27 results on '"Dong-Wei Di"'
Search Results
2. The Roles of GRETCHEN HAGEN3 (GH3)-Dependent Auxin Conjugation in the Regulation of Plant Development and Stress Adaptation
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Pan Luo, Ting-Ting Li, Wei-Ming Shi, Qi Ma, and Dong-Wei Di
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auxin ,IAA ,GH3 ,chemical inhibitor ,transcriptional regulation ,Botany ,QK1-989 - Abstract
The precise control of free auxin (indole-3-acetic acid, IAA) gradient, which is orchestrated by biosynthesis, conjugation, degradation, hydrolyzation, and transport, is critical for all aspects of plant growth and development. Of these, the GRETCHEN HAGEN 3 (GH3) acyl acid amido synthetase family, pivotal in conjugating IAA with amino acids, has garnered significant interest. Recent advances in understanding GH3-dependent IAA conjugation have positioned GH3 functional elucidation as a hot topic of research. This review aims to consolidate and discuss recent findings on (i) the enzymatic mechanisms driving GH3 activity, (ii) the influence of chemical inhibitor on GH3 function, and (iii) the transcriptional regulation of GH3 and its impact on plant development and stress response. Additionally, we explore the distinct biological functions attributed to IAA-amino acid conjugates.
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- 2023
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3. New Molecular Mechanisms of Plant Response to Ammonium Nutrition
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Dong-Wei Di
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n/a ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Ammonium (NH4+) and nitrate (NO3−) are two major inorganic nitrogen (N) forms for plants [...]
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- 2023
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4. The roles of epigenetic modifications in the regulation of auxin biosynthesis
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Jun-Li Wang, Dong-Wei Di, Pan Luo, Li Zhang, Xiao-Feng Li, Guang-Qin Guo, and Lei Wu
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auxin biosynthesis ,epigenetic modifications ,histone H3 methylation ,histone acetylation ,chromatin remodeling ,histone H2B monoubiquitination ,Plant culture ,SB1-1110 - Abstract
Auxin is one of the most important plant growth regulators of plant morphogenesis and response to environmental stimuli. Although the biosynthesis pathway of auxin has been elucidated, the mechanisms regulating auxin biosynthesis remain poorly understood. The transcription of auxin biosynthetic genes is precisely regulated by complex signaling pathways. When the genes are expressed, epigenetic modifications guide mRNA synthesis and therefore determine protein production. Recent studies have shown that different epigenetic factors affect the transcription of auxin biosynthetic genes. In this review, we focus our attention on the molecular mechanisms through which epigenetic modifications regulate auxin biosynthesis.
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- 2022
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5. Precise Regulation of the TAA1/TAR-YUCCA Auxin Biosynthesis Pathway in Plants
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Pan Luo and Dong-Wei Di
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IPA pathway ,transcriptional regulation ,protein modification ,feedback regulation ,regulatory mechanism ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The indole-3-pyruvic acid (IPA) pathway is the main auxin biosynthesis pathway in the plant kingdom. Local control of auxin biosynthesis through this pathway regulates plant growth and development and the responses to biotic and abiotic stresses. During the past decades, genetic, physiological, biochemical, and molecular studies have greatly advanced our understanding of tryptophan-dependent auxin biosynthesis. The IPA pathway includes two steps: Trp is converted to IPA by TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS/TRYPTOPHAN AMINOTRANSFERASE RELATED PROTEINs (TAA1/TARs), and then IPA is converted to IAA by the flavin monooxygenases (YUCCAs). The IPA pathway is regulated at multiple levels, including transcriptional and post-transcriptional regulation, protein modification, and feedback regulation, resulting in changes in gene transcription, enzyme activity and protein localization. Ongoing research indicates that tissue-specific DNA methylation and miRNA-directed regulation of transcription factors may also play key roles in the precise regulation of IPA-dependent auxin biosynthesis in plants. This review will mainly summarize the regulatory mechanisms of the IPA pathway and address the many unresolved questions regarding this auxin biosynthesis pathway in plants.
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- 2023
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6. Function of histone H2B monoubiquitination in transcriptional regulation of auxin biosynthesis in Arabidopsis
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Li Zhang, Pan Luo, Jie Bai, Lei Wu, Dong-Wei Di, Hai-Qing Liu, Jing-Jing Li, Ya-Li Liu, Allah Jurio Khaskheli, Chang-Ming Zhao, and Guang-Qin Guo
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Biology (General) ,QH301-705.5 - Abstract
Li Zhang et al. characterize ckrw2, cytokinin-induced root waving 2, as a mutant form of HUB1 in Arabidopsis, the gene required for histone H2B monoubiquitination. This study implicates the involvement of H2Bub1 in regulating auxin biosynthesis.
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- 2021
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7. WAV E3 ubiquitin ligases mediate degradation of IAA32/34 in the TMK1-mediated auxin signaling pathway during apical hook development.
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Jun-Li Wang, Ming Wang, Li Zhang, You-Xi Li, Jing-Jing Li, Yu-Yang Li, Zuo-Xian Pu, Dan-Yang Li, Xing-Nan Liu, Wang Guo, Dong-Wei Di, Xiao-Feng Li, Guang-Qin Guo, and Lei Wu
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UBIQUITIN ligases ,AUXIN ,CELLULAR signal transduction ,HOOKS ,PLANT growth - Abstract
Auxin regulates plant growth and development through downstream signaling pathways, including the best-known SCFTIR1/AFB-Aux/IAA-ARF pathway and several other less characterized "noncanonical" pathways. Recently, one SCFTIR1/AFB-independent noncanonical pathway, mediated by Transmembrane Kinase 1 (TMK1), was discovered through the analyses of its functions in Arabidopsis apical hook development. Asymmetric accumulation of auxin on the concave side of the apical hook triggers DAR1-catalyzed release of the C-terminal of TMK1, which migrates into the nucleus, where it phosphorylates and stabilizes IAA32/34 to inhibit cell elongation, which is essential for full apical hook formation. However, the molecular factors mediating IAA32/34 degradation have not been identified. Here, we show that proteins in the CYTOKININ INDUCED ROOT WAVING 1 (CKRW1)/WAVY GROWTH 3 (WAV3) subfamily act as E3 ubiquitin ligases to target IAA32/34 for ubiquitination and degradation, which is inhibited by TMK1c-mediated phosphorylation. This antagonistic interaction between TMK1c and CKRW1/WAV3 subfamily E3 ubiquitin ligases regulates IAA32/34 levels to control differential cell elongation along opposite sides of the apical hook. [ABSTRACT FROM AUTHOR]
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- 2024
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8. PIN5 is involved in regulating NH4+ efflux and primary root growth under high-ammonium stress via mediating intracellular auxin transport
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Dong-Wei Di, Jingjing Wu, Mingkun Ma, Guangjie Li, Meng Wang, Herbert J. Kronzucker, and Weiming Shi
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Soil Science ,Plant Science - Published
- 2023
9. Endogenous ABA alleviates rice ammonium toxicity by reducing ROS and free ammonium via regulation of the SAPK9–bZIP20 pathway
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Herbert J. Kronzucker, Xiangyu Wu, Guangjie Li, Li Sun, Dong-Wei Di, and Weiming Shi
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inorganic chemicals ,Antioxidant ,Physiology ,medicine.medical_treatment ,OsbZIP20 ,Mutant ,antioxidant activity ,Plant Science ,medicine.disease_cause ,chemistry.chemical_compound ,Glutamate-Ammonia Ligase ,Glutamine synthetase ,Ammonium Compounds ,medicine ,ammonium assimilation ,Ammonium ,Abscisic acid ,chemistry.chemical_classification ,Reactive oxygen species ,Oryza sativa ,AcademicSubjects/SCI01210 ,fungi ,food and beverages ,high ammonium stress ,Oryza ,Research Papers ,OsSAPK9 ,ABA ,chemistry ,Biochemistry ,Reactive Oxygen Species ,Oxidative stress ,Abscisic Acid - Abstract
Abscisic acid plays a positive role in regulating the OsSAPK9–OsbZIP20 pathway and elevating antioxidant and GS/GOGAT activities in rice to increase tolerance to high-NH4+ stress., Ammonium (NH4+) is one of the principal nitrogen (N) sources in soils, but is typically toxic already at intermediate concentrations. The phytohormone abscisic acid (ABA) plays a pivotal role in responses to environmental stresses. However, the role of ABA under high-NH4+ stress in rice (Oryza sativa L.) is only marginally understood. Here, we report that elevated NH4+ can significantly accelerate tissue ABA accumulation. Mutants with high (Osaba8ox) and low levels of ABA (Osphs3-1) exhibit elevated tolerance or sensitivity to high-NH4+ stress, respectively. Furthermore, ABA can decrease NH4+-induced oxidative damage and tissue NH4+ accumulation by enhancing antioxidant and glutamine synthetase (GS)/glutamate synthetasae (GOGAT) enzyme activities. Using RNA sequencing and quantitative real-time PCR approaches, we ascertain that two genes, OsSAPK9 and OsbZIP20, are induced both by high NH4+ and by ABA. Our data indicate that OsSAPK9 interacts with OsbZIP20, and can phosphorylate OsbZIP20 and activate its function. When OsSAPK9 or OsbZIP20 are knocked out in rice, ABA-mediated antioxidant and GS/GOGAT activity enhancement under high-NH4+ stress disappear, and the two mutants are more sensitive to high-NH4+ stress compared with their wild types. Taken together, our results suggest that ABA plays a positive role in regulating the OsSAPK9–OsbZIP20 pathway in rice to increase tolerance to high-NH4+ stress.
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- 2020
10. WRKY46 promotes ammonium tolerance in Arabidopsis by repressing NUDX9 and indole-3-acetic acid-conjugating genes and by inhibiting ammonium efflux in the root elongation zone
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Li Sun, Jinfang Chu, Dong-Wei Di, Herbert J. Kronzucker, Jingjing Wu, Guangjie Li, Meng Wang, Shuang Fang, and Weiming Shi
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inorganic chemicals ,Regulation of gene expression ,biology ,Indoleacetic Acids ,Physiology ,Arabidopsis Proteins ,Arabidopsis ,food and beverages ,Promoter ,Plant Science ,biology.organism_classification ,Plant Roots ,Cell biology ,chemistry.chemical_compound ,chemistry ,Transcription (biology) ,Gene Expression Regulation, Plant ,Ammonium Compounds ,Transcriptional regulation ,Efflux ,Indole-3-acetic acid ,Transcription factor - Abstract
Ammonium (NH4 + ) is toxic to root growth in most plants, even at moderate concentrations. Transcriptional regulation is one of the most important mechanisms in the response of plants to NH4 + toxicity, but the nature of the involvement of transcription factors (TFs) in this regulation remains unclear. Here, RNA-seq analysis was performed on Arabidopsis roots to screen for ammonium-responsive TFs. WRKY46, the member of the WRKY transcription factor family most responsive to NH4 + , was selected. We defined the role of WRKY46 using mutation and overexpression assays, and characterized the regulation of NUDX9 and indole-3-acetic acid (IAA)-conjugating genes by WRKY46 via yeast one-hybrid and electrophoretic mobility shift assays and chromatin immunoprecipitation-quantitative real-time polymerase chain reaction (ChIP-qPCR). Knockout of WRKY46 increased, while overexpression of WRKY46 decreased, NH4 + -suppression of the primary root. WRKY46 is shown to directly bind to the promoters of the NUDX9 and IAA-conjugating genes (GH3.1, GH3.6, UGT75D1, UGT84B2) and to inhibit their transcription, thus positively regulating free IAA content and stabilizing protein N-glycosylation, leading to an inhibition of NH4 + efflux in the root elongation zone (EZ). We identify TF involvement in the regulation of NH4 + efflux in the EZ, and show that WRKY46 inhibits NH4 + efflux by negative regulation of NUDX9 and IAA-conjugating genes.
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- 2021
11. High ammonium inhibits root growth in Arabidopsis thaliana by promoting auxin conjugation rather than inhibiting auxin biosynthesis
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Shuang Fang, Jingjing Wu, Guangjie Li, Meng Wang, Dong-Wei Di, Li Sun, Jinfang Chu, Weiming Shi, and Herbert J. Kronzucker
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0106 biological sciences ,0301 basic medicine ,Physiology ,Mutant ,Arabidopsis ,Plant Science ,01 natural sciences ,Plant Roots ,03 medical and health sciences ,chemistry.chemical_compound ,Biosynthesis ,Auxin ,Stress, Physiological ,Ammonium Compounds ,Arabidopsis thaliana ,Homeostasis ,heterocyclic compounds ,Ammonium ,Gene ,chemistry.chemical_classification ,biology ,Indoleacetic Acids ,food and beverages ,biology.organism_classification ,Cell biology ,030104 developmental biology ,chemistry ,Elongation ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Ammonium (NH4+) inhibits primary root (PR) growth in most plant species when present even at moderate concentrations. Previous studies have shown that transport of indole-3-acetic acid (IAA) is critical to maintaining root elongation under high-NH4+ stress. However, the precise regulation of IAA homeostasis under high-NH4+ stress (HAS) remains unclear. In this study, qRT-PCR, RNA-seq, free IAA and IAA conjugate and PR elongation measurements were conducted in genetic mutants to investigate the role of IAA biosynthesis and conjugation under HAS. Our data clearly show that HAS decreases free IAA in roots by increasing IAA inactivation but does not decrease IAA biosynthesis, and that the IAA-conjugating genes GH3.1, GH3.2, GH3.3, GH3.4, and GH3.6 function as the key genes in regulating high-NH4+ sensitivity in the roots. Furthermore, the analysis of promoter::GUS staining in situ and genetic mutants reveals that HAS promotes IAA conjugation in the elongation zone (EZ), which may be responsible for the PR inhibition observed under HAS. This study provides potential new insight into the role of auxin in the improvement of tolerance to NH4+.
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- 2021
12. Precise control of ABA signaling through post-translational protein modification
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Lei Wu, Dong-Wei Di, Li Zhang, Muhammad Tariq Hafeez, and Jing Zhang
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0106 biological sciences ,0301 basic medicine ,Physiology ,Kinase ,organic chemicals ,fungi ,food and beverages ,Plant Science ,Protein degradation ,01 natural sciences ,Cell biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Phosphorylation ,Protein phosphorylation ,Signal transduction ,Post-translational protein modification ,Agronomy and Crop Science ,Abscisic acid ,Transcription factor ,010606 plant biology & botany - Abstract
Abscisic acid (ABA) plays a key role in plant growth and development and during stress responses. Plants respond to ABA through recognition, signal transduction, and response cascades. The core ABA signaling pathway consists of ABA receptors (RCAR/PYL/PYRs), protein phosphatases (PP2Cs), kinases (SnRK2s), transcription factors and ion channel proteins. Protein phosphorylation plays a key role in this pathway. In the absence of ABA, PP2Cs inhibit SnRK2s activities by dephosphorylating SnRK2s. When ABA binds to RCAR/PYL/PYRs, the complex then binds to PP2Cs, resulting in inactivation of the PP2Cs and release of the SnRK2s, which then phosphorylate a series of substrates to activate ABA responses. Selective protein degradation by the ubiquitin–proteasome system also contributes to regulation of ABA homeostasis, transport, signaling, and desensitization. The small ubiquitin-like modifier (SUMO) enhances the stability of ABI5 but also inhibits its transcription. ABA-induced reactive nitrogen and oxygen species regulate multiple key components of the ABA signaling pathways through redox-induced modifications (REDOX), such as oxidation, nitration, and nitrosylation, forming a feedback regulation mechanism that precisely regulates ABA signaling. This review will detail the role of these post-translational modifications in the core ABA signaling pathway.
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- 2019
13. Involvement of auxin in the regulation of ammonium tolerance in rice (Oryza sativa L.)
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Herbert J. Kronzucker, Xiaonan Zhang, Weiming Shi, Li Sun, Dong-Wei Di, and Guangjie Li
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inorganic chemicals ,0106 biological sciences ,0301 basic medicine ,chemistry.chemical_classification ,Oryza sativa ,Auxin homeostasis ,Chemistry ,fungi ,food and beverages ,Soil Science ,Plant physiology ,Plant Science ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Biosynthesis ,Auxin ,Shoot ,Botany ,heterocyclic compounds ,Ammonium ,Abscisic acid ,010606 plant biology & botany - Abstract
Ammonium (NH4+) is an important nitrogen source and is widely used as a fertilizer in agricultural systems. However, excess NH4+ inhibits root growth, and, subsequently, vegetative shoot growth and yield. This study examines whether auxin is involved in differential NH4+ tolerance in rice (Oryza sativa L.), and how auxin is regulated under high-NH4+ conditions in rice. An NH4+-sensitive (Kasalath, Kas) and an NH4+-insensitive (Koshihikari, Kos) rive cultivar were cultured hydroponically with or without exogenous indole-3-acetic acid (IAA) and auxin biosynthesis inhibitors. Root growth, root area, tissue IAA content, and transcription of genes involved in auxin biosynthesis, conjugation and degradation were determined. pDR5::GUS staining and auxin measurement show that high NH4+ can decrease free IAA content in roots. In addition, quantitative RT-PCR, pharmacology, and genetics analysis suggest that Kos possesses a higher capacity for auxin biosynthesis and a weaker capacity for auxin metabolism compared to Kas under high-NH4+ stress. We conclude that the NH4+-tolerant cultivar possesses a higher capacity to maintain auxin homeostasis under high-NH4+ stress, and that this advantage is incurred by promotion of auxin biosynthesis and a suppression of auxin metabolism.
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- 2018
14. Induction of S-nitrosoglutathione reductase protects root growth from ammonium toxicity by regulating potassium homeostasis in Arabidopsis and rice
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Weiming Shi, Lin Zhang, Herbert J. Kronzucker, Dong-Wei Di, Xianyong Lin, Baohai Li, Haiyan Song, Meng Wang, and Guangjie Li
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inorganic chemicals ,0106 biological sciences ,0301 basic medicine ,Vitamin ,Physiology ,Potassium ,Arabidopsis ,chemistry.chemical_element ,Plant Science ,Reductase ,01 natural sciences ,Nitric oxide ,03 medical and health sciences ,chemistry.chemical_compound ,Ammonium Compounds ,Homeostasis ,Ammonium ,biology ,Chemistry ,Arabidopsis Proteins ,food and beverages ,Oryza ,biology.organism_classification ,Aldehyde Oxidoreductases ,Cell biology ,030104 developmental biology ,Glutathione Reductase ,Toxicity ,S-Nitrosoglutathione ,Oxidoreductases ,010606 plant biology & botany - Abstract
Ammonium (NH4+) is toxic to root growth in most plants already at moderate levels of supply, but mechanisms of root growth tolerance to NH4+ remain poorly understood. Here, we report that high levels of NH4+ induce nitric oxide (NO) accumulation, while inhibiting potassium (K+) acquisition via SNO1 (sensitive to nitric oxide 1)/SOS4 (salt overly sensitive 4), leading to the arrest of primary root growth. High levels of NH4+ also stimulated the accumulation of GSNOR (S-nitrosoglutathione reductase) in roots. GSNOR overexpression improved root tolerance to NH4+. Loss of GSNOR further induced NO accumulation, increased SNO1/SOS4 activity, and reduced K+ levels in root tissue, enhancing root growth sensitivity to NH4+. Moreover, the GSNOR-like gene, OsGSNOR, is also required for NH4+ tolerance in rice. Immunoblotting showed that the NH4+-induced GSNOR protein accumulation was abolished in the VTC1- (vitamin C1) defective mutant vtc1-1, which is hypersensititive to NH4+ toxicity. GSNOR overexpression enhanced vtc1-1 root tolerance to NH4+. Our findings suggest that induction of GSNOR increases NH4+ tolerance in Arabidopsis roots by counteracting NO-mediated suppression of tissue K+, which depends on VTC1 function.
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- 2020
15. Function of histone H2B monoubiquitination in transcriptional regulation of auxin biosynthesis in Arabidopsis
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Allah Jurio Khaskheli, Guang-Qin Guo, Dong-Wei Di, Chang-Ming Zhao, Lei Wu, Jing-Jing Li, Ya-Li Liu, Hai-qing Liu, Li Zhang, Jie Bai, and Pan Luo
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0106 biological sciences ,0301 basic medicine ,Cytokinins ,Transcription, Genetic ,QH301-705.5 ,Histone monoubiquitination ,Ubiquitin-Protein Ligases ,Arabidopsis ,Medicine (miscellaneous) ,Biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Article ,Epigenesis, Genetic ,Histones ,03 medical and health sciences ,Auxin ,Gene Expression Regulation, Plant ,Plant hormones ,Histone post-translational modifications ,Histone H2B ,Monoubiquitination ,heterocyclic compounds ,Biology (General) ,chemistry.chemical_classification ,Auxin homeostasis ,Indoleacetic Acids ,Arabidopsis Proteins ,fungi ,Ubiquitination ,food and beverages ,biology.organism_classification ,Chromatin Assembly and Disassembly ,Plants, Genetically Modified ,Chromatin ,Cell biology ,030104 developmental biology ,chemistry ,General Agricultural and Biological Sciences ,Chromatin immunoprecipitation ,010606 plant biology & botany - Abstract
The auxin IAA is a vital plant hormone in controlling growth and development, but our knowledge about its complicated biosynthetic pathways and molecular regulation are still limited and fragmentary. cytokinin induced root waving 2 (ckrw2) was isolated as one of the auxin-deficient mutants in a large-scale forward genetic screen aiming to find more genes functioning in auxin homeostasis and/or its regulation. Here we show that CKRW2 is identical to Histone Monoubiquitination 1 (HUB1), a gene encoding an E3 ligase required for histone H2B monoubiquitination (H2Bub1) in Arabidopsis. In addition to pleiotropic defects in growth and development, loss of CKRW2/HUB1 function also led to typical auxin-deficient phenotypes in roots, which was associated with significantly lower expression levels of several functional auxin synthetic genes, namely TRP2/TSB1, WEI7/ASB1, YUC7 and AMI1. Corresponding defects in H2Bub1 were detected in the coding regions of these genes by chromatin immunoprecipitation (ChIP) analysis, indicating the involvement of H2Bub1 in regulating auxin biosynthesis. Importantly, application of exogenous cytokinin (CK) could stimulate CKRW2/HUB1 expression, providing an epigenetic avenue for CK to regulate the auxin homeostasis. Our results reveal a previously unknown mechanism for regulating auxin biosynthesis via HUB1/2-mediated H2Bub1 at the chromatin level., Li Zhang et al. characterize ckrw2, cytokinin-induced root waving 2, as a mutant form of HUB1 in Arabidopsis, the gene required for histone H2B monoubiquitination. This study implicates the involvement of H2Bub1 in regulating auxin biosynthesis.
- Published
- 2020
16. Higher nitrogen use efficiency (NUE) in hybrid 'super rice' links to improved morphological and physiological traits in seedling roots
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Weiming Shi, Dong-Wei Di, Gui Chen, Herbert J. Kronzucker, and Mei Chen
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0106 biological sciences ,0301 basic medicine ,Physiology ,Nitrogen ,chemistry.chemical_element ,Plant Science ,Root system ,01 natural sciences ,Plant Roots ,Aerenchyma ,03 medical and health sciences ,chemistry.chemical_compound ,Ammonium ,Cultivar ,biology ,Nutrient management ,food and beverages ,Oryza ,biology.organism_classification ,Horticulture ,Plant Breeding ,030104 developmental biology ,chemistry ,Seedling ,Seedlings ,Hybridization, Genetic ,Elongation ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Great progress has been achieved in developing hybrid "super rice" varieties in China. Understanding morphological root traits in super rice and the mechanisms of nitrogen acquisition by the root system are of fundamental importance to developing proper fertilisation and nutrient management practices in their production. The present study was designed to study morphological and physiological traits in hybrid super rice roots that are associated with nitrogen use efficiency (NUE). Two hybrid super rice varieties (Yongyou12, YY; Jiayou 6, JY) and one common variety (Xiushui 134, XS) with differing NUE were cultivated hydroponically, and morphological and physiological traits of seedling roots in response to varying nitrogen conditions were investigated. Our results show that the hybrid cultivars YY and JY exhibit larger root systems, arising from a maximisation of root tips and from longer roots without changes in root diameter. The cross-sectional proportion of aerenchyma was significantly higher in super rice roots. The larger root system of super hybrid rice contributed to higher N accumulation and resulted in higher N uptake efficiency. 15N (15NH4+) labeling results show that YY and JY had an enhanced capacity for ammonium (NH4+) uptake. Moreover, YY and JY were more tolerant to high NH4+ and showed reduced futile NH4+ efflux. NH4+ efflux in the root elongation zone, measured by Non-invasive Micro-test Technology, was significantly lower than in XS. Taken together, our results suggest that a longer root, a larger number of tips, a better developed aerenchyma, a higher capacity for N uptake, and reduced NH4+ efflux from roots are associated with higher NUE and growth performance in hybrid super rice.
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- 2020
17. TaANR1-TaBG1 and TaWabi5-TaNRT2s/NARs Link ABA Metabolism and Nitrate Acquisition in Wheat Roots
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Guangmin Xia, Meng Wang, Herbert J. Kronzucker, Pengli Zhang, Shuang Fang, Jinfang Chu, Guangjie Li, Dong-Wei Di, Weiming Shi, and Qian Liu
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0106 biological sciences ,Physiology ,Arabidopsis ,Plant Science ,01 natural sciences ,Plant Roots ,chemistry.chemical_compound ,Nutrient ,Nitrate ,Gene Expression Regulation, Plant ,Botany ,Genetics ,Gene family ,Gene ,Abscisic acid ,Research Articles ,Triticum ,Plant Proteins ,Regulation of gene expression ,Nitrates ,biology ,Arabidopsis Proteins ,fungi ,food and beverages ,Metabolism ,biology.organism_classification ,chemistry ,010606 plant biology & botany ,Abscisic Acid - Abstract
Nitrate is the preferred form of nitrogen for most plants, acting both as a nutrient and a signaling molecule. However, the components and regulatory factors governing nitrate uptake in bread wheat (Triticum aestivum), one of the world’s most important crop species, have remained unclear, largely due to the complexity of its hexaploid genome. Here, based on recently released whole-genome information for bread wheat, the high-affinity nitrate transporter2 (NRT2) and the nitrate-assimilation-related (NAR) gene family are characterized. We show that abscisic acid (ABA)- Glc ester deconjugation is stimulated in bread wheat roots by nitrate resupply following nitrate withdrawal, leading to enhanced root-tissue ABA accumulation, and that this enhancement, in turn, affects the expression of root-type NRT2/NAR genes. TaANR1 is shown to regulate nitrate-mediated ABA accumulation by directly activating TaBG1, while TaWabi5 is involved in ABA-mediated NO(3)(−) induction of NRT2/NAR genes. Building on previous evidence establishing ABA involvement in the developmental response to high-nitrate stress, our study suggests that ABA also contributes to the optimization of nitrate uptake by regulating the expression of NRT2/NAR genes under limited nitrate supply, offering a new target for improvement of nitrate absorption in crops.
- Published
- 2020
18. The Arabidopsis AMOT1/EIN3 gene plays an important role in the amelioration of ammonium toxicity
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Meng Wang, Herbert J. Kronzucker, Lin Zhang, Guangjie Li, Dong-Wei Di, and Weiming Shi
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inorganic chemicals ,0106 biological sciences ,0301 basic medicine ,Ethylene ,Physiology ,H2O2 ,Mutant ,Arabidopsis ,Ammonium stress ,Plant Science ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,AMOT1/EIN3 ,Auxin ,Gene Expression Regulation, Plant ,Ammonium Compounds ,Ammonium ,chemistry.chemical_classification ,amot1 mutant ,biology ,Chemistry ,Arabidopsis Proteins ,Wild type ,food and beverages ,biology.organism_classification ,Plants, Genetically Modified ,Research Papers ,Cell biology ,DNA-Binding Proteins ,030104 developmental biology ,Plant—Environment Interactions ,Toxicity ,Shoot ,Mutation ,peroxidases ,010606 plant biology & botany ,Transcription Factors - Abstract
We identified a novel Arabidopsis ammonium tolerance 1 (amot1) mutant and reveal that blocking of ethylene signaling reduces tissue H2O2 accumulation and enhances seedling tolerance to ammonium stress., Ammonium (NH4+) toxicity inhibits shoot growth in Arabidopsis, but the underlying mechanisms remain poorly characterized. Here, we show that a novel Arabidopsis mutant, ammonium tolerance 1 (amot1), exhibits enhanced shoot growth tolerance to NH4+. Molecular cloning revealed that amot1 is a new allele of EIN3, a key regulator of ethylene responses. The amot1 mutant and the allelic ein3-1 mutants show greater NH4+ tolerance than the wild type. Moreover, transgenic plants overexpressing EIN3 (EIN3ox) are more sensitive to NH4+ toxicity The ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) increases shoot sensitivity to NH4+, whereas the ethylene perception inhibitor Ag+ decreases sensitivity. NH4+ induces ACC and ethylene accumulation. Furthermore, ethylene-insensitive mutants such as etr1-3 and ein3eil1 display enhanced NH4+ tolerance. In contrast, the ethylene overproduction mutant eto1-1 exhibits decreased ammonium tolerance. AMOT1/EIN3 positively regulates shoot ROS accumulation, leading to oxidative stress under NH4+ stress, a trait that may be related to increased expression of peroxidase-encoding genes. These findings demonstrate the role of AMOT1/EIN3 in NH4+ tolerance and confirm the strong link between NH4+ toxicity symptoms and the accumulation of hydrogen peroxide.
- Published
- 2018
19. Analysis the role of arabidopsis CKRC6/ASA1 in auxin and cytokinin biosynthesis
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Pan Luo, Lei Wu, Xue Sun, Li Zhang, Guang-Qin Guo, Shaodong Wei, Dong-Wei Di, Tian-Zi Zhang, and Chen-Wei An
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0106 biological sciences ,0301 basic medicine ,chemistry.chemical_classification ,biology ,fungi ,Mutant ,Wild type ,Tryptophan ,food and beverages ,Plant Science ,biology.organism_classification ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Biosynthesis ,Biochemistry ,Auxin ,Arabidopsis ,Cytokinin ,biology.protein ,heterocyclic compounds ,Anthranilate synthase ,010606 plant biology & botany - Abstract
The crosstalk between auxin and cytokinin (CK) is important for plant growth and development, although the underlying molecular mechanisms remain unclear. Here, we describe the isolation and characterization of a mutant of Arabidopsis Cytokinin-induced Root Curling 6 (CKRC6), an allele of ANTHRANILATE SYNTHASE ALPHA SUBUNIT 1 (ASA1) that encodes the a-subunit of AS in tryptophan (Trp) biosynthesis. The ckrc6 mutant exhibits root gravitropic defects and insensitivity to both CK and the ethylene precursor 1-aminocyclopropane-1-carboxylicacid (ACC) in primary root growth. These defects can be rescued by exogenous indole-3-acetic acid (IAA) or tryptophan (Trp) supplementation. Furthermore, our results suggest that the ckrc6 mutant has decreased IAA content, differential expression patterns of auxin biosynthesis genes and CK biosynthesis isopentenyl transferase (IPT) genes in comparison to wild type. Collectively, our study shows that auxin controls CK biosynthesis based on that CK sensitivity is altered in most auxin-resistant mutants and that CKs promote auxin biosynthesis but inhibit auxin transport and response. Our results also suggest that CKRC6/ASA1 may be located at an intersection of auxin, CK and ethylene metabolism and/or signaling.
- Published
- 2016
20. Characterization and comparison of nitrate fluxes in Tamarix ramosissima and cotton roots under simulated drought conditions
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Lin Zhang, Guangjie Li, Gangqiang Dong, Meng Wang, Dong-Wei Di, Herbert J. Kronzucker, and Weiming Shi
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inorganic chemicals ,0106 biological sciences ,0301 basic medicine ,Physiology ,Nitrogen ,Drought tolerance ,Root system ,Plant Science ,Gossypium ,01 natural sciences ,Acclimatization ,Plant Roots ,03 medical and health sciences ,Soil ,Stress, Physiological ,Tamaricaceae ,Water-use efficiency ,Nitrates ,biology ,Chemistry ,Tamarix ,food and beverages ,Biological Transport ,Cistanche tubulosa ,biology.organism_classification ,Droughts ,030104 developmental biology ,Agronomy ,010606 plant biology & botany - Abstract
Tamarix ramosissima Ledeb., a major host plant for the parasitic angiosperm Cistanche tubulosa, and known for its unique drought tolerance, has significant ecological and economic benefits. However, the mechanisms of nitrogen acquisition by the T. ramosissima root system under drought have remained uncharacterized. Here, uptake of nitrate (NO3-) in various regions of the root system was measured in T. ramosissima using Non-invasive Micro-test Technology at the cellular level, and using a 15NO3--enrichment technique at the whole-root level. These results were compared with responses in the model system cotton (Gossypium hirsutum L.). Tamarix ramosissima had lower net NO3- influx and a significantly lower Km (the apparent Michalis-Menten constant; 8.5 μM) for NO3- uptake than cotton under normal conditions. Upon simulated drought conditions, using polyethylene glycol (PEG), NO3- flux in cotton switched from net influx to net efflux, with a substantive peak in the white zone (WZ) of the root. There were no significant NO3- influx signals observed in the WZ of T. ramosissima under control conditions, whereas PEG treatment significantly enhanced NO3- influx in the WZ of T. ramosissima. The effect of PEG application on NO3- fluxes was highly localized, and the increase in net NO3- influx in response to PEG stimulation was also found in C. tubulosa-inoculated T. ramosissima. Consistently, root nitrogen (N) content and root biomass were higher in T. ramosissima than in cotton under PEG treatment. Our study provides insights into NO3- uptake and the influence of C. tubulosa inoculation in T. ramosissima roots during acclimation to PEG-induced drought stress and provides guidelines for silvicultural practice and for breeding of T. ramosissima under coupled conditions of soil drought and N deficiency.
- Published
- 2018
21. Excess iron stress reduces root tip zone growth through nitric oxide-mediated repression of potassium homeostasis in Arabidopsis
- Author
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Lin Zhang, Li Sun, Herbert J. Kronzucker, Meng Wang, Guangjie Li, Dong-Wei Di, and Weiming Shi
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0106 biological sciences ,0301 basic medicine ,Programmed cell death ,Ethylene ,Physiology ,Potassium ,Iron ,Mutant ,Arabidopsis ,chemistry.chemical_element ,Plant Science ,Nitric Oxide ,01 natural sciences ,Plant Roots ,Nitric oxide ,03 medical and health sciences ,chemistry.chemical_compound ,Stress, Physiological ,Homeostasis ,Viability assay ,Pyridoxal Kinase ,biology ,Cell Death ,Arabidopsis Proteins ,Ethylenes ,biology.organism_classification ,Plants, Genetically Modified ,030104 developmental biology ,chemistry ,Biophysics ,010606 plant biology & botany - Abstract
The root tip zone is regarded as the principal action site for iron (Fe) toxicity and is more sensitive than other root zones, but the mechanism underpinning this remains largely unknown. We explored the mechanism underpinning the higher sensitivity at the Arabidopsis root tip and elucidated the role of nitric oxide (NO) using NO-related mutants and pharmacological methods. Higher Fe sensitivity of the root tip is associated with reduced potassium (K+ ) retention. NO in root tips is increased significantly above levels elsewhere in the root and is involved in the arrest of primary root tip zone growth under excess Fe, at least in part related to NO-induced K+ loss via SNO1 (sensitive to nitric oxide 1)/SOS4 (salt overly sensitive 4) and reduced root tip zone cell viability. Moreover, ethylene can antagonize excess Fe-inhibited root growth and K+ efflux, in part by the control of root tip NO levels. We conclude that excess Fe attenuates root growth by effecting an increase in root tip zone NO, and that this attenuation is related to NO-mediated alterations in K+ homeostasis, partly via SNO1/SOS4.
- Published
- 2018
22. The biosynthesis of auxin: how many paths truly lead to IAA?
- Author
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Guang-Qin Guo, Pan Luo, Chen-Wei An, Dong-Wei Di, and Caiguo Zhang
- Subjects
0106 biological sciences ,0301 basic medicine ,Tryptamine ,Physiology ,Mutant ,Plant Science ,Biology ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Biosynthesis ,Auxin ,Auxin biosynthesis ,heterocyclic compounds ,Gene ,chemistry.chemical_classification ,fungi ,food and beverages ,Plant physiology ,biology.organism_classification ,030104 developmental biology ,chemistry ,Biochemistry ,Agronomy and Crop Science ,Bacteria ,010606 plant biology & botany - Abstract
The plant auxin indole-3-acetic acid (IAA) plays critical roles in plant growth and development. There are two main strategies proposed for plant synthesis of IAA: the Trp-dependent (TD) and the Trp-independent (TI) pathways. Four TD pathways, namely the indole-3-acetamide pathway, the indole-3-pyruvic acid pathway, the tryptamine pathway and the indole-3-acetaldoxime pathway, have been postulated, identified and extensively studied. On the other hand, neither genes nor mutants involved in the TI pathway have been identified to date. Interestingly, some bacteria have auxin synthesis pathways that are similar to those in plants, indicating conserved biosynthetic mechanisms. Over the past few years, genetic, biochemical and molecular studies have greatly advanced our understanding of auxin biosynthesis. This review both summarizes recent advances in genetic and molecular knowledge and addresses the unsolved questions regarding auxin biosynthesis pathways in plants.
- Published
- 2015
23. Involvement of secondary messengers and small organic molecules in auxin perception and signaling
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Caiguo Zhang, Guang-Qin Guo, and Dong-Wei Di
- Subjects
Receptors, Cell Surface ,Plant Science ,Biology ,Nitric Oxide ,Nitric oxide ,Diglycerides ,chemistry.chemical_compound ,Plant Growth Regulators ,Auxin ,heterocyclic compounds ,Receptor ,Plant Proteins ,Diacylglycerol kinase ,chemistry.chemical_classification ,Reactive oxygen species ,Indoleacetic Acids ,Arabidopsis Proteins ,F-Box Proteins ,fungi ,food and beverages ,General Medicine ,Plants ,Transport inhibitor ,E2F Transcription Factors ,Biochemistry ,chemistry ,Second messenger system ,Calcium ,Signal transduction ,Reactive Oxygen Species ,Agronomy and Crop Science ,Signal Transduction - Abstract
Auxin is a major phytohormone involved in most aspects of plant growth and development. Generally, auxin is perceived by three distinct receptors: TRANSPORT INHIBITOR RESISTANT1-Auxin/INDOLE ACETIC ACID, S-Phase Kinase-Associated Protein 2A and AUXIN-BINDING PROTEIN1. The auxin perception is regulated by a variety of secondary messenger molecules, including nitric oxide, reactive oxygen species, calcium, cyclic GMP, cyclic AMP, inositol triphosphate, diacylglycerol and by physiological pH. In addition, some small organic molecules, including inositol hexakisphosphate, yokonolide B, p-chlorophenoxyisobutyric acid, toyocamycin and terfestatin A, are involved in auxin signaling. In this review, we summarize and discuss the recent progress in understanding the functions of these secondary messengers and small organic molecules, which are now thoroughly demonstrated to be pervasive and important in auxin perception and signal transduction.
- Published
- 2015
24. Frequent problems and their resolutions by using thermal asymmetric interlaced PCR (TAIL-PCR) to clone genes inArabidopsisT-DNA tagged mutants
- Author
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Pan Luo, Lei Wu, Dan Zhang, Bin Song, Guang-Qin Guo, and Dong-Wei Di
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Genetics ,Cloning ,Articles ,Agriculture and Environmental Biotechnology ,high-throughput sequencing ,Mutagenesis (molecular biology technique) ,Biology ,DNA sequencing ,law.invention ,Insertional mutagenesis ,chemistry.chemical_compound ,T-DNA tagged mutants ,complex T-DNA insertion ,chemistry ,TAIL-PCR ,law ,Functional genomics ,Gene ,Polymerase chain reaction ,DNA ,Biotechnology - Abstract
T-DNA insertional mutagenesis is a powerful tool in Arabidopsis functional genomics research. Previous studies have developed thermal asymmetric interlaced polymerase chain reaction (TAIL-PCR) as an efficient strategy in isolation of DNA sequences adjacent to known sequences in T-DNA tagged mutants. However, a number of problems are encountered when attempts are made to clone flanking sequences in T-DNA tagged mutants. Therefore, it is necessary to improve the efficiency of cloning mutagenesis. Here, we present the most frequent problems and provide an improved method to increase TAIL-PCR efficiency. Even then, it is not always possible to successfully obtain flanking sequences; in such cases, we recommend using high-throughput sequencing to determine the mutations.
- Published
- 2015
25. Spatio-temporal dynamics in global rice gene expression (Oryza sativa L.) in response to high ammonium stress
- Author
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Li Sun, Guangjie Li, Dong-Wei Di, Herbert J. Kronzucker, and Weiming Shi
- Subjects
0106 biological sciences ,0301 basic medicine ,Time Factors ,Physiology ,Acclimatization ,Plant Science ,01 natural sciences ,Plant Roots ,chemistry.chemical_compound ,Plant Growth Regulators ,Gene Expression Regulation, Plant ,Ammonium Compounds ,Amino Acids ,Abscisic acid ,Plant Proteins ,Regulation of gene expression ,Phenylpropanoid ,biology ,food and beverages ,Up-Regulation ,Phenotype ,Biochemistry ,RNA, Plant ,Shoot ,Mitogen-Activated Protein Kinases ,Plant Shoots ,Signal Transduction ,inorganic chemicals ,Nitrogen ,Oryza ,Genes, Plant ,03 medical and health sciences ,Stress, Physiological ,Proline ,Flavonoids ,Oryza sativa ,Sequence Analysis, RNA ,Gene Expression Profiling ,fungi ,Ethylenes ,biology.organism_classification ,030104 developmental biology ,Flavonoid biosynthesis ,Gene Ontology ,chemistry ,Transcriptome ,Agronomy and Crop Science ,010606 plant biology & botany ,Abscisic Acid - Abstract
Ammonium (NH4+) is the predominant nitrogen (N) source in many natural and agricultural ecosystems, including flooded rice fields. While rice is known as an NH4+-tolerant species, it nevertheless suffers NH4+ toxicity at elevated soil concentrations. NH4+ excess rapidly leads to the disturbance of various physiological processes that ultimately inhibit shoot and root growth. However, the global transcriptomic response to NH4+ stress in rice has not been examined. In this study, we mapped the spatio-temporal specificity of gene expression profiles in rice under excess NH4+ and the changes in gene expression in root and shoot at various time points by RNA-Seq (Quantification) using Illumina HiSeqTM 2000. By comparative analysis, 307 and 675 genes were found to be up-regulated after 4h and 12h of NH4+ exposure in the root, respectively. In the shoot, 167 genes were up-regulated at 4h, compared with 320 at 12h. According to KEGG analysis, up-regulated DEGs mainly participate in phenylpropanoid (such as flavonoid) and amino acid (such as proline, cysteine, and methionine) metabolism, which is believed to improve NH4+ stress tolerance through adjustment of energy metabolism in the shoot, while defense and signaling pathways, guiding whole-plant acclimation, play the leading role in the root. We furthermore critically assessed the roles of key phytohormones, and found abscisic acid (ABA) and ethylene (ET) to be the major regulatory molecules responding to excess NH4+ and activating the MAPK (mitogen-activated protein kinase) signal-transduction pathway. Moreover, we found up-regulated hormone-associated genes are involved in regulating flavonoid biosynthesis and are regulated by tissue flavonoid accumulation.
- Published
- 2017
26. Functional roles of Arabidopsis CKRC2/YUCCA8 gene and the involvement of PIF4 in the regulation of auxin biosynthesis by cytokinin
- Author
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Verena Kriechbaumer, Pan Luo, Huanhuan Gao, Chen-Wei An, Li Zhang, Tian-Zi Zhang, Lei Wu, Guang-Qin Guo, and Dong-Wei Di
- Subjects
0106 biological sciences ,0301 basic medicine ,Cytokinins ,Arabidopsis ,Plant Roots ,01 natural sciences ,Article ,Mixed Function Oxygenases ,03 medical and health sciences ,chemistry.chemical_compound ,Downregulation and upregulation ,Gene Expression Regulation, Plant ,Auxin ,Basic Helix-Loop-Helix Transcription Factors ,heterocyclic compounds ,Gene ,chemistry.chemical_classification ,Multidisciplinary ,Indoleacetic Acids ,biology ,Arabidopsis Proteins ,fungi ,food and beverages ,biology.organism_classification ,Hedgehog signaling pathway ,030104 developmental biology ,Enzyme ,Biochemistry ,chemistry ,Cytokinin ,Signal transduction ,Signal Transduction ,010606 plant biology & botany - Abstract
Auxin and cytokinin (CK) are both important hormones involved in many aspects of plant growth and development. However, the details of auxin biosynthesis and the interaction between auxin and CK are still unclear. Isolation and characterization of an auxin deficient mutant cytokinin induced root curling 2 (ckrc2) in this work reveal that CKRC2 encodes a previously identified member of YUCCA (YUC) flavin monooxygenase-like proteins (YUC8). Our results show that, like other YUCs, CKRC2/YUC8 is a rate-limiting enzyme for catalyzing the conversion of indole-3-pyruvic acid (IPyA) to indole-3-acetic acid (IAA), acting downstream of CKRC1/TAA1 in the IPyA pathway. Here we show that the transcription of both CKRC1/TAA and CKRC2/YUC8 can be induced by CK and that the phytochrome-interacting factor 4 (PIF4) is required for this upregulation. Transcription of PIF4 itself is induced by CK via the AHKs-ARR1/12 signalling pathway. These results indicate that PIF4 plays an essential role in mediating the regulatory effect of CK on the transcriptions of CKRC1 and CKRC2 genes in the IPyA pathway of auxin biosynthesis.
- Published
- 2016
- Full Text
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27. Forward genetic screen for auxin-deficient mutants by cytokinin
- Author
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Pan Luo, Li Wang, Tian-Zi Zhang, Ondřej Novák, Miroslav Strnad, Ming Wang, Guang-Qin Guo, Li Zhang, Dong-Wei Di, Shaodong Wei, Petra Amakorová, Lei Wu, and Cheng-Kai Lu
- Subjects
Cytokinins ,Mutant ,Arabidopsis ,Biology ,medicine.disease_cause ,Plant Roots ,Article ,chemistry.chemical_compound ,Plant Growth Regulators ,Auxin ,Tryptophan Transaminase ,medicine ,heterocyclic compounds ,Gene ,chemistry.chemical_classification ,Genetics ,Mutation ,Multidisciplinary ,Indoleacetic Acids ,Arabidopsis Proteins ,fungi ,food and beverages ,Biological Transport ,biology.organism_classification ,Complementation ,Phenotype ,chemistry ,Seedlings ,Cytokinin ,Genetic screen ,Signal Transduction - Abstract
Identification of mutants with impairments in auxin biosynthesis and dynamics by forward genetic screening is hindered by the complexity, redundancy and necessity of the pathways involved. Furthermore, although a few auxin-deficient mutants have been recently identified by screening for altered responses to shade, ethylene, N-1-naphthylphthalamic acid (NPA) or cytokinin (CK), there is still a lack of robust markers for systematically isolating such mutants. We hypothesized that a potentially suitable phenotypic marker is root curling induced by CK, as observed in the auxin biosynthesis mutant CK-induced root curling 1 / tryptophan aminotransferase of Arabidopsis 1 (ckrc1/taa1). Phenotypic observations, genetic analyses and biochemical complementation tests of Arabidopsis seedlings displaying the trait in large-scale genetic screens showed that it can facilitate isolation of mutants with perturbations in auxin biosynthesis, transport and signaling. However, unlike transport/signaling mutants, the curled (or wavy) root phenotypes of auxin-deficient mutants were significantly induced by CKs and could be rescued by exogenous auxins. Mutants allelic to several known auxin biosynthesis mutants were re-isolated, but several new classes of auxin-deficient mutants were also isolated. The findings show that CK-induced root curling provides an effective marker for discovering genes involved in auxin biosynthesis or homeostasis.
- Published
- 2015
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