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Welsch R, Touraev A, Palme K. Small molecules mediate cellular reprogramming across two kingdoms. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:7645-7647. [PMID: 34865113 DOI: 10.1093/jxb/erab493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The fertilized egg is the single totipotent cell from which multicellular organisms arise through the processes of cell division and differentiation. While animals typically lose their capacity to redifferentiate cells that are already fully differentiated, plant cells are thought to remain totipotent (Su et al., 2020). Every gardener knows well that plants can regenerate a full array of plant tissues from already differentiated organs. This also seems to be true for single plant cells such as protoplasts, which, under proper in vitro culture conditions, served as the initial source for generation of transgenic plants (Skoog and Miller, 1957; Birnbaum and Sánchez Alvarado, 2008). However, the mechanisms behind the totipotency of plant cells remain elusive, with the exception of the knowledge that the developmental fate of regenerating tissues can be directed by the ratio of two plant hormones, auxin and cytokinin (Skoog and Miller, 1957).
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Affiliation(s)
- Ralf Welsch
- Institute of Biology II, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
- ScreenSYS GmbH, Engesserstr. 4, D-79108 Freiburg, Germany
| | - Alisher Touraev
- National Center for Knowledge and Innovation in Agriculture, Ministry of Agriculture of the Republic of Uzbekistan, Tashkent region, Universitetskaya str. 2, The Republic of Uzbekistan
| | - Klaus Palme
- Institute of Biology II, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
- ScreenSYS GmbH, Engesserstr. 4, D-79108 Freiburg, Germany
- BIOSS Center for Biological Signaling Studies, Albert-Ludwigs-University of Freiburg, Schänzlestrasse 1, D-79104 Freiburg, Germany
- Sino-German Joint Research Center on Agricultural Biology, College of Life Sciences, Shandong Agricultural University, Daizong Street 61, Tai'an, 271018, China
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Zhang C, He M, Wang S, Chu L, Wang C, Yang N, Ding G, Cai H, Shi L, Xu F. Boron deficiency-induced root growth inhibition is mediated by brassinosteroid signalling regulation in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:564-578. [PMID: 33964043 DOI: 10.1111/tpj.15311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 04/23/2021] [Accepted: 05/03/2021] [Indexed: 05/12/2023]
Abstract
Brassinosteroids (BRs) are pivotal phytohormones involved in the control of root development. Boron (B) is an essential micronutrient for plants, and root growth is rapidly inhibited under B deficiency conditions. However, the mechanisms underlying this inhibition are still unclear. Here, we identified BR-related processes underlying B deficiency at the physiological, genetic, molecular/cell biological and transcriptomic levels and found strong evidence that B deficiency can affect BR biosynthesis and signalling, thereby altering root growth. RNA sequencing analysis revealed strong co-regulation between BR-regulated genes and B deficiency-responsive genes. We found that the BR receptor mutants bri1-119 and bri1-301 were more insensitive to decreased B supply, and the gain-of-function mutants bes1-D and pBZR1-bzr1-D exhibited insensitivity to low-B stress. Under B deficiency conditions, exogenous 24-epibrassinolide rescued the inhibition of root growth, and application of the BR biosynthesis inhibitor brassinazole exacerbated this inhibitory effect. The nuclear-localised signal of BES1 was reduced under low-B conditions compared with B sufficiency conditions. We further found that B deficiency hindered the accumulation of brassinolide to downregulate BR signalling and modulate root elongation, which may occur through a reduction in BR6ox1 and BR6ox2 mRNA levels. Taken together, our results reveal a role of BR signalling in root elongation under B deficiency.
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Affiliation(s)
- Cheng Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Mingliang He
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Sheliang Wang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Liuyang Chu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Chuang Wang
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Ningmei Yang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Guangda Ding
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Hongmei Cai
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Lei Shi
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
| | - Fangsen Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
- Microelement Research Center/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
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Starodubtseva A, Kalachova T, Iakovenko O, Stoudková V, Zhabinskii V, Khripach V, Ruelland E, Martinec J, Burketová L, Kravets V. BODIPY Conjugate of Epibrassinolide as a Novel Biologically Active Probe for In Vivo Imaging. Int J Mol Sci 2021; 22:3599. [PMID: 33808421 PMCID: PMC8036458 DOI: 10.3390/ijms22073599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 11/17/2022] Open
Abstract
Brassinosteroids (BRs) are plant hormones of steroid nature, regulating various developmental and adaptive processes. The perception, transport, and signaling of BRs are actively studied nowadays via a wide range of biochemical and genetic tools. However, most of the knowledge about BRs intracellular localization and turnover relies on the visualization of the receptors or cellular compartments using dyes or fluorescent protein fusions. We have previously synthesized a conjugate of epibrassinolide with green fluorescent dye BODIPY (eBL-BODIPY). Here we present a detailed assessment of the compound bioactivity and its suitability as probe for in vivo visualization of BRs. We show that eBL-BODIPY rapidly penetrates epidermal cells of Arabidopsis thaliana roots and after long exposure causes physiological and transcriptomic responses similar to the natural hormone.
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Affiliation(s)
- Anastasiia Starodubtseva
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague, Czech Republic
- Institute of Ecology and Environmental Sciences of Paris, Paris-Est University, UPEC, 94010 Créteil, France
| | - Tetiana Kalachova
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Oksana Iakovenko
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, 02094 Kyiv, Ukraine;
| | - Vera Stoudková
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Vladimir Zhabinskii
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, Kuprevich Str., 5/2, 220141 Minsk, Belarus; (V.Z.); (V.K.)
| | - Vladimir Khripach
- Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, Kuprevich Str., 5/2, 220141 Minsk, Belarus; (V.Z.); (V.K.)
| | - Eric Ruelland
- UMR 7025 CNRS, GEC Génie Enzymatique et Cellulaire, Centre de Recherches, Rue Personne de Roberval, CS 60319, Alliance Sorbonne Universités, Université de Technologie de Compiègne, 60203 Compiègne CEDEX, France;
| | - Jan Martinec
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Lenka Burketová
- Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02 Prague, Czech Republic; (A.S.); (O.I.); (V.S.); (J.M.); (L.B.)
| | - Volodymyr Kravets
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Sciences of Ukraine, 02094 Kyiv, Ukraine;
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5
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Wang Q, Yu F, Xie Q. Balancing growth and adaptation to stress: Crosstalk between brassinosteroid and abscisic acid signaling. PLANT, CELL & ENVIRONMENT 2020; 43:2325-2335. [PMID: 32671865 DOI: 10.1111/pce.13846] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/30/2020] [Accepted: 07/09/2020] [Indexed: 05/07/2023]
Abstract
Plant growth and development are plastic and canadapt to environmental changes. In this process different plant hormones coordinate to modulate plant growth and environmental interactions. In this article, we describe the individual brassinosteroid (BR) and abscisic acid (ABA) signaling pathways, emphasize the specific regulatory mechanisms between ABA and BR responses and discuss how both phytohormones coordinate growth, development and stress responses in plants. BR signaling is essential for plant development, while ABA signaling is activated to ensure plants survive stress. The crosstalk between BR and ABA, especially protein phosphorylation, protein stability control and downstream transcription control of key components of both pathways are discussed in terms of modulating plant development and stress adaptation.
