1
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Shen Y, Wang G, Ran J, Li Y, Wang H, Ding Q, Li Y, Hou X. Regulation of the trade-off between cold stress and growth by glutathione S-transferase phi class 10 (BcGSTF10) in non-heading Chinese cabbage. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1887-1902. [PMID: 38079376 DOI: 10.1093/jxb/erad494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 12/10/2023] [Indexed: 03/28/2024]
Abstract
Cold stress is a serious threat to global crop production and food security, but plant cold resistance is accompanied by reductions in growth and yield. In this study, we determined that the novel gene BcGSTF10 in non-heading Chinese cabbage [NHCC; Brassica campestris (syn. Brassica rapa) ssp. chinensis] is implicated in resistance to cold stress. Biochemical and genetic analyses demonstrated that BcGSTF10 interacts with BcICE1 to induce C-REPEAT BINDING FACTOR (CBF) genes that enhance freezing tolerance in NHCC and in Arabidopsis. However, BcCBF2 represses BcGSTF10 and the latter promotes growth in NHCC and Arabidopsis. This dual function of BcGSTF10 indicates its pivotal role in balancing cold stress and growth, and this important understanding has the potential to inform the future development of strategies to breed crops that are both climate-resilient and high-yielding.
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Affiliation(s)
- Yunlou Shen
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
| | - Guangpeng Wang
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiajun Ran
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
| | - Yiran Li
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
| | - Huiyu Wang
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
| | - Qiang Ding
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
| | - Ying Li
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
- Nanjing Suman Plasma Engineering Research Institute Co., Ltd., Nanjing 211162, China
| | - Xilin Hou
- National Key Laboratory of Crop Genetics & Germplasm Innovation and Utilization, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Ministry of Agriculture and Rural Affairs of China, Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Ministry of Education of China, Nanjing Agricultural University, Nanjing 210095, China
- Nanjing Suman Plasma Engineering Research Institute Co., Ltd., Nanjing 211162, China
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Ouyang Q, Zhang Y, Yang X, Yang C, Hou D, Liu H, Xu H. Overexpression of OsPIN9 Impairs Chilling Tolerance via Disturbing ROS Homeostasis in Rice. PLANTS (BASEL, SWITZERLAND) 2023; 12:2809. [PMID: 37570963 PMCID: PMC10421329 DOI: 10.3390/plants12152809] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/23/2023] [Accepted: 07/26/2023] [Indexed: 08/13/2023]
Abstract
The auxin efflux transporter PIN-FORMED (PIN) family is one of the major protein families that facilitates polar auxin transport in plants. Here, we report that overexpression of OsPIN9 leads to altered plant architecture and chilling tolerance in rice. The expression profile analysis indicated that OsPIN9 was gradually suppressed by chilling stress. The shoot height and adventitious root number of OsPIN9-overexpressing (OE) plants were significantly reduced at the seedling stage. The roots of OE plants were more tolerant to N-1-naphthylphthalamic acid (NPA) treatment than WT plants, indicating the disturbance of auxin homeostasis in OE lines. The chilling tolerance assay showed that the survival rate of OE plants was markedly lower than that of wild-type (WT) plants. Consistently, more dead cells, increased electrolyte leakage, and increased malondialdehyde (MDA) content were observed in OE plants compared to those in WT plants under chilling conditions. Notably, OE plants accumulated more hydrogen peroxide (H2O2) and less superoxide anion radicals (O2-) than WT plants under chilling conditions. In contrast, catalase (CAT) and superoxide dismutase (SOD) activities in OE lines decreased significantly compared to those in WT plants at the early chilling stage, implying that the impaired chilling tolerance of transgenic plants is probably attributed to the sharp induction of H2O2 and the delayed induction of antioxidant enzyme activities at this stage. In addition, several OsRboh genes, which play a crucial role in ROS production under abiotic stress, showed an obvious increase after chilling stress in OE plants compared to that in WT plants, which probably at least in part contributes to the production of ROS under chilling stress in OE plants. Together, our results reveal that OsPIN9 plays a vital role in regulating plant architecture and, more importantly, is involved in regulating rice chilling tolerance by influencing auxin and ROS homeostasis.
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Affiliation(s)
| | | | | | | | | | | | - Huawei Xu
- College of Agriculture, Henan University of Science and Technology, Luoyang 471000, China; (Q.O.); (Y.Z.); (X.Y.); (C.Y.); (D.H.); (H.L.)
