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Tripathi A, Chauhan N, Mukhopadhyay P. Recent advances in understanding the regulation of plant secondary metabolite biosynthesis by ethylene-mediated pathways. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2024; 30:543-557. [PMID: 38737326 PMCID: PMC11087406 DOI: 10.1007/s12298-024-01441-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 03/12/2024] [Accepted: 03/19/2024] [Indexed: 05/14/2024]
Abstract
Plants produce a large repertoire of secondary metabolites. The pathways that lead to the biosynthesis of these metabolites are majorly conserved in the plant kingdom. However, a significant portion of these metabolites are specific to certain groups or species due to variations in the downstream pathways and evolution of the enzymes. These metabolites show spatiotemporal variation in their accumulation and are of great importance to plants due to their role in development, stress response and survival. A large number of these metabolites are in huge industrial demand due to their potential use as therapeutics, aromatics and more. Ethylene, as a plant hormone is long known, and its biosynthetic process, signaling mechanism and effects on development and response pathways have been characterized in many plants. Through exogenous treatments, ethylene and its inhibitors have been used to manipulate the production of various secondary metabolites. However, the research done on a limited number of plants in the last few years has only started to uncover the mechanisms through which ethylene regulates the accumulation of these metabolites. Often in association with other hormones, ethylene participates in fine-tuning the biosynthesis of the secondary metabolites, and brings specificity in the regulation depending on the plant, organ, tissue type and the prevailing conditions. This review summarizes the related studies, interprets the outcomes, and identifies the gaps that will help to breed better varieties of the related crops and produce high-value secondary metabolites for human benefits.
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Affiliation(s)
- Alka Tripathi
- Plant Biotechnology division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh 226015 India
| | - Nisha Chauhan
- Plant Biotechnology division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh 226015 India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad, Uttar Pradesh 201002 India
| | - Pradipto Mukhopadhyay
- Plant Biotechnology division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh 226015 India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Ghaziabad, Uttar Pradesh 201002 India
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Uemura Y, Kimura S, Ohta T, Suzuki T, Mase K, Kato H, Sakaoka S, Uefune M, Komine Y, Hotta K, Shimizu M, Morikami A, Tsukagoshi H. A very long chain fatty acid responsive transcription factor, MYB93, regulates lateral root development in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1408-1427. [PMID: 37247130 DOI: 10.1111/tpj.16330] [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: 07/22/2022] [Revised: 05/12/2023] [Accepted: 05/23/2023] [Indexed: 05/30/2023]
Abstract
Lateral roots (LRs) are critical to root system architecture development in plants. Although the molecular mechanisms by which auxin regulates LR development have been extensively studied, several additional regulatory systems are hypothesized to be involved. Recently, the regulatory role of very long chain fatty acids (VLCFAs) has been shown in LR development. Our analysis showed that LTPG1 and LTPG2, transporters of VLCFAs, are specifically expressed in the developing LR primordium (LRP), while the number of LRs is reduced in the ltpg1/ltpg2 double mutant. Moreover, late LRP development was hindered when the VLCFA levels were reduced by the VLCFA synthesis enzyme mutant, kcs1-5. However, the details of the regulatory mechanisms of LR development controlled by VLCFAs remain unknown. In this study, we propose a novel method to analyze the LRP development stages with high temporal resolution using a deep neural network and identify a VLCFA-responsive transcription factor, MYB93, via transcriptome analysis of kcs1-5. MYB93 showed a carbon chain length-specific expression response following treatment of VLCFAs. Furthermore, myb93 transcriptome analysis suggested that MYB93 regulated the expression of cell wall organization genes. In addition, we also found that LTPG1 and LTPG2 are involved in LR development through the formation of root cap cuticle, which is different from transcriptional regulation by VLCFAs. Our results suggest that VLCFA is a regulator of LRP development through transcription factor-mediated regulation of gene expression and the transportation of VLCFAs is also involved in LR development through root cap cuticle formation.
