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Chang W, Qiao Q, Li Q, Li X, Li Y, Huang X, Wang Y, Li J, Wang B, Wang L. Non-transcriptional regulatory activity of SMAX1 and SMXL2 mediates karrikin-regulated seedling response to red light in Arabidopsis. MOLECULAR PLANT 2024; 17:1054-1072. [PMID: 38807366 DOI: 10.1016/j.molp.2024.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 04/09/2024] [Accepted: 05/26/2024] [Indexed: 05/30/2024]
Abstract
Karrikins and strigolactones govern plant development and environmental responses through closely related signaling pathways. The transcriptional repressor proteins SUPPRESSOR OF MAX2 1 (SMAX1), SMAX1-like2 (SMXL2), and D53-like SMXLs mediate karrikin and strigolactone signaling by directly binding downstream genes or by inhibiting the activities of transcription factors. In this study, we characterized the non-transcriptional regulatory activities of SMXL proteins in Arabidopsis. We discovered that SMAX1 and SMXL2 with mutations in their ethylene-response factor-associated amphiphilic repression (EAR) motif had undetectable or weak transcriptional repression activities but still partially rescued the hypocotyl elongation defects and fully reversed the cotyledon epinasty defects of the smax1 smxl2 mutant. SMAX1 and SMXL2 directly interact with PHYTOCHROME INTERACTION FACTOR 4 (PIF4) and PIF5 to enhance their protein stability by interacting with phytochrome B (phyB) and suppressing the association of phyB with PIF4 and PIF5. The karrikin-responsive genes were then identified by treatment with GR24ent-5DS, a GR24 analog showing karrikin activity. Interestingly, INDOLE-3-ACETIC ACID INDUCIBLE 29 (IAA29) expression was repressed by GR24ent-5DS treatment in a PIF4- and PIF5-dependent and EAR-independent manner, whereas KARRIKIN UPREGULATED F-BOX 1 (KUF1) expression was induced in a PIF4- and PIF5-independent and EAR-dependent manner. Furthermore, the non-transcriptional regulatory activity of SMAX1, which is independent of the EAR motif, had a global effect on gene expression. Taken together, these results indicate that non-transcriptional regulatory activities of SMAX1 and SMXL2 mediate karrikin-regulated seedling response to red light.
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Affiliation(s)
- Wenwen Chang
- Key Laboratory of Seed Innovation, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiao Qiao
- Key Laboratory of Seed Innovation, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingtian Li
- Yazhouwan National Laboratory, Sanya, Hainan 572024, China
| | - Xin Li
- Key Laboratory of Seed Innovation, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanyan Li
- Key Laboratory of Seed Innovation, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, China
| | - Xiahe Huang
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Yingchun Wang
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiayang Li
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; Yazhouwan National Laboratory, Sanya, Hainan 572024, China
| | - Bing Wang
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Lei Wang
- Key Laboratory of Seed Innovation, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, Hebei 050021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Porat A, Tekinalp A, Bhosale Y, Gazzola M, Meroz Y. On the mechanical origins of waving, coiling and skewing in Arabidopsis thaliana roots. Proc Natl Acad Sci U S A 2024; 121:e2312761121. [PMID: 38446852 PMCID: PMC10945788 DOI: 10.1073/pnas.2312761121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 12/07/2023] [Indexed: 03/08/2024] Open
Abstract
By masterfully balancing directed growth and passive mechanics, plant roots are remarkably capable of navigating complex heterogeneous environments to find resources. Here, we present a theoretical and numerical framework which allows us to interrogate and simulate the mechanical impact of solid interfaces on the growth pattern of plant organs. We focus on the well-known waving, coiling, and skewing patterns exhibited by roots of Arabidopsis thaliana when grown on inclined surfaces, serving as a minimal model of the intricate interplay with solid substrates. By modeling growing slender organs as Cosserat rods that mechanically interact with the environment, our simulations verify hypotheses of waving and coiling arising from the combination of active gravitropism and passive root-plane responses. Skewing is instead related to intrinsic twist due to cell file rotation. Numerical investigations are outfitted with an analytical framework that consistently relates transitions between straight, waving, coiling, and skewing patterns with substrate tilt angle. Simulations are found to corroborate theory and recapitulate a host of reported experimental observations, thus providing a systematic approach for studying in silico plant organs behavior in relation to their environment.
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Affiliation(s)
- Amir Porat
- Department of Condensed Matter, School of Physics and Astronomy, Tel Aviv University, Tel Aviv69978, Israel
- Center for Physics, Chemistry of Living Systems, Tel-Aviv University, Tel Aviv69978, Israel
| | - Arman Tekinalp
- Mechanical Sciences and Engineering, University of Illinois at Urbana–Champaign, Urbana, IL61801
| | - Yashraj Bhosale
- Mechanical Sciences and Engineering, University of Illinois at Urbana–Champaign, Urbana, IL61801
| | - Mattia Gazzola
- Mechanical Sciences and Engineering, University of Illinois at Urbana–Champaign, Urbana, IL61801
| | - Yasmine Meroz
- Center for Physics, Chemistry of Living Systems, Tel-Aviv University, Tel Aviv69978, Israel
- Faculty of Life Sciences, School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
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Kamran M, Melville KT, Waters MT. Karrikin signalling: impacts on plant development and abiotic stress tolerance. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1174-1186. [PMID: 38001035 PMCID: PMC10860534 DOI: 10.1093/jxb/erad476] [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: 07/28/2023] [Accepted: 11/23/2023] [Indexed: 11/26/2023]
Abstract
Plants rely upon a diverse range of metabolites to control growth and development, and to overcome stress that results from suboptimal conditions. Karrikins (KARs) are a class of butenolide compounds found in smoke that stimulate seed germination and regulate various developmental processes in plants. KARs are perceived via a plant α/β-hydrolase called KARRIKIN INSENSITIVE2 (KAI2), which also functions as a receptor for a postulated phytohormone, provisionally termed KAI2 ligand (KL). Considered natural analogues of KL, KARs have been extensively studied for their effects on plant growth and their crosstalk with plant hormones. The perception and response pathway for KAR-KL signalling is closely related to that of strigolactones, another class of butenolides with numerous functions in regulating plant growth. KAR-KL signalling influences seed germination, seedling photomorphogenesis, root system architecture, abiotic stress responses, and arbuscular mycorrhizal symbiosis. Here, we summarize current knowledge of KAR-KL signalling, focusing on its role in plant development, its effects on stress tolerance, and its interaction with other signalling mechanisms.
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Affiliation(s)
- Muhammad Kamran
- School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia
| | - Kim T Melville
- School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia
| | - Mark T Waters
- School of Molecular Sciences, The University of Western Australia, Perth, WA 6009, Australia
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Fang P, Li M, Guo Q, Wu X, Hu Y, Cheng Y, Xu P. Genome-wide analysis of the SMXL gene family in common bean and identification of karrikin-responsive PvSMXL2 as a negative regulator of PEG-induced drought stress. Gene 2023; 887:147741. [PMID: 37634881 DOI: 10.1016/j.gene.2023.147741] [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] [Received: 06/19/2023] [Revised: 08/05/2023] [Accepted: 08/24/2023] [Indexed: 08/29/2023]
Abstract
Common bean (Phaseolus vulgaris L.) is a major legume crop worldwide, but its growth and development frequently face challenges due to abiotic stresses, particularly drought. Proper supplement of copper could mitigate the adverse effects of drought, but excessive accumulation of this metal in plants can be harmful. The suppressor of MAX2 1-like (SMXL) gene family, which plays important roles in various plant processes, including stress responses, remains poorly understood in common bean. In this study, we identified nine orthologues of SMXL genes in common bean, which are located on six chromosomes and classified into four subgroups. Basic molecular properties, including theoretical isoelectric point (PI), molecular weight (MW), grand average of hydropathicity (GVIO), gene structure, and conserved motifs were characterized, and numerous cis-elements in promoters were predicted. The expression patterns of PvSMXL genes were found to be distinct under 10% polyethylene glycol (PEG)-induced drought stress and 200 μM Cu treatments. Most PvSMXLs showed reduced expression in response to Cu treatment, whereas nearly half PvSMXLs exhibited inducible expression under drought stress. PvSMXL2, which exhibited a rapid response to karrikin 1 (KAR1), an active form of the plant growth regulators newly found in the smoke of burning plant material, was down-regulated by both PEG-induced drought and Cu stresses. Transient silencing of PvSMXL2 resulted in enhanced drought stress tolerance without conferring Cu tolerance. These findings provide valuable insights into the functions of SMXL genes in common bean under abiotic stress conditions.
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Affiliation(s)
- Pingping Fang
- Key Laboratory of Specialty Agri-Product Quality and Hazard Controlling Technology of Zhejiang, College of Life Sciences, China Jiliang University, Hangzhou 310018, PR China
| | - Minxuan Li
- Key Laboratory of Specialty Agri-Product Quality and Hazard Controlling Technology of Zhejiang, College of Life Sciences, China Jiliang University, Hangzhou 310018, PR China
| | - Qinwei Guo
- Quzhou Key Laboratory for Germplasm Innovation and Utilization of Crop, Institute of Vegetables, Quzhou Academy of Agricultural and Forestry Sciences, Quzhou 324000, PR China
| | - Xinyang Wu
- Key Laboratory of Specialty Agri-Product Quality and Hazard Controlling Technology of Zhejiang, College of Life Sciences, China Jiliang University, Hangzhou 310018, PR China
| | - Yannan Hu
- Key Laboratory of Specialty Agri-Product Quality and Hazard Controlling Technology of Zhejiang, College of Life Sciences, China Jiliang University, Hangzhou 310018, PR China
| | - Yusu Cheng
- Key Laboratory of Specialty Agri-Product Quality and Hazard Controlling Technology of Zhejiang, College of Life Sciences, China Jiliang University, Hangzhou 310018, PR China
| | - Pei Xu
- Key Laboratory of Specialty Agri-Product Quality and Hazard Controlling Technology of Zhejiang, College of Life Sciences, China Jiliang University, Hangzhou 310018, PR China.
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Varshney K, Gutjahr C. KAI2 Can Do: Karrikin Receptor Function in Plant Development and Response to Abiotic and Biotic Factors. PLANT & CELL PHYSIOLOGY 2023; 64:984-995. [PMID: 37548562 PMCID: PMC10504578 DOI: 10.1093/pcp/pcad077] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/02/2023] [Accepted: 07/14/2023] [Indexed: 08/08/2023]
Abstract
The α/β hydrolase KARRIKIN INSENSITIVE 2 (KAI2) functions as a receptor for a yet undiscovered phytohormone, provisionally termed KAI2 ligand (KL). In addition, it perceives karrikin, a butenolide compound found in the smoke of burnt plant material. KAI2-mediated signaling is involved in regulating seed germination and in shaping seedling and adult plant morphology, both above and below ground. It also governs responses to various abiotic stimuli and stresses and shapes biotic interactions. KAI2-mediated signaling is being linked to an elaborate cross-talk with other phytohormone pathways such as auxin, gibberellin, abscisic acid, ethylene and salicylic acid signaling, in addition to light and nutrient starvation signaling. Further connections will likely be revealed in the future. This article summarizes recent advances in unraveling the function of KAI2-mediated signaling and its interaction with other signaling pathways.
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Affiliation(s)
- Kartikye Varshney
- Department of Root Biology and Symbiosis, Max Planck Institute of Molecular Plant Physiology, Potsdam Science Park, Am Mühlenberg 1, Potsdam-Golm 14476, Germany
| | - Caroline Gutjahr
- Department of Root Biology and Symbiosis, Max Planck Institute of Molecular Plant Physiology, Potsdam Science Park, Am Mühlenberg 1, Potsdam-Golm 14476, Germany
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Huizinga S, Bouwmeester HJ. Role of Strigolactones in the Host Specificity of Broomrapes and Witchweeds. PLANT & CELL PHYSIOLOGY 2023; 64:936-954. [PMID: 37319019 PMCID: PMC10504575 DOI: 10.1093/pcp/pcad058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/05/2023] [Accepted: 06/14/2023] [Indexed: 06/17/2023]
Abstract
Root parasitic plants of the Orobanchaceae, broomrapes and witchweeds, pose a severe problem to agriculture in Europe, Asia and especially Africa. These parasites are totally dependent on their host for survival, and therefore, their germination is tightly regulated by host presence. Indeed, their seeds remain dormant in the soil until a host root is detected through compounds called germination stimulants. Strigolactones (SLs) are the most important class of germination stimulants. They play an important role in planta as a phytohormone and, upon exudation from the root, function in the recruitment of symbiotic arbuscular mycorrhizal fungi. Plants exude mixtures of various different SLs, possibly to evade detection by these parasites and still recruit symbionts. Vice versa, parasitic plants must only respond to the SL composition that is exuded by their host, or else risk germination in the presence of non-hosts. Therefore, parasitic plants have evolved an entire clade of SL receptors, called HTL/KAI2s, to perceive the SL cues. It has been demonstrated that these receptors each have a distinct sensitivity and specificity to the different known SLs, which possibly allows them to recognize the SL-blend characteristic of their host. In this review, we will discuss the molecular basis of SL sensitivity and specificity in these parasitic plants through HTL/KAI2s and review the evidence that these receptors contribute to host specificity of parasitic plants.