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Affiliation(s)
- Qian Wang
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Feifei Yu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Qi Xie
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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Kandelinskaya OL, Grischenko HR, Кhripach VA, Zhabinskii VN, Kartizhova LE, Shashko YK, Kosmachevskaya OV, Nasybullina EI, Topunov AF. Anabolic/anticatabolic and adaptogenic effects of 24-epibrassinolide on Lupinus angustifolius: Causes and consequences. Steroids 2020; 154:108545. [PMID: 31758963 DOI: 10.1016/j.steroids.2019.108545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/19/2019] [Accepted: 11/14/2019] [Indexed: 11/19/2022]
Abstract
Lupinus angustifolius L. is a legume culture known as a source of valuable feed protein and the N2-fixator for improving soil fertility. However, its low ecological resistance does not allow for a stable yield of the crop. Earlier, we have shown that steroid phytohormone 24-epibrassinolide (EBR) increases the tolerance of lupine to chlorine ions by activating the protective proteins in ripening seeds (such as proteinase inhibitors that prevent protein breakdown) and lectins. Here we investigated the effect of EBR on the functional status of the N2-fixing system in root nodules, protein synthesis in ripening seeds and the resistance of lupine plants to various pathogens. It was found that EBR enhanced the nodulation process, N2-fixing activity of nitrogenase and the accumulation of poly-β-hydroxybutirate in the bacteroides, increased the leghemoglobin content in the nodules as well as the metabolic activity of bacteroides. According to data on the inclusion of 14C-leucine in maturing seed proteins, EBR increased the accumulation of protein in them against the background of a short-term decrease in protein synthesis and its subsequent regeneration to the control level. Gradual inhibition of protein synthesis, characteristic of other legumes, was observed in control variants of lupine. EBR increased lupine resistance to phytopathogenic fungi of Colletotrichum genus and insects of Noctuidae and Scarabaeidae families. We concluded that a more complete implementation of the potential productivity and sustainability of lupine under the action of EBR was achieved due to the anabolic/anti-catabolic effect on the N2 fixation system in root nodules, as well as on protein synthesis in ripening seeds.
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Affiliation(s)
- Olga L Kandelinskaya
- Kuprevich Institute of Experimental Botany of the National Academy of Sciences of Belarus, 220072 Minsk, Akademicheskaya, 27, Belarus.
| | - Helena R Grischenko
- Kuprevich Institute of Experimental Botany of the National Academy of Sciences of Belarus, 220072 Minsk, Akademicheskaya, 27, Belarus
| | - Vladimir A Кhripach
- Institute of Bioorganic Chemistry of the National Academy of Sciences of Belarus, 2200141 Minsk, Kuprevich st, 5/2, Belarus
| | - Vladimir N Zhabinskii
- Institute of Bioorganic Chemistry of the National Academy of Sciences of Belarus, 2200141 Minsk, Kuprevich st, 5/2, Belarus
| | - Lylia E Kartizhova
- Institute of Microbiology of the National Academy of Sciences of Belarus, 2200141 Minsk, Kuprevich st, 2, Belarus
| | - Yuriy K Shashko
- Research and Practical Center of the National Academy of Sciences of Belarus for Arable Farming, 222160 Zhodino, Timiriyazeva, 1, Belarus
| | - Olga V Kosmachevskaya
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Elvira I Nasybullina
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Alexey F Topunov
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
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Guo YF, Shan W, Liang SM, Wu CJ, Wei W, Chen JY, Lu WJ, Kuang JF. MaBZR1/2 act as transcriptional repressors of ethylene biosynthetic genes in banana fruit. PHYSIOLOGIA PLANTARUM 2019; 165:555-568. [PMID: 29704245 DOI: 10.1111/ppl.12750] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 04/14/2018] [Accepted: 04/23/2018] [Indexed: 05/21/2023]
Abstract
Banana fruit (Musa acuminate L.) ripening is a complex genetical process affected by multiple phytohormones and expression of various genes. However, whether plant hormone brassinosteroid (BR) is involved in this process remains obscure. In this work, three genes that encode BR core signaling components brassinazole resistant (BZR) proteins, namely MaBZR1 to MaBZR3, were characterized from banana fruit. MaBZR1-MaBZR3 exhibited both nuclear and cytoplasmic localization and behaved as transcription inhibitors. Expression analysis showed that MaBZR1/2/3 were continuously decreased as fruit ripening proceeded, indicating their negative roles in banana ripening. Moreover, gel shift and transient expression assays demonstrated that MaBZR1/2 could suppress the transcription of ethylene biosynthetic genes, including MaACS1, MaACO13 and MaACO14, which increased gradually during the banana ripening, via specifically binding to CGTGT/CG sequence in their promoters. Importantly, exogenous application of BRs promotes banana ripening, which is presumably due to the accelerated expression of MaACS1 and MaACO13/14, and consequently the ethylene production. Our study indicates that MaBZR1/2 act as transcriptional repressors of ethylene biosynthetic genes during banana fruit ripening.
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Affiliation(s)
- Yu-Fan Guo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Wei Shan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Shu-Min Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Chao-Jie Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Wei Wei
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Jian-Ye Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Wang-Jin Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
| | - Jian-Fei Kuang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticultural Science, South China Agricultural University, Guangzhou, 510642, China
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Wang H, Tang J, Liu J, Hu J, Liu J, Chen Y, Cai Z, Wang X. Abscisic Acid Signaling Inhibits Brassinosteroid Signaling through Dampening the Dephosphorylation of BIN2 by ABI1 and ABI2. MOLECULAR PLANT 2018; 11:315-325. [PMID: 29275167 DOI: 10.1016/j.molp.2017.12.013] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 12/12/2017] [Accepted: 12/15/2017] [Indexed: 05/20/2023]
Abstract
Abscisic acid (ABA) and brassinosteroid (BR) antagonistically regulate many aspects of plant growth and development. Previous physiological studies have revealed that the inhibition of BR signaling by ABA is largely dependent on ABI1 and ABI2. However, the genetic and molecular basis of how ABI1 and ABI2 are involved in inhibiting BR signaling remains unclear. Although it is known that in the BR signaling pathway the ABA-BR crosstalk occurs in the downstream of BR receptor complex but upstream of BIN2 kinase, a negative regulator of BR signaling, the component that acts as the hub to directly mediate their crosstalk remains a big mystery. Here, we found that ABI1 and ABI2 interact with and dephosphorylate BIN2 to regulate its activity toward the phosphorylation of BES1. By in vitro mimicking ABA signal transduction, we found that ABA can promote BIN2 phosphorylation by inhibiting ABI2 through ABA receptors. RNA-sequencing analysis further demonstrated that ABA inhibits BR signaling through the ABA primary signaling components, including its receptors and ABI2, and that ABA and GSK3s co-regulate a common set of stress-responsive genes. Because BIN2 can interact with and phosphorylate SnRK2s to activate its kinase activity, our study also reveals there is a module of PP2Cs-BIN2-SnRK2s in the ABA signaling pathway. Collectively, these findings provide significant insights into how plants balance growth and survival by coordinately regulating the growth-promoting signaling pathway and stress responses under abiotic stresses.
