1
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Pei ZQ, Ma C, Dong CY, Xu TT, Chai CH, Zhu Q, Wang J, Zheng S, Zhang TG. Target of rapamycin coordinates auxin are involved in exogenous melatonin regulated low temperature tolerance in cucumber seedlings. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 215:109055. [PMID: 39182426 DOI: 10.1016/j.plaphy.2024.109055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 07/31/2024] [Accepted: 08/16/2024] [Indexed: 08/27/2024]
Abstract
Low temperature (LT) is an important environmental factor affecting the growth and yield of plants. Melatonin (MT) can effectively enhance the LT tolerance of cucumber. This study found that LT stress induced the expression of Comt1 (caffeic acid O-methyltransferase 1), with the highest expression being about 2-times that of the control. Meanwhile, the content of MT was found to be roughly 63.16% of that in the control samples. Compared with LT treatment alone, exogenous MT pretreatment upregulated the expression levels of TOR (Target of rapamycin), PIN1 (Pin-formed 1), and YUC4 (YUCCA 4), with maximum upregulations reaching approximately 66.67%, 79.32%, and 42.86%, respectively. These results suggest that MT may modulate the tolerance of cucumber seedlings to LT stress by regulating the expression of TOR, PIN1, and YUC4. In addition, co-treatment with AZD-8055 (a TOR inhibitor) or NPA (N-1-naphthylphthalamic acid, an auxin polar transport inhibitor) and MT attenuated MT-induced resistance to LT stress, leading to higher levels of reactive oxygen species (ROS), reduced antioxidant defense capacity, and increased damage to the membrane system in cucumber seedlings. Concurrently, the content of osmoregulatory substances and the photosynthesis decreased. These results demonstrate that both TOR and auxin were required for MT to alleviate LT-induced damage in cucumber. In summary, the present study demonstrates that TOR and auxin signaling synergistically contribute to alleviating LT damage in cucumber seedlings by exogenous MT. These findings help us understand the function of MT and provide insights into the regulatory network of MT that regulates the LT tolerance of plants.
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Affiliation(s)
- Zi-Qi Pei
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Cheng Ma
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Cui-Yun Dong
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Ting-Ting Xu
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Cai-Hong Chai
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Qiao Zhu
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Juan Wang
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Sheng Zheng
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China
| | - Teng-Guo Zhang
- College of Life Sciences, Northwest Normal University, Lanzhou, 730070, China.
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2
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Boix M, Garcia-Rodriguez A, Castillo L, Miró B, Hamilton F, Tolak S, Pérez A, Monte-Bello C, Caldana C, Henriques R. 40S Ribosomal protein S6 kinase integrates daylength perception and growth regulation in Arabidopsis thaliana. PLANT PHYSIOLOGY 2024; 195:3039-3052. [PMID: 38701056 PMCID: PMC11288760 DOI: 10.1093/plphys/kiae254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/29/2024] [Accepted: 04/09/2024] [Indexed: 05/05/2024]
Abstract
Plant growth occurs via the interconnection of cell growth and proliferation in each organ following specific developmental and environmental cues. Therefore, different photoperiods result in distinct growth patterns due to the integration of light and circadian perception with specific Carbon (C) partitioning strategies. In addition, the TARGET OF RAPAMYCIN (TOR) kinase pathway is an ancestral signaling pathway that integrates nutrient information with translational control and growth regulation. Recent findings in Arabidopsis (Arabidopsis thaliana) have shown a mutual connection between the TOR pathway and the circadian clock. However, the mechanistical network underlying this interaction is mostly unknown. Here, we show that the conserved TOR target, the 40S ribosomal protein S6 kinase (S6K) is under circadian and photoperiod regulation both at the transcriptional and post-translational level. Total S6K (S6K1 and S6K2) and TOR-dependent phosphorylated-S6K protein levels were higher during the light period and decreased at dusk especially under short day conditions. Using chemical and genetic approaches, we found that the diel pattern of S6K accumulation results from 26S proteasome-dependent degradation and is altered in mutants lacking the circadian F-box protein ZEITLUPE (ZTL), further strengthening our hypothesis that S6K could incorporate metabolic signals via TOR, which are also under circadian regulation. Moreover, under short days when C/energy levels are limiting, changes in S6K1 protein levels affected starch, sucrose and glucose accumulation and consequently impacted root and rosette growth responses. In summary, we propose that S6K1 constitutes a missing molecular link where day-length perception, nutrient availability and TOR pathway activity converge to coordinate growth responses with environmental conditions.
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Affiliation(s)
- Marc Boix
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, 08193 Barcelona, Spain
| | - Alba Garcia-Rodriguez
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, 08193 Barcelona, Spain
| | - Laia Castillo
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, 08193 Barcelona, Spain
| | - Bernat Miró
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, 08193 Barcelona, Spain
| | - Ferga Hamilton
- School of Biological, Earth and Environmental Sciences, University College Cork, North Mall, Cork T23 N73K, Ireland
- Environmental Research Institute, University College Cork, Cork T23 XE10, Ireland
| | - Sanata Tolak
- School of Biological, Earth and Environmental Sciences, University College Cork, North Mall, Cork T23 N73K, Ireland
- Environmental Research Institute, University College Cork, Cork T23 XE10, Ireland
| | - Adrián Pérez
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, 08193 Barcelona, Spain
| | | | - Camila Caldana
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
| | - Rossana Henriques
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus UAB, 08193 Barcelona, Spain
- School of Biological, Earth and Environmental Sciences, University College Cork, North Mall, Cork T23 N73K, Ireland
- Environmental Research Institute, University College Cork, Cork T23 XE10, Ireland
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3
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Lohmann J, Herzog O, Rosenzweig K, Weingartner M. Thermal adaptation in plants: understanding the dynamics of translation factors and condensates. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4258-4273. [PMID: 38630631 DOI: 10.1093/jxb/erae171] [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: 12/15/2023] [Accepted: 04/16/2024] [Indexed: 04/19/2024]
Abstract
Plants, as sessile organisms, face the crucial challenge of adjusting growth and development with ever-changing environmental conditions. Protein synthesis is the fundamental process that enables growth of all organisms. Since elevated temperature presents a substantial threat to protein stability and function, immediate adjustments of protein synthesis rates are necessary to circumvent accumulation of proteotoxic stress and to ensure survival. This review provides an overview of the mechanisms that control translation under high-temperature stress by the modification of components of the translation machinery in plants, and compares them to yeast and metazoa. Recent research also suggests an important role for cytoplasmic biomolecular condensates, named stress granules, in these processes. Current understanding of the role of stress granules in translational regulation and of the molecular processes associated with translation that might occur within stress granules is also discussed.
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Affiliation(s)
- Julia Lohmann
- Institute of Plant Sciences and Microbiology, University of Hamburg, Ohnhorststrasse 18, 22609 Hamburg, Germany
| | - Oliver Herzog
- Institute of Plant Sciences and Microbiology, University of Hamburg, Ohnhorststrasse 18, 22609 Hamburg, Germany
| | - Kristina Rosenzweig
- Institute of Plant Sciences and Microbiology, University of Hamburg, Ohnhorststrasse 18, 22609 Hamburg, Germany
| | - Magdalena Weingartner
- Institute of Plant Sciences and Microbiology, University of Hamburg, Ohnhorststrasse 18, 22609 Hamburg, Germany
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4
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Hardy EC, Balcerowicz M. Untranslated yet indispensable-UTRs act as key regulators in the environmental control of gene expression. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:4314-4331. [PMID: 38394144 PMCID: PMC11263492 DOI: 10.1093/jxb/erae073] [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: 11/01/2023] [Accepted: 02/22/2024] [Indexed: 02/25/2024]
Abstract
To survive and thrive in a dynamic environment, plants must continuously monitor their surroundings and adjust their development and physiology accordingly. Changes in gene expression underlie these developmental and physiological adjustments, and are traditionally attributed to widespread transcriptional reprogramming. Growing evidence, however, suggests that post-transcriptional mechanisms also play a vital role in tailoring gene expression to a plant's environment. Untranslated regions (UTRs) act as regulatory hubs for post-transcriptional control, harbouring cis-elements that affect an mRNA's processing, localization, translation, and stability, and thereby tune the abundance of the encoded protein. Here, we review recent advances made in understanding the critical function UTRs exert in the post-transcriptional control of gene expression in the context of a plant's abiotic environment. We summarize the molecular mechanisms at play, present examples of UTR-controlled signalling cascades, and discuss the potential that resides within UTRs to render plants more resilient to a changing climate.
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Affiliation(s)
- Emma C Hardy
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Dundee DD2 5DA, UK
| | - Martin Balcerowicz
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Dundee DD2 5DA, UK
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5
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Chen Q, Zhou S, Qu M, Yang Y, Chen Q, Meng X, Fan H. Cucumber (Cucumis sativus L.) translationally controlled tumor protein interacts with CsRab11A and promotes activation of target of rapamycin in response to Podosphaera xanthii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 119:332-347. [PMID: 38700955 DOI: 10.1111/tpj.16766] [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: 11/07/2023] [Revised: 03/12/2024] [Accepted: 03/26/2024] [Indexed: 05/05/2024]
Abstract
The target of rapamycin (TOR) kinase serves as a central regulator that integrates nutrient and energy signals to orchestrate cellular and organismal physiology in both animals and plants. Despite significant advancements having been made in understanding the molecular and cellular functions of plant TOR kinases, the upstream regulators that modulate TOR activity are not yet fully elucidated. In animals, the translationally controlled tumor protein (TCTP) is recognized as a key player in TOR signaling. This study reveals that two TCTP isoforms from Cucumis sativus, when introduced into Arabidopsis, are instrumental in balancing growth and defense mechanisms against the fungal pathogen Golovinomyces cichoracearum. We hypothesize that plant TCTPs act as upstream regulators of TOR in response to powdery mildew caused by Podosphaera xanthii in Cucumis. Our research further uncovers a stable interaction between CsTCTP and a small GTPase, CsRab11A. Transient transformation assays indicate that CsRab11A is involved in the defense against P. xanthii and promotes the activation of TOR signaling through CsTCTP. Moreover, our findings demonstrate that the critical role of TOR in plant disease resistance is contingent upon its regulated activity; pretreatment with a TOR inhibitor (AZD-8055) enhances cucumber plant resistance to P. xanthii, while pretreatment with a TOR activator (MHY-1485) increases susceptibility. These results suggest a sophisticated adaptive response mechanism in which upstream regulators, CsTCTP and CsRab11A, coordinate to modulate TOR function in response to P. xanthii, highlighting a novel aspect of plant-pathogen interactions.
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Affiliation(s)
- Qiumin Chen
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
| | - Shuang Zhou
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
| | - Mengqi Qu
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
| | - Yun Yang
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
| | - Qinglei Chen
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
| | - Xiangnan Meng
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
- Key Laboratory of Agricultural Biotechnology of Liaoning Province, Shenyang Agricultural University, Shenyang, China
| | - Haiyan Fan
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China
- Key Laboratory of Protected Horticulture of Ministry of Education, Shenyang Agricultural University, Shenyang, China
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6
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Artins A, Martins MCM, Meyer C, Fernie AR, Caldana C. Sensing and regulation of C and N metabolism - novel features and mechanisms of the TOR and SnRK1 signaling pathways. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:1268-1280. [PMID: 38349940 DOI: 10.1111/tpj.16684] [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: 12/16/2022] [Revised: 01/25/2024] [Accepted: 02/02/2024] [Indexed: 02/15/2024]
Abstract
Carbon (C) and nitrogen (N) metabolisms are tightly integrated to allow proper plant growth and development. Photosynthesis is dependent on N invested in chlorophylls, enzymes, and structural components of the photosynthetic machinery, while N uptake and assimilation rely on ATP, reducing equivalents, and C-skeletons provided by photosynthesis. The direct connection between N availability and photosynthetic efficiency allows the synthesis of precursors for all metabolites and building blocks in plants. Thus, the capacity to sense and respond to sudden changes in C and N availability is crucial for plant survival and is mediated by complex yet efficient signaling pathways such as TARGET OF RAPAMYCIN (TOR) and SUCROSE-NON-FERMENTING-1-RELATED PROTEIN KINASE 1 (SnRK1). In this review, we present recent advances in mechanisms involved in sensing C and N status as well as identifying current gaps in our understanding. We finally attempt to provide new perspectives and hypotheses on the interconnection of diverse signaling pathways that will allow us to understand the integration and orchestration of the major players governing the regulation of the CN balance.
