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Li J, Sheng Y, Xu H, Li Q, Lin X, Zhou Y, Zhao Y, Song X, Wang J. Transcriptome and hormone metabolome reveal the mechanism of stem bending in water lily ( Nymphaea tetragona) cut-flowers. FRONTIERS IN PLANT SCIENCE 2023; 14:1195389. [PMID: 37746018 PMCID: PMC10515221 DOI: 10.3389/fpls.2023.1195389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 08/24/2023] [Indexed: 09/26/2023]
Abstract
Water lilies are popular ornamental cut-flowers with significant economic and cultural value. However, stem bending affects the preservation of cut-flowers during their vase life. To gain further insights into the molecular mechanisms of stem bending, transcriptome profiling, hormone measurement, and morphological analysis were performed using the stems of the 'Blue Bird' water lily. Transcriptome analysis revealed that 607 differentially expressed genes (DEGs) were associated with the dorsal and ventral stems of the water lily, of which 247 were up-regulated and 360 were down-regulated. Significant differences in genes associated with plant hormones, calcium ions, glucose metabolism, and photosynthesis pathways genes involved in the dorsal and ventral areas of the curved stem. In particular, DEGs were associated with the hormone synthesis, gravity response, starch granules, Ca2+ ions, and photosynthesis. The results of qRT-PCR were consistent with that of the transcriptome sequence analysis. A total of 12 hormones were detected, of which abscisic acid, indole-3-carboxaldehyde, indole-3-carboxaldehyde and jasmonic acid were significantly differentially expressed in the dorsal and ventral stems, and were significantly higher in the dorsal stem than in the ventral stem. The cell morphology in the dorsal and ventral areas of the curved stem clearly changed during vase life. The direction of starch granule settlement was consistent with the bending direction of the water lily stem, as well as the direction of gravity. In conclusion, stem bending in water lily cut-flowers is regulated by multiple factors and genes. This study provides an important theoretical basis for understanding the complex regulatory mechanism of water lily stem bending.
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Affiliation(s)
- Jie Li
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Yuhui Sheng
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
- College of Agricultural, Hengxing University, Qingdao, Shandong, China
| | - Huixian Xu
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Qinxue Li
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Xiuya Lin
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Yang Zhou
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Ying Zhao
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Xiqiang Song
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
| | - Jian Wang
- Key Laboratory of Genetics and Germplasm Innovation of Tropical Forest Trees and Ornamental Plants, Ministry of Education, College of Forestry, Hainan University, Haikou, Hainan, China
- Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan, Haikou, Hainan, China
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Chen LN, Dou PT, Chen YK, Yang HQ. Mutant IAA21 genes from Dendrocalamus sinicus Chia et J. L. Sun inhibit stem and root growth in transgenic tobacco by interacting with ARF5. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 201:107827. [PMID: 37329689 DOI: 10.1016/j.plaphy.2023.107827] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 05/22/2023] [Accepted: 06/07/2023] [Indexed: 06/19/2023]
Abstract
Woody bamboos are important resource of industrial fibres. Auxin signaling plays a key role in multiple plant developmental processes, as yet the role of auxin/indole acetic acid (Aux/IAA) in culm development of woody bamboos has not been previously characterized. Dendrocalamus sinicus Chia et J. L. Sun is the largest woody bamboo documented in the world. Here, we identified two alleles of DsIAA21 gene (sIAA21 and bIAA21) from the straight- and bent-culm variants of D. sinicus, respectively, and studied how the domains I, i, and II of DsIAA21 affect the gene transcriptional repression. The results showed that bIAA21 expression was rapidly induced by exogenous auxin in D. sinicus. In transgenic tobacco, sIAA21 and bIAA21 mutated in domains i, and II significantly regulated plant architecture and root development. Stem cross sections revealed that parenchyma cells were smaller in transgenic plants than that in wild type plants. Domain i mutation changed the leucine and proline at position 45 to proline and leucine (siaa21L45P and biaa21P45L) strongly repressed cell expansion and root elongation by reducing the gravitropic response. Substitution of isoleucine with valine in domain II of the full length DsIAA21 resulted in dwarf stature in transgenic tobacco plants. Furthermore, the DsIAA21 interacted with auxin response factor 5 (ARF5) in transgenic tobacco plants, suggesting that DsIAA21 might inhibit stem and root elongation via interacting with ARF5. Taken together, our data indicated that DsIAA21 was a negative regulator of plant development and suggested that amino acid differences in domain i of sIAA21 versus bIAA21 affected their response to auxin, and might play a key role in the formation of the bent culm variant in D. sinicus. Our results not only shed a light on the morphogenetic mechanism in D. sinicus, but also provided new insights into versatile function of Aux/IAAs in plants.
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Affiliation(s)
- Ling-Na Chen
- College of Life Science, Xinjiang Normal University, Xinyi Road, Shayibake District, Urumqi, 830054, PR China; Institute of Highland Forest Science, Chinese Academy of Forestry, Bailongsi, Panlong District, Kunming, 650233, PR China
| | - Pei-Tong Dou
- Institute of Highland Forest Science, Chinese Academy of Forestry, Bailongsi, Panlong District, Kunming, 650233, PR China
| | - Yong-Kun Chen
- College of Life Science, Xinjiang Normal University, Xinyi Road, Shayibake District, Urumqi, 830054, PR China; Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology, Xinyi Road, Shayibake District, Urumqi, 830054, PR China
| | - Han-Qi Yang
- Institute of Highland Forest Science, Chinese Academy of Forestry, Bailongsi, Panlong District, Kunming, 650233, PR China.
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3
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Jonsson K, Ma Y, Routier-Kierzkowska AL, Bhalerao RP. Multiple mechanisms behind plant bending. NATURE PLANTS 2023; 9:13-21. [PMID: 36581759 DOI: 10.1038/s41477-022-01310-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 11/08/2022] [Indexed: 06/17/2023]
Abstract
To survive, plants constantly adapt their body shape to their environment. This often involves remarkably rapid bending of their organs such as stems, leaves and roots. Since plant cells are enclosed by stiff cell walls, they use various strategies for bending their organs, which differ from bending mechanisms of soft animal tissues and involve larger physical forces. Here we attempt to summarize and link different viewpoints on bending mechanisms: genes and signalling, mathematical modelling and biomechanics. We argue that quantifying cell growth and physical forces could open a new level in our understanding of bending and resolve some of its paradoxes.
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Affiliation(s)
- Kristoffer Jonsson
- IRBV, Department of Biological Sciences, University of Montreal, Montreal, Quebec, Canada
| | - Yuan Ma
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | | | - Rishikesh P Bhalerao
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden.