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Affiliation(s)
- Sjors Huizinga
- Plant Hormone Biology Group, Green Life Sciences Cluster, Swammerdam Institute for Life Science, University of Amsterdam, Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Harro J Bouwmeester
- Plant Hormone Biology Group, Green Life Sciences Cluster, Swammerdam Institute for Life Science, University of Amsterdam, Science Park 904, Amsterdam 1098 XH, The Netherlands
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7
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Tal L, Guercio AM, Varshney K, Young A, Gutjahr C, Shabek N. C-terminal conformational changes in SCF-D3/MAX2 ubiquitin ligase are required for KAI2-mediated signaling. THE NEW PHYTOLOGIST 2023; 239:2067-2075. [PMID: 37376727 DOI: 10.1111/nph.19101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023]
Affiliation(s)
- Lior Tal
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, 95616, USA
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Angelica M Guercio
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, 95616, USA
| | - Kartikye Varshney
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), 85354, Freising, Germany
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam Science Park, 14476, Potsdam-Golm, Germany
| | - Aleczander Young
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, 95616, USA
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), 85354, Freising, Germany
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam Science Park, 14476, Potsdam-Golm, Germany
| | - Nitzan Shabek
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, 95616, USA
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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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Ibrahim S, Ahmad N, Kuang L, Li K, Tian Z, Sadau SB, Tajo SM, Wang X, Wang H, Dun X. Transcriptome analysis reveals key regulatory genes for root growth related to potassium utilization efficiency in rapeseed ( Brassica napus L.). FRONTIERS IN PLANT SCIENCE 2023; 14:1194914. [PMID: 37546248 PMCID: PMC10400329 DOI: 10.3389/fpls.2023.1194914] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 07/03/2023] [Indexed: 08/08/2023]
Abstract
Root system architecture (RSA) is the primary predictor of nutrient intake and significantly influences potassium utilization efficiency (KUE). Uncertainty persists regarding the genetic factors governing root growth in rapeseed. The root transcriptome analysis reveals the genetic basis driving crop root growth. In this study, RNA-seq was used to profile the overall transcriptome in the root tissue of 20 Brassica napus accessions with high and low KUE. 71,437 genes in the roots displayed variable expression profiles between the two contrasting genotype groups. The 212 genes that had varied expression levels between the high and low KUE lines were found using a pairwise comparison approach. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional classification analysis revealed that the DEGs implicated in hormone and signaling pathways, as well as glucose, lipid, and amino acid metabolism, were all differently regulated in the rapeseed root system. Additionally, we discovered 33 transcription factors (TFs) that control root development were differentially expressed. By combining differential expression analysis, weighted gene co-expression network analysis (WGCNA), and recent genome-wide association study (GWAS) results, four candidate genes were identified as essential hub genes. These potential genes were located fewer than 100 kb from the peak SNPs of QTL clusters, and it was hypothesized that they regulated the formation of the root system. Three of the four hub genes' homologs-BnaC04G0560400ZS, BnaC04G0560400ZS, and BnaA03G0073500ZS-have been shown to control root development in earlier research. The information produced by our transcriptome profiling could be useful in revealing the molecular processes involved in the growth of rapeseed roots in response to KUE.
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Affiliation(s)
- Sani Ibrahim
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
- Department of Plant Biology, Faculty of Life Sciences, College of Natural and Pharmaceutical Sciences, Bayero University, Kano, Nigeria
| | - Nazir Ahmad
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Lieqiong Kuang
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Keqi Li
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Ze Tian
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Salisu Bello Sadau
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences (Institute of Cotton Research (ICR), CAAS), Anyang, China
| | - Sani Muhammad Tajo
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences (Institute of Cotton Research (ICR), CAAS), Anyang, China
| | - Xinfa Wang
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Hanzhong Wang
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Xiaoling Dun
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
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Liu M, Shan Q, Ding E, Gu T, Gong B. Karrikin increases tomato cold tolerance via strigolactone and the abscisic acid signaling network. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 332:111720. [PMID: 37120034 DOI: 10.1016/j.plantsci.2023.111720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 04/23/2023] [Accepted: 04/25/2023] [Indexed: 05/05/2023]
Abstract
As a class of biostimulants, karrikins (KARs) were first identified from plant-derived smoke to regulate plant growth, development, and stress tolerance. However, the roles of KARs in plant cold tolerance and their crosstalk with strigolactones (SLs) and abscisic acid (ABA) remain elusive. We studied the interaction among KAR, SLs, and ABA in cold acclimatization with KAI2-, MAX1-, SnRK2.5-silenced, or cosilenced plant materials. KAI2 is involved in smoke-water- (SW-) and KAR-mediated cold tolerance. MAX1 acts downstream of KAR in cold acclimation. ABA biosynthesis and sensitivity are regulated by KAR and SLs, which improve cold acclimation through the SnRK2.5 component. The physiological mechanisms of SW and KAR in improving growth, yield, and tolerance under a long-term sublow temperature environment were also studied. SW and KAR were shown to improve tomato growth and yield under sublow temperature conditions by regulating nutritional uptake, leaf temperature control, photosynthetic defense, ROS scavenging, and CBF transcriptional activation. Together, SW, which functions via the KAR-mediated SL and ABA signaling network, has potential application value for increasing cold tolerance in tomato production.
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Affiliation(s)
- Minghui Liu
- State Key Laboratory of Crop Biology / College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an 271018, China
| | - Qing Shan
- State Key Laboratory of Crop Biology / College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an 271018, China
| | - Erqiao Ding
- State Key Laboratory of Crop Biology / College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an 271018, China
| | - Tingting Gu
- College of Agricultural Sciences and Technology, Shandong Agriculture and Engineering University, Ji'nan 250100, China
| | - Biao Gong
- State Key Laboratory of Crop Biology / College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an 271018, China.
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11
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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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12
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Zheng X, Liu F, Yang X, Li W, Chen S, Yue X, Jia Q, Sun X. The MAX2-KAI2 module promotes salicylic acid-mediated immune responses in Arabidopsis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023. [PMID: 36738234 DOI: 10.1111/jipb.13463] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Arabidopsis MORE AXILLARY GROWTH2 (MAX2) is a key component in the strigolactone (SL) and karrikin (KAR) signaling pathways and regulates the degradation of SUPPRESSOR OF MAX2 1/SMAX1-like (SMAX1/SMXL) proteins, which are transcriptional co-repressors that regulate plant architecture, as well as abiotic and biotic stress responses. The max2 mutation reduces resistance against Pseudomonas syringae pv. tomato (Pst). To uncover the mechanism of MAX2-mediated resistance, we evaluated the resistance of various SL and KAR signaling pathway mutants. The resistance of SL-deficient mutants and of dwarf 14 (d14) was similar to that of the wild-type, whereas the resistance of the karrikin insensitive 2 (kai2) mutant was compromised, demonstrating that the KAR signaling pathway, not the SL signaling pathway, positively regulates the immune response. We measured the resistance of smax1 and smxl mutants, as well as the double, triple, and quadruple mutants with max2, which revealed that both the smax1 mutant and smxl6/7/8 triple mutant rescue the low resistance phenotype of max2 and that SMAX1 accumulation diminishes resistance. The susceptibility of smax1D, containing a degradation-insensitive form of SMAX1, further confirmed the SMAX1 function in the resistance. The relationship between the accumulation of SMAX1/SMXLs and disease resistance suggested that the inhibitory activity of SMAX1 to resistance requires SMXL6/7/8. Moreover, the exogenous application of KAR2 enhanced resistance against Pst, but KAR-induced resistance depended on salicylic acid (SA) signaling. Inhibition of karrikin signaling delayed SA-mediated defense responses and inhibited pathogen-induced protein biosynthesis. Together, we propose that the MAX2-KAI2-SMAX1 complex regulates resistance with the assistance of SMXL6/7/8 and SA signaling and that SMAX1/SMXLs possibly form a multimeric complex with their target transcription factors to fine tune immune responses.
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Affiliation(s)
- Xiujuan Zheng
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
| | - Fangqian Liu
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
| | - Xianfeng Yang
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
| | - Weiqiang Li
- Jilin Da'an Agro-ecosystem National Observation Research Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Sique Chen
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
| | - Xinwu Yue
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
| | - Qi Jia
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
| | - Xinli Sun
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture & Forestry University, Fuzhou, 350002, China
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13
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Abdelrahman M, Mostofa MG, Tran CD, El-Sayed M, Li W, Sulieman S, Tanaka M, Seki M, Tran LSP. The Karrikin Receptor Karrikin Insensitive2 Positively Regulates Heat Stress Tolerance in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2023; 63:1914-1926. [PMID: 35880749 DOI: 10.1093/pcp/pcac112] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 06/23/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
In this study, we investigated the potential role of the karrikin receptor KARRIKIN INSENSITIVE2 (KAI2) in the response of Arabidopsis seedlings to high-temperature stress. We performed phenotypic, physiological and transcriptome analyses of Arabidopsis kai2 mutants and wild-type (WT) plants under control (kai2_C and WT_C, respectively) and 6- and 24-h heat stress conditions (kai2_H6, kai2_H24, WT_H6 and WT_H24, respectively) to understand the basis for KAI2-regulated heat stress tolerance. We discovered that the kai2 mutants exhibited hypersensitivity to high-temperature stress relative to WT plants, which might be associated with a more highly increased leaf surface temperature and cell membrane damage in kai2 mutant plants. Next, we performed comparative transcriptome analysis of kai2_C, kai2_H6, kai2_H24, WT_C, WT_H6 and WT_H24 to identify transcriptome differences between WT and kai2 mutants in response to heat stress. K-mean clustering of normalized gene expression separated the investigated genotypes into three clusters based on heat-treated and non-treated control conditions. Within each cluster, the kai2 mutants were separated from WT plants, implying that kai2 mutants exhibited distinct transcriptome profiles relative to WT plants. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed a repression in 'misfolded protein binding', 'heat shock protein binding', 'unfolded protein binding' and 'protein processing in endoplasmic reticulum' pathways, which was consistent with the downregulation of several genes encoding heat shock proteins and heat shock transcription factors in the kai2 mutant versus WT plants under control and heat stress conditions. Our findings suggest that chemical or genetic manipulation of KAI2 signaling may provide a novel way to improve heat tolerance in plants.
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Affiliation(s)
- Mostafa Abdelrahman
- Faculty of Science, Galala University, Suez, El Sokhna 43511, Egypt
- Botany Department, Faculty of Science, Aswan University, Aswan 81528, Egypt
| | - Mohammad Golam Mostofa
- Department of Plant and Soil Science, Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, Lubbock, TX 79409, USA
| | - Cuong Duy Tran
- Genetic Engineering Department, Agricultural Genetics Institute, Vietnamese Academy of Agricultural Science, Pham Van Dong Street, Hanoi 100000, Viet Nam
| | - Magdi El-Sayed
- Faculty of Science, Galala University, Suez, El Sokhna 43511, Egypt
| | - Weiqiang Li
- Jilin Da'an Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, Kaifeng 475001, China
| | - Saad Sulieman
- Department of Agronomy, Faculty of Agriculture, University of Khartoum, Shambat, Khartoum North 13314, Sudan
| | - Maho Tanaka
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, Saitama, 351-0198 Japan
| | - Motoaki Seki
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, Saitama, 351-0198 Japan
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, 244-0813 Japan
| | - Lam-Son Phan Tran
- Department of Plant and Soil Science, Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, Lubbock, TX 79409, USA
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14
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Feng Z, Liang X, Tian H, Watanabe Y, Nguyen KH, Tran CD, Abdelrahman M, Xu K, Mostofa MG, Ha CV, Mochida K, Tian C, Tanaka M, Seki M, Liang Z, Miao Y, Tran LSP, Li W. SUPPRESSOR of MAX2 1 (SMAX1) and SMAX1-LIKE2 (SMXL2) Negatively Regulate Drought Resistance in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2023; 63:1900-1913. [PMID: 35681253 DOI: 10.1093/pcp/pcac080] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/13/2022] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
Recent investigations in Arabidopsis thaliana suggest that SUPPRESSOR of MORE AXILLARY GROWTH 2 1 (SMAX1) and SMAX1-LIKE2 (SMXL2) are negative regulators of karrikin (KAR) and strigolactone (SL) signaling during plant growth and development, but their functions in drought resistance and related mechanisms of action remain unclear. To understand the roles and mechanisms of SMAX1 and SMXL2 in drought resistance, we investigated the drought-resistance phenotypes and transcriptome profiles of smax1 smxl2 (s1,2) double-mutant plants in response to drought stress. The s1,2 mutant plants showed enhanced drought-resistance and lower leaf water loss when compared with wild-type (WT) plants. Transcriptome comparison of rosette leaves from the s1,2 mutant and the WT under normal and dehydration conditions suggested that the mechanism related to cuticle formation was involved in drought resistance. This possibility was supported by enhanced cuticle formation in the rosette leaves of the s1,2 mutant. We also found that the s1,2 mutant plants were more sensitive to abscisic acid in assays of stomatal closure, cotyledon opening, chlorophyll degradation and growth inhibition, and they showed a higher reactive oxygen species detoxification capacity than WT plants. In addition, the s1,2 mutant plants had longer root hairs and a higher root-to-shoot ratio than the WT plants, suggesting that the mutant had a greater capacity for water absorption than the WT. Taken together, our results indicate that SMAX1 and SMXL2 negatively regulate drought resistance, and disruption of these KAR- and SL-signaling-related genes may therefore provide a novel means for improving crop drought resistance.