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Affiliation(s)
- Haijiao Wang
- Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jie Tang
- Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jing Liu
- Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jin Hu
- Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jingjing Liu
- State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Yuxiao Chen
- State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Zhenying Cai
- State Key Laboratory of Genetic Engineering, Department of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Xuelu Wang
- Center of Integrative Biology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
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Kohli SK, Handa N, Sharma A, Gautam V, Arora S, Bhardwaj R, Alyemeni MN, Wijaya L, Ahmad P. Combined effect of 24-epibrassinolide and salicylic acid mitigates lead (Pb) toxicity by modulating various metabolites in Brassica juncea L. seedlings. PROTOPLASMA 2018; 255:11-24. [PMID: 28573335 DOI: 10.1007/s00709-017-1124-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 05/12/2017] [Indexed: 05/12/2023]
Abstract
The present study demonstrated the combined effect of 24-epibrassinolide and salicylic acid against lead (Pb, 0.25, 0.50, and 0.75 mM) toxicity in Brassica juncea seedlings. Various parameters including water status, metal uptake, total water- and lipid-soluble antioxidants, metal chelator content (total thiols, protein-bound thiols, and non-protein-bound thiols), phenolic compounds (flavonoids, anthocyanins, and polyphenols), and organic acids were studied in 10-day-old seedlings. Dry matter content and the heavy metal tolerance index were reduced by 42.24 and 52.3%, respectively, in response to Pb treatment. Metal uptake, metal-chelating compounds, phenolic compounds, and organic acids were increased in Pb-treated seedlings as compared to control plants. The treatment of Pb-stressed seedlings with combination of EBL and SA resulted in enhancement of heavy metal tolerance index by 40.07%, water content by 1.84%, and relative water content by 23.45%. The total water- and lipid-soluble antioxidants were enhanced by 21.01 and 2.21%, respectively. In contrast, a significant decline in dry weight, metal uptake, thiol, and polyphenol contents was observed following the application of 24-epibrassinolide and salicylic acid. These observations indicate that Pb treatment has an adverse effect on B. juncea seedlings. However, co-application of 24-epibrassinolide and salicylic acid mitigates the negative effects of Pb, by lowering Pb metal uptake and enhancing the heavy metal tolerance index, water content, relative water content, antioxidative capacities, phenolic content, and organic acid levels.
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Affiliation(s)
- Sukhmeen Kaur Kohli
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, India
| | - Neha Handa
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, India
| | - Anket Sharma
- Department of Botany, DAV University, Sarmastpur, Jalandhar, 144012, India
| | - Vandana Gautam
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, India
| | - Saroj Arora
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, India
| | - Renu Bhardwaj
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, 143005, India.
| | - Mohammed Nasser Alyemeni
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Leonard Wijaya
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Parvaiz Ahmad
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
- Department of Botany, S.P. College, Srinagar, Jammu and Kashmir, 190001, India.
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Cavaiuolo M, Cocetta G, Spadafora ND, Müller CT, Rogers HJ, Ferrante A. Gene expression analysis of rocket salad under pre-harvest and postharvest stresses: A transcriptomic resource for Diplotaxis tenuifolia. PLoS One 2017; 12:e0178119. [PMID: 28558066 PMCID: PMC5448768 DOI: 10.1371/journal.pone.0178119] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/07/2017] [Indexed: 11/25/2022] Open
Abstract
Diplotaxis tenuifolia L. is of important economic value in the fresh-cut industry for its nutraceutical and sensorial properties. However, information on the molecular mechanisms conferring tolerance of harvested leaves to pre- and postharvest stresses during processing and shelf-life have never been investigated. Here, we provide the first transcriptomic resource of rocket by de novo RNA sequencing assembly, functional annotation and stress-induced expression analysis of 33874 transcripts. Transcriptomic changes in leaves subjected to commercially-relevant pre-harvest (salinity, heat and nitrogen starvation) and postharvest stresses (cold, dehydration, dark, wounding) known to affect quality and shelf-life were analysed 24h after stress treatment, a timing relevant to subsequent processing of salad leaves. Transcription factors and genes involved in plant growth regulator signaling, autophagy, senescence and glucosinolate metabolism were the most affected by the stresses. Hundreds of genes with unknown function but uniquely expressed under stress were identified, providing candidates to investigate stress responses in rocket. Dehydration and wounding had the greatest effect on the transcriptome and different stresses elicited changes in the expression of genes related to overlapping groups of hormones. These data will allow development of approaches targeted at improving stress tolerance, quality and shelf-life of rocket with direct applications in the fresh-cut industries.
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Affiliation(s)
- Marina Cavaiuolo
- Department of Agricultural and Environmental Sciences, Università degli Studi di Milano, Milano, Italy
| | - Giacomo Cocetta
- Department of Agricultural and Environmental Sciences, Università degli Studi di Milano, Milano, Italy
| | | | | | - Hilary J. Rogers
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Antonio Ferrante
- Department of Agricultural and Environmental Sciences, Università degli Studi di Milano, Milano, Italy
- * E-mail:
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11
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Suza WP, Chappell J. Spatial and temporal regulation of sterol biosynthesis in Nicotiana benthamiana. PHYSIOLOGIA PLANTARUM 2016; 157:120-34. [PMID: 26671544 DOI: 10.1111/ppl.12413] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 11/11/2015] [Accepted: 11/16/2015] [Indexed: 05/22/2023]
Abstract
Nicotiana benthamiana was used as a model to investigate the spatial and developmental relationship between sterol synthesis rates and sterol content in plants. Stigmasterol levels were approximately twice the level in roots as that found in aerial tissues, while its progenitor sterol sitosterol was the inverse. When incorporation of radiolabeled precursors into sterols was used as measure of in vivo synthesis rates, acetate incorporation was similar across all tissue types, but approximately twofold greater in roots than any other tissue. In contrast, mevalonate incorporation exhibited the greatest differential with the rate of incorporation in roots approximately one-tenth that in apical shoots. Similar to acetate, incorporation of farnesol was higher in roots but remained fairly constant in aerial tissues, suggesting less regulation of the downstream sterol biosynthetic steps. Consistent with the precursor incorporation data, analysis of gene transcript and measurements of putative rate-limiting enzyme activities for 3-hydroxy-3-methylglutaryl-coenzyme A synthase (EC 2.3.3.10) and reductase (EC 1.1.1.34) showed the greatest modulation of levels, while the activity levels for isopentenyl diphosphate isomerase (EC 5.3.3.2) and prenyltransferases (EC 2.5.1.10 and EC 2.5.1.1) also exhibited a strong but moderate correlation with the development age of the aerial tissues of the plants. Overall, the data suggest a multitude of means from transcriptional to posttranslational control affecting sterol biosynthesis and accumulation across an entire plant, and point to some particular control points that might be manipulated using molecular genetic approaches to better probe the role of sterols in plant growth and development.
