China
| | - Hairong Wei
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
| | - Zhigang Wei
- Engineering Research Center of Agricultural Microbiology Technology, Ministry of Education, Heilongjiang University, Harbin 150500, China
- Heilongjiang Provincial Key Laboratory of Plant Genetic Engineering and Biological Fermentation Engineering for Cold Region, School of Life Sciences, Heilongjiang University, Harbin 150080, China
- Correspondence: or
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Abstract
Auxin signaling regulates growth and developmental processes in plants. The core of nuclear auxin signaling relies on just three components: TIR1/AFBs, Aux/IAAs, and ARFs. Each component is itself made up of several domains, all of which contribute to the regulation of auxin signaling. Studies of the structural aspects of these three core signaling components have deepened our understanding of auxin signaling dynamics and regulation. In addition to the structured domains of these components, intrinsically disordered regions within the proteins also impact auxin signaling outcomes. New research is beginning to uncover the role intrinsic disorder plays in auxin-regulated degradation and subcellular localization. Structured and intrinsically disordered domains affect auxin perception, protein degradation dynamics, and DNA binding. Taken together, subtle differences within the domains and motifs of each class of auxin signaling component affect signaling outcomes and specificity.
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Affiliation(s)
- Nicholas Morffy
- Department of Biology, Duke University, Durham, North Carolina 27708, USA
- Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, Missouri 63130, USA
| | - Lucia C Strader
- Department of Biology, Duke University, Durham, North Carolina 27708, USA
- Center for Science and Engineering Living Systems (CSELS), Washington University, St. Louis, Missouri 63130, USA
- Center for Engineering Mechanobiology, Washington University, St. Louis, Missouri 63130, USA
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Dai Y, Zhang S, Sun X, Li G, Yuan L, Li F, Zhang H, Zhang S, Chen G, Wang C, Sun R. Comparative Transcriptome Analysis of Gene Expression and Regulatory Characteristics Associated with Different Vernalization Periods in Brassica rapa. Genes (Basel) 2020; 11:E392. [PMID: 32260536 PMCID: PMC7231026 DOI: 10.3390/genes11040392] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/17/2020] [Accepted: 04/03/2020] [Indexed: 12/17/2022] Open
Abstract
Brassica rapa is an important Chinese vegetable crop that is beneficial to human health. The primary factor affecting B. rapa yield is low temperature, which promotes bolting and flowering, thereby lowering its commercial value. However, quickened bolting and flowering can be used for rapid breeding. Therefore, studying the underlying molecular mechanism of vernalization in B.rapa is crucial for solving production-related problems. Here, the transcriptome of two B. rapa accessions were comprehensively analyzed during different vernalization periods. During vernalization, a total of 974,584,022 clean reads and 291.28 Gb of clean data were obtained. Compared to the reference genome of B. rapa, 44,799 known genes and 2280 new genes were identified. A self-organizing feature map analysis of 21,035 differentially expressed genes was screened in two B. rapa accessions, 'Jin Wawa' and 'Xiao Baojian'. The analysis indicated that transcripts related to the plant hormone signal transduction, starch and sucrose metabolism, photoperiod and circadian clock, and vernalization pathways changed notably at different vernalization periods. Moreover, different expression patterns of TPS, UGP, CDF, VIN1, and seven hormone pathway genes were observed during vernalization between the two accessions. The transcriptome results of this study provide a new perspective on the changes that occur during B. rapavernalization, as well as serve as an excellent reference for B. rapa breeding.
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Affiliation(s)
- Yun Dai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Shujiang Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Xiao Sun
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Guoliang Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Lingyun Yuan
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Fei Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Hui Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Shifan Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Guohu Chen
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Chenggang Wang
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Rifei Sun
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
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Abstract
The root meristem-one of the plant's centers of continuous growth-is a conveyer belt in which cells of different identities are pushed through gradients along the root's longitudinal axis. An auxin gradient has long been implicated in controlling the progression of cell states in the root meristem. Recent work has shown that a PLETHORA (PLT) protein transcription factor gradient, which is under a delayed auxin response, has a dose-dependent effect on the differentiation state of cells. The direct effect of auxin concentration on differential transcriptional outputs remains unclear. Genomic and other analyses of regulatory sequences show that auxin responses are likely controlled by combinatorial inputs from transcription factors outside the core auxin signaling pathway. The passage through the meristem exposes cells to varying positional signals that could help them interpret auxin inputs independent of gradient effects. One open question is whether cells process information from the changes in the gradient over time as they move through the auxin gradient.
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Affiliation(s)
- Bruno Guillotin
- New York University, The Department of Biology, The Center for Genomics and Systems Biology, New York, NY, United States
| | - Kenneth D Birnbaum
- New York University, The Department of Biology, The Center for Genomics and Systems Biology, New York, NY, United States.
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Upadhyay AK, Arora S, Pandey DK, Chaudhary B. Interspersed 5'cis-regulatory elements ascertain the spatio-temporal transcription of cytoskeletal profilin gene family in Arabidopsis. Comput Biol Chem 2019; 80:177-186. [PMID: 30974345 DOI: 10.1016/j.compbiolchem.2019.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 03/23/2019] [Accepted: 03/31/2019] [Indexed: 10/27/2022]
Abstract
Spatio-temporal expression patterns of cytoskeleton-associated profilin (PRF) family proteins in response to varied environmental stimuli are tightly regulated. Functional analyses of PRFs have revealed their crucial roles in varied developmental and stress related traits, but very little is implicit pertaining to cis-acting regulatory elements that regulate such intricate expression patterns. Here, we identified cis-elements with their varying distribution frequencies by scanning 1.5kbp upstream sequences of 5'regulatory regions of PRFs of dicot and monocot plant species. Predicted cis-elements in the regulatory sub-regions of Arabidopsis PRFs (AtPRFs) were predominantly associated with development-responsive motifs (DREs), light responsive elements (LREs), hormonal responsive elements (HREs), core motifs and stress-responsive elements (SREs). Interestingly, DREs, LREs and core promoter motifs, were extensively distributed up to the distal end of 5'regulatory regions on contrary to HREs present closer to the translational start site in Arabidopsis. The evolutionary footprints of predicted orthologous cis-elements were conserved, and preferably located in the proximal regions of 5'regulatory regions of evolutionarily diverged plant species. We also explored comprehensive tissue-specific global gene expression levels of PRFs under diverse hormonal and abiotic stress regimes. In response, the PRFs exhibited large transcriptional biases in a time- and organ-dependent manner. Further, the methodical elucidation of spatial expression analysis of predicted cis-elements binding transcription factors and relevant PRFs showed notable correlation. Results indicate that binding transcription factors' expression data is largely informative for envisaging their precise roles in the spatial regulation of target PRFs. These results highlight the importance of PRFs during plant development; and establish a relationship between their spatial expression patterns and presence of respective regulatory motifs in their promoter sequences. This information could be employed in future studies and field-utilization of cell wall structural genes.
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Affiliation(s)
- Arnav K Upadhyay
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201310, India
| | - Sakshi Arora
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201310, India
| | - Dhananjay K Pandey
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201310, India
| | - Bhupendra Chaudhary
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201310, India.
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Matthes MS, Best NB, Robil JM, Malcomber S, Gallavotti A, McSteen P. Auxin EvoDevo: Conservation and Diversification of Genes Regulating Auxin Biosynthesis, Transport, and Signaling. MOLECULAR PLANT 2019; 12:298-320. [PMID: 30590136 DOI: 10.1016/j.molp.2018.12.012] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 12/02/2018] [Accepted: 12/16/2018] [Indexed: 05/08/2023]
Abstract
The phytohormone auxin has been shown to be of pivotal importance in growth and development of land plants. The underlying molecular players involved in auxin biosynthesis, transport, and signaling are quite well understood in Arabidopsis. However, functional characterizations of auxin-related genes in economically important crops, specifically maize and rice, are still limited. In this article, we comprehensively review recent functional studies on auxin-related genes in both maize and rice, compared with what is known in Arabidopsis, and highlight conservation and diversification of their functions. Our analysis is illustrated by phylogenetic analysis and publicly available gene expression data for each gene family, which will aid in the identification of auxin-related genes for future research. Current challenges and future directions for auxin research in maize and rice are discussed. Developments in gene editing techniques provide powerful tools for overcoming the issue of redundancy in these gene families and will undoubtedly advance auxin research in crops.