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Gou H, Nai G, Lu S, Ma W, Chen B, Mao J. Genome-wide identification and expression analysis of PIN gene family under phytohormone and abiotic stresses in Vitis Vinifera L. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:1905-1919. [PMID: 36484025 PMCID: PMC9723067 DOI: 10.1007/s12298-022-01239-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 09/13/2022] [Accepted: 10/12/2022] [Indexed: 06/17/2023]
Abstract
The auxin efflux transport proteins PIN-formed (PIN) has wide adaptability to hormone and abiotic stress, but the response mechanism of PINs in grape remains unclear. In this study, 12 members of VvPINs were identified and distributed on 8 chromosomes. The PIN genes of five species were divided into two subgroups, and the similarity of exons/introns and motifs of VvPIN genes were found in the same subgroup. Meanwhile, according to the examination of conserved motifs, the motif 3 included the conserved structure NPNTY. The promoter region of VvPIN gene family contained various cis-acting elements, which were related to light, abiotic stress, and hormones which are essential for growth and development. Additionally, VvPIN1, VvPIN9, and VvPIN11 proteins simultaneously interacted with the ARF, ABC, PINOID, GBF1, and VIT_08s0007g09010. The results of qRT-PCR revealed that the majority of the VvPINs were highly induced by NAA, GA3, ABA, MeJA, SA, NaCl, low-temperature (4 ℃), and PEG treatments, and the results were consistent with the prediction of the cis-acting elements. Moreover, the expression profile and quantitative real-time PCR (qRT-PCR) demonstrated that VvPIN genes were expressed in roots, stems, and leaves. The subcellular localization of VvPIN1 in Nicotiana benthamiana revealed that VvPIN1 was localized at the plasma membrane. Collectively, this study revealed that PIN genes could respond to various abiotic stresses, and provided a framework for regulating the expression of PIN genes to enhance the resistance of the grape. Supplementary Information The online version contains supplementary material available at 10.1007/s12298-022-01239-8.
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Affiliation(s)
- Huimin Gou
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070 Gansu Province People’s Republic of China
| | - Guojie Nai
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070 Gansu Province People’s Republic of China
| | - Shixiong Lu
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070 Gansu Province People’s Republic of China
| | - Weifeng Ma
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070 Gansu Province People’s Republic of China
| | - Baihong Chen
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070 Gansu Province People’s Republic of China
| | - Juan Mao
- College of Horticulture, Gansu Agricultural University, Lanzhou, 730070 Gansu Province People’s Republic of China
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4
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Xu H, Yang X, Zhang Y, Wang H, Wu S, Zhang Z, Ahammed GJ, Zhao C, Liu H. CRISPR/Cas9-mediated mutation in auxin efflux carrier OsPIN9 confers chilling tolerance by modulating reactive oxygen species homeostasis in rice. FRONTIERS IN PLANT SCIENCE 2022; 13:967031. [PMID: 35979077 PMCID: PMC9376474 DOI: 10.3389/fpls.2022.967031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Phytohormone auxin plays a vital role in plant development and responses to environmental stresses. The spatial and temporal distribution of auxin mainly relies on the polar distribution of the PIN-FORMED (PIN) auxin efflux carriers. In this study, we dissected the functions of OsPIN9, a monocot-specific auxin efflux carrier gene, in modulating chilling tolerance in rice. The results showed that OsPIN9 expression was dramatically and rapidly suppressed by chilling stress (4°C) in rice seedlings. The homozygous ospin9 mutants were generated by CRISPR/Cas9 technology and employed for further research. ospin9 mutant roots and shoots were less sensitive to 1-naphthaleneacetic acid (NAA) and N-1-naphthylphthalamic acid (NPA), indicating the disturbance of auxin homeostasis in the ospin9 mutants. The chilling tolerance assay showed that ospin9 mutants were more tolerant to chilling stress than wild-type (WT) plants, as evidenced by increased survival rate, decreased membrane permeability, and reduced lipid peroxidation. However, the expression of well-known C-REPEAT BINDING FACTOR (CBF)/DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 1 (DREB)-dependent transcriptional regulatory pathway and Ca2+ signaling genes was significantly induced only under normal conditions, implying that defense responses in ospin9 mutants have probably been triggered in advance under normal conditions. Histochemical staining of reactive oxygen species (ROS) by 3'3-diaminobenzidine (DAB) and nitroblue tetrazolium (NBT) showed that ospin9 mutants accumulated more ROS than WT at the early stage of chilling stress, while less ROS was observed at the later stage of chilling treatment in ospin9 mutants. Consistently, antioxidant enzyme activity, including catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD), improved significantly during the early chilling treatments, while was kept similar to WT at the later stage of chilling treatment, implying that the enhanced chilling tolerance of ospin9 mutants is mainly attributed to the earlier induction of ROS and the improved ROS scavenging ability at the subsequent stages of chilling treatment. In summary, our results strongly suggest that the OsPIN9 gene regulates chilling tolerance by modulating ROS homeostasis in rice.