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Affiliation(s)
- Walter P Suza
- Department of Agronomy, Iowa State University, Ames, IA, 50011-1010, USA
| | - Joe Chappell
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY, 40546-0312, USA
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12
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Janeczko A, Gruszka D, Pociecha E, Dziurka M, Filek M, Jurczyk B, Kalaji HM, Kocurek M, Waligórski P. Physiological and biochemical characterisation of watered and drought-stressed barley mutants in the HvDWARF gene encoding C6-oxidase involved in brassinosteroid biosynthesis. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 99:126-41. [PMID: 26752435 DOI: 10.1016/j.plaphy.2015.12.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Revised: 11/30/2015] [Accepted: 12/04/2015] [Indexed: 05/02/2023]
Abstract
Brassinosteroids (BR) are plant steroid hormones that were discovered more than thirty years ago, but their physiological function has yet to be fully explained. The aim of the study was to answer the question of whether/how disturbances in the production of BR in barley affects the plant's metabolism and development under conditions of optimal watering and drought. Mutants with an impaired production of BR are one of the best tools in research aimed at understanding the mechanisms of action of these hormones. The study used barley cultivars with a normal BR synthesis (wild type) and semi-dwarf allelic mutants with an impaired activity of C6-oxidase (mutation in HvDWARF), which resulted in a decreased BR synthesis. Half of the plants were subjected to drought stress in the seedling stage and the other half were watered optimally. Plants with impaired BR production were characterised by a lower height and developmental retardation. Under both optimal watering and drought, BR synthesis disorders caused the reduced production of ABA and cytokinins, but not auxins. The BR mutants also produced less osmoprotectant (proline). The optimally watered and drought-stressed mutants accumulated less sucrose, which was accompanied by changes in the production of other soluble sugars. The increased content of fructooligosaccharide (kestose) in optimally watered mutants would suggest that BR is a negative regulator of kestose production. The decreased level of nystose in the drought-stressed mutants also suggests BR involvement in the regulation of the production of this fructooligosaccharide. The accumulation of the transcripts of genes associated with stress response (hsp90) was lower in the watered and drought-stressed BR-deficient mutants. In turn, the lower efficiency of photosystem II and the net photosynthetic rate in mutants was revealed only under drought conditions. The presented research allows for the physiological and biochemical traits of two BR-barley mutants to be characterised, which helps BR function to be understood. The knowledge can also be a good starting point for some breeding companies that are interested in introducing new semi-dwarf barley cultivars.
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Affiliation(s)
- Anna Janeczko
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239 Krakow, Poland.
| | - Damian Gruszka
- Department of Genetics, Faculty of Biology and Environment Protection, University of Silesia, Jagiellonska 28, 40-032 Katowice, Poland
| | - Ewa Pociecha
- Department of Plant Physiology, University of Agriculture in Krakow, Podłużna 3, 30-239 Krakow, Poland
| | - Michał Dziurka
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239 Krakow, Poland
| | - Maria Filek
- Institute of Biology, Pedagogical University, Podchorążych 2, 30-084 Krakow, Poland
| | - Barbara Jurczyk
- Department of Plant Physiology, University of Agriculture in Krakow, Podłużna 3, 30-239 Krakow, Poland
| | - Hazem M Kalaji
- Department of Plant Physiology, Faculty of Agriculture and Biology, Warsaw Agricultural University WULS-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
| | - Maciej Kocurek
- Institute of Biology, The Jan Kochanowski University, Świętokrzyska 15, 25-406 Kielce, Poland
| | - Piotr Waligórski
- The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239 Krakow, Poland
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Shi C, Qi C, Ren H, Huang A, Hei S, She X. Ethylene mediates brassinosteroid-induced stomatal closure via Gα protein-activated hydrogen peroxide and nitric oxide production in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:280-301. [PMID: 25754244 DOI: 10.1111/tpj.12815] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 02/14/2015] [Accepted: 02/23/2015] [Indexed: 05/07/2023]
Abstract
Brassinosteroids (BRs) are essential for plant growth and development; however, whether and how they promote stomatal closure is not fully clear. In this study, we report that 24-epibrassinolide (EBR), a bioactive BR, induces stomatal closure in Arabidopsis (Arabidopsis thaliana) by triggering a signal transduction pathway including ethylene synthesis, the activation of Gα protein, and hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) production. EBR initiated a marked rise in ethylene, H(2)O(2) and NO levels, necessary for stomatal closure in the wild type. These effects were abolished in mutant bri1-301, and EBR failed to close the stomata of gpa1 mutants. Next, we found that both ethylene and Gα mediate the inductive effects of EBR on H(2)O(2) and NO production. EBR-triggered H(2)O(2) and NO accumulation were canceled in the etr1 and gpa1 mutants, but were strengthened in the eto1-1 mutant and the cGα line (constitutively overexpressing the G protein α-subunit AtGPA1). Exogenously applied H(2)O(2) or sodium nitroprusside (SNP) rescued the defects of etr1-3 and gpa1 or etr1 and gpa1 mutants in EBR-induced stomatal closure, whereas the stomata of eto1-1/AtrbohF and cGα/AtrbohF or eto1-1/nia1-2 and cGα/nia1-2 constructs had an analogous response to H(2)O(2) or SNP as those of AtrbohF or Nia1-2 mutants. Moreover, we provided evidence that Gα plays an important role in the responses of guard cells to ethylene. Gα activator CTX largely restored the lesion of the etr1-3 mutant, but ethylene precursor ACC failed to rescue the defects of gpa1 mutants in EBR-induced stomatal closure. Lastly, we demonstrated that Gα-activated H(2)O(2) production is required for NO synthesis. EBR failed to induce NO synthesis in mutant AtrbohF, but it led to H(2)O(2) production in mutant Nia1-2. Exogenously applied SNP rescued the defect of AtrbohF in EBR-induced stomatal closure, but H(2)O(2) did not reverse the lesion of EBR-induced stomatal closure in Nia1-2. Together, our results strongly suggest a signaling pathway in which EBR induces ethylene synthesis, thereby activating Gα, and then promotes AtrbohF-dependent H(2)O(2) production and subsequent Nia1-catalyzed NO accumulation, and finally closes stomata.