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Affiliation(s)
- Michaela Sylvia Matthes
- Division of Biological Sciences, Interdisciplinary Plant Group and Missouri Maize Center, University of Missouri-Columbia, 301 Christopher Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Norman Bradley Best
- Division of Biological Sciences, Interdisciplinary Plant Group and Missouri Maize Center, University of Missouri-Columbia, 301 Christopher Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Janlo M Robil
- Division of Biological Sciences, Interdisciplinary Plant Group and Missouri Maize Center, University of Missouri-Columbia, 301 Christopher Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Simon Malcomber
- Department of Biological Sciences, California State University, Long Beach, CA 90840, USA
| | - Andrea Gallavotti
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ 08854-8020, USA; Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA
| | - Paula McSteen
- Division of Biological Sciences, Interdisciplinary Plant Group and Missouri Maize Center, University of Missouri-Columbia, 301 Christopher Bond Life Sciences Center, Columbia, MO 65211, USA.
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Jue D, Sang X, Liu L, Shu B, Wang Y, Liu C, Wang Y, Xie J, Shi S. Comprehensive analysis of the longan transcriptome reveals distinct regulatory programs during the floral transition. BMC Genomics 2019; 20:126. [PMID: 30744552 PMCID: PMC6371577 DOI: 10.1186/s12864-019-5461-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 01/17/2019] [Indexed: 12/18/2022] Open
Abstract
Background Longan (Dimocarpus longan Lour.) is an important fruit tree in the subtropical regions of Southeast Asia and Australia. Among the factors affecting D. longan fruit yield, the difficulty and instability of blossoming is one of the most challenging issues. Perpetual flowering (PF) is a crucial trait for fruit trees and is directly linked to production potential. Therefore, studying the molecular regulatory mechanism of longan PF traits is crucial for understanding and solving problems related to flowering. In this study, comparative transcriptome analysis was performed using two longan cultivars that display opposite flowering phenotypes during floral induction. Results We obtained 853.72 M clean reads comprising 125.08 Gb. After comparing these data with the longan genome, 27,266 known genes and 1913 new genes were detected. Significant differences in gene expression were observed between the two genotypes, with 6150 and 6202 differentially expressed genes (DEGs) for ‘SJ’ and ‘SX’, respectively. The transcriptional landscape of floral transition at the early stage was very different in these two longan genotypes with respect to key hormones, circadian rhythm, sugar metabolism, and transcription factors. Almost all flowering-related DEGs identified are involved in photoperiod and circadian clock pathways, such as CONSTANS-like (COL), two-component response regulator-like (APRRs), gigantea (GI), and early flowering (EFL). In addition, the leafy (LFY) gene, which is the central floral meristem identity gene, may inhibit PF formation in ‘SJ’. Conclusion This study provides a platform for understanding the molecular mechanisms responsible for changes between PF and seasonal flowering (SF) longan genotypes and may benefit studies on PF trait mechanisms of evergreen fruit trees. Electronic supplementary material The online version of this article (10.1186/s12864-019-5461-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dengwei Jue
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China.,School of Advanced Agriculture and Bioengineering, Yangtze Normal University, Chongqing, 408100, China
| | - Xuelian Sang
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China
| | - Liqin Liu
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China
| | - Bo Shu
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China
| | - Yicheng Wang
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China
| | - Chengming Liu
- College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Yi Wang
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China
| | - Jianghui Xie
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China.
| | - Shengyou Shi
- Key Laboratory of Tropical Fruit Biology (Ministry of Agriculture), South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, 524091, China. .,School of Advanced Agriculture and Bioengineering, Yangtze Normal University, Chongqing, 408100, China.
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Quareshy M, Prusinska J, Kieffer M, Fukui K, Pardal AJ, Lehmann S, Schafer P, del Genio CI, Kepinski S, Hayashi K, Marsh A, Napier RM. The Tetrazole Analogue of the Auxin Indole-3-acetic Acid Binds Preferentially to TIR1 and Not AFB5. ACS Chem Biol 2018; 13:2585-2594. [PMID: 30138566 DOI: 10.1021/acschembio.8b00527] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Indole-3-acetic acid (auxin) is considered one of the cardinal hormones in plant growth and development. It regulates a wide range of processes throughout the plant. Synthetic auxins exploit the auxin-signaling pathway and are valuable as herbicidal agrochemicals. Currently, despite a diversity of chemical scaffolds all synthetic auxins have a carboxylic acid as the active core group. By applying bio-isosteric replacement we discovered that indole-3-tetrazole was active by surface plasmon resonance spectrometry, showing that the tetrazole could initiate assembly of the Transport Inhibitor Resistant 1 (TIR1) auxin coreceptor complex. We then tested the tetrazole's efficacy in a range of whole plant physiological assays and in protoplast reporter assays, which all confirmed auxin activity, albeit rather weak. We then tested indole-3-tetrazole against the AFB5 homologue of TIR1, finding that binding was selective against TIR1, absent with AFB5. The kinetics of binding to TIR1 are contrasted to those for the herbicide picloram, which shows the opposite receptor preference, as it binds to AFB5 with far greater affinity than to TIR1. The basis of the preference of indole-3-tetrazole for TIR1 was revealed to be a single residue substitution using molecular docking, and assays using tir1 and afb5 mutant lines confirmed selectivity in vivo. Given the potential that a TIR1-selective auxin might have for unmasking receptor-specific actions, we followed a rational design, lead optimization campaign, and a set of chlorinated indole-3-tetrazoles was synthesized. Improved affinity for TIR1 and the preference for binding to TIR1 was maintained for 4- and 6-chloroindole-3-tetrazoles, coupled with improved efficacy in vivo. This work expands the range of auxin chemistry for the design of receptor-selective synthetic auxins.
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Affiliation(s)
| | | | - Martin Kieffer
- Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, U.K
| | - Kosuke Fukui
- Department of Biochemistry, Okayama University of Science, 1-1 Ridaicho, Kita-ku, Okayama-shi Okayama 700-0005, Japan
| | | | - Silke Lehmann
- Warwick Integrative Synthetic Biology Centre, Coventry CV4 7AL, U.K
| | - Patrick Schafer
- Warwick Integrative Synthetic Biology Centre, Coventry CV4 7AL, U.K
| | | | - Stefan Kepinski
- Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, U.K
| | - Kenichiro Hayashi
- Department of Biochemistry, Okayama University of Science, 1-1 Ridaicho, Kita-ku, Okayama-shi Okayama 700-0005, Japan
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11
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Tao S, Estelle M. Mutational studies of the Aux/IAA proteins in Physcomitrella reveal novel insights into their function. THE NEW PHYTOLOGIST 2018; 218:1534-1542. [PMID: 29461641 PMCID: PMC6054139 DOI: 10.1111/nph.15039] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 01/09/2018] [Indexed: 05/27/2023]
Abstract
The plant hormone auxin regulates many aspects of plant growth and development. Auxin signaling involves hormone perception by the TRANSPORT INHIBITOR RESPONSE/AUXIN F-BOX (TIR1/AFB)-Aux/IAA co-receptor system, and the subsequent degradation of the Aux/IAA transcriptional repressors by the ubiquitin proteasome pathway. This leads to the activation of downstream gene expression and diverse physiological responses. Here, we investigate how the structural elements in the Aux/IAAs determine their function in Auxin perception and transcriptional repression. We took advantage of the facile genetics of the moss Physcomitrella patens to determine the activity of wild-type and mutant PpIAA1a proteins in a Δaux/iaa null background. In this way, Aux/IAA function was characterized at the molecular and physiological levels without the interference of genetic redundancy. We identified and characterized degron variants in Aux/IAAs that affect their stability and Auxin response. We also demonstrated that neither the Aux/IAA EAR motif nor Aux/IAA oligomerization is essential for the repressive function of Aux/IAA. Our study demonstrates how key elements within the Aux/IAA proteins fine tune stability and repressor activity, as well as the long-term developmental outcome.
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Affiliation(s)
- Sibo Tao
- Section of Cell and Developmental Biology and Howard Hughes Medical Institute, University of California San Diego, La Jolla, CA 92093, USA
| | - Mark Estelle
- Section of Cell and Developmental Biology and Howard Hughes Medical Institute, University of California San Diego, La Jolla, CA 92093, USA
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12
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Kircher S, Schopfer P. The plant hormone auxin beats the time for oscillating, light-regulated lateral root induction. Development 2018; 145:dev.169839. [DOI: 10.1242/dev.169839] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 10/29/2018] [Indexed: 11/20/2022]
Abstract
The molecular mechanism underlying the periodic induction of lateral roots, a paradigmatic example of clock-driven organ formation in plant development, is presently a matter of ongoing, controversial debate. Here we provide experimental evidence that this clock is frequency-modulated by light and that auxin serves as a mediator for translating continuous light signals into discontinuous gene activation signals preceding the initiation of lateral roots in Arabidopsis seedlings. Based on this evidence, we propose a molecular model of an ultradian biological clock involving auxin-dependent degradation of an AUX/IAA-type transcription repressor as a flexible, frequency-controlling delay element. This model widens the bandwidth of biological clocks by adding a new type that allows the pace of organ formation to adapt to the changing environmental demands of the growing plant.