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Affiliation(s)
- Anthony Artins
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Golm, Germany
| | - Marina C M Martins
- in Press - Scientific Consulting and Communication Services, 05089-030, São Paulo, São Paulo, Brazil
| | - Christian Meyer
- Institut Jean-Pierre Bourgin (IJPB), INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Golm, Germany
| | - Camila Caldana
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Golm, Germany
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7
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Hernández-Esquivel AA, Torres-Olmos JA, Méndez-Gómez M, Castro-Mercado E, Flores-Cortéz I, Peña-Uribe CA, Campos-García J, López-Bucio J, Reyes-de la Cruz H, Valencia-Cantero E, García-Pineda E. Hydrogen peroxide modulates the expression of the target of rapamycin (TOR) and cell division in Arabidopsis thaliana. PROTOPLASMA 2024:10.1007/s00709-024-01959-6. [PMID: 38802622 DOI: 10.1007/s00709-024-01959-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 05/15/2024] [Indexed: 05/29/2024]
Abstract
Hydrogen peroxide (H2O2) is naturally produced by plant cells during normal development and serves as a messenger that regulates cell metabolism. Despite its importance, the relationship between hydrogen peroxide and the target of rapamycin (TOR) pathway, as well as its impact on cell division, has been poorly analyzed. In this study, we explore the interaction of H2O2 with TOR, a serine/threonine protein kinase that plays a central role in controlling cell growth, size, and metabolism in Arabidopsis thaliana. By applying two concentrations of H2O2 exogenously (0.5 and 1 mM), we could correlate developmental traits, such as primary root growth, lateral root formation, and fresh weight, with the expression of the cell cycle gene CYCB1;1, as well as TOR expression. When assessing the expression of the ribosome biogenesis-related gene RPS27B, an increase of 94.34% was noted following exposure to 1 mM H2O2 treatment. This increase was suppressed by the TOR inhibitor torin 2. The elimination of H2O2 accumulation with ascorbic acid (AA) resulted in decreased cell division as well as TOR expression. The potential molecular mechanisms associated with the effects of H2O2 on the cell cycle and TOR expression in roots are discussed in the context of the results.
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Affiliation(s)
- Alma Alejandra Hernández-Esquivel
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Jorge Alejandro Torres-Olmos
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Manuel Méndez-Gómez
- Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), Unidad Irapuato, 36821, Irapuato, Gto., México
| | - Elda Castro-Mercado
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Idolina Flores-Cortéz
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - César Arturo Peña-Uribe
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Jesús Campos-García
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - José López-Bucio
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Homero Reyes-de la Cruz
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Eduardo Valencia-Cantero
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México
| | - Ernesto García-Pineda
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Edif. B1, Morelia, Michoacán, CP 58040, México.
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8
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Wu HYL, Jen J, Hsu PY. What, where, and how: Regulation of translation and the translational landscape in plants. THE PLANT CELL 2024; 36:1540-1564. [PMID: 37437121 PMCID: PMC11062462 DOI: 10.1093/plcell/koad197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 07/14/2023]
Abstract
Translation is a crucial step in gene expression and plays a vital role in regulating various aspects of plant development and environmental responses. It is a dynamic and complex program that involves interactions between mRNAs, transfer RNAs, and the ribosome machinery through both cis- and trans-regulation while integrating internal and external signals. Translational control can act in a global (transcriptome-wide) or mRNA-specific manner. Recent advances in genome-wide techniques, particularly ribosome profiling and proteomics, have led to numerous exciting discoveries in both global and mRNA-specific translation. In this review, we aim to provide a "primer" that introduces readers to this fascinating yet complex cellular process and provide a big picture of how essential components connect within the network. We begin with an overview of mRNA translation, followed by a discussion of the experimental approaches and recent findings in the field, focusing on unannotated translation events and translational control through cis-regulatory elements on mRNAs and trans-acting factors, as well as signaling networks through 3 conserved translational regulators TOR, SnRK1, and GCN2. Finally, we briefly touch on the spatial regulation of mRNAs in translational control. Here, we focus on cytosolic mRNAs; translation in organelles and viruses is not covered in this review.
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Affiliation(s)
- Hsin-Yen Larry Wu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Joey Jen
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Polly Yingshan Hsu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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9
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Rawat SS, Laxmi A. Sugar signals pedal the cell cycle! FRONTIERS IN PLANT SCIENCE 2024; 15:1354561. [PMID: 38562561 PMCID: PMC10982403 DOI: 10.3389/fpls.2024.1354561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 02/19/2024] [Indexed: 04/04/2024]
Abstract
Cell cycle involves the sequential and reiterative progression of important events leading to cell division. Progression through a specific phase of the cell cycle is under the control of various factors. Since the cell cycle in multicellular eukaryotes responds to multiple extracellular mitogenic cues, its study in higher forms of life becomes all the more important. One such factor regulating cell cycle progression in plants is sugar signalling. Because the growth of organs depends on both cell growth and proliferation, sugars sensing and signalling are key control points linking sugar perception to regulation of downstream factors which facilitate these key developmental transitions. However, the basis of cell cycle control via sugars is intricate and demands exploration. This review deals with the information on sugar and TOR-SnRK1 signalling and how they manoeuvre various events of the cell cycle to ensure proper growth and development.
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Affiliation(s)
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, India
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10
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Rabeh K, Oubohssaine M, Hnini M. TOR in plants: Multidimensional regulators of plant growth and signaling pathways. JOURNAL OF PLANT PHYSIOLOGY 2024; 294:154186. [PMID: 38330538 DOI: 10.1016/j.jplph.2024.154186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/10/2024]
Abstract
Target Of Rapamycin (TOR) represents a ubiquitous kinase complex that has emerged as a central regulator of cell growth and metabolism in nearly all eukaryotic organisms. TOR is an evolutionarily conserved protein kinase, functioning as a central signaling hub that integrates diverse internal and external cues to regulate a multitude of biological processes. These processes collectively exert significant influence on plant growth, development, nutrient assimilation, photosynthesis, fruit ripening, and interactions with microorganisms. Within the plant domain, the TOR complex comprises three integral components: TOR, RAPTOR, and LST8. This comprehensive review provides insights into various facets of the TOR protein, encompassing its origin, structure, function, and the regulatory and signaling pathways operative in photosynthetic organisms. Additionally, we explore future perspectives related to this pivotal protein kinase.
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Affiliation(s)
- Karim Rabeh
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco.
| | - Malika Oubohssaine
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
| | - Mohamed Hnini
- Microbiology and Molecular Biology Team, Center of Plant and Microbial Biotechnologies, Biodiversity and Environment, Faculty of Sciences, Mohammed V University, Rabat, Morocco
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11
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Brito Querido J, Sokabe M, Díaz-López I, Gordiyenko Y, Fraser CS, Ramakrishnan V. The structure of a human translation initiation complex reveals two independent roles for the helicase eIF4A. Nat Struct Mol Biol 2024; 31:455-464. [PMID: 38287194 PMCID: PMC10948362 DOI: 10.1038/s41594-023-01196-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 11/30/2023] [Indexed: 01/31/2024]
Abstract
Eukaryotic translation initiation involves recruitment of the 43S pre-initiation complex to the 5' end of mRNA by the cap-binding complex eIF4F, forming the 48S translation initiation complex (48S), which then scans along the mRNA until the start codon is recognized. We have previously shown that eIF4F binds near the mRNA exit channel of the 43S, leaving open the question of how mRNA secondary structure is removed as it enters the mRNA channel on the other side of the 40S subunit. Here we report the structure of a human 48S that shows that, in addition to the eIF4A that is part of eIF4F, there is a second eIF4A helicase bound at the mRNA entry site, which could unwind RNA secondary structures as they enter the 48S. The structure also reveals conserved interactions between eIF4F and the 43S, probaby explaining how eIF4F can promote mRNA recruitment in all eukaryotes.
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Affiliation(s)
- Jailson Brito Querido
- MRC Laboratory of Molecular Biology, Cambridge, UK
- Department of Biological Chemistry and Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Masaaki Sokabe
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of California, Davis, CA, USA
| | | | | | - Christopher S Fraser
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of California, Davis, CA, USA.
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12
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Calderan-Rodrigues MJ, Caldana C. Impact of the TOR pathway on plant growth via cell wall remodeling. JOURNAL OF PLANT PHYSIOLOGY 2024; 294:154202. [PMID: 38422631 DOI: 10.1016/j.jplph.2024.154202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 02/12/2024] [Accepted: 02/13/2024] [Indexed: 03/02/2024]
Abstract
Plant growth is intimately linked to the availability of carbon and energy status. The Target of rapamycin (TOR) pathway is a highly relevant metabolic sensor and integrator of plant-assimilated C into development and growth. The cell wall accounts for around a third of the cell biomass, and the investment of C into this structure should be finely tuned for optimal growth. The plant C status plays a significant role in controlling the rate of cell wall synthesis. TOR signaling regulates cell growth and expansion, which are fundamental processes for plant development. The availability of nutrients and energy, sensed and integrated by TOR, influences cell division and elongation, ultimately impacting the synthesis and deposition of cell wall components. The plant cell wall is crucial in environmental adaptation and stress responses. TOR senses and internalizes various environmental cues, such as nutrient availability and stresses. These environmental factors influence TOR activity, which modulates cell wall remodeling to cope with changing conditions. Plant hormones, including auxins, gibberellins, and brassinosteroids, also regulate TOR signaling and cell wall-related processes. The connection between nutrients and cell wall pathways modulated by TOR are discussed.
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Affiliation(s)
- Maria Juliana Calderan-Rodrigues
- Max-Planck Institut für Molekulare Pflanzenphysiologie, 14476, Potsdam-Golm, Germany; Universidade de São Paulo, Escola Superior de Agricultura "Luiz de Queiroz", 13418-900, Piracicaba, SP, Brazil.
| | - Camila Caldana
- Max-Planck Institut für Molekulare Pflanzenphysiologie, 14476, Potsdam-Golm, Germany
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13
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Lim MN, Lee SE, Jeon JS, Yoon IS, Hwang YS. OsbZIP38/87-mediated activation of OsHXK7 improves the viability of rice cells under hypoxic conditions. JOURNAL OF PLANT PHYSIOLOGY 2024; 293:154182. [PMID: 38277982 DOI: 10.1016/j.jplph.2024.154182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/28/2024]
Abstract
Maintenance of energy metabolism is critical for rice (Oryza sativa) tolerance under submerged cultivation. Here, OsHXK7 was the most actively induced hexokinase gene in the embryos of hypoxically germinating rice seeds. Suspension-cultured cells established from seeds of T-DNA null mutants for the OsHXK7 locus did not regrow after 3-d-hypoxic stress and showed increased susceptibility to low-oxygen stress-in terms of viability-and decreased alcoholic fermentation activities compared to those of the wild-type. The promoter element containing the TGACG-motif, a well-known target site for the basic leucine zipper (bZIP) transcription factors, was responsible for sugar regulation of the OsHXK7 promoter activity. Systematic screening of the OsbZIP genes showing the similar expression patterns to that of OsHXK7 in the transcriptomic datasets produced two bZIP genes, OsbZIP38 and 87, belonging to the S1 bZIP subfamily as the candidate for the activator for this gene expression. Gain- and loss-of-function experiments through transient expression assays have demonstrated that these two bZIP proteins are indeed involved in the induction of OsHXK7 expression under starvation or low-energy conditions. Our finding suggests that C/S1 bZIP network-mediated hypoxic deregulation of sugar-responsive genes may work in concert for the molecular adaptation of rice cells to submergence.