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Affiliation(s)
- Chenyu Shi
- School of Life Sciences, Shaanxi Normal University, Xi'an, 710062, China; School of Chemistry and Bioengineering, Hechi University, Yizhou, 546300, China
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Mills-Lujan K, Andrews DL, Chou CW, Deom CM. The roles of phosphorylation and SHAGGY-like protein kinases in geminivirus C4 protein induced hyperplasia. PLoS One 2015; 10:e0122356. [PMID: 25815729 PMCID: PMC4376871 DOI: 10.1371/journal.pone.0122356] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 02/16/2015] [Indexed: 12/26/2022] Open
Abstract
Even though plant cells are highly plastic, plants only develop hyperplasia under very specific abiotic and biotic stresses, such as when exposed to pathogens like Beet curly top virus (BCTV). The C4 protein of BCTV is sufficient to induce hyperplasia and alter Arabidopsis development. It was previously shown that C4 interacts with two Arabidopsis Shaggy-like protein kinases, AtSK21 and 23, which are negative regulators of brassinosteroid (BR) hormone signaling. Here we show that the C4 protein interacts with five additional AtSK family members. Bikinin, a competitive inhibitor of the seven AtSK family members that interact with C4, induced hyperplasia similar to that induced by the C4 protein. The Ser49 residue of C4 was found to be critical for C4 function, since: 1) mutagenesis of Ser49 to Ala abolished the C4-induced phenotype, abolished C4/AtSK interactions, and resulted in a mutant protein that failed to induce changes in the BR signaling pathway; 2) Ser49 is phosphorylated in planta; and 3) plant-encoded AtSKs must be catalytically active to interact with C4. A C4 N-myristoylation site mutant that does not localize to the plasma membrane and does not induce a phenotype, retained the ability to bind AtSKs. Taken together, these results suggest that plasma membrane associated C4 interacts with and co-opts multiple AtSKs to promote its own phosphorylation and activation to subsequently compromise cell cycle control.
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Affiliation(s)
- Katherine Mills-Lujan
- Department of Plant Pathology, The University of Georgia, Athens, Georgia, United States of America
| | - David L. Andrews
- Department of Plant Pathology, The University of Georgia, Athens, Georgia, United States of America
| | - Chau-wen Chou
- Department of Chemistry, Proteomics and Mass Spectrometry Core Facility, The University of Georgia, Athens, Georgia, United States of America
| | - C. Michael Deom
- Department of Plant Pathology, The University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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González A, Contreras RA, Zúiga G, Moenne A. Oligo-carrageenan kappa-induced reducing redox status and activation of TRR/TRX system increase the level of indole-3-acetic acid, gibberellin A3 and trans-zeatin in Eucalyptus globulus trees. Molecules 2014; 19:12690-8. [PMID: 25140447 PMCID: PMC6272046 DOI: 10.3390/molecules190812690] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 08/13/2014] [Accepted: 08/15/2014] [Indexed: 12/17/2022] Open
Abstract
Eucalyptus globulus trees treated with oligo-carrageenan (OC) kappa showed an increase in NADPH, ascorbate and glutathione levels and activation of the thioredoxin reductase (TRR)/thioredoxin (TRX) system which enhance photosynthesis, basal metabolism and growth. In order to analyze whether the reducing redox status and the activation of thioredoxin reductase (TRR)/thioredoxin (TRX) increased the level of growth-promoting hormones, trees were treated with water (control), with OC kappa, or with inhibitors of ascorbate synthesis, lycorine, glutathione synthesis, buthionine sulfoximine (BSO), NADPH synthesis, CHS-828, and thioredoxin reductase activity, auranofine, and with OC kappa, and cultivated for four additional months. Eucalyptus trees treated with OC kappa showed an increase in the levels of the auxin indole 3-acetic acid (IAA), gibberellin A3 (GA3) and the cytokinin trans-zeatin (t-Z) as well as a decrease in the level of the brassinosteroid epi-brassinolide (EB). In addition, treatment with lycorine, BSO, CHS-828 and auranofine inhibited the increase in IAA, GA3 and t-Z as well as the decrease in EB levels. Thus, the reducing redox status and the activation of TRR/TRX system induced by OC kappa increased the levels of IAA, GA3 and t-Z levels determining, at least in part, the stimulation of growth in Eucalyptus trees.
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Affiliation(s)
- Alberto González
- Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile.
| | - Rodrigo A Contreras
- Plant Physiology and Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile.
| | - Gustavo Zúiga
- Plant Physiology and Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile.
| | - Alejandra Moenne
- Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, 9170022 Santiago, Chile.
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Nigam D, Kavita P, Tripathi RK, Ranjan A, Goel R, Asif M, Shukla A, Singh G, Rana D, Sawant SV. Transcriptome dynamics during fibre development in contrasting genotypes of Gossypium hirsutum L. PLANT BIOTECHNOLOGY JOURNAL 2014; 12:204-218. [PMID: 24119257 DOI: 10.1111/pbi.12129] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/29/2013] [Accepted: 09/03/2013] [Indexed: 06/02/2023]
Abstract
Understanding the contribution of genetic background in fibre quality traits is important for the development of future cotton varieties with superior fibre quality. We used Affymetrix microarray (Santa Clara, CA) and Roche 454 GSFLX (Branford, CT) for comparative transcriptome analysis between two superior and three inferior genotypes at six fibre developmental stages. Microarray-based analysis of variance (ANOVA) for 89 microarrays encompassing five contrasting genotypes and six developmental stages suggests that the stages of the fibre development have a more pronounced effect on the differentially expressed genes (DEGs) than the genetic background of genotypes. Superior genotypes showed enriched activity of cell wall enzymes, such as pectin methyl esterase, at early elongation stage, enriched metabolic activities such as lipid, amino acid and ribosomal protein subunits at peak elongation, and prolonged combinatorial regulation of brassinosteroid and auxin at later stages. Our efforts on transcriptome sequencing were focused on changes in gene expression at 25 DPA. Transcriptome sequencing resulted in the generation of 475 658 and 429 408 high-quality reads from superior and inferior genotypes, respectively. A total of 24 609 novel transcripts were identified manually for Gossypium hirsutum with no hits in NCBI 'nr' database. Gene ontology analyses showed that the genes for ribosome biogenesis, protein transport and fatty acid biosynthesis were over-represented in superior genotype, whereas salt stress, abscisic acid stimuli and water deprivation leading to the increased proteolytic activity were more pronounced in inferior genotype.