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Sampedro-Guerrero J, Vives-Peris V, Gomez-Cadenas A, Clausell-Terol C. Encapsulation Reduces the Deleterious Effects of Salicylic Acid Treatments on Root Growth and Gravitropic Response. Int J Mol Sci 2022; 23:ijms232214019. [PMID: 36430498 PMCID: PMC9696185 DOI: 10.3390/ijms232214019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/06/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022] Open
Abstract
The role of salicylic acid (SA) on plant responses to biotic and abiotic stresses is well documented. However, the mechanism by which exogenous SA protects plants and its interactions with other phytohormones remains elusive. SA effect, both free and encapsulated (using silica and chitosan capsules), on Arabidopsis thaliana development was studied. The effect of SA on roots and rosettes was analysed, determining plant morphological characteristics and hormone endogenous levels. Free SA treatment affected length, growth rate, gravitropic response of roots and rosette size in a dose-dependent manner. This damage was due to the increase of root endogenous SA concentration that led to a reduction in auxin levels. The encapsulation process reduced the deleterious effects of free SA on root and rosette growth and in the gravitropic response. Encapsulation allowed for a controlled release of the SA, reducing the amount of hormone available and the uptake by the plant, mitigating the deleterious effects of the free SA treatment. Although both capsules are suitable as SA carrier matrices, slightly better results were found with chitosan. Encapsulation appears as an attractive technology to deliver phytohormones when crops are cultivated under adverse conditions. Moreover, it can be a good tool to perform basic experiments on phytohormone interactions.
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Affiliation(s)
- Jimmy Sampedro-Guerrero
- Departamento de Biología, Bioquímica y Ciencias Naturales, Universitat Jaume I, 12071 Castellón de la Plana, Spain
| | - Vicente Vives-Peris
- Departamento de Biología, Bioquímica y Ciencias Naturales, Universitat Jaume I, 12071 Castellón de la Plana, Spain
| | - Aurelio Gomez-Cadenas
- Departamento de Biología, Bioquímica y Ciencias Naturales, Universitat Jaume I, 12071 Castellón de la Plana, Spain
- Correspondence: (A.G.-C.); (C.C.-T.)
| | - Carolina Clausell-Terol
- Departamento de Ingeniería Química, Instituto Universitario de Tecnología Cerámica, Universitat Jaume I, 12071 Castellón de la Plana, Spain
- Correspondence: (A.G.-C.); (C.C.-T.)
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5
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Zhou H, Ge H, Chen J, Li X, Yang L, Zhang H, Wang Y. Salicylic Acid Regulates Root Gravitropic Growth via Clathrin-Independent Endocytic Trafficking of PIN2 Auxin Transporter in Arabidopsis thaliana. Int J Mol Sci 2022; 23:ijms23169379. [PMID: 36012641 PMCID: PMC9409447 DOI: 10.3390/ijms23169379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 08/10/2022] [Accepted: 08/13/2022] [Indexed: 11/16/2022] Open
Abstract
The phytohormone salicylic acid (SA) plays a crucial role in plant growth and development. However, the mechanism of high-concentration SA-affected gravitropic response in plant root growth and root hair development is still largely unclear. In this study, wild-type, pin2 mutant and various transgenic fluorescence marker lines of Arabidopsis thaliana were investigated to understand how root growth is affected by high SA treatment under gravitropic stress conditions. We found that exogenous SA application inhibited gravitropic root growth and root hair development in a dose-dependent manner. Further analyses using DIRECT REPEAT5 (DR5)-GFP, auxin sensor DII-VENUS, auxin efflux transporter PIN2-GFP, trans-Golgi network/early endosome (TGN/EE) clathrin-light-chain 2 (CLC2)-mCherry and prevacuolar compartment (PVC) (Rha1)-mCherry transgenic marker lines demonstrated that high SA treatment severely affected auxin accumulation, root-specific PIN2 distribution and PIN2 gene transcription and promoted the vacuolar degradation of PIN2, possibly independent of clathrin-mediated endocytic protein trafficking. Our findings proposed a new underlying mechanism of SA-affected gravitropic root growth and root hair development via the regulation of PIN2 gene transcription and PIN2 protein endocytosis in plants.
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Affiliation(s)
- Houjun Zhou
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai 264025, China
| | - Haiman Ge
- College of Life Sciences, Nanjing University, Nanjing 210093, China
| | - Jiahong Chen
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai 201602, China
| | - Xueqin Li
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai 201602, China
| | - Lei Yang
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai 264025, China
| | - Hongxia Zhang
- The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai 264025, China
- Correspondence: (H.Z.); (Y.W.)
| | - Yuan Wang
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai 201602, China
- Correspondence: (H.Z.); (Y.W.)
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Morales-Quintana L, Ramos P. A Talk between Flavonoids and Hormones to Reorient the Growth of Gymnosperms. Int J Mol Sci 2021; 22:ijms222312630. [PMID: 34884435 PMCID: PMC8657560 DOI: 10.3390/ijms222312630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/20/2021] [Accepted: 11/20/2021] [Indexed: 12/05/2022] Open
Abstract
Plants reorient the growth of affected organs in response to the loss of gravity vector. In trees, this phenomenon has received special attention due to its importance for the forestry industry of conifer species. Sustainable management is a key factor in improving wood quality. It is of paramount importance to understand the molecular and genetic mechanisms underlying wood formation, together with the hormonal and environmental factors that affect wood formation and quality. Hormones are related to the modulation of vertical growth rectification. Many studies have resulted in a model that proposes differential growth in the stem due to unequal auxin and jasmonate allocation. Furthermore, many studies have suggested that in auxin distribution, flavonoids act as molecular controllers. It is well known that flavonoids affect auxin flux, and this is a new area of study to understand the intracellular concentrations and how these compounds can control the gravitropic response. In this review, we focused on different molecular aspects related to the hormonal role in flavonoid homeostasis and what has been done in conifer trees to identify molecular players that could take part during the gravitropic response and reduce low-quality wood formation.
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Affiliation(s)
- Luis Morales-Quintana
- Multidisciplinary Agroindustry Research Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Talca 3467987, Chile
- Correspondence: (L.M.-Q.); (P.R.); Tel.: +56-71-2735-699 (L.M.-Q.); +56-73-2213-501 (P.R.)
| | - Patricio Ramos
- Centro de Investigación de Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca 3460000, Chile
- Centro de Biotecnología de los Recursos Naturales (CenBio), Facultad de Ciencias Agrarias y Forestales, Universidad Católica del Maule, Talca 3460000, Chile
- Centro del Secano, Facultad de Ciencias Agrarias y Forestales, Universidad Católica del Maule, Talca 3460000, Chile
- Correspondence: (L.M.-Q.); (P.R.); Tel.: +56-71-2735-699 (L.M.-Q.); +56-73-2213-501 (P.R.)
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Methods to Quantify Cell Division and Hormone Gradients During Root Tropisms. Methods Mol Biol 2021. [PMID: 34647249 DOI: 10.1007/978-1-0716-1677-2_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Tropisms are growth-based plant directional movements, allowing plants to respond to their living environments. Plant roots have developed various tropic responses, including gravitropism, hydrotropism, chemotropism, and halotropism, in response to the gravity, moisture gradient, nutrient gradient, and salinity gradient, respectively. Revealed mechanisms of several tropic responses suggested that plant hormone gradient and cell division activity play key roles in determining these responses. Approaches to measure cell division and hormone gradients, however, have rarely been applied in root tropic analyses. Here, we describe a number of methods to quantify cell division and hormone gradients during root tropic analysis. These approaches are mainly based on our previous researches on root hydrotropism.