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Affiliation(s)
- Yuta Uemura
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Saori Kimura
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Tomomichi Ohta
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Takamasa Suzuki
- Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi, 478-8501, Japan
| | - Kosuke Mase
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Hiroyuki Kato
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Satomi Sakaoka
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Masayoshi Uefune
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Yuki Komine
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Kazuhiro Hotta
- Department of Electrical and Electronic Engineering, Faculty of Science and Technology, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Motoyuki Shimizu
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Atsushi Morikami
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Hironaka Tsukagoshi
- Faculty of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, Aichi, 468-8502, Japan
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Geng X, Wang X, Wang J, Yang X, Zhang L, Song X. TaEXPB5 functions as a gene related to pollen development in thermo-sensitive male-sterility wheat with Aegilops kotschyi cytoplasm. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 323:111377. [PMID: 35820549 DOI: 10.1016/j.plantsci.2022.111377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/04/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
The thermo-sensitive cytoplasmic male-sterility line with Aegilops kotschyi cytoplasm (K-TCMS) is completely male sterile under low temperature (< 18 ℃) during Zadoks growth stages 45-52, whereas its fertility can be restored under hot temperature (≥ 20 ℃). The K-TCMS line may facilitate hybrid breeding and hybrid wheat production. Therefore, to elucidate the molecular mechanisms of its male sterility/fertility conversion, we conducted the association analysis of proteins and transcript expression to screen fertility related genes using RNA-seq, iTRAQ, and PRM-based assay. A gene encoding expansin protein in wheat, TaEXPB5, was isolated in K-TCMS line KTM3315A, which upregulated expression in the fertility anthers. Subcellular localization analysis suggested that TaEXPB5 protein localized to nucleus and cell wall. The silencing of TaEXPB5 displayed pollen abortion and the declination of fertility. Further, cytological investigation indicated that the silencing of TaEXPB5 induced the early degradation of tapetum and abnormal development of pollen wall. These results implied that TaEXPB5 may be essential for anther or pollen development and male fertility of KTM3315A. These findings provide a novel insight into molecular mechanism of fertility conversion for thermo-sensitive cytoplasmic male-sterility wheat, and contribute to the molecular breeding of hybrid wheat in the future.
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Affiliation(s)
- Xingxia Geng
- College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Xiaoxia Wang
- College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Jingchen Wang
- College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Xuetong Yang
- College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Lingli Zhang
- College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Xiyue Song
- College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi, China.
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Two Expansin Genes, AtEXPA4 and AtEXPB5, Are Redundantly Required for Pollen Tube Growth and AtEXPA4 Is Involved in Primary Root Elongation in Arabidopsis thaliana. Genes (Basel) 2021; 12:genes12020249. [PMID: 33578704 PMCID: PMC7916401 DOI: 10.3390/genes12020249] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/30/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
The growth of plant cells is inseparable from relaxation and expansion of cell walls. Expansins are a class of cell wall binding proteins, which play important roles in the relaxation of cell walls. Although there are many members in expansin gene family, the functions of most expansin genes in plant growth and development are still poorly understood. In this study, the functions of two expansin genes, AtEXPA4 and AtEXPB5 were characterized in Arabidopsis thaliana. AtEXPA4 and AtEXPB5 displayed consistent expression patterns in mature pollen grains and pollen tubes, but AtEXPA4 also showed a high expression level in primary roots. Two single mutants, atexpa4 and atexpb5, showed normal reproductive development, whereas atexpa4atexpb5 double mutant was defective in pollen tube growth. Moreover, AtEXPA4 overexpression enhanced primary root elongation, on the contrary, knocking out AtEXPA4 made the growth of primary root slower. Our results indicated that AtEXPA4 and AtEXPB5 were redundantly involved in pollen tube growth and AtEXPA4 was required for primary root elongation.
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Hepler NK, Bowman A, Carey RE, Cosgrove DJ. Expansin gene loss is a common occurrence during adaptation to an aquatic environment. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:666-680. [PMID: 31627246 DOI: 10.1111/tpj.14572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/24/2019] [Accepted: 10/07/2019] [Indexed: 05/15/2023]
Abstract
Expansins comprise a superfamily of plant cell wall loosening proteins that can be divided into four individual families (EXPA, EXPB, EXLA and EXLB). Aside from inferred roles in a variety of plant growth and developmental traits, little is known regarding the function of specific expansin clades, for which there are at least 16 in flowering plants (angiosperms); however, there is evidence to suggest that some expansins have cell-specific functions, in root hair and pollen tube development, for example. Recently, two duckweed genomes have been sequenced (Spirodela polyrhiza strains 7498 and 9509), revealing significantly reduced superfamily sizes. We hypothesized that there would be a correlation between expansin loss and morphological reductions seen among highly adapted aquatic species. In order to provide an answer to this question, we characterized the expansin superfamilies of the greater duckweed Spirodela, the marine eelgrass Zostera marina and the bladderwort Utricularia gibba. We discovered rampant expansin gene and clade loss among the three, including a complete absence of the EXLB family and EXPA-VII. The most convincing correlation between morphological reduction and expansin loss was seen for Utricularia and Spirodela, which both lack root hairs and the root hair expansin clade EXPA-X. Contrary to the pattern observed in other species, four Utricularia expansins failed to branch within any clade, suggesting that they may be the result of neofunctionalization. Last, an expansin clade previously discovered only in eudicots was identified in Spirodela, allowing us to conclude that the last common ancestor of monocots and eudicots contained a minimum of 17 expansins.