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Affiliation(s)
- Deepti Nigam
- Plant Molecular Biology Laboratory, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, India
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17
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Böttcher C, Burbidge CA, Boss PK, Davies C. Interactions between ethylene and auxin are crucial to the control of grape (Vitis vinifera L.) berry ripening. BMC PLANT BIOLOGY 2013; 13:222. [PMID: 24364881 PMCID: PMC3878033 DOI: 10.1186/1471-2229-13-222] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 12/20/2013] [Indexed: 05/18/2023]
Abstract
BACKGROUND Fruit development is controlled by plant hormones, but the role of hormone interactions during fruit ripening is poorly understood. Interactions between ethylene and the auxin indole-3-acetic acid (IAA) are likely to be crucial during the ripening process, since both hormones have been shown to be implicated in the control of ripening in a range of different fruit species. RESULTS Grapevine (Vitis vinifera L.) homologues of the TRYPTOPHAN AMINOTRANSFERASE RELATED (TAR) and YUCCA families, functioning in the only characterized pathway of auxin biosynthesis, were identified and the expression of several TAR genes was shown to be induced by the pre-ripening application of the ethylene-releasing compound Ethrel. The induction of TAR expression was accompanied by increased IAA and IAA-Asp concentrations, indicative of an upregulation of auxin biosynthesis and conjugation. Exposure of ex planta, pre-ripening berries to the ethylene biosynthesis inhibitor aminoethoxyvinylglycine resulted in decreased IAA and IAA-Asp concentrations. The delayed initiation of ripening observed in Ethrel-treated berries might therefore represent an indirect ethylene effect mediated by increased auxin concentrations. During berry development, the expression of three TAR genes and one YUCCA gene was upregulated at the time of ripening initiation and/or during ripening. This increase in auxin biosynthesis gene expression was preceded by high expression levels of the ethylene biosynthesis genes 1-aminocyclopropane-1-carboxylate synthase and 1-aminocyclopropane-1-carboxylate oxidase. CONCLUSIONS In grape berries, members of both gene families involved in the two-step pathway of auxin biosynthesis are expressed, suggesting that IAA is produced through the combined action of TAR and YUCCA proteins in developing berries. The induction of TAR expression by Ethrel applications and the developmental expression patterns of auxin and ethylene biosynthesis genes indicate that elevated concentrations of ethylene prior to the initiation of ripening might lead to an increased production of IAA, suggesting a complex involvement of this auxin and its conjugates in grape berry ripening.
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Affiliation(s)
| | | | - Paul K Boss
- CSIRO Plant Industry, PO Box 350, Glen Osmond, SA 5064, Australia
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Vriet C, Russinova E, Reuzeau C. From squalene to brassinolide: the steroid metabolic and signaling pathways across the plant kingdom. MOLECULAR PLANT 2013; 6:1738-57. [PMID: 23761349 DOI: 10.1093/mp/sst096] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The plant steroid hormones, brassinosteroids (BRs), and their precursors, phytosterols, play major roles in plant growth, development, and stress tolerance. Here, we review the impressive progress made during recent years in elucidating the components of the sterol and BR metabolic and signaling pathways, and in understanding their mechanism of action in both model plants and crops, such as Arabidopsis and rice. We also discuss emerging insights into the regulations of these pathways, their interactions with other hormonal pathways and multiple environmental signals, and the putative nature of sterols as signaling molecules.
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Affiliation(s)
- Cécile Vriet
- CropDesign NV, a BASF Plant Science Company, 9052 Gent, Belgium
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Krost C, Petersen R, Lokan S, Brauksiepe B, Braun P, Schmidt ER. Evaluation of the hormonal state of columnar apple trees (Malus x domestica) based on high throughput gene expression studies. PLANT MOLECULAR BIOLOGY 2013; 81:211-20. [PMID: 23306528 DOI: 10.1007/s11103-012-9992-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 11/23/2012] [Indexed: 05/23/2023]
Abstract
The columnar phenotype of apple trees (Malus x domestica) is characterized by a compact growth habit with fruit spurs instead of lateral branches. These properties provide significant economic advantages by enabling high density plantings. The columnar growth results from the presence of a dominant allele of the gene Columnar (Co) located on chromosome 10 which can appear in a heterozygous (Co/co) or homozygous (Co/Co) state. Although two deep sequencing approaches could shed some light on the transcriptome of columnar shoot apical meristems (SAMs), the molecular mechanisms of columnar growth are not yet elaborated. Since the influence of phytohormones is believed to have a pivotal role in the establishment of the phenotype, we performed RNA-Seq experiments to study genes associated with hormone homeostasis and clearly affected by the presence of Co. Our results provide a molecular explanation for earlier findings on the hormonal state of columnar apple trees. Additionally, they allow hypotheses on how the columnar phenotype might develop. Furthermore, we show a statistically approved enrichment of differentially regulated genes on chromosome 10 in the course of validating RNA-Seq results using additional gene expression studies.
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Affiliation(s)
- Clemens Krost
- Department of Molecular Genetics, University of Mainz, 55128 Mainz, Germany.
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21
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Garg R, Tyagi AK, Jain M. Microarray analysis reveals overlapping and specific transcriptional responses to different plant hormones in rice. PLANT SIGNALING & BEHAVIOR 2012; 7:951-6. [PMID: 22827941 PMCID: PMC3474693 DOI: 10.4161/psb.20910] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Hormones exert pleiotropic effects on plant growth and development throughout the life cycle. Many of these effects are mediated at molecular level via altering gene expression. In this study, we investigated the exogenous effect of plant hormones, including auxin, cytokinin, abscisic acid, ethylene, salicylic acid and jasmonic acid, on the transcription of rice genes at whole genome level using microarray. Our analysis identified a total of 4171 genes involved in several biological processes, whose expression was altered significantly in the presence of different hormones. Further, 28% of these genes exhibited overlapping transcriptional responses in the presence of any two hormones, indicating crosstalk among plant hormones. In addition, we identified genes showing only a particular hormone-specific response, which can be used as hormone-specific markers. The results of this study will facilitate further studies in hormone biology in rice.
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Yuldashev R, Avalbaev A, Bezrukova M, Vysotskaya L, Khripach V, Shakirova F. Cytokinin oxidase is involved in the regulation of cytokinin content by 24-epibrassinolide in wheat seedlings. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2012; 55:1-6. [PMID: 22480990 DOI: 10.1016/j.plaphy.2012.03.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 03/05/2012] [Indexed: 05/05/2023]
Abstract
Fast and stable 2-fold accumulation of cytokinins (CKs) was detected initially in roots and then in shoots of 4-day-old wheat (Triticum aestivum L.) seedlings in the course of their treatment with 0.4μM 24-epibrassinolide (EBR). Elevated cytokinin level has been maintained only in the presence of EBR, while the hormone removal has led to return of cytokinin concentration to the control level initially in the roots and then in the shoots. EBR-induced accumulation of cytokinins was accompanied by inhibition of both cytokinin oxidase (CKX) (cytokinin oxidase/dehydrogenase, EC 1.5.99.12) activity and expression of the gene coding for this enzyme, and on the contrary the decline in CKs level resulted in increase in these characteristics up to the control level in roots and then in shoots. Sharp accumulation of cytokinin O-glucosides has been discovered in response to EBR-treatment suggesting fast EBR-induced activation of production of cytokinins, which excessive amounts were transferred into the storage forms. The obtained data provide evidence for the involvement of EBR in regulation of cytokinin level in wheat seedlings.