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Vaseva II, Mishev K, Depaepe T, Vassileva V, Van Der Straeten D. The Diverse Salt-Stress Response of Arabidopsis ctr1-1 and ein2-1Ethylene Signaling Mutants Is Linked to Altered Root Auxin Homeostasis. PLANTS 2021; 10:plants10030452. [PMID: 33673672 PMCID: PMC7997360 DOI: 10.3390/plants10030452] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/21/2021] [Accepted: 02/24/2021] [Indexed: 12/19/2022]
Abstract
We explored the interplay between ethylene signals and the auxin pool in roots exposed to high salinity using Arabidopsisthaliana wild-type plants (Col-0), and the ethylene-signaling mutants ctr1-1 (constitutive) and ein2-1 (insensitive). The negative effect of salt stress was less pronounced in ctr1-1 individuals, which was concomitant with augmented auxin signaling both in the ctr1-1 controls and after 100 mM NaCl treatment. The R2D2 auxin sensorallowed mapping this active auxin increase to the root epidermal cells in the late Cell Division (CDZ) and Transition Zone (TZ). In contrast, the ethylene-insensitive ein2-1 plants appeared depleted in active auxins. The involvement of ethylene/auxin crosstalk in the salt stress response was evaluated by introducing auxin reporters for local biosynthesis (pTAR2::GUS) and polar transport (pLAX3::GUS, pAUX1::AUX1-YFP, pPIN1::PIN1-GFP, pPIN2::PIN2-GFP, pPIN3::GUS) in the mutants. The constantly operating ethylene-signaling pathway in ctr1-1 was linked to increased auxin biosynthesis. This was accompanied by a steady expression of the auxin transporters evaluated by qRT-PCR and crosses with the auxin transport reporters. The results imply that the ability of ctr1-1 mutant to tolerate high salinity could be related to the altered ethylene/auxin regulatory loop manifested by a stabilized local auxin biosynthesis and transport.
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Affiliation(s)
- Irina I. Vaseva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria; (K.M.); (V.V.)
- Correspondence: or
| | - Kiril Mishev
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria; (K.M.); (V.V.)
| | - Thomas Depaepe
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckststraat 35, B-9000 Ghent, Belgium; (T.D.); (D.V.D.S.)
| | - Valya Vassileva
- Department of Molecular Biology and Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Bldg. 21, 1113 Sofia, Bulgaria; (K.M.); (V.V.)
| | - Dominique Van Der Straeten
- Laboratory of Functional Plant Biology, Department of Biology, Ghent University, K.L. Ledeganckststraat 35, B-9000 Ghent, Belgium; (T.D.); (D.V.D.S.)
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9
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Ke M, Ma Z, Wang D, Sun Y, Wen C, Huang D, Chen Z, Yang L, Tan S, Li R, Friml J, Miao Y, Chen X. Salicylic acid regulates PIN2 auxin transporter hyperclustering and root gravitropic growth via Remorin-dependent lipid nanodomain organisation in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2021; 229:963-978. [PMID: 32901934 PMCID: PMC7821329 DOI: 10.1111/nph.16915] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/23/2020] [Indexed: 05/20/2023]
Abstract
To adapt to the diverse array of biotic and abiotic cues, plants have evolved sophisticated mechanisms to sense changes in environmental conditions and modulate their growth. Growth-promoting hormones and defence signalling fine tune plant development antagonistically. During host-pathogen interactions, this defence-growth trade-off is mediated by the counteractive effects of the defence hormone salicylic acid (SA) and the growth hormone auxin. Here we revealed an underlying mechanism of SA regulating auxin signalling by constraining the plasma membrane dynamics of PIN2 auxin efflux transporter in Arabidopsis thaliana roots. The lateral diffusion of PIN2 proteins is constrained by SA signalling, during which PIN2 proteins are condensed into hyperclusters depending on REM1.2-mediated nanodomain compartmentalisation. Furthermore, membrane nanodomain compartmentalisation by SA or Remorin (REM) assembly significantly suppressed clathrin-mediated endocytosis. Consequently, SA-induced heterogeneous surface condensation disrupted asymmetric auxin distribution and the resultant gravitropic response. Our results demonstrated a defence-growth trade-off mechanism by which SA signalling crosstalked with auxin transport by concentrating membrane-resident PIN2 into heterogeneous compartments.
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Affiliation(s)
- Meiyu Ke
- College of Life Science and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyFujian Agriculture and Forestry UniversityFuzhou350002China
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
| | - Zhiming Ma
- School of Biological SciencesNanyang Technological UniversitySingapore637551Singapore
| | - Deyan Wang
- College of Life Science and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyFujian Agriculture and Forestry UniversityFuzhou350002China
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
| | - Yanbiao Sun
- College of Life Science and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyFujian Agriculture and Forestry UniversityFuzhou350002China
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
| | - Chenjin Wen
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
| | - Dingquan Huang
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
| | - Zichen Chen
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
| | - Liang Yang
- School of Biological SciencesNanyang Technological UniversitySingapore637551Singapore
- Singapore Centre for Environmental Life Sciences EngineeringNanyang Technological UniversitySingapore637551Singapore
| | - Shutang Tan
- Institute of Science and Technology Austria (IST Austria)Am Campus 1Klosterneuburg3400Austria
| | - Ruixi Li
- Department of BiologySouthern University of Science and TechnologyShenzhen518055China
| | - Jiří Friml
- Institute of Science and Technology Austria (IST Austria)Am Campus 1Klosterneuburg3400Austria
| | - Yansong Miao
- School of Biological SciencesNanyang Technological UniversitySingapore637551Singapore
| | - Xu Chen
- Haixia Institute of Science and TechnologyHorticultural Plant Biology and Metabolomics CentreFujian Agriculture and Forestry UniversityFuzhou350002China
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10
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NMR spectroscopy analysis reveals differential metabolic responses in arabidopsis roots and leaves treated with a cytokinesis inhibitor. PLoS One 2020; 15:e0241627. [PMID: 33156865 PMCID: PMC7647083 DOI: 10.1371/journal.pone.0241627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/16/2020] [Indexed: 12/26/2022] Open
Abstract
In plant cytokinesis, de novo formation of a cell plate evolving into the new cell wall partitions the cytoplasm of the dividing cell. In our earlier chemical genomics studies, we identified and characterized the small molecule endosidin-7, that specifically inhibits callose deposition at the cell plate, arresting late-stage cytokinesis in arabidopsis. Endosidin-7 has emerged as a very valuable tool for dissecting this essential plant process. To gain insights regarding its mode of action and the effects of cytokinesis inhibition on the overall plant response, we investigated the effect of endosidin-7 through a nuclear magnetic resonance spectroscopy (NMR) metabolomics approach. In this case study, metabolomics profiles of arabidopsis leaf and root tissues were analyzed at different growth stages and endosidin-7 exposure levels. The results show leaf and root-specific metabolic profile changes and the effects of endosidin-7 treatment on these metabolomes. Statistical analyses indicated that the effect of endosidin-7 treatment was more significant than the developmental impact. The endosidin-7 induced metabolic profiles suggest compensations for cytokinesis inhibition in central metabolism pathways. This study further shows that long-term treatment of endosidin-7 profoundly changes, likely via alteration of hormonal regulation, the primary metabolism of arabidopsis seedlings. Hormonal pathway-changes are likely reflecting the plant’s responses, compensating for the arrested cell division, which in turn are leading to global metabolite modulation. The presented NMR spectral data are made available through the Metabolomics Workbench, providing a reference resource for the scientific community.