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Affiliation(s)
- Huawei Xu
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Xiaoyi Yang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Yanwen Zhang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Huihui Wang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Shiyang Wu
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Zhuoyan Zhang
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Golam Jalal Ahammed
- College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, China
| | - Chunzhao Zhao
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Hao Liu
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
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Ashraf MA, Rahman A. Cellular Protein Trafficking: A New Player in Low-Temperature Response Pathway. PLANTS (BASEL, SWITZERLAND) 2022; 11:933. [PMID: 35406913 PMCID: PMC9003145 DOI: 10.3390/plants11070933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/26/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
Unlike animals, plants are unable to escape unfavorable conditions, such as extremities of temperature. Among abiotic variables, the temperature is notableas it affects plants from the molecular to the organismal level. Because of global warming, understanding temperature effects on plants is salient today and should be focused not only on rising temperature but also greater variability in temperature that is now besetting the world's natural and agricultural ecosystems. Among the temperature stresses, low-temperature stress is one of the major stresses that limits crop productivity worldwide. Over the years, although substantial progress has been made in understanding low-temperature response mechanisms in plants, the research is more focused on aerial parts of the plants rather than on the root or whole plant, and more efforts have been made in identifying and testing the major regulators of this pathway preferably in the model organism rather than in crop plants. For the low-temperature stress response mechanism, ICE-CBF regulatory pathway turned out to be the solely established pathway, and historically most of the low-temperature research is focused on this single pathway instead of exploring other alternative regulators. In this review, we tried to take an in-depth look at our current understanding of low temperature-mediated plant growth response mechanism and present the recent advancement in cell biological studies that have opened a new horizon for finding promising and potential alternative regulators of the cold stress response pathway.
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Affiliation(s)
- M Arif Ashraf
- Biology Department, University of Massachusetts, Amherst, MA 01003, USA
| | - Abidur Rahman
- The United Graduate School of Agricultural Sciences, Iwate University, Morioka 020-8550, Japan
- Department of Plant Biosciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan
- Department of Plant Sciences, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
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6
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Wang X, Song Q, Liu Y, Brestic M, Yang X. The network centered on ICEs play roles in plant cold tolerance, growth and development. PLANTA 2022; 255:81. [PMID: 35249133 DOI: 10.1007/s00425-022-03858-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
ICEs are key transcription factors in response to cold in plant, they also balance plant growth and stress tolerance. Thus, we systematize the information about ICEs published to date. Low temperature is an important factor affecting plant growth and development. Exposing to cold condition results in a suit of effects on plants including reduction of plant growth and reproduction, and decrease in crop yield and quality. Plants have evolved a series of strategies to deal with cold stress such as reprogramming of the expression of genes and transcription factors. ICEs (Inducer of CBF Expression), as transcription factors regulating CBFs (C-repeat binding factor), play key roles in balancing plant growth and stress tolerance. Studies on ICEs focused on the function of ICEs on cold tolerance, growth and development; post-translational modifications of ICEs and crosstalk between the ICEs and phytohormones. In this review, we focus on systematizing the information published to date. We summarized the main advances of the functions of ICEs on the cold tolerance, growth and development. And we also elaborated the regulation of ICEs protein stability including phosphorylation, ubiquitination and SUMOylation of ICE. Finally, we described the function of ICEs in the crosstalk among different phytohormone signaling pathway and cold stress. This review provides perspectives for ongoing research about cold tolerance, growth and development in plant.