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Affiliation(s)
- Zhonghui Feng
- Jilin Daan Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, No. 4888 Shengbei Street, Changchun 130102, China
- College of Life Science, Baicheng Normal University, No. 57, Zhongxing West Road, Taobei District, Baicheng 137000, China
- University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Xiaohan Liang
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Hongtao Tian
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Yasuko Watanabe
- Bioproductivity Informatics Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
| | - Kien Huu Nguyen
- National Key Laboratory for Plant Cell Biotechnology, Agricultural Genetics Institute, Vietnam Academy of Agricultural Science, Pham Van Dong Street, Hanoi 100000, Vietnam
| | - Cuong Duy Tran
- Genetic Engineering Department, Agricultural Genetics Institute, Vietnamese Academy of Agricultural Science, Pham Van Dong Street, Hanoi 100000, Vietnam
| | - Mostafa Abdelrahman
- Botany Department, Faculty of Science, Aswan University, Aswan 81528, Egypt
- Molecular Biotechnology Program, Faculty of Science, Galala University, Suze, New Galala 43511, Egypt
| | - Kun Xu
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Mohammad Golam Mostofa
- Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, 1006 Canton Ave, Lubbock, TX 79409, USA
| | - Chien Van Ha
- Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, 1006 Canton Ave, Lubbock, TX 79409, USA
| | - Keiichi Mochida
- Bioproductivity Informatics Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka-tyo, Totsuka, Yokohama, 244-0813 Japan
- RIKEN Baton Zone Program, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
- School of Information and Data Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521 Japan
| | - Chunjie Tian
- Jilin Daan Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, No. 4888 Shengbei Street, Changchun 130102, China
| | - Maho Tanaka
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako 351-0198, Japan
| | - Motoaki Seki
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045 Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako 351-0198, Japan
| | - Zhengwei Liang
- Jilin Daan Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, No. 4888 Shengbei Street, Changchun 130102, China
| | - Yuchen Miao
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Lam-Son Phan Tran
- Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, 1006 Canton Ave, Lubbock, TX 79409, USA
| | - Weiqiang Li
- Jilin Daan Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, No. 4888 Shengbei Street, Changchun 130102, China
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
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15
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Trasoletti M, Visentin I, Campo E, Schubert A, Cardinale F. Strigolactones as a hormonal hub for the acclimation and priming to environmental stress in plants. PLANT, CELL & ENVIRONMENT 2022; 45:3611-3630. [PMID: 36207810 PMCID: PMC9828678 DOI: 10.1111/pce.14461] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/29/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
Strigolactones are phytohormones with many attributed roles in development, and more recently in responses to environmental stress. We will review evidence of the latter in the frame of the classic distinction among the three main stress acclimation strategies (i.e., avoidance, tolerance and escape), by taking osmotic stress in its several facets as a non-exclusive case study. The picture we will sketch is that of a hormonal family playing important roles in each of the mechanisms tested so far, and influencing as well the build-up of environmental memory through priming. Thus, strigolactones appear to be backstage operators rather than frontstage players, setting the tune of acclimation responses by fitting them to the plant individual history of stress experience.
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Affiliation(s)
| | | | - Eva Campo
- DISAFA, PlantStressLabTurin UniversityTurinItaly
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16
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Tian H, Watanabe Y, Nguyen KH, Tran CD, Abdelrahman M, Liang X, Xu K, Sepulveda C, Mostofa MG, Van Ha C, Nelson DC, Mochida K, Tian C, Tanaka M, Seki M, Miao Y, Tran LSP, Li W. KARRIKIN UPREGULATED F-BOX 1 negatively regulates drought tolerance in Arabidopsis. PLANT PHYSIOLOGY 2022; 190:2671-2687. [PMID: 35822606 PMCID: PMC9706471 DOI: 10.1093/plphys/kiac336] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
The karrikin (KAR) receptor and several related signaling components have been identified by forward genetic screening, but only a few studies have reported on upstream and downstream KAR signaling components and their roles in drought tolerance. Here, we characterized the functions of KAR UPREGULATED F-BOX 1 (KUF1) in drought tolerance using a reverse genetics approach in Arabidopsis (Arabidopsis thaliana). We observed that kuf1 mutant plants were more tolerant to drought stress than wild-type (WT) plants. To clarify the mechanisms by which KUF1 negatively regulates drought tolerance, we performed physiological, transcriptome, and morphological analyses. We found that kuf1 plants limited leaf water loss by reducing stomatal aperture and cuticular permeability. In addition, kuf1 plants showed increased sensitivity of stomatal closure, seed germination, primary root growth, and leaf senescence to abscisic acid (ABA). Genome-wide transcriptome comparisons of kuf1 and WT rosette leaves before and after dehydration showed that the differences in various drought tolerance-related traits were accompanied by differences in the expression of genes associated with stomatal closure (e.g. OPEN STOMATA 1), lipid and fatty acid metabolism (e.g. WAX ESTER SYNTHASE), and ABA responsiveness (e.g. ABA-RESPONSIVE ELEMENT 3). The kuf1 mutant plants had higher root/shoot ratios and root hair densities than WT plants, suggesting that they could absorb more water than WT plants. Together, these results demonstrate that KUF1 negatively regulates drought tolerance by modulating various physiological traits, morphological adjustments, and ABA responses and that the genetic manipulation of KUF1 in crops is a potential means of enhancing their drought tolerance.
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Affiliation(s)
- Hongtao Tian
- Jilin Da’an Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Yasuko Watanabe
- Bioproductivity Informatics Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
| | - Kien Huu Nguyen
- National Key Laboratory for Plant Cell Biotechnology, Agricultural Genetics Institute, Vietnam Academy of Agricultural Science, Pham-Van-Dong Str., Hanoi, 100000, Vietnam
| | - Cuong Duy Tran
- National Key Laboratory for Plant Cell Biotechnology, Agricultural Genetics Institute, Vietnam Academy of Agricultural Science, Pham-Van-Dong Str., Hanoi, 100000, Vietnam
| | - Mostafa Abdelrahman
- Botany Department, Faculty of Science, Aswan University, Aswan 81528, Egypt
- Molecular Biotechnology Program, Faculty of Science, Galala University, Suze, New Galala 43511, Egypt
| | - Xiaohan Liang
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Kun Xu
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | - Claudia Sepulveda
- Department of Botany & Plant Sciences, University of California, Riverside, California 92521, USA
| | - Mohammad Golam Mostofa
- Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, Lubbock, Texas 79409, USA
| | - Chien Van Ha
- Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, Lubbock, Texas 79409, USA
| | - David C Nelson
- Department of Botany & Plant Sciences, University of California, Riverside, California 92521, USA
| | - Keiichi Mochida
- Bioproductivity Informatics Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
- Microalgae Production Control Technology Laboratory, RIKEN Baton Zone Program, RIKEN Cluster for Science, Technology and Innovation Hub, Yokohama, Japan
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
- Graduate School of Nanobioscience, Yokohama City University, Yokohama, Japan
- School of Information and Data Sciences, Nagasaki University, Nagasaki, Japan
| | - Chunjie Tian
- Jilin Da’an Agro-ecosystem National Observation Research Station, Changchun Jingyuetan Remote Sensing Experiment Station, Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
| | - Maho Tanaka
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, Yokohama, Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, Wako, Japan
| | - Motoaki Seki
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, Yokohama, Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, Wako, Japan
| | - Yuchen Miao
- State Key Laboratory of Cotton Biology, Henan Joint International Laboratory for Crop Multi-Omics Research, School of Life Sciences, Henan University, No. 85 Jinming Road, Kaifeng 475004, China
| | | | - Weiqiang Li
- Author for correspondence: or (W.L.), (L.-S.P.T.)
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17
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Temmerman A, Marquez-Garcia B, Depuydt S, Bruznican S, De Cuyper C, De Keyser A, Boyer FD, Vereecke D, Struk S, Goormachtig S. MAX2-dependent competence for callus formation and shoot regeneration from Arabidopsis thaliana root explants. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:6272-6291. [PMID: 35738874 DOI: 10.1093/jxb/erac281] [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: 03/28/2022] [Accepted: 06/23/2022] [Indexed: 05/21/2023]
Abstract
Although the division of the pericycle cells initiates both lateral root development and root-derived callus formation, these developmental processes are affected differently in the strigolactone and karrikin/KARRIKIN INSENSITIVE 2 (KAI2) ligand signalling mutant more axillary growth 2 (max2). Whereas max2 produces more lateral roots than the wild type, it is defective in the regeneration of shoots from root explants. We suggest that the decreased shoot regeneration of max2 originates from delayed formation of callus primordium, yielding less callus material to regenerate shoots. Indeed, when incubated on callus-inducing medium, the pericycle cell division was reduced in max2 and the early gene expression varied when compared with the wild type, as determined by a transcriptomics analysis. Furthermore, the expression of the LATERAL ORGAN BOUNDARIES DOMAIN genes and of callus-induction genes was modified in correlation with the max2 phenotype, suggesting a role for MAX2 in the regulation of the interplay between cytokinin, auxin, and light signalling in callus initiation. Additionally, we found that the in vitro shoot regeneration phenotype of max2 might be caused by a defect in KAI2, rather than in DWARF14, signalling. Nevertheless, the shoot regeneration assays revealed that the strigolactone biosynthesis mutants max3 and max4 also play a minor role.
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Affiliation(s)
- Arne Temmerman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
| | - Belen Marquez-Garcia
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
| | - Stephen Depuydt
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
- Laboratory of Plant Growth Analysis, Ghent University Global Campus, Songdomunhwa-Ro, Yeonsu-Gu, Incheon, Korea
| | - Silvia Bruznican
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
| | - Carolien De Cuyper
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
| | - Annick De Keyser
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
| | - François-Didier Boyer
- Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Danny Vereecke
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Valentin Vaerwyckweg, Ghent, Belgium
| | - Sylwia Struk
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
| | - Sofie Goormachtig
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Technologiepark, Ghent, Belgium
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18
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Tal L, Palayam M, Ron M, Young A, Britt A, Shabek N. A conformational switch in the SCF-D3/MAX2 ubiquitin ligase facilitates strigolactone signalling. NATURE PLANTS 2022; 8:561-573. [PMID: 35484202 DOI: 10.1038/s41477-022-01145-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 03/28/2022] [Indexed: 05/22/2023]
Abstract
Strigolactones (SLs) are a class of plant hormones that regulate numerous processes of growth and development. SL perception and signal activation involves interaction between F-box E3 ubiquitin ligase D3/MAX2 and DWARF14 (D14) α/β-hydrolase in a SL-dependent manner and targeting of D53/SMXL6/7/8 transcriptional repressors (SMXLs) for proteasome-mediated degradation. D3/MAX2 has been shown to exist in multiple conformational states in which the C-terminal helix (CTH) undergoes a closed-to-open dynamics and regulates D14 binding and SL perception. Despite the multiple modes of D3-D14 interactions found in vitro, the residues that regulate the conformational switch of D3/MAX2 CTH in targeting D53/SMXLs and the subsequent effect on SL signalling remain unclear. Here we elucidate the functional dynamics of ASK1-D3/MAX2 in SL signalling by leveraging conformational switch mutants in vitro and in plants. We report the crystal structure of a dislodged CTH of the ASK1-D3 mutant and demonstrate that disruptions in CTH plasticity via either CRISPR-Cas9 genome editing or expression of point mutation mutants result in impairment of SL signalling. We show that the conformational switch in ASK1-D3/MAX2 CTH directly regulates ubiquitin-mediated protein degradation. A dislodged conformation involved in D53/SMXLs SL-dependent recruitment and ubiquitination and an engaged conformation are required for the release of polyubiquitinated D53/SMXLs and subsequently D14 for proteasomal degradation. Finally, we uncovered an organic acid metabolite that can directly trigger the D3/MAX2 CTH conformational switch. Our findings unravel a new regulatory function of a SKP1-CUL1-F-box ubiquitin ligase in plant signalling.
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Affiliation(s)
- Lior Tal
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, USA
| | - Malathy Palayam
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, USA
| | - Mily Ron
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, USA
| | - Aleczander Young
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, USA
| | - Anne Britt
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, USA
| | - Nitzan Shabek
- Department of Plant Biology, College of Biological Sciences, University of California - Davis, Davis, CA, USA.