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11
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Ibragimova N, Mokshina N, Ageeva M, Gurjanov O, Mikshina P. Rearrangement of the Cellulose-Enriched Cell Wall in Flax Phloem Fibers over the Course of the Gravitropic Reaction. Int J Mol Sci 2020; 21:ijms21155322. [PMID: 32727025 PMCID: PMC7432630 DOI: 10.3390/ijms21155322] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 11/23/2022] Open
Abstract
The plant cell wall is a complex structure consisting of a polysaccharide network. The rearrangements of the cell wall during the various physiological reactions of plants, however, are still not fully characterized. Profound changes in cell wall organization are detected by microscopy in the phloem fibers of flax (Linum usitatissimum) during the restoration of the vertical position of the inclined stems. To characterize the underlying biochemical and structural changes in the major cell wall polysaccharides, we compared the fiber cell walls of non-inclined and gravistimulated plants by focusing mainly on differences in non-cellulosic polysaccharides and the fine cellulose structure. Biochemical analysis revealed a slight increase in the content of pectins in the fiber cell walls of gravistimulated plants as well as an increase in accessibility for labeling non-cellulosic polysaccharides. The presence of galactosylated xyloglucan in the gelatinous cell wall layer of flax fibers was demonstrated, and its labeling was more pronounced in the gravistimulated plants. Using solid state NMR, an increase in the crystallinity of the cellulose in gravistimulated plants, along with a decrease in cellulose mobility, was demonstrated. Thus, gravistimulation may affect the rearrangement of the cell wall, which can enable restoration in a vertical position of the plant stem.
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12
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Molecular Evidences for the Interactions of Auxin, Gibberellin, and Cytokinin in Bent Peduncle Phenomenon in Rose ( Rosa sp.). Int J Mol Sci 2020; 21:ijms21041360. [PMID: 32085472 PMCID: PMC7072929 DOI: 10.3390/ijms21041360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/08/2020] [Accepted: 02/14/2020] [Indexed: 12/03/2022] Open
Abstract
In roses (Rosa sp.), peduncle morphology is an important ornamental feature. The common physiological abnormality known as the bent peduncle phenomenon (BPP) seriously decreases the quality of rose flowers and thus the commercial value. Because the molecular mechanisms underlying this condition are poorly understood, we analysed the transcriptional profiles and cellular structures of bent rose peduncles. Numerous differentially expressed genes involved in the auxin, cytokinin, and gibberellin signaling pathways were shown to be associated with bent peduncle. Paraffin sections showed that the cell number on the upper sides of bent peduncles was increased, while the cells on the lower sides were larger than those in normal peduncles. We also investigated the large, deformed sepals that usually accompany BPP and found increased expression level of some auxin-responsive genes and decreased expression level of genes that are involved in cytokinin and gibberellin synthesis in these sepals. Furthermore, removal of the deformed sepals partially relieved BPP. In summary, our findings suggest that auxin, cytokinin, and gibberellin all influence the development of BPP by regulating cell division and expansion. To effectively reduce BPP in roses, more efforts need to be devoted to the molecular regulation of gibberellins and cytokinins in addition to that of auxin.
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13
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Bahmani R, Kim D, Modareszadeh M, Thompson AJ, Park JH, Yoo HH, Hwang S. The mechanism of root growth inhibition by the endocrine disruptor bisphenol A (BPA). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 257:113516. [PMID: 31733969 DOI: 10.1016/j.envpol.2019.113516] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/18/2019] [Accepted: 10/28/2019] [Indexed: 05/12/2023]
Abstract
Bisphenol A (BPA) is a harmful environmental contaminant acting as an endocrine disruptor in animals, but it also affects growth and development in plants. Here, we have elucidated the functional mechanism of root growth inhibition by BPA in Arabidopsis thaliana using mutants, reporter lines and a pharmacological approach. In response to 10 ppm BPA, fresh weight and main root length were reduced, while auxin levels increased. BPA inhibited root growth by reducing root cell length in the elongation zone by suppressing expansin expression and by decreasing the length of the meristem zone by repressing cell division. The inhibition of cell elongation and cell division was attributed to the enhanced accumulation/redistribution of auxin in the elongation zone and meristem zone in response to BPA. Correspondingly, the expressions of most auxin biosynthesis and transporter genes were enhanced in roots by BPA. Taken together, it is assumed that the endocrine disruptor BPA inhibits primary root growth by inhibiting cell elongation and division through auxin accumulation/redistribution in Arabidopsis. This study will contribute to understanding how BPA affects growth and development in plants.
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Affiliation(s)
- Ramin Bahmani
- Department of Molecular Biology, Sejong University, Seoul, 143-747, South Korea; Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, South Korea; The Plant Engineering Research Institute, Sejong University, Seoul, 143-747, South Korea
| | - DongGwan Kim
- Department of Molecular Biology, Sejong University, Seoul, 143-747, South Korea; Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, South Korea; The Plant Engineering Research Institute, Sejong University, Seoul, 143-747, South Korea
| | - Mahsa Modareszadeh
- Department of Molecular Biology, Sejong University, Seoul, 143-747, South Korea; Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, South Korea; The Plant Engineering Research Institute, Sejong University, Seoul, 143-747, South Korea
| | - Andrew J Thompson
- Cranfield Soil and Agrifood Institute, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK
| | - Jeong Hoon Park
- College of Pharmacy, Hanyang University, Ansan, Gyeonggi-do 15588, South Korea
| | - Hye Hyun Yoo
- College of Pharmacy, Hanyang University, Ansan, Gyeonggi-do 15588, South Korea
| | - Seongbin Hwang
- Department of Molecular Biology, Sejong University, Seoul, 143-747, South Korea; Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, South Korea; The Plant Engineering Research Institute, Sejong University, Seoul, 143-747, South Korea.
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Asymmetric distribution of cytokinins determines root hydrotropism in Arabidopsis thaliana. Cell Res 2019; 29:984-993. [PMID: 31601978 PMCID: PMC6951336 DOI: 10.1038/s41422-019-0239-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/05/2019] [Indexed: 11/17/2022] Open
Abstract
The phenomenon of plant root tips sensing moisture gradient in soil and growing towards higher water potential is designated as root hydrotropism, which is critical for plants to survive when water is a limited factor. Molecular mechanisms regulating such a fundamental process, however, are largely unknown. Here we report our identification that cytokinins are key signaling molecules directing root growth orientation in a hydrostimulation (moisture gradient) condition. Lower water potential side of the root tip shows more cytokinin response relative to the higher water potential side. Consequently, two cytokinin downstream type-A response regulators, ARR16 and ARR17, were found to be up-regulated at the lower water potential side, causing increased cell division in the meristem zone, which allows the root to bend towards higher water potential side. Genetic analyses indicated that various cytokinin biosynthesis and signaling mutants, including the arr16 arr17 double mutant, are significantly less responsive to hydrostimulation. Consistently, treatments with chemical inhibitors interfering with either cytokinin biosynthesis or cell division completely abolished root hydrotropic response. Asymmetrically induced expression of ARR16 or ARR17 effectively led to root bending in both wild-type and miz1, a previously known hydrotropism-defective mutant. These data demonstrate that asymmetric cytokinin distribution is a primary determinant governing root hydrotropism.
