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Prince SJ, Valliyodan B, Ye H, Yang M, Tai S, Hu W, Murphy M, Durnell LA, Song L, Joshi T, Liu Y, Van de Velde J, Vandepoele K, Grover Shannon J, Nguyen HT. Understanding genetic control of root system architecture in soybean: Insights into the genetic basis of lateral root number. PLANT, CELL & ENVIRONMENT 2019; 42:212-229. [PMID: 29749073 DOI: 10.1111/pce.13333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 03/26/2018] [Indexed: 05/04/2023]
Abstract
Developing crops with better root systems is a promising strategy to ensure productivity in both optimum and stress environments. Root system architectural traits in 397 soybean accessions were characterized and a high-density single nucleotide polymorphisms (SNPs)-based genome-wide association study was performed to identify the underlying genes associated with root structure. SNPs associated with root architectural traits specific to landraces and elite germplasm pools were detected. Four loci were detected in landraces for lateral root number (LRN) and distribution of root thickness in diameter Class I with a major locus on chromosome 16. This major loci was detected in the coding region of unknown protein, and subsequent analyses demonstrated that root traits are affected with mutated haplotypes of the gene. In elite germplasm pool, 3 significant SNPs in alanine-glyoxalate aminotransferase, Leucine-Rich Repeat receptor/No apical meristem, and unknown functional genes were found to govern multiple traits including root surface area and volume. However, no major loci were detected for LRN in elite germplasm. Nucleotide diversity analysis found evidence of selective sweeps around the landraces LRN gene. Soybean accessions with minor and mutated allelic variants of LRN gene were found to perform better in both water-limited and optimal field conditions.
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Affiliation(s)
- Silvas J Prince
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
- Noble Research Institute, Ardmore, 73401, OK, USA
| | - Babu Valliyodan
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
| | - Heng Ye
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
| | - Ming Yang
- BGI Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | | | - Wushu Hu
- BGI Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Mackensie Murphy
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
| | - Lorellin A Durnell
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
| | - Li Song
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
- Institutes of Agricultural Science and Technology Development, Joint International Research Laboratory of Agriculture and Agri-Product Safety, Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou, 225009, China
| | - Trupti Joshi
- Department of Computer Science, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
- Department of Molecular Microbiology and Immunology and Office of Research, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Yang Liu
- Department of Computer Science, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Jan Van de Velde
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 927, 9052, Ghent, Belgium
| | - Klaas Vandepoele
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, B-9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 927, 9052, Ghent, Belgium
| | - J Grover Shannon
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
| | - Henry T Nguyen
- Division of Plant Sciences, University of Missouri, Columbia, 65211, MO, USA
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Marsollier AC, Ingram G. Getting physical: invasive growth events during plant development. CURRENT OPINION IN PLANT BIOLOGY 2018; 46:8-17. [PMID: 29981931 DOI: 10.1016/j.pbi.2018.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 06/04/2018] [Accepted: 06/07/2018] [Indexed: 05/10/2023]
Abstract
Plant cells are enclosed in cell walls that weld them together, meaning that cells rarely change neighbours. Nonetheless, invasive growth events play critical roles in plant development and are often key hubs for the integration of environmental and/or developmental signalling. Here we review cellular processes involved in three such events: lateral root emergence, pollen tube growth through stigma and style tissues, and embryo expansion through the endosperm (Figures 1-3). We consider processes such as regulation of water fluxes and cell turgor (driving growth), cell wall modifications (e.g. cell separation) and cell death (for creating space) within these three contexts with the aim of identifying key mechanisms implicated in providing a chemical and biophysical environments permitting invasive growth events.
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Affiliation(s)
- Anne-Charlotte Marsollier
- Université de Lyon, Laboratoire Reproduction et Développement des Plantes, ENS de lyon, CNRS, INRA, 46 Allée d'Italie, 69007 Lyon, France
| | - Gwyneth Ingram
- Université de Lyon, Laboratoire Reproduction et Développement des Plantes, ENS de lyon, CNRS, INRA, 46 Allée d'Italie, 69007 Lyon, France.
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McGivern TJP, Slator C, Kellett A, Marmion CJ. Innovative DNA-Targeted Metallo-prodrug Strategy Combining Histone Deacetylase Inhibition with Oxidative Stress. Mol Pharm 2018; 15:5058-5071. [PMID: 30192548 DOI: 10.1021/acs.molpharmaceut.8b00652] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cancer remains a global health challenge. There is an urgent need to develop innovative therapeutics that can overcome the shortcomings of existing cancer therapies. DNA enzymes involved in nucleic acid compaction and organization are an attractive cancer drug target for therapeutic exploitation. In this work, a family of Cu(II) prodrugs containing suberoylanilide hydroxamic acid (SAHA), a well-established histone deacetylase inhibitor (HDACi) and clinically approved cancer drug, and phenanthrene ligands as DNA intercalative components have been rationally developed. The complexes, of general formula [Cu(SAHA-1H)( N, N'-phenanthrene)]+, exhibit excellent DNA recognition with binding affinity of lead agents in the order of ∼107 M(bp)-1. Biophysical studies involving nucleic acid polymers indicate intercalative binding at both adenine-thymine (A-T) and guanine-cytosine (G-C) rich sequences but thermodynamically stable interactions are favored in G-C tracts. The complexes mediate DNA damage by producing reactive oxygen species (ROS) with spin trapping experiments showing that superoxide, the hydroxyl radical, and hydrogen peroxide play critical roles in strand scission. The agents were found to have promising antiproliferative effects against a panel of epithelial cancers, and in two representative cell lines possessing mutated p53 (SK-OV-3 and DU145), enhanced cytotoxicity was observed. Significantly, mechanistic experiments with the most promising candidates revealed HDAC inhibition activity was achieved over a shorter time frame as compared to clinical standards with DNA damage-response markers identifying upregulation of both DNA synthesis and nucleotide excision repair (NER) pathways. Finally, confocal imaging and gene expression analysis show this metallodrug class exerts cytotoxic activity predominantly through an apoptotic pathway.
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Affiliation(s)
- Tadhg J P McGivern
- Centre for Synthesis and Chemical Biology, Department of Chemistry , Royal College of Surgeons in Ireland , 123 St. Stephen's Green , Dublin 2 , Ireland.,School of Chemical Sciences and National Institute for Cellular Biotechnology , Dublin City University , Glasnevin, Dublin 9 , Ireland
| | - Creina Slator
- School of Chemical Sciences and National Institute for Cellular Biotechnology , Dublin City University , Glasnevin, Dublin 9 , Ireland
| | - Andrew Kellett
- School of Chemical Sciences and National Institute for Cellular Biotechnology , Dublin City University , Glasnevin, Dublin 9 , Ireland
| | - Celine J Marmion
- Centre for Synthesis and Chemical Biology, Department of Chemistry , Royal College of Surgeons in Ireland , 123 St. Stephen's Green , Dublin 2 , Ireland
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Proteomic Analysis of Rapeseed Root Response to Waterlogging Stress. PLANTS 2018; 7:plants7030071. [PMID: 30205432 PMCID: PMC6160990 DOI: 10.3390/plants7030071] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 08/29/2018] [Accepted: 08/30/2018] [Indexed: 01/03/2023]
Abstract
The overall health of a plant is constantly affected by the changing and hostile environment. Due to climate change and the farming pattern of rice (Oryza sativa) and rapeseed (Brassica napus L.), stress from waterlogging poses a serious threat to productivity assurance and the yield of rapeseed in China's Yangtze River basin. In order to improve our understanding of the complex mechanisms behind waterlogging stress and identify waterlogging-responsive proteins, we firstly conducted iTRAQ (isobaric tags for relative and absolute quantification)-based quantitative proteomic analysis of rapeseed roots under waterlogging treatments, for both a tolerant cultivar ZS9 and sensitive cultivar GH01. A total of 7736 proteins were identified by iTRAQ, of which several hundred showed different expression levels, including 233, 365, and 326 after waterlogging stress for 4H, 8H, and 12H in ZS9, respectively, and 143, 175, and 374 after waterlogging stress for 4H, 8H, and 12H in GH01, respectively. For proteins repeatedly identified at different time points, gene ontology (GO) cluster analysis suggested that the responsive proteins of the two cultivars were both enriched in the biological process of DNA-dependent transcription and the oxidation⁻reduction process, and response to various stress and hormone stimulus, while different distribution frequencies in the two cultivars was investigated. Moreover, overlap proteins with similar or opposite tendencies of fold change between ZS9 and GH01 were observed and clustered based on the different expression ratios, suggesting the two genotype cultivars exhibited diversiform molecular mechanisms or regulation pathways in their waterlogging stress response. The following qRT-PCR (quantitative real-time polymerase chain reaction) results verified the candidate proteins at transcription levels, which were prepared for further research. In conclusion, proteins detected in this study might perform different functions in waterlogging responses and would provide information conducive to better understanding adaptive mechanisms under environmental stresses.
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Abstract
A major problem of climate change is the increasing duration and frequency of heavy rainfall events. This leads to soil flooding that negatively affects plant growth, eventually leading to death of plants if the flooding persists for several days. Most crop plants are very sensitive to flooding, and dramatic yield losses occur due to flooding each year. This review summarizes recent progress and approaches to enhance crop resistance to flooding. Most experiments have been done on maize, barley, and soybean. Work on other crops such as wheat and rape has only started. The most promising traits that might enhance crop flooding tolerance are anatomical adaptations such as aerenchyma formation, the formation of a barrier against radial oxygen loss, and the growth of adventitious roots. Metabolic adaptations might be able to improve waterlogging tolerance as well, but more studies are needed in this direction. Reasonable approaches for future studies are quantitative trait locus (QTL) analyses or genome-wide association (GWA) studies in combination with specific tolerance traits that can be easily assessed. The usage of flooding-tolerant relatives or ancestral cultivars of the crop of interest in these experiments might enhance the chances of finding useful tolerance traits to be used in breeding.