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19
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Li Q, Martín-Fontecha ES, Khosla A, White AR, Chang S, Cubas P, Nelson DC. The strigolactone receptor D14 targets SMAX1 for degradation in response to GR24 treatment and osmotic stress. PLANT COMMUNICATIONS 2022; 3:100303. [PMID: 35529949 PMCID: PMC9073322 DOI: 10.1016/j.xplc.2022.100303] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/15/2021] [Accepted: 01/25/2022] [Indexed: 05/25/2023]
Abstract
The effects of the phytohormone strigolactone (SL) and smoke-derived karrikins (KARs) on plants are generally distinct, despite the fact that they are perceived through very similar mechanisms. The homologous receptors DWARF14 (D14) and KARRIKIN-INSENSITIVE2 (KAI2), together with the F-box protein MORE AXILLARY GROWTH2 (MAX2), mediate SL and KAR responses, respectively, by targeting different SMAX1-LIKE (SMXL) family proteins for degradation. These mechanisms are putatively well-insulated, with D14-MAX2 targeting SMXL6, SMXL7, and SMXL8 and KAI2-MAX2 targeting SMAX1 and SMXL2 in Arabidopsis thaliana. Recent evidence challenges this model. We investigated whether D14 can target SMAX1 and whether this occurs naturally. Genetic analysis indicates that the SL analog GR24 promotes D14-SMAX1 crosstalk. Although D14 shows weaker interactions with SMAX1 than with SMXL2 or SMXL7, D14 mediates GR24-induced degradation of SMAX1 in plants. Osmotic stress triggers SMAX1 degradation, which is protective, through SL biosynthesis and signaling genes. Thus, D14-SMAX1 crosstalk may be beneficial and not simply a vestige of the evolution of the SL pathway.
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Affiliation(s)
- Qingtian Li
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
| | - Elena Sánchez Martín-Fontecha
- Plant Molecular Genetics Department, Centro Nacional de Biotecnología/CSIC, Campus Universidad Autόnoma de Madrid, Madrid, Spain
| | - Aashima Khosla
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
| | - Alexandra R.F. White
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
| | - Sunhyun Chang
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
| | - Pilar Cubas
- Plant Molecular Genetics Department, Centro Nacional de Biotecnología/CSIC, Campus Universidad Autόnoma de Madrid, Madrid, Spain
| | - David C. Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
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20
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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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21
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Meng Y, Varshney K, Incze N, Badics E, Kamran M, Davies SF, Oppermann LMF, Magne K, Dalmais M, Bendahmane A, Sibout R, Vogel J, Laudencia-Chingcuanco D, Bond CS, Soós V, Gutjahr C, Waters MT. KARRIKIN INSENSITIVE2 regulates leaf development, root system architecture and arbuscular-mycorrhizal symbiosis in Brachypodium distachyon. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:1559-1574. [PMID: 34953105 DOI: 10.1111/tpj.15651] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
KARRIKIN INSENSITIVE2 (KAI2) is an α/β-hydrolase required for plant responses to karrikins, which are abiotic butenolides that can influence seed germination and seedling growth. Although represented by four angiosperm species, loss-of-function kai2 mutants are phenotypically inconsistent and incompletely characterised, resulting in uncertainties about the core functions of KAI2 in plant development. Here we characterised the developmental functions of KAI2 in the grass Brachypodium distachyon using molecular, physiological and biochemical approaches. Bdkai2 mutants exhibit increased internode elongation and reduced leaf chlorophyll levels, but only a modest increase in water loss from detached leaves. Bdkai2 shows increased numbers of lateral roots and reduced root hair growth, and fails to support normal root colonisation by arbuscular-mycorrhizal (AM) fungi. The karrikins KAR1 and KAR2 , and the strigolactone (SL) analogue rac-GR24, each elicit overlapping but distinct changes to the shoot transcriptome via BdKAI2. Finally, we show that BdKAI2 exhibits a clear ligand preference for desmethyl butenolides and weak responses to methyl-substituted SL analogues such as GR24. Our findings suggest that KAI2 has multiple roles in shoot development, root system development and transcriptional regulation in grasses. Although KAI2-dependent AM symbiosis is likely conserved within monocots, the magnitude of the effect of KAI2 on water relations may vary across angiosperms.
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Affiliation(s)
- Yongjie Meng
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
| | - Kartikye Varshney
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich, Freising, 85354, Germany
| | - Norbert Incze
- Department of Biological Resources, Agricultural Institute, Centre for Agricultural Research, Martonvásár, 2462, Hungary
- Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, 1117, Hungary
| | - Eszter Badics
- Department of Biological Resources, Agricultural Institute, Centre for Agricultural Research, Martonvásár, 2462, Hungary
- Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, 1117, Hungary
| | - Muhammad Kamran
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Sabrina F Davies
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Larissa M F Oppermann
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Kévin Magne
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, 91405, France
- Université de Paris, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, 91405, France
| | - Marion Dalmais
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, 91405, France
- Université de Paris, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, 91405, France
| | - Abdel Bendahmane
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, 91405, France
- Université de Paris, CNRS, INRAE, Institute of Plant Sciences Paris-Saclay (IPS2), Orsay, 91405, France
| | - Richard Sibout
- Institut Jean-Pierre Bourgin, UMR1318 INRAE-AgroParisTech, Versailles Cedex, F-78026, France
- UR1268 BIA, INRAE, Nantes, 44300, France
| | - John Vogel
- DOE Joint Genome Institute, Berkeley, California, 94720, USA
| | | | - Charles S Bond
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Vilmos Soós
- Department of Biological Resources, Agricultural Institute, Centre for Agricultural Research, Martonvásár, 2462, Hungary
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich, Freising, 85354, Germany
| | - Mark T Waters
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
- College of Agronomy, Sichuan Agricultural University, Chengdu, 611130, China
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22
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Guercio AM, Torabi S, Cornu D, Dalmais M, Bendahmane A, Le Signor C, Pillot JP, Le Bris P, Boyer FD, Rameau C, Gutjahr C, de Saint Germain A, Shabek N. Structural and functional analyses explain Pea KAI2 receptor diversity and reveal stereoselective catalysis during signal perception. Commun Biol 2022; 5:126. [PMID: 35149763 PMCID: PMC8837635 DOI: 10.1038/s42003-022-03085-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 01/28/2022] [Indexed: 11/10/2022] Open
Abstract
KAI2 proteins are plant α/β hydrolase receptors which perceive smoke-derived butenolide signals and endogenous, yet unidentified KAI2-ligands (KLs). The number of functional KAI2 receptors varies among species and KAI2 gene duplication and sub-functionalization likely plays an adaptative role by altering specificity towards different KLs. Legumes represent one of the largest families of flowering plants and contain many agronomic crops. Prior to their diversification, KAI2 underwent duplication resulting in KAI2A and KAI2B. Here we demonstrate that Pisum sativum KAI2A and KAI2B are active receptors and enzymes with divergent ligand stereoselectivity. KAI2B has a higher affinity for and hydrolyses a broader range of substrates including strigolactone-like stereoisomers. We determine the crystal structures of PsKAI2B in apo and butenolide-bound states. The biochemical, structural, and mass spectra analyses of KAI2s reveal a transient intermediate on the catalytic serine and a stable adduct on the catalytic histidine, confirming its role as a bona fide enzyme. Our work uncovers the stereoselectivity of ligand perception and catalysis by diverged KAI2 receptors and proposes adaptive sensitivity to KAR/KL and strigolactones by KAI2B.
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Affiliation(s)
- Angelica M Guercio
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA, 95616, USA
| | - Salar Torabi
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), 85354, Freising, Germany
| | - David Cornu
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Marion Dalmais
- Institute of Plant Sciences Paris-Saclay, INRAE, CNRS, Université Paris-Saclay, 91405, Orsay, France
| | - Abdelhafid Bendahmane
- Institute of Plant Sciences Paris-Saclay, INRAE, CNRS, Université Paris-Saclay, 91405, Orsay, France
| | - Christine Le Signor
- Agroecologie, AgroSup Dijon, INRAE, Université Bourgogne Franche Comte, 21000, Dijon, France
| | - Jean-Paul Pillot
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Philippe Le Bris
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - François-Didier Boyer
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France
| | - Catherine Rameau
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), 85354, Freising, Germany
| | | | - Nitzan Shabek
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA, 95616, USA.
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23
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Struk S, Braem L, Matthys C, Walton A, Vangheluwe N, Van Praet S, Jiang L, Baster P, De Cuyper C, Boyer FD, Stes E, Beeckman T, Friml J, Gevaert K, Goormachtig S. Transcriptional Analysis in the Arabidopsis Roots Reveals New Regulators that Link rac-GR24 Treatment with Changes in Flavonol Accumulation, Root Hair Elongation and Lateral Root Density. PLANT & CELL PHYSIOLOGY 2022; 63:104-119. [PMID: 34791413 DOI: 10.1093/pcp/pcab149] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/06/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
The synthetic strigolactone (SL) analog, rac-GR24, has been instrumental in studying the role of SLs as well as karrikins because it activates the receptors DWARF14 (D14) and KARRIKIN INSENSITIVE 2 (KAI2) of their signaling pathways, respectively. Treatment with rac-GR24 modifies the root architecture at different levels, such as decreasing the lateral root density (LRD), while promoting root hair elongation or flavonol accumulation. Previously, we have shown that the flavonol biosynthesis is transcriptionally activated in the root by rac-GR24 treatment, but, thus far, the molecular players involved in that response have remained unknown. To get an in-depth insight into the changes that occur after the compound is perceived by the roots, we compared the root transcriptomes of the wild type and the more axillary growth2 (max2) mutant, affected in both SL and karrikin signaling pathways, with and without rac-GR24 treatment. Quantitative reverse transcription (qRT)-PCR, reporter line analysis and mutant phenotyping indicated that the flavonol response and the root hair elongation are controlled by the ELONGATED HYPOCOTYL 5 (HY5) and MYB12 transcription factors, but HY5, in contrast to MYB12, affects the LRD as well. Furthermore, we identified the transcription factors TARGET OF MONOPTEROS 5 (TMO5) and TMO5 LIKE1 as negative and the Mediator complex as positive regulators of the rac-GR24 effect on LRD. Altogether, hereby, we get closer toward understanding the molecular mechanisms that underlay the rac-GR24 responses in the root.
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Affiliation(s)
- Sylwia Struk
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - Lukas Braem
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
- Department of Biomolecular Medicine, Ghent University, Technologiepark 75, Ghent 9052, Belgium
- Center for Medical Biotechnology, VIB, Technologiepark 75, Ghent 9052, Belgium
| | - Cedrick Matthys
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - Alan Walton
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
- Department of Biomolecular Medicine, Ghent University, Technologiepark 75, Ghent 9052, Belgium
- Center for Medical Biotechnology, VIB, Technologiepark 75, Ghent 9052, Belgium
| | - Nick Vangheluwe
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - Stan Van Praet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
- Laboratory of Plant Growth Analysis, Ghent University Global Campus, 119 Songdomunhwa-Ro, Yeonsu-Gu, Incheon 21985, Republic of Korea
| | - Lingxiang Jiang
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - Pawel Baster
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - Carolien De Cuyper
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - François-Didier Boyer
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, AgroParisTech, Centre National de la Recherche Scientifique, Université Paris-Saclay, Route de Saint-Cyr, Versailles 78026, France
- Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, UPR2301, Université Paris-Sud, Université Paris-Saclay, 1 Avenue de la Terrasse, Gif-sur-Yvette 91198, France
| | - Elisabeth Stes
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
- Department of Biomolecular Medicine, Ghent University, Technologiepark 75, Ghent 9052, Belgium
- Center for Medical Biotechnology, VIB, Technologiepark 75, Ghent 9052, Belgium
| | - Tom Beeckman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
| | - Jiří Friml
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
- Institute of Science and Technology (IST) Austria, Cell Biology Laboratory, Am Campus 1, Klosterneuburg 3400, Austria
| | - Kris Gevaert
- Department of Biomolecular Medicine, Ghent University, Technologiepark 75, Ghent 9052, Belgium
- Center for Medical Biotechnology, VIB, Technologiepark 75, Ghent 9052, Belgium
| | - Sofie Goormachtig
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, Ghent 9052, Belgium
- Center of Plant Systems Biology, VIB, Technologiepark 71, Ghent 9052, Belgium
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24
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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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25
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de Saint Germain A, Jacobs A, Brun G, Pouvreau JB, Braem L, Cornu D, Clavé G, Baudu E, Steinmetz V, Servajean V, Wicke S, Gevaert K, Simier P, Goormachtig S, Delavault P, Boyer FD. A Phelipanche ramosa KAI2 protein perceives strigolactones and isothiocyanates enzymatically. PLANT COMMUNICATIONS 2021; 2:100166. [PMID: 34746757 PMCID: PMC8553955 DOI: 10.1016/j.xplc.2021.100166] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 01/25/2021] [Accepted: 01/31/2021] [Indexed: 05/18/2023]
Abstract
Phelipanche ramosa is an obligate root-parasitic weed that threatens major crops in central Europe. In order to germinate, it must perceive various structurally divergent host-exuded signals, including isothiocyanates (ITCs) and strigolactones (SLs). However, the receptors involved are still uncharacterized. Here, we identify five putative SL receptors in P. ramosa and show that PrKAI2d3 is involved in the stimulation of seed germination. We demonstrate the high plasticity of PrKAI2d3, which allows it to interact with different chemicals, including ITCs. The SL perception mechanism of PrKAI2d3 is similar to that of endogenous SLs in non-parasitic plants. We provide evidence that PrKAI2d3 enzymatic activity confers hypersensitivity to SLs. Additionally, we demonstrate that methylbutenolide-OH binds PrKAI2d3 and stimulates P. ramosa germination with bioactivity comparable to that of ITCs. This study demonstrates that P. ramosa has extended its signal perception system during evolution, a fact that should be considered for the development of specific and efficient biocontrol methods.