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Bessho-Uehara K, Nugroho JE, Kondo H, Angeles-Shim RB, Ashikari M. Sucrose affects the developmental transition of rhizomes in Oryza longistaminata. JOURNAL OF PLANT RESEARCH 2018; 131:693-707. [PMID: 29740707 PMCID: PMC6488557 DOI: 10.1007/s10265-018-1033-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/08/2018] [Indexed: 05/29/2023]
Abstract
Oryza longistaminata, the African wild rice, can propagate vegetatively through rhizomes. Rhizomes elongate horizontally underground as sink organs, however, they undergo a developmental transition that shifts their growth to the surface of the ground to become aerial stems. This particular stage is essential for the establishment of new ramets. While several determinants such as abiotic stimuli and plant hormones have been reported as key factors effecting developmental transition in aerial stem, the cause of this phenomenon in rhizome remains elusive. This study shows that depletion of nutrients, particularly sucrose, is the key stimulus that induces the developmental transition in rhizomes, as indicated by the gradient of sugars from the base to the tip of the rhizome. Sugar treatments revealed that sucrose specifically represses the developmental transition from rhizome to aerial stem by inhibiting the expression of sugar metabolism and hormone synthesis genes at the bending point. Sucrose depletion affected several factors contributing to the developmental transition of rhizome including signal transduction, transcriptional regulation and plant hormone balance.
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Affiliation(s)
- Kanako Bessho-Uehara
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan
| | - Jovano Erris Nugroho
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan
| | - Hirono Kondo
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan
| | - Rosalyn B Angeles-Shim
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX, 79409, USA
| | - Motoyuki Ashikari
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan.
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Wang L, Guo M, Li Y, Ruan W, Mo X, Wu Z, Sturrock CJ, Yu H, Lu C, Peng J, Mao C. LARGE ROOT ANGLE1, encoding OsPIN2, is involved in root system architecture in rice. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:385-397. [PMID: 29294052 PMCID: PMC5853395 DOI: 10.1093/jxb/erx427] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 11/13/2017] [Indexed: 05/17/2023]
Abstract
Root system architecture is very important for plant growth and crop yield. It is essential for nutrient and water uptake, anchoring, and mechanical support. Root growth angle (RGA) is a vital constituent of root system architecture and is used as a parameter for variety evaluation in plant breeding. However, little is known about the underlying molecular mechanisms that determine root growth angle in rice (Oryza sativa). In this study, a rice mutant large root angle1 (lra1) was isolated and shown to exhibit a large RGA and reduced sensitivity to gravity. Genome resequencing and complementation assays identified OsPIN2 as the gene responsible for the mutant phenotypes. OsPIN2 was mainly expressed in roots and the base of shoots, and showed polar localization in the plasma membrane of root epidermal and cortex cells. OsPIN2 was shown to play an important role in mediating root gravitropic responses in rice and was essential for plants to produce normal RGAs. Taken together, our findings suggest that OsPIN2 plays an important role in root gravitropic responses and determining the root system architecture in rice by affecting polar auxin transport in the root tip.
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Affiliation(s)
- Lingling Wang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Mengxue Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yong Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Wenyuan Ruan
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Xiaorong Mo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Zhongchang Wu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Craig J Sturrock
- The Hounsfield Facility, School of Biosciences, University of Nottingham, Nottingham, UK
| | - Hao Yu
- Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of Singapore, Singapore
| | - Chungui Lu
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Nottingham, UK
| | - Jinrong Peng
- College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Chuanzao Mao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
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Chen L, Guo X, Cui Y, Zheng X, Yang H. Comparative Transcriptome Analysis Reveals Hormone Signaling Genes Involved in the Launch of Culm-Shape Differentiation in Dendrocalamus sinicus. Genes (Basel) 2017; 9:E4. [PMID: 29271945 PMCID: PMC5793157 DOI: 10.3390/genes9010004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 12/09/2017] [Accepted: 12/20/2017] [Indexed: 12/23/2022] Open
Abstract
Dendrocalamus sinicus is a sympodial bamboo species endemic to Yunnan Province, China, and is the strongest bamboo species in the world. However, there is substantial variation in the basal culm shape, i.e., straight culm (SC) and bent culm (BC), among different D. sinicus as a result of genetic and growth factors. This study performed a comparative transcriptomic analysis of bamboo shoots of two variants at the early, mid-, and late shoot-development stages to examine the molecular basis of this variation. In total, 98,479 unigenes were annotated, of which 13,495 were differentially expressed in pairwise comparisons of the six libraries. More differentially expressed genes (DEGs) were involved in SC than in BC culm development. The DEGs between BC and SC were assigned to 108 metabolic pathways. The 1064 DEGs in early development might mainly control the launch of culm-shape differentiation. Sixty genes encoding components of hormone signaling pathways were differentially expressed between BC5 and SC5, indicating complex hormonal regulation of culm differentiation. The AUX/IAA, ARF, PP2C, SnRK2, and ABF genes involved in auxin and abscisic acid signaling played key roles. These results help us to understand the molecular mechanism of culm variation and other aspects of culm development in D. sinicus.
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Affiliation(s)
- Lingna Chen
- Research Institute of Resources Insects, Chinese Academy of Forestry, Bailongsi, Panlong, Kunming 650233, China.
| | - Xiaojuan Guo
- Research Institute of Resources Insects, Chinese Academy of Forestry, Bailongsi, Panlong, Kunming 650233, China.
| | - Yongzhong Cui
- Research Institute of Resources Insects, Chinese Academy of Forestry, Bailongsi, Panlong, Kunming 650233, China.
| | - Xianggan Zheng
- Research Institute of Resources Insects, Chinese Academy of Forestry, Bailongsi, Panlong, Kunming 650233, China.
| | - Hanqi Yang
- Research Institute of Resources Insects, Chinese Academy of Forestry, Bailongsi, Panlong, Kunming 650233, China.
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18
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Singh M, Gupta A, Laxmi A. Striking the Right Chord: Signaling Enigma during Root Gravitropism. FRONTIERS IN PLANT SCIENCE 2017; 8:1304. [PMID: 28798760 PMCID: PMC5529344 DOI: 10.3389/fpls.2017.01304] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 07/11/2017] [Indexed: 05/29/2023]
Abstract
Plants being sessile can often be judged as passive acceptors of their environment. However, plants are actually even more active in responding to the factors from their surroundings. Plants do not have eyes, ears or vestibular system like animals, still they "know" which way is up and which way is down? This is facilitated by receptor molecules within plant which perceive changes in internal and external conditions such as light, touch, obstacles; and initiate signaling pathways that enable the plant to react. Plant responses that involve a definite and specific movement are called "tropic" responses. Perhaps the best known and studied tropisms are phototropism, i.e., response to light, and geotropism, i.e., response to gravity. A robust root system is vital for plant growth as it can provide physical anchorage to soil as well as absorb water, nutrients and essential minerals from soil efficiently. Gravitropic responses of both primary as well as lateral root thus become critical for plant growth and development. The molecular mechanisms of root gravitropism has been delved intensively, however, the mechanism behind how the potential energy of gravity stimulus converts into a biochemical signal in vascular plants is still unknown, due to which gravity sensing in plants still remains one of the most fascinating questions in molecular biology. Communications within plants occur through phytohormones and other chemical substances produced in plants which have a developmental or physiological effect on growth. Here, we review current knowledge of various intrinsic signaling mechanisms that modulate root gravitropism in order to point out the questions and emerging developments in plant directional growth responses. We are also discussing the roles of sugar signals and their interaction with phytohormone machinery, specifically in context of root directional responses.
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Affiliation(s)
- Manjul Singh
- National Institute of Plant Genome ResearchNew Delhi, India
- Interdisciplinary Centre for Plant Genomics, University of Delhi South CampusNew Delhi, India
| | - Aditi Gupta
- National Institute of Plant Genome ResearchNew Delhi, India
- Interdisciplinary Centre for Plant Genomics, University of Delhi South CampusNew Delhi, India
| | - Ashverya Laxmi
- National Institute of Plant Genome ResearchNew Delhi, India
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19
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Genome-Wide Association Study Dissecting the Genetic Architecture Underlying the Branch Angle Trait in Rapeseed (Brassica napus L.). Sci Rep 2016; 6:33673. [PMID: 27646167 PMCID: PMC5028734 DOI: 10.1038/srep33673] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 08/31/2016] [Indexed: 12/04/2022] Open
Abstract
The rapeseed branch angle is an important morphological trait because an adequate branch angle enables more efficient light capture under high planting densities. Here, we report that the average angle of the five top branches provides a reliable representation of the average angle of all branches. Statistical analyses revealed a significantly positive correlation between the branch angle and multiple plant-type and yield-related traits. The 60 K Brassica Infinium® single nucleotide polymorphism (SNP) array was utilized to genotype an association panel with 520 diverse accessions. A genome-wide association study was performed to determine the genetic architecture of branch angle, and 56 loci were identified as being significantly associated with the branch angle trait via three models, including a robust, novel, nonparametric Anderson-Darling (A-D) test. Moreover, these loci explained 51.1% of the phenotypic variation when a simple additive model was applied. Within the linkage disequilibrium (LD) decay ranges of 53 loci, we observed plausible candidates orthologous to documented Arabidopsis genes, such as LAZY1, SGR2, SGR4, SGR8, SGR9, PIN3, PIN7, CRK5, TIR1, and APD7. These results provide insight into the genetic basis of the branch angle trait in rapeseed and might facilitate marker-based breeding for improvements in plant architecture.
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20
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Philosoph-Hadas S, Friedman H, Meir S. Flowering shoots of ornamental crops as a model to study cellular and molecular aspects of plant gravitropism. Methods Mol Biol 2016; 1309:171-98. [PMID: 25981776 DOI: 10.1007/978-1-4939-2697-8_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Flowering shoots offer a very convenient and excellent model system for in-depth study of shoot gravitropism in regular stems rather than in special aboveground organs, showing how plants cope with the force of gravity on Earth and change in orientation. Regarding the emerging notion that roots and shoots execute their gravitropic bending by different mechanisms, the use of flowering shoots offers additional confirmation for the suggested shoot-sensing mechanisms initially found in Arabidopsis. As a part of confirming this mechanism, studying this unique model system also enabled elucidation of the sequence of events operating in gravity signalling in shoots. Hence, using the system of flowering shoots provided an additional dimension to our understanding of shoot gravitropism and its hormonal regulation, which has been less advanced than root gravitropism. This is particularly important since the term "shoots" includes various aboveground organs. Hence, unlike other aboveground organs such as pulvini, the asymmetric growth in response to change in shoot orientation is accompanied in cut ornamental spikes by a continuous growth process. This chapter provides an overview of the basic methods, specifically developed or adapted from other graviresponding systems, for determining the main components which play a key role in gravistimulation signalling in flowering shoots.
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Affiliation(s)
- Sonia Philosoph-Hadas
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), The Volcani Center, 6, Bet-Dagan, 5025001, Israel,
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Niu Y, Jin G, Li X, Tang C, Zhang Y, Liang Y, Yu J. Phosphorus and magnesium interactively modulate the elongation and directional growth of primary roots in Arabidopsis thaliana (L.) Heynh. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:3841-54. [PMID: 25922494 PMCID: PMC4473981 DOI: 10.1093/jxb/erv181] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A balanced supply of essential nutrients is an important factor influencing root architecture in many plants, yet data related to the interactive effects of two nutrients on root growth are limited. Here, we investigated the interactive effect between phosphorus (P) and magnesium (Mg) on root growth of Arabidopsis grown in pH-buffered agar medium at different P and Mg levels. The results showed that elongation and deviation of primary roots were directly correlated with the amount of P added to the medium but could be modified by the Mg level, which was related to the root meristem activity and stem-cell division. High P enhanced while low P decreased the tip-focused fluorescence signal of auxin biosynthesis, transport, and redistribution during elongation of primary roots; these effects were greater under low Mg than under high Mg. The altered root growth in response to P and Mg supply was correlated with AUX1, PIN2, and PIN3 mRNA abundance and expression and the accumulation of the protein. Application of either auxin influx inhibitor or efflux inhibitor inhibited the elongation and increased the deviation angle of primary roots, and decreased auxin level in root tips. Furthermore, the auxin-transport mutants aux1-22 and eir1-1 displayed reduced root growth and increased the deviation angle. Our data suggest a profound effect of the combined supply of P and Mg on the development of root morphology in Arabidopsis through auxin signals that modulate the elongation and directional growth of primary root and the expression of root differentiation and development genes.
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Affiliation(s)
- Yaofang Niu
- Department of Horticulture, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou 310058, PR China College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, PR China
| | - Gulei Jin
- College of Agricultural and Biotechnology, Zhejiang University, Hangzhou 310058, PR China
| | - Xin Li
- Tea Research Institute, Chinese Academy of Agricultural Science, Hangzhou, 310008, PR China
| | - Caixian Tang
- Centre for AgriBioscience, La Trobe University, Melbourne Campus, Victoria 3086, Australia
| | - Yongsong Zhang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, PR China
| | - Yongchao Liang
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, PR China
| | - Jingquan Yu
- Department of Horticulture, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou 310058, PR China
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Hung CY, Umstead ML, Chen J, Holliday BM, Kittur FS, Henny RJ, Burkey KO, Xie J. Differential expression of a novel gene EaF82a in green and yellow sectors of variegated Epipremnum aureum leaves is related to uneven distribution of auxin. PHYSIOLOGIA PLANTARUM 2014; 152:749-62. [PMID: 24796240 DOI: 10.1111/ppl.12219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 02/26/2014] [Accepted: 03/24/2014] [Indexed: 06/03/2023]
Abstract
EaF82, a gene identified in previous studies of the variegated plant Epipremnum aureum, exhibited a unique expression pattern with greater transcript abundance in yellow sectors than green sectors of variegated leaves, but lower abundance in regenerated pale yellow plants than in green plants derived from leaf tissue culture. Studies of its full-length cDNA and promoter region revealed two members with only the EaF82a expressed. Immunoblotting confirmed that EaF82a encodes a 12 kDa protein and its accumulation consistent with its gene expression patterns in different color tissues. Transient expression of EaF82a-sGFP fusion proteins in protoplasts showed that EaF82a seems to be present in the cytosol as unidentified spots. Sequence motif search reveals a potential auxin responsive element in promoter region. Using transgenic Arabidopsis seedlings carrying EaF82a promoter driving the bacterial uidA (GUS) gene, an increased GUS activity was observed when IAA (indole-3-acetic acid) concentration was elevated. In E. aureum, EaF82a is more abundant at the site where axillary buds emerge and at the lower side of bending nodes where more IAA accumulates relative to the upper side. The measurement of endogenous IAA levels in different color tissues revealed the same pattern of IAA distribution as that of EaF82a expression, further supporting that EaF82a is an IAA responsive gene. EaF82a expression in etiolated transgenic Arabidopsis seedlings responded to IAA under the influence of light suggesting a microenvironment of uneven light condition affects the EaF82a transcript levels and protein accumulation in variegated leaves.