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Affiliation(s)
- Stefan Kircher
- Department of Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University, Schänzlestr. 1, D-79104-Freiburg, Germany
| | - Peter Schopfer
- Department of Molecular Plant Physiology, Faculty of Biology, Albert-Ludwigs-University, Schänzlestr. 1, D-79104-Freiburg, Germany
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13
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Cano A, Sánchez-García AB, Albacete A, González-Bayón R, Justamante MS, Ibáñez S, Acosta M, Pérez-Pérez JM. Enhanced Conjugation of Auxin by GH3 Enzymes Leads to Poor Adventitious Rooting in Carnation Stem Cuttings. FRONTIERS IN PLANT SCIENCE 2018; 9:566. [PMID: 29755501 PMCID: PMC5932754 DOI: 10.3389/fpls.2018.00566] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/10/2018] [Indexed: 05/05/2023]
Abstract
Commercial carnation (Dianthus caryophyllus) cultivars are vegetatively propagated from axillary stem cuttings through adventitious rooting; a process which is affected by complex interactions between nutrient and hormone levels and is strongly genotype-dependent. To deepen our understanding of the regulatory events controlling this process, we performed a comparative study of adventitious root (AR) formation in two carnation cultivars with contrasting rooting performance, "2101-02 MFR" and "2003 R 8", as well as in the reference cultivar "Master". We provided molecular evidence that localized auxin response in the stem cutting base was required for efficient adventitious rooting in this species, which was dynamically established by polar auxin transport from the leaves. In turn, the bad-rooting behavior of the "2003 R 8" cultivar was correlated with enhanced synthesis of indole-3-acetic acid conjugated to aspartic acid by GH3 proteins in the stem cutting base. Treatment of stem cuttings with a competitive inhibitor of GH3 enzyme activity significantly improved rooting of "2003 R 8". Our results allowed us to propose a working model where endogenous auxin homeostasis regulated by GH3 proteins accounts for the cultivar dependency of AR formation in carnation stem cuttings.
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Affiliation(s)
- Antonio Cano
- Departamento de Biología Vegetal (Fisiología Vegetal), Universidad de Murcia, Murcia, Spain
| | | | - Alfonso Albacete
- Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-Consejo Superior de Investigaciones Científicas, Murcia, Spain
| | | | | | - Sergio Ibáñez
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche, Spain
| | - Manuel Acosta
- Departamento de Biología Vegetal (Fisiología Vegetal), Universidad de Murcia, Murcia, Spain
| | - José Manuel Pérez-Pérez
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche, Spain
- *Correspondence: José Manuel Pérez-Pérez, arolab.edu.umh.es;
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14
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Goralogia GS, Liu T, Zhao L, Panipinto PM, Groover ED, Bains YS, Imaizumi T. CYCLING DOF FACTOR 1 represses transcription through the TOPLESS co-repressor to control photoperiodic flowering in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:244-262. [PMID: 28752516 PMCID: PMC5634919 DOI: 10.1111/tpj.13649] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/15/2017] [Accepted: 07/21/2017] [Indexed: 05/18/2023]
Abstract
CYCLING DOF FACTOR 1 (CDF1) and its homologs play an important role in the floral transition by repressing the expression of floral activator genes such as CONSTANS (CO) and FLOWERING LOCUS T (FT) in Arabidopsis. The day-length-specific removal of CDF1-dependent repression is a critical mechanism in photoperiodic flowering. However, the mechanism by which CDF1 represses CO and FT transcription remained elusive. Here we demonstrate that Arabidopsis CDF proteins contain non-EAR motif-like conserved domains required for interaction with the TOPLESS (TPL) co-repressor protein. This TPL interaction confers a repressive function on CDF1, as mutations of the N-terminal TPL binding domain largely impair the ability of CDF1 protein to repress its targets. TPL proteins are present on specific regions of the CO and FT promoters where CDF1 binds during the morning. In addition, TPL binding increases when CDF1 expression is elevated, suggesting that TPL is recruited to these promoters in a time-dependent fashion by CDFs. Moreover, reduction of TPL activity induced by expressing a dominant negative version of TPL (tpl-1) in phloem companion cells results in early flowering and a decreased sensitivity to photoperiod in a manner similar to a cdf loss-of-function mutant. Our results indicate that the mechanism of CDF1 repression is through the formation of a CDF-TPL transcriptional complex, which reduces the expression levels of CO and FT during the morning for seasonal flowering.
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Affiliation(s)
- Greg S. Goralogia
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
| | - Tongkun Liu
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
- Department of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Lin Zhao
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
- Key Laboratory of Soybean Biology of Chinese Education Ministry, Northeast Agricultural University, Harbin 150030, China
| | - Paul M. Panipinto
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
| | - Evan D. Groover
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
| | - Yashkarn S. Bains
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
| | - Takato Imaizumi
- Department of Biology, University of Washington, Seattle, WA, 98195-1800, USA
- For correspondence:
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15
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Zemlyanskaya EV, Wiebe DS, Omelyanchuk NA, Levitsky VG, Mironova VV. Meta-analysis of transcriptome data identified TGTCNN motif variants associated with the response to plant hormone auxin in Arabidopsis thaliana L. J Bioinform Comput Biol 2017; 14:1641009. [PMID: 27122321 DOI: 10.1142/s0219720016410092] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Auxin is the major regulator of plant growth and development. It regulates gene expression via a family of transcription factors (ARFs) that bind to auxin responsive elements (AuxREs) in the gene promoters. The canonical AuxREs found in regulatory regions of many auxin responsive genes contain the TGTCTC core motif, whereas ARF binding site is a degenerate TGTCNN with TGTCGG strongly preferred. Thereby two questions arise: which TGTCNN variants are functional AuxRE cores and whether different TGTCNN variants have distinct functional roles? In this study, we performed meta-analysis of microarray data to reveal TGTCNN variants essential for auxin response and to characterize their functional features. Our results indicate that four TGTCNN motifs (TGTCTC, TGTCCC, TGTCGG, and TGTCTG) are associated with auxin up-regulation and two (TGTCGG, TGTCAT) with auxin down-regulation, but to a lesser extent. The genes having some of these motifs in their regulatory regions showed time-specific auxin response. Functional annotation of auxin up- and down-regulated genes also revealed GO terms specific for the auxin-regulated genes with certain TGTCNN variants in their promoters. Our results provide an idea that various TGTCNN motifs may play distinct roles in the auxin regulation of gene expression.
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Affiliation(s)
- Elena V Zemlyanskaya
- * Department for Systems Biology, Institute of Cytology and Genetics SB RAS, 10 Lavrentyev Ave., Novosibirsk 630090, Russia.,† Laboratory of Computational Transcriptomics and Evolutionary Bioinformatics, Novosibirsk State University, 2 Pirogov Str., Novosibirsk 630090, Russia
| | - Daniil S Wiebe
- * Department for Systems Biology, Institute of Cytology and Genetics SB RAS, 10 Lavrentyev Ave., Novosibirsk 630090, Russia.,† Laboratory of Computational Transcriptomics and Evolutionary Bioinformatics, Novosibirsk State University, 2 Pirogov Str., Novosibirsk 630090, Russia
| | - Nadezhda A Omelyanchuk
- * Department for Systems Biology, Institute of Cytology and Genetics SB RAS, 10 Lavrentyev Ave., Novosibirsk 630090, Russia.,† Laboratory of Computational Transcriptomics and Evolutionary Bioinformatics, Novosibirsk State University, 2 Pirogov Str., Novosibirsk 630090, Russia
| | - Victor G Levitsky
- * Department for Systems Biology, Institute of Cytology and Genetics SB RAS, 10 Lavrentyev Ave., Novosibirsk 630090, Russia.,† Laboratory of Computational Transcriptomics and Evolutionary Bioinformatics, Novosibirsk State University, 2 Pirogov Str., Novosibirsk 630090, Russia
| | - Victoria V Mironova
- * Department for Systems Biology, Institute of Cytology and Genetics SB RAS, 10 Lavrentyev Ave., Novosibirsk 630090, Russia.,† Laboratory of Computational Transcriptomics and Evolutionary Bioinformatics, Novosibirsk State University, 2 Pirogov Str., Novosibirsk 630090, Russia
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16
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Denay G, Chahtane H, Tichtinsky G, Parcy F. A flower is born: an update on Arabidopsis floral meristem formation. CURRENT OPINION IN PLANT BIOLOGY 2017; 35:15-22. [PMID: 27721031 DOI: 10.1016/j.pbi.2016.09.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 09/20/2016] [Accepted: 09/22/2016] [Indexed: 05/23/2023]
Abstract
In Arabidopsis, floral meristems appear on the flanks of the inflorescence meristem. Their stereotypic development, ultimately producing the four whorls of floral organs, is essentially controlled by a network coordinating growth and cell-fate determination. This network integrates hormonal signals, transcriptional regulators, and mechanical constraints. Mechanisms regulating floral meristem formation have been studied at many different scales, from protein structure to tissue modeling. In this paper, we review recent findings related to the emergence of the floral meristem and floral fate determination and examine how this field has been impacted by recent technological developments.