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Nguyen TN, Tuan PA, Mukherjee S, Son S, Ayele BT. Hormonal regulation in adventitious roots and during their emergence under waterlogged conditions in wheat. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:4065-4082. [PMID: 29788353 PMCID: PMC6054230 DOI: 10.1093/jxb/ery190] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 05/14/2018] [Indexed: 05/21/2023]
Abstract
To gain insights into the molecular mechanisms underlying hormonal regulation in adventitious roots and during their emergence under waterlogged conditions in wheat, the present study investigated transcriptional regulation of genes related to hormone metabolism and transport in the root and stem node tissues. Waterlogging-induced inhibition of axile root elongation and lateral root formation, and promotion of surface adventitious and axile root emergence and aerenchyma formation are associated with enhanced expression levels of ethylene biosynthesis genes, ACS7 and ACO2, in both tissues. Inhibition of axile root elongation is also related to increased root indole acetic acid (IAA) and jasmonate (JA) levels that are associated with up-regulation of specific IAA biosynthesis/transport (TDC, YUC1, and PIN9) and JA metabolism (LOX8, AOS1, AOC1, and JAR1) genes, and transcriptional alteration of gibberellin (GA) metabolism genes (GA3ox2 and GA2ox8). Adventitious root emergence from waterlogged stem nodes is associated with increased levels of IAA and GA but decreased levels of cytokinin and abscisic acid (ABA), which are regulated through the expression of specific IAA biosynthesis/transport (TDC, YUC1, and PIN9), cytokinin metabolism (IPT5-2, LOG1, CKX5, and ZOG2), ABA biosynthesis (NCED1 and NCED2), and GA metabolism (GA3ox2 and GA2ox8) genes. These results enhance our understanding of the molecular mechanisms underlying the adaptive response of wheat to waterlogging.
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Affiliation(s)
- Tran-Nguyen Nguyen
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Pham Anh Tuan
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Shalini Mukherjee
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - SeungHyun Son
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Belay T Ayele
- Department of Plant Science, University of Manitoba, Winnipeg, Manitoba, Canada
- Correspondence:
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57
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Lei C, Fan S, Li K, Meng Y, Mao J, Han M, Zhao C, Bao L, Zhang D. iTRAQ-Based Proteomic Analysis Reveals Potential Regulation Networks of IBA-Induced Adventitious Root Formation in Apple. Int J Mol Sci 2018; 19:ijms19030667. [PMID: 29495482 PMCID: PMC5877528 DOI: 10.3390/ijms19030667] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 02/14/2018] [Accepted: 02/22/2018] [Indexed: 01/19/2023] Open
Abstract
Adventitious root (AR) formation, which is controlled by endogenous and environmental factors, is indispensable for vegetative asexual propagation. However, comprehensive proteomic data on AR formation are still lacking. The aim of this work was to study indole-3-butyric acid (IBA)-induced AR formation in the dwarf apple rootstock 'T337'. In this study, the effect of IBA on AR formation was analysed. Subsequent to treatment with IBA, both the rooting rate and root length of 'T337' increased significantly. An assessment of hormone levels in basal stem cuttings suggested that auxin, abscisic acid, and brassinolide were higher in basal stem cuttings that received the exogenous IBA application; while zeatin riboside, gibberellins, and jasmonic acid were lower than non-treated basal stem cuttings. To explore the underlying molecular mechanism, an isobaric tags for relative and absolute quantification (iTRAQ)-based proteomic technique was employed to identify the expression profiles of proteins at a key period of adventitious root induction (three days after IBA treatment). In total, 3355 differentially expressed proteins (DEPs) were identified. Many DEPs were closely related to carbohydrate metabolism and energy production, protein homeostasis, reactive oxygen and nitric oxide signaling, and cell wall remodeling biological processes; as well as the phytohormone signaling, which was the most critical process in response to IBA treatment. Further, RT-qPCR analysis was used to evaluate the expression level of nine genes that are involved in phytohormone signaling and their transcriptional levels were mostly in accordance with the protein patterns. Finally, a putative work model was proposed. Our study establishes a foundation for further research and sheds light on IBA-mediated AR formation in apple as well as other fruit rootstock cuttings.
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Affiliation(s)
- Chao Lei
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Sheng Fan
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Ke Li
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Yuan Meng
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Jiangping Mao
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Mingyu Han
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Caiping Zhao
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Lu Bao
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
| | - Dong Zhang
- College of Horticulture, Northwest A&F University, Yangling 712100, China.
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Yamauchi T, Colmer TD, Pedersen O, Nakazono M. Regulation of Root Traits for Internal Aeration and Tolerance to Soil Waterlogging-Flooding Stress. PLANT PHYSIOLOGY 2018; 176:1118-1130. [PMID: 29118247 PMCID: PMC5812745 DOI: 10.1104/pp.17.01157] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/03/2017] [Indexed: 05/15/2023]
Affiliation(s)
- Takaki Yamauchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
| | - Timothy D Colmer
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Ole Pedersen
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, Crawley, Western Australia 6009, Australia
- Freshwater Biological Laboratory, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Mikio Nakazono
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, Crawley, Western Australia 6009, Australia
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Sasidharan R, Hartman S, Liu Z, Martopawiro S, Sajeev N, van Veen H, Yeung E, Voesenek LACJ. Signal Dynamics and Interactions during Flooding Stress. PLANT PHYSIOLOGY 2018; 176:1106-1117. [PMID: 29097391 PMCID: PMC5813540 DOI: 10.1104/pp.17.01232] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/27/2017] [Indexed: 05/20/2023]
Abstract
Flooding is detrimental for nearly all higher plants, including crops. The compound stress elicited by slow gas exchange and low light levels under water is responsible for both a carbon and an energy crisis ultimately leading to plant death. The endogenous concentrations of four gaseous compounds, oxygen, carbon dioxide, ethylene, and nitric oxide, change during the submergence of plant organs in water. These gases play a pivotal role in signal transduction cascades, leading to adaptive processes such as metabolic adjustments and anatomical features. Of these gases, ethylene is seen as the most consistent, pervasive, and reliable signal of early flooding stress, most likely in tight interaction with the other gases. The production of reactive oxygen species (ROS) in plant cells during flooding and directly after subsidence, during which the plant is confronted with high light and oxygen levels, is characteristic for this abiotic stress. Low, well-controlled levels of ROS are essential for adaptive signaling pathways, in interaction with the other gaseous flooding signals. On the other hand, excessive uncontrolled bursts of ROS can be highly damaging for plants. Therefore, a fine-tuned balance is important, with a major role for ROS production and scavenging. Our understanding of the temporal dynamics of the four gases and ROS is basal, whereas it is likely that they form a signature readout of prevailing flooding conditions and subsequent adaptive responses.
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Affiliation(s)
- Rashmi Sasidharan
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Sjon Hartman
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Zeguang Liu
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Shanice Martopawiro
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Nikita Sajeev
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
- Molecular Plant Physiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Hans van Veen
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Elaine Yeung
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Laurentius A C J Voesenek
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584 CH Utrecht, The Netherlands
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Phukan UJ, Jeena GS, Tripathi V, Shukla RK. MaRAP2-4, a waterlogging-responsive ERF from Mentha, regulates bidirectional sugar transporter AtSWEET10 to modulate stress response in Arabidopsis. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:221-233. [PMID: 28636266 PMCID: PMC5785340 DOI: 10.1111/pbi.12762] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 04/28/2017] [Accepted: 05/19/2017] [Indexed: 05/20/2023]
Abstract
As waterlogging and successive events severely influence growth and development of economically important plants, we attempted to characterize the role of a waterlogging-responsive group I (A-6) ethylene response factor (MaRAP2-4) from Mentha arvensis. Waterlogging, ethylene and methyl jasmonate rapidly induced the expression of MaRAP2-4. MaRAP2-4 interacted with multiple cis-elements like dehydration response elements (DRE1/2), anoxia/jasmonic acid response element (JARE) and GCC box showing its involvement in multiple responses. MaRAP2-4 localizes in the nucleus and acts as a transcriptional activator. Truncation and internal deletion identified a 20 amino acids potential transactivation domain (PLPSSVDAKLEAICQSLAIN) in MaRAP2-4. MaRAP2-4 transgenic Arabidopsis showed enhanced waterlogging and subsequent oxidative stress tolerance. Microarray analysis revealed that within up-regulated genes 483, 212 and 132 promoters carry either single or multiple copies of DRE, JARE and GCC cis-element/s, respectively. Within these promoters, a large section belongs to carbohydrate metabolism/transport, including many SWEET transporters. Further analysis showed MaRAP2-4 specifically targets two positions in AtSWEEET10 promoter carrying DRE and/or GCC box that might regulate carbohydrate availability and waterlogging tolerance. These results demonstrate that MaRAP2-4 is a positive regulator of waterlogging tolerance, and as energy-consuming processes such as carbohydrate biosynthesis are reduced under waterlogging-induced hypoxia, sugar transport through SWEETs may be the primary option to make sugar available to the required tissue.