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Affiliation(s)
- Chiu-Yueh Hung
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute & Technology Enterprise, North Carolina Central University, Durham, 27707, USA
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23
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Wan L, Wu Y, Huang J, Dai X, Lei Y, Yan L, Jiang H, Zhang J, Varshney RK, Liao B. Identification of ERF genes in peanuts and functional analysis of AhERF008 and AhERF019 in abiotic stress response. Funct Integr Genomics 2014; 14:467-77. [PMID: 24902799 DOI: 10.1007/s10142-014-0381-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Revised: 05/13/2014] [Accepted: 05/26/2014] [Indexed: 12/24/2022]
Abstract
Ethylene-responsive factor (ERF) play an important role in regulating gene expression in plant development and response to stresses. In peanuts (Arachis hypogaea L.), which produce flowers aerially and pods underground, only a few ERF genes have been identified so far. This study identifies 63 ERF unigenes from 247,313 peanut EST sequences available in the NCBI database. The phylogeny, gene structures, and putative conserved motifs in the peanut ERF proteins were analysed. Comparative analysis revealed the absence of two subgroups (A1 and A3) of the ERF family in peanuts; only 10 subgroups were identified in peanuts compared to 12 subgroups in Arabidopsis and soybeans. AP2/ERF domains were found to be conserved among peanuts, Arabidopsis, and soybeans. Outside the AP2/ERF domain, many soybean-specific conserved motifs were also detected in peanuts. The expression analysis of ERF family genes representing each clade revealed differential expression patterns in response to biotic and abiotic stresses. Overexpression of AhERF008 influenced the root gravity of Arabidopsis, whereas overexpression of AhERF019 enhanced tolerance to drought, heat, and salt stresses in Arabidopsis. The information generated in this study will be helpful to further investigate the function of ERFs in plant development and stress response.
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Affiliation(s)
- Liyun Wan
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Wuhan, China,
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24
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Singh M, Gupta A, Laxmi A. Glucose control of root growth direction in Arabidopsis thaliana. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2981-93. [PMID: 24719453 PMCID: PMC4071822 DOI: 10.1093/jxb/eru146] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Directional growth of roots is a complex process that is modulated by various environmental signals. This work shows that presence of glucose (Glc) in the medium also extensively modulated seedling root growth direction. Glc modulation of root growth direction was dramatically enhanced by simultaneous brassinosteroid (BR) application. Glc enhanced BR receptor BRASSINOSTEROID INSENSITIVE1 (BRI1) endocytosis from plasma membrane to early endosomes. Glc-induced root deviation was highly enhanced in a PP2A-defective mutant, roots curl in naphthyl phthalamic acid 1-1 (rcn1-1) suggesting that there is a role of phosphatase in Glc-induced root-growth deviation. RCN1, therefore, acted as a link between Glc and the BR-signalling pathway. Polar auxin transport worked further downstream to BR in controlling Glc-induced root deviation response. Glc also affected other root directional responses such as root waving and coiling leading to altered root architecture. High light intensity mimicked the Glc-induced changes in root architecture that were highly reduced in Glc-signalling mutants. Thus, under natural environmental conditions, changing light flux in the environment may lead to enhanced Glc production/response and is a way to manipulate root architecture for optimized development via integrating several extrinsic and intrinsic signalling cues.
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Affiliation(s)
- Manjul Singh
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Aditi Gupta
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Ashverya Laxmi
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India
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Singh M, Gupta A, Laxmi A. Glucose and phytohormone interplay in controlling root directional growth in Arabidopsis. PLANT SIGNALING & BEHAVIOR 2014; 9:e29219. [PMID: 25763496 PMCID: PMC4203494 DOI: 10.4161/psb.29219] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Sensing and responding toward gravity vector is a complicated and multistep process. Gravity is a constant factor feeding plants with reliable information for the spatial orientation of their organs. Auxin, cytokinin, ethylene and BRs have been the most explored hormones in relation to gravitropism. We have previously shown that glucose (Glc) could promote brassinosteroid (BR) signaling thereby inducing changes in root directional growth. Auxin signaling and polar transport components are also involved in Glc induced changes in root directional growth. Here, we provide evidence for involvement of cytokinin and ethylene signaling components in regulation of root directional growth downstream to Glc and BR. Altogether, Glc mediated change in root direction is an adaptive feature which is a result of a collaborative effort integrating phytohormonal signaling cues.
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Li X, Yang X, Wu HX. Transcriptome profiling of radiata pine branches reveals new insights into reaction wood formation with implications in plant gravitropism. BMC Genomics 2013; 14:768. [PMID: 24209714 PMCID: PMC4046691 DOI: 10.1186/1471-2164-14-768] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 10/29/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Formation of compression (CW) and opposite wood (OW) in branches and bent trunks is an adaptive feature of conifer trees in response to various displacement forces, such as gravity, wind, snow and artificial bending. Several previous studies have characterized tracheids, wood and gene transcription in artificially or naturally bent conifer trunks. These studies have provided molecular basis of reaction wood formation in response to bending forces and gravity stimulus. However, little is known about reaction wood formation and gene transcription in conifer branches under gravity stress. In this study SilviScan® technology was used to characterize tracheid and wood traits in radiate pine (Pinus radiata D. Don) branches and genes differentially transcribed in CW and OW were investigated using cDNA microarrays. RESULTS CW drastically differed from OW in tracheids and wood traits with increased growth, thicker tracheid walls, larger microfibril angle (MFA), higher density and lower stiffness. However, CW and OW tracheids had similar diameters in either radial or tangential direction. Thus, gravity stress largely influenced wood growth, secondary wall deposition, cellulose microfibril orientation and wood properties, but had little impact on primary wall expansion. Microarray gene transcription revealed about 29% of the xylem transcriptomes were significantly altered in CW and OW sampled in both spring and autumn, providing molecular evidence for the drastic variation in tracheid and wood traits. Genes involved in cell division, cellulose biosynthesis, lignin deposition, and microtubules were mostly up-regulated in CW, conferring its greater growth, thicker tracheid walls, higher density, larger MFA and lower stiffness. However, genes with roles in cell expansion and primary wall formation were differentially transcribed in CW and OW, respectively, implicating their similar diameters of tracheid walls and different tracheid lengths. Interestingly, many genes related to hormone and calcium signalling as well as various environmental stresses were exclusively up-regulated in CW, providing important clues for earlier molecular signatures of reaction wood formation under gravity stimulus. CONCLUSIONS The first comprehensive investigation of tracheid characteristics, wood properties and gene transcription in branches of a conifer species revealed more accurate and new insights into reaction wood formation in response to gravity stress. The identified differentially transcribed genes with diverse functions conferred or implicated drastic CW and OW variation observed in radiata pine branches. These genes are excellent candidates for further researches on the molecular mechanisms of reaction wood formation with a view to plant gravitropism.