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Affiliation(s)
- Grégoire Denay
- Laboratory of Plant & Cell Physiology, CNRS, CEA, Univ. Grenoble Alpes, INRA, 38000 Grenoble, France
| | - Hicham Chahtane
- Department of Plant Biology and Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
| | - Gabrielle Tichtinsky
- Laboratory of Plant & Cell Physiology, CNRS, CEA, Univ. Grenoble Alpes, INRA, 38000 Grenoble, France
| | - François Parcy
- Laboratory of Plant & Cell Physiology, CNRS, CEA, Univ. Grenoble Alpes, INRA, 38000 Grenoble, France.
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17
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Metabolomics and Cheminformatics Analysis of Antifungal Function of Plant Metabolites. Metabolites 2016; 6:metabo6040031. [PMID: 27706030 PMCID: PMC5192437 DOI: 10.3390/metabo6040031] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 09/26/2016] [Accepted: 09/27/2016] [Indexed: 12/24/2022] Open
Abstract
Fusarium head blight (FHB), primarily caused by Fusarium graminearum, is a devastating disease of wheat. Partial resistance to FHB of several wheat cultivars includes specific metabolic responses to inoculation. Previously published studies have determined major metabolic changes induced by pathogens in resistant and susceptible plants. Functionality of the majority of these metabolites in resistance remains unknown. In this work we have made a compilation of all metabolites determined as selectively accumulated following FHB inoculation in resistant plants. Characteristics, as well as possible functions and targets of these metabolites, are investigated using cheminformatics approaches with focus on the likelihood of these metabolites acting as drug-like molecules against fungal pathogens. Results of computational analyses of binding properties of several representative metabolites to homology models of fungal proteins are presented. Theoretical analysis highlights the possibility for strong inhibitory activity of several metabolites against some major proteins in Fusarium graminearum, such as carbonic anhydrases and cytochrome P450s. Activity of several of these compounds has been experimentally confirmed in fungal growth inhibition assays. Analysis of anti-fungal properties of plant metabolites can lead to the development of more resistant wheat varieties while showing novel application of cheminformatics approaches in the analysis of plant/pathogen interactions.
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18
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Simm S, Scharf KD, Jegadeesan S, Chiusano ML, Firon N, Schleiff E. Survey of Genes Involved in Biosynthesis, Transport, and Signaling of Phytohormones with Focus on Solanum lycopersicum. Bioinform Biol Insights 2016; 10:185-207. [PMID: 27695302 PMCID: PMC5038615 DOI: 10.4137/bbi.s38425] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/15/2016] [Accepted: 08/16/2016] [Indexed: 12/19/2022] Open
Abstract
Phytohormones control the development and growth of plants, as well as their response to biotic and abiotic stress. The seven most well-studied phytohormone classes defined today are as follows: auxins, ethylene, cytokinin, abscisic acid, jasmonic acid, gibberellins, and brassinosteroids. The basic principle of hormone regulation is conserved in all plants, but recent results suggest adaptations of synthesis, transport, or signaling pathways to the architecture and growth environment of different plant species. Thus, we aimed to define the extent to which information from the model plant Arabidopsis thaliana is transferable to other plants such as Solanum lycopersicum. We extracted the co-orthologues of genes coding for major pathway enzymes in A. thaliana from the translated genomes of 12 species from the clade Viridiplantae. Based on predicted domain architecture and localization of the identified proteins from all 13 species, we inspected the conservation of phytohormone pathways. The comparison was complemented by expression analysis of (co-) orthologous genes in S. lycopersicum. Altogether, this information allowed the assignment of putative functional equivalents between A. thaliana and S. lycopersicum but also pointed to some variations between the pathways in eudicots, monocots, mosses, and green algae. These results provide first insights into the conservation of the various phytohormone pathways between the model system A. thaliana and crop plants such as tomato. We conclude that orthologue prediction in combination with analysis of functional domain architecture and intracellular localization and expression studies are sufficient tools to transfer information from model plants to other plant species. Our results support the notion that hormone synthesis, transport, and response for most part of the pathways are conserved, and species-specific variations can be found.
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Affiliation(s)
- Stefan Simm
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany.; Cluster of Excellence Macromolecular Complexes, Institute for Molecular Cell Biology of Plants, Frankfurt am Main, Germany
| | - Klaus-Dieter Scharf
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany.; Cluster of Excellence Macromolecular Complexes, Institute for Molecular Cell Biology of Plants, Frankfurt am Main, Germany
| | - Sridharan Jegadeesan
- Department of Vegetable Research, Institute for Plant Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan, Israel.; The Robert H. Smith Faculty of Agriculture, Food and Environment, The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Maria Luisa Chiusano
- Department of Soil, Plants Environmental and Animal Production Sciences, Laboratory of Computer Aided Biosciences, University of Studies of Naples Federico II, Portici, Naples, Italy
| | - Nurit Firon
- Department of Vegetable Research, Institute for Plant Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan, Israel
| | - Enrico Schleiff
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany.; Cluster of Excellence Macromolecular Complexes, Institute for Molecular Cell Biology of Plants, Frankfurt am Main, Germany
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19
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Functional analysis of molecular interactions in synthetic auxin response circuits. Proc Natl Acad Sci U S A 2016; 113:11354-11359. [PMID: 27647902 DOI: 10.1073/pnas.1604379113] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Auxin-regulated transcription pivots on the interaction between the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) repressor proteins and the AUXIN RESPONSE FACTOR (ARF) transcription factors. Recent structural analyses of ARFs and Aux/IAAs have raised questions about the functional complexes driving auxin transcriptional responses. To parse the nature and significance of ARF-DNA and ARF-Aux/IAA interactions, we analyzed structure-guided variants of synthetic auxin response circuits in the budding yeast Saccharomyces cerevisiae Our analysis revealed that promoter architecture could specify ARF activity and that ARF19 required dimerization at two distinct domains for full transcriptional activation. In addition, monomeric Aux/IAAs were able to repress ARF activity in both yeast and plants. This systematic, quantitative structure-function analysis identified a minimal complex-comprising a single Aux/IAA repressing a pair of dimerized ARFs-sufficient for auxin-induced transcription.
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20
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Abstract
The plant hormone auxin (indole-3-acetic acid, IAA) controls growth and developmental responses throughout the life of a plant. A combination of molecular, genetic and biochemical approaches has identified several key components involved in auxin signal transduction. Rapid auxin responses in the nucleus include transcriptional activation of auxin-regulated genes and degradation of transcriptional repressor proteins. The nuclear auxin receptor is an integral component of the protein degradation machinery. Although auxin signalling in the nucleus appears to be short and simple, recent studies indicate that there is a high degree of diversity and complexity, largely due to the existence of multigene families for each of the major molecular components. Current studies are attempting to identify interacting partners among these families, and to define the molecular mechanisms involved in the interactions. Future goals are to determine the levels of regulation of the key components of the transcriptional complex, to identify higher-order complexes and to integrate this pathway with other auxin signal transduction pathways, such as the pathway that is activated by auxin binding to a different receptor at the outer surface of the plasma membrane. In this case, auxin binding triggers a signal cascade that affects a number of rapid cytoplasmic responses. Details of this pathway are currently under investigation.
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21
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Ben-Gera H, Dafna A, Alvarez JP, Bar M, Mauerer M, Ori N. Auxin-mediated lamina growth in tomato leaves is restricted by two parallel mechanisms. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 86:443-57. [PMID: 27121172 DOI: 10.1111/tpj.13188] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 04/05/2016] [Accepted: 04/06/2016] [Indexed: 05/04/2023]
Abstract
In the development of tomato compound leaves, local auxin maxima points, separated by the expression of the Aux/IAA protein SlIAA9/ENTIRE (E), direct the formation of discrete leaflets along the leaf margin. The local auxin maxima promote leaflet initiation, while E acts between leaflets to inhibit auxin response and lamina growth, enabling leaflet separation. Here, we show that a group of auxin response factors (ARFs), which are targeted by miR160, antagonizes auxin response and lamina growth in conjunction with E. In wild-type leaf primordia, the miR160-targeted ARFs SlARF10A and SlARF17 are expressed in leaflets, and SlmiR160 is expressed in provascular tissues. Leaf overexpression of the miR160-targeted ARFs SlARF10A, SlARF10B or SlARF17, led to reduced lamina and increased leaf complexity, and suppressed auxin response in young leaves. In agreement, leaf overexpression of miR160 resulted in simplified leaves due to ectopic lamina growth between leaflets, reminiscent of e leaves. Genetic interactions suggest that E and miR160-targeted ARFs act partially redundantly but are both required for local inhibition of lamina growth between initiating leaflets. These results show that different types of auxin signal antagonists act cooperatively to ensure leaflet separation in tomato leaf margins.