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Affiliation(s)
| | - Anse Jacobs
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Center for Medical Biotechnology, VIB, 9000 Ghent, Belgium
| | - Guillaume Brun
- Laboratoire de Biologie et Pathologie Végétales (LBPV), Equipe d’Accueil 1157, Université de Nantes, 44000 Nantes, France
- Institute for Biology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Jean-Bernard Pouvreau
- Laboratoire de Biologie et Pathologie Végétales (LBPV), Equipe d’Accueil 1157, Université de Nantes, 44000 Nantes, France
| | - Lukas Braem
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Center for Medical Biotechnology, VIB, 9000 Ghent, Belgium
| | - David Cornu
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Guillaume Clavé
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France
| | - Emmanuelle Baudu
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Vincent Steinmetz
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France
| | - Vincent Servajean
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France
| | - Susann Wicke
- Institute for Biology, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Kris Gevaert
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Center for Medical Biotechnology, VIB, 9000 Ghent, Belgium
| | - Philippe Simier
- Laboratoire de Biologie et Pathologie Végétales (LBPV), Equipe d’Accueil 1157, Université de Nantes, 44000 Nantes, France
| | - Sofie Goormachtig
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Gent, Belgium
| | - Philippe Delavault
- Laboratoire de Biologie et Pathologie Végétales (LBPV), Equipe d’Accueil 1157, Université de Nantes, 44000 Nantes, France
| | - François-Didier Boyer
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France
- Corresponding author
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Bursch K, Niemann ET, Nelson DC, Johansson H. Karrikins control seedling photomorphogenesis and anthocyanin biosynthesis through a HY5-BBX transcriptional module. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1346-1362. [PMID: 34160854 DOI: 10.1111/tpj.15383] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 06/18/2021] [Indexed: 05/15/2023]
Abstract
The butenolide molecule, karrikin (KAR), emerging in smoke of burned plant material, enhances light responses such as germination, inhibition of hypocotyl elongation, and anthocyanin accumulation in Arabidopsis. The KAR signaling pathway consists of KARRIKIN INSENSITIVE 2 (KAI2) and MORE AXILLARY GROWTH 2 (MAX2), which, upon activation, act in an SCF E3 ubiquitin ligase complex to target the downstream signaling components SUPPRESSOR OF MAX2 1 (SMAX1) and SMAX1-LIKE 2 (SMXL2) for degradation. How degradation of SMAX1 and SMXL2 is translated into growth responses remains unknown. Although light clearly influences the activity of KAR, the molecular connection between the two pathways is still poorly understood. Here, we demonstrate that the KAR signaling pathway promotes the activity of a transcriptional module consisting of ELONGATED HYPOCOTYL 5 (HY5), B-BOX DOMAIN PROTEIN 20 (BBX20), and BBX21. The bbx20 bbx21 mutant is largely insensitive to treatment with KAR2 , similar to a hy5 mutant, with regards to inhibition of hypocotyl elongation and anthocyanin accumulation. Detailed analysis of higher order mutants in combination with RNA-sequencing analysis revealed that anthocyanin accumulation downstream of SMAX1 and SMXL2 is fully dependent on the HY5-BBX module. However, the promotion of hypocotyl elongation by SMAX1 and SMXL2 is, in contrast to KAR2 treatment, only partially dependent on BBX20, BBX21, and HY5. Taken together, these results suggest that light- and KAR-dependent signaling intersect at the HY5-BBX transcriptional module.
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Affiliation(s)
- Katharina Bursch
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences (DCPS), Freie Universität Berlin, Berlin, 14195, Germany
| | - Ella T Niemann
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences (DCPS), Freie Universität Berlin, Berlin, 14195, Germany
| | - David C Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
| | - Henrik Johansson
- Institute of Biology/Applied Genetics, Dahlem Centre of Plant Sciences (DCPS), Freie Universität Berlin, Berlin, 14195, Germany
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27
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Hull R, Choi J, Paszkowski U. Conditioning plants for arbuscular mycorrhizal symbiosis through DWARF14-LIKE signalling. CURRENT OPINION IN PLANT BIOLOGY 2021; 62:102071. [PMID: 34186295 PMCID: PMC8425181 DOI: 10.1016/j.pbi.2021.102071] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/11/2021] [Accepted: 05/24/2021] [Indexed: 06/13/2023]
Abstract
The evolutionarily ancient α/β hydrolase DWARF14-LIKE (D14L) is indispensable for the perception of beneficial arbuscular mycorrhizal (AM) fungi in the rhizosphere, and for a range of developmental processes. Variants of D14L recognise natural strigolactones and the smoke constituent karrikin, both classified as butenolides, and additional unknown ligand(s), critical for symbiosis and development. Recent advances in the understanding of downstream effects of D14L signalling include biochemical evidence for the degradation of the repressor SMAX1. Indeed, genetic removal of rice SMAX1 leads to the de-repression of symbiosis programmes and to the simultaneous increase in strigolactone production. As strigolactones are key to attraction of the fungus in the rhizosphere, the D14L signalling pathway appears to coordinate fungal stimulation and root symbiotic competency. Here, we discuss the possible integrative roles of D14L signalling in conditioning plants for AM symbiosis.
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Affiliation(s)
- Raphaella Hull
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | - Jeongmin Choi
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | - Uta Paszkowski
- Crop Science Centre, Department of Plant Sciences, University of Cambridge, Lawrence Weaver Road, Cambridge CB3 0LE, UK.
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Yao J, Scaffidi A, Meng Y, Melville KT, Komatsu A, Khosla A, Nelson DC, Kyozuka J, Flematti GR, Waters MT. Desmethyl butenolides are optimal ligands for karrikin receptor proteins. THE NEW PHYTOLOGIST 2021; 230:1003-1016. [PMID: 33474738 DOI: 10.1111/nph.17224] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/16/2021] [Indexed: 05/25/2023]
Abstract
Strigolactones and karrikins are butenolide molecules that regulate plant growth. They are perceived by the α/β-hydrolase DWARF14 (D14) and its homologue KARRIKIN INSENSITIVE2 (KAI2), respectively. Plant-derived strigolactones have a butenolide ring with a methyl group that is essential for bioactivity. By contrast, karrikins are abiotic in origin, and the butenolide methyl group is nonessential. KAI2 is probably a receptor for an endogenous butenolide, but the identity of this compound remains unknown. Here we characterise the specificity of KAI2 towards differing butenolide ligands using genetic and biochemical approaches. We find that KAI2 proteins from multiple species are most sensitive to desmethyl butenolides that lack a methyl group. Desmethyl-GR24 and desmethyl-CN-debranone are active by KAI2 but not D14. They are more potent KAI2 agonists compared with their methyl-substituted reference compounds both in vitro and in plants. The preference of KAI2 for desmethyl butenolides is conserved in Selaginella moellendorffii and Marchantia polymorpha, suggesting that it is an ancient trait in land plant evolution. Our findings provide insight into the mechanistic basis for differential ligand perception by KAI2 and D14, and support the view that the endogenous substrates for KAI2 and D14 have distinct chemical structures and biosynthetic origins.
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Affiliation(s)
- Jiaren Yao
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
| | - Adrian Scaffidi
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Yongjie Meng
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
| | - Kim T Melville
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
| | - Aino Komatsu
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
| | - Aashima Khosla
- 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
| | - Junko Kyozuka
- Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
| | - Gavin R Flematti
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Mark T Waters
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, WA, 6009, Australia
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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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30
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Cell kinetics of auxin transport and activity in Arabidopsis root growth and skewing. Nat Commun 2021; 12:1657. [PMID: 33712581 PMCID: PMC7954861 DOI: 10.1038/s41467-021-21802-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 02/09/2021] [Indexed: 12/31/2022] Open
Abstract
Auxin is a key regulator of plant growth and development. Local auxin biosynthesis and intercellular transport generates regional gradients in the root that are instructive for processes such as specification of developmental zones that maintain root growth and tropic responses. Here we present a toolbox to study auxin-mediated root development that features: (i) the ability to control auxin synthesis with high spatio-temporal resolution and (ii) single-cell nucleus tracking and morphokinetic analysis infrastructure. Integration of these two features enables cutting-edge analysis of root development at single-cell resolution based on morphokinetic parameters under normal growth conditions and during cell-type-specific induction of auxin biosynthesis. We show directional auxin flow in the root and refine the contributions of key players in this process. In addition, we determine the quantitative kinetics of Arabidopsis root meristem skewing, which depends on local auxin gradients but does not require PIN2 and AUX1 auxin transporter activities. Beyond the mechanistic insights into root development, the tools developed here will enable biologists to study kinetics and morphology of various critical processes at the single cell-level in whole organisms.
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31
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High-throughput image segmentation and machine learning approaches in the plant sciences across multiple scales. Emerg Top Life Sci 2021; 5:239-248. [DOI: 10.1042/etls20200273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 01/12/2023]
Abstract
Agriculture has benefited greatly from the rise of big data and high-performance computing. The acquisition and analysis of data across biological scales have resulted in strategies modeling inter- actions between plant genotype and environment, models of root architecture that provide insight into resource utilization, and the elucidation of cell-to-cell communication mechanisms that are instrumental in plant development. Image segmentation and machine learning approaches for interpreting plant image data are among many of the computational methodologies that have evolved to address challenging agricultural and biological problems. These approaches have led to contributions such as the accelerated identification of gene that modulate stress responses in plants and automated high-throughput phenotyping for early detection of plant diseases. The continued acquisition of high throughput imaging across multiple biological scales provides opportunities to further push the boundaries of our understandings quicker than ever before. In this review, we explore the current state of the art methodologies in plant image segmentation and machine learning at the agricultural, organ, and cellular scales in plants. We show how the methodologies for segmentation and classification differ due to the diversity of physical characteristics found at these different scales. We also discuss the hardware technologies most commonly used at these different scales, the types of quantitative metrics that can be extracted from these images, and how the biological mechanisms by which plants respond to abiotic/biotic stresses or genotypic modifications can be extracted from these approaches.
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32
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Struk S, De Cuyper C, Jacobs A, Braem L, Walton A, De Keyser A, Depuydt S, Vu LD, De Smet I, Boyer FD, Eeckhout D, Persiau G, Gevaert K, De Jaeger G, Goormachtig S. Unraveling the MAX2 Protein Network in Arabidopsis thaliana: Identification of the Protein Phosphatase PAPP5 as a Novel MAX2 Interactor. Mol Cell Proteomics 2021; 20:100040. [PMID: 33372050 PMCID: PMC7950214 DOI: 10.1074/mcp.ra119.001766] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 12/18/2020] [Accepted: 12/28/2020] [Indexed: 12/12/2022] Open
Abstract
The F-box protein MORE AXILLARY GROWTH 2 (MAX2) is a central component in the signaling cascade of strigolactones (SLs) as well as of the smoke-derived karrikins (KARs) and the so far unknown endogenous KAI2 ligand (KL). The two groups of molecules are involved in overlapping and unique developmental processes, and signal-specific outcomes are attributed to perception by the paralogous α/β-hydrolases DWARF14 (D14) for SL and KARRIKIN INSENSITIVE 2/HYPOSENSITIVE TO LIGHT (KAI2/HTL) for KAR/KL. In addition, depending on which receptor is activated, specific members of the SUPPRESSOR OF MAX2 1 (SMAX1)-LIKE (SMXL) family control KAR/KL and SL responses. As proteins that function in the same signal transduction pathway often occur in large protein complexes, we aimed at discovering new players of the MAX2, D14, and KAI2 protein network by tandem affinity purification in Arabidopsis cell cultures. When using MAX2 as a bait, various proteins were copurified, among which were general components of the Skp1-Cullin-F-box complex and members of the CONSTITUTIVE PHOTOMORPHOGENIC 9 signalosome. Here, we report the identification of a novel interactor of MAX2, a type 5 serine/threonine protein phosphatase, designated PHYTOCHROME-ASSOCIATED PROTEIN PHOSPHATASE 5 (PAPP5). Quantitative affinity purification pointed at PAPP5 as being more present in KAI2 rather than in D14 protein complexes. In agreement, mutant analysis suggests that PAPP5 modulates KAR/KL-dependent seed germination under suboptimal conditions and seedling development. In addition, a phosphopeptide enrichment experiment revealed that PAPP5 might dephosphorylate MAX2 in vivo independently of the synthetic SL analog, rac-GR24. Together, by analyzing the protein complexes to which MAX2, D14, and KAI2 belong, we revealed a new MAX2 interactor, PAPP5, that might act through dephosphorylation of MAX2 to control mainly KAR/KL-related phenotypes and, hence, provide another link with the light pathway.