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Affiliation(s)
- Mi-Na Lim
- Department of Biotechnology, CHA University, Seongnam, 13488, South Korea
| | - Sung-Eun Lee
- Department of Systems Biotechnology, Konkuk University, Seoul, 143-701, South Korea
| | - Jong-Seong Jeon
- Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin, 446-701, South Korea
| | - In Sun Yoon
- Molecular Breeding Division, National Academy of Agricultural Science, Jeonju, 565-851, South Korea
| | - Yong-Sic Hwang
- Department of Systems Biotechnology, Konkuk University, Seoul, 143-701, South Korea.
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14
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Dasgupta A, Urquidi Camacho RA, Enganti R, Cho SK, Tucker LL, Torreverde JS, Abraham PE, von Arnim AG. A phosphorylation-deficient ribosomal protein eS6 is largely functional in Arabidopsis thaliana, rescuing mutant defects from global translation and gene expression to photosynthesis and growth. PLANT DIRECT 2024; 8:e566. [PMID: 38250458 PMCID: PMC10799217 DOI: 10.1002/pld3.566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/04/2023] [Accepted: 12/20/2023] [Indexed: 01/23/2024]
Abstract
The eukaryote-specific ribosomal protein of the small subunit eS6 is phosphorylated through the target of rapamycin (TOR) kinase pathway. Although this phosphorylation event responds dynamically to environmental conditions and has been studied for over 50 years, its biochemical and physiological significance remains controversial and poorly understood. Here, we report data from Arabidopsis thaliana, which indicate that plants expressing only a phospho-deficient isoform of eS6 grow essentially normally under laboratory conditions. The eS6z (RPS6A) paralog of eS6 functionally rescued a double mutant in both rps6a and rps6b genes when expressed at approximately twice the wild-type dosage. A mutant isoform of eS6z lacking the major six phosphorylatable serine and threonine residues in its carboxyl-terminal tail also rescued the lethality, rosette growth, and polyribosome loading of the double mutant. This isoform also complemented many mutant phenotypes of rps6 that were newly characterized here, including photosynthetic efficiency, and most of the gene expression defects that were measured by transcriptomics and proteomics. However, compared with plants rescued with a phospho-enabled version of eS6z, the phospho-deficient seedlings retained a mild pointed-leaf phenotype, root growth was reduced, and certain cell cycle-related mRNAs and ribosome biogenesis proteins were misexpressed. The residual defects of the phospho-deficient seedlings could be understood as an incomplete rescue of the rps6 mutant defects. There was little or no evidence for gain-of-function defects. As previously published, the phospho-deficient eS6z also rescued the rps6a and rps6b single mutants; however, phosphorylation of the eS6y (RPS6B) paralog remained lower than predicted, further underscoring that plants can tolerate phospho-deficiency of eS6 well. Our data also yield new insights into how plants cope with mutations in essential, duplicated ribosomal protein isoforms.
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Affiliation(s)
- Anwesha Dasgupta
- Department of Biochemistry & Cellular and Molecular BiologyThe University of TennesseeKnoxvilleTennesseeUSA
| | | | - Ramya Enganti
- Department of Biochemistry & Cellular and Molecular BiologyThe University of TennesseeKnoxvilleTennesseeUSA
| | - Sung Ki Cho
- Department of Biochemistry & Cellular and Molecular BiologyThe University of TennesseeKnoxvilleTennesseeUSA
| | - Lindsey L. Tucker
- Department of Biochemistry & Cellular and Molecular BiologyThe University of TennesseeKnoxvilleTennesseeUSA
| | - John S. Torreverde
- Department of Biochemistry & Cellular and Molecular BiologyThe University of TennesseeKnoxvilleTennesseeUSA
| | - Paul E. Abraham
- Graduate School of Genome Science and TechnologyThe University of TennesseeKnoxvilleTennesseeUSA
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTennesseeUSA
| | - Albrecht G. von Arnim
- Department of Biochemistry & Cellular and Molecular BiologyThe University of TennesseeKnoxvilleTennesseeUSA
- Graduate School of Genome Science and TechnologyThe University of TennesseeKnoxvilleTennesseeUSA
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15
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Zhang Z, Zhong Z, Xiong Y. Sailing in complex nutrient signaling networks: Where I am, where to go, and how to go? MOLECULAR PLANT 2023; 16:1635-1660. [PMID: 37740490 DOI: 10.1016/j.molp.2023.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/24/2023]
Abstract
To ensure survival and promote growth, sessile plants have developed intricate internal signaling networks tailored in diverse cells and organs with both shared and specialized functions that respond to various internal and external cues. A fascinating question arises: how can a plant cell or organ diagnose the spatial and temporal information it is experiencing to know "where I am," and then is able to make the accurate specific responses to decide "where to go" and "how to go," despite the absence of neuronal systems found in mammals. Drawing inspiration from recent comprehensive investigations into diverse nutrient signaling pathways in plants, this review focuses on the interactive nutrient signaling networks mediated by various nutrient sensors and transducers. We assess and illustrate examples of how cells and organs exhibit specific responses to changing spatial and temporal information within these interactive plant nutrient networks. In addition, we elucidate the underlying mechanisms by which plants employ posttranslational modification codes to integrate different upstream nutrient signals, thereby conferring response specificities to the signaling hub proteins. Furthermore, we discuss recent breakthrough studies that demonstrate the potential of modulating nutrient sensing and signaling as promising strategies to enhance crop yield, even with reduced fertilizer application.
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Affiliation(s)
- Zhenzhen Zhang
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Haixia Institute of Science and Technology, Synthetic Biology Center, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhaochen Zhong
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Haixia Institute of Science and Technology, Synthetic Biology Center, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yan Xiong
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Haixia Institute of Science and Technology, Synthetic Biology Center, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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16
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Fang JC, Liu MJ. Translation initiation at AUG and non-AUG triplets in plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 335:111822. [PMID: 37574140 DOI: 10.1016/j.plantsci.2023.111822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 07/22/2023] [Accepted: 08/07/2023] [Indexed: 08/15/2023]
Abstract
In plants and other eukaryotes, precise selection of translation initiation site (TIS) on mRNAs shapes the proteome in response to cellular events or environmental cues. The canonical translation of mRNAs initiates at a 5' proximal AUG codon in a favorable context. However, the coding and non-coding regions of plant genomes contain numerous unannotated alternative AUG and non-AUG TISs. Determining how and why these unexpected and prevalent TISs are activated in plants has emerged as an exciting research area. In this review, we focus on the selection of plant TISs and highlight studies that revealed previously unannotated TISs used in vivo via comparative genomics and genome-wide profiling of ribosome positioning and protein N-terminal ends. The biological signatures of non-AUG TIS-initiated open reading frames (ORFs) in plants are also discussed. We describe what is understood about cis-regulatory RNA elements and trans-acting eukaryotic initiation factors (eIFs) in the site selection for translation initiation by featuring the findings in plants along with supporting findings in non-plant species. The prevalent, unannotated TISs provide a hidden reservoir of ORFs that likely help reshape plant proteomes in response to developmental or environmental cues. These findings underscore the importance of understanding the mechanistic basis of TIS selection to functionally annotate plant genomes, especially for crops with large genomes.
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Affiliation(s)
- Jhen-Cheng Fang
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711, Taiwan
| | - Ming-Jung Liu
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711, Taiwan; Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan.
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17
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Guo WJ, Pommerrenig B, Neuhaus HE, Keller I. Interaction between sugar transport and plant development. JOURNAL OF PLANT PHYSIOLOGY 2023; 288:154073. [PMID: 37603910 DOI: 10.1016/j.jplph.2023.154073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/14/2023] [Accepted: 08/16/2023] [Indexed: 08/23/2023]
Abstract
Endogenous programs and constant interaction with the environment regulate the development of the plant organism and its individual organs. Sugars are necessary building blocks for plant and organ growth and at the same time act as critical integrators of the metabolic state into the developmental program. There is a growing recognition that the specific type of sugar and its subcellular or tissue distribution is sensed and translated to developmental responses. Therefore, the transport of sugars across membranes is a key process in adapting plant organ properties and overall development to the nutritional state of the plant. In this review, we discuss how plants exploit various sugar transporters to signal growth responses, for example, to control the development of sink organs such as roots or fruits. We highlight which sugar transporters are involved in root and shoot growth and branching, how intracellular sugar allocation can regulate senescence, and, for example, control fruit development. We link the important transport processes to downstream signaling cascades and elucidate the factors responsible for the integration of sugar signaling and plant hormone responses.
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Affiliation(s)
- Woei-Jiun Guo
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Benjamin Pommerrenig
- Department of Plant Physiology, University of Kaiserslautern, Erwin Schrödinger Str., 67663, Kaiserslautern, Germany
| | - H Ekkehard Neuhaus
- Department of Plant Physiology, University of Kaiserslautern, Erwin Schrödinger Str., 67663, Kaiserslautern, Germany
| | - Isabel Keller
- Department of Plant Physiology, University of Kaiserslautern, Erwin Schrödinger Str., 67663, Kaiserslautern, Germany.
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18
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Dong Y, Srour O, Lukhovitskaya N, Makarian J, Baumberger N, Galzitskaya O, Elser D, Schepetilnikov M, Ryabova LA. Functional analogs of mammalian 4E-BPs reveal a role for TOR in global plant translation. Cell Rep 2023; 42:112892. [PMID: 37516965 DOI: 10.1016/j.celrep.2023.112892] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 05/22/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
Mammalian/mechanistic target of rapamycin (mTOR) regulates global protein synthesis through inactivation of eIF4E-binding proteins (m4E-BPs) in response to nutrient and energy availability. Until now, 4E-BPs have been considered as metazoan inventions, and how target of rapamycin (TOR) controls cap-dependent translation initiation in plants remains obscure. Here, we present short unstructured 4E-BP-like Arabidopsis proteins (4EBP1/4EBP2) that are non-homologous to m4E-BPs except for the eIF4E-binding motif and TOR phosphorylation sites. Unphosphorylated 4EBPs exhibit strong affinity toward eIF4Es and can inhibit formation of the cap-binding complex. Upon TOR activation, 4EBPs are phosphorylated, probably when bound directly to TOR, and likely relocated to ribosomes. 4EBPs can suppress a distinct set of mRNAs; 4EBP2 predominantly inhibits translation of core cell-cycle regulators CycB1;1 and CycD1;1, whereas 4EBP1 interferes with chlorophyll biosynthesis. Accordingly, 4EBP2 overexpression halts early seedling development, which is overcome by induction of Glc/Suc-TOR signaling. Thus, TOR regulates cap-dependent translation initiation by inactivating atypical 4EBPs in plants.