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Affiliation(s)
- Hadas Ben-Gera
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and The Otto Warburg Minerva Center for Agricultural Biotechnology, Hebrew University, P.O. Box 12, Rehovot, 76100, Israel
| | - Asaf Dafna
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and The Otto Warburg Minerva Center for Agricultural Biotechnology, Hebrew University, P.O. Box 12, Rehovot, 76100, Israel
| | - John Paul Alvarez
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
- School of Biological Sciences, Monash University, Clayton Campus, Melbourne, Vic., 3800, Australia
| | - Maya Bar
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and The Otto Warburg Minerva Center for Agricultural Biotechnology, Hebrew University, P.O. Box 12, Rehovot, 76100, Israel
| | - Mareike Mauerer
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and The Otto Warburg Minerva Center for Agricultural Biotechnology, Hebrew University, P.O. Box 12, Rehovot, 76100, Israel
| | - Naomi Ori
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture and The Otto Warburg Minerva Center for Agricultural Biotechnology, Hebrew University, P.O. Box 12, Rehovot, 76100, Israel
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22
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Taylor-Teeples M, Lanctot A, Nemhauser JL. As above, so below: Auxin's role in lateral organ development. Dev Biol 2016; 419:156-164. [PMID: 26994944 DOI: 10.1016/j.ydbio.2016.03.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/14/2016] [Accepted: 03/15/2016] [Indexed: 02/02/2023]
Abstract
Organogenesis requires the coordination of many highly-regulated developmental processes, including cell fate determination, cell division and growth, and cell-cell communication. For tissue- and organ-scale coordination, a network of regulators enables molecular events in individual cells to translate into multicellular changes in structure and functional capacity. One recurrent theme in plant developmental networks is a central role for plant hormones, especially auxin. Here, we focus first on describing recent advances in understanding lateral root development, one of the best-studied examples of auxin-mediated organogenesis. We then use this framework to examine the parallel process of emergence of lateral organs in the shoot-a process called phyllotaxy. This comparison reveals a high degree of conservation, highlighting auxin's pivotal role determining overall plant architecture.
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Affiliation(s)
| | - Amy Lanctot
- Department of Biology, University of Washington, Seattle, WA 98195, USA.
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23
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Corso M, Vannozzi A, Ziliotto F, Zouine M, Maza E, Nicolato T, Vitulo N, Meggio F, Valle G, Bouzayen M, Müller M, Munné-Bosch S, Lucchin M, Bonghi C. Grapevine Rootstocks Differentially Affect the Rate of Ripening and Modulate Auxin-Related Genes in Cabernet Sauvignon Berries. FRONTIERS IN PLANT SCIENCE 2016; 7:69. [PMID: 26904046 PMCID: PMC4746306 DOI: 10.3389/fpls.2016.00069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 01/15/2016] [Indexed: 05/06/2023]
Abstract
In modern viticulture, grafting commercial grapevine varieties on interspecific rootstocks is a common practice required for conferring resistance to many biotic and abiotic stresses. Nevertheless, the use of rootstocks to gain these essential traits is also known to impact grape berry development and quality, although the underlying mechanisms are still poorly understood. In grape berries, the onset of ripening (véraison) is regulated by a complex network of mobile signals including hormones such as auxins, ethylene, abscisic acid, and brassinosteroids. Recently, a new rootstock, designated M4, was selected based on its enhanced tolerance to water stress and medium vigor. This study investigates the effect of M4 on Cabernet Sauvignon (CS) berry development in comparison to the commercial 1103P rootstock. Physical and biochemical parameters showed that the ripening rate of CS berries is faster when grafted onto M4. A multifactorial analysis performed on mRNA-Seq data obtained from skin and pulp of berries grown in both graft combinations revealed that genes controlling auxin action (ARF and Aux/IAA) represent one of main categories affected by the rootstock genotype. Considering that the level of auxin tightly regulates the transcription of these genes, we investigated the behavior of the main gene families involved in auxin biosynthesis and conjugation. Molecular and biochemical analyses confirmed a link between the rate of berry development and the modulation of auxin metabolism. Moreover, the data indicate that this phenomenon appears to be particularly pronounced in skin tissue in comparison to the flesh.
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Affiliation(s)
- Massimiliano Corso
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
- Centro Interdipartimentale per la Ricerca in Viticoltura e Enologia, University of PadovaConegliano, Italy
| | - Alessandro Vannozzi
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
- Centro Interdipartimentale per la Ricerca in Viticoltura e Enologia, University of PadovaConegliano, Italy
| | - Fiorenza Ziliotto
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
| | - Mohamed Zouine
- Genomics and Biotechnology of Fruit Laboratory, Institut National Polytechnique de ToulouseToulouse, France
| | - Elie Maza
- Genomics and Biotechnology of Fruit Laboratory, Institut National Polytechnique de ToulouseToulouse, France
| | - Tommaso Nicolato
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
| | - Nicola Vitulo
- Centro di Ricerca Interdipartimentale per le Biotecnologie Innovative, University of PadovaPadova, Italy
| | - Franco Meggio
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
- Centro Interdipartimentale per la Ricerca in Viticoltura e Enologia, University of PadovaConegliano, Italy
| | - Giorgio Valle
- Centro di Ricerca Interdipartimentale per le Biotecnologie Innovative, University of PadovaPadova, Italy
| | - Mondher Bouzayen
- Genomics and Biotechnology of Fruit Laboratory, Institut National Polytechnique de ToulouseToulouse, France
| | - Maren Müller
- Department of Vegetal Biology, University of BarcelonaBarcelona, Spain
| | - Sergi Munné-Bosch
- Department of Vegetal Biology, University of BarcelonaBarcelona, Spain
| | - Margherita Lucchin
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
- Centro Interdipartimentale per la Ricerca in Viticoltura e Enologia, University of PadovaConegliano, Italy
| | - Claudio Bonghi
- Department of Agronomy, Food, Natural resources, Animals and Environment, University of Padova AgripolisLegnaro, Italy
- Centro Interdipartimentale per la Ricerca in Viticoltura e Enologia, University of PadovaConegliano, Italy
- *Correspondence: Claudio Bonghi
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Chen J, Mao L, Lu W, Ying T, Luo Z. Transcriptome profiling of postharvest strawberry fruit in response to exogenous auxin and abscisic acid. PLANTA 2016; 243:183-97. [PMID: 26373937 DOI: 10.1007/s00425-015-2402-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 09/01/2015] [Indexed: 05/09/2023]
Abstract
Auxin and abscisic acid regulate strawberry fruit ripening and senescence through cross-talk of their signal transduction pathways that further modulate the structural genes related to physico-chemical properties of fruit. The physiological and transcriptomic changes in harvested strawberry fruits in responses to IAA, ABA and their combination were analyzed. Exogenous IAA delayed the ripening process of strawberries after harvest while ABA promoted the postharvest ripening. However, treatment with a combination of IAA and ABA did not slow down nor accelerate the postharvest ripening in the strawberry fruits. At the molecular level, exogenous IAA up regulated the expressions of genes related to IAA signaling, including AUX/IAA, ARF, TOPLESS and genes encoding E3 ubiquitin protein ligase and annexin, and down regulated genes related to pectin depolymerization, cell wall degradation, sucrose and anthocyanin biosyntheses. In contrast, exogenous ABA induced genes related to fruit softening, and genes involved in signaling pathways including SKP1, HSPs, CK2, and SRG1. Comparison of transcriptomes in responses to individual treatments with IAA or ABA or the combination revealed that there were cooperative and antagonistic actions between IAA and ABA in fruit. However, 17% of the differentially expressed unigenes in response to the combination of IAA and ABA were unique and were not found in those unigenes responding to either IAA or ABA alone. The analyses also found that receptor-like kinases and ubiquitin ligases responded to both IAA and ABA, which seemed to play a pivotal role in both hormones' signaling pathways and thus might be the cross-talk points of both hormones.