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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
| | - Carolien De Cuyper
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Anse Jacobs
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium; Department of Biochemistry, Ghent University, Ghent, Belgium; Center for Medical Biotechnology, VIB, Ghent, Belgium
| | - Lukas Braem
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium; Department of Biochemistry, Ghent University, Ghent, Belgium; Center for Medical Biotechnology, VIB, Ghent, Belgium
| | - Alan Walton
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium; Department of Biochemistry, Ghent University, Ghent, Belgium; Center for Medical Biotechnology, VIB, Ghent, Belgium
| | - Annick De Keyser
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Stephen Depuydt
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Lam Dai Vu
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium; Department of Biochemistry, Ghent University, Ghent, Belgium; Center for Medical Biotechnology, VIB, Ghent, Belgium
| | - Ive De Smet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - François-Didier Boyer
- Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique (INRA), AgroParisTech, Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay, Versailles, France; Institut de Chimie des Substances Naturelles, CNRS Unité Propre de Recherche 2301, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Dominique Eeckhout
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Geert Persiau
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Kris Gevaert
- Department of Biochemistry, Ghent University, Ghent, Belgium; Center for Medical Biotechnology, VIB, Ghent, Belgium
| | - Geert De Jaeger
- 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.
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Mohammad-Sidik A, Sun J, Shin R, Song Z, Ning Y, Matthus E, Wilkins KA, Davies JM. Annexin 1 Is a Component of eATP-Induced Cytosolic Calcium Elevation in Arabidopsis thaliana Roots. Int J Mol Sci 2021; 22:ijms22020494. [PMID: 33419052 PMCID: PMC7825420 DOI: 10.3390/ijms22020494] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/03/2021] [Accepted: 01/04/2021] [Indexed: 12/18/2022] Open
Abstract
Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca2+ ([Ca2+]cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca2+ influx channels involved in eATP-induced [Ca2+]cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca2+ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca2+]cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes.
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Affiliation(s)
- Amirah Mohammad-Sidik
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK; (A.M.-S.); (Y.N.); (E.M.); (K.A.W.)
| | - Jian Sun
- School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China;
| | - Ryoung Shin
- RIKEN Centre for Sustainable Resource Science, Yokohama, Kanagawa 230-0045, Japan;
| | - Zhizhong Song
- School of Agriculture, Ludong University, Yantai 264205, China;
| | - Youzheng Ning
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK; (A.M.-S.); (Y.N.); (E.M.); (K.A.W.)
| | - Elsa Matthus
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK; (A.M.-S.); (Y.N.); (E.M.); (K.A.W.)
| | - Katie A. Wilkins
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK; (A.M.-S.); (Y.N.); (E.M.); (K.A.W.)
| | - Julia M. Davies
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK; (A.M.-S.); (Y.N.); (E.M.); (K.A.W.)
- Correspondence: ; Tel.: +44-1223-333-939
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34
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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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35
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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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36
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Carbonnel S, Torabi S, Griesmann M, Bleek E, Tang Y, Buchka S, Basso V, Shindo M, Boyer FD, Wang TL, Udvardi M, Waters MT, Gutjahr C. Lotus japonicus karrikin receptors display divergent ligand-binding specificities and organ-dependent redundancy. PLoS Genet 2020; 16:e1009249. [PMID: 33370251 PMCID: PMC7808659 DOI: 10.1371/journal.pgen.1009249] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/14/2021] [Accepted: 11/03/2020] [Indexed: 12/15/2022] Open
Abstract
Karrikins (KARs), smoke-derived butenolides, are perceived by the α/β-fold hydrolase KARRIKIN INSENSITIVE2 (KAI2) and thought to mimic endogenous, yet elusive plant hormones tentatively called KAI2-ligands (KLs). The sensitivity to different karrikin types as well as the number of KAI2 paralogs varies among plant species, suggesting diversification and co-evolution of ligand-receptor relationships. We found that the genomes of legumes, comprising a number of important crops with protein-rich, nutritious seed, contain two or more KAI2 copies. We uncover sub-functionalization of the two KAI2 versions in the model legume Lotus japonicus and demonstrate differences in their ability to bind the synthetic ligand GR24ent-5DS in vitro and in genetic assays with Lotus japonicus and the heterologous Arabidopsis thaliana background. These differences can be explained by the exchange of a widely conserved phenylalanine in the binding pocket of KAI2a with a tryptophan in KAI2b, which arose independently in KAI2 proteins of several unrelated angiosperms. Furthermore, two polymorphic residues in the binding pocket are conserved across a number of legumes and may contribute to ligand binding preferences. The diversification of KAI2 binding pockets suggests the occurrence of several different KLs acting in non-fire following plants, or an escape from possible antagonistic exogenous molecules. Unexpectedly, L. japonicus responds to diverse synthetic KAI2-ligands in an organ-specific manner. Hypocotyl growth responds to KAR1, KAR2 and rac-GR24, while root system development responds only to KAR1. This differential responsiveness cannot be explained by receptor-ligand preferences alone, because LjKAI2a is sufficient for karrikin responses in the hypocotyl, while LjKAI2a and LjKAI2b operate redundantly in roots. Instead, it likely reflects differences between plant organs in their ability to transport or metabolise the synthetic KLs. Our findings provide new insights into the evolution and diversity of butenolide ligand-receptor relationships, and open novel research avenues into their ecological significance and the mechanisms controlling developmental responses to divergent KLs.
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Affiliation(s)
- Samy Carbonnel
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
- Technical University of Munich (TUM), TUM School of Life Sciences, Plant Genetics, Freising, Germany
| | - Salar Torabi
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
- Technical University of Munich (TUM), TUM School of Life Sciences, Plant Genetics, Freising, Germany
| | - Maximilian Griesmann
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
| | - Elias Bleek
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
| | - Yuhong Tang
- Noble Research Institute, Ardmore, Oklahoma, United States of America
| | - Stefan Buchka
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
| | - Veronica Basso
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
| | - Mitsuru Shindo
- Institute for Materials Chemistry and Engineering, Kyushu University, Kasuga, Fukuoka, Japan
| | - François-Didier Boyer
- Université Paris-Saclay, CNRS, Institut de Chimie des Substances Naturelles, Gif-sur-Yvette, France
| | - Trevor L. Wang
- John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Michael Udvardi
- Noble Research Institute, Ardmore, Oklahoma, United States of America
| | - Mark T. Waters
- School of Molecular Sciences, The University of Western Australia, Perth, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, The University of Western Australia, Perth, Australia
| | - Caroline Gutjahr
- LMU Munich, Faculty of Biology, Genetics, Biocenter Martinsried, Martinsried, Germany
- Technical University of Munich (TUM), TUM School of Life Sciences, Plant Genetics, Freising, Germany
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Matthus E, Doddrell NH, Guillaume G, Mohammad-Sidik AB, Wilkins KA, Swarbreck SM, Davies JM. Phosphate Deprivation Can Impair Mechano-Stimulated Cytosolic Free Calcium Elevation in Arabidopsis Roots. PLANTS 2020; 9:plants9091205. [PMID: 32942534 PMCID: PMC7570281 DOI: 10.3390/plants9091205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/08/2020] [Accepted: 09/11/2020] [Indexed: 12/28/2022]
Abstract
The root tip responds to mechanical stimulation with a transient increase in cytosolic free calcium as a possible second messenger. Although the root tip will grow through a heterogeneous soil nutrient supply, little is known of the consequence of nutrient deprivation for such signalling. Here, the effect of inorganic phosphate deprivation on the root’s mechano-stimulated cytosolic free calcium increase is investigated. Arabidopsisthaliana (cytosolically expressing aequorin as a bioluminescent free calcium reporter) is grown in zero or full phosphate conditions, then roots or root tips are mechanically stimulated. Plants also are grown vertically on a solid medium so their root skewing angle (deviation from vertical) can be determined as an output of mechanical stimulation. Phosphate starvation results in significantly impaired cytosolic free calcium elevation in both root tips and whole excised roots. Phosphate-starved roots sustain a significantly lower root skewing angle than phosphate-replete roots. These results suggest that phosphate starvation causes a dampening of the root mechano-signalling system that could have consequences for growth in hardened, compacted soils.
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Affiliation(s)
- Elsa Matthus
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
| | - Nicholas H. Doddrell
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
- NIAB EMR, New Road, East Malling ME19 6BJ, UK
| | - Gaëtan Guillaume
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
| | - Amirah B. Mohammad-Sidik
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
| | - Katie A. Wilkins
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
| | - Stéphanie M. Swarbreck
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
- The John Bingham Laboratory, NIAB, 93 Lawrence Weaver Road, Cambridge CB3 0LE, UK
| | - Julia M. Davies
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK; (E.M.); (N.H.D.); (G.G.); (A.B.M.-S.); (K.A.W.); (S.M.S.)
- Correspondence:
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38
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Swarbreck SM, Mohammad-Sidik A, Davies JM. Common Components of the Strigolactone and Karrikin Signaling Pathways Suppress Root Branching in Arabidopsis. PLANT PHYSIOLOGY 2020; 184:18-22. [PMID: 32690756 PMCID: PMC7479902 DOI: 10.1104/pp.19.00687] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 07/08/2020] [Indexed: 05/26/2023]
Abstract
Adventitious and lateral root development is regulated by elements involved in both the strigolactone and karrikin perception pathways.
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Affiliation(s)
- Stéphanie M Swarbreck
- Department of Plant Sciences, University of Cambridge, Downing Site, Cambridge, United Kingdom CB2 3EA
| | - Amirah Mohammad-Sidik
- Department of Plant Sciences, University of Cambridge, Downing Site, Cambridge, United Kingdom CB2 3EA
| | - Julia M Davies
- Department of Plant Sciences, University of Cambridge, Downing Site, Cambridge, United Kingdom CB2 3EA
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39
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Zheng J, Hong K, Zeng L, Wang L, Kang S, Qu M, Dai J, Zou L, Zhu L, Tang Z, Meng X, Wang B, Hu J, Zeng D, Zhao Y, Cui P, Wang Q, Qian Q, Wang Y, Li J, Xiong G. Karrikin Signaling Acts Parallel to and Additively with Strigolactone Signaling to Regulate Rice Mesocotyl Elongation in Darkness. THE PLANT CELL 2020; 32:2780-2805. [PMID: 32665307 PMCID: PMC7474294 DOI: 10.1105/tpc.20.00123] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/02/2020] [Accepted: 07/09/2020] [Indexed: 05/18/2023]
Abstract
Seedling emergence in monocots depends mainly on mesocotyl elongation, requiring coordination between developmental signals and environmental stimuli. Strigolactones (SLs) and karrikins are butenolide compounds that regulate various developmental processes; both are able to negatively regulate rice (Oryza sativa) mesocotyl elongation in the dark. Here, we report that a karrikin signaling complex, DWARF14-LIKE (D14L)-DWARF3 (D3)-O. sativa SUPPRESSOR OF MAX2 1 (OsSMAX1) mediates the regulation of rice mesocotyl elongation in the dark. We demonstrate that D14L recognizes the karrikin signal and recruits the SCFD3 ubiquitin ligase for the ubiquitination and degradation of OsSMAX1, mirroring the SL-induced and D14- and D3-dependent ubiquitination and degradation of D53. Overexpression of OsSMAX1 promoted mesocotyl elongation in the dark, whereas knockout of OsSMAX1 suppressed the elongated-mesocotyl phenotypes of d14l and d3 OsSMAX1 localizes to the nucleus and interacts with TOPLESS-RELATED PROTEINs, regulating downstream gene expression. Moreover, we showed that the GR24 enantiomers GR245DS and GR24 ent-5DS specifically inhibit mesocotyl elongation and regulate downstream gene expression in a D14- and D14L-dependent manner, respectively. Our work revealed that karrikin and SL signaling play parallel and additive roles in modulating downstream gene expression and negatively regulating mesocotyl elongation in the dark.
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Affiliation(s)
- Jianshu Zheng
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Kai Hong
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Longjun Zeng
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
- Plant Phenomics Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Lei Wang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Shujing Kang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
- College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Minghao Qu
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Jiarong Dai
- Plant Phenomics Research Center, Nanjing Agricultural University, Nanjing, 210095, China
- College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Linyuan Zou
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Lixin Zhu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China
| | - Zhanpeng Tang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Xiangbing Meng
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
| | - Bing Wang
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jiang Hu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China
| | - Dali Zeng
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China
| | - Yonghui Zhao
- Plant Phenomics Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Peng Cui
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Quan Wang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
| | - Qian Qian
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310006, China
| | - Yonghong Wang
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100039, China
- College of Life Sciences, Shandong Agricultural University, Taian, 271018, China
| | - Jiayang Li
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100039, China
| | - Guosheng Xiong
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
- Plant Phenomics Research Center, Nanjing Agricultural University, Nanjing, 210095, China
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Khosla A, Morffy N, Li Q, Faure L, Chang SH, Yao J, Zheng J, Cai ML, Stanga J, Flematti GR, Waters MT, Nelson DC. Structure-Function Analysis of SMAX1 Reveals Domains That Mediate Its Karrikin-Induced Proteolysis and Interaction with the Receptor KAI2. THE PLANT CELL 2020; 32:2639-2659. [PMID: 32434855 PMCID: PMC7401016 DOI: 10.1105/tpc.19.00752] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 04/13/2020] [Accepted: 05/14/2020] [Indexed: 05/18/2023]
Abstract
Karrikins (KARs) are butenolides found in smoke that can influence germination and seedling development of many plants. The KAR signaling mechanism is hypothesized to be very similar to that of the plant hormone strigolactone (SL). Both pathways require the F-box protein MORE AXILLARY GROWTH2 (MAX2), and other core signaling components have shared ancestry. Putatively, KAR activates the receptor KARRIKIN INSENSITIVE2 (KAI2), triggering its association with the E3 ubiquitin ligase complex SCFMAX2 and downstream targets SUPPRESSOR OF MAX2 1 (SMAX1) and SMAX1-LIKE2 (SMXL2). Polyubiquitination and proteolysis of SMAX1 and SMXL2 then enable growth responses to KAR. However, many of the assumptions of this model have not been demonstrated. Therefore, we investigated the posttranslational regulation of SMAX1 from the model plant Arabidopsis (Arabidopsis thaliana). We find evidence that SMAX1 is degraded by KAI2-SCFMAX2 but is also subject to MAX2-independent turnover. We identify SMAX1 domains that are responsible for its nuclear localization, KAR-induced degradation, association with KAI2, and ability to interact with other SMXL proteins. KAI2 undergoes MAX2-independent degradation after KAR treatment, which we propose results from its association with SMAX1 and SMXL2. Finally, we discover an SMXL domain that mediates receptor-target interaction preferences in KAR and SL signaling, laying the foundation for understanding how these highly similar pathways evolved to fulfill different roles.