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Affiliation(s)
- Xinguo Li
- />CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601 Australia
| | - Xiaohui Yang
- />CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601 Australia
- />Department of Biotechnology, Beijing Forestry University, Beijing, 100083 China
| | - Harry X Wu
- />CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601 Australia
- />Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden
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Song S, Qi T, Huang H, Xie D. Regulation of stamen development by coordinated actions of jasmonate, auxin, and gibberellin in Arabidopsis. MOLECULAR PLANT 2013; 6:1065-73. [PMID: 23543439 DOI: 10.1093/mp/sst054] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Proper stamen development is essential for plants to achieve their life cycles. Defects in stamen development will cause male sterility. A vast array of research efforts have been made to understand stamen developmental processes and regulatory mechanisms over the past decades. It is so far reported that phytohormones, including jasmonate, auxin, gibberellin, brassinosteroid, and cytokinin, play essential roles in regulation of stamen development. This review will briefly summarize the molecular basis for coordinated regulation of stamen development by jasmonate, auxin, and gibberellin in Arabidopsis.
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Affiliation(s)
- Susheng Song
- Tsinghua-Peking Center for Life Sciences, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
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Gupta A, Singh M, Jones AM, Laxmi A. Hypocotyl directional growth in Arabidopsis: a complex trait. PLANT PHYSIOLOGY 2012; 159:1463-76. [PMID: 22689891 PMCID: PMC3425191 DOI: 10.1104/pp.112.195776] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The growth direction of the Arabidopsis (Arabidopsis thaliana) etiolated-seedling hypocotyl is a complex trait that is controlled by extrinsic signals such as gravity and touch as well as intrinsic signals such as hormones (brassinosteroid [BR], auxin, cytokinin, ethylene) and nutrient status (glucose [Glc], sucrose). We used a genetic approach to identify the signaling elements and their relationship underlying hypocotyl growth direction. BR randomizes etiolated-seedling growth by inhibiting negative gravitropism of the hypocotyls via modulating auxin homeostasis for which we designate as reset, not to be confused with the gravity set point angle. Cytokinin signaling antagonizes this BR reset of gravity sensing and/or tropism by affecting ethylene biosynthesis/signaling. Glc also antagonizes BR reset but acts independently of cytokinin and ethylene signaling pathways via inhibiting BR-regulated gene expression quantitatively and spatially, by altering protein degradation, and by antagonizing BR-induced changes in microtubule organization and cell patterning associated with hypocotyl agravitropism. This BR reset is reduced in the presence of the microtubule organization inhibitor oryzalin, suggesting a central role for cytoskeleton reorganization. A unifying and hierarchical model of Glc and hormone signaling interplay is proposed. The biological significance of BR-mediated changes in hypocotyl graviresponse lies in the fact that BR signaling sensitizes the dark-grown seedling hypocotyl to the presence of obstacles, overriding gravitropism, to enable efficient circumnavigation through soil.
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Sakai T, Mochizuki S, Haga K, Uehara Y, Suzuki A, Harada A, Wada T, Ishiguro S, Okada K. The wavy growth 3 E3 ligase family controls the gravitropic response in Arabidopsis roots. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 70:303-14. [PMID: 22122664 DOI: 10.1111/j.1365-313x.2011.04870.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Regulation of the root growth pattern is an important control mechanism during plant growth and propagation. To better understand alterations in root growth direction in response to environmental stimuli, we have characterized an Arabidopsis thaliana mutant, wavy growth 3 (wav3), whose roots show a short-pitch pattern of wavy growth on inclined agar medium. The wav3 mutant shows a greater curvature of root bending in response to gravity, but a smaller curvature in response to light, suggesting that it is a root gravitropism-enhancing mutation. This wav3 phenotype also suggests that enhancement of the gravitropic response in roots strengthens root tip impedance after contact with the agar surface and/or causes an increase in subsequent root bending in response to obstacle-touching stimulus in these mutants. WAV3 encodes a protein with a RING finger domain, and is mainly expressed in root tips. RING-containing proteins often function as an E3 ubiquitin ligase, and the WAV3 protein shows such activity in vitro. There are three genes homologous to WAV3 in the Arabidopsis genome [EMBRYO SAC DEVELOPMENT ARREST 40 (EDA40), WAVH1 and WAVH2 ], and wav3 wavh1 wavh2 triple mutants show marked root gravitropism abnormalities. This genetic study indicates that WAV3 functions positively rather than negatively in root gravitropism, and that enhancement of the gravitropic response in wav3 roots is dependent upon the function of WAVH2 in the absence of WAV3. Hence, our results demonstrate that the WAV3 family of proteins are E3 ligases that are required for root gravitropism in Arabidopsis.
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Affiliation(s)
- Tatsuya Sakai
- Graduate School of Science and Technology, Niigata University, Nishi-ku, Niigata 950-2181, Japan.
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Lee Y, Park CH, Ram Kim A, Chang SC, Kim SH, Lee WS, Kim SK. The effect of ascorbic acid and dehydroascorbic acid on the root gravitropic response in Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2011; 49:909-16. [PMID: 21696975 DOI: 10.1016/j.plaphy.2011.05.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 05/31/2011] [Indexed: 05/09/2023]
Abstract
The effects of ascorbic acid (AA) and dehydroascorbic acid (DHA), one of products of the disproportionation of monodehydroascorbate (MDHA) by AA oxidase (AAO, EC 1.10.3.3), on the gravitropic curvature of Arabidopsis roots were characterized by biochemical and genetic approaches. Exogenously applied AA and DHA both stimulated root gravitropic responses in a concentration-dependent fashion. AA also changed the Indole-3-acetic acid (IAA) distribution in the roots after gravistimulation. In an effort to determine the relationship between AA and DHA in the gravitropic response, changes in the amount of reduced AA were evaluated in Arabidopsis under a variety of conditions. The expression level of an AAO gene (AAO1) was increased upon gravistimulation. Brassinolide (BL), indole-3-acetic acid (IAA), and AA also increased the transcript levels of this gene. Root elongation and the gravitropic response were both suppressed in the AA biosynthesis mutant, vtc1, which has a greatly reduced level of total AA. Furthermore, the line of AAO double mutants (aao1-1 X aao3-1, 41-21) showed a reduced gravitropic response and reduced root elongation. Taken together, the results of this study imply that both AA and DHA help to determine the redox environment for the root gravitropic response, but DHA, rather than AA, is a major player in the regulation of the gravitropic response mediated by AA in the roots of Arabidopsis thaliana.
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Affiliation(s)
- Yew Lee
- Department of Life Science, Chung-Ang University, Seoul 156-756, Republic of Korea
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