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Affiliation(s)
- Jingxin Chen
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory of Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, 310058, China.
| | - Linchun Mao
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory of Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, 310058, China.
| | - Wenjing Lu
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory of Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, 310058, China
| | - Tiejin Ying
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory of Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, 310058, China
| | - Zisheng Luo
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory of Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, 310058, China
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25
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de Wit M, Ljung K, Fankhauser C. Contrasting growth responses in lamina and petiole during neighbor detection depend on differential auxin responsiveness rather than different auxin levels. THE NEW PHYTOLOGIST 2015; 208:198-209. [PMID: 25963518 DOI: 10.1111/nph.13449] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 04/03/2015] [Indexed: 05/04/2023]
Abstract
Foliar shade triggers rapid growth of specific structures that facilitate access of the plant to direct sunlight. In leaves of many plant species, this growth response is complex because, although shade triggers the elongation of petioles, it reduces the growth of the lamina. How the same external cue leads to these contrasting growth responses in different parts of the leaf is not understood. Using mutant analysis, pharmacological treatment and gene expression analyses, we investigated the role of PHYTOCHROME INTERACTING FACTOR7 (PIF7) and the growth-promoting hormone auxin in these contrasting leaf growth responses. Both petiole elongation and lamina growth reduction are dependent on PIF7. The induction of auxin production is both necessary and sufficient to induce opposite growth responses in petioles vs lamina. However, these contrasting growth responses are not caused by different auxin concentrations in the two leaf parts. Our work suggests that a transient increase in auxin levels triggers tissue-specific growth responses in different leaf parts. We provide evidence suggesting that this may be caused by the different sensitivity to auxin in the petiole vs the blade and by tissue-specific gene expression.
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Affiliation(s)
- Mieke de Wit
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - Karin Ljung
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Christian Fankhauser
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, CH-1015, Lausanne, Switzerland
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Turchi L, Baima S, Morelli G, Ruberti I. Interplay of HD-Zip II and III transcription factors in auxin-regulated plant development. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:5043-53. [PMID: 25911742 DOI: 10.1093/jxb/erv174] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The homeodomain-leucine zipper (HD-Zip) class of transcription factors is unique to plants. HD-Zip proteins bind to DNA exclusively as dimers recognizing dyad symmetric sequences and act as positive or negative regulators of gene expression. On the basis of sequence homology in the HD-Zip DNA-binding domain, HD-Zip proteins have been grouped into four families (HD-Zip I-IV). Each HD-Zip family can be further divided into subfamilies containing paralogous genes that have arisen through genome duplication. Remarkably, all the members of the HD-Zip IIγ and -δ clades are regulated by light quality changes that induce in the majority of the angiosperms the shade-avoidance response, a process regulated at multiple levels by auxin. Intriguingly, it has recently emerged that, apart from their function in shade avoidance, the HD-Zip IIγ and -δ transcription factors control several auxin-regulated developmental processes, including apical embryo patterning, lateral organ polarity, and gynoecium development, in a white-light environment. This review presents recent advances in our understanding of HD-Zip II protein function in plant development, with particular emphasis on the impact of loss-of-function HD-Zip II mutations on auxin distribution and response. The review also describes evidence demonstrating that HD-Zip IIγ and -δ genes are directly and positively regulated by HD-Zip III transcription factors, primary determinants of apical shoot development, known to control the expression of several auxin biosynthesis, transport, and response genes. Finally, the interplay between HD-Zip II and III transcription factors in embryo apical patterning and organ polarity is discussed.
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Affiliation(s)
- L Turchi
- Institute of Molecular Biology and Pathology, National Research Council, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - S Baima
- Food and Nutrition Research Centre, Agricultural Research Council, Via Ardeatina 546, 00178 Rome, Italy
| | - G Morelli
- Food and Nutrition Research Centre, Agricultural Research Council, Via Ardeatina 546, 00178 Rome, Italy
| | - I Ruberti
- Institute of Molecular Biology and Pathology, National Research Council, Piazzale Aldo Moro 5, 00185 Rome, Italy
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27
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Konrad SSA, Ott T. Molecular principles of membrane microdomain targeting in plants. TRENDS IN PLANT SCIENCE 2015; 20:351-61. [PMID: 25936559 DOI: 10.1016/j.tplants.2015.03.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 05/19/2023]
Abstract
Plasma membranes (PMs) are heterogeneous lipid bilayers comprising diverse subdomains. These sites can be labeled by various proteins in vivo and may serve as hotspots for signal transduction. They are found at apical, basal, and lateral membranes of polarized cells, at cell equatorial planes, or almost isotropically distributed throughout the PM. Recent advances in imaging technologies and understanding of mechanisms that allow proteins to target specific sites in PMs have provided insights into the dynamics and complexity of their specific segregation. Here we present a comprehensive overview of the different types of membrane microdomain and describe the molecular modes that determine site-directed targeting of membrane-resident proteins at the PM.
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Affiliation(s)
- Sebastian S A Konrad
- Ludwig-Maximilians-Universität München, Genetics, Großhaderner Str. 2-4, 82152 Planegg-Martinsried, Germany
| | - Thomas Ott
- Ludwig-Maximilians-Universität München, Genetics, Großhaderner Str. 2-4, 82152 Planegg-Martinsried, Germany.
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28
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Gouthu S, Deluc LG. Timing of ripening initiation in grape berries and its relationship to seed content and pericarp auxin levels. BMC PLANT BIOLOGY 2015; 15:46. [PMID: 25848949 PMCID: PMC4340107 DOI: 10.1186/s12870-015-0440-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 01/23/2015] [Indexed: 05/21/2023]
Abstract
BACKGROUND Individual berries in a grape (Vitis vinifera L.) cluster enter the ripening phase at different times leading to an asynchronous cluster in terms of ripening. The factors causing this variable ripening initiation among berries are not known. Because the influence via hormonal communication of the seed on fruit set and growth is well known across fruit species, differences in berry seed content and resultant quantitative or qualitative differences in the hormone signals to the pericarp likely influence the relative timing of ripening initiation among berries of the cluster. RESULTS At the time of the initiation of cluster ripening (véraison), underripe green berries have higher seed content compared to the riper berries and there is a negative correlation between the seed weight-to-berry weight ratio (SB) and the sugar level in berries of a cluster. Auxin levels in seeds relative to the pericarp tissues are two to 12 times higher at pre-ripening stages. The pericarp of berries with high-SB had higher auxin and lower abscisic acid (ABA) levels compared to those with low-SB from two weeks before véraison. In the prevéraison cluster, the expression of auxin-response factor genes was significantly higher in the pericarp of high-SB berries and remained higher until véraison compared to low-SB berries. The expression level of auxin-biosynthetic genes in the pericarp was the same between both berry groups based upon similar expression activity of YUC genes that are rate-limiting factors in auxin biosynthesis. On the other hand, in low-SB berries, the expression of ABA-biosynthetic and ABA-inducible NCED and MYB genes was higher even two weeks before véraison. CONCLUSIONS Differences in the relative seed content among berries plays a major role in the timing of ripening initiation. Towards the end of berry maturation phase, low and high levels of auxin are observed in the pericarp of low- and high-SB berries, respectively. This results in higher auxin-signaling activity that lasts longer in the pericarp of high-SB berries. In contrast, in low-SB berries, concomitant with an earlier decrease of auxin level, the features of ripening initiation, such as increases in ABA and sugar accumulation begin earlier.
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Affiliation(s)
- Satyanarayana Gouthu
- Department of Horticulture, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331 USA
| | - Laurent G Deluc
- Department of Horticulture, College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331 USA
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29
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Abstract
Plants use auxin to relay critical information that shapes their growth and development. Auxin perception and transcriptional activation are mediated by the degradation of Aux/IAA repressor proteins. Degradation of Aux/IAAs relieves repression on Auxin Response Factors (ARFs), which bind DNA sequences called Auxin Response Elements (AuxREs). In most higher plant genomes, multiple paralogs exist for each part of the auxin nuclear signaling pathway. This potential combinatorial diversity in signaling pathways likely contributes to the myriad of context-specific responses to auxin. Recent structures of several domains from ARF proteins have exposed new modes of ARF dimerization, new models for ARF-AuxRE specificity, and the strong likelihood of larger order complexes formed by ARF and Aux/IAA homo- and heteromultimerization. Preliminary experiments support a role for these novel interactions in planta, further increasing the potential architectural complexity of this seemingly simple pathway.