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Affiliation(s)
- Ujjal J. Phukan
- Biotechnology DivisionCSIR‐Central Institute of Medicinal and Aromatic Plants (CSIR‐CIMAP)LucknowIndia
| | - Gajendra Singh Jeena
- Biotechnology DivisionCSIR‐Central Institute of Medicinal and Aromatic Plants (CSIR‐CIMAP)LucknowIndia
| | | | - Rakesh Kumar Shukla
- Biotechnology DivisionCSIR‐Central Institute of Medicinal and Aromatic Plants (CSIR‐CIMAP)LucknowIndia
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Zhang Q, Huber H, Beljaars SJM, Birnbaum D, de Best S, de Kroon H, Visser EJW. Benefits of flooding-induced aquatic adventitious roots depend on the duration of submergence: linking plant performance to root functioning. ANNALS OF BOTANY 2017; 120:171-180. [PMID: 28586427 PMCID: PMC5737540 DOI: 10.1093/aob/mcx049] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 05/12/2017] [Indexed: 05/17/2023]
Abstract
Background and Aims Temporal flooding is a common environmental stress for terrestrial plants. Aquatic adventitious roots (aquatic roots) are commonly formed in flooding-tolerant plant species and are generally assumed to be beneficial for plant growth by supporting water and nutrient uptake during partial flooding. However, the actual contribution of these roots to plant performance under flooding has hardly been quantified. As the investment into aquatic root development in terms of carbohydrates may be costly, these costs may - depending on the specific environmental conditions - offset the beneficial effects of aquatic roots. This study tested the hypothesis that the balance between potential costs and benefits depends on the duration of flooding, as the benefits are expected to outweigh the costs in long-term but not in short-term flooding. Methods The contribution of aquatic roots to plant performance was tested in Solanum dulcamara during 1-4 weeks of partial submergence and by experimentally manipulating root production. Nutrient uptake by aquatic roots, transpiration and photosynthesis were measured in plants differing in aquatic root development to assess the specific function of these roots. Key Results As predicted, flooded plants benefited from the presence of aquatic roots. The results showed that this was probably due to the contribution of roots to resource uptake. However, these beneficial effects were only present in long-term but not in short-term flooding. This relationship could be explained by the correlation between nutrient uptake and the flooding duration-dependent size of the aquatic root system. Conclusions The results indicate that aquatic root formation is likely to be selected for in habitats characterized by long-term flooding. This study also revealed only limited costs associated with adventitious root formation, which may explain the maintenance of the ability to produce aquatic roots in habitats characterized by very rare or short flooding events.
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Affiliation(s)
- Qian Zhang
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
| | - Heidrun Huber
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
| | - Simone J. M. Beljaars
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
| | - Diana Birnbaum
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
| | - Sander de Best
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
| | - Hans de Kroon
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
| | - Eric J. W. Visser
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands
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Pucciariello C, Perata P. New insights into reactive oxygen species and nitric oxide signalling under low oxygen in plants. PLANT, CELL & ENVIRONMENT 2017; 40:473-482. [PMID: 26799776 DOI: 10.1111/pce.12715] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 12/30/2015] [Accepted: 01/13/2016] [Indexed: 05/10/2023]
Abstract
Plants produce reactive oxygen species (ROS) when exposed to low oxygen (O2 ). Much experimental evidence has demonstrated the existence of an oxidative burst when there is an O2 shortage. This originates at various subcellular sites. The activation of NADPH oxidase(s), in complex with other proteins, is responsible for ROS production at the plasma membrane. Another source of low O2 -dependent ROS is the mitochondrial electron transport chain, which misfunctions when low O2 limits its activity. Arabidopsis mutants impaired in proteins playing a role in ROS production display an intolerant phenotype to anoxia and submergence, suggesting a role in acclimation to stress. In rice, the presence of the submergence 1A (SUB1A) gene for submergence tolerance is associated with a higher capacity to scavenge ROS. Additionally, the destabilization of group VII ethylene responsive factors, which are involved in the direct O2 sensing mechanism, requires nitric oxide (NO). All this evidence suggests the existence of a ROS and NO - low O2 mechanism interplay which likely includes sensing, anaerobic metabolism and acclimation to stress. In this review, we summarize the most recent findings on this topic, formulating hypotheses on the basis of the latest advances.
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Akman M, Kleine R, van Tienderen PH, Schranz EM. Identification of the Submergence Tolerance QTL Come Quick Drowning1 (CQD1) in Arabidopsis thaliana. J Hered 2017; 108:308-317. [DOI: 10.1093/jhered/esx014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 02/12/2017] [Indexed: 01/03/2023] Open
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Ortega-Villasante C, Burén S, Barón-Sola Á, Martínez F, Hernández LE. In vivo ROS and redox potential fluorescent detection in plants: Present approaches and future perspectives. Methods 2016; 109:92-104. [DOI: 10.1016/j.ymeth.2016.07.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 07/08/2016] [Accepted: 07/11/2016] [Indexed: 11/16/2022] Open
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65
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Zhu C, Yang N, Guo Z, Qian M, Gan L. An ethylene and ROS-dependent pathway is involved in low ammonium-induced root hair elongation in Arabidopsis seedlings. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 105:37-44. [PMID: 27074220 DOI: 10.1016/j.plaphy.2016.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/29/2016] [Accepted: 04/01/2016] [Indexed: 05/08/2023]
Abstract
Root hairs are plastic in response to nutrient supply, but relatively little is known about their development under low ammonium (NH4(+)) conditions. This study showed that reducing NH4(+) for 3 days in wild-type Arabidopsis seedlings resulted in drastic elongation of root hairs. To investigate the possible mediation of ethylene and auxin in this process, seedlings were treated with 2,3,5-triiodobenzoic acid (TIBA, auxin transport inhibitor), 1-naphthylphthalamic acid (NPA, auxin transport inhibitor), p-chlorophenoxy isobutyric acid (PCIB, auxin action inhibitor), aminoethoxyvinylglycine (AVG, chemical inhibitor of ethylene biosynthesis), or silver ions (Ag(+), ethylene perception antagonist) under low NH4(+) conditions. Our results showed that TIBA, NPA and PCIB did not inhibit root hair elongation under low NH4(+) conditions, while AVG and Ag(+) completely inhibited low NH4(+)-induced root hair elongation. This suggested that low NH4(+)-induced root hair elongation was dependent on the ethylene pathway, but not the auxin pathway. Further genetic studies revealed that root hair elongation in auxin-insensitive mutants was sensitive to low NH4(+) treatment, but elongation was less sensitive in ethylene-insensitive mutants than wild-type plants. In addition, low NH4(+)-induced root hair elongation was accompanied by reactive oxygen species (ROS) accumulation. Diphenylene iodonium (DPI, NADPH oxidase inhibitor) and dimethylthiourea (DMTU, ROS scavenger) inhibited low NH4(+)-induced root hair elongation, suggesting that ROS were involved in this process. Moreover, ethylene acted together with ROS to modulate root hair elongation under low NH4(+) conditions. These results demonstrate that a signaling pathway involving ethylene and ROS participates in regulation of root hair elongation when Arabidopsis seedlings are subjected to low NH4(+) conditions.
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Affiliation(s)
- Changhua Zhu
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Na Yang
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhengfei Guo
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Meng Qian
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lijun Gan
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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66
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Farnese FS, Menezes-Silva PE, Gusman GS, Oliveira JA. When Bad Guys Become Good Ones: The Key Role of Reactive Oxygen Species and Nitric Oxide in the Plant Responses to Abiotic Stress. FRONTIERS IN PLANT SCIENCE 2016; 7:471. [PMID: 27148300 PMCID: PMC4828662 DOI: 10.3389/fpls.2016.00471] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 03/24/2016] [Indexed: 05/18/2023]
Abstract
The natural environment of plants is composed of a complex set of abiotic stresses and their ability to respond to these stresses is highly flexible and finely balanced through the interaction between signaling molecules. In this review, we highlight the integrated action between reactive oxygen species (ROS) and reactive nitrogen species (RNS), particularly nitric oxide (NO), involved in the acclimation to different abiotic stresses. Under stressful conditions, the biosynthesis transport and the metabolism of ROS and NO influence plant response mechanisms. The enzymes involved in ROS and NO synthesis and scavenging can be found in different cells compartments and their temporal and spatial locations are determinant for signaling mechanisms. Both ROS and NO are involved in long distances signaling (ROS wave and GSNO transport), promoting an acquired systemic acclimation to abiotic stresses. The mechanisms of abiotic stresses response triggered by ROS and NO involve some general steps, as the enhancement of antioxidant systems, but also stress-specific mechanisms, according to the stress type (drought, hypoxia, heavy metals, etc.), and demand the interaction with other signaling molecules, such as MAPK, plant hormones, and calcium. The transduction of ROS and NO bioactivity involves post-translational modifications of proteins, particularly S-glutathionylation for ROS, and S-nitrosylation for NO. These changes may alter the activity, stability, and interaction with other molecules or subcellular location of proteins, changing the entire cell dynamics and contributing to the maintenance of homeostasis. However, despite the recent advances about the roles of ROS and NO in signaling cascades, many challenges remain, and future studies focusing on the signaling of these molecules in planta are still necessary.