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Affiliation(s)
- Ruslan Yuldashev
- Institute of Biochemistry and Genetics, Ufa Scientific Centre, Russian Academy of Sciences, Pr. Oktyabrya 71, Ufa 450054, Russia
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De Vleesschauwer D, Van Buyten E, Satoh K, Balidion J, Mauleon R, Choi IR, Vera-Cruz C, Kikuchi S, Höfte M. Brassinosteroids antagonize gibberellin- and salicylate-mediated root immunity in rice. PLANT PHYSIOLOGY 2012; 158:1833-46. [PMID: 22353574 PMCID: PMC3320189 DOI: 10.1104/pp.112.193672] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 02/15/2012] [Indexed: 05/18/2023]
Abstract
Brassinosteroids (BRs) are a unique class of plant steroid hormones that orchestrate myriad growth and developmental processes. Although BRs have long been known to protect plants from a suite of biotic and abiotic stresses, our understanding of the underlying molecular mechanisms is still rudimentary. Aiming to further decipher the molecular logic of BR-modulated immunity, we have examined the dynamics and impact of BRs during infection of rice (Oryza sativa) with the root oomycete Pythium graminicola. Challenging the prevailing view that BRs positively regulate plant innate immunity, we show that P. graminicola exploits BRs as virulence factors and hijacks the rice BR machinery to inflict disease. Moreover, we demonstrate that this immune-suppressive effect of BRs is due, at least in part, to negative cross talk with salicylic acid (SA) and gibberellic acid (GA) pathways. BR-mediated suppression of SA defenses occurred downstream of SA biosynthesis, but upstream of the master defense regulators NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 and OsWRKY45. In contrast, BR alleviated GA-directed immune responses by interfering at multiple levels with GA metabolism, resulting in indirect stabilization of the DELLA protein and central GA repressor SLENDER RICE1 (SLR1). Collectively, these data favor a model whereby P. graminicola coopts the plant BR pathway as a decoy to antagonize effectual SA- and GA-mediated defenses. Our results highlight the importance of BRs in modulating plant immunity and uncover pathogen-mediated manipulation of plant steroid homeostasis as a core virulence strategy.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Monica Höfte
- Laboratory of Phytopathology, Ghent University, B–9000 Ghent, Belgium (D.D.V., E.V.B., M.H.); Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences, Tsukuba 305–8602, Ibaraki, Japan (K.S., S.K.); Plant Breeding, Genetics, and Biotechnology Division (J.B., I.-R.C., C.V.-C.) and Crop Research Informatics Laboratory (R.M.), International Rice Research Institute, 1099 Metro Manila, Philippines
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Ahammed GJ, Yuan HL, Ogweno JO, Zhou YH, Xia XJ, Mao WH, Shi K, Yu JQ. Brassinosteroid alleviates phenanthrene and pyrene phytotoxicity by increasing detoxification activity and photosynthesis in tomato. CHEMOSPHERE 2012; 86:546-55. [PMID: 22119279 DOI: 10.1016/j.chemosphere.2011.10.038] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 10/07/2011] [Accepted: 10/20/2011] [Indexed: 05/02/2023]
Abstract
The present study was carried out to investigate the effects of exogenously applied 24-epibrassinolide (BR) on growth, gas exchange, chlorophyll fluorescence characteristics, lipid peroxidation and antioxidant systems of tomato seedlings grown under different levels (0, 10, 30, 100 and 300μM) of phenanthrene (PHE) and pyrene (PYR) in hydroponics. A concentration-dependent decrease in growth, photosynthetic pigment contents, net photosynthetic rate (Pn), stomatal conductance (Gs), maximal quantum yield of PSII (Fv/Fm), effective quantum yield of PSII (Φ(PSII)), photochemical quenching coefficient (qP) has been observed following PHE and PYR exposure. By contrast, non-photochemical quenching coefficient (NPQ) was increased. PHE was found to induce higher stress than PYR. However, foliar or root application of BR (50nM and 5nM, respectively) alleviated all those depressions with a sharp improvement in the activity of photosynthetic machinery. The activities of guaicol peroxidase (GPOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) as well as content of malondialdehyde (MDA) were increased in a dose-dependent manner under PHE or PYR treatments. Compared with control the highest increments of GPOD, CAT, APX, GR and MDA by PHE/PYR alone treatments were observed following 300μM concentration, which were 67%, 87%, 53%, 95% and 74% by PHE and 42%, 53%, 30%, 86% and 62% by PYR, respectively. In addition, both reduced glutathione (GSH) and oxidized glutathione (GSSG) were induced by PHE or PYR. Interestingly, BR application in either form further increased enzymatic and non enzymatic antioxidants in tomato roots treated with PHE or PYR. Our results suggest that BR has an anti-stress effect on tomato seedlings contaminated with PHE or PYR and this effect is mainly attributed by increased detoxification activity.
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Affiliation(s)
- Golam Jalal Ahammed
- Department of Horticulture, Zijingang Campus, Zhejiang University, Yu Hang Tang Road 866, Hangzhou 310058, PR China
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Balmer D, Mauch-Mani B. Plant Hormones and Metabolites as Universal Vocabulary in Plant Defense Signaling. BIOCOMMUNICATION OF PLANTS 2012. [DOI: 10.1007/978-3-642-23524-5_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Shakirova FM, Avalbaev AM, Bezrukova MV, Fatkhutdinova RA, Maslennikova DR, Yuldashev RA, Allagulova CR, Lastochkina OV. Hormonal Intermediates in the Protective Action of Exogenous Phytohormones in Wheat Plants Under Salinity. PHYTOHORMONES AND ABIOTIC STRESS TOLERANCE IN PLANTS 2012:185-228. [DOI: 10.1007/978-3-642-25829-9_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/23/2023]
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Cui F, Liu L, Zhao Q, Zhang Z, Li Q, Lin B, Wu Y, Tang S, Xie Q. Arabidopsis ubiquitin conjugase UBC32 is an ERAD component that functions in brassinosteroid-mediated salt stress tolerance. THE PLANT CELL 2012; 24:233-44. [PMID: 22214659 PMCID: PMC3289556 DOI: 10.1105/tpc.111.093062] [Citation(s) in RCA: 184] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Revised: 11/30/2011] [Accepted: 12/18/2011] [Indexed: 05/18/2023]
Abstract
Plants modify their growth and development to protect themselves from detrimental conditions by triggering a variety of signaling pathways, including the activation of the ubiquitin-mediated protein degradation pathway. Endoplasmic reticulum (ER)-associated protein degradation (ERAD) is an important aspect of the ubiquitin-proteasome system, but only a few of the active ERAD components have been reported in plants. Here, we report that the Arabidopsis thaliana ubiquitin-conjugating enzyme, UBC32, a stress-induced functional ubiquitin conjugation enzyme (E2) localized to the ER membrane, connects the ERAD process and brassinosteroid (BR)-mediated growth promotion and salt stress tolerance. In vivo data showed that UBC32 was a functional ERAD component that affected the stability of a known ERAD substrate, the barley (Hordeum vulgare) powdery mildew O (MLO) mutant MLO-12. UBC32 mutation caused the accumulation of bri1-5 and bri1-9, the mutant forms of the BR receptor, BRI1, and these mutant forms subsequently activated BR signal transduction. Further genetic and physiological data supported the contention that UBC32 plays a role in the BR-mediated salt stress response and that BR signaling is necessary for the plant to tolerate salt. Our data indicates a possible mechanism by which an ERAD component regulates the growth and stress response of plants.
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Affiliation(s)
- Feng Cui
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Lijing Liu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qingzhen Zhao
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- School of Life Science, Liaocheng University, Liaocheng 252059, China
| | - Zhonghui Zhang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qingliang Li
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Baoying Lin
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yaorong Wu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Sanyuan Tang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qi Xie
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- Address correspondence to
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Beste L, Nahar N, Dalman K, Fujioka S, Jonsson L, Dutta PC, Sitbon F. Synthesis of hydroxylated sterols in transgenic Arabidopsis plants alters growth and steroid metabolism. PLANT PHYSIOLOGY 2011; 157:426-440. [PMID: 21746809 PMCID: PMC3165889 DOI: 10.1104/pp.111.171199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 07/04/2011] [Indexed: 05/29/2023]
Abstract
To explore mechanisms in plant sterol homeostasis, we have here increased the turnover of sterols in Arabidopsis (Arabidopsis thaliana) and potato (Solanum tuberosum) plants by overexpressing four mouse cDNA encoding cholesterol hydroxylases (CHs), hydroxylating cholesterol at the C-7, C-24, C-25, or C-27 positions. Compared to the wild type, the four types of Arabidopsis transformant showed varying degrees of phenotypic alteration, the strongest one being in CH25 lines, which were dark-green dwarfs resembling brassinosteroid-related mutants. Gas chromatography-mass spectrometry analysis of extracts from wild-type Arabidopsis plants revealed trace levels of α and β forms of 7-hydroxycholesterol, 7-hydroxycampesterol, and 7-hydroxysitosterol. The expected hydroxycholesterol metabolites in CH7-, CH24-, and CH25 transformants were identified and quantified using gas chromatography-mass spectrometry. Additional hydroxysterol forms were also observed, particularly in CH25 plants. In CH24 and CH25 lines, but not in CH7 ones, the presence of hydroxysterols was correlated with a considerable alteration of the sterol profile and an increased sterol methyltransferase activity in microsomes. Moreover, CH25 lines contained clearly reduced levels of brassinosteroids, and displayed an enhanced drought tolerance. Equivalent transformations of potato plants with the CH25 construct increased hydroxysterol levels, but without the concomitant alteration of growth and sterol profiles observed in Arabidopsis. The results suggest that an increased hydroxylation of cholesterol and/or other sterols in Arabidopsis triggers compensatory processes, acting to maintain sterols at adequate levels.
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Beste L, Nahar N, Dalman K, Fujioka S, Jonsson L, Dutta PC, Sitbon F. Synthesis of hydroxylated sterols in transgenic Arabidopsis plants alters growth and steroid metabolism. PLANT PHYSIOLOGY 2011; 157:426-40. [PMID: 21746809 DOI: 10.1104/pp.110.171199] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
To explore mechanisms in plant sterol homeostasis, we have here increased the turnover of sterols in Arabidopsis (Arabidopsis thaliana) and potato (Solanum tuberosum) plants by overexpressing four mouse cDNA encoding cholesterol hydroxylases (CHs), hydroxylating cholesterol at the C-7, C-24, C-25, or C-27 positions. Compared to the wild type, the four types of Arabidopsis transformant showed varying degrees of phenotypic alteration, the strongest one being in CH25 lines, which were dark-green dwarfs resembling brassinosteroid-related mutants. Gas chromatography-mass spectrometry analysis of extracts from wild-type Arabidopsis plants revealed trace levels of α and β forms of 7-hydroxycholesterol, 7-hydroxycampesterol, and 7-hydroxysitosterol. The expected hydroxycholesterol metabolites in CH7-, CH24-, and CH25 transformants were identified and quantified using gas chromatography-mass spectrometry. Additional hydroxysterol forms were also observed, particularly in CH25 plants. In CH24 and CH25 lines, but not in CH7 ones, the presence of hydroxysterols was correlated with a considerable alteration of the sterol profile and an increased sterol methyltransferase activity in microsomes. Moreover, CH25 lines contained clearly reduced levels of brassinosteroids, and displayed an enhanced drought tolerance. Equivalent transformations of potato plants with the CH25 construct increased hydroxysterol levels, but without the concomitant alteration of growth and sterol profiles observed in Arabidopsis. The results suggest that an increased hydroxylation of cholesterol and/or other sterols in Arabidopsis triggers compensatory processes, acting to maintain sterols at adequate levels.
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Affiliation(s)
- Lisa Beste
- Department of Plant Biology and Forest Genetics, Uppsala BioCenter, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden
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Yang CJ, Zhang C, Lu YN, Jin JQ, Wang XL. The mechanisms of brassinosteroids' action: from signal transduction to plant development. MOLECULAR PLANT 2011; 4:588-600. [PMID: 21471332 DOI: 10.1093/mp/ssr020] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Brassinosteroids play diverse roles in plant growth and development. Plants deficient in brassinosteroid (BR) biosynthesis or defective in signal transduction show many abnormal developmental phenotypes, indicating the importance of both BR biosynthesis and the signaling pathway in regulating these biological processes. Recently, using genetics, proteomics, genomics, cell biology, and many other approaches, more components involved in the BR signaling pathway were identified. Furthermore, the physiological, cellular, and molecular mechanisms by which BRs regulate various aspects of plant development, are being discovered. These include root development, anther and pollen development and formation, stem elongation, vasculature differentiation, and cellulose biosynthesis, suggesting that the biological functions of BRs are far beyond promoting cell elongation. This review will focus on the up-to-date progresses about regulatory mechanisms of the BR signaling pathway and the physiological and molecular mechanisms whereby BRs regulate plant growth and development.
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Affiliation(s)
- Cang-Jin Yang
- State Key Laboratory of Genetic Engineering and Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200433, People's Republic of China
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Abstract
Sterols are eukaryotic membrane components with crucial roles in diverse cellular processes. Elucidation of sterol function relies on development of tools for in situ sterol visualization. Here we describe protocols for in situ sterol localization in Arabidopsis thaliana root cells, using filipin as a specific probe for detection of fluorescent filipin-sterol complexes. Currently, filipin is the only established tool for sterol visualization in plants. Filipin labeling can be performed on aldehyde-fixed samples, largely preserving fluorescent proteins and being compatible with immunocytochemistry. Filipin can also be applied for probing live cells, taking into account the fact that it inhibits sterol-dependent endocytosis. The experimental procedures described are designed for fluorescence detection by confocal laser-scanning microscopy with excitation of filipin-sterol complexes at 364 nm. The protocols require 1 d for sterol covisualization with fluorescent proteins in fixed or live roots and 2 d for immunocytochemistry on whole-mount roots.
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