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Affiliation(s)
- Aashima Khosla
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - Nicholas Morffy
- Department of Genetics, University of Georgia, Athens, Georgia 30602
| | - Qingtian Li
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - Lionel Faure
- Department of Genetics, University of Georgia, Athens, Georgia 30602
- Department of Biology, Texas Woman's University, Denton, Texas 76204
| | - Sun Hyun Chang
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - Jiaren Yao
- School of Molecular Sciences, University of Western Australia Perth, Crawley, Western Australia 6009, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia Perth, Crawley, Western Australia 6009, Australia
| | - Jiameng Zheng
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - Mei L Cai
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
| | - John Stanga
- Department of Genetics, University of Georgia, Athens, Georgia 30602
- Department of Biology, Mercer University, Macon, Georgia 31207
| | - Gavin R Flematti
- School of Molecular Sciences, University of Western Australia Perth, Crawley, Western Australia 6009, Australia
| | - Mark T Waters
- School of Molecular Sciences, University of Western Australia Perth, Crawley, Western Australia 6009, Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia Perth, Crawley, Western Australia 6009, Australia
| | - David C Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521
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41
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Li W, Nguyen KH, Chu HD, Watanabe Y, Osakabe Y, Sato M, Toyooka K, Seo M, Tian L, Tian C, Yamaguchi S, Tanaka M, Seki M, Tran LSP. Comparative functional analyses of DWARF14 and KARRIKIN INSENSITIVE 2 in drought adaptation of Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:111-127. [PMID: 32022953 DOI: 10.1111/tpj.14712] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 01/13/2020] [Accepted: 01/29/2020] [Indexed: 05/23/2023]
Abstract
Functional analyses of various strigolactone-deficient mutants have demonstrated that strigolactones enhance drought resistance; however, the mechanistic involvement of the strigolactone receptor DWARF14 (D14) in this trait remains elusive. In this study, loss-of-function analysis of the D14 gene in Arabidopsis thaliana revealed that d14 mutant plants were more drought-susceptible than wild-type plants, which was associated with their larger stomatal aperture, slower abscisic acid (ABA)-mediated stomatal closure, lower anthocyanin content and delayed senescence under drought stress. Transcriptome analysis revealed a consistent alteration in the expression levels of many genes related to the observed physiological and biochemical changes in d14 plants when compared with the wild type under normal and dehydration conditions. A comparative drought resistance assay confirmed that D14 plays a less critical role in Arabidopsis drought resistance than its paralog karrikin receptor KARRIKIN INSENSITIVE 2 (KAI2). In-depth comparative analyses of the single mutants d14 and kai2 and the double mutant d14 kai2, in relation to various drought resistance-associated mechanisms, revealed that D14 and KAI2 exhibited a similar effect on stomatal closure. On the other hand, D14 had a lesser role in the maintenance of cell membrane integrity, leaf cuticle structure and ABA-induced leaf senescence, but a greater role in drought-induced anthocyanin biosynthesis, than KAI2. Interestingly, a possible additive relationship between D14 and KAI2 could be observed in regulating cell membrane integrity and leaf cuticle development. In addition, our findings also suggest the existence of a complex interaction between the D14 and ABA signaling pathways in the adaptation of Arabidopsis to drought.
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Affiliation(s)
- Weiqiang Li
- Department of Biology, Institute of Plant Stress Biology, State Key Laboratory of Cotton Biology, Henan University, 85 Minglun Street, Kaifeng, 475001, China
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Kien Huu Nguyen
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
- National Key Laboratory for Plant Cell Biotechnology, Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham-Van-Dong Str., Hanoi, 100000, Vietnam
| | - Ha Duc Chu
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
- National Key Laboratory for Plant Cell Biotechnology, Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham-Van-Dong Str., Hanoi, 100000, Vietnam
| | - Yasuko Watanabe
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Yuriko Osakabe
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8513, Japan
| | - Mayuko Sato
- Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Kiminori Toyooka
- Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Mitsunori Seo
- Dormancy and Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
| | - Lei Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China
| | - Shinjiro Yamaguchi
- Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan
- Institute for Chemical Research, Kyoto University, Uji, 611-0011, Japan
| | - Maho Tanaka
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, Wako, 351-0198, Japan
| | - Motoaki Seki
- Plant Genomic Network Research Team, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
- Plant Epigenome Regulation Laboratory, RIKEN Cluster for Pioneering Research, Wako, 351-0198, Japan
| | - Lam-Son Phan Tran
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan
- Institute of Research and Development, Duy Tan University, Da Nang, 550000, Vietnam
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42
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Wang L, Xu Q, Yu H, Ma H, Li X, Yang J, Chu J, Xie Q, Wang Y, Smith SM, Li J, Xiong G, Wang B. Strigolactone and Karrikin Signaling Pathways Elicit Ubiquitination and Proteolysis of SMXL2 to Regulate Hypocotyl Elongation in Arabidopsis. THE PLANT CELL 2020; 32:2251-2270. [PMID: 32358074 PMCID: PMC7346549 DOI: 10.1105/tpc.20.00140] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/10/2020] [Accepted: 04/28/2020] [Indexed: 05/18/2023]
Abstract
Strigolactones (SLs) and karrikins (KARs) are related butenolide signaling molecules that control plant development. In Arabidopsis (Arabidopsis thaliana), they are recognized separately by two closely related receptors but use the same F-box protein MORE AXILLARY GROWTH2 (MAX2) for signal transduction, targeting different members of the SMAX1-LIKE (SMXL) family of transcriptional repressors for degradation. Both signals inhibit hypocotyl elongation in seedlings, raising the question of whether signaling is convergent or parallel. Here, we show that synthetic SL analog GR244DO enhanced the interaction between the SL receptor DWARF14 (D14) and SMXL2, while the KAR surrogate GR24 ent-5DS induced association of the KAR receptor KARRIKIN INSENSITIVE2 (KAI2) with SMAX1 and SMXL2. Both signals trigger polyubiquitination and degradation of SMXL2, with GR244DO dependent on D14 and GR24 ent-5DS dependent mainly on KAI2. SMXL2 is critical for hypocotyl responses to GR244DO and functions redundantly with SMAX1 in hypocotyl response to GR24 ent-5DS Furthermore, GR244DO induced response of D14-LIKE2 and KAR-UP F-BOX1 through SMXL2, whereas GR24 ent-5DS induced expression of these genes via both SMAX1 and SMXL2. These findings demonstrate that both SLs and KARs could trigger polyubiquitination and degradation of SMXL2, thus uncovering an unexpected but important convergent pathway in SL- and KAR-regulated gene expression and hypocotyl elongation.
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Affiliation(s)
- Lei Wang
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Qian Xu
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Hong Yu
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Haiyan Ma
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaoqiang Li
- CAS Key Laboratory of Energy Regulation, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jun Yang
- CAS Key Laboratory of Energy Regulation, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jinfang Chu
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Qi Xie
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Yonghong Wang
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100039, China
- College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China
| | - Steven M Smith
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
- School of Natural Sciences, University of Tasmania, Hobart 7001, Australia
| | - Jiayang Li
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Guosheng Xiong
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
- Plant Phenomics Research Center, Nanjing Agricultural University, Nanjing 210095, China
| | - Bing Wang
- State Key Laboratory of Plant Genomics, and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101, China
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43
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Khosla A, Rodriguez‐Furlan C, Kapoor S, Van Norman JM, Nelson DC. A series of dual-reporter vectors for ratiometric analysis of protein abundance in plants. PLANT DIRECT 2020; 4:e00231. [PMID: 32582876 PMCID: PMC7306620 DOI: 10.1002/pld3.231] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 05/10/2020] [Accepted: 05/13/2020] [Indexed: 05/06/2023]
Abstract
Ratiometric reporter systems enable comparisons of the abundance of a protein of interest, or "target," relative to a reference protein. Both proteins are encoded on a single transcript but are separated during translation. This arrangement bypasses the potential for discordant expression that can arise when the target and reference proteins are encoded by separate genes. We generated a set of 18 Gateway-compatible vectors termed pRATIO that combine a variety of promoters, fluorescent, and bioluminescent reporters, and 2A "self-cleaving" peptides. These constructs are easily modified to produce additional combinations or introduce new reporter proteins. We found that mScarlet-I provides the best signal-to-noise ratio among several fluorescent reporter proteins during transient expression experiments in Nicotiana benthamiana. Firefly and Gaussia luciferase also produce high signal-to-noise in N. benthamiana. As proof of concept, we used this system to investigate whether degradation of the receptor KAI2 after karrikin treatment is influenced by its subcellular localization. KAI2 is normally found in the cytoplasm and the nucleus of plant cells. In N. benthamiana, karrikin-induced degradation of KAI2 was only observed when it was retained in the nucleus. These vectors are tools to easily monitor in vivo the abundance of a protein that is transiently expressed in plants, and will be particularly useful for investigating protein turnover in response to different stimuli.
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Affiliation(s)
- Aashima Khosla
- Department of Botany and Plant SciencesUniversity of CaliforniaRiversideCAUSA
| | | | - Suraj Kapoor
- Department of GeneticsUniversity of GeorgiaAthensGAUSA
| | | | - David C. Nelson
- Department of Botany and Plant SciencesUniversity of CaliforniaRiversideCAUSA
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Choi J, Lee T, Cho J, Servante EK, Pucker B, Summers W, Bowden S, Rahimi M, An K, An G, Bouwmeester HJ, Wallington EJ, Oldroyd G, Paszkowski U. The negative regulator SMAX1 controls mycorrhizal symbiosis and strigolactone biosynthesis in rice. Nat Commun 2020; 11:2114. [PMID: 32355217 PMCID: PMC7193599 DOI: 10.1038/s41467-020-16021-1] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 04/08/2020] [Indexed: 12/17/2022] Open
Abstract
Most plants associate with beneficial arbuscular mycorrhizal (AM) fungi that facilitate soil nutrient acquisition. Prior to contact, partner recognition triggers reciprocal genetic remodelling to enable colonisation. The plant Dwarf14-Like (D14L) receptor conditions pre-symbiotic perception of AM fungi, and also detects the smoke constituent karrikin. D14L-dependent signalling mechanisms, underpinning AM symbiosis are unknown. Here, we present the identification of a negative regulator from rice, which operates downstream of the D14L receptor, corresponding to the homologue of the Arabidopsis thaliana Suppressor of MAX2-1 (AtSMAX1) that functions in karrikin signalling. We demonstrate that rice SMAX1 is a suppressor of AM symbiosis, negatively regulating fungal colonisation and transcription of crucial signalling components and conserved symbiosis genes. Similarly, rice SMAX1 negatively controls strigolactone biosynthesis, demonstrating an unexpected crosstalk between the strigolactone and karrikin signalling pathways. We conclude that removal of SMAX1, resulting from D14L signalling activation, de-represses essential symbiotic programmes and increases strigolactone hormone production. Signaling via the D14L karrikin receptor conditions rice roots for association with arbuscular mycorrhizal fungi. Here, Choi et al. show that SMAX1, a rice homolog of an Arabidopsis repressor of karrikin signaling, acts downstream of D14L to suppress mycorrhizal symbiosis and strigolactone biosynthesis.
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Affiliation(s)
- Jeongmin Choi
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.
| | - Tak Lee
- Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, CB2 1LR, UK
| | - Jungnam Cho
- Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, CB2 1LR, UK.,CAS-JIC Centre of Excellence for Plant and Microbial Science, 200032, Shanghai, China
| | - Emily K Servante
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - Boas Pucker
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.,Center for Biotechnology, Bielefeld University, Sequenz 1, 33615, Bielefeld, Germany
| | - William Summers
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - Sarah Bowden
- The John Bingham Laboratory, NIAB, Huntingdon Road, Cambridge, CB3 0LE, UK
| | - Mehran Rahimi
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Kyungsook An
- Crop Biotech Institute, Kyung Hee University, Yongjin-si, 446-701, South Korea
| | - Gynheung An
- Crop Biotech Institute, Kyung Hee University, Yongjin-si, 446-701, South Korea
| | - Harro J Bouwmeester
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Emma J Wallington
- The John Bingham Laboratory, NIAB, Huntingdon Road, Cambridge, CB3 0LE, UK
| | - Giles Oldroyd
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.,Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, CB2 1LR, UK
| | - Uta Paszkowski
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK.