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Affiliation(s)
- Fernanda S. Farnese
- Laboratory of Plant Ecophysiology, Instituto Federal Goiano – Campus Rio VerdeGoiás, Brazil
| | - Paulo E. Menezes-Silva
- Laboratory of Plant Ecophysiology, Instituto Federal Goiano – Campus Rio VerdeGoiás, Brazil
| | - Grasielle S. Gusman
- Laboratory of Plant Chemistry, Univiçosa – Faculdade de Ciências Biológicas e da SaúdeViçosa, Brazil
| | - Juraci A. Oliveira
- Department of General Biology, Universidade Federal de ViçosaViçosa, Brazil
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67
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Steffens B, Rasmussen A. The Physiology of Adventitious Roots. PLANT PHYSIOLOGY 2016; 170:603-17. [PMID: 26697895 PMCID: PMC4734560 DOI: 10.1104/pp.15.01360] [Citation(s) in RCA: 232] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/27/2015] [Indexed: 05/17/2023]
Abstract
Adventitious roots are plant roots that form from any nonroot tissue and are produced both during normal development (crown roots on cereals and nodal roots on strawberry [Fragaria spp.]) and in response to stress conditions, such as flooding, nutrient deprivation, and wounding. They are important economically (for cuttings and food production), ecologically (environmental stress response), and for human existence (food production). To improve sustainable food production under environmentally extreme conditions, it is important to understand the adventitious root development of crops both in normal and stressed conditions. Therefore, understanding the regulation and physiology of adventitious root formation is critical for breeding programs. Recent work shows that different adventitious root types are regulated differently, and here, we propose clear definitions of these classes. We use three case studies to summarize the physiology of adventitious root development in response to flooding (case study 1), nutrient deficiency (case study 2), and wounding (case study 3).
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Affiliation(s)
- Bianka Steffens
- Plant Physiology, Philipps University, 35043 Marburg, Germany (B.S.); andDivision of Plant and Crop Science, University of Nottingham, Sutton Bonington LE12 5RD, United Kingdom (A.R.)
| | - Amanda Rasmussen
- Plant Physiology, Philipps University, 35043 Marburg, Germany (B.S.); andDivision of Plant and Crop Science, University of Nottingham, Sutton Bonington LE12 5RD, United Kingdom (A.R.)
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68
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Slator C, Barron N, Howe O, Kellett A. [Cu(o-phthalate)(phenanthroline)] Exhibits Unique Superoxide-Mediated NCI-60 Chemotherapeutic Action through Genomic DNA Damage and Mitochondrial Dysfunction. ACS Chem Biol 2016; 11:159-71. [PMID: 26488846 DOI: 10.1021/acschembio.5b00513] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The in cellulo catalytic production of reactive oxygen species (ROS) by copper(II) and iron(II) complexes is now recognized as a major mechanistic model in the design of effective cytotoxins of human cancer. The developmental complex, [Cu(o-phthalate)(1,10-phenanthroline)] (Cu-Ph), was recently reported as an intracellular ROS-active cytotoxic agent that induces double strand breaks in the genome of human cancer cells. In this work, we report the broad-spectrum action of Cu-Ph within the National Cancer Institute's (NCI) Developmental Therapeutics Program (DTP), 60 human cancer cell line screen. The activity profile is compared to established clinical agents-via the COMPARE algorithm-and reveals a novel mode of action to existing metal-based therapeutics. In this study, we identify the mechanistic activity of Cu-Ph through a series of molecular biological studies that are compared directly to the clinical DNA intercalator and topoisomerase II poison doxorubicin. The presence of ROS-specific scavengers was employed for in vitro and intracellular evaluation of prevailing radical species responsible for DNA oxidation with superoxide identified as playing a critical role in this mechanism. The ROS targeting properties of Cu-Ph on mitochondrial membrane potential were investigated, which showed that it had comparable activity to the uncoupling ionophore, carbonyl cyanide m-chlorophenyl hydrazine. The induction and origins of apoptotic activation were probed through detection of Annexin V and the activation of initiator (8,9) and executioner caspases (3/7) and were structurally visualized using confocal microscopy. Results here confirm a unique radical-induced mechanistic profile with intracellular hallmarks of damage to both genomic DNA and mitochondria.
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Affiliation(s)
- Creina Slator
- School
of Chemical Sciences and National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Niall Barron
- School
of Chemical Sciences and National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Orla Howe
- School of Biological Sciences & Focas Research Institute, Dublin Institute of Technology, Camden Row, Dublin 8, Ireland
| | - Andrew Kellett
- School
of Chemical Sciences and National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland
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69
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Voesenek LACJ, Sasidharan R, Visser EJW, Bailey-Serres J. Flooding stress signaling through perturbations in oxygen, ethylene, nitric oxide and light. THE NEW PHYTOLOGIST 2016; 209:39-43. [PMID: 26625347 DOI: 10.1111/nph.13775] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Affiliation(s)
- Laurentius A C J Voesenek
- Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
| | - Rashmi Sasidharan
- Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
| | - Eric J W Visser
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University, Nijmegen, the Netherlands
| | - Julia Bailey-Serres
- Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
- Center for Plant Cell Biology, Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
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70
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Sasidharan R, Voesenek LACJ. Ethylene-Mediated Acclimations to Flooding Stress. PLANT PHYSIOLOGY 2015; 169:3-12. [PMID: 25897003 PMCID: PMC4577390 DOI: 10.1104/pp.15.00387] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 04/18/2015] [Indexed: 05/18/2023]
Abstract
Flooding is detrimental for plants, primarily because of restricted gas exchange underwater, which leads to an energy and carbohydrate deficit. Impeded gas exchange also causes rapid accumulation of the volatile ethylene in all flooded plant cells. Although several internal changes in the plant can signal the flooded status, it is the pervasive and rapid accumulation of ethylene that makes it an early and reliable flooding signal. Not surprisingly, it is a major regulator of several flood-adaptive plant traits. Here, we discuss these major ethylene-mediated traits, their functional relevance, and the recent progress in identifying the molecular and signaling events underlying these traits downstream of ethylene. We also speculate on the role of ethylene in postsubmergence recovery and identify several questions for future investigations.
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Affiliation(s)
- Rashmi Sasidharan
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584-CH Utrecht, The Netherlands
| | - Laurentius A C J Voesenek
- Plant Ecophysiology, Institute of Environmental Biology, Utrecht University, 3584-CH Utrecht, The Netherlands
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71
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Phukan UJ, Mishra S, Shukla RK. Waterlogging and submergence stress: affects and acclimation. Crit Rev Biotechnol 2015; 36:956-66. [PMID: 26177332 DOI: 10.3109/07388551.2015.1064856] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Submergence, whether partial or complete, imparts some serious consequences on plants grown in flood prone ecosystems. Some plants can endure these conditions by embracing various survival strategies, including morphological adaptations and physiological adjustments. This review summarizes recent progress made in understanding of the stress and the acclimation responses of plants under waterlogged or submerged conditions. Waterlogging and submergence are often associated with hypoxia development, which may trigger various morphological traits and cellular acclimation responses. Ethylene, abscisic acid, gibberellic acid and other hormones play a crucial role in the survival process which is controlled genetically. Effects at the cellular level, including ATP management, starch metabolism, elemental toxicity, role of transporters and redox status have been explained. Transcriptional and hormonal interplay during this stress may provide some key aspects in understanding waterlogging and submergence tolerance. The level and degree of tolerance may vary depending on species or climatic variations which need to be studied for a proper understanding of waterlogging stress at the global level. The exploration of regulatory pathways and interplay in model organisms such as Arabidopsis and rice would provide valuable resources for improvement of economically and agriculturally important plants in waterlogging affected areas.
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Affiliation(s)
- Ujjal J Phukan
- a Biotechnology Division (CSIR-CIMAP) , Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP) , Lucknow , Uttar Pradesh , India
| | - Sonal Mishra
- a Biotechnology Division (CSIR-CIMAP) , Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP) , Lucknow , Uttar Pradesh , India
| | - Rakesh Kumar Shukla
- a Biotechnology Division (CSIR-CIMAP) , Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP) , Lucknow , Uttar Pradesh , India
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72
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Abu-Abied M, Rogovoy Stelmakh O, Mordehaev I, Grumberg M, Elbaum R, Wasteneys GO, Sadot E. Dissecting the contribution of microtubule behaviour in adventitious root induction. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:2813-24. [PMID: 25788735 PMCID: PMC4986881 DOI: 10.1093/jxb/erv097] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Induction of adventitious roots (ARs) in recalcitrant plants often culminates in cell division and callus formation rather than root differentiation. Evidence is provided here to suggest that microtubules (MTs) play a role in the shift from cell division to cell differentiation during AR induction. First, it was found that fewer ARs form in the temperature-sensitive mutant mor1-1, in which the MT-associated protein MOR1 is mutated, and in bot1-1, in which the MT-severing protein katanin is mutated. In the two latter mutants, MT dynamics and form are perturbed. By contrast, the number of ARs increased in RIC1-OX3 plants, in which MT bundling is enhanced and katanin is activated. In addition, any1 plants in which cell walls are perturbed made more ARs than wild-type plants. MT perturbations during AR induction in mor1-1 or in wild-type hypocotyls treated with oryzalin led to the formation of amorphous clusters of cells reminiscent of callus. In these cells a specific pattern of polarized light retardation by the cell walls was lost. PIN1 polarization and auxin maxima were hampered and differentiation of the epidermis was inhibited. It is concluded that a fine-tuned crosstalk between MTs, cell walls, and auxin transport is required for proper AR induction.
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Affiliation(s)
- Mohamad Abu-Abied
- The Institute of Plant Sciences, The Volcani Center, ARO, PO Box 6, Bet-Dagan 50250, Israel
| | | | - Inna Mordehaev
- The Institute of Plant Sciences, The Volcani Center, ARO, PO Box 6, Bet-Dagan 50250, Israel
| | - Marina Grumberg
- The Institute of Plant Sciences, The Volcani Center, ARO, PO Box 6, Bet-Dagan 50250, Israel
| | - Rivka Elbaum
- The Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Geoffrey O Wasteneys
- Department of Botany, The University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada
| | - Einat Sadot
- The Institute of Plant Sciences, The Volcani Center, ARO, PO Box 6, Bet-Dagan 50250, Israel
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73
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Molphy Z, Slator C, Chatgilialoglu C, Kellett A. DNA oxidation profiles of copper phenanthrene chemical nucleases. Front Chem 2015; 3:28. [PMID: 25954741 PMCID: PMC4404973 DOI: 10.3389/fchem.2015.00028] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/30/2015] [Indexed: 01/04/2023] Open
Abstract
The deleterious effects of metal-catalyzed reactive oxygen species (ROS) in biological systems can be seen in a wide variety of pathological conditions including cancer, cardiovascular disease, aging, and neurodegenerative disorder. On the other hand however, targeted ROS production in the vicinity of nucleic acids—as demonstrated by metal-activated bleomycin—has paved the way for ROS-active chemotherapeutic drug development. Herein we report mechanistic investigations into the oxidative nuclease activity and redox properties of copper(II) developmental therapeutics [Cu(DPQ)(phen)]2+ (Cu-DPQ-Phen), [Cu(DPPZ)(phen)]2+ (Cu-DPPZ-Phen), and [{Cu(phen)2}2(μ-terph)](terph) (Cu-Terph), with results being compared directly to Sigman's reagent [Cu(phen)2]2+ throughout (phen = 1,10-phenanthroline; DPQ = dipyridoquinoxaline; DPPZ = dipyridophenazine; Terph = terephthalate). Oxidative DNA damage was identified at the minor groove through use of surface bound recognition elements of methyl green, netropsin, and [Co(NH3)6]Cl3 that functioned to control complex accessibility at selected regions. ROS-specific scavengers and stabilizers were employed to identify the cleavage process, the results of which infer hydrogen peroxide produced metal-hydroxo or free hydroxyl radicals (•OH) as the predominant species. The extent of DNA damage owing to these radicals was then quantified through 8-oxo-2′-deoxyguanosine (8-oxo-dG) lesion detection under ELISA protocol with the overall trend following Cu-DPQ-Phen > Cu-Terph > Cu-Phen > Cu-DPPZ. Finally, the effects of oxidative damage on DNA replication processes were investigated using the polymerase chain reaction (PCR) where amplification of 120 base pair DNA sequences of varying base content were inhibited—particularly along A-T rich chains—through oxidative damage of template strands.
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Affiliation(s)
- Zara Molphy
- School of Chemical Sciences, National Institute for Cellular Biotechnology, Dublin City University Dublin, Ireland
| | - Creina Slator
- School of Chemical Sciences, National Institute for Cellular Biotechnology, Dublin City University Dublin, Ireland
| | - Chryssostomos Chatgilialoglu
- Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche Bologna, Italy ; Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos," Athens, Greece
| | - Andrew Kellett
- School of Chemical Sciences, National Institute for Cellular Biotechnology, Dublin City University Dublin, Ireland
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74
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Voesenek LACJ, Bailey-Serres J. Flood adaptive traits and processes: an overview. THE NEW PHYTOLOGIST 2015; 206:57-73. [PMID: 25580769 DOI: 10.1111/nph.13209] [Citation(s) in RCA: 334] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 10/30/2014] [Indexed: 05/18/2023]
Abstract
Unanticipated flooding challenges plant growth and fitness in natural and agricultural ecosystems. Here we describe mechanisms of developmental plasticity and metabolic modulation that underpin adaptive traits and acclimation responses to waterlogging of root systems and submergence of aerial tissues. This includes insights into processes that enhance ventilation of submerged organs. At the intersection between metabolism and growth, submergence survival strategies have evolved involving an ethylene-driven and gibberellin-enhanced module that regulates growth of submerged organs. Opposing regulation of this pathway is facilitated by a subgroup of ethylene-response transcription factors (ERFs), which include members that require low O₂ or low nitric oxide (NO) conditions for their stabilization. These transcription factors control genes encoding enzymes required for anaerobic metabolism as well as proteins that fine-tune their function in transcription and turnover. Other mechanisms that control metabolism and growth at seed, seedling and mature stages under flooding conditions are reviewed, as well as findings demonstrating that true endurance of submergence includes an ability to restore growth following the deluge. Finally, we highlight molecular insights obtained from natural variation of domesticated and wild species that occupy different hydrological niches, emphasizing the value of understanding natural flooding survival strategies in efforts to stabilize crop yields in flood-prone environments.
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Affiliation(s)
- Laurentius A C J Voesenek
- Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
| | - Julia Bailey-Serres
- Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
- Center for Plant Cell Biology, Department of Botany and Plant Sciences, University of California, Riverside, CA, 92521, USA
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75
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Yin CC, Ma B, Collinge DP, Pogson BJ, He SJ, Xiong Q, Duan KX, Chen H, Yang C, Lu X, Wang YQ, Zhang WK, Chu CC, Sun XH, Fang S, Chu JF, Lu TG, Chen SY, Zhang JS. Ethylene responses in rice roots and coleoptiles are differentially regulated by a carotenoid isomerase-mediated abscisic acid pathway. THE PLANT CELL 2015; 27:1061-81. [PMID: 25841037 PMCID: PMC4558702 DOI: 10.1105/tpc.15.00080] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/17/2015] [Indexed: 05/05/2023]
Abstract
Ethylene and abscisic acid (ABA) act synergistically or antagonistically to regulate plant growth and development. ABA is derived from the carotenoid biosynthesis pathway. Here, we analyzed the interplay among ethylene, carotenoid biogenesis, and ABA in rice (Oryza sativa) using the rice ethylene response mutant mhz5, which displays a reduced ethylene response in roots but an enhanced ethylene response in coleoptiles. We found that MHZ5 encodes a carotenoid isomerase and that the mutation in mhz5 blocks carotenoid biosynthesis, reduces ABA accumulation, and promotes ethylene production in etiolated seedlings. ABA can largely rescue the ethylene response of the mhz5 mutant. Ethylene induces MHZ5 expression, the production of neoxanthin, an ABA biosynthesis precursor, and ABA accumulation in roots. MHZ5 overexpression results in enhanced ethylene sensitivity in roots and reduced ethylene sensitivity in coleoptiles. Mutation or overexpression of MHZ5 also alters the expression of ethylene-responsive genes. Genetic studies revealed that the MHZ5-mediated ABA pathway acts downstream of ethylene signaling to inhibit root growth. The MHZ5-mediated ABA pathway likely acts upstream but negatively regulates ethylene signaling to control coleoptile growth. Our study reveals novel interactions among ethylene, carotenogenesis, and ABA and provides insight into improvements in agronomic traits and adaptive growth through the manipulation of these pathways in rice.
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Affiliation(s)
- Cui-Cui Yin
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Biao Ma
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Derek Phillip Collinge
- Australian Research Council Centre of Excellence in Plant Energy Biology, Research School of Biology, Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Barry James Pogson
- Australian Research Council Centre of Excellence in Plant Energy Biology, Research School of Biology, Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Si-Jie He
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qing Xiong
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai-Xuan Duan
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hui Chen
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chao Yang
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiang Lu
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yi-Qin Wang
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wan-Ke Zhang
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Cheng-Cai Chu
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiao-Hong Sun
- National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Shuang Fang
- National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jin-Fang Chu
- National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Tie-Gang Lu
- Biotechnology Research Institute/National Key Facility for Genetic Resources and Gene Improvement, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Shou-Yi Chen
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jin-Song Zhang
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
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76
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Petrov V, Hille J, Mueller-Roeber B, Gechev TS. ROS-mediated abiotic stress-induced programmed cell death in plants. FRONTIERS IN PLANT SCIENCE 2015; 6:69. [PMID: 25741354 PMCID: PMC4332301 DOI: 10.3389/fpls.2015.00069] [Citation(s) in RCA: 373] [Impact Index Per Article: 41.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/26/2015] [Indexed: 05/18/2023]
Abstract
During the course of their ontogenesis plants are continuously exposed to a large variety of abiotic stress factors which can damage tissues and jeopardize the survival of the organism unless properly countered. While animals can simply escape and thus evade stressors, plants as sessile organisms have developed complex strategies to withstand them. When the intensity of a detrimental factor is high, one of the defense programs employed by plants is the induction of programmed cell death (PCD). This is an active, genetically controlled process which is initiated to isolate and remove damaged tissues thereby ensuring the survival of the organism. The mechanism of PCD induction usually includes an increase in the levels of reactive oxygen species (ROS) which are utilized as mediators of the stress signal. Abiotic stress-induced PCD is not only a process of fundamental biological importance, but also of considerable interest to agricultural practice as it has the potential to significantly influence crop yield. Therefore, numerous scientific enterprises have focused on elucidating the mechanisms leading to and controlling PCD in response to adverse conditions in plants. This knowledge may help develop novel strategies to obtain more resilient crop varieties with improved tolerance and enhanced productivity. The aim of the present review is to summarize the recent advances in research on ROS-induced PCD related to abiotic stress and the role of the organelles in the process.
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Affiliation(s)
- Veselin Petrov
- Institute of Molecular Biology and Biotechnology, PlovdivBulgaria
| | - Jacques Hille
- Department of Pharmacy, Faculty of Mathematics and Natural Sciences, University of Groningen, GroningenNetherlands
| | - Bernd Mueller-Roeber
- Department of Molecular Biology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam-GolmGermany
| | - Tsanko S. Gechev
- Institute of Molecular Biology and Biotechnology, PlovdivBulgaria
- Department of Molecular Biology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam-GolmGermany
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77
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Van Hautegem T, Waters AJ, Goodrich J, Nowack MK. Only in dying, life: programmed cell death during plant development. TRENDS IN PLANT SCIENCE 2015; 20:102-13. [PMID: 25457111 DOI: 10.1016/j.tplants.2014.10.003] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 09/26/2014] [Accepted: 10/03/2014] [Indexed: 05/21/2023]
Abstract
Programmed cell death (PCD) is a fundamental process of life. During the evolution of multicellular organisms, the actively controlled demise of cells has been recruited to fulfil a multitude of functions in development, differentiation, tissue homeostasis, and immune systems. In this review we discuss some of the multiple cases of PCD that occur as integral parts of plant development in a remarkable variety of cell types, tissues, and organs. Although research in the last decade has discovered a number of PCD regulators, mediators, and executers, we are still only beginning to understand the mechanistic complexity that tightly controls preparation, initiation, and execution of PCD as a process that is indispensable for successful vegetative and reproductive development of plants.
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Affiliation(s)
- Tom Van Hautegem
- Department of Plant Systems Biology, VIB, and Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Ghent, Belgium
| | - Andrew J Waters
- Institute of Molecular Plant Sciences, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh EH9 3JH, UK
| | - Justin Goodrich
- Institute of Molecular Plant Sciences, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh EH9 3JH, UK
| | - Moritz K Nowack
- Department of Plant Systems Biology, VIB, and Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Ghent, Belgium.
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78
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Shabala S, Shabala L, Barcelo J, Poschenrieder C. Membrane transporters mediating root signalling and adaptive responses to oxygen deprivation and soil flooding. PLANT, CELL & ENVIRONMENT 2014; 37:2216-33. [PMID: 24689809 DOI: 10.1111/pce.12339] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 03/24/2014] [Accepted: 03/25/2014] [Indexed: 05/20/2023]
Abstract
This review provides a comprehensive assessment of a previously unexplored topic: elucidating the role that plasma- and organelle-based membrane transporters play in plant-adaptive responses to flooding. We show that energy availability and metabolic shifts under hypoxia and anoxia are critical in regulating membrane-transport activity. We illustrate the high tissue and time dependence of this regulation, reveal the molecular identity of transporters involved and discuss the modes of their regulation. We show that both reduced oxygen availability and accumulation of transition metals in flooded roots result in a reduction in the cytosolic K(+) pool, ultimately determining the cell's fate and transition to programmed cell death (PCD). This process can be strongly affected by hypoxia-induced changes in the amino acid pool profile and, specifically, ϒ-amino butyric acid (GABA) accumulation. It is suggested that GABA plays an important regulatory role, allowing plants to proceed with H2 O2 signalling to activate a cascade of genes that mediate plant adaptation to flooding while at the same time, preventing the cell from entering a 'suicide program'. We conclude that progress in crop breeding for flooding tolerance can only be achieved by pyramiding the numerous physiological traits that confer efficient energy maintenance, cytosolic ion homeostasis, and reactive oxygen species (ROS) control and detoxification.
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Affiliation(s)
- Sergey Shabala
- School of Land and Food, University of Tasmania, Hobart, TAS 7001, Australia
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79
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Maloney GS, DiNapoli KT, Muday GK. The anthocyanin reduced tomato mutant demonstrates the role of flavonols in tomato lateral root and root hair development. PLANT PHYSIOLOGY 2014; 166:614-31. [PMID: 25006027 PMCID: PMC4213093 DOI: 10.1104/pp.114.240507] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 07/03/2014] [Indexed: 05/20/2023]
Abstract
This study utilized tomato (Solanum lycopersicum) mutants with altered flavonoid biosynthesis to understand the impact of these metabolites on root development. The mutant anthocyanin reduced (are) has a mutation in the gene encoding FLAVONOID 3-HYDROXYLASE (F3H), the first step in flavonol synthesis, and accumulates higher concentrations of the F3H substrate, naringenin, and lower levels of the downstream products kaempferol, quercetin, myricetin, and anthocyanins, than the wild type. Complementation of are with the p35S:F3H transgene reduced naringenin and increased flavonols to wild-type levels. The initiation of lateral roots is reduced in are, and p35S:F3H complementation restores wild-type root formation. The flavonoid mutant anthocyanin without has a defect in the gene encoding DIHYDROFLAVONOL REDUCTASE, resulting in elevated flavonols and the absence of anthocyanins and displays increased lateral root formation. These results are consistent with a positive role of flavonols in lateral root formation. The are mutant has increased indole-3-acetic acid transport and greater sensitivity to the inhibitory effect of the auxin transport inhibitor naphthylphthalamic acid on lateral root formation. Expression of the auxin-induced reporter (DR5-β-glucuronidase) is reduced in initiating lateral roots and increased in primary root tips of are. Levels of reactive oxygen species are elevated in are root epidermal tissues and root hairs, and are forms more root hairs, consistent with a role of flavonols as antioxidants that modulate root hair formation. Together, these experiments identify positive roles of flavonols in the formation of lateral roots and negative roles in the formation of root hairs through the modulation of auxin transport and reactive oxygen species, respectively.
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Affiliation(s)
- Gregory S Maloney
- Department of Biology and Center for Molecular Communication and Signaling, Wake Forest University, Winston-Salem, North Carolina 27109
| | - Kathleen T DiNapoli
- Department of Biology and Center for Molecular Communication and Signaling, Wake Forest University, Winston-Salem, North Carolina 27109
| | - Gloria K Muday
- Department of Biology and Center for Molecular Communication and Signaling, Wake Forest University, Winston-Salem, North Carolina 27109
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80
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Tamang BG, Magliozzi JO, Maroof MAS, Fukao T. Physiological and transcriptomic characterization of submergence and reoxygenation responses in soybean seedlings. PLANT, CELL & ENVIRONMENT 2014; 37:2350-65. [PMID: 24433575 DOI: 10.1111/pce.12277] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/02/2014] [Accepted: 01/05/2014] [Indexed: 05/24/2023]
Abstract
Complete inundation at the early seedling stage is a common environmental constraint for soybean production throughout the world. As floodwaters subside, submerged seedlings are subsequently exposed to reoxygenation stress in the natural progression of a flood event. Here, we characterized the fundamental acclimation responses to submergence and reoxygenation in soybean at the seedling establishment stage. Approximately 90% of seedlings succumbed during 3 d of inundation under constant darkness, whereas 10 d of submergence were lethal to over 90% of seedlings under 12 h light/12 h dark cycles, indicating the significance of underwater photosynthesis in seedling survival. Submergence rapidly decreased the abundance of carbohydrate reserves and ATP in aerial tissue of seedlings although chlorophyll breakdown was not observed. The carbohydrate and ATP contents were recovered upon de-submergence, but sudden exposure to oxygen also induced lipid peroxidation, confirming that reoxygenation induced oxidative stress. Whole transcriptome analysis recognized genome-scale reconfiguration of gene expression that regulates various signalling and metabolic pathways under submergence and reoxygenation. Comparative analysis of differentially regulated genes in shoots and roots of soybean and other plants defines conserved, organ-specific and species-specific adjustments which enhance adaptability to submergence and reoxygenation through different metabolic pathways.
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Affiliation(s)
- Bishal G Tamang
- Department of Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg, VA, 24061, USA
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81
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Veley KM, Maksaev G, Frick EM, January E, Kloepper SC, Haswell ES. Arabidopsis MSL10 has a regulated cell death signaling activity that is separable from its mechanosensitive ion channel activity. THE PLANT CELL 2014; 26:3115-31. [PMID: 25052715 PMCID: PMC4145136 DOI: 10.1105/tpc.114.128082] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 06/19/2014] [Accepted: 06/27/2014] [Indexed: 05/08/2023]
Abstract
Members of the MscS superfamily of mechanosensitive ion channels function as osmotic safety valves, releasing osmolytes under increased membrane tension. MscS homologs exhibit diverse topology and domain structure, and it has been proposed that the more complex members of the family might have novel regulatory mechanisms or molecular functions. Here, we present a study of MscS-Like (MSL)10 from Arabidopsis thaliana that supports these ideas. High-level expression of MSL10-GFP in Arabidopsis induced small stature, hydrogen peroxide accumulation, ectopic cell death, and reactive oxygen species- and cell death-associated gene expression. Phosphomimetic mutations in the MSL10 N-terminal domain prevented these phenotypes. The phosphorylation state of MSL10 also regulated its ability to induce cell death when transiently expressed in Nicotiana benthamiana leaves but did not affect subcellular localization, assembly, or channel behavior. Finally, the N-terminal domain of MSL10 was sufficient to induce cell death in tobacco, independent of phosphorylation state. We conclude that the plant-specific N-terminal domain of MSL10 is capable of inducing cell death, this activity is regulated by phosphorylation, and MSL10 has two separable activities-one as an ion channel and one as an inducer of cell death. These findings further our understanding of the evolution and significance of mechanosensitive ion channels.
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Affiliation(s)
- Kira M Veley
- Department of Biology, Washington University, St. Louis, Missouri 63130
| | - Grigory Maksaev
- Department of Biology, Washington University, St. Louis, Missouri 63130
| | - Elizabeth M Frick
- Department of Biology, Washington University, St. Louis, Missouri 63130
| | - Emma January
- Department of Biology, Washington University, St. Louis, Missouri 63130
| | - Sarah C Kloepper
- Department of Biology, Washington University, St. Louis, Missouri 63130
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82
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Steffens B. The role of ethylene and ROS in salinity, heavy metal, and flooding responses in rice. FRONTIERS IN PLANT SCIENCE 2014; 5:685. [PMID: 25538719 PMCID: PMC4255495 DOI: 10.3389/fpls.2014.00685] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 11/18/2014] [Indexed: 05/18/2023]
Abstract
Plant growth and developmental processes as well as abiotic and biotic stress adaptations are regulated by small endogenous signaling molecules. Among these, phytohormones such as the gaseous alkene ethylene and reactive oxygen species (ROS) play an important role in mediating numerous specific growth or cell death responses. While apoplastic ROS are generated by plasma membrane-located respiratory burst oxidase homolog proteins, intracellular ROS are produced mainly in electron transfer chains of mitochondria and chloroplasts. Ethylene accumulates in plants due to physical entrapment or by enhanced ethylene biosynthesis. A major crop that must endure high salt and heavy metal concentrations upon flooding in regions of Asia is rice. Ethylene and ROS have been identified as the major signals that mediate salinity, chromium, and flooding stress in rice. This mini review focuses on (i) what is known about ethylene and ROS level control during these abiotic stresses in rice, (ii) how the two signals mediate growth or death processes, and (iii) feedback mechanisms that in turn regulate ethylene and ROS signaling.
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Affiliation(s)
- Bianka Steffens
- *Correspondence: Bianka Steffens, Department of Plant Physiology, Faculty of Biology, Philipps University, Karl-von-Frisch-Strasse 8, 35043 Marburg, Germany e-mail:
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83
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Dawood T, Rieu I, Wolters-Arts M, Derksen EB, Mariani C, Visser EJW. Rapid flooding-induced adventitious root development from preformed primordia in Solanum dulcamara. AOB PLANTS 2014; 6:plt058. [PMID: 24790121 PMCID: PMC3922303 DOI: 10.1093/aobpla/plt058] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 12/15/2013] [Indexed: 05/17/2023]
Abstract
Flooding is a common stress factor in both natural and agricultural systems, and affects plant growth by the slow diffusion rate of gases in water. This results in low oxygen concentrations in submerged tissues, and hence in a decreased respiration rate. Understanding the responses of plants to flooding is essential for the management of wetland ecosystems, and may benefit research to improve the flood tolerance of crop species. This study describes the response to partial submergence of bittersweet (Solanum dulcamara). Bittersweet is a Eurasian species that grows both in dry habitats such as coastal dunes, and in wetlands, and therefore is a suitable model plant for studying responses to a variety of environmental stresses. A further advantage is that the species is closely related to flood-intolerant crops such as tomato and eggplant. The species constitutively develops dormant primordia on the stem, which we show to have a predetermined root identity. We investigated adventitious root growth from these primordia during flooding. The synchronized growth of roots from the primordia was detected after 2-3 days of flooding and was due to a combination of cell division and cell elongation. Gene expression analysis demonstrated that the molecular response to flooding began within 2 h and included activation of hypoxia and ethylene signalling genes. Unexpectedly, these early changes in gene expression were very similar in primordia and adjacent stem tissue, suggesting that there is a dominant general response in tissues during early flooding.
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Affiliation(s)
- Thikra Dawood
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Ivo Rieu
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Mieke Wolters-Arts
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Emiel B. Derksen
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Celestina Mariani
- Department of Molecular Plant Physiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Eric J. W. Visser
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
- Corresponding author's e-mail address:
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84
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Yamauchi T, Watanabe K, Fukazawa A, Mori H, Abe F, Kawaguchi K, Oyanagi A, Nakazono M. Ethylene and reactive oxygen species are involved in root aerenchyma formation and adaptation of wheat seedlings to oxygen-deficient conditions. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:261-73. [PMID: 24253196 PMCID: PMC3883296 DOI: 10.1093/jxb/ert371] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Exposing plants to hypoxic conditions greatly improves their anoxic stress tolerance by enhancing the activities of glycolysis and fermentation in roots. Ethylene may also be involved in these adaptive responses because its synthesis is increased in roots under hypoxic conditions. Here it is reported that pre-treatment of wheat seedlings with an ethylene precursor, 1-aminocyclopropanecarboxylic acid (ACC), enhanced accumulation of ethylene in the roots of wheat seedlings, and enhanced their tolerance of oxygen-deficient conditions through increasing the expression of genes encoding ethanol fermentation enzymes, alcohol dehydrogenase and pyruvate decarboxylase, in the roots. Lysigenous aerenchyma formation in root was induced by ACC pre-treatment and was further induced by growth under oxygen-deficient conditions. ACC pre-treatment increased the expression of three genes encoding respiratory burst oxidase homologue (a plant homologue of gp91(phox) in NADPH oxidase), which has a role in the generation of reactive oxygen species (ROS), in roots of seedlings. Co-treatment with ACC and an NADPH oxidase inhibitor, diphenyleneiodonium, partly suppressed the ACC-induced responses. These results suggest that ethylene and ROS are involved in adaptation of wheat seedlings to oxygen-deficient conditions through controlling lysigenous aerenchyma formation and the expression of genes encoding ethanol fermentation enzymes.
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Affiliation(s)
- Takaki Yamauchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan
| | - Kohtaro Watanabe
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan
| | - Aya Fukazawa
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan
| | - Hitoshi Mori
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan
| | - Fumitaka Abe
- NARO Institute of Crop Science, 2-1-18, Kannondai, Tsukuba, Ibaraki 305-8518, Japan
| | - Kentaro Kawaguchi
- NARO Institute of Crop Science, 2-1-18, Kannondai, Tsukuba, Ibaraki 305-8518, Japan
| | - Atsushi Oyanagi
- NARO Institute of Crop Science, 2-1-18, Kannondai, Tsukuba, Ibaraki 305-8518, Japan
| | - Mikio Nakazono
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8601, Japan
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85
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Ma B, He SJ, Duan KX, Yin CC, Chen H, Yang C, Xiong Q, Song QX, Lu X, Chen HW, Zhang WK, Lu TG, Chen SY, Zhang JS. Identification of rice ethylene-response mutants and characterization of MHZ7/OsEIN2 in distinct ethylene response and yield trait regulation. MOLECULAR PLANT 2013; 6:1830-48. [PMID: 23718947 DOI: 10.1093/mp/sst087] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Ethylene plays essential roles in adaptive growth of rice plants in water-saturating environment; however, ethylene signaling pathway in rice is largely unclear. In this study, we report identification and characterization of ethylene-response mutants based on the specific ethylene-response phenotypes of etiolated rice seedlings, including ethylene-inhibited root growth and ethylene-promoted coleoptile elongation, which is different from the ethylene triple-response phenotype in Arabidopsis. We establish an efficient system for screening and a set of rice mutants have been identified. Genetic analysis reveals that these mutants form eight complementation groups. All the mutants show insensitivity or reduced sensitivity to ethylene in root growth but exhibit differential responses in coleoptile growth. One mutant group mhz7 has insensitivity to ethylene in both root and coleoptile growth. We identified the corresponding gene by a map-based cloning method. MHZ7 encodes a membrane protein homologous to EIN2, a central component of ethylene signaling in Arabidopsis. Upon ethylene treatment, etiolated MHZ7-overexpressing seedlings exhibit enhanced coleoptile elongation, increased mesocotyl growth and extremely twisted short roots, featuring enhanced ethylene-response phenotypes in rice. Grain length was promoted in MHZ7-transgenic plants and 1000-grain weight was reduced in mhz7 mutants. Leaf senescent process was also affected by MHZ7 expression. Manipulation of ethylene signaling may improve adaptive growth and yield-related traits in rice.
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Affiliation(s)
- Biao Ma
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
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86
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Voesenek LACJ, Bailey-Serres J. Flooding tolerance: O2 sensing and survival strategies. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:647-653. [PMID: 23830867 DOI: 10.1016/j.pbi.2013.06.008] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/11/2013] [Accepted: 06/11/2013] [Indexed: 05/28/2023]
Abstract
The investigation of flooding survival strategies in model, crop and wild plant species has yielded insights into molecular, physiological and developmental mechanisms of soil flooding (waterlogging) and submergence survival. The antithetical flooding escape and quiescence strategies of deepwater and submergence tolerant rice (Oryza sativa), respectively, are regulated by members of a clade of ethylene responsive factor transcriptional activators. This knowledge paved the way for the discovery that these proteins are targets of a highly conserved O2-sensing protein turnover mechanism in Arabidopsis thaliana. Further examples of genes that regulate transcription, root and shoot metabolism or development during floods have emerged. With the rapid advancement of genomic technologies, the mining of natural genetic variation in flooding tolerant wild species may ultimately benefit crop production.
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Affiliation(s)
- L A C J Voesenek
- Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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87
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Orman-Ligeza B, Parizot B, Gantet PP, Beeckman T, Bennett MJ, Draye X. Post-embryonic root organogenesis in cereals: branching out from model plants. TRENDS IN PLANT SCIENCE 2013; 18:459-67. [PMID: 23727199 DOI: 10.1016/j.tplants.2013.04.010] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 04/23/2013] [Accepted: 04/29/2013] [Indexed: 05/07/2023]
Abstract
The root architecture of higher plants is amazingly diverse. In this review, we compare the lateral root developmental programme in cereals and Arabidopsis thaliana. In cereals, cells in the endodermis are recruited to form the new root cap and overlying cortical cells divide to facilitate the emergence of the lateral root primordium. The TIR1/ABF2 auxin receptors and the AUX/IAA, ARF, and LBD transcriptional regulatory proteins are conserved in cereals and Arabidopsis. Several elements of this regulatory network are common to lateral and crown roots in cereals. Also, the ground meristem from which crown roots differentiate shows similarities with the root pericycle. Studies in cereals promise to give complementary insights into the mechanisms regulating the development of post-embryonic roots in plants.
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Affiliation(s)
- Beata Orman-Ligeza
- Université catholique de Louvain, Earth and Life Institute, Louvain-la-Neuve, Belgium
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88
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Hardham AR. Microtubules and biotic interactions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 75:278-89. [PMID: 23480445 DOI: 10.1111/tpj.12171] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 02/20/2013] [Accepted: 03/04/2013] [Indexed: 05/06/2023]
Abstract
Plant microtubules undergo extensive reorganization in response to symbiotic and pathogenic organisms. During the development of successful symbioses with rhizobia and mycorrhizal fungi, novel microtubule arrays facilitate the progression of infection threads and hyphae, respectively, from the plant surface through epidermal and cortical cells. During viral and nematode infections, plant microtubules appear to be commandeered by the pathogen. Viruses use plant microtubules for intra and intercellular movement, as well as for interhost transmission. Nematodes manipulate spindle and phragmoplast microtubules to enhance mitosis and partial cytokinesis during the development of syncytia and giant cells. Pathogenic bacteria, fungi and oomycetes induce a range of alterations to microtubule arrays and dynamics. In many situations, the pathogen, or the elicitor or effector proteins derived from them, induce depolymerization of plant cortical microtubule arrays. In some cases, microtubule disruption is associated with the plant defence response and resistance. In other cases, microtubule depolymerization increases plant susceptibility to the invading pathogen. The reasons for this apparent inconsistency may depend on a number of factors, in particular on the identity of the organism orchestrating the microtubule changes. Overall, the weight of evidence indicates that microtubules play an important role in both the establishment of functional symbioses and in defence against invading pathogens. Research is beginning to unravel details about the nature of both the chemical and the mechanical signals to which the plant microtubule arrays respond during biotic interactions.
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Affiliation(s)
- Adrienne R Hardham
- Plant Science Division, Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT 2600, Australia.
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89
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Sauter M. Root responses to flooding. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:282-6. [PMID: 23608517 DOI: 10.1016/j.pbi.2013.03.013] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 03/26/2013] [Accepted: 03/27/2013] [Indexed: 05/04/2023]
Abstract
Soil water-logging and submergence pose a severe threat to plants. Roots are most prone to flooding and the first to suffer from oxygen shortage. Roots are vital for plant function, however, and maintenance of a functional root system upon flooding is essential. Flooding-resistant plants possess a number of adaptations that help maintain oxygen supply to the root. Plants are also capable of initiating organogenesis to replace their original root system with adventitious roots if oxygen supply becomes impossible. This review summarizes current findings on root development and de novo root genesis in response to flooding.
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Affiliation(s)
- Margret Sauter
- Plant Developmental Biology and Plant Physiology, Kiel University, Am Botanischen Garten 5, 24118 Kiel, Germany.
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90
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Fukao T, Xiong L. Genetic mechanisms conferring adaptation to submergence and drought in rice: simple or complex? CURRENT OPINION IN PLANT BIOLOGY 2013; 16:196-204. [PMID: 23453780 DOI: 10.1016/j.pbi.2013.02.003] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 02/04/2013] [Accepted: 02/05/2013] [Indexed: 05/22/2023]
Abstract
Both high and low extremes in precipitation increasingly impact agricultural productivity and sustainability as a consequence of global climate change. Elucidation of the genetic basis underlying stress tolerance facilitates development of new rice varieties with enhanced tolerance. Submergence tolerance is conferred by a single master regulator that orchestrates various acclimation responses, whereas drought tolerance is regulated by a number of small-effect loci that are largely influenced by genetic background and environment. Detailed molecular studies have uncovered the functional importance of genes and signaling components which coordinate various morphological and physiological responses to submergence and drought, providing new insight into understanding the complex regulatory mechanisms of stress tolerance in rice.
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Affiliation(s)
- Takeshi Fukao
- Department of Crop and Soil Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA.
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91
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Sundaravelpandian K, Chandrika NNP, Tsai YH, Schmidt W. PFT1-controlled ROS balance is critical for multiple stages of root hair development in Arabidopsis. PLANT SIGNALING & BEHAVIOR 2013; 8:e24066. [PMID: 23455023 PMCID: PMC3907413 DOI: 10.4161/psb.24066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Reactive oxygen species (ROS) have been shown to play key roles in cellular decision making and signal integration in multicellular organisms. In roots, ROS levels are managed by the action of peroxidases and NAPDH oxidases, resulting in a distinct spatial distribution of hydrogen peroxide (H₂O₂) and superoxide (O₂(-)) that is critical for the balance between cell proliferation and differentiation. In addition, ROS is required for the determination of the cell shape of root hairs. Mutations in the Mediator subunit MED25/PFT1 result in compromised root hair development, due to altered expression of a suite of H₂O₂-producing class III peroxidases. pft1-1 mutants form shorter root hairs than wild-type plants. Analysis of pft1-1 cross-sections revealed that also root hair initiation is compromised, probably by impeding local cell wall loosening. It is suggested that ROS homeostasis is critical throughout the development of root hairs, controlling various processes via PFT1-regulated transcription of genes encoding redox-active enzymes.
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Affiliation(s)
- Kalaipandian Sundaravelpandian
- Institute of Plant and Microbial Biology; Academia Sinica; Taipei, Taiwan
- Molecular and Biological Agricultural Sciences; Taiwan International Graduate Program; National Chung Hsing University-Academia Sinica; Taipei, Taiwan
- Graduate Institute of Biotechnology; National Chung-Hsing University; Taichung, Taiwan
| | - Nulu Naga Prafulla Chandrika
- Institute of Plant and Microbial Biology; Academia Sinica; Taipei, Taiwan
- Molecular and Cell Biology; Taiwan International Graduate Program; Academia Sinica; National Defense Medical Center; Taipei, Taiwan
| | - Yi-Hsiu Tsai
- Institute of Plant and Microbial Biology; Academia Sinica; Taipei, Taiwan
| | - Wolfgang Schmidt
- Institute of Plant and Microbial Biology; Academia Sinica; Taipei, Taiwan
- Molecular and Biological Agricultural Sciences; Taiwan International Graduate Program; National Chung Hsing University-Academia Sinica; Taipei, Taiwan
- Graduate Institute of Biotechnology; National Chung-Hsing University; Taichung, Taiwan
- Molecular and Cell Biology; Taiwan International Graduate Program; Academia Sinica; National Defense Medical Center; Taipei, Taiwan
- Genome and Systems Biology Degree Program; College of Life Science; National Taiwan University; Taipei, Taiwan
- Correspondence to: Wolfgang Schmidt,
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Steffens B, Steffen-Heins A, Sauter M. Reactive oxygen species mediate growth and death in submerged plants. FRONTIERS IN PLANT SCIENCE 2013; 4:179. [PMID: 23761805 PMCID: PMC3671184 DOI: 10.3389/fpls.2013.00179] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 05/17/2013] [Indexed: 05/07/2023]
Abstract
Aquatic and semi-aquatic plants are well adapted to survive partial or complete submergence which is commonly accompanied by oxygen deprivation. The gaseous hormone ethylene controls a number of adaptive responses to submergence including adventitious root growth and aerenchyma formation. Reactive oxygen species (ROS) act as signaling intermediates in ethylene-controlled submergence adaptation and possibly also independent of ethylene. ROS levels are controlled by synthesis, enzymatic metabolism, and non-enzymatic scavenging. While the actors are by and large known, we still have to learn about altered ROS at the subcellular level and how they are brought about, and the signaling cascades that trigger a specific response. This review briefly summarizes our knowledge on the contribution of ROS to submergence adaptation and describes spectrophotometrical, histochemical, and live cell imaging detection methods that have been used to study changes in ROS abundance. Electron paramagnetic resonance (EPR) spectroscopy is introduced as a method that allows identification and quantification of specific ROS in cell compartments. The use of advanced technologies such as EPR spectroscopy will be necessary to untangle the intricate and partially interwoven signaling networks of ethylene and ROS.
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Affiliation(s)
- Bianka Steffens
- Plant Developmental Biology and Plant Physiology, Kiel UniversityKiel, Germany
- *Correspondence: Bianka Steffens, Plant Developmental Biology and Plant Physiology, Kiel University, Am Botanischen Garten 5, 24118 Kiel, Germany e-mail:
| | | | - Margret Sauter
- Plant Developmental Biology and Plant Physiology, Kiel UniversityKiel, Germany
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Bailey-Serres J, Lee SC, Brinton E. Waterproofing crops: effective flooding survival strategies. PLANT PHYSIOLOGY 2012; 160:1698-709. [PMID: 23093359 PMCID: PMC3510103 DOI: 10.1104/pp.112.208173] [Citation(s) in RCA: 218] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 10/22/2012] [Indexed: 05/17/2023]
Affiliation(s)
- Julia Bailey-Serres
- Center for Plant Cell Biology, Department of Botany and Plant Science, University of California, Riverside, California 92521-0124, USA.
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