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Affiliation(s)
- Nathan K Hepler
- Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Alexa Bowman
- Program in Biochemistry and Molecular Biology, Lebanon Valley College, 101 N. College Ave., Annville, PA, 17003, USA
| | - Robert E Carey
- Department of Biology, Lebanon Valley College, 101 N. College Ave., Annville, PA, 17003, USA
| | - Daniel J Cosgrove
- Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Biology, The Pennsylvania State University, University Park, PA, 16802, USA
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Zhang Y, Wang Y, Ye D, Xing J, Duan L, Li Z, Zhang M. Ethephon-regulated maize internode elongation associated with modulating auxin and gibberellin signal to alter cell wall biosynthesis and modification. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 290:110196. [PMID: 31779899 DOI: 10.1016/j.plantsci.2019.110196] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 07/18/2019] [Accepted: 07/20/2019] [Indexed: 05/12/2023]
Abstract
Ethephon efficiently regulates plant growth to modulate the maize (Zea mays L.) stalk strength and yield potential, yet there is little information on how ethylene governs a specific cellular response for altering internode elongation. Here, the internode elongation kinetics, cell morphological and physiological properties and transcript expression patterns were investigated in the ethephon-treated elongating internode. Ethephon decreased the internode elongation rate, shortened the effective elongation duration, and advanced the growth process. Ethephon regulated the expression patterns of expansin and secondary cell wall-associated cellulose synthase genes to alter cell size. Moreover, ethephon increased the activities and transcripts level of phenylalanine ammonia-lyase and peroxidase, which contributed to lignin accumulation. Otherwise, ethephon-boosted ethylene evolution activated ethylene signal and increased ZmGA2ox3 and ZmGA2ox10 transcript levels while down-regulating ZmPIN1a, ZmPIN4 and ZmGA3ox1 transcript levels, which led to lower accumulation of gibberellins and auxin. In addition, transcriptome profiles confirmed previous results and identified several transcription factors that are involved in the ethephon-modulated transcriptional regulation of cell wall biosynthesis and modification and responses to ethylene, gibberellins and auxin. These results indicated that ethylene-modulated auxin and gibberellins signaling mediated the transcriptional operation of cell wall modification to regulate cell elongation in the ethephon-treated maize internode.
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Affiliation(s)
- Yushi Zhang
- Engineering Research Center of Plant Growth Regulator, Ministry of Education, Key Laboratory of Farming System, Ministry of Agriculture of China, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Yubin Wang
- Engineering Research Center of Plant Growth Regulator, Ministry of Education, Key Laboratory of Farming System, Ministry of Agriculture of China, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Delian Ye
- College of Crop Science, Fujian Agriculture and Forestry University, Fujian, 350002, China
| | - Jiapeng Xing
- Engineering Research Center of Plant Growth Regulator, Ministry of Education, Key Laboratory of Farming System, Ministry of Agriculture of China, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Liusheng Duan
- Engineering Research Center of Plant Growth Regulator, Ministry of Education, Key Laboratory of Farming System, Ministry of Agriculture of China, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Zhaohu Li
- Engineering Research Center of Plant Growth Regulator, Ministry of Education, Key Laboratory of Farming System, Ministry of Agriculture of China, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Mingcai Zhang
- Engineering Research Center of Plant Growth Regulator, Ministry of Education, Key Laboratory of Farming System, Ministry of Agriculture of China, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China.
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Crosstalk between Brassinosteroids and Ethylene during Plant Growth and under Abiotic Stress Conditions. Int J Mol Sci 2018; 19:ijms19103283. [PMID: 30360451 PMCID: PMC6214044 DOI: 10.3390/ijms19103283] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/19/2018] [Accepted: 10/20/2018] [Indexed: 12/26/2022] Open
Abstract
Plant hormones through signaling networks mutually regulate several signaling and metabolic systems essential for both plant development and plant responses to different environmental stresses. Extensive research has enabled the main effects of all known phytohormones classes to be identified. Therefore, it is now possible to investigate the interesting topic of plant hormonal crosstalk more fully. In this review, we focus on the role of brassinosteroids and ethylene during plant growth and development especially flowering, ripening of fruits, apical hook development, and root and shoot growth. As well as it summarizes their interaction during various abiotic stress conditions.
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Li Y, Tu L, Pettolino FA, Ji S, Hao J, Yuan D, Deng F, Tan J, Hu H, Wang Q, Llewellyn DJ, Zhang X. GbEXPATR, a species-specific expansin, enhances cotton fibre elongation through cell wall restructuring. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:951-63. [PMID: 26269378 DOI: 10.1111/pbi.12450] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 05/08/2015] [Accepted: 05/26/2015] [Indexed: 05/18/2023]
Abstract
Cotton provides us the most important natural fibre. High fibre quality is the major goal of cotton breeding, and introducing genes conferring longer, finer and stronger fibre from Gossypium barbadense to Gossypium hirsutum is an important breeding strategy. We previously analysed the G. barbadense fibre development mechanism by gene expression profiling and found two homoeologous fibre-specific α-expansins from G. barbadense, GbEXPA2 and GbEXPATR. GbEXPA2 (from the DT genome) is a classical α-expansin, while its homoeolog, GbEXPATR (AT genome), encodes a truncated protein lacking the normal C-terminal polysaccharide-binding domain of other α-expansins and is specifically expressed in G. barbadense. Silencing EXPA in G. hirsutum induced shorter fibres with thicker cell walls. GbEXPA2 overexpression in G. hirsutum had no effect on mature fibre length, but produced fibres with a slightly thicker wall and increased crystalline cellulose content. Interestingly, GbEXPATR overexpression resulted in longer, finer and stronger fibres coupled with significantly thinner cell walls. The longer and thinner fibre was associated with lower expression of a number of secondary wall-associated genes, especially chitinase-like genes, and walls with lower cellulose levels but higher noncellulosic polysaccharides which advocated that a delay in the transition to secondary wall synthesis might be responsible for better fibre. In conclusion, we propose that α-expansins play a critical role in fibre development by loosening the cell wall; furthermore, a truncated form, GbEXPATR, has a more dramatic effect through reorganizing secondary wall synthesis and metabolism and should be a candidate gene for developing G. hirsutum cultivars with superior fibre quality.
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Affiliation(s)
- Yang Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Lili Tu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Filomena A Pettolino
- Commonwealth Scientific and Industrial Research Organization (CSIRO), Plant Industry, Canberra, ACT, Australia
| | - Shengmei Ji
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Juan Hao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Daojun Yuan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Fenglin Deng
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jiafu Tan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Haiyan Hu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Qing Wang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Danny J Llewellyn
- Commonwealth Scientific and Industrial Research Organization (CSIRO), Plant Industry, Canberra, ACT, Australia
| | - Xianlong Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, China
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Bergonci T, Silva-Filho MC, Moura DS. Antagonistic relationship between AtRALF1 and brassinosteroid regulates cell expansion-related genes. PLANT SIGNALING & BEHAVIOR 2014; 9:e976146. [PMID: 25482784 PMCID: PMC4621977 DOI: 10.4161/15592324.2014.976146] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 08/04/2014] [Accepted: 08/04/2014] [Indexed: 05/26/2023]
Abstract
Rapid alkalinization factor (RALF) is a peptide signal that plays a role in plant cell expansion. We have recently proposed that AtRALF1 negatively regulates root cell elongation and lateral root formation by opposing the effects of brassinosteroid (BR). We reported 6 AtRALF1-inducible cell wall-related genes and 2 P450 monooxygenase -encoding genes involved in the BR biosynthetic pathway. The AtRALF1-inducible genes implicated in cell wall remodeling were not downregulated by brassinolide (BL) treatment alone; their induction was only compromised following simultaneous treatment with AtRALF1 and BL. We further examined the cell wall-remodeling gene EXPANSIN A5 (AtEXPA5), which is upregulated by BL and has been shown to positively affect root cell elongation. Herein, we report that AtEXPA5 expression is downregulated by AtRALF1 in a dose-dependent manner in the roots and hypocotyls of Arabidopsis plants. AtEXPA5 is also downregulated in plants that overexpress AtRALF1, and it is upregulated in plants in which the AtRALF1 gene is partially silenced. The AtRALF1 peptide is also able to repress AtEXPA5 induction following a pre-treatment with BL. A schematic diagram showing the gene regulatory network connecting the recently reported genes with the regulation of cell expansion by AtEXPA5 is presented.
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Affiliation(s)
- Tábata Bergonci
- Laboratório de Bioquímica de Proteínas; Departamento de Ciências Biológicas; Escola Superior de Agricultura Luiz de Queiroz; Universidade de São Paulo (ESALQ/USP); Piracicaba, SP, Brazil
| | - Marcio C Silva-Filho
- Laboratório de Biologia Molecular de Plantas; Departamento de Genética; Escola Superior de Agricultura Luiz de Queiroz; Universidade de São Paulo (ESALQ/USP); Piracicaba, SP, Brazil
| | - Daniel S Moura
- Laboratório de Bioquímica de Proteínas; Departamento de Ciências Biológicas; Escola Superior de Agricultura Luiz de Queiroz; Universidade de São Paulo (ESALQ/USP); Piracicaba, SP, Brazil
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