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Affiliation(s)
- Xipan Wang
- College of Life Science, State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong Agricultural University, Taian, 271018, China
| | - Qiping Song
- College of Life Science, State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong Agricultural University, Taian, 271018, China
| | - Yang Liu
- College of Life Science, State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong Agricultural University, Taian, 271018, China
| | - Marian Brestic
- Department of Plant Physiology, Slovak University of Agriculture, A. Hlinku 2, Nitra, 94976, Slovak Republic
| | - Xinghong Yang
- College of Life Science, State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, Shandong Agricultural University, Taian, 271018, China.
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Aslam M, Sugita K, Qin Y, Rahman A. Aux/IAA14 Regulates microRNA-Mediated Cold Stress Response in Arabidopsis Roots. Int J Mol Sci 2020; 21:E8441. [PMID: 33182739 PMCID: PMC7697755 DOI: 10.3390/ijms21228441] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/04/2020] [Accepted: 11/04/2020] [Indexed: 12/16/2022] Open
Abstract
The phytohormone auxin and microRNA-mediated regulation of gene expressions are key regulators of plant growth and development at both optimal and under low-temperature stress conditions. However, the mechanistic link between microRNA and auxin in regulating plant cold stress response remains elusive. To better understand the role of microRNA (miR) in the crosstalk between auxin and cold stress responses, we took advantage of the mutants of Arabidopsis thaliana with altered response to auxin transport and signal. Screening of the mutants for root growth recovery after cold stress at 4 °C revealed that the auxin signaling mutant, solitary root 1 (slr1; mutation in Aux/IAA14), shows a hypersensitive response to cold stress. Genome-wide expression analysis of miRs in the wild-type and slr1 mutant roots using next-generation sequencing revealed 180 known and 71 novel cold-responsive microRNAs. Cold stress also increased the abundance of 26-31 nt small RNA population in slr1 compared with wild type. Comparative analysis of microRNA expression shows significant differential expression of 13 known and 7 novel miRs in slr1 at 4 °C compared with wild type. Target gene expression analysis of the members from one potential candidate miR, miR169, revealed the possible involvement of miR169/NF-YA module in the Aux/IAA14-mediated cold stress response. Taken together, these results indicate that SLR/IAA14, a transcriptional repressor of auxin signaling, plays a crucial role in integrating miRs in auxin and cold responses.
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Affiliation(s)
- Mohammad Aslam
- Department of Plant Bio Sciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan; (M.A.); (K.S.)
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Lab of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning 530004, China;
- Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Center for Genomics and Biotechnology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Kenji Sugita
- Department of Plant Bio Sciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan; (M.A.); (K.S.)
| | - Yuan Qin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi Key Lab of Sugarcane Biology, College of Agriculture, Guangxi University, Nanning 530004, China;
- Key Laboratory of Genetics, Breeding and Multiple Utilization of Crops, Ministry of Education, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Center for Genomics and Biotechnology, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Abidur Rahman
- Department of Plant Bio Sciences, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan; (M.A.); (K.S.)
- United Graduate School of Agricultural Sciences, Iwate University, Morioka 020-8550, Japan
- Agri-Innovation Center, Faculty of Agriculture, Iwate University, Morioka 020-8550, Japan
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Khan TA, Fariduddin Q, Yusuf M. Low-temperature stress: is phytohormones application a remedy? ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:21574-21590. [PMID: 28831664 DOI: 10.1007/s11356-017-9948-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 08/11/2017] [Indexed: 05/11/2023]
Abstract
Among the various abiotic stresses, low temperature is one of the major environmental constraints that limit the plant development and crop productivity. Plants are able to adapt to low-temperature stress through the changes in membrane composition and activation of reactive oxygen scavenging systems. The genetic pathway induced due to temperature downshift is based on C-repeat-binding factors (CBF) which activate promoters through the C-repeat (CRT) cis-element. Calcium entry is a major signalling event occurring immediately after a downshift in temperature. The increase in the level of cytosolic calcium activates many enzymes, such as phospholipases and calcium dependent-protein kinases. MAP-kinase module has been shown to be involved in the cold response. Ultimately, the activation of these signalling pathways leads to changes in the transcriptome. Several phytohormones, such as abscisic acid, brassinosteroids, auxin, salicylic acid, gibberellic acid, cytokinins and jasmonic acid, have been shown to play key roles in regulating the plant development under low-temperature stress. These phytohormones modulate important events involved in tolerance to low-temperature stress in plants. Better understanding of these events and genes controlling these could open new strategies for improving tolerance mediated by phytohormones.