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Affiliation(s)
- Yihan Dong
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Ola Srour
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Nina Lukhovitskaya
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Joelle Makarian
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Nicolas Baumberger
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Oxana Galzitskaya
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - David Elser
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Mikhail Schepetilnikov
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
| | - Lyubov A Ryabova
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
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19
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Xiong F, Tian J, Wei Z, Deng K, Li Y, Zhang Y. Suppression of the target of rapamycin kinase accelerates tomato fruit ripening through reprogramming the transcription profile and promoting ethylene biosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:2603-2619. [PMID: 36786543 DOI: 10.1093/jxb/erad056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 02/11/2023] [Indexed: 06/06/2023]
Abstract
Tomato fruit ripening is a unique process of nutritional and energy metabolism. Target of rapamycin (TOR), a conserved serine/threonine protein kinase in eukaryotes, controls cell growth and metabolism by integrating nutrient, energy, and hormone signals. However, it remains unclear whether TOR participates in the modulation of tomato fruit ripening. Here, we showed that the manipulation of SlTOR by chemical or genetic methods greatly alters the process of tomato fruit maturation. Expression pattern analysis revealed that the transcripts of SlTOR declined as fruit ripening progressed. Moreover, suppression of SlTOR by TOR inhibitor AZD8055 or knock down of its transcripts by inducible RNA interference, accelerated fruit ripening, and led to overall effects on fruit maturity, including changes in colour and metabolism, fruit softening, and expression of ripening-related genes. Genome-wide transcription analysis indicated that silencing SlTOR reprogrammed the transcript profile associated with ripening, including cell wall and phytohormone pathways, elevated the expression of ethylene biosynthetic genes, and further promoted ethylene production. In contrast, the ethylene action inhibitor 1-MCP efficiently blocked fruit maturation, even following SlTOR inhibition. These results suggest that accelerated fruit ripening caused by SlTOR inhibition depends on ethylene, and that SlTOR may function as a regulator in ethylene metabolism.
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Affiliation(s)
- Fangjie Xiong
- Biotechnology Research Center, Southwest University, Chongqing 400716, China
- School of Life Sciences, Chongqing University, Chongqing 401331, China
| | - Jianwei Tian
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Zhenzhen Wei
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Kexuan Deng
- School of Life Sciences, Chongqing University, Chongqing 401331, China
- College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, China
| | - Yan Li
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Yanjie Zhang
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China
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20
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Chen Q, Qu M, Chen Q, Meng X, Fan H. Phosphoproteomics analysis of the effect of target of rapamycin kinase inhibition on Cucumis sativus in response to Podosphaera xanthii. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 197:107641. [PMID: 36940522 DOI: 10.1016/j.plaphy.2023.107641] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 03/12/2023] [Accepted: 03/13/2023] [Indexed: 06/18/2023]
Abstract
Target of rapamycin (TOR) kinase is a conserved sensor of cell growth in yeasts, plants, and mammals. Despite the extensive research on the TOR complex in various biological processes, large-scale phosphoproteomics analysis of TOR phosphorylation events upon environmental stress are scarce. Powdery mildew caused by Podosphaera xanthii poses a major threat to the quality and yield of cucumber (Cucumis sativus L.). Previous studies concluded that TOR participated in abiotic and biotic stress responses. Hence, studying the underlying mechanism of TOR-P. xanthii infection is particularly important. In this study, we performed a quantitative phosphoproteomics studies of Cucumis against P. xanthii attack under AZD-8055 (TOR inhibitor) pretreatment. A total of 3384 phosphopeptides were identified from the 1699 phosphoproteins. The Motif-X analysis showed high sensitivity and specificity of serine sites under AZD-8055-treatment or P. xanthii stress, and TOR exhibited a unique preference for proline at +1 position and glycine at -1 position to enhance the phosphorylation response to P. xanthii. The functional analysis suggested that the unique responses were attributed to proteins related to plant hormone signaling, mitogen-activated protein kinase cascade signaling, phosphatidylinositol signaling system, and circadian rhythm; and calcium signaling- and defense response-related proteins. Our results provided rich resources for understanding the molecular mechanism of how the TOR kinase controlled plant growth and stress adaptation.
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Affiliation(s)
- Qiumin Chen
- College of Horticulture, Shenyang Agricultural University, Shenyang, 110866, China
| | - Mengqi Qu
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China
| | - Qinglei Chen
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China
| | - Xiangnan Meng
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China; Key Laboratory of Protected Horticulture of Ministry of Education, Shenyang Agricultural University, Shenyang, 110866, China; Key Laboratory of Biology and Genetic Improvement of Fruit Vegetables of Shenyang, Shenyang Agricultural University, Shenyang, 110866, China.
| | - Haiyan Fan
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China; Key Laboratory of Protected Horticulture of Ministry of Education, Shenyang Agricultural University, Shenyang, 110866, China; Key Laboratory of Biology and Genetic Improvement of Fruit Vegetables of Shenyang, Shenyang Agricultural University, Shenyang, 110866, China.
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21
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Corydon TJ, Schulz H, Richter P, Strauch SM, Böhmer M, Ricciardi DA, Wehland M, Krüger M, Erzinger GS, Lebert M, Infanger M, Wise PM, Grimm D. Current Knowledge about the Impact of Microgravity on Gene Regulation. Cells 2023; 12:cells12071043. [PMID: 37048115 PMCID: PMC10093652 DOI: 10.3390/cells12071043] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/24/2023] [Accepted: 03/25/2023] [Indexed: 03/31/2023] Open
Abstract
Microgravity (µg) has a massive impact on the health of space explorers. Microgravity changes the proliferation, differentiation, and growth of cells. As crewed spaceflights into deep space are being planned along with the commercialization of space travelling, researchers have focused on gene regulation in cells and organisms exposed to real (r-) and simulated (s-) µg. In particular, cancer and metastasis research benefits from the findings obtained under µg conditions. Gene regulation is a key factor in a cell or an organism’s ability to sustain life and respond to environmental changes. It is a universal process to control the amount, location, and timing in which genes are expressed. In this review, we provide an overview of µg-induced changes in the numerous mechanisms involved in gene regulation, including regulatory proteins, microRNAs, and the chemical modification of DNA. In particular, we discuss the current knowledge about the impact of microgravity on gene regulation in different types of bacteria, protists, fungi, animals, humans, and cells with a focus on the brain, eye, endothelium, immune system, cartilage, muscle, bone, and various cancers as well as recent findings in plants. Importantly, the obtained data clearly imply that µg experiments can support translational medicine on Earth.
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Affiliation(s)
- Thomas J. Corydon
- Department of Biomedicine, Aarhus University, Hoegh Guldbergs Gade 10, 8000 Aarhus, Denmark
- Department of Ophthalmology, Aarhus University Hospital, Palle Juul-Jensens Blvd. 99, 8200 Aarhus, Denmark
- Correspondence: ; Tel.: +45-28-992-179
| | - Herbert Schulz
- Department of Microgravity and Translational Regenerative Medicine, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Clinic for Plastic, Aesthetic and Hand Surgery, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Leipziger Straße 44, 39120 Magdeburg, Germany
- Research Group ‘Magdeburger Arbeitsgemeinschaft für Forschung unter Raumfahrt-und Schwerelosigkeitsbedingungen’ (MARS), Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
| | - Peter Richter
- Gravitational Biology Group, Department of Biology, Friedrich-Alexander University, 91058 Erlangen, Germany
| | - Sebastian M. Strauch
- Postgraduate Program in Health and Environment, University of Joinville Region, Joinville 89219-710, SC, Brazil
| | - Maik Böhmer
- Institute for Molecular Biosciences, Johann Wolfgang Goethe Universität, 60438 Frankfurt am Main, Germany
| | - Dario A. Ricciardi
- Institute for Molecular Biosciences, Johann Wolfgang Goethe Universität, 60438 Frankfurt am Main, Germany
| | - Markus Wehland
- Department of Microgravity and Translational Regenerative Medicine, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Clinic for Plastic, Aesthetic and Hand Surgery, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Leipziger Straße 44, 39120 Magdeburg, Germany
- Research Group ‘Magdeburger Arbeitsgemeinschaft für Forschung unter Raumfahrt-und Schwerelosigkeitsbedingungen’ (MARS), Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
| | - Marcus Krüger
- Department of Microgravity and Translational Regenerative Medicine, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Research Group ‘Magdeburger Arbeitsgemeinschaft für Forschung unter Raumfahrt-und Schwerelosigkeitsbedingungen’ (MARS), Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
| | - Gilmar S. Erzinger
- Postgraduate Program in Health and Environment, University of Joinville Region, Joinville 89219-710, SC, Brazil
| | - Michael Lebert
- Gravitational Biology Group, Department of Biology, Friedrich-Alexander University, 91058 Erlangen, Germany
| | - Manfred Infanger
- Department of Microgravity and Translational Regenerative Medicine, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Clinic for Plastic, Aesthetic and Hand Surgery, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Leipziger Straße 44, 39120 Magdeburg, Germany
- Research Group ‘Magdeburger Arbeitsgemeinschaft für Forschung unter Raumfahrt-und Schwerelosigkeitsbedingungen’ (MARS), Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
| | - Petra M. Wise
- Department of Microgravity and Translational Regenerative Medicine, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Research Group ‘Magdeburger Arbeitsgemeinschaft für Forschung unter Raumfahrt-und Schwerelosigkeitsbedingungen’ (MARS), Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- The Saban Research Institute, Children’s Hospital Los Angeles, University of Southern California, 4650 Sunset Blvd, Los Angeles, CA 90027, USA
| | - Daniela Grimm
- Department of Biomedicine, Aarhus University, Hoegh Guldbergs Gade 10, 8000 Aarhus, Denmark
- Department of Microgravity and Translational Regenerative Medicine, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
- Clinic for Plastic, Aesthetic and Hand Surgery, Medical Faculty, University Hospital Magdeburg, Otto von Guericke University, Leipziger Straße 44, 39120 Magdeburg, Germany
- Research Group ‘Magdeburger Arbeitsgemeinschaft für Forschung unter Raumfahrt-und Schwerelosigkeitsbedingungen’ (MARS), Otto von Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
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22
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Ahmed MR, Du Z. Molecular Interaction of Nonsense-Mediated mRNA Decay with Viruses. Viruses 2023; 15:v15040816. [PMID: 37112798 PMCID: PMC10141005 DOI: 10.3390/v15040816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/14/2023] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
The virus–host interaction is dynamic and evolutionary. Viruses have to fight with hosts to establish successful infection. Eukaryotic hosts are equipped with multiple defenses against incoming viruses. One of the host antiviral defenses is the nonsense-mediated mRNA decay (NMD), an evolutionarily conserved mechanism for RNA quality control in eukaryotic cells. NMD ensures the accuracy of mRNA translation by removing the abnormal mRNAs harboring pre-matured stop codons. Many RNA viruses have a genome that contains internal stop codon(s) (iTC). Akin to the premature termination codon in aberrant RNA transcripts, the presence of iTC would activate NMD to degrade iTC-containing viral genomes. A couple of viruses have been reported to be sensitive to the NMD-mediated antiviral defense, while some viruses have evolved with specific cis-acting RNA features or trans-acting viral proteins to overcome or escape from NMD. Recently, increasing light has been shed on the NMD–virus interaction. This review summarizes the current scenario of NMD-mediated viral RNA degradation and classifies various molecular means by which viruses compromise the NMD-mediated antiviral defense for better infection in their hosts.
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Affiliation(s)
| | - Zhiyou Du
- Correspondence: ; Tel.: +86-571-86843195
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23
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Wang L, Xu F, Yu F. Two environmental signal-driven RNA metabolic processes: Alternative splicing and translation. PLANT, CELL & ENVIRONMENT 2023; 46:718-732. [PMID: 36609800 DOI: 10.1111/pce.14537] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/29/2022] [Accepted: 01/06/2023] [Indexed: 06/17/2023]
Abstract
Plants live in fixed locations and have evolved adaptation mechanisms that integrate multiple responses to various environmental signals. Among the different components of these response pathways, receptors/sensors represent nodes that recognise environmental signals. Additionally, RNA metabolism plays an essential role in the regulation of gene expression and protein synthesis. With the development of RNA biotechnology, recent advances have been made in determining the roles of RNA metabolism in response to different environmental signals-especially the roles of alternative splicing and translation. In this review, we discuss recent progress in research on how the environmental adaptation mechanisms in plants are affected at the posttranscriptional level. These findings improve our understanding of the mechanism through which plants adapt to environmental changes by regulating the posttranscriptional level and are conducive for breeding stress-tolerant plants to cope with dynamic and rapidly changing environments.