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30
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Guseman JM, Hellmuth A, Lanctot A, Feldman TP, Moss BL, Klavins E, Calderón Villalobos LIA, Nemhauser JL. Auxin-induced degradation dynamics set the pace for lateral root development. Development 2015; 142:905-9. [PMID: 25633353 DOI: 10.1242/dev.117234] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Auxin elicits diverse cell behaviors through a simple nuclear signaling pathway initiated by degradation of Aux/IAA co-repressors. Our previous work revealed that members of the large Arabidopsis Aux/IAA family exhibit a range of degradation rates in synthetic contexts. However, it remained an unresolved issue whether differences in Aux/IAA turnover rates played a significant role in plant responses to auxin. Here, we use the well-established model of lateral root development to directly test the hypothesis that the rate of auxin-induced Aux/IAA turnover sets the pace for auxin-regulated developmental events. We did this by generating transgenic plants expressing degradation rate variants of IAA14, a crucial determinant of lateral root initiation. Progression through the well-established stages of lateral root development was strongly correlated with the engineered rates of IAA14 turnover, leading to the conclusion that Aux/IAAs are auxin-initiated timers that synchronize developmental transitions.
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Affiliation(s)
- Jessica M Guseman
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Antje Hellmuth
- Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany
| | - Amy Lanctot
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Tamar P Feldman
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Britney L Moss
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - Eric Klavins
- Department of Electrical Engineering, University of Washington, Seattle, WA 98195, USA
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31
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Mironova VV, Omelyanchuk NA, Wiebe DS, Levitsky VG. Computational analysis of auxin responsive elements in the Arabidopsis thaliana L. genome. BMC Genomics 2014; 15 Suppl 12:S4. [PMID: 25563792 PMCID: PMC4331925 DOI: 10.1186/1471-2164-15-s12-s4] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Auxin responsive elements (AuxRE) were found in upstream regions of target genes for ARFs (Auxin response factors). While Chip-seq data for most of ARFs are still unavailable, prediction of potential AuxRE is restricted by consensus models that detect too many false positive sites. Using sequence analysis of experimentally proven AuxREs, we revealed both an extended nucleotide context pattern for AuxRE itself and three distinct types of its coupling motifs (Y-patch, AuxRE-like, and ABRE-like), which together with AuxRE may form the composite elements. Computational analysis of the genome-wide distribution of the predicted AuxREs and their impact on auxin responsive gene expression allowed us to conclude that: (1) AuxREs are enriched around the transcription start site with the maximum density in 5'UTR; (2) AuxREs mediate auxin responsive up-regulation, not down-regulation. (3) Directly oriented single AuxREs and reverse multiple AuxREs are mostly associated with auxin responsiveness. In the composite AuxRE elements associated with auxin response, ABRE-like and Y-patch are 5'-flanking or overlapping AuxRE, whereas AuxRE-like motif is 3'-flanking. The specificity in location and orientation of the coupling elements suggests them as potential binding sites for ARFs partners.
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32
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Zhang L, Peng Y, Wei X, Dai Y, Yuan D, Lu Y, Pan Y, Zhu Z. Small RNAs as important regulators for the hybrid vigour of super-hybrid rice. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:5989-6002. [PMID: 25129133 PMCID: PMC4203131 DOI: 10.1093/jxb/eru337] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Heterosis is an important biological phenomenon; however, the role of small RNA (sRNA) in heterosis of hybrid rice remains poorly described. Here, we performed sRNA profiling of F1 super-hybrid rice LYP9 and its parents using high-throughput sequencing technology, and identified 355 distinct mature microRNAs and trans-acting small interfering RNAs, 69 of which were differentially expressed sRNAs (DES) between the hybrid and the mid-parental value. Among these, 34 DES were predicted to target 176 transcripts, of which 112 encoded 94 transcription factors. Further analysis showed that 67.6% of DES expression levels were negatively correlated with their target mRNAs either in flag leaves or panicles. The target genes of DES were significantly enriched in some important biological processes, including the auxin signalling pathway, in which existed a regulatory network mediated by DES and their targets, closely associated with plant growth and development. Overall, 20.8% of DES and their target genes were significantly enriched in quantitative trait loci of small intervals related to important rice agronomic traits including growth vigour, grain yield, and plant architecture, suggesting that the interaction between sRNAs and their targets contributes to the heterotic phenotypes of hybrid rice. Our findings revealed that sRNAs might play important roles in hybrid vigour of super-hybrid rice by regulating their target genes, especially in controlling the auxin signalling pathway. The above finding provides a novel insight into the molecular mechanism of heterosis.
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Affiliation(s)
- Lei Zhang
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Yonggang Peng
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Xiaoli Wei
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Yan Dai
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Dawei Yuan
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Yufei Lu
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Yangyang Pan
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
| | - Zhen Zhu
- State Key Laboratory of Plant Genomics and National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing 100101, PR China
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33
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Wang R, Estelle M. Diversity and specificity: auxin perception and signaling through the TIR1/AFB pathway. CURRENT OPINION IN PLANT BIOLOGY 2014; 21:51-58. [PMID: 25032902 PMCID: PMC4294414 DOI: 10.1016/j.pbi.2014.06.006] [Citation(s) in RCA: 165] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/15/2014] [Indexed: 05/19/2023]
Abstract
Auxin is a versatile plant hormone that plays an essential role in most aspects of plant growth and development. Auxin regulates various growth processes by modulating gene transcription through a SCF(TIR1/AFB)-Aux/IAA-ARF nuclear signaling module. Recent work has generated clues as to how multiple layers of regulation of the auxin signaling components may result in diverse and specific response outputs. In particular, interaction and structural studies of key auxin signaling proteins have produced novel insights into the molecular basis of auxin-regulated transcription and may lead to a refined auxin signaling model.
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Affiliation(s)
- Renhou Wang
- Section of Cell and Developmental Biology and Howard Hughes Medical Institute, UCSD, La Jolla, CA 92093, United States
| | - Mark Estelle
- Section of Cell and Developmental Biology and Howard Hughes Medical Institute, UCSD, La Jolla, CA 92093, United States.
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34
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Abstract
Plants are permanently situated in a fixed location and thus are well adapted to sense and respond to environmental stimuli and developmental cues. At the cellular level, several of these responses require delicate adjustments that affect the activity and steady-state levels of plasma membrane proteins. These adjustments involve both vesicular transport to the plasma membrane and protein internalization via endocytic sorting. A substantial part of our current knowledge of plant plasma membrane protein sorting is based on studies of PIN-FORMED (PIN) auxin transport proteins, which are found at distinct plasma membrane domains and have been implicated in directional efflux of the plant hormone auxin. Here, we discuss the mechanisms involved in establishing such polar protein distributions, focusing on PINs and other key plant plasma membrane proteins, and we highlight the pathways that allow for dynamic adjustments in protein distribution and turnover, which together constitute a versatile framework that underlies the remarkable capabilities of plants to adjust growth and development in their ever-changing environment.
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Affiliation(s)
- Christian Luschnig
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna (BOKU), Muthgasse 18, Vienna 1190, Austria
| | - Grégory Vert
- Institut des Sciences du Végétal, CNRS UPR 2355, 1 Avenue de la Terrasse, Bâtiment 23A, Gif-sur-Yvette 91190, France
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35
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Chao WS, Doğramaci M, Anderson JV, Foley ME, Horvath DP. The resemblance and disparity of gene expression in dormant and non-dormant seeds and crown buds of leafy spurge (Euphorbia esula). BMC PLANT BIOLOGY 2014; 14:216. [PMID: 25112962 PMCID: PMC4256794 DOI: 10.1186/s12870-014-0216-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/04/2014] [Indexed: 05/03/2023]
Abstract
BACKGROUND Leafy spurge (Euphorbia esula L.) is a herbaceous perennial weed and dormancy in both buds and seeds is an important survival mechanism. Bud dormancy in leafy spurge exhibits three well-defined phases of para-, endo- and ecodormancy; however, seed dormancy for leafy spurge is classified as physiological dormancy that requires after-ripening and alternating temperature for maximal germination. Overlaps in transcriptome profiles between different phases of bud and seed dormancy have not been determined. Thus, we compared various phases of dormancy between seeds and buds to identify common genes and molecular processes, which should provide new insights about common regulators of dormancy. RESULTS Cluster analysis of expression profiles for 201 selected genes indicated bud and seed samples clustered separately. Direct comparisons between buds and seeds are additionally complicated since seeds incubated at a constant temperature of 20°C for 21 days (21d C) could be considered paradormant (Para) because seeds may be inhibited by endosperm-generated signals, or ecodormant (Eco) because seeds germinate after being subjected to alternating temperature of 20:30°C. Since direct comparisons in gene expression between buds and seeds were problematic, we instead examined commonalities in differentially-expressed genes associated with different phases of dormancy. Comparison between buds and seeds ('Para to Endo buds' and '21d C to 1d C seeds'), using endodormant buds (Endo) and dormant seeds (1d C) as common baselines, identified transcripts associated with cell cycle (HisH4), stress response/transcription factors (ICE2, ERFB4/ABR1), ABA and auxin response (ABA1, ARF1, IAA7, TFL1), carbohydrate/protein degradation (GAPDH_1), and transport (ABCB2). Comparison of transcript abundance for the 'Eco to Endo buds' and '21d C to 1d C seeds' identified transcripts associated with ABA response (ATEM6), auxin response (ARF1), and cell cycle (HisH4). These results indicate that the physiological state of 21d C seeds is more analogous to paradormant buds than that of ecodormant buds. CONCLUSION Combined results indicate that common molecular mechanisms associated with dormancy transitions of buds and seeds involve processes associated with ABA and auxin signaling and transport, cell cycle, and AP2/ERF transcription factors or their up-stream regulators.
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Affiliation(s)
- Wun S Chao
- USDA-Agricultural Research Service, Biosciences Research Lab, Sunflower and Plant Biology Research Unit, 1605 Albrecht Boulevard N, Fargo, ND 58102 USA
| | - Münevver Doğramaci
- USDA-Agricultural Research Service, Biosciences Research Lab, Sunflower and Plant Biology Research Unit, 1605 Albrecht Boulevard N, Fargo, ND 58102 USA
| | - James V Anderson
- USDA-Agricultural Research Service, Biosciences Research Lab, Sunflower and Plant Biology Research Unit, 1605 Albrecht Boulevard N, Fargo, ND 58102 USA
| | - Michael E Foley
- USDA-Agricultural Research Service, Biosciences Research Lab, Sunflower and Plant Biology Research Unit, 1605 Albrecht Boulevard N, Fargo, ND 58102 USA
| | - David P Horvath
- USDA-Agricultural Research Service, Biosciences Research Lab, Sunflower and Plant Biology Research Unit, 1605 Albrecht Boulevard N, Fargo, ND 58102 USA
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DePaoli HC, Borland AM, Tuskan GA, Cushman JC, Yang X. Synthetic biology as it relates to CAM photosynthesis: challenges and opportunities. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:3381-93. [PMID: 24567493 DOI: 10.1093/jxb/eru038] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
To meet future food and energy security needs, which are amplified by increasing population growth and reduced natural resource availability, metabolic engineering efforts have moved from manipulating single genes/proteins to introducing multiple genes and novel pathways to improve photosynthetic efficiency in a more comprehensive manner. Biochemical carbon-concentrating mechanisms such as crassulacean acid metabolism (CAM), which improves photosynthetic, water-use, and possibly nutrient-use efficiency, represent a strategic target for synthetic biology to engineer more productive C3 crops for a warmer and drier world. One key challenge for introducing multigene traits like CAM onto a background of C3 photosynthesis is to gain a better understanding of the dynamic spatial and temporal regulatory events that underpin photosynthetic metabolism. With the aid of systems and computational biology, vast amounts of experimental data encompassing transcriptomics, proteomics, and metabolomics can be related in a network to create dynamic models. Such models can undergo simulations to discover key regulatory elements in metabolism and suggest strategic substitution or augmentation by synthetic components to improve photosynthetic performance and water-use efficiency in C3 crops. Another key challenge in the application of synthetic biology to photosynthesis research is to develop efficient systems for multigene assembly and stacking. Here, we review recent progress in computational modelling as applied to plant photosynthesis, with attention to the requirements for CAM, and recent advances in synthetic biology tool development. Lastly, we discuss possible options for multigene pathway construction in plants with an emphasis on CAM-into-C3 engineering.
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Affiliation(s)
- Henrique C DePaoli
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA
| | - Anne M Borland
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA School of Biology, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK
| | - Gerald A Tuskan
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA
| | - John C Cushman
- Department of Biochemistry and Molecular Biology, MS330, University of Nevada, Reno, NV 89557-0330, USA
| | - Xiaohan Yang
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6422, USA
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Abstract
Auxin influences nearly every aspect of plant biology through a simple signaling pathway; however, it remains unclear how much of the diversity in auxin effects is explained by variation in the core signaling components and which properties of these components may contribute to diversification in response dynamics. Here, we recapitulated the entire Arabidopsis thaliana forward nuclear auxin signal transduction pathway in Saccharomyces cerevisiae to test whether signaling module composition enables tuning of the dynamic response. Sensitivity analysis guided by a small mathematical model revealed the centrality of auxin/indole-3-acetic acid (Aux/IAA) transcriptional corepressors in controlling response dynamics and highlighted the strong influence of natural variation in Aux/IAA degradation rates on circuit performance. When the basic auxin response circuit was expanded to include multiple Aux/IAAs, we found that dominance relationships between coexpressed Aux/IAAs were sufficient to generate distinct response modules similar to those seen during plant development. Our work provides a new method for dissecting auxin signaling and demonstrates the key role of Aux/IAAs in tuning auxin response dynamics.
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38
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Del Pozo JC, Manzano C. Auxin and the ubiquitin pathway. Two players-one target: the cell cycle in action. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2617-2632. [PMID: 24215077 DOI: 10.1093/jxb/ert363] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Plants are sessile organisms that have to adapt their growth to the surrounding environment. Concomitant with this adaptation capability, they have adopted a post-embryonic development characterized by continuous growth and differentiation abilities. Constant growth is based on the potential of stem cells to divide almost incessantly and on a precise balance between cell division and cell differentiation. This balance is influenced by environmental conditions and by the genetic information of the cell. Among the internal cues, the cross-talk between different hormonal signalling pathways is essential to control this division/differentiation equilibrium. Auxin, one of the most important plant hormones, regulates cell division and differentiation, among many other processes. Amazing advances in auxin signal transduction at the molecular level have been reported, but how this signalling is connected to the cell cycle is, so far, not well known. Auxin signalling involves the auxin-dependent degradation of transcription repressors by F-box-containing E3 ligases of ubiquitin. Recently, SKP2A, another F-box protein, was shown to bind auxin and to target cell-cycle repressors for proteolysis, representing a novel mechanism that links auxin to cell division. In this review, a general vision of what is already known and the most recent advances on how auxin signalling connects to cell division and the role of the ubiquitin pathway in plant cell cycle will be covered.
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Affiliation(s)
- Juan C Del Pozo
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - Concepción Manzano
- Centro de Biotecnología y Genómica de Plantas (CBGP) INIA-UPM. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. Campus de Montegancedo, Pozuelo de Alarcón, 28223 Madrid, Spain
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39
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Perrot-Rechenmann C. Auxin Signaling in Plants. Mol Biol 2014. [DOI: 10.1007/978-1-4614-7570-5_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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40
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Gilkerson J, Callis J. A genetic screen for mutants defective in IAA1-LUC degradation in Arabidopsis thaliana reveals an important requirement for TOPOISOMERASE6B in auxin physiology. PLANT SIGNALING & BEHAVIOR 2014; 9:e972207. [PMID: 25482814 PMCID: PMC4622002 DOI: 10.4161/psb.29850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Many plant growth and developmental processes are modulated by the hormone auxin. Auxin-modulated proteolysis of Aux/IAAs, a family of transcriptional repressors, represents a major mode of auxin action. Auxin facilitates the interaction of Aux/IAAs with TIR1/AFB F-box proteins, promoting their ubiquitination by the SCF(TIR1/AFB) ubiquitin E3 ligase leading to subsequent degradation by the 26S proteasome. To identify new genes regulating Aux/IAA proteolysis in Arabidopsis thaliana, we took a genetic approach, identifying individuals with altered degradation of an IAA1-luciferase fusion protein (IAA1-LUC). A mutant with 2-fold slower IAA1-LUC degradation rate compared with wild-type was isolated. Positional cloning identified the mutant as an allele of TOPOISOMERASE6B, named top6b-7. TOP6B encodes a subunit of a plant and archea-specific enzyme regulating endoreduplication, DNA damage repair and transcription in plants. T-DNA insertion alleles (top6b-8 and top6b-9) were also analyzed. top6b-7 seedlings are less sensitive to exogenous auxin than wild-type siblings in primary root growth assays, and experiments with DR5:GUS. Additionally, top6b-7 seedlings have a 40% reduction in the amount of endogenous IAA. These data suggest that increased IAA1-LUC half-life in top6b-7 probably results from a combination of both lower endogenous IAA levels and reduced sensitivity to auxin.
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Affiliation(s)
- Jonathan Gilkerson
- Department of Molecular and Cellular Biology and Plant Biology Graduate Group; University of California; Davis, CA USA
- Current address: Plant Biology Laboratory; Howard Hughes Medical Institute; Salk Institute for Biological Studies; La Jolla, CA USA
| | - Judy Callis
- Department of Molecular and Cellular Biology and Plant Biology Graduate Group; University of California; Davis, CA USA
- Correspondence to: Judy Callis;
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Signaling: Auxin Signaling. Mol Biol 2014. [DOI: 10.1007/978-1-4939-0263-7_15-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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