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Guillory A, Lopez-Obando M, Bouchenine K, Le Bris P, Lécureuil A, Pillot JP, Steinmetz V, Boyer FD, Rameau C, de Saint Germain A, Bonhomme S. SUPPRESSOR OF MAX2 1-LIKE (SMXL) homologs are MAX2-dependent repressors of Physcomitrium patens growth. THE PLANT CELL 2024; 36:1655-1672. [PMID: 38242840 PMCID: PMC11062456 DOI: 10.1093/plcell/koae009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 01/21/2024]
Abstract
SUPPRESSOR OF MAX2 (SMAX)1-LIKE (SMXL) proteins are a plant-specific clade of type I HSP100/Clp-ATPases. SMXL genes are present in virtually all land plant genomes. However, they have mainly been studied in angiosperms. In Arabidopsis (Arabidopsis thaliana), 3 functional SMXL subclades have been identified: SMAX1/SMXL2, SMXL345, and SMXL678. Of these, 2 subclades ensure endogenous phytohormone signal transduction. SMAX1/SMXL2 proteins are involved in KAI2 ligand (KL) signaling, while SMXL678 proteins are involved in strigolactone (SL) signaling. Many questions remain regarding the mode of action of these proteins, as well as their ancestral roles. We addressed these questions by investigating the functions of the 4 SMXL genes in the moss Physcomitrium patens. We demonstrate that PpSMXL proteins are involved in the conserved ancestral MAX2-dependent KL signaling pathway and negatively regulate growth. However, PpSMXL proteins expressed in Arabidopsis cannot replace SMAX1 or SMXL2 function in KL signaling, whereas they can functionally replace SMXL4 and SMXL5 and restore root growth. Therefore, the molecular functions of SMXL proteins are conserved, but their interaction networks are not. Moreover, the PpSMXLC/D clade positively regulates SL signal transduction in P. patens. Overall, our data reveal that SMXL proteins in moss mediate crosstalk between the SL and KL signaling pathways.
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Affiliation(s)
- Ambre Guillory
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan 31326, France
| | - Mauricio Lopez-Obando
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
- Institut de biologie moléculaire des plantes (IBMP), CNRS, University of Strasbourg, 12 rue du Général Zimmer, 67000 Strasbourg, France
| | - Khalissa Bouchenine
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Philippe Le Bris
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Alain Lécureuil
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Jean-Paul Pillot
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Vincent Steinmetz
- CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - François-Didier Boyer
- CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Catherine Rameau
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Alexandre de Saint Germain
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Sandrine Bonhomme
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
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2
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Wang JY, Chen GTE, Braguy J, Al-Babili S. Distinguishing the functions of canonical strigolactones as rhizospheric signals. TRENDS IN PLANT SCIENCE 2024:S1360-1385(24)00055-4. [PMID: 38521698 DOI: 10.1016/j.tplants.2024.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 02/12/2024] [Accepted: 02/29/2024] [Indexed: 03/25/2024]
Abstract
Strigolactones (SLs) act as regulators of plant architecture as well as signals in rhizospheric communications. Reduced availability of minerals, particularly phosphorus, leads to an increase in the formation and release of SLs that enable adaptation of root and shoot architecture to nutrient limitation and, simultaneously, attract arbuscular mycorrhizal fungi (AMF) for establishing beneficial symbiosis. Based on their chemical structure, SLs are designated as either canonical or non-canonical; however, the question of whether the two classes are also distinguished in their biological functions remained largely elusive until recently. In this review we summarize the latest advances in SL biosynthesis and highlight new findings pointing to rhizospheric signaling as the major function of canonical SLs.
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Affiliation(s)
- Jian You Wang
- The BioActives Lab, Center for Desert Agriculture, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Guan-Ting Erica Chen
- The BioActives Lab, Center for Desert Agriculture, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia; The Plant Science Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Justine Braguy
- The BioActives Lab, Center for Desert Agriculture, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia; The Plant Science Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Salim Al-Babili
- The BioActives Lab, Center for Desert Agriculture, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia; The Plant Science Program, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
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3
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Clark J, Bennett T. Cracking the enigma: understanding strigolactone signalling in the rhizosphere. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1159-1173. [PMID: 37623748 PMCID: PMC10860530 DOI: 10.1093/jxb/erad335] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
The rhizosphere is a complex physical and chemical interface between plants and their underground environment, both biotic and abiotic. Plants exude a large number of chemicals into the rhizosphere in order to manipulate these biotic and abiotic components. Among such chemicals are strigolactones, ancient signalling molecules that in flowering plants act as both internal hormones and external rhizosphere signals. Plants exude strigolactones to communicate with their preferred symbiotic partners and neighbouring plants, but at least some classes of parasitic organisms are able to 'crack' these private messages and eavesdrop on the signals. In this review, we examine the intentional consequences of strigolactone exudation, and also the unintentional consequences caused by eavesdroppers. We examine the molecular mechanisms by which strigolactones act within the rhizosphere, and attempt to understand the enigma of the strigolactone molecular diversity synthesized and exuded into the rhizosphere by plants. We conclude by looking at the prospects of using improved understanding of strigolactones in agricultural contexts.
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Affiliation(s)
- Jed Clark
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Tom Bennett
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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4
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Bennett T. Plant signalling: The case of the recycled receptor. Curr Biol 2024; 34:R82-R84. [PMID: 38320476 DOI: 10.1016/j.cub.2023.12.065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
RsbQ from bacteria and KAI2 from plants are highly related α/β-hydrolase proteins with unknown ligands. In a new study, Melville, Kamran et al. attempt to understand the ligand binding of RsbQ using knowledge from studies of KAI2, with surprising results.
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Affiliation(s)
- Tom Bennett
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
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5
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Lahari Z, van Boerdonk S, Omoboye OO, Reichelt M, Höfte M, Gershenzon J, Gheysen G, Ullah C. Strigolactone deficiency induces jasmonate, sugar and flavonoid phytoalexin accumulation enhancing rice defense against the blast fungus Pyricularia oryzae. THE NEW PHYTOLOGIST 2024; 241:827-844. [PMID: 37974472 DOI: 10.1111/nph.19354] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 10/05/2023] [Indexed: 11/19/2023]
Abstract
Strigolactones (SLs) are carotenoid-derived phytohormones that regulate plant growth and development. While root-secreted SLs are well-known to facilitate plant symbiosis with beneficial microbes, the role of SLs in plant interactions with pathogenic microbes remains largely unexplored. Using genetic and biochemical approaches, we demonstrate a negative role of SLs in rice (Oryza sativa) defense against the blast fungus Pyricularia oryzae (syn. Magnaporthe oryzae). We found that SL biosynthesis and perception mutants, and wild-type (WT) plants after chemical inhibition of SLs, were less susceptible to P. oryzae. Strigolactone deficiency also resulted in a higher accumulation of jasmonates, soluble sugars and flavonoid phytoalexins in rice leaves. Likewise, in response to P. oryzae infection, SL signaling was downregulated, while jasmonate and sugar content increased markedly. The jar1 mutant unable to synthesize jasmonoyl-l-isoleucine, and the coi1-18 RNAi line perturbed in jasmonate signaling, both accumulated lower levels of sugars. However, when WT seedlings were sprayed with glucose or sucrose, jasmonate accumulation increased, suggesting a reciprocal positive interplay between jasmonates and sugars. Finally, we showed that functional jasmonate signaling is necessary for SL deficiency to induce rice defense against P. oryzae. We conclude that a reduction in rice SL content reduces P. oryzae susceptibility by activating jasmonate and sugar signaling pathways, and flavonoid phytoalexin accumulation.
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Affiliation(s)
- Zobaida Lahari
- Department of Biotechnology, Ghent University, Ghent, 9000, Belgium
| | - Sarah van Boerdonk
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, 07745, Germany
| | - Olumide Owolabi Omoboye
- Department of Plants and Crops, Laboratory of Phytopathology, Ghent University, Ghent, 9000, Belgium
- Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, 220005, Nigeria
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, 07745, Germany
| | - Monica Höfte
- Department of Plants and Crops, Laboratory of Phytopathology, Ghent University, Ghent, 9000, Belgium
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, 07745, Germany
| | | | - Chhana Ullah
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, 07745, Germany
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6
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Mashiguchi K, Morita R, Tanaka K, Kodama K, Kameoka H, Kyozuka J, Seto Y, Yamaguchi S. Activation of Strigolactone Biosynthesis by the DWARF14-LIKE/KARRIKIN-INSENSITIVE2 Pathway in Mycorrhizal Angiosperms, but Not in Arabidopsis, a Non-mycorrhizal Plant. PLANT & CELL PHYSIOLOGY 2023; 64:1066-1078. [PMID: 37494415 PMCID: PMC10504576 DOI: 10.1093/pcp/pcad079] [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: 12/29/2022] [Revised: 07/14/2023] [Accepted: 07/24/2023] [Indexed: 07/28/2023]
Abstract
Strigolactones (SLs) are a class of plant hormones that regulate many aspects of plant growth and development. SLs also improve symbiosis with arbuscular mycorrhizal fungi (AMF) in the rhizosphere. Recent studies have shown that the DWARF14-LIKE (D14L)/KARRIKIN-INSENSITIVE2 (KAI2) family, paralogs of the SL receptor D14, are required for AMF colonization in several flowering plants, including rice. In this study, we found that (-)-GR5, a 2'S-configured enantiomer of a synthetic SL analog (+)-GR5, significantly activated SL biosynthesis in rice roots via D14L. This result is consistent with a recent report, showing that the D14L pathway positively regulates SL biosynthesis in rice. In fact, the SL levels tended to be lower in the roots of the d14l mutant under both inorganic nutrient-deficient and -sufficient conditions. We also show that the increase in SL levels by (-)-GR5 was observed in other mycorrhizal plant species. In contrast, the KAI2 pathway did not upregulate the SL level and the expression of SL biosynthetic genes in Arabidopsis, a non-mycorrhizal plant. We also examined whether the KAI2 pathway enhances SL biosynthesis in the liverwort Marchantia paleacea, where SL functions as a rhizosphere signaling molecule for AMF. However, the SL level and SL biosynthetic genes were not positively regulated by the KAI2 pathway. These results imply that the activation of SL biosynthesis by the D14L/KAI2 pathway has been evolutionarily acquired after the divergence of bryophytes to efficiently promote symbiosis with AMF, although we cannot exclude the possibility that liverworts have specifically lost this regulatory system.
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Affiliation(s)
- Kiyoshi Mashiguchi
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011 Japan
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
| | - Ryo Morita
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
| | - Kai Tanaka
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
| | - Kyoichi Kodama
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
| | - Hiromu Kameoka
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
| | - Junko Kyozuka
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
| | - Yoshiya Seto
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
- School of Agriculture, Meiji University, 1-1-1 Higashi-mita, Tama-ku, Kawasaki, Kanagawa, 214-8571 Japan
| | - Shinjiro Yamaguchi
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011 Japan
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi, 980-8577 Japan
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7
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Seo PJ, Lee HG, Choi HY, Lee S, Park CM. Complexity of SMAX1 signaling during seedling establishment. TRENDS IN PLANT SCIENCE 2023; 28:902-912. [PMID: 37069002 DOI: 10.1016/j.tplants.2023.03.014] [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: 08/19/2022] [Revised: 03/12/2023] [Accepted: 03/18/2023] [Indexed: 06/19/2023]
Abstract
Karrikins (KARs) are small butenolide compounds identified in the smoke of burning vegetation. Along with the stimulating effects on seed germination, KARs also regulate seedling vigor and adaptive behaviors, such as seedling morphogenesis, root hair development, and stress acclimation. The pivotal KAR signaling repressor, SUPPRESSOR OF MAX2 1 (SMAX1), plays central roles in these developmental and morphogenic processes through an extensive signaling network that governs seedling responses to endogenous and environmental cues. Here, we summarize the versatile roles of SMAX1 reported in recent years and discuss how SMAX1 integrates multiple growth hormone signals into optimizing seedling establishment. We also discuss the evolutionary relevance of the SMAX1-mediated signaling pathways during the colonization of aqueous plants to terrestrial environments.
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Affiliation(s)
- Pil Joon Seo
- Department of Chemistry, Seoul National University, Seoul 08826, Korea; Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Korea.
| | - Hong Gil Lee
- Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Korea
| | - Hye-Young Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Sangmin Lee
- Bio/Energy R&D Center, Korea Institute of Energy Research, Gwangju 61003, Korea
| | - Chung-Mo Park
- Department of Chemistry, Seoul National University, Seoul 08826, Korea; Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Korea.
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8
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Li LL, Li Z, Lou Y, Meiners SJ, Kong CH. (-)-Loliolide is a general signal of plant stress that activates jasmonate-related responses. THE NEW PHYTOLOGIST 2023; 238:2099-2112. [PMID: 36444519 DOI: 10.1111/nph.18644] [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: 08/29/2022] [Accepted: 11/24/2022] [Indexed: 05/04/2023]
Abstract
The production of defensive metabolites in plants can be induced by signaling chemicals released by neighboring plants. Induction is mainly known from volatile aboveground signals, with belowground signals and their underlying mechanisms largely unknown. We demonstrate that (-)-loliolide triggers defensive metabolite responses to competitors, herbivores, and pathogens in seven plant species. We further explore the transcriptional responses of defensive pathways to verify the signaling role of (-)-loliolide in wheat and rice models with well-known defensive metabolites and gene systems. In response to biotic and abiotic stressors, (-)-loliolide is produced and secreted by roots. This, in turn, induces the production of defensive compounds including phenolic acids, flavonoids, terpenoids, alkaloids, benzoxazinoids, and cyanogenic glycosides, regardless of plant species. (-)-Loliolide also triggers the expression of defense-related genes, accompanied by an increase in the concentration of jasmonic acid and hydrogen peroxide (H2 O2 ). Transcriptome profiling and inhibitor incubation indicate that (-)-loliolide-induced defense responses are regulated through pathways mediated by jasmonic acid, H2 O2 , and Ca 2+ . These findings argue that (-)-loliolide functions as a common belowground signal mediating chemical defense in plants. Such perception-dependent plant chemical defenses will yield critical insights into belowground signaling interactions.
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Affiliation(s)
- Lei-Lei Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Zheng Li
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Yonggen Lou
- Institute of Insect Science, Zhejiang University, Hangzhou, 310058, China
| | - Scott J Meiners
- Department of Biological Sciences, Eastern Illinois University, Charleston, IL, 61920, USA
| | - Chui-Hua Kong
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
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9
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Wallner ES, Tonn N, Shi D, Luzzietti L, Wanke F, Hunziker P, Xu Y, Jung I, Lopéz-Salmerón V, Gebert M, Wenzl C, Lohmann JU, Harter K, Greb T. OBERON3 and SUPPRESSOR OF MAX2 1-LIKE proteins form a regulatory module driving phloem development. Nat Commun 2023; 14:2128. [PMID: 37059727 PMCID: PMC10104830 DOI: 10.1038/s41467-023-37790-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 03/31/2023] [Indexed: 04/16/2023] Open
Abstract
Spatial specificity of cell fate decisions is central for organismal development. The phloem tissue mediates long-distance transport of energy metabolites along plant bodies and is characterized by an exceptional degree of cellular specialization. How a phloem-specific developmental program is implemented is, however, unknown. Here we reveal that the ubiquitously expressed PHD-finger protein OBE3 forms a central module with the phloem-specific SMXL5 protein for establishing the phloem developmental program in Arabidopsis thaliana. By protein interaction studies and phloem-specific ATAC-seq analyses, we show that OBE3 and SMXL5 proteins form a complex in nuclei of phloem stem cells where they promote a phloem-specific chromatin profile. This profile allows expression of OPS, BRX, BAM3, and CVP2 genes acting as mediators of phloem differentiation. Our findings demonstrate that OBE3/SMXL5 protein complexes establish nuclear features essential for determining phloem cell fate and highlight how a combination of ubiquitous and local regulators generate specificity of developmental decisions in plants.
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Affiliation(s)
- Eva-Sophie Wallner
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
- Gilbert Biological Sciences, Stanford University, Stanford, CA, 94305-5020, USA
| | - Nina Tonn
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Dongbo Shi
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
- Japan RIKEN Center for Sustainable Resource Science (CSRS), Yokohama, 230-0045, Japan
- Institute for Biochemistry and Biology (IBB), University of Potsdam, Potsdam, 14476, Germany
- Japan Science and Technology Agency (JST), Saitama, Kawaguchi, Japan
| | - Laura Luzzietti
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Friederike Wanke
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, 72076, Tübingen, Germany
| | - Pascal Hunziker
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Yingqiang Xu
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Ilona Jung
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Vadir Lopéz-Salmerón
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
- BD Bioscience, 69126, Heidelberg, Germany
| | - Michael Gebert
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Christian Wenzl
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Jan U Lohmann
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany
| | - Klaus Harter
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, 72076, Tübingen, Germany
| | - Thomas Greb
- Centre for Organismal Studies (COS), Heidelberg University, 69120, Heidelberg, Germany.
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10
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Waters MT, Nelson DC. Karrikin perception and signalling. THE NEW PHYTOLOGIST 2023; 237:1525-1541. [PMID: 36333982 DOI: 10.1111/nph.18598] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
Karrikins (KARs) are a class of butenolide compounds found in smoke that were first identified as seed germination stimulants for fire-following species. Early studies of KARs classified the germination and postgermination responses of many plant species and investigated crosstalk with plant hormones that regulate germination. The discovery that Arabidopsis thaliana responds to KARs laid the foundation for identifying mutants with altered KAR responses. Genetic analysis of KAR signalling revealed an unexpected link to strigolactones (SLs), a class of carotenoid-derived plant hormones. Substantial progress has since been made towards understanding how KARs are perceived and regulate plant growth, in no small part due to advances in understanding SL perception. KAR and SL signalling systems are evolutionarily related and retain a high degree of similarity. There is strong evidence that KARs are natural analogues of an endogenous signal(s), KAI2 ligand (KL), which remains unknown. KAR/KL signalling regulates many developmental processes in plants including germination, seedling photomorphogenesis, and root and root hair growth. KAR/KL signalling also affects abiotic stress responses and arbuscular mycorrhizal symbiosis. Here, we summarise the current knowledge of KAR/KL signalling and discuss current controversies and unanswered questions in this field.
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Affiliation(s)
- Mark T Waters
- School of Molecular Sciences, University of Western Australia, Perth, WA, 6009, Australia
| | - David C Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
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11
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Liu B, Liu K, Chen X, Xiao D, Wang T, Yang Y, Shuai H, Wu S, Yuan L, Chen L. Comparative Transcriptome Analysis Reveals the Interaction of Sugar and Hormone Metabolism Involved in the Root Hair Morphogenesis of the Endangered Fir Abies beshanzuensis. PLANTS (BASEL, SWITZERLAND) 2023; 12:276. [PMID: 36678989 PMCID: PMC9862426 DOI: 10.3390/plants12020276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/26/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
Abies beshanzuensis, an extremely rare and critically endangered plant with only three wild adult trees globally, is strongly mycorrhizal-dependent, leading to difficulties in protection and artificial breeding without symbiosis. Root hair morphogenesis plays an important role in the survival of mycorrhizal symbionts. Due to the lack of an effective genome and transcriptome of A. beshanzuensis, the molecular signals involved in the root hair development remain unknown, which hinders its endangered mechanism analysis and protection. Herein, transcriptomes of radicles with root hair (RH1) and without root hair (RH0) from A. beshanzuensis in vitro plantlets were primarily established. Functional annotation and differentially expressed gene (DEG) analysis showed that the two phenotypes have highly differentially expressed gene clusters. Transcriptome divergence identified hormone and sugar signaling primarily involved in root hair morphogenesis of A. beshanzuensis. Weighted correlation network analysis (WGCNA) coupled with quantitative real-time PCR (qRT-PCR) found that two hormone-sucrose-root hair modules were linked by IAA17, and SUS was positioned in the center of the regulation network, co-expressed with SRK2E in hormone transduction and key genes related to root hair morphogenesis. Our results contribute to better understanding of the molecular mechanisms of root hair development and offer new insights into deciphering the survival mechanism of A. beshanzuensis and other endangered species, utilizing root hair as a compensatory strategy instead of poor mycorrhizal growth.
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Affiliation(s)
- Bin Liu
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Ke Liu
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Xiaorong Chen
- Qingyuan Conservation Center of Qianjiangyuan-Baishanzu National Park, Qingyuan 323800, China
| | - Duohong Xiao
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Tingjin Wang
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yang Yang
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Hui Shuai
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Sumei Wu
- Qingyuan Conservation Center of Qianjiangyuan-Baishanzu National Park, Qingyuan 323800, China
| | - Lu Yuan
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Liping Chen
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
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12
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Chiu CH, Roszak P, Orvošová M, Paszkowski U. Arbuscular mycorrhizal fungi induce lateral root development in angiosperms via a conserved set of MAMP receptors. Curr Biol 2022; 32:4428-4437.e3. [PMID: 36115339 DOI: 10.1016/j.cub.2022.08.069] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 05/06/2022] [Accepted: 08/23/2022] [Indexed: 10/14/2022]
Abstract
Root systems regulate their branching patterns in response to environmental stimuli. Lateral root development in both monocotyledons and dicotyledons is enhanced in response to inoculation with arbuscular mycorrhizal (AM) fungi, which has been interpreted as a developmental response to specific, symbiosis-activating chitinaceous signals. Here, we report that generic instead of symbiosis-specific, chitin-derived molecules trigger lateral root formation. We demonstrate that this developmental response requires the well-known microbe-associated molecular pattern (MAMP) receptor, ChitinElicitorReceptorKinase 1 (CERK1), in rice, Medicago truncatula, and Lotus japonicus, as well as the non-host of AM fungi, Arabidopsis thaliana, lending further support for a broadly conserved signal transduction mechanism across angiosperms. Using rice mutants impaired in strigolactone biosynthesis and signaling, we show that strigolactone signaling is necessary to regulate this developmental response. Rice CERK1 operates together with either Chitin Elicitor Binding Protein (CEBiP) or Nod Factor Receptor 5 (NFR5) in immunity and symbiosis signaling, respectively; for the lateral root response, however, all three LysM receptors are required. Our work, therefore, reveals an overlooked but a conserved role of LysM receptors integrating MAMP perception with developmental responses in plants, an ability that might influence the interaction between roots and the rhizosphere biota.
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Affiliation(s)
- Chai Hao Chiu
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK.
| | - Pawel Roszak
- Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge CB2 1LR, UK
| | - Martina Orvošová
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | - Uta Paszkowski
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK.
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13
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Bürger M, Honda K, Kondoh Y, Hong S, Watanabe N, Osada H, Chory J. Crystal structure of Arabidopsis DWARF14-LIKE2 (DLK2) reveals a distinct substrate binding pocket architecture. PLANT DIRECT 2022; 6:e446. [PMID: 36172078 PMCID: PMC9470386 DOI: 10.1002/pld3.446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/14/2022] [Accepted: 08/17/2022] [Indexed: 06/16/2023]
Abstract
In Arabidopsis thaliana, the Sigma factor B regulator RsbQ-like family of α/β hydrolases contains the strigolactone (SL) receptor DWARF14 (AtD14), the karrikin receptor KARRIKIN INSENSITIVE2 (AtKAI2), and DWARF14-LIKE2 (AtDLK2), a protein of unknown function. Despite very similar protein folds, AtD14 and AtKAI2 differ in size and architecture of their ligand binding pockets, influencing their substrate specificity. We present the 1.5 Å crystal structure of AtDLK2, revealing the smallest ligand binding pocket in the protein family, bordered by two unique glycine residues. We identified a gatekeeper residue in the protein's lid domain and present a pyrrolo-quinoline-dione compound that inhibits AtDLK2's enzymatic activity.
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Affiliation(s)
- Marco Bürger
- Plant Biology LaboratorySalk Institute for Biological StudiesLa JollaCaliforniaUSA
| | - Kaori Honda
- Chemical Biology Research GroupRIKEN Centre for Sustainable Resource ScienceWakoSaitamaJapan
| | - Yasumitsu Kondoh
- Chemical Biology Research GroupRIKEN Centre for Sustainable Resource ScienceWakoSaitamaJapan
| | - Sharon Hong
- Plant Biology LaboratorySalk Institute for Biological StudiesLa JollaCaliforniaUSA
| | - Nobumoto Watanabe
- Bioprobe Application Research UnitRIKEN Centre for Sustainable Resource ScienceWakoSaitamaJapan
| | - Hiroyuki Osada
- Chemical Biology Research GroupRIKEN Centre for Sustainable Resource ScienceWakoSaitamaJapan
| | - Joanne Chory
- Plant Biology LaboratorySalk Institute for Biological StudiesLa JollaCaliforniaUSA
- Howard Hughes Medical InstituteSalk Institute for Biological StudiesLa JollaCaliforniaUSA
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14
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Ogawa S, Cui S, White ARF, Nelson DC, Yoshida S, Shirasu K. Strigolactones are chemoattractants for host tropism in Orobanchaceae parasitic plants. Nat Commun 2022; 13:4653. [PMID: 35970835 PMCID: PMC9378612 DOI: 10.1038/s41467-022-32314-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 07/26/2022] [Indexed: 12/17/2022] Open
Abstract
Parasitic plants are worldwide threats that damage major agricultural crops. To initiate infection, parasitic plants have developed the ability to locate hosts and grow towards them. This ability, called host tropism, is critical for parasite survival, but its underlying mechanism remains mostly unresolved. To characterise host tropism, we used the model facultative root parasite Phtheirospermum japonicum, a member of the Orobanchaceae. Here, we show that strigolactones (SLs) function as host-derived chemoattractants. Chemotropism to SLs is also found in Striga hermonthica, a parasitic member of the Orobanchaceae, but not in non-parasites. Intriguingly, chemotropism to SLs in P. japonicum is attenuated in ammonium ion-rich conditions, where SLs are perceived, but the resulting asymmetrical accumulation of the auxin transporter PIN2 is diminished. P. japonicum encodes putative receptors that sense exogenous SLs, whereas expression of a dominant-negative form reduces its chemotropic ability. We propose a function for SLs as navigators for parasite roots.
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Affiliation(s)
- Satoshi Ogawa
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan
| | - Songkui Cui
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Alexandra R F White
- Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
| | - David C Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
| | - Satoko Yoshida
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.,PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
| | - Ken Shirasu
- RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045, Japan. .,Graduate School of Science, The University of Tokyo, Tokyo, 113-0033, Japan.
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15
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Bonhomme S, Guillory A. Synthesis and signalling of strigolactone and KAI2-ligand signals in bryophytes. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:4487-4495. [PMID: 35524989 DOI: 10.1093/jxb/erac186] [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: 12/17/2021] [Accepted: 05/04/2022] [Indexed: 06/14/2023]
Abstract
Strigolactones (SLs), long known as butenolide rhizospheric signals, have been recognized since 2008 as a class of hormones regulating many aspects of plant development. Many authors also anticipate 'KAI2-ligand' (KL) as a novel class of phytohormones; however, this ligand remains elusive. Core genes of SL and KL pathways, first described in angiosperms, are found in all land plants and some even in green algae. This review reports current knowledge of these pathways in bryophytes. Data on the pathways mostly come from two models: the moss Physcomitrium patens and the liverwort Marchantia. Gene targeting methods have allowed functional analyses of both models. Recent work in Marchantia suggests that SLs' ancestral role was to recruit beneficial microbes as arbuscular mycorrhizal fungi. In contrast, the hormonal role of SLs observed in P. patens is probably a result of convergent evolution. Evidence for a functional KL pathway in both bryophyte models is very recent. Nevertheless, many unknowns remain and warrant a more extensive investigation of SL and KL pathways in various land plant lineages.
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Affiliation(s)
- Sandrine Bonhomme
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Ambre Guillory
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
- Laboratoire des Interactions Plantes - Microbes - Environnement (LIPME), Université de Toulouse, INRAE, CNRS, 24 Chemin de Borde Rouge, 31320 Castanet-Tolosan, France
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16
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Probing strigolactone perception mechanisms with rationally designed small-molecule agonists stimulating germination of root parasitic weeds. Nat Commun 2022; 13:3987. [PMID: 35810153 PMCID: PMC9271048 DOI: 10.1038/s41467-022-31710-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 06/29/2022] [Indexed: 01/11/2023] Open
Abstract
The development of potent strigolactone (SL) agonists as suicidal germination inducers could be a useful strategy for controlling root parasitic weeds, but uncertainty about the SL perception mechanism impedes real progress. Here we describe small-molecule agonists that efficiently stimulate Phelipanchce aegyptiaca, and Striga hermonthica, germination in concentrations as low as 10−8 to 10−17 M. We show that full efficiency of synthetic SL agonists in triggering signaling through the Striga SL receptor, ShHTL7, depends on the receptor-catalyzed hydrolytic reaction of the agonists. Additionally, we reveal that the stereochemistry of synthetic SL analogs affects the hydrolytic ability of ShHTL7 by influencing the probability of the privileged conformations of ShHTL7. Importantly, an alternative ShHTL7-mediated hydrolysis mechanism, proceeding via nucleophilic attack of the NE2 atom of H246 to the 2′C of the D-ring, is reported. Together, our findings provide insight into SL hydrolysis and structure-perception mechanisms, and potent suicide germination stimulants, which would contribute to the elimination of the noxious parasitic weeds. Strigolactone agonists could potentially help control noxious weeds by promoting suicidal germination. Here the authors describe a series of small molecule agonists that stimulate germination via the Striga ShHTL7 receptor and show that stereochemistry and hydrolysis-independent signalling mediate potency.
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17
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Kodama K, Rich MK, Yoda A, Shimazaki S, Xie X, Akiyama K, Mizuno Y, Komatsu A, Luo Y, Suzuki H, Kameoka H, Libourel C, Keller J, Sakakibara K, Nishiyama T, Nakagawa T, Mashiguchi K, Uchida K, Yoneyama K, Tanaka Y, Yamaguchi S, Shimamura M, Delaux PM, Nomura T, Kyozuka J. An ancestral function of strigolactones as symbiotic rhizosphere signals. Nat Commun 2022. [PMID: 35803942 DOI: 10.1101/2021.08.20.457034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants. BSB synthesis is enhanced at AM symbiosis permissive conditions and BSB deficient mutants are impaired in AM symbiosis. In contrast, the absence of BSB synthesis has little effect on the growth and gene expression. We show that the introduction of the SL receptor of Arabidopsis renders M. paleacea cells BSB-responsive. These results suggest that BSB is not perceived by M. paleacea cells due to the lack of cognate SL receptors. We propose that SLs originated as AM symbiosis-inducing rhizosphere signaling molecules and were later recruited as plant hormone.
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Affiliation(s)
- Kyoichi Kodama
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Mélanie K Rich
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France
| | - Akiyoshi Yoda
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan
| | - Shota Shimazaki
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Xiaonan Xie
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan
| | - Kohki Akiyama
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan
| | - Yohei Mizuno
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Aino Komatsu
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Yi Luo
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Hidemasa Suzuki
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Hiromu Kameoka
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Cyril Libourel
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France
| | - Jean Keller
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France
| | | | - Tomoaki Nishiyama
- Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, Japan
| | | | | | - Kenichi Uchida
- Department of Biosciences, Teikyo University, Tochigi, Japan
| | - Kaori Yoneyama
- Graduate School of Agriculture, Ehime University, Ehime, Japan
| | - Yoshikazu Tanaka
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | | | - Masaki Shimamura
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Pierre-Marc Delaux
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France.
| | - Takahito Nomura
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.
- Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan.
| | - Junko Kyozuka
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan.
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18
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Kodama K, Rich MK, Yoda A, Shimazaki S, Xie X, Akiyama K, Mizuno Y, Komatsu A, Luo Y, Suzuki H, Kameoka H, Libourel C, Keller J, Sakakibara K, Nishiyama T, Nakagawa T, Mashiguchi K, Uchida K, Yoneyama K, Tanaka Y, Yamaguchi S, Shimamura M, Delaux PM, Nomura T, Kyozuka J. An ancestral function of strigolactones as symbiotic rhizosphere signals. Nat Commun 2022; 13:3974. [PMID: 35803942 PMCID: PMC9270392 DOI: 10.1038/s41467-022-31708-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 06/29/2022] [Indexed: 11/23/2022] Open
Abstract
In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants. BSB synthesis is enhanced at AM symbiosis permissive conditions and BSB deficient mutants are impaired in AM symbiosis. In contrast, the absence of BSB synthesis has little effect on the growth and gene expression. We show that the introduction of the SL receptor of Arabidopsis renders M. paleacea cells BSB-responsive. These results suggest that BSB is not perceived by M. paleacea cells due to the lack of cognate SL receptors. We propose that SLs originated as AM symbiosis-inducing rhizosphere signaling molecules and were later recruited as plant hormone. Strigolactones (SLs) regulate angiosperm development and promote symbiosis with arbuscular mycorrhizae. Here the authors show that bryosymbiol, an SL present in bryophytes and angiosperms, promotes AM symbiosis in Marchantia paleacea suggesting an ancestral function of SLs as rhizosphere signals.
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Affiliation(s)
- Kyoichi Kodama
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Mélanie K Rich
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France
| | - Akiyoshi Yoda
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.,Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan
| | - Shota Shimazaki
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Xiaonan Xie
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.,Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan
| | - Kohki Akiyama
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan
| | - Yohei Mizuno
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Aino Komatsu
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Yi Luo
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Hidemasa Suzuki
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Hiromu Kameoka
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Cyril Libourel
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France
| | - Jean Keller
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France
| | | | - Tomoaki Nishiyama
- Research Center for Experimental Modeling of Human Disease, Kanazawa University, Kanazawa, Japan
| | | | | | - Kenichi Uchida
- Department of Biosciences, Teikyo University, Tochigi, Japan
| | - Kaori Yoneyama
- Graduate School of Agriculture, Ehime University, Ehime, Japan
| | - Yoshikazu Tanaka
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | | | - Masaki Shimamura
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Pierre-Marc Delaux
- LRSV, Université de Toulouse, CNRS, UPS, Toulouse INP, Auzeville-Tolosane, France.
| | - Takahito Nomura
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan. .,Center for Bioscience Research and Education, Utsunomiya University, Tochigi, Japan.
| | - Junko Kyozuka
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan.
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19
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Yoneyama K, Xie X, Nomura T, Yoneyama K, Bennett T. Supra-organismal regulation of strigolactone exudation and plant development in response to rhizospheric cues in rice. Curr Biol 2022; 32:3601-3608.e3. [PMID: 35839765 DOI: 10.1016/j.cub.2022.06.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 04/28/2022] [Accepted: 06/15/2022] [Indexed: 01/10/2023]
Abstract
Plants have evolved elaborate mechanisms to detect neighboring plants, which typically involve the perception of "cues" inadvertently produced by the neighbor.1 Strigolactones are hormonal signaling molecules2,3 that are also exuded into the rhizosphere by most flowering plant species to promote arbuscular mycorrhizal symbioses.4 Since flowering plants have an endogenous perception system for strigolactones,5 strigolactones are obvious candidates to act as a cue for neighbor presence, but have not been shown to act as such. To test this hypothesis in rice plants, we quantified two major strigolactones of rice plants, orobanchol and 4-deoxyorobanchol, in root exudates by using LC-MS/MS (MRM) and examined feedback regulation of strigolactone biosynthesis and changes in shoot branching phenotypes in rice plants grown at different densities in hydroponics and soil culture. We show that the presence of neighboring plants, or greater root volume, results in rapidly induced changes in strigolactone biosynthesis, sensitivity, and exudation and the subsequent longer-term changes in shoot architecture. These changes require intact strigolactone biosynthesis in neighboring plants and intact strigolactone signaling in focal plants. These results suggest that strigolactone biosynthesis and exudation in rice plants are driven by supra-organismal environmental strigolactone levels. Strigolactones thus act as a cue for neighbor presence in rice plants, but also seem to act as a more general root density-sensing mechanism in flowering plants that integrates soil volume and neighbor density and allows plants to adapt to the limitations of the rhizosphere.
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Affiliation(s)
- Kaori Yoneyama
- Graduate School of Agriculture, Ehime University, Matsuyama 790-8566, Japan; Japan Science and Technology, PRESTO, Kawaguchi 332-0012, Japan.
| | - Xiaonan Xie
- Center for Bioscience Research and Education, Utsunomiya University, Utsunomiya 321-8505, Japan
| | - Takahito Nomura
- Center for Bioscience Research and Education, Utsunomiya University, Utsunomiya 321-8505, Japan
| | - Koichi Yoneyama
- Center for Bioscience Research and Education, Utsunomiya University, Utsunomiya 321-8505, Japan
| | - Tom Bennett
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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20
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Hamon‐Josse M, Villaécija‐Aguilar JA, Ljung K, Leyser O, Gutjahr C, Bennett T. KAI2 regulates seedling development by mediating light-induced remodelling of auxin transport. THE NEW PHYTOLOGIST 2022; 235:126-140. [PMID: 35313031 PMCID: PMC9320994 DOI: 10.1111/nph.18110] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/05/2022] [Indexed: 05/13/2023]
Abstract
Photomorphogenic remodelling of seedling growth is a key developmental transition in the plant life cycle. The α/β-hydrolase signalling protein KARRIKIN-INSENSITIVE2 (KAI2), a close homologue of the strigolactone receptor DWARF14 (D14), is involved in this process, but it is unclear how the effects of KAI2 on development are mediated. Here, using a combination of physiological, pharmacological, genetic and imaging approaches in Arabidopsis thaliana (Heynh.) we show that kai2 phenotypes arise because of a failure to downregulate auxin transport from the seedling shoot apex towards the root system, rather than a failure to respond to light per se. We demonstrate that KAI2 controls the light-induced remodelling of the PIN-mediated auxin transport system in seedlings, promoting a reduction in PIN7 abundance in older tissues, and an increase of PIN1/PIN2 abundance in the root meristem. We show that removing PIN3, PIN4 and PIN7 from kai2 mutants, or pharmacological inhibition of auxin transport and synthesis, is sufficient to suppress most kai2 seedling phenotypes. We conclude that KAI2 regulates seedling morphogenesis by its effects on the auxin transport system. We propose that KAI2 is not required for the light-mediated changes in PIN gene expression but is required for the appropriate changes in PIN protein abundance within cells.
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Affiliation(s)
- Maxime Hamon‐Josse
- School of BiologyFaculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
| | | | - Karin Ljung
- Department of Forest Genetics and Plant PhysiologyUmeå Plant Science CentreSwedish University of Agricultural SciencesSE‐901 83UmeåSweden
| | - Ottoline Leyser
- Sainsbury Laboratory Cambridge UniversityBateman StreetCambridgeCB2 1LRUK
| | - Caroline Gutjahr
- Plant GeneticsTUM School of Life SciencesTechnical University of Munich (TUM)Emil Ramann Str. 485354FreisingGermany
- GeneticsFaculty of BiologyLMU MunichGrosshaderner St. 482152MartinsriedGermany
| | - Tom Bennett
- School of BiologyFaculty of Biological SciencesUniversity of LeedsLeedsLS2 9JTUK
- Sainsbury Laboratory Cambridge UniversityBateman StreetCambridgeCB2 1LRUK
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21
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White ARF, Mendez JA, Khosla A, Nelson DC. Rapid analysis of strigolactone receptor activity in a Nicotiana benthamiana dwarf14 mutant. PLANT DIRECT 2022; 6:e389. [PMID: 35355884 PMCID: PMC8948499 DOI: 10.1002/pld3.389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 12/03/2021] [Accepted: 02/17/2022] [Indexed: 05/29/2023]
Abstract
DWARF14 (D14) is an ɑ/β-hydrolase and receptor for the plant hormone strigolactone (SL) in angiosperms. Upon SL perception, D14 works with MORE AXILLARY GROWTH2 (MAX2) to trigger polyubiquitination and degradation of DWARF53(D53)-type proteins in the SUPPRESSOR OF MAX2 1-LIKE (SMXL) family. We used CRISPR-Cas9 to generate knockout alleles of the two homoeologous D14 genes in the Nicotiana benthamiana genome. The Nbd14a,b double mutant had several phenotypes that are consistent with the loss of SL perception in other plants, including increased axillary bud outgrowth, reduced height, shortened petioles, and smaller leaves. A ratiometric fluorescent reporter system was used to monitor degradation of SMXL7 from Arabidopsis thaliana (AtSMXL7) after transient expression in N. benthamiana and treatment with the strigolactone analog GR24. AtSMXL7 was degraded after treatment with GR245DS, which has the stereochemical configuration of natural SLs, as well as its enantiomer GR24 ent-5DS. In Nbd14a,b leaves, AtSMXL7 abundance was unaffected by rac-GR24 or either GR24 stereoisomer. Transient coexpression of AtD14 with the AtSMXL7 reporter in Nbd14a,b restored the degradation response to rac-GR24, but required an active catalytic triad. We used this platform to evaluate the ability of several AtD14 mutants that had not been characterized in plants to target AtSMXL7 for degradation.
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Affiliation(s)
- Alexandra R. F. White
- Department of Botany and Plant SciencesUniversity of CaliforniaRiversideCaliforniaUSA
| | - Jose A. Mendez
- Department of Botany and Plant SciencesUniversity of CaliforniaRiversideCaliforniaUSA
| | - Aashima Khosla
- Department of Botany and Plant SciencesUniversity of CaliforniaRiversideCaliforniaUSA
| | - David C. Nelson
- Department of Botany and Plant SciencesUniversity of CaliforniaRiversideCaliforniaUSA
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22
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Temmerman A, Guillory A, Bonhomme S, Goormachtig S, Struk S. Masks Start to Drop: Suppressor of MAX2 1-Like Proteins Reveal Their Many Faces. FRONTIERS IN PLANT SCIENCE 2022; 13:887232. [PMID: 35645992 PMCID: PMC9133912 DOI: 10.3389/fpls.2022.887232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/25/2022] [Indexed: 05/11/2023]
Abstract
Although the main players of the strigolactone (SL) signaling pathway have been characterized genetically, how they regulate plant development is still poorly understood. Of central importance are the SUPPRESSOR OF MAX2 1-LIKE (SMXL) proteins that belong to a family of eight members in Arabidopsis thaliana, of which one subclade is involved in SL signaling and another one in the pathway of the chemically related karrikins. Through proteasomal degradation of these SMXLs, triggered by either DWARF14 (D14) or KARRIKIN INSENSITIVE2 (KAI2), several physiological processes are controlled, such as, among others, shoot and root architecture, seed germination, and seedling photomorphogenesis. Yet another clade has been shown to be involved in vascular development, independently of the D14 and KAI2 actions and not relying on proteasomal degradation. Despite their role in several aspects of plant development, the exact molecular mechanisms by which SMXLs regulate them are not completely unraveled. To fill the major knowledge gap in understanding D14 and KAI2 signaling, SMXLs are intensively studied, making it challenging to combine all the insights into a coherent characterization of these important proteins. To this end, this review provides an in-depth exploration of the recent data regarding their physiological function, evolution, structure, and molecular mechanism. In addition, we propose a selection of future perspectives, focusing on the apparent localization of SMXLs in subnuclear speckles, as observed in transient expression assays, which we couple to recent advances in the field of biomolecular condensates and liquid-liquid phase separation.
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Affiliation(s)
- Arne Temmerman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB-Center for Plant Systems Biology, Ghent, Belgium
| | - Ambre Guillory
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), Versailles, France
- LIPME, Université de Toulouse, INRAE, CNRS, Castanet-Tolosan, France
| | - Sandrine Bonhomme
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), Versailles, France
| | - Sofie Goormachtig
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB-Center for Plant Systems Biology, Ghent, Belgium
| | - Sylwia Struk
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB-Center for Plant Systems Biology, Ghent, Belgium
- *Correspondence: Sylwia Struk,
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23
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Mishev K, Dobrev PI, Lacek J, Filepová R, Yuperlieva-Mateeva B, Kostadinova A, Hristeva T. Hormonomic Changes Driving the Negative Impact of Broomrape on Plant Host Interactions with Arbuscular Mycorrhizal Fungi. Int J Mol Sci 2021; 22:13677. [PMID: 34948474 PMCID: PMC8708155 DOI: 10.3390/ijms222413677] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 12/02/2022] Open
Abstract
Belowground interactions of plants with other organisms in the rhizosphere rely on extensive small-molecule communication. Chemical signals released from host plant roots ensure the development of beneficial arbuscular mycorrhizal (AM) fungi which in turn modulate host plant growth and stress tolerance. However, parasitic plants have adopted the capacity to sense the same signaling molecules and to trigger their own seed germination in the immediate vicinity of host roots. The contribution of AM fungi and parasitic plants to the regulation of phytohormone levels in host plant roots and root exudates remains largely obscure. Here, we studied the hormonome in the model system comprising tobacco as a host plant, Phelipanche spp. as a holoparasitic plant, and the AM fungus Rhizophagus irregularis. Co-cultivation of tobacco with broomrape and AM fungi alone or in combination led to characteristic changes in the levels of endogenous and exuded abscisic acid, indole-3-acetic acid, cytokinins, salicylic acid, and orobanchol-type strigolactones. The hormonal content in exudates of broomrape-infested mycorrhizal roots resembled that in exudates of infested non-mycorrhizal roots and differed from that observed in exudates of non-infested mycorrhizal roots. Moreover, we observed a significant reduction in AM colonization of infested tobacco plants, pointing to a dominant role of the holoparasite within the tripartite system.
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Affiliation(s)
- Kiril Mishev
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (B.Y.-M.); (A.K.)
| | - Petre I. Dobrev
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.)
| | - Jozef Lacek
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.)
| | - Roberta Filepová
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany of the Czech Academy of Sciences, 165 02 Praha, Czech Republic; (P.I.D.); (J.L.); (R.F.)
| | - Bistra Yuperlieva-Mateeva
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (B.Y.-M.); (A.K.)
| | - Anelia Kostadinova
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (B.Y.-M.); (A.K.)
| | - Tsveta Hristeva
- Tobacco and Tobacco Products Institute, Agricultural Academy, 4108 Plovdiv, Bulgaria
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24
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Villaécija-Aguilar JA, Körösy C, Maisch L, Hamon-Josse M, Petrich A, Magosch S, Chapman P, Bennett T, Gutjahr C. KAI2 promotes Arabidopsis root hair elongation at low external phosphate by controlling local accumulation of AUX1 and PIN2. Curr Biol 2021; 32:228-236.e3. [PMID: 34758285 DOI: 10.1016/j.cub.2021.10.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/17/2021] [Accepted: 10/20/2021] [Indexed: 11/30/2022]
Abstract
Root hair (RH) growth to increase the absorptive root surface area is a key adaptation of plants to limiting phosphate availability in soils. Despite the importance of this trait, especially for seedling survival, little is known about the molecular events connecting phosphate starvation sensing and RH growth regulation. KARRIKIN INSENSITIVE2 (KAI2), an α/β-hydrolase receptor of a yet-unknown plant hormone ("KAI2-ligand" [KL]), is required for RH elongation.1 KAI2 interacts with the F-box protein MORE AXILLIARY BRANCHING2 (MAX2) to target regulatory proteins of the SUPPRESSOR of MAX2 1 (SMAX1) family for degradation.2 Here, we demonstrate that Pi starvation increases KL signaling in Arabidopsis roots through transcriptional activation of KAI2 and MAX2. Both genes are required for RH elongation under these conditions, while smax1 smxl2 mutants have constitutively long RHs, even at high Pi availability. Attenuated RH elongation in kai2 mutants is explained by reduced shootward auxin transport from the root tip resulting in reduced auxin signaling in the RH zone, caused by an inability to increase localized accumulation of the auxin importer AUXIN TRANSPORTER PROTEIN1 (AUX1) and the auxin exporter PIN-FORMED2 (PIN2) upon Pi starvation. Consistent with AUX1 and PIN2 accumulation being mediated via ethylene signaling,3 expression of 1-AMINOCYCLOPROPANE-1-CARBOXYLATE SYNTHASE 7 (ACS7) is increased at low Pi in a KAI2-dependent manner, and treatment with an ethylene precursor restores RH elongation of acs7, but not of aux1 and pin2. Thus, KAI2 signaling is increased by phosphate starvation to trigger an ethylene- AUX1/PIN2-auxin cascade required for RH elongation.
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Affiliation(s)
- José Antonio Villaécija-Aguilar
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany
| | - Caroline Körösy
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany
| | - Lukas Maisch
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany
| | - Maxime Hamon-Josse
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Andrea Petrich
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany
| | - Sonja Magosch
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany
| | - Philipp Chapman
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany
| | - Tom Bennett
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Emil Ramann Str. 4, 85354 Freising, Germany.
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25
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Yoneyama K, Brewer PB. Strigolactones, how are they synthesized to regulate plant growth and development? CURRENT OPINION IN PLANT BIOLOGY 2021; 63:102072. [PMID: 34198192 DOI: 10.1016/j.pbi.2021.102072] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 05/14/2021] [Accepted: 05/21/2021] [Indexed: 05/02/2023]
Abstract
Strigolactones (SLs) are multifunctional plant metabolites working not only as allelochemicals in the rhizosphere, but also as a novel class of hormones regulating growth and development in planta. To date, more than 30 SLs have been characterized, but the reason why plants produce structurally diverse SLs and the details of their biosynthetic pathway remain elusive. Recent studies using transcriptomics and reverse genetic techniques have paved the way to clarify the entire biosynthetic pathway of structurally diverse SLs. In this review, we discuss how various SLs are synthesized and what SL structural diversity means for plant growth and development.
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Affiliation(s)
- Kaori Yoneyama
- Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, 790-8566, Japan; PRESTO, JST, Japan.
| | - Philip B Brewer
- ARC Centre of Excellence in Plant Energy Biology, Waite Research Institute, School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond SA 5064, Australia.
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26
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Mizuno Y, Komatsu A, Shimazaki S, Naramoto S, Inoue K, Xie X, Ishizaki K, Kohchi T, Kyozuka J. Major components of the KARRIKIN INSENSITIVE2-dependent signaling pathway are conserved in the liverwort Marchantia polymorpha. THE PLANT CELL 2021; 33:2395-2411. [PMID: 33839776 PMCID: PMC8364241 DOI: 10.1093/plcell/koab106] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/06/2021] [Indexed: 05/04/2023]
Abstract
KARRIKIN INSENSITIVE2 (KAI2) was first identified as a receptor of karrikins, smoke-derived germination stimulants. KAI2 is also considered a receptor of an unidentified endogenous molecule called the KAI2 ligand. Upon KAI2 activation, signals are transmitted through the degradation of D53/SMXL proteins via MAX2-dependent ubiquitination. Although components in the KAI2-dependent signaling pathway, namely MpKAI2A and MpKAI2B, MpMAX2, and MpSMXL, exist in the genome of the liverwort Marchantia polymorpha, their functions remain unknown. Here, we show that early thallus growth is retarded and gemma dormancy in the dark is suppressed in Mpkai2a and Mpmax2 loss-of-function mutants. These defects are counteracted in Mpkai2a Mpsmxl and Mpmax2 Mpsmxl double mutants indicating that MpKAI2A, MpMAX2, and MpSMXL act in the same genetic pathway. Introduction of MpSMXLd53, in which a domain required for degradation is mutated, into wild-type plants mimicks Mpkai2a and Mpmax2 plants. In addition, the detection of citrine fluorescence in Nicotiana benthamiana cells transiently expressing a SMXL-Citrine fusion protein requires treatment with MG132, a proteasome inhibitor. These findings imply that MpSMXL is subjected to degradation, and that the degradation of MpSMXL is crucial for MpKAI2A-dependent signaling in M. polymorpha. Therefore, we claim that the basic mechanisms in the KAI2-dependent signaling pathway are conserved in M. polymorpha.
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Affiliation(s)
- Yohei Mizuno
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
| | - Aino Komatsu
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
| | - Shota Shimazaki
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
| | - Satoshi Naramoto
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
| | - Keisuke Inoue
- Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Xiaonan Xie
- Center for Bioscience Research and Education, Utsunomiya University, Tochigi 321-8505, Japan
| | - Kimitsune Ishizaki
- Graduate School of Science, Kobe University, Nada-ku, Kobe 657-8501, Japan
| | - Takayuki Kohchi
- Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Junko Kyozuka
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
- Author for correspondence:
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27
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Nelson DC. The mechanism of host-induced germination in root parasitic plants. PLANT PHYSIOLOGY 2021; 185:1353-1373. [PMID: 33793958 PMCID: PMC8133615 DOI: 10.1093/plphys/kiab043] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/25/2021] [Indexed: 05/25/2023]
Abstract
Chemical signals known as strigolactones (SLs) were discovered more than 50 years ago as host-derived germination stimulants of parasitic plants in the Orobanchaceae. Strigolactone-responsive germination is an essential adaptation of obligate parasites in this family, which depend upon a host for survival. Several species of obligate parasites, including witchweeds (Striga, Alectra spp.) and broomrapes (Orobanche, Phelipanche spp.), are highly destructive agricultural weeds that pose a significant threat to global food security. Understanding how parasites sense SLs and other host-derived stimulants will catalyze the development of innovative chemical and biological control methods. This review synthesizes the recent discoveries of strigolactone receptors in parasitic Orobanchaceae, their signaling mechanism, and key steps in their evolution.
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Affiliation(s)
- David C Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521 USA
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28
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A Raf-like kinase is required for smoke-induced seed dormancy in Arabidopsis thaliana. Proc Natl Acad Sci U S A 2021; 118:2020636118. [PMID: 33795513 DOI: 10.1073/pnas.2020636118] [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] [Indexed: 12/13/2022] Open
Abstract
Plants sense and integrate diverse stimuli to determine the timing for germination. A smoke compound, 3,4,5-trimethylfuran-2(5H)-one (trimethylbutenolide, TMB), has been identified to inhibit the seed germination of higher plants. To understand the mode of action, we examined various physiological and molecular aspects of the TMB-dependent inhibition of seed germination in Arabidopsis thaliana The results indicated that the effect of TMB is due to the enhanced physiological dormancy, which is modulated by other dormancy regulatory cues such as after-ripening, stratification, and ABA/GA signaling. In addition, gene expression profiling showed that TMB caused genome-wide transcriptional changes, altering the expression of a series of dormancy-related genes. Based on the TMB-responsive physiological contexts in Arabidopsis, we performed mutant screening to isolate genetic components that underpin the TMB-induced seed dormancy. As a result, the TMB-RESISTANT1 (TES1) gene in Arabidopsis, encoding a B2 group Raf-like kinase, was identified. Phenotypic analysis of the tes1 mutant implicated that TES1 has a critical role in the TMB-responsive gene expression and the inhibition of seed germination. Taken together, we propose that plants have been equipped with a TMB sensory pathway through which the TMB induces the seed dormancy in a TES1-dependent way.
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29
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Wang NQ, Kong CH, Wang P, Meiners SJ. Root exudate signals in plant-plant interactions. PLANT, CELL & ENVIRONMENT 2021; 44:1044-1058. [PMID: 32931018 DOI: 10.1111/pce.13892] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/31/2020] [Accepted: 09/08/2020] [Indexed: 05/12/2023]
Abstract
Plant-to-plant signalling is a key mediator of interactions among plant species. Plants can perceive and respond to chemical cues emitted from their neighbours, altering survival and performance, impacting plant coexistence and community assembly. An increasing number of studies indicate root exudates as key players in plant-to-plant signalling. Root exudates mediate root detection and behaviour, kin recognition, flowering and production, driving inter- and intra-specific facilitation in cropping systems and mixed-species plantations. Altered interactions may be attributed to the signalling components within root exudates. Root ethylene, strigolactones, jasmonic acid, (-)-loliolide and allantoin are signalling chemicals that convey information on local conditions in plant-plant interactions. These root-secreted signalling chemicals appear ubiquitous in plants and trigger a series of belowground responses inter- and intra-specifically, involving molecular events in biosynthesis, secretion and action. The secretion of root signals, mainly mediated by ATP-binding cassette transporters, is critical. Root-secreted signalling chemicals and their molecular mechanisms are rapidly revealing a multitude of fascinating plant-plant interactions. However, many root signals, particularly species-specific signals and their underlying mechanisms, remain to be uncovered due to methodological limitations and root-soil interactions. A thorough understanding of root-secreted chemical signals and their mechanisms will offer many ecological implications and potential applications for sustainable agriculture.
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Affiliation(s)
- Nan-Qi Wang
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Chui-Hua Kong
- College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
| | - Peng Wang
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Scott J Meiners
- Department of Biological Sciences, Eastern Illinois University, Charleston, Illinois, USA
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30
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31
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Carbonnel S, Torabi S, Gutjahr C. MAX2-independent transcriptional responses to rac-GR24 in Lotus japonicus roots. PLANT SIGNALING & BEHAVIOR 2021; 16:1840852. [PMID: 33126824 PMCID: PMC7781757 DOI: 10.1080/15592324.2020.1840852] [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] [Received: 09/10/2020] [Revised: 10/14/2020] [Accepted: 10/17/2020] [Indexed: 05/18/2023]
Abstract
Strigolactones (SLs) and smoke-derived Karrikins (KARs) are structurally similar butenolide compounds that control distinct aspects of plant development. They are perceived by two closely related α/β hydrolases D14 and KAI2, respectively. Responses to both molecules involve the F-box protein MAX2 that participates in the Skp1-Cullin-F-box (SCF) complex, which ubiquitylates developmental regulators of the SMXL family to mark them for degradation by the 26S proteasome, enabling SL and KAR responses. Current research on SL and KAR signaling uses the synthetic molecules rac-GR24, KAR1 and KAR2 for pharmacological treatments. In a previous microarray analysis, we observed transcriptional activation in response to rac-GR24 in Lotus japonicus seedling roots. We retested transcript accumulation of selected genes by quantitative PCR in the wild type and the max2-4 mutant, and found that surprisingly, a number of them respond to rac-GR24 in a MAX2-independent manner, and also respond in roots of d14 and kai2a kai2b double mutants. Thus, the synthetic compounds induce transcriptional responses independent of their perception by the canonical receptor complex.
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Affiliation(s)
- Samy Carbonnel
- Faculty of Biology, Biocenter Martinsried, LMU Munich, Martinsried, Germany
- TUM School of Life Science Weihenstephan, Technical University of Munich, Freising, Germany
| | - Salar Torabi
- TUM School of Life Science Weihenstephan, Technical University of Munich, Freising, Germany
| | - Caroline Gutjahr
- Faculty of Biology, Biocenter Martinsried, LMU Munich, Martinsried, Germany
- TUM School of Life Science Weihenstephan, Technical University of Munich, Freising, Germany
- CONTACT Caroline Gutjahr Plant Genetics, TUM School of Life Sciences Weihenstephan, Emil Ramann Str. 4, 85354, Freising
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32
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Villaécija-Aguilar JA, Struk S, Goormachtig S, Gutjahr C. Bioassays for the Effects of Strigolactones and Other Small Molecules on Root and Root Hair Development. Methods Mol Biol 2021; 2309:129-142. [PMID: 34028684 DOI: 10.1007/978-1-0716-1429-7_11] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Growth and development of plant roots are highly dynamic and adaptable to environmental conditions. They are under the control of several plant hormone signaling pathways, and therefore root developmental responses can be used as bioassays to study the action of plant hormones and other small molecules. In this chapter, we present different procedures to measure root traits of the model plant Arabidopsis thaliana. We explain methods for phenotypic analysis of lateral root development, primary root length, root skewing and straightness, and root hair density and length. We describe optimal growth conditions for Arabidopsis seedlings for reproducible root and root hair developmental outputs; and how to acquire images and measure the different traits using image analysis with relatively low-tech equipment. We provide guidelines for a semiautomatic image analysis of primary root length, root skewing, and root straightness in Fiji and a script to automate the calculation of root angle deviation from the vertical and root straightness. By including mutants defective in strigolactone (SL) or KAI2 ligand (KL) synthesis and/or signaling, these methods can be used as bioassays for different SLs or SL-like molecules. In addition, the techniques described here can be used for studying seedling root system architecture, root skewing, and root hair development in any context.
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Affiliation(s)
| | - Sylwia Struk
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Sofie Goormachtig
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences Weihenstephan, Technical University of Munich (TUM), Freising, Germany.
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33
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Hamiaux C, Janssen BJ, Snowden KC. The Use of Differential Scanning Fluorimetry to Assess Strigolactone Receptor Function. Methods Mol Biol 2021; 2309:233-243. [PMID: 34028691 DOI: 10.1007/978-1-0716-1429-7_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Differential scanning fluorimetry (DSF) is a method used for assessing the interaction of ligands with proteins. In most cases binding of a ligand to proteins tends to increase the melting temperature (Tm) of the protein involved. However, in the case of strigolactone receptors (e.g., D14, AtD14, DAD2, RMS3) from plants, the Tm tends to be reduced in the presence of strigolactones. This is likely due to increased flexibility of the receptors in the presence of hormone ligands.DSF experiments are simple, fast, amenable to high-throughput formats, and cost effective. They have therefore gained in popularity, including within the field of SL signaling. Typically in DSF the receptor protein is purified and incubated with the ligand (strigolactone, agonist, or antagonist) and a (fluorescent) reporter dye. The mixture is then placed in a quantitative PCR instrument and subjected to an increasing temperature gradient. Changes in fluorescence are recorded along the gradient, as the dye interacts with unfolded portions of the protein becoming accessible when the protein "melts". Differences in the temperature at which the protein unfolds in the absence and in the presence of the ligand are interpreted as indicating interactions between the ligand and the receptor.
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Affiliation(s)
- Cyril Hamiaux
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand
| | - Bart J Janssen
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand
| | - Kimberley C Snowden
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand.
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34
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Aquino B, Bradley JM, Lumba S. On the outside looking in: roles of endogenous and exogenous strigolactones. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:322-334. [PMID: 33215770 DOI: 10.1111/tpj.15087] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/27/2020] [Accepted: 10/21/2020] [Indexed: 05/15/2023]
Abstract
A collection of small molecules called strigolactones (SLs) act as both endogenous hormones to control plant development and as ecological communication cues between organisms. SL signalling overlaps with that of a class of smoke-derived compounds, karrikins (KARs), which have distinct yet overlapping developmental effects on plants. Although the roles of SLs in shoot and root development, in the promotion of arbuscular mycorrhizal (AM) fungal branching and in parasitic plant germination have been well characterized, recent data have illustrated broader roles for these compounds in the rhizosphere. Here, we review the known roles of SLs in development, growth of AM fungi and germination of parasitic plants to develop a framework for understanding the use of SLs as molecules of communication in the rhizosphere. It appears, for example, that there are many connections between SLs and phosphate utilization. Low phosphate levels regulate SL metabolism and, in turn, SLs sculpt root and shoot architecture to coordinate growth and optimize phosphate uptake from the environment. Plant-exuded SLs attract fungal symbionts to deliver inorganic phosphate (Pi) to the host. These and other examples suggest the boundary between exogenous and endogenous SL functions can be easily blurred and a more holistic view of these small molecules is likely to be required to fully understand SL biology. Related to this, we summarize and discuss evidence for a primitive role of SLs in moss as a quorum sensing-like molecule, providing a unifying concept of SLs as endogenous and exogenous signalling molecules.
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Affiliation(s)
- Bruno Aquino
- Department of Cell and Systems Biology, University of Toronto, 25 Willcocks Street, Toronto, M5S 3B2, Canada
| | - James M Bradley
- Department of Cell and Systems Biology, University of Toronto, 25 Willcocks Street, Toronto, M5S 3B2, Canada
| | - Shelley Lumba
- Department of Cell and Systems Biology, University of Toronto, 25 Willcocks Street, Toronto, M5S 3B2, Canada
- Centre for the Analysis of Genome Evolution and Function, University of Toronto, 25 Willcocks Street, Toronto, ON, M5S 3B2, Canada
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Ho-Plágaro T, Morcillo RJL, Tamayo-Navarrete MI, Huertas R, Molinero-Rosales N, López-Ráez JA, Macho AP, García-Garrido JM. DLK2 regulates arbuscule hyphal branching during arbuscular mycorrhizal symbiosis. THE NEW PHYTOLOGIST 2021; 229:548-562. [PMID: 32966595 DOI: 10.1111/nph.16938] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/02/2020] [Indexed: 06/11/2023]
Abstract
D14 and KAI2 receptors enable plants to distinguish between strigolactones (SLs) and karrikins (KARs), respectively, in order to trigger appropriate environmental and developmental responses. Both receptors are related to the regulation of arbuscular mycorrhiza (AM) formation and are members of the RsbQ-like family of α,β-hydrolases. DLK2 proteins, whose function remains unknown, constitute a third clade from the RsbQ-like protein family. We investigated whether the tomato SlDLK2 is a new regulatory component in the AM symbiosis. Genetic approaches were conducted to analyze SlDLK2 expression and to understand SlDLK2 function in AM symbiosis. We show that SlDLK2 expression in roots is AM-dependent and is associated with cells containing arbuscules. SlDLK2 ectopic expression arrests arbuscule branching and downregulates AM-responsive genes, even in the absence of symbiosis; while the opposite effect was observed upon SlDLK2 silencing. Moreover, SlDLK2 overexpression in Medicago truncatula roots showed the same altered phenotype observed in tomato roots. Interestingly, SlDLK2 interacts with DELLA, a protein that regulates arbuscule formation/degradation in AM roots. We propose that SlDLK2 is a new component of the complex plant-mediated mechanism regulating the life cycle of arbuscules in AM symbiosis.
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Affiliation(s)
- Tania Ho-Plágaro
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n◦1, Granada, 18008, Spain
| | - Rafael J L Morcillo
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - María Isabel Tamayo-Navarrete
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n◦1, Granada, 18008, Spain
| | - Raúl Huertas
- Noble Research Institute LLC, 2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - Nuria Molinero-Rosales
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n◦1, Granada, 18008, Spain
| | - Juan Antonio López-Ráez
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n◦1, Granada, 18008, Spain
| | - Alberto P Macho
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai, 201602, China
| | - José Manuel García-Garrido
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (EEZ), CSIC, Calle Profesor Albareda n◦1, Granada, 18008, Spain
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Khatoon A, Rehman SU, Aslam MM, Jamil M, Komatsu S. Plant-Derived Smoke Affects Biochemical Mechanism on Plant Growth and Seed Germination. Int J Mol Sci 2020; 21:E7760. [PMID: 33092218 PMCID: PMC7588921 DOI: 10.3390/ijms21207760] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 02/03/2023] Open
Abstract
The role of plant-derived smoke, which is changed in mineral-nutrient status, in enhancing germination and post-germination was effectively established. The majority of plant species positively respond to plant-derived smoke in the enhancement of seed germination and plant growth. The stimulatory effect of plant-derived smoke on normally growing and stressed plants may help to reduce economic and human resources, which validates its candidature as a biostimulant. Plant-derived smoke potentially facilitates the early harvest and increases crop productivity. Karrikins and cyanohydrin are the active compound in plant-derived smoke. In this review, data from the latest research explaining the effect of plant-derived smoke on morphological, physiological, biochemical, and molecular responses of plants are presented. The pathway for reception and interaction of compounds of plant-derived smoke at the cellular and molecular level of plant is described and discussed.
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Affiliation(s)
- Amana Khatoon
- Department of Botanical & Environmental Sciences, Kohat University of Science & Technology, Kohat 26000, Pakistan;
| | - Shafiq Ur Rehman
- Department of Biology, University of Haripur, Haripur 22620, Pakistan;
| | | | - Muhammad Jamil
- Department of Biotechnology & Genetic Engineering, Kohat University of Science & Technology, Kohat 26000, Pakistan;
| | - Setsuko Komatsu
- Department of Environmental and Food Sciences, Fukui University of Technology, Fukui 910-8505, Japan
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Waadt R. Phytohormone signaling mechanisms and genetic methods for their modulation and detection. CURRENT OPINION IN PLANT BIOLOGY 2020; 57:31-40. [PMID: 32622326 DOI: 10.1016/j.pbi.2020.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 05/24/2020] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
Phytohormones enable plants to regulate their development, growth and physiology according to the environmental requirements. Knowledge about the underlying signaling mechanisms, combined with the ability to pharmacologically or genetically manipulate phytohormone responses is steadily being incorporated into modern plant biology research and agriculture. This knowledge also enabled the development of genetically encoded phytohormone indicators that allow the tracking of spatiotemporal phytohormone dynamics and signaling processes in vivo. This review aims to provide an overview about core phytohormone signaling mechanisms, and about genetic tools for the manipulation and in vivo tracking of phytohormone actions.
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The karrikin signaling regulator SMAX1 controls Lotus japonicus root and root hair development by suppressing ethylene biosynthesis. Proc Natl Acad Sci U S A 2020; 117:21757-21765. [PMID: 32817510 DOI: 10.1073/pnas.2006111117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
An evolutionarily ancient plant hormone receptor complex comprising the α/β-fold hydrolase receptor KARRIKIN INSENSITIVE 2 (KAI2) and the F-box protein MORE AXILLARY GROWTH 2 (MAX2) mediates a range of developmental responses to smoke-derived butenolides called karrikins (KARs) and to yet elusive endogenous KAI2 ligands (KLs). Degradation of SUPPRESSOR OF MAX2 1 (SMAX1) after ligand perception is considered to be a key step in KAR/KL signaling. However, molecular events which regulate plant development downstream of SMAX1 removal have not been identified. Here we show that Lotus japonicus SMAX1 is specifically degraded in the presence of KAI2 and MAX2 and plays an important role in regulating root and root hair development. smax1 mutants display very short primary roots and elongated root hairs. Their root transcriptome reveals elevated ethylene responses and expression of ACC Synthase 7 (ACS7), which encodes a rate-limiting enzyme in ethylene biosynthesis. smax1 mutants release increased amounts of ethylene and their root phenotype is rescued by treatment with ethylene biosynthesis and signaling inhibitors. KAR treatment induces ACS7 expression in a KAI2-dependent manner and root developmental responses to KAR treatment depend on ethylene signaling. Furthermore, in Arabidopsis, KAR-induced root hair elongation depends on ACS7 Thus, we reveal a connection between KAR/KL and ethylene signaling in which the KAR/KL signaling module (KAI2-MAX2-SMAX1) regulates the biosynthesis of ethylene to fine-tune root and root hair development, which are important for seedling establishment at the beginning of the plant life cycle.
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Huet S, Pouvreau JB, Delage E, Delgrange S, Marais C, Bahut M, Delavault P, Simier P, Poulin L. Populations of the Parasitic Plant Phelipanche ramosa Influence Their Seed Microbiota. FRONTIERS IN PLANT SCIENCE 2020; 11:1075. [PMID: 32765559 PMCID: PMC7379870 DOI: 10.3389/fpls.2020.01075] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 06/30/2020] [Indexed: 05/27/2023]
Abstract
Seeds of the parasitic weed Phelipanche ramosa are well adapted to their hosts because they germinate and form haustorial structures to connect to roots in response to diverse host-derived molecular signals. P. ramosa presents different genetic groups that are preferentially adapted to certain hosts. Since there are indications that microbes play a role in the interaction especially in the early stages of the interaction, we studied the microbial diversity harbored by the parasitic seeds with respect to their host and genetic group. Twenty-six seed lots from seven cropping plots of three different hosts-oilseed rape, tobacco, and hemp-in the west of France were characterized for their bacterial and fungal communities using 16S rRNA gene and ITS (Internal transcribed spacer) sequences, respectively. First seeds were characterized genetically using twenty microsatellite markers and phenotyped for their sensibility to various germination stimulants including strigolactones and isothiocyanates. This led to the distinction of three P. ramosa groups that corresponded to their host of origin. The observed seed diversity was correlated to the host specialization and germination stimulant sensitivity within P. ramosa species. Microbial communities were both clustered by host and plot of origin. The seed core microbiota was composed of seventeen species that were also retrieved from soil and was in lower abundances for bacteria and similar abundances for fungi compared to seeds. The host-related core microbiota of parasitic seeds was limited and presumably well adapted to the interaction with its hosts. Two microbial candidates of Sphingobacterium species and Leptosphaeria maculans were especially identified in seeds from oilseed rape plots, suggesting their involvement in host recognition and specialization as well as seed fitness for P. ramosa by improving the production of isothiocyanates from glucosinolates in the rhizosphere of oilseed rape.
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Affiliation(s)
- Sarah Huet
- Laboratoire de Biologie et Pathologie Végétales, EA 1157, SFR 4207 QUASAV, UFR Sciences et Techniques, Université de Nantes, Nantes, France
| | - Jean-Bernard Pouvreau
- Laboratoire de Biologie et Pathologie Végétales, EA 1157, SFR 4207 QUASAV, UFR Sciences et Techniques, Université de Nantes, Nantes, France
| | - Erwan Delage
- Laboratoire des Sciences du Numérique de Nantes, UMR CNRS 6004, IMT Atlantique, ECN, Université de Nantes, Nantes, France
| | - Sabine Delgrange
- Laboratoire de Biologie et Pathologie Végétales, EA 1157, SFR 4207 QUASAV, UFR Sciences et Techniques, Université de Nantes, Nantes, France
| | - Coralie Marais
- Plateau Technique Mutualisé ANAN, SFR 4207 QUASAV, Beaucouzé, France
| | - Muriel Bahut
- Plateau Technique Mutualisé ANAN, SFR 4207 QUASAV, Beaucouzé, France
| | - Philippe Delavault
- Laboratoire de Biologie et Pathologie Végétales, EA 1157, SFR 4207 QUASAV, UFR Sciences et Techniques, Université de Nantes, Nantes, France
| | - Philippe Simier
- Laboratoire de Biologie et Pathologie Végétales, EA 1157, SFR 4207 QUASAV, UFR Sciences et Techniques, Université de Nantes, Nantes, France
| | - Lucie Poulin
- Laboratoire de Biologie et Pathologie Végétales, EA 1157, SFR 4207 QUASAV, UFR Sciences et Techniques, Université de Nantes, Nantes, France
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Wheeldon CD, Bennett T. There and back again: An evolutionary perspective on long-distance coordination of plant growth and development. Semin Cell Dev Biol 2020; 109:55-67. [PMID: 32576500 DOI: 10.1016/j.semcdb.2020.06.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 12/17/2022]
Abstract
Vascular plants, unlike bryophytes, have a strong root-shoot dichotomy in which the tissue systems are mutually interdependent; roots are completely dependent on shoots for photosynthetic sugars, and shoots are completely dependent on roots for water and mineral nutrients. Long-distance communication between shoot and root is therefore critical for the growth, development and survival of vascular plants, especially with regard to variable environmental conditions. However, this long-distance signalling does not appear an ancestral feature of land plants, and has likely arisen in vascular plants to service the radical alterations in body-plan seen in this taxon. In this review, we examine the defined hormonal root-to-shoot and shoot-to-root signalling pathways that coordinate the growth of vascular plants, with a particular view to understanding how these pathways may have evolved. We highlight the completely divergent roles of isopentenyl-adenine and trans-zeatin cytokinin species in long-distance signalling, and ask whether cytokinin can really be considered as a single class of hormones in the light of recent research. We also discuss the puzzlingly sparse evidence for auxin as a shoot-to-root signal, the evolutionary re-purposing of strigolactones and gibberellins as hormonal signals, and speculate on the possible role of sugars as long-distance signals. We conclude by discussing the 'design principles' of long-distance signalling in vascular plants.
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Affiliation(s)
- Cara D Wheeldon
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Tom Bennett
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
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41
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Spring O, Schmauder K, Lackus ND, Schreiner J, Meier C, Wellhausen J, Smith LV, Frey M. Spatial and developmental synthesis of endogenous sesquiterpene lactones supports function in growth regulation of sunflower. PLANTA 2020; 252:2. [PMID: 32504343 PMCID: PMC7275010 DOI: 10.1007/s00425-020-03409-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 05/29/2020] [Indexed: 05/28/2023]
Abstract
Tissue-specific occurrence and formation of endogenous sesquiterpene lactones has been assessed and suggests physiological function as antagonists of auxin-induced plant growth in sunflower. Sunflower, Helianthus annuus, accumulate high concentrations of bioactive sesquiterpene lactones (STL) in glandular trichomes, but in addition, structurally different STL occur in only trace amounts in the inner tissues. The spatial and temporal production of these endogenous STL during early phases of plant development is widely unknown and their physiological function as putative natural growth regulators is yet speculative. By means of HPLC and MS analysis it was shown that costunolide, dehydrocostuslactone, 8-epixanthatin and tomentosin are already present in dry seeds and can be extracted in low amounts from cotyledons, hypocotyls and roots of seedlings during the first days after germination. Semi-quantitative and RT-qPCR experiments with genes of the key enzymes of two independent routes of the endogenous STL biosynthesis confirmed the early and individual expression in these organs and revealed a gradual down regulation during the first 72-96 h after germination. Light irradiation of the plants led to a fast, but transient increase of STL in parts of the hypocotyl which correlated with growth retardation of the stem. One-sided external application of costunolide on hypocotyls conferred reduced growth of the treated side, thus resulting in the curving of the stem towards the side of the application. This indicates the inhibiting effects of STL on plant growth. The putative function of endogenous STL in sunflower as antagonists of auxin in growth processes is discussed.
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Affiliation(s)
- Otmar Spring
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany.
| | - Katharina Schmauder
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
| | - Nathalie D Lackus
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
| | - Jasmin Schreiner
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
| | - Carolin Meier
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
| | - Jan Wellhausen
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
| | - Lisa V Smith
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
| | - Maximilian Frey
- Institute of Biology, University of Hohenheim, Garbenstraße 30, 70593, Stuttgart, Germany
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42
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Hu J, Sun S, Wang X. Regulation of Shoot Branching by Strigolactones and Brassinosteroids: Conserved and Specific Functions of Arabidopsis BES1 and Rice BZR1. MOLECULAR PLANT 2020; 13:808-810. [PMID: 32222484 DOI: 10.1016/j.molp.2020.03.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 03/17/2020] [Accepted: 03/20/2020] [Indexed: 05/21/2023]
Affiliation(s)
- Jie Hu
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng 475001, China
| | - Shiyong Sun
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng 475001, China.
| | - Xuelu Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, Henan University, Kaifeng 475001, China.
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43
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Yoneyama K. Recent progress in the chemistry and biochemistry of strigolactones. JOURNAL OF PESTICIDE SCIENCE 2020; 45:45-53. [PMID: 32508512 PMCID: PMC7251197 DOI: 10.1584/jpestics.d19-084] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Strigolactones (SLs) are plant secondary metabolites derived from carotenoids. SLs play important roles in the regulation of plant growth and development in planta and coordinate interactions between plants and other organisms including root parasitic plants, and symbiotic and pathogenic microbes in the rhizosphere. In the 50 years since the discovery of the first SL, strigol, our knowledge about the chemistry and biochemistry of SLs has advanced explosively, especially over the last two decades. In this review, recent advances in the chemistry and biology of SLs are summarized and possible future outcomes are discussed.
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Affiliation(s)
- Koichi Yoneyama
- Women’s Future Development Center, Ehime University, 3 Bunkyo-cho, Matsuyama 790–8577, Japan
- To whom correspondence should be addressed. E-mail:
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44
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Vissenberg K, Claeijs N, Balcerowicz D, Schoenaers S. Hormonal regulation of root hair growth and responses to the environment in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:2412-2427. [PMID: 31993645 PMCID: PMC7178432 DOI: 10.1093/jxb/eraa048] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 01/23/2020] [Indexed: 05/04/2023]
Abstract
The main functions of plant roots are water and nutrient uptake, soil anchorage, and interaction with soil-living biota. Root hairs, single cell tubular extensions of root epidermal cells, facilitate or enhance these functions by drastically enlarging the absorptive surface. Root hair development is constantly adapted to changes in the root's surroundings, allowing for optimization of root functionality in heterogeneous soil environments. The underlying molecular pathway is the result of a complex interplay between position-dependent signalling and feedback loops. Phytohormone signalling interconnects this root hair signalling cascade with biotic and abiotic changes in the rhizosphere, enabling dynamic hormone-driven changes in root hair growth, density, length, and morphology. This review critically discusses the influence of the major plant hormones on root hair development, and how changes in rhizosphere properties impact on the latter.
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Affiliation(s)
- Kris Vissenberg
- Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, Antwerp, Belgium
- Plant Biochemistry and Biotechnology Lab, Department of Agriculture, Hellenic Mediterranean University, Stavromenos PC, Heraklion, Crete, Greece
| | - Naomi Claeijs
- Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Daria Balcerowicz
- Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, Antwerp, Belgium
| | - Sébastjen Schoenaers
- Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, Antwerp, Belgium
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45
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Bürger M, Chory J. The Many Models of Strigolactone Signaling. TRENDS IN PLANT SCIENCE 2020; 25:395-405. [PMID: 31948791 PMCID: PMC7184880 DOI: 10.1016/j.tplants.2019.12.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/23/2019] [Accepted: 12/09/2019] [Indexed: 05/20/2023]
Abstract
Strigolactones (SLs) are a class of plant hormones involved in several biological processes that are of great agricultural concern. While initiating plant-fungal symbiosis, SLs also trigger germination of parasitic plants that pose a major threat to farming. In vascular plants, SLs control shoot branching, which is linked to crop yield. SL research has been a fascinating field that has produced a variety of different signaling models, reflecting a complex picture of hormone perception. Here, we review recent developments in the SL field and the crystal structures that gave rise to various models of receptor activation. We also highlight the increasing number of discovered SL molecules, reflecting the existence of cross-kingdom SL communication.
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Affiliation(s)
- Marco Bürger
- Plant Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | - Joanne Chory
- Howard Hughes Medical Institute, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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46
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Lee HW, Sharma P, Janssen BJ, Drummond RSM, Luo Z, Hamiaux C, Collier T, Allison JR, Newcomb RD, Snowden KC. Flexibility of the petunia strigolactone receptor DAD2 promotes its interaction with signaling partners. J Biol Chem 2020; 295:4181-4193. [PMID: 32071083 PMCID: PMC7105320 DOI: 10.1074/jbc.ra119.011509] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/13/2020] [Indexed: 11/06/2022] Open
Abstract
Strigolactones (SLs) are terpenoid-derived plant hormones that regulate various developmental processes, particularly shoot branching, root development, and leaf senescence. The SL receptor has an unusual mode of action. Upon binding SL, it hydrolyzes the hormone, and then covalently binds one of the hydrolytic products. These initial events enable the SL receptor DAD2 (in petunia) to interact with the F-box protein PhMAX2A of the Skp-Cullin-F-box (SCF) complex and/or a repressor of SL signaling, PhD53A. However, it remains unclear how binding and hydrolysis structurally alters the SL receptor to enable its engagement with signaling partners. Here, we used mutagenesis to alter DAD2 and affect SL hydrolysis or DAD2's ability to interact with its signaling partners. We identified three DAD2 variants whose hydrolytic activity had been separated from the receptor's interactions with PhMAX2A or PhD53A. Two variants, DAD2N242I and DAD2F135A, having substitutions in the core α/β hydrolase-fold domain and the hairpin, exhibited hormone-independent interactions with PhMAX2A and PhD53A, respectively. Conversely, the DAD2D166A variant could not interact with PhMAX2A in the presence of SL, but its interaction with PhD53A remained unaffected. Structural analyses of DAD2N242I and DAD2D166A revealed only small differences compared with the structure of the WT receptor. Results of molecular dynamics simulations of the DAD2N242I structure suggested that increased flexibility is a likely cause for its SL-independent interaction with PhMAX2A. Our results suggest that PhMAX2A and PhD53A have distinct binding sites on the SL receptor and that its flexibility is a major determinant of its interactions with these two downstream regulators.
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Affiliation(s)
- Hui Wen Lee
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand; School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Prachi Sharma
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand; School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Bart J Janssen
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand
| | - Revel S M Drummond
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand
| | - Zhiwei Luo
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand
| | - Cyril Hamiaux
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand
| | - Thomas Collier
- School of Natural and Computational Sciences, Massey University Albany, Auckland, New Zealand
| | - Jane R Allison
- School of Biological Sciences, University of Auckland, Auckland, New Zealand; Digital Life Institute & Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand; Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
| | - Richard D Newcomb
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand; School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Kimberley C Snowden
- The New Zealand Institute for Plant & Food Research Limited, Auckland, New Zealand.
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47
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Yang T, Lian Y, Wang C. Comparing and Contrasting the Multiple Roles of Butenolide Plant Growth Regulators: Strigolactones and Karrikins in Plant Development and Adaptation to Abiotic Stresses. Int J Mol Sci 2019; 20:ijms20246270. [PMID: 31842355 PMCID: PMC6941112 DOI: 10.3390/ijms20246270] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 12/10/2019] [Accepted: 12/10/2019] [Indexed: 02/07/2023] Open
Abstract
Strigolactones (SLs) and karrikins (KARs) are both butenolide molecules that play essential roles in plant growth and development. SLs are phytohormones, with SLs having known functions within the plant they are produced in, while KARs are found in smoke emitted from burning plant matter and affect seeds and seedlings in areas of wildfire. It has been suggested that SL and KAR signaling may share similar mechanisms. The α/β hydrolases DWARF14 (D14) and KARRIKIN INSENSITIVE 2 (KAI2), which act as receptors of SL and KAR, respectively, both interact with the F-box protein MORE AXILLARY GROWTH 2 (MAX2) in order to target SUPPRESSOR OF MAX2 1 (SMAX1)-LIKE/D53 family members for degradation via the 26S proteasome. Recent reports suggest that SLs and/or KARs are also involved in regulating plant responses and adaptation to various abiotic stresses, particularly nutrient deficiency, drought, salinity, and chilling. There is also crosstalk with other hormone signaling pathways, including auxin, gibberellic acid (GA), abscisic acid (ABA), cytokinin (CK), and ethylene (ET), under normal and abiotic stress conditions. This review briefly covers the biosynthetic and signaling pathways of SLs and KARs, compares their functions in plant growth and development, and reviews the effects of any crosstalk between SLs or KARs and other plant hormones at various stages of plant development. We also focus on the distinct responses, adaptations, and regulatory mechanisms related to SLs and/or KARs in response to various abiotic stresses. The review closes with discussion on ways to gain additional insights into the SL and KAR pathways and the crosstalk between these related phytohormones.
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Affiliation(s)
| | | | - Chongying Wang
- Correspondence: ; Tel.: +86-0931-8914155; Fax: +86-0931-8914155
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