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Abstract
This review focuses on the evolution of plant hormone signaling pathways. Like the chemical nature of the hormones themselves, the signaling pathways are diverse. Therefore, we focus on a group of hormones whose primary perception mechanism involves an Skp1/Cullin/F-box-type ubiquitin ligase: auxin, jasmonic acid, gibberellic acid, and strigolactone. We begin with a comparison of the core signaling pathways of these four hormones, which have been established through studies conducted in model organisms in the Angiosperms. With the advent of next-generation sequencing and advanced tools for genetic manipulation, the door to understanding the origins of hormone signaling mechanisms in plants beyond these few model systems has opened. For example, in-depth phylogenetic analyses of hormone signaling components are now being complemented by genetic studies in early diverging land plants. Here we discuss recent investigations of how basal land plants make and sense hormones. Finally, we propose connections between the emergence of hormone signaling complexity and major developmental transitions in plant evolution.
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Affiliation(s)
- Miguel A Blázquez
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, 46022 Valencia, Spain;
| | - David C Nelson
- Department of Botany and Plant Sciences, University of California, Riverside, California 92521, USA;
| | - Dolf Weijers
- Laboratory of Biochemistry, Wageningen University, 6708WE Wageningen, The Netherlands;
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Li W, Nguyen KH, Tran CD, Watanabe Y, Tian C, Yin X, Li K, Yang Y, Guo J, Miao Y, Yamaguchi S, Tran LSP. Negative Roles of Strigolactone-Related SMXL6, 7 and 8 Proteins in Drought Resistance in Arabidopsis. Biomolecules 2020; 10:biom10040607. [PMID: 32295207 PMCID: PMC7226073 DOI: 10.3390/biom10040607] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/04/2020] [Accepted: 04/09/2020] [Indexed: 12/22/2022] Open
Abstract
Previous investigations have shown that the SUPPRESSORS OF MAX2 1-LIKE6, 7 and 8 (SMXL6, 7 and 8) proteins redundantly repress strigolactone (SL) signaling in plant growth and development. Recently, a growing body of evidence indicated that SLs positively regulate plant drought resistance through functional analyses of genes involved in SL biosynthesis and positive regulation of SL signaling. However, the functions of the SL-signaling negative regulators SMXL6, 7 and 8 in drought resistance and the associated mechanisms remain elusive. To reveal the functions of these SMXL proteins, we analyzed the drought-resistant phenotype of the triple smxl6,7,8 mutant plants and studied several drought resistance-related traits. Our results showed that the smxl6,7,8 mutant plants were more resistant to drought than wild-type plants. Physiological investigations indicated that the smxl6,7,8 mutant plants exhibited higher leaf surface temperature, reduced cuticle permeability, as well as decreases in drought-induced water loss and cell membrane damage in comparison with wild-type plants. Additionally, smxl6,7,8 mutant plants displayed an increase in anthocyanin biosynthesis during drought, enhanced detoxification capacity and increased sensitivity to abscisic acid in cotyledon opening and growth inhibition assays. A good correlation between the expression levels of some relevant genes and the examined physiological and biochemical traits was observed. Our findings together indicate that the SMXL6, 7 and 8 act as negative regulators of drought resistance, and that disruption of these SMXL genes in crops may provide a novel way to improve their drought resistance.
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Affiliation(s)
- Weiqiang Li
- Institute of Plant Stress Biology, State Key Laboratory of Cotton Biology, Department of Biology, Henan University, 85 Minglun Street, Kaifeng 475001, China; or (K.L.); (Y.Y.); (J.G.); (Y.M.)
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan; (C.D.T.); (Y.W.)
| | - Kien Huu Nguyen
- Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham Van Dong Str., Hanoi 100000, Vietnam;
| | - Cuong Duy Tran
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan; (C.D.T.); (Y.W.)
- Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham Van Dong Str., Hanoi 100000, Vietnam;
| | - Yasuko Watanabe
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan; (C.D.T.); (Y.W.)
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China;
| | - Xiaojian Yin
- State Key Laboratory of Natural Medicines, Department of Pharmacognosy, Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing 210009, China;
| | - Kun Li
- Institute of Plant Stress Biology, State Key Laboratory of Cotton Biology, Department of Biology, Henan University, 85 Minglun Street, Kaifeng 475001, China; or (K.L.); (Y.Y.); (J.G.); (Y.M.)
| | - Yong Yang
- Institute of Plant Stress Biology, State Key Laboratory of Cotton Biology, Department of Biology, Henan University, 85 Minglun Street, Kaifeng 475001, China; or (K.L.); (Y.Y.); (J.G.); (Y.M.)
| | - Jinggong Guo
- Institute of Plant Stress Biology, State Key Laboratory of Cotton Biology, Department of Biology, Henan University, 85 Minglun Street, Kaifeng 475001, China; or (K.L.); (Y.Y.); (J.G.); (Y.M.)
| | - Yuchen Miao
- Institute of Plant Stress Biology, State Key Laboratory of Cotton Biology, Department of Biology, Henan University, 85 Minglun Street, Kaifeng 475001, China; or (K.L.); (Y.Y.); (J.G.); (Y.M.)
| | - Shinjiro Yamaguchi
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan;
| | - Lam-Son Phan Tran
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22, Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan; (C.D.T.); (Y.W.)
- Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang 550000, Vietnam
- Correspondence: or
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Yao J, Waters MT. Perception of karrikins by plants: a continuing enigma. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1774-1781. [PMID: 31836893 PMCID: PMC7242065 DOI: 10.1093/jxb/erz548] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/09/2019] [Indexed: 05/28/2023]
Abstract
Karrikins are small butenolide molecules with the capacity to promote germination and enhance seedling establishment. Generated abiotically from partial combustion of vegetation, karrikins are comparatively rare in the environment, but studying their mode of action has been most informative in revealing a new regulatory pathway for plant development that uses the karrikin perception machinery. Recent studies suggest that the karrikin receptor protein KAI2 and downstream transcriptional co-repressors in the SMXL family influence seed germination, seedling photomorphogenesis, root morphology, and responses to abiotic stress such as drought. Based on taxonomic distribution, this pathway is ubiquitous and likely to be evolutionarily ancient, originating prior to land plants. However, we still do not have a good grasp on how karrikins actually activate the receptor protein, and we have yet to discover the assumed endogenous ligand for KAI2 that karrikins are thought to mimic. This review covers recent progress in this field, as well as current gaps in our knowledge.
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Affiliation(s)
- Jiaren Yao
- School of Molecular Sciences, The University of Western Australia, Perth, WA, Australia
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Abd-Hamid NA, Ahmad-Fauzi MI, Zainal Z, Ismail I. Diverse and dynamic roles of F-box proteins in plant biology. PLANTA 2020; 251:68. [PMID: 32072251 DOI: 10.1007/s00425-020-03356-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 02/05/2020] [Indexed: 05/23/2023]
Abstract
The SCF complex is a widely studied multi-subunit ring E3 ubiquitin ligase that tags targeted proteins with ubiquitin for protein degradation by the ubiquitin 26S-proteasome system (UPS). The UPS is an important system that generally keeps cellular events tightly regulated by purging misfolded or damaged proteins and selectively degrading important regulatory proteins. The specificity of this post-translational regulation is controlled by F-box proteins (FBPs) via selective recognition of a protein-protein interaction motif at the C-terminal domain. Hence, FBPs are pivotal proteins in determining the plant response in multiple scenarios. It is not surprising that the FBP family is one of the largest protein families in the plant kingdom. In this review, the roles of FBPs, specifically in plants, are compiled to provide insights into their involvement in secondary metabolites, plant stresses, phytohormone signalling, plant developmental processes and miRNA biogenesis.
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Affiliation(s)
- Nur-Athirah Abd-Hamid
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia
| | - Muhammad-Izzat Ahmad-Fauzi
- Department of Biological Sciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia
| | - Zamri Zainal
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia
- Department of Biological Sciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia
| | - Ismanizan Ismail
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia.
- Department of Biological Sciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia.
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49
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Machin DC, Hamon-Josse M, Bennett T. Fellowship of the rings: a saga of strigolactones and other small signals. THE NEW PHYTOLOGIST 2020; 225:621-636. [PMID: 31442309 DOI: 10.1111/nph.16135] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 08/08/2019] [Indexed: 05/25/2023]
Abstract
Strigolactones are an important class of plant signalling molecule with both external rhizospheric and internal hormonal functions in flowering plants. The past decade has seen staggering progress in strigolactone biology, permitting highly detailed understanding of their signalling, synthesis and biological roles - or so it seems. However, phylogenetic analyses show that strigolactone signalling mediated by the D14-SCFMAX2 -SMXL7 complex is only one of a number of closely related signalling pathways, and is much less ubiquitous in land plants than might be expected. The existence of closely related pathways, such as the KAI2-SMAX1 module, challenges many of our assumptions about strigolactones, and in particular emphasises how little we understand about the specificity of strigolactone signalling with respect to related signalling pathways. In this review, we examine recent advances in strigolactone signalling, taking a holistic evolutionary view to identify the ambiguities and uncertainties in our understanding. We highlight that while we now have highly detailed molecular models for the core mechanism of D14-SMXL7 signalling, we still do not understand the ligand specificity of D14, the specificity of its interaction with SMXL7, nor the specificity of SMXL7 function. Our analysis therefore identifies key areas requiring further study.
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Affiliation(s)
- Darren C Machin
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Maxime Hamon-Josse
- 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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50
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Califar B, Sng NJ, Zupanska A, Paul AL, Ferl RJ. Root Skewing-Associated Genes Impact the Spaceflight Response of Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2020; 11:239. [PMID: 32194611 PMCID: PMC7064724 DOI: 10.3389/fpls.2020.00239] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 02/17/2020] [Indexed: 05/03/2023]
Abstract
The observation that plant roots skew in microgravity recently refuted the long-held conviction that skewing was a gravity-dependent phenomenon. Further, spaceflight root skewing suggests that specific root morphologies and cell wall remodeling systems may be important aspects of spaceflight physiological adaptation. However, connections between skewing, cell wall modification and spaceflight physiology are currently based on inferences rather than direct tests. Therefore, the Advanced Plant Experiments-03-2 (APEX-03-2) spaceflight study was designed to elucidate the contribution of two skewing- and cell wall-associated genes in Arabidopsis to root behavior and gene expression patterns in spaceflight, to assess whether interruptions of different skewing pathways affect the overall spaceflight-associated process. SPIRAL1 is a skewing-related protein implicated in directional cell expansion, and functions by regulating cortical microtubule dynamics. SKU5 is skewing-related glycosylphosphatidylinositol-anchored protein of the plasma membrane and cell wall implicated in stress response signaling. These two genes function in different cellular pathways that affect skewing on the Earth, and enable a test of the relevance of skewing pathways to spaceflight physiological adaptation. In this study, both sku5 and spr1 mutants showed different skewing behavior and markedly different patterns of gene expression in the spaceflight environment. The spr1 mutant showed fewer differentially expressed genes than its Col-0 wild-type, whereas sku5 showed considerably more than its WS wild-type. Developmental age played a substantial role in spaceflight acclimation in all genotypes, but particularly in sku5 plants, where spaceflight 4d seedlings had almost 10-times as many highly differentially expressed genes as the 8d seedlings. These differences demonstrated that the two skewing pathways represented by SKU5 and SPR1 have unique and opposite contributions to physiological adaptation to spaceflight. The spr1 response is less intense than wild type, suggesting that the loss of SPR1 positively impacts spaceflight adaptation. Conversely, the intensity of the sku5 responses suggests that the loss of SKU5 initiates a much more complex, deeper and more stress related response to spaceflight. This suggests that proper SKU5 function is important to spaceflight adaptation.
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Affiliation(s)
- Brandon Califar
- Horticultural Sciences, University of Florida, Gainesville, FL, United States
- The Genetics Institute, University of Florida, Gainesville, FL, United States
- Program in Genetics and Genomics, University of Florida, Gainesville, FL, United States
| | - Natasha J. Sng
- Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | - Agata Zupanska
- Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | - Anna-Lisa Paul
- Horticultural Sciences, University of Florida, Gainesville, FL, United States
- The Genetics Institute, University of Florida, Gainesville, FL, United States
- Program in Genetics and Genomics, University of Florida, Gainesville, FL, United States
- Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL, United States
- Interdisciplinary Center for Biotechnology and Research, University of Florida, Gainesville, FL, United States
- *Correspondence: Anna-Lisa Paul,
| | - Robert J. Ferl
- Horticultural Sciences, University of Florida, Gainesville, FL, United States
- The Genetics Institute, University of Florida, Gainesville, FL, United States
- Program in Genetics and Genomics, University of Florida, Gainesville, FL, United States
- Program in Plant Molecular and Cellular Biology, University of Florida, Gainesville, FL, United States
- Robert J. Ferl,
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