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Affiliation(s)
- Tanveer Alam Khan
- Plant Physiology and Biochemistry Section, Department of Botany, Aligarh Muslim University, Aligarh, 202002, India
| | - Qazi Fariduddin
- Plant Physiology and Biochemistry Section, Department of Botany, Aligarh Muslim University, Aligarh, 202002, India.
| | - Mohammad Yusuf
- Plant Physiology and Biochemistry Section, Department of Botany, Aligarh Muslim University, Aligarh, 202002, India
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Sharma KD, Nayyar H. Regulatory Networks in Pollen Development under Cold Stress. FRONTIERS IN PLANT SCIENCE 2016; 7:402. [PMID: 27066044 PMCID: PMC4814731 DOI: 10.3389/fpls.2016.00402] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 03/14/2016] [Indexed: 05/18/2023]
Abstract
Cold stress modifies anthers' metabolic pathways to induce pollen sterility. Cold-tolerant plants, unlike the susceptible ones, produce high proportion of viable pollen. Anthers in susceptible plants, when exposed to cold stress, increase abscisic acid (ABA) metabolism and reduce ABA catabolism. Increased ABA negatively regulates expression of tapetum cell wall bound invertase and monosaccharide transport genes resulting in distorted carbohydrate pool in anther. Cold-stress also reduces endogenous levels of the bioactive gibberellins (GAs), GA4 and GA7, in susceptible anthers by repression of the GA biosynthesis genes. Here, we discuss recent findings on mechanisms of cold susceptibility in anthers which determine pollen sterility. We also discuss differences in regulatory pathways between cold-stressed anthers of susceptible and tolerant plants that decide pollen sterility or viability.
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Affiliation(s)
- Kamal D. Sharma
- Department of Agricultural Biotechnology, Chaudhary Sarwan Kumar Himachal Pradesh Agricultural UniversityPalampur, India
| | - Harsh Nayyar
- Department of Botany, Panjab UniversityChandigarh, India
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Yoon DH, Lee SS, Park HJ, Lyu JI, Chong WS, Liu JR, Kim BG, Ahn JC, Cho HS. Overexpression of OsCYP19-4 increases tolerance to cold stress and enhances grain yield in rice (Oryza sativa). JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:69-82. [PMID: 26453745 PMCID: PMC4682425 DOI: 10.1093/jxb/erv421] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
AtCYP19-4 (also known as CYP5) was previously identified as interacting in vitro with GNOM, a member of a large family of ARF guanine nucleotide exchange factors that is required for proper polar localization of the auxin efflux carrier PIN1. The present study demonstrated that OsCYP19-4, a gene encoding a putative homologue of AtCYP19-4, was up-regulated by several stresses and showed over 10-fold up-regulation in response to cold. The study further demonstrated that the promoter of OsCYP19-4 was activated in response to cold stress. An OsCYP19-4-GFP fusion protein was targeted to the outside of the plasma membrane via the endoplasmic reticulum as determined using brefeldin A, a vesicle trafficking inhibitor. An in vitro assay with a synthetic substrate oligomer confirmed that OsCYP19-4 had peptidyl-prolyl cis-trans isomerase activity, as was previously reported for AtCYP19-4. Rice plants overexpressing OsCYP19-4 showed cold-resistance phenotypes with significantly increased tiller and spike numbers, and consequently enhanced grain weight, compared with wild-type plants. Based on these results, the authors suggest that OsCYP19-4 is required for developmental acclimation to environmental stresses, especially cold. Furthermore, the results point to the potential of manipulating OsCYP19-4 expression to enhance cold tolerance or to increase biomass.