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Affiliation(s)
- Long Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha, China
| | - Fan Xu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha, China
| | - Feng Yu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha, China
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
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24
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Son S, Park SR. Plant translational reprogramming for stress resilience. FRONTIERS IN PLANT SCIENCE 2023; 14:1151587. [PMID: 36909402 PMCID: PMC9998923 DOI: 10.3389/fpls.2023.1151587] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
Organisms regulate gene expression to produce essential proteins for numerous biological processes, from growth and development to stress responses. Transcription and translation are the major processes of gene expression. Plants evolved various transcription factors and transcriptome reprogramming mechanisms to dramatically modulate transcription in response to environmental cues. However, even the genome-wide modulation of a gene's transcripts will not have a meaningful effect if the transcripts are not properly biosynthesized into proteins. Therefore, protein translation must also be carefully controlled. Biotic and abiotic stresses threaten global crop production, and these stresses are seriously deteriorating due to climate change. Several studies have demonstrated improved plant resistance to various stresses through modulation of protein translation regulation, which requires a deep understanding of translational control in response to environmental stresses. Here, we highlight the translation mechanisms modulated by biotic, hypoxia, heat, and drought stresses, which are becoming more serious due to climate change. This review provides a strategy to improve stress tolerance in crops by modulating translational regulation.
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25
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Dong Y, Ryabova LA. Do plants drive translation reinitiation to dodge nonsense-mediated decay? JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:7-11. [PMID: 36563104 PMCID: PMC9786829 DOI: 10.1093/jxb/erac444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 11/08/2022] [Indexed: 06/17/2023]
Abstract
This article comments on: Cymerman MA, Saul H, Farhi R, Vexler K, Gottlieb D, Berezin I, Shaul O. 2023. Plant transcripts with long or structured upstream open reading frames in the NDL2 5ʹ UTR can escape nonsense-mediated mRNA decay in a reinitiation-independent manner. Journal of Experimental Botany 74, 91–103.
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Affiliation(s)
- Yihan Dong
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
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26
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Bakshi A, Moin M, Gayatri MB, Reddy ABM, Datla R, Madhav MS, Kirti PB. Involvement of Target of Rapamycin (TOR) Signaling in the Regulation of Crosstalk between Ribosomal Protein Small Subunit 6 Kinase-1 (RPS6K-1) and Ribosomal Proteins. PLANTS (BASEL, SWITZERLAND) 2023; 12:176. [PMID: 36616305 PMCID: PMC9824793 DOI: 10.3390/plants12010176] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
The target of rapamycin (TOR) protein phosphorylates its downstream effector p70kDa ribosomal protein S6 kinases (S6K1) for ribosome biogenesis and translation initiation in eukaryotes. However, the molecular mechanism of TOR-S6K1-ribosomal protein (RP) signaling is not well understood in plants. In the present study, we report the transcriptional upregulation of ribosomal protein large and small subunit (RPL and RPS) genes in the previously established TOR overexpressing transgenic lines of rice (in Oryza sativa ssp. indica, variety BPT-5204, TR-2.24 and TR-15.1) and of Arabidopsis thaliana (in Col 0 ecotype, ATR-1.4.27 and ATR-3.7.32). The mRNA levels of RP genes from this study were compared with those previously available in transcriptomic datasets on the expression of RPs in relation to TOR inhibitor and in the TOR-RNAi lines of Arabidopsis thaliana. We further analyzed TOR activity, i.e., S6K1 phosphorylation in SALK lines of Arabidopsis with mutation in rpl6, rpl18, rpl23, rpl24 and rps28C, where the rpl18 mutant showed inactivation of S6K1 phosphorylation. We also predicted similar putative Ser/Thr phosphorylation sites for ribosomal S6 kinases (RSKs) in the RPs of Oryza sativa ssp. indica and Arabidopsis thaliana. The findings of this study indicate that the TOR pathway is possibly interlinked in a cyclic manner via the phosphorylation of S6K1 as a modulatory step for the regulation of RP function to switch 'on'/'off' the translational regulation for balanced plant growth.
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Affiliation(s)
- Achala Bakshi
- Indian Institute of Rice Research, Rajendranagar, Hyderabad 500030, Telangana, India
- Global Institute for Food Security, Saskatoon, SK S7N 0W9, Canada
| | - Mazahar Moin
- Indian Institute of Rice Research, Rajendranagar, Hyderabad 500030, Telangana, India
- Agri Biotech Foundation, PJTS Agricultural University Campus, Rajendranagar, Hyderabad 500030, Telangana, India
| | - Meher B. Gayatri
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Aramati B. M. Reddy
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Raju Datla
- Global Institute for Food Security, Saskatoon, SK S7N 0W9, Canada
| | - Maganti S. Madhav
- Indian Institute of Rice Research, Rajendranagar, Hyderabad 500030, Telangana, India
- Central Tobacco Research Institute, Rajahmundry 533105, Andhra Pradesh, India
| | - Pulugurtha B. Kirti
- Agri Biotech Foundation, PJTS Agricultural University Campus, Rajendranagar, Hyderabad 500030, Telangana, India
- Department of Plant Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India
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27
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Jamsheer K M, Awasthi P, Laxmi A. The social network of target of rapamycin complex 1 in plants. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:7026-7040. [PMID: 35781571 DOI: 10.1093/jxb/erac278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Target of rapamycin complex 1 (TORC1) is a highly conserved serine-threonine protein kinase crucial for coordinating growth according to nutrient availability in eukaryotes. It works as a central integrator of multiple nutrient inputs such as sugar, nitrogen, and phosphate and promotes growth and biomass accumulation in response to nutrient sufficiency. Studies, especially in the past decade, have identified the central role of TORC1 in regulating growth through interaction with hormones, photoreceptors, and stress signaling machinery in plants. In this review, we comprehensively analyse the interactome and phosphoproteome of the Arabidopsis TORC1 signaling network. Our analysis highlights the role of TORC1 as a central hub kinase communicating with the transcriptional and translational apparatus, ribosomes, chaperones, protein kinases, metabolic enzymes, and autophagy and stress response machinery to orchestrate growth in response to nutrient signals. This analysis also suggests that along with the conserved downstream components shared with other eukaryotic lineages, plant TORC1 signaling underwent several evolutionary innovations and co-opted many lineage-specific components during. Based on the protein-protein interaction and phosphoproteome data, we also discuss several uncharacterized and unexplored components of the TORC1 signaling network, highlighting potential links for future studies.
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Affiliation(s)
- Muhammed Jamsheer K
- Amity Institute of Genome Engineering, Amity University Uttar Pradesh, Noida 201313, India
| | - Prakhar Awasthi
- National Institute of Plant Genome Research, New Delhi 110067, India
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, New Delhi 110067, India
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28
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Scarpin MR, Simmons CH, Brunkard JO. Translating across kingdoms: target of rapamycin promotes protein synthesis through conserved and divergent pathways in plants. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:7016-7025. [PMID: 35770874 PMCID: PMC9664230 DOI: 10.1093/jxb/erac267] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 06/16/2022] [Indexed: 06/15/2023]
Abstract
mRNA translation is the growth rate-limiting step in genome expression. Target of rapamycin (TOR) evolved a central regulatory role in eukaryotes as a signaling hub that monitors nutrient availability to maintain homeostasis and promote growth, largely by increasing the rate of translation initiation and protein synthesis. The dynamic pathways engaged by TOR to regulate translation remain debated even in well-studied yeast and mammalian models, however, despite decades of intense investigation. Recent studies have firmly established that TOR also regulates mRNA translation in plants through conserved mechanisms, such as the TOR-LARP1-5'TOP signaling axis, and through pathways specific to plants. Here, we review recent advances in our understanding of the regulation of mRNA translation in plants by TOR.
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Affiliation(s)
- M Regina Scarpin
- Laboratory of Genetics, University of Wisconsin, Madison, WI, USA
- Department of Plant and Microbial Biology, University of California, Berkeley,CA, USA
- Plant Gene Expression Center, USDA Agricultural Research Service, Albany, CA, USA
| | - Carl H Simmons
- Laboratory of Genetics, University of Wisconsin, Madison, WI, USA
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29
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Øvrebø JI, Ma Y, Edgar BA. Cell growth and the cell cycle: New insights about persistent questions. Bioessays 2022; 44:e2200150. [PMID: 36222263 DOI: 10.1002/bies.202200150] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 11/08/2022]
Abstract
Before a cell divides into two daughter cells, it typically doubles not only its DNA, but also its mass. Numerous studies in cells ranging from yeast to mammals have shown that cellular growth, stimulated by nutrients and/or growth factor signaling, is a prerequisite for cell cycle progression in most types of cells. The textbook view of growth-regulated cell cycles is that growth signaling activates the transcription of G1 Cyclin genes to induce cell proliferation, and also stimulates anabolic metabolism and cell growth in parallel. However, genetic knockout tests in model organisms indicate that this is not the whole story, and new studies show that additional, "smarter" mechanisms help to coordinate the cell cycle with growth itself. Here we summarize recent advances in this field, and discuss current models in which growth signaling regulates cell proliferation by targeting core cell cycle regulators via non-transcriptional mechanisms.
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Affiliation(s)
- Jan Inge Øvrebø
- Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, Norway
| | - Yiqin Ma
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, USA
| | - Bruce A Edgar
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, USA
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30
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Caló G, De Marco MA, Salerno GL, Martínez-Noël GMA. TOR signaling in the green picoalga Ostreococcus tauri. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 323:111390. [PMID: 35868347 DOI: 10.1016/j.plantsci.2022.111390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/29/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Target of rapamycin (TOR) is a master regulator that controls growth and metabolism by integrating external and internal signals. Although there was a great progress in the study of TOR in plants and in the model alga Chlamydomonas, scarce data are available in other green algae. Thus, in this work we studied TOR signaling in Ostreococcus tauri, the smallest free-living eukaryote described to date. This picoalga is particularly important because it has a key site at the base of the green lineage and is part of the marine phytoplankton, contributing to global photosynthesis. We investigated OtTOR complex in silico and experimentally, by using first- and second-generation TOR inhibitors, such as rapamycin and PP242. We analyzed the effect of TOR down-regulation on cell growth and on the accumulation of carbon reserves. The results showed that O. tauri responds to TOR inhibitors more similarly to plants than to Chlamydomonas, being PP242 a valuable tool to study this pathway. Besides, Ottor expression analysis revealed that the kinase is dynamically regulated under nutritional stress. Our data indicate that TOR signaling is conserved in O. tauri and we propose this alga as a good and simple model for studying TOR kinase and its regulation.
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Affiliation(s)
- Gonzalo Caló
- INBIOTEC, Vieytes, 3103, 7600 Mar del Plata, Argentina; FIBA, Vieytes 3103, 7600 Mar del Plata, Argentina
| | - María Agustina De Marco
- INBIOTEC, Vieytes, 3103, 7600 Mar del Plata, Argentina; FIBA, Vieytes 3103, 7600 Mar del Plata, Argentina
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31
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Dong Y, Aref R, Forieri I, Schiel D, Leemhuis W, Meyer C, Hell R, Wirtz M. The plant TOR kinase tunes autophagy and meristem activity for nutrient stress-induced developmental plasticity. THE PLANT CELL 2022; 34:3814-3829. [PMID: 35792878 PMCID: PMC9516127 DOI: 10.1093/plcell/koac201] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/29/2022] [Indexed: 05/26/2023]
Abstract
Plants, unlike animals, respond to environmental challenges with comprehensive developmental transitions that allow them to cope with these stresses. Here we discovered that antagonistic activation of the Target of Rapamycin (TOR) kinase in Arabidopsis thaliana roots and shoots is essential for the nutrient deprivation-induced increase in the root-to-shoot ratio to improve foraging for mineral ions. We demonstrate that sulfate limitation-induced downregulation of TOR in shoots activates autophagy, resulting in enhanced carbon allocation to the root. The allocation of carbon to the roots is facilitated by the specific upregulation of the sucrose-transporter genes SWEET11/12 in shoots. SWEET11/12 activation is indispensable for enabling sucrose to act as a carbon source for growth and as a signal for tuning root apical meristem activity via glucose-TOR signaling. The sugar-stimulated TOR activity in the root suppresses autophagy and maintains root apical meristem activity to support root growth to enhance mining for new sulfate resources in the soil. We provide direct evidence that the organ-specific regulation of autophagy is essential for the increased root-to-shoot ratio in response to sulfur limitation. These findings uncover how sulfur limitation controls the central sensor kinase TOR to enable nutrient recycling for stress-induced morphological adaptation of the plant body.
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Affiliation(s)
- Yihan Dong
- Centre for Organismal Studies (COS), University of Heidelberg, 69120 Heidelberg, Germany
| | - Rasha Aref
- Centre for Organismal Studies (COS), University of Heidelberg, 69120 Heidelberg, Germany
- Department of Genetics, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Ilaria Forieri
- Centre for Organismal Studies (COS), University of Heidelberg, 69120 Heidelberg, Germany
| | - David Schiel
- Centre for Organismal Studies (COS), University of Heidelberg, 69120 Heidelberg, Germany
| | - Wiebke Leemhuis
- Centre for Organismal Studies (COS), University of Heidelberg, 69120 Heidelberg, Germany
| | - Christian Meyer
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, 78000 Versailles, France
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32
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Early signaling events in the heat stress response of Pyropia haitanensis revealed by phosphoproteomic and lipidomic analyses. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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33
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Ciacka K, Tyminski M, Wal A, Gniazdowska A, Krasuska U. Nitric oxide-an antidote to seed aging modifies meta-tyrosine content and expression of aging-linked genes in apple embryos. FRONTIERS IN PLANT SCIENCE 2022; 13:929245. [PMID: 36110361 PMCID: PMC9468924 DOI: 10.3389/fpls.2022.929245] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
Short-term (3 h) treatment of embryos isolated from accelerated aged apple seeds (Malus domestica Borkh.) with nitric oxide (NO) partially reduced the effects of aging. The study aimed to investigate the impact of the short-term NO treatment of embryos isolated from apple seeds subjected to accelerated aging on the expression of genes potentially linked to the regulation of seed aging. Apple seeds were artificially aged for 7, 14, or 21 days. Then, the embryos were isolated from the seeds, treated with NO, and cultured for 48 h. Progression of seed aging was associated with the decreased transcript levels of most of the analyzed genes (Lea1, Lea2a, Lea4, Hsp70b, Hsp20a, Hsp20b, ClpB1, ClpB4, Cpn60a, Cpn60b, Raptor, and Saur). The role of NO in the mitigation of seed aging depended on the duration of the aging. After 7 and 14 days of seed aging, a decreased expression of genes potentially associated with the promotion of aging (Tor, Raptor, Saur) was noted. NO-dependent regulation of seed aging was associated with the stimulation of the expression of genes encoding chaperones and proteins involved in the repair of damaged proteins. After NO application, the greatest upregulation of ClpB, Pimt was noted in the embryos isolated from seeds subjected to 7-day long accelerated aging, Hsp70b, Hsp70c, and Cpn in the embryos of seeds aged for 14 days, and Lea2a in the embryos of seeds after 21 days of aging. We also demonstrated the increased meta-tyrosine concentration depending or in respect the progression of artificial aging, and the NO-induced increased phenylalanine content in seeds artificially aged for 21 days. In the NO-treated embryos of seeds aged for 7 and 21 days, the level of tyrosine was almost doubled compared to the aged tissue. Our data confirmed the usage of meta-tyrosine as a marker of seed aging and indicated that the increased meta-tyrosine/tyrosine ratio could be related to the loss of seed viability.
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34
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Marash I, Leibman‐Markus M, Gupta R, Avni A, Bar M. TOR inhibition primes immunity and pathogen resistance in tomato in a salicylic acid-dependent manner. MOLECULAR PLANT PATHOLOGY 2022; 23:1035-1047. [PMID: 35441436 PMCID: PMC9190978 DOI: 10.1111/mpp.13207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 02/08/2022] [Accepted: 02/18/2022] [Indexed: 06/14/2023]
Abstract
All organisms need to sense and process information about the availability of nutrients, energy status, and environmental cues to determine the best time for growth and development. The conserved target of rapamycin (TOR) protein kinase has a central role in sensing and perceiving nutritional information. TOR connects environmental information about nutrient availability to developmental and metabolic processes to maintain cellular homeostasis. Under favourable energy conditions, TOR is activated and promotes anabolic processes such as cell division, while suppressing catabolic processes. Conversely, when nutrients are limited or environmental stresses are present, TOR is inactivated, and catabolic processes are promoted. Given the central role of TOR in regulating metabolism, several previous works have examined whether TOR is wired to plant defence. To date, the mechanisms by which TOR influences plant defence are not entirely clear. Here, we addressed this question by testing the effect of inhibiting TOR on immunity and pathogen resistance in tomato. Examining which hormonal defence pathways are influenced by TOR, we show that tomato immune responses and disease resistance to several pathogens increase on TOR inhibition, and that TOR inhibition-mediated resistance probably requires a functional salicylic acid, but not jasmonic acid, pathway. Our results support the notion that TOR is a master regulator of the development-defence switch in plants.
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Affiliation(s)
- Iftah Marash
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
- School of Plant Science and Food SecurityTel‐Aviv UniversityTel‐AvivIsrael
| | - Meirav Leibman‐Markus
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| | - Rupali Gupta
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
| | - Adi Avni
- School of Plant Science and Food SecurityTel‐Aviv UniversityTel‐AvivIsrael
| | - Maya Bar
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationVolcani InstituteBet DaganIsrael
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35
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Mechanisms Regulating Energy Homeostasis in Plant Cells and Their Potential to Inspire Electrical Microgrids Models. Biomimetics (Basel) 2022; 7:biomimetics7020083. [PMID: 35735599 PMCID: PMC9221007 DOI: 10.3390/biomimetics7020083] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/09/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022] Open
Abstract
In this paper, the main features of systems that are required to flexibly modulate energy states of plant cells in response to environmental fluctuations are surveyed and summarized. Plant cells possess multiple sources (chloroplasts and mitochondria) to produce energy that is consumed to drive many processes, as well as mechanisms that adequately provide energy to the processes with high priority depending on the conditions. Such energy-providing systems are tightly linked to sensors that monitor the status of the environment and inside the cell. In addition, plants possess the ability to efficiently store and transport energy both at the cell level and at a higher level. Furthermore, these systems can finely tune the various mechanisms of energy homeostasis in plant cells in response to the changes in environment, also assuring the plant survival under adverse environmental conditions. Electrical power systems are prone to the effects of environmental changes as well; furthermore, they are required to be increasingly resilient to the threats of extreme natural events caused, for example, by climate changes, outages, and/or external deliberate attacks. Starting from this consideration, similarities between energy-related processes in plant cells and electrical power grids are identified, and the potential of mechanisms regulating energy homeostasis in plant cells to inspire the definition of new models of flexible and resilient electrical power grids, particularly microgrids, is delineated. The main contribution of this review is surveying energy regulatory mechanisms in detail as a reference and helping readers to find useful information for their work in this research field.
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36
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McCready K, Spencer V, Jácome-Blásquez F, Burnett J, Viveros Sánchez IM, Riches Z, Kim M. TARGET OF RAPAMYCIN is essential for asexual vegetative reproduction in Kalanchoë. PLANT PHYSIOLOGY 2022; 189:248-263. [PMID: 34935983 PMCID: PMC9070829 DOI: 10.1093/plphys/kiab589] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 11/19/2021] [Indexed: 06/14/2023]
Abstract
The unique mechanism by which leaf margin cells regain potency and then form a plantlet in Kalanchoë spp. remains elusive but involves organogenesis and embryogenesis in response to age, day length, nutrient availability, and drought stress. In light of this, we investigated whether TARGET OF RAPAMYCIN (TOR), a conserved protein kinase in eukaryotes that controls cell growth and metabolism in response to nutrient and energy availability, may regulate plantlet formation. Kalanchoë daigremontiana TOR (KdTOR) was expressed in the leaf margin at the site of plantlet initiation, in the early plantlet cotyledons, and in the root tip of the developed plantlet. Both chemical and genetic inhibition of TOR Kinase activity in Kalanchoë daigremontiana leaves disrupted plantlet formation. Furthermore, downregulation of KdTOR in transgenic plants led to wide-ranging transcriptional changes, including decreased K. daigremontiana SHOOTMERISTEMLESS and K. daigremontiana LEAFYCOTYLEDON1 expression, whereas auxin treatments induced KdTOR expression in the plantlet roots. These results suggest that the KdTOR pathway controls plantlet development in cooperation with auxin, organogenesis, and embryogenesis pathways. The ancient and highly conserved TOR Kinase therefore controls diverse and unique developmental pathways, such as asexual reproduction within the land plant lineage.
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Affiliation(s)
| | | | - Francisco Jácome-Blásquez
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT, UK
| | - Jamie Burnett
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT, UK
| | | | - Zara Riches
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, M13 9PT, UK
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37
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Linster E, Forero Ruiz FL, Miklankova P, Ruppert T, Mueller J, Armbruster L, Gong X, Serino G, Mann M, Hell R, Wirtz M. Cotranslational N-degron masking by acetylation promotes proteome stability in plants. Nat Commun 2022; 13:810. [PMID: 35145090 PMCID: PMC8831508 DOI: 10.1038/s41467-022-28414-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 01/14/2022] [Indexed: 11/23/2022] Open
Abstract
N-terminal protein acetylation (NTA) is a prevalent protein modification essential for viability in animals and plants. The dominant executor of NTA is the ribosome tethered Nα-acetyltransferase A (NatA) complex. However, the impact of NatA on protein fate is still enigmatic. Here, we demonstrate that depletion of NatA activity leads to a 4-fold increase in global protein turnover via the ubiquitin-proteasome system in Arabidopsis. Surprisingly, a concomitant increase in translation, actioned via enhanced Target-of-Rapamycin activity, is also observed, implying that defective NTA triggers feedback mechanisms to maintain steady-state protein abundance. Quantitative analysis of the proteome, the translatome, and the ubiquitome reveals that NatA substrates account for the bulk of this enhanced turnover. A targeted analysis of NatA substrate stability uncovers that NTA absence triggers protein destabilization via a previously undescribed and widely conserved nonAc/N-degron in plants. Hence, the imprinting of the proteome with acetylation marks is essential for coordinating proteome stability. N-terminal protein acetylation is required for plant viability. Here the authors show that reducing N-terminal acetylation by NatA leads to an increase in global protein turnover that is facilitated by absent masking of a novel N-degron
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Affiliation(s)
- Eric Linster
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Francy L Forero Ruiz
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Pavlina Miklankova
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Thomas Ruppert
- Center for Molecular Biology Heidelberg, Heidelberg University, Heidelberg, Germany
| | | | - Laura Armbruster
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Xiaodi Gong
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Giovanna Serino
- Department of Biology and Biotechnology, Sapienza Università di Roma, Rome, Italy
| | - Matthias Mann
- Max-Planck-Institute for Biochemistry, Martinsried, Germany
| | - Rüdiger Hell
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Markus Wirtz
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany.
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38
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Translational control of E2f1 regulates the Drosophila cell cycle. Proc Natl Acad Sci U S A 2022; 119:2113704119. [PMID: 35074910 PMCID: PMC8795540 DOI: 10.1073/pnas.2113704119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2021] [Indexed: 12/21/2022] Open
Abstract
E2F transcription factors are master regulators of the eukaryotic cell cycle. In Drosophila, the sole activating E2F, E2F1, is both required for and sufficient to promote G1→S progression. E2F1 activity is regulated both by binding to RB Family repressors and by posttranscriptional control of E2F1 protein levels by the EGFR and TOR signaling pathways. Here, we investigate cis-regulatory elements in the E2f1 messenger RNA (mRNA) that enable E2f1 translation to respond to these signals and promote mitotic proliferation of wing imaginal disc and intestinal stem cells. We show that small upstream open reading frames (uORFs) in the 5' untranslated region (UTR) of the E2f1 mRNA limit its translation, impacting rates of cell proliferation. E2f1 transgenes lacking these 5'UTR uORFs caused TOR-independent expression and excess cell proliferation, suggesting that TOR activity can bypass uORF-mediated translational repression. EGFR signaling also enhanced translation but through a mechanism less dependent on 5'UTR uORFs. Further, we mapped a region in the E2f1 mRNA that contains a translational enhancer, which may also be targeted by TOR signaling. This study reveals translational control mechanisms through which growth signaling regulates cell cycle progression.
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39
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Song S, Liu J, Zhang M, Gao X, Sun W, Liu P, Wang Y, Li J. Eukaryotic translation initiation factor 3 subunit B could serve as a potential prognostic predictor for breast cancer. Bioengineered 2022; 13:2762-2776. [PMID: 35040374 PMCID: PMC8974155 DOI: 10.1080/21655979.2021.2017567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The EIF3 gene family is essential in controlling translation initiation during the cell cycle. The significance of the EIF3 subunits as prognostic markers and therapeutic targets in breast cancer is not yet clear. We analyzed the expression of EIF3 subunits in breast cancer on the GEPIA and Oncomine databases and compared their expression in breast cancer and normal tissues using BRCA data downloaded from TCGA. Then we performed clinical survival analysis on the Kaplan–Meier Plotter database and clinicopathologic analysis on the bc-genexMiner v4.1 database. And EIF3B was chosen for mutation analysis via the Cancer SEA online tool. Meanwhile, we performed the immunohistochemical assay, real-time RT-PCR, and Western blotting to analyze EIF3B expression levels in breast cancer. An EIF3B knockdown and a negative control cell line were conducted for MTT assay and cell cycle analysis to assess cell growth. Specifically, the results of TCGA and online databases demonstrated that upregulated EIF3B was associated with poorer overall and advanced tumor progression. We also confirmed that EIF3B was more highly expressed in breast cancer cells and tissues than normal and correlated with a worse outcome. And knockdown of EIF3B expression inhibited the cell cycle and proliferation. Furthermore, EIF3B was highly mutated in breast cancer. Collectively, our results suggested EIF3B as a potential prognostic marker and therapeutic target for breast cancer.
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Affiliation(s)
- Shaoran Song
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Jie Liu
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Miao Zhang
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Xiaoqian Gao
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Wei Sun
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Peijun Liu
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Yaochun Wang
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
| | - Juan Li
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,The Key Laboratory for Tumor Precision Medicine of Shaanxi Province, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi China
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40
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Abstract
The target of rapamycin (TOR) kinase is a master regulator that integrates nutrient signals to promote cell growth in all eukaryotes. It is well established that amino acids and glucose are major regulators of TOR signaling in yeast and metazoan, but whether and how TOR responds to carbon availability in photosynthetic organisms is less understood. In this study, we showed that photosynthetic assimilation of CO2 by the Calvin-Benson-Bassham (CBB) cycle regulates TOR activity in the model single-celled microalga Chlamydomonas reinhardtii Stimulation of CO2 fixation boosted TOR activity, whereas inhibition of the CBB cycle and photosynthesis down-regulated TOR. We uncovered a tight link between TOR activity and the endogenous level of a set of amino acids including Ala, Glu, Gln, Leu, and Val through the modulation of CO2 fixation and the use of amino acid synthesis inhibitors. Moreover, the finding that the Chlamydomonas starch-deficient mutant sta6 displayed disproportionate TOR activity and high levels of most amino acids, particularly Gln, further connected carbon assimilation and amino acids to TOR signaling. Thus, our results showed that CO2 fixation regulates TOR signaling, likely through the synthesis of key amino acids.
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41
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Mishra BS, Sharma M, Laxmi A. Role of sugar and auxin crosstalk in plant growth and development. PHYSIOLOGIA PLANTARUM 2022; 174:e13546. [PMID: 34480799 DOI: 10.1111/ppl.13546] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 08/27/2021] [Accepted: 08/30/2021] [Indexed: 05/07/2023]
Abstract
Under the natural environment, nutrient signals interact with phytohormones to coordinate and reprogram plant growth and survival. Sugars are important molecules that control almost all morphological and physiological processes in plants, ranging from seed germination to senescence. In addition to their functions as energy resources, osmoregulation, storage molecules, and structural components, sugars function as signaling molecules and interact with various plant signaling pathways, such as hormones, stress, and light to modulate growth and development according to fluctuating environmental conditions. Auxin, being an important phytohormone, is associated with almost all stages of the plant's life cycle and also plays a vital role in response to the dynamic environment for better growth and survival. In the previous years, substantial progress has been made that showed a range of common responses mediated by sugars and auxin signaling. This review discusses how sugar signaling affects auxin at various levels from its biosynthesis to perception and downstream gene activation. On the same note, the review also highlights the role of auxin signaling in fine-tuning sugar metabolism and carbon partitioning. Furthermore, we discussed the crosstalk between the two signaling machineries in the regulation of various biological processes, such as gene expression, cell cycle, development, root system architecture, and shoot growth. In conclusion, the review emphasized the role of sugar and auxin crosstalk in the regulation of several agriculturally important traits. Thus, engineering of sugar and auxin signaling pathways could potentially provide new avenues to manipulate for agricultural purposes.
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Affiliation(s)
- Bhuwaneshwar Sharan Mishra
- National Institute of Plant Genome Research, New Delhi, India
- Bhuwaneshwar Sharan Mishra, Ram Gulam Rai P. G. College Banktashiv, Affiliated to Deen Dayal Upadhyaya Gorakhpur University Gorakhpur, Deoria, Uttar Pradesh, India
| | - Mohan Sharma
- National Institute of Plant Genome Research, New Delhi, India
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, New Delhi, India
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42
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Subba P, Prasad TSK. Plant Phosphoproteomics: Known Knowns, Known Unknowns, and Unknown Unknowns of an Emerging Systems Science Frontier. OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2021; 25:750-769. [PMID: 34882020 DOI: 10.1089/omi.2021.0192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Plant systems science research depends on the dynamic functional maps of the biological substrates of plant phenotypes and host/environment interactions in diverse ecologies. In this context, high-resolution mass spectrometry platforms offer comprehensive insights into the molecular pathways regulated by protein phosphorylation. Reversible protein phosphorylation is a ubiquitous reaction in signal transduction mechanisms in biological systems. In contrast to human and animal biology research, a plethora of experimental options for functional mapping and regulation of plant biology are, however, not currently available. Plant phosphoproteomics is an emerging field of research that aims at addressing this gap in systems science and plant omics, and thus has a large scope to empower fundamental discoveries. To date, large-scale data-intensive identification of phosphorylation events in plants remained technically challenging. In this expert review, we present a critical analysis and overview of phosphoproteomic studies performed in the model plant Arabidopsis thaliana. We discuss the technical strategies used for the enrichment of phosphopeptides and methods used for their quantitative assessment. Various types of mass spectrometry data acquisition and fragmentation methods are also discussed. The insights gathered here can allow plant biology and systems science researchers to design high-throughput function-oriented experimental workflows that elucidate the regulatory signaling mechanisms impacting plant physiology and plant diseases.
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Affiliation(s)
- Pratigya Subba
- Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, India
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43
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Salazar-Díaz K, Dong Y, Papdi C, Ferruzca-Rubio EM, Olea-Badillo G, Ryabova LA, Dinkova TD. TOR senses and regulates spermidine metabolism during seedling establishment and growth in maize and Arabidopsis. iScience 2021; 24:103260. [PMID: 34765910 PMCID: PMC8571727 DOI: 10.1016/j.isci.2021.103260] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 04/23/2021] [Accepted: 10/11/2021] [Indexed: 12/14/2022] Open
Abstract
Spermidine (Spd) is a nitrogen sink and signaling molecule that plays pivotal roles in eukaryotic cell growth and must be finetuned to meet various energy demands. In eukaryotes, target of rapamycin (TOR) is a central nutrient sensor, especially N, and a master-regulator of growth and development. Here, we discovered that Spd stimulates the growth of maize and Arabidopsis seedlings through TOR signaling. Inhibition of Spd biosynthesis led to TOR inactivation and growth defects. Furthermore, disruption of a TOR complex partner RAPTOR1B abolished seedling growth stimulation by Spd. Strikingly, TOR activated by Spd promotes translation of key metabolic enzyme upstream open reading frame (uORF)-containing mRNAs, PAO and CuAO, by facilitating translation reinitiation and providing feedback to polyamine metabolism and TOR activation. The Spd-TOR relay protected young-age seedlings of maize from expeditious stress heat shock. Our results demonstrate Spd is an upstream effector of TOR kinase in planta and provide its potential application for crop protection. Spermidine (Spd) stimulates growth of maize and Arabidopsis by activating TOR signaling TOR stimulates translation efficiency of uORF-containing mRNAs involved in Spd catabolism TOR provides feedback to polyamine homeostasis in response to excess of Spd The Spd-TOR signaling axis protects maize seedlings from expeditious heat stress
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Affiliation(s)
- Kenia Salazar-Díaz
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, México
| | - Yihan Dong
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 67084 Strasbourg, France
| | - Csaba Papdi
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 67084 Strasbourg, France
| | - Ernesto Miguel Ferruzca-Rubio
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, México
| | - Grecia Olea-Badillo
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, México
| | - Lyubov A Ryabova
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 67084 Strasbourg, France
| | - Tzvetanka D Dinkova
- Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, México
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44
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Xie X, Wang Y, Datla R, Ren M. Auxin and Target of Rapamycin Spatiotemporally Regulate Root Organogenesis. Int J Mol Sci 2021; 22:ijms222111357. [PMID: 34768785 PMCID: PMC8583787 DOI: 10.3390/ijms222111357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 10/20/2021] [Indexed: 12/17/2022] Open
Abstract
The programs associated with embryonic roots (ERs), primary roots (PRs), lateral roots (LRs), and adventitious roots (ARs) play crucial roles in the growth and development of roots in plants. The root functions are involved in diverse processes such as water and nutrient absorption and their utilization, the storage of photosynthetic products, and stress tolerance. Hormones and signaling pathways play regulatory roles during root development. Among these, auxin is the most important hormone regulating root development. The target of rapamycin (TOR) signaling pathway has also been shown to play a key role in root developmental programs. In this article, the milestones and influential progress of studying crosstalk between auxin and TOR during the development of ERs, PRs, LRs and ARs, as well as their functional implications in root morphogenesis, development, and architecture, are systematically summarized and discussed.
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Affiliation(s)
- Xiulan Xie
- Labarotary of Space Biology, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, China; (X.X.); (Y.W.)
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Science of Zhengzhou University, Zhengzhou 450000, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
| | - Ying Wang
- Labarotary of Space Biology, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, China; (X.X.); (Y.W.)
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Science of Zhengzhou University, Zhengzhou 450000, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
| | - Raju Datla
- Global Institute for Food Security in Saskatoon, University of Saskatchewan, Saskatoon, SK S7N 0W9, Canada
- Correspondence: (R.D.); (M.R.)
| | - Maozhi Ren
- Labarotary of Space Biology, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, China; (X.X.); (Y.W.)
- Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Science of Zhengzhou University, Zhengzhou 450000, China
- Hainan Yazhou Bay Seed Laboratory, Sanya 572025, China
- Correspondence: (R.D.); (M.R.)
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45
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Castellano MM, Merchante C. Peculiarities of the regulation of translation initiation in plants. CURRENT OPINION IN PLANT BIOLOGY 2021; 63:102073. [PMID: 34186463 DOI: 10.1016/j.pbi.2021.102073] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 05/21/2021] [Accepted: 05/27/2021] [Indexed: 06/13/2023]
Abstract
Protein synthesis is a fundamental process for life and, as such, plays a crucial role in the adaptation to energy, developmentaland environmental conditions. For these reasons, and despite the general conservation of the eukaryotic translational machinery, it is not surprising that organisms with different lifestyles have evolved distinct mechanisms of regulation to adapt translation initiation to their intrinsic growth and development. Plants have clear peculiarities compared with other eukaryotes that have also extended to translation control. This review describes the plant-specific mechanisms for regulation of translation initiation, with a focus on those that modulate the eIF4F complexes, central translational regulatory hubs in all eukaryotes, and highlights the latest discoveries on the signaling pathways that regulate their constituents and activity.
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Affiliation(s)
- M Mar Castellano
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA, CSIC), Campus Montegancedo UPM, Pozuelo de Alarcón, Madrid, 28223, Spain.
| | - Catharina Merchante
- Instituto de Hortofruticultura Subtropical y Mediterránea "La Mayora" (IHSM-UMA-CSIC), Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Campus de Teatinos, Universidad de Málaga, Málaga, 29071, Spain.
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46
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Song Y, Alyafei MS, Masmoudi K, Jaleel A, Ren M. Contributions of TOR Signaling on Photosynthesis. Int J Mol Sci 2021; 22:ijms22168959. [PMID: 34445664 PMCID: PMC8396432 DOI: 10.3390/ijms22168959] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/22/2021] [Accepted: 07/29/2021] [Indexed: 12/15/2022] Open
Abstract
The target of rapamycin (TOR) protein kinase is an atypical Ser/Thr protein kinase and evolutionally conserved among yeasts, plants, and mammals. TOR has been established as a central hub for integrating nutrient, energy, hormone, and environmental signals in all the eukaryotes. Despite the conserved functions across eukaryotes, recent research has shed light on the multifaceted roles of TOR signaling in plant-specific functional and mechanistic features. One of the most specific features is the involvement of TOR in plant photosynthesis. The recent development of tools for the functional analysis of plant TOR has helped to uncover the involvement of TOR signaling in several steps preceding photoautotrophy and maintenance of photosynthesis. Here, we present recent novel findings relating to TOR signaling and its roles in regulating plant photosynthesis, including carbon nutrient sense, light absorptions, and leaf and chloroplast development. We also provide some gaps in our understanding of TOR function in photosynthesis that need to be addressed in the future.
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Affiliation(s)
- Yun Song
- School of Life Sciences, Liaocheng University, Liaocheng 252000, China;
| | - Mohammed Salem Alyafei
- Department of Integrative Agriculture, College of Food and Agriculture, United Arab Emirates University, Al Ain 15551, United Arab Emirates; (M.S.A.); (K.M.); (A.J.)
| | - Khaled Masmoudi
- Department of Integrative Agriculture, College of Food and Agriculture, United Arab Emirates University, Al Ain 15551, United Arab Emirates; (M.S.A.); (K.M.); (A.J.)
| | - Abdul Jaleel
- Department of Integrative Agriculture, College of Food and Agriculture, United Arab Emirates University, Al Ain 15551, United Arab Emirates; (M.S.A.); (K.M.); (A.J.)
| | - Maozhi Ren
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, China
- Correspondence: ; Tel.: +86-13527313471
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47
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Bryan de la Peña J, Kunder N, Lou TF, Chase R, Stanowick A, Barragan-Iglesias P, Pancrazio JJ, Campbell ZT. A Role for Translational Regulation by S6 Kinase and a Downstream Target in Inflammatory Pain. Br J Pharmacol 2021; 178:4675-4690. [PMID: 34355805 DOI: 10.1111/bph.15646] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Translational controls pervade neurobiology. Nociceptors play an integral role in the detection and propagation of pain signals. Nociceptors can undergo persistent changes in their intrinsic excitability. Pharmacologic disruption of nascent protein synthesis diminishes acute and chronic forms of pain-associated behaviors. Yet, the targets of translational controls that facilitate plasticity in nociceptors are unclear. EXPERIMENTAL APPROACH We used ribosome profiling to probe the translational landscape in DRG neurons after treatment of the inflammatory mediators NGF and IL-6. We validated the expression dynamics of c-Fos using immunoblotting and immunohistochemistry. Given that inflammation is known to stimulate mTOR signaling, we reasoned that downstream factors (e.g., ribosomal protein S6 kinase 1, S6K1) might control c-Fos levels. We utilized small-molecule inhibitors of S6K1 (DG2) or c-Fos (T-5224) to probe their effects on nociceptor activity in vitro using multi-electrode arrays (MEAs) and pain behavior in vivo using a hyperalgesic priming model. KEY RESULTS We demonstrate that c-Fos is expressed in sensory neurons. Inflammatory mediators that promote pain in both humans and rodents promote c-Fos translation. We demonstrate that the mTOR effector S6K1 is essential for c-Fos biosynthesis. Inhibition of S6K1 or c-Fos with small molecules diminish mechanical and thermal hypersensitivity in response to inflammatory cues. Additionally, both inhibitors reduce evoked nociceptor activity. CONCLUSION Our data reveal a novel role of S6K1 in modulating rapid response to inflammatory mediators, with c-Fos being one key downstream target. Targeting the S6 kinase pathway or c-Fos is an exciting new avenue for pain-modulating compounds.
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Affiliation(s)
- June Bryan de la Peña
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Nikesh Kunder
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Tzu-Fang Lou
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Rebecca Chase
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Alexander Stanowick
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Paulino Barragan-Iglesias
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA.,Department of Physiology and Pharmacology, Center for Basic Sciences, Autonomous University of Aguascalientes, Aguascalientes, Mexico
| | - Joseph J Pancrazio
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA.,Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
| | - Zachary T Campbell
- Department of Biological Sciences, University of Texas at Dallas, Richardson, TX, USA.,Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA.,Center for Advanced Pain Studies, University of Texas at Dallas, Richardson, TX, USA
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48
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Abstract
Nutrients are vital to life through intertwined sensing, signaling, and metabolic processes. Emerging research focuses on how distinct nutrient signaling networks integrate and coordinate gene expression, metabolism, growth, and survival. We review the multifaceted roles of sugars, nitrate, and phosphate as essential plant nutrients in controlling complex molecular and cellular mechanisms of dynamic signaling networks. Key advances in central sugar and energy signaling mechanisms mediated by the evolutionarily conserved master regulators HEXOKINASE1 (HXK1), TARGET OF RAPAMYCIN (TOR), and SNF1-RELATED PROTEIN KINASE1 (SNRK1) are discussed. Significant progress in primary nitrate sensing, calcium signaling, transcriptome analysis, and root-shoot communication to shape plant biomass and architecture are elaborated. Discoveries on intracellular and extracellular phosphate signaling and the intimate connections with nitrate and sugar signaling are examined. This review highlights the dynamic nutrient, energy, growth, and stress signaling networks that orchestrate systemwide transcriptional, translational, and metabolic reprogramming, modulate growth and developmental programs, and respond to environmental cues. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Lei Li
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, and Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114, USA; ,
| | - Kun-Hsiang Liu
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, and Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114, USA; , .,State Key Laboratory of Crop Stress Biology for Arid Areas, College of Life Sciences, and Institute of Future Agriculture, Northwest Agriculture & Forestry University, Yangling, Shaanxi 712100, China
| | - Jen Sheen
- Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, and Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114, USA; ,
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49
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Abstract
Auxin regulates the transcription of auxin-responsive genes by the TIR1/AFBs-Aux/IAA-ARF signaling pathway, and in this way facilitates plant growth and development. However, rapid, nontranscriptional responses to auxin that cannot be explained by this pathway have been reported. In this review, we focus on several examples of rapid auxin responses: (1) the triggering of changes in plasma membrane potential in various plant species and tissues, (2) inhibition of root growth, which also correlates with membrane potential changes, cytosolic Ca2+ spikes, and a rise of apoplastic pH, (3) the influence on endomembrane trafficking of PIN proteins and other membrane cargoes, and (4) activation of ROPs (Rho of plants) and their downstream effectors such as the cytoskeleton or vesicle trafficking. In most cases, the signaling pathway triggering the response is poorly understood. A role for the TIR1/AFBs in rapid root growth regulation is emerging, as well as the involvement of transmembrane kinases (TMKs) in the activation of ROPs. We discuss similarities and differences among these rapid responses and focus on their physiological significance, which remains an enigma in most cases.
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50
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Mancera-Martínez E, Dong Y, Makarian J, Srour O, Thiébeauld O, Jamsheer M, Chicher J, Hammann P, Schepetilnikov M, Ryabova LA. Phosphorylation of a reinitiation supporting protein, RISP, determines its function in translation reinitiation. Nucleic Acids Res 2021; 49:6908-6924. [PMID: 34133725 PMCID: PMC8266674 DOI: 10.1093/nar/gkab501] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 05/14/2021] [Accepted: 06/14/2021] [Indexed: 12/12/2022] Open
Abstract
Reinitiation supporting protein, RISP, interacts with 60S (60S ribosomal subunit) and eIF3 (eukaryotic initiation factor 3) in plants. TOR (target-of-rapamycin) mediates RISP phosphorylation at residue Ser267, favoring its binding to eL24 (60S ribosomal protein L24). In a viral context, RISP, when phosphorylated, binds the CaMV transactivator/ viroplasmin, TAV, to assist in an exceptional mechanism of reinitiation after long ORF translation. Moreover, we show here that RISP interacts with eIF2 via eIF2β and TOR downstream target 40S ribosomal protein eS6. A RISP phosphorylation knockout, RISP-S267A, binds preferentially eIF2β, and both form a ternary complex with eIF3a in vitro. Accordingly, transient overexpression in plant protoplasts of RISP-S267A, but not a RISP phosphorylation mimic, RISP-S267D, favors translation initiation. In contrast, RISP-S267D preferentially binds eS6, and, when bound to the C-terminus of eS6, can capture 60S in a highly specific manner in vitro, suggesting that it mediates 60S loading during reinitiation. Indeed, eS6-deficient plants are highly resistant to CaMV due to their reduced reinitiation capacity. Strikingly, an eS6 phosphomimic, when stably expressed in eS6-deficient plants, can fully restore the reinitiation deficiency of these plants in cellular and viral contexts. These results suggest that RISP function in translation (re)initiation is regulated by phosphorylation at Ser267.
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Affiliation(s)
- Eder Mancera-Martínez
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Yihan Dong
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Joelle Makarian
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Ola Srour
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Odon Thiébeauld
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Muhammed Jamsheer
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Johana Chicher
- Plateforme protéomique Strasbourg Esplanade FRC1589 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Philippe Hammann
- Plateforme protéomique Strasbourg Esplanade FRC1589 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Mikhail Schepetilnikov
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Lyubov A Ryabova
- Institut de biologie de moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
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