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Affiliation(s)
- Dae Hwa Yoon
- Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea Department of Pharmacology, College of Medicine, Seonam University, Namwon 590-170, Korea
| | - Sang Sook Lee
- Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea
| | - Hyun Ji Park
- Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea
| | - Jae Il Lyu
- Department of New Biology, Daegu Gyeongbuk Institute of Science & Technology, Daegu 711-873, Korea
| | - Won Seog Chong
- Department of Pharmacology, College of Medicine, Seonam University, Namwon 590-170, Korea
| | - Jang Ryol Liu
- Department of New Biology, Daegu Gyeongbuk Institute of Science & Technology, Daegu 711-873, Korea
| | - Beom-Gi Kim
- Molecular Breeding Division, National Academy of Agricultural Science, RDA, Jeonju 560-500, Korea
| | - Jun Cheul Ahn
- Department of Pharmacology, College of Medicine, Seonam University, Namwon 590-170, Korea
| | - Hye Sun Cho
- Sustainable Bioresource Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea
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11
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Zhu J, Zhang KX, Wang WS, Gong W, Liu WC, Chen HG, Xu HH, Lu YT. Low temperature inhibits root growth by reducing auxin accumulation via ARR1/12. PLANT & CELL PHYSIOLOGY 2015; 56:727-36. [PMID: 25552473 DOI: 10.1093/pcp/pcu217] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 12/28/2014] [Indexed: 05/18/2023]
Abstract
Plants exhibit reduced root growth when exposed to low temperature; however, how low temperature modulates root growth remains to be understood. Our study demonstrated that low temperature reduces both meristem size and cell number, repressing the division potential of meristematic cells by reducing auxin accumulation, possibly through the repressed expression of PIN1/3/7 and auxin biosynthesis-related genes, although the experiments with exogenous auxin application also suggest the involvement of other factor(s). In addition, we verified that ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) and ARR12 are involved in low temperature-mediated inhibition of root growth by showing that the roots of arr1-3 arr12-1 seedlings were less sensitive than wild-type roots to low temperature, in terms of changes in root length and meristem cell number. Furthermore, low temperature reduced the levels of PIN1/3 transcripts and the auxin level to a lesser extent in arr1-3 arr12-1 roots than in wild-type roots, suggesting that cytokinin signaling is involved in the low-temperature-mediated reduction of auxin accumulation. Taken together, our data suggest that low temperature inhibits root growth by reducing auxin accumulation via ARR1/12.
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Affiliation(s)
- Jiang Zhu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Kun-Xiao Zhang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Wen-Shu Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Wen Gong
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Wen-Cheng Liu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Hong-Guo Chen
- College of Chemistry and Biology, Hubei University of Science and Technology, Xianning 437100, Hubei Province, China
| | - Heng-Hao Xu
- Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening, Huaihai Institute of Technology, Lianyungang 222005, China
| | - Ying-Tang Lu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
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Taniguchi M, Nakamura M, Tasaka M, Morita MT. Identification of gravitropic response indicator genes in Arabidopsis inflorescence stems. PLANT SIGNALING & BEHAVIOR 2014; 9:e29570. [PMID: 25763694 PMCID: PMC4203507 DOI: 10.4161/psb.29570] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Differential organ growth during gravitropic response is caused by differential accumulation of auxin, that is, relative higher auxin concentration in lower flanks than in upper flanks of responding organs. Auxin responsive reporter systems such as DR5::GUS and DR5::GFP have usually been used as indicators of gravitropic response in roots and hypocotyls of Arabidopsis. However, in the inflorescence stems, the reporter systems don't work well to monitor gravitropic response. Here, we aim to certify appropriate gravitropic response indicators (GRIs) in inflorescence stems. We performed microarray analysis comparing gene expression profiles between upper and lower flanks of Arabidopsis inflorescence stems after gravistimulation. Thirty genes showed > 2-fold differentially increased expression in lower flanks at 30 min, of which 19 were auxin response genes. We focused on IAA5 and IAA2 and verified whether they are appropriate GRIs by real-time qRT-PCR analyses. Transcript levels of IAA5 and IAA2 were remarkably higher in lower flanks than in upper flanks after gravistimulation. The biased IAA5 or IAA2 expression is disappeared in sgr2-1 mutant which is defective in gravity perception, indicating that gravity perception process is essential for formation of the biased gene expression during gravitropism. IAA5 expression was remarkably increased in lower flanks at 30 min after gravistimulation, whereas IAA2 expression was gradually decreased in upper flanks in a time-dependent manner. Therefore, we conclude that IAA5 is a sensitive GRI to monitor asymmetric auxin signaling caused by gravistimulation in Arabidopsis inflorescence stems.
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Affiliation(s)
- Masatoshi Taniguchi
- Graduate School of Bioagricultural Sciences; Nagoya University; Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Moritaka Nakamura
- Institute of Biochemistry and Biology; Plant Physiology; University of Potsdam; Potsdam-Golm, Germany
| | - Masao Tasaka
- Graduate School of Biological Sciences; Nara Institute of Science and Technology; Takayama, Ikoma, Nara, Japan
| | - Miyo Terao Morita
- Graduate School of Bioagricultural Sciences; Nagoya University; Furo-cho, Chikusa-ku, Nagoya, Japan
- Correspondence to: Miyo Terao Morita,
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Du H, Wu N, Chang Y, Li X, Xiao J, Xiong L. Carotenoid deficiency impairs ABA and IAA biosynthesis and differentially affects drought and cold tolerance in rice. PLANT MOLECULAR BIOLOGY 2013; 83:475-88. [PMID: 23846670 DOI: 10.1007/s11103-013-0103-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 07/03/2013] [Indexed: 05/24/2023]
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Schenck CA, Nadella V, Clay SL, Lindner J, Abrams Z, Wyatt SE. A proteomics approach identifies novel proteins involved in gravitropic signal transduction. AMERICAN JOURNAL OF BOTANY 2013; 100:194-202. [PMID: 23281391 DOI: 10.3732/ajb.1200339] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
PREMISE Plant organs use gravity as a guide to direct their growth. And although gravitropism has been studied since the time of Darwin, the mechanisms of signal transduction, those that connect the biophysical stimulus perception and the biochemical events of the response, are still not understood. METHODS A quantitative proteomics approach was used to identify key proteins during the early events of gravitropism. Plants were subjected to a gravity persistent signal (GPS) treatment, and proteins were extracted from the inflorescence stem at early time points after stimulation. Proteins were labeled with isobaric tags for relative and absolute quantification (iTRAQ) reagents. Proteins were identified and quantified as a single step using tandem mass-spectrometry (MS/MS). For two of the proteins identified, mutants with T-DNA inserts in the corresponding genes were evaluated for gravitropic phenotypes. KEY RESULTS A total of 82 proteins showed significant differential quantification between treatment and controls. Proteins were categorized into functional groups based on gene ontology terms and filtered using groups thought to be involved in the signaling events of gravitropism. For two of the proteins selected, GSTF9 and HSP81-2, knockout mutations resulted in defects in root skewing, waving, and curvature as well as in the GPS response of inflorescence stems. CONCLUSION Combining a proteomics approach with the GPS response, 82 novel proteins were identified to be involved in the early events of gravitropic signal transduction. As early as 2 and 4 min after a gravistimulation, significant changes occur in protein abundance. The approach was validated through the analysis of mutants exhibiting altered gravitropic responses.
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Affiliation(s)
- Craig A Schenck
- Department of Environmental and Plant Biology, Ohio University, Athens, Ohio 45701, USA
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Withers JC, Shipp MJ, Rupasinghe SG, Sukumar P, Schuler MA, Muday GK, Wyatt SE. Gravity Persistent Signal 1 (GPS1) reveals novel cytochrome P450s involved in gravitropism. AMERICAN JOURNAL OF BOTANY 2013; 100:183-193. [PMID: 23284057 DOI: 10.3732/ajb.1200436] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
PREMISE Gravity is an important environmental factor that affects growth and development of plants. In response to changes in gravity, directional growth occurs along the major axes and lateral branches of both shoots and roots. The gravity persistent signal (gps) mutants of Arabidopsis thaliana were previously identified as having an altered response to gravity when reoriented relative to the gravity vector in the cold, with the gps1 mutant exhibiting a complete loss of tropic response under these conditions. METHODS Thermal asymmetric interlaced (TAIL) PCR was used to identify the gene defective in gps1. Gene expression data, molecular modeling and computational substrate dockings, quantitative RT-PCR analyses, reporter gene fusions, and physiological analyses of knockout mutants were used to characterize the genes identified. RESULTS Cloning of the gene defective in gps1 and genetic complementation revealed that GPS1 encodes CYP705A22, a cytochrome P450 monooxygenase (P450). CYP705A5, a closely related family member, was identified as expressed specifically in roots in response to gravistimulation, and a mutation affecting its expression resulted in a delayed gravity response, increased flavonol levels, and decreased basipetal auxin transport. Molecular modeling coupled with in silico substrate docking and diphenylboric acid 2-aminoethyl ester (DBPA) staining indicated that these P450s are involved in biosynthesis of flavonoids potentially involved in auxin transport. CONCLUSION The characterization of two novel P450s (CYP705A22 and CYP705A5) and their role in the gravity response has offered new insights into the regulation of the genetic and physiological controls of plant gravitropism.
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Affiliation(s)
- John C Withers
- Department of Environmental and Plant Biology, 317 Porter Hall, Ohio University, Athens, Ohio 45701, USA
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Abstract
The growth hormone auxin regulates essentially all aspects of plant developmental processes under optimum condition. However, as a sessile organism, plants encounter both optimal and non-optimal conditions during their life cycle. Various biotic and abiotic stresses affect the growth and development of plants. Although several phytohormones, such as salicylic acid, jasmonate and ethylene, have been shown to play central roles in regulating the plant development under biotic stresses, the knowledge of the role of hormones, particularly auxin, in abiotic stresses is limiting. Among the abiotic stresses, cold stress is one of the major stress in limiting the plant development and crop productivity. This review focuses on the role of auxin in developmental regulation of plants under cold stress. The emerging trend from the recent experiments suggest that cold stress induced change in the plant growth and development is tightly linked to the intracellular auxin gradient, which is regulated by the polar deployment and intracellular trafficking of auxin carriers.
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Affiliation(s)
- Abidur Rahman
- Cryobiofrontier Research Center, Iwate University, Ueda 020-8550, Japan.
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Du H, Wu N, Fu J, Wang S, Li X, Xiao J, Xiong L. A GH3 family member, OsGH3-2, modulates auxin and abscisic acid levels and differentially affects drought and cold tolerance in rice. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:6467-80. [PMID: 23112280 PMCID: PMC3504496 DOI: 10.1093/jxb/ers300] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plant responses to abiotic stresses are coordinated by arrays of growth and developmental processes. Indole-3-acetic acid (IAA) and abscisic acid (ABA) play critical roles in developmental programmes and environmental responses, respectively, through complex signalling and metabolism networks. However, crosstalk between the two phytohormones in the stress responses remains largely unknown. Here, it is reported that a GH3 family gene, OsGH3-2, encoding an enzyme catalysing IAA conjugation to amino acids, is involved in the modulation of ABA level and stress tolerance. Expression of OsGH3-2 was induced by drought but was suppressed by cold. Overexpression of OsGH3-2 in rice caused significant morphological aberrations related to IAA deficiency, such as dwarfism, smaller leaves, and fewer crown roots and root hairs. The overexpressing line showed significantly reduced carotene, ABA, and free IAA levels, greater stomata aperture, and faster water loss, and was hypersensitive to drought stress. However, the overexpressing line showed increased cold tolerance, which was due to the combined effects of reduced free IAA content, alleviated oxidative damage, and decreased membrane penetrability. Furthermore, expression levels of some ABA synthesis- and stress-related genes were significantly changed in the overexpression line. It was conclude that OsGH3-2 modulates both endogenous free IAA and ABA homeostasis and differentially affects drought and cold tolerance in rice.
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Affiliation(s)
- Hao Du
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
| | - Nai Wu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jing Fu
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
| | - Shiping Wang
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xianghua Li
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jinghua Xiao
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
| | - Lizhong Xiong
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, PR China
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Shibasaki K, Uemura M, Tsurumi S, Rahman A. Auxin response in Arabidopsis under cold stress: underlying molecular mechanisms. THE PLANT CELL 2009; 21:3823-38. [PMID: 20040541 PMCID: PMC2814496 DOI: 10.1105/tpc.109.069906] [Citation(s) in RCA: 188] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 11/28/2009] [Accepted: 12/09/2009] [Indexed: 05/17/2023]
Abstract
To understand the mechanistic basis of cold temperature stress and the role of the auxin response, we characterized root growth and gravity response of Arabidopsis thaliana after cold stress, finding that 8 to 12 h at 4 degrees C inhibited root growth and gravity response by approximately 50%. The auxin-signaling mutants axr1 and tir1, which show a reduced gravity response, responded to cold treatment like the wild type, suggesting that cold stress affects auxin transport rather than auxin signaling. Consistently, expression analyses of an auxin-responsive marker, IAA2-GUS, and a direct transport assay confirmed that cold inhibits root basipetal (shootward) auxin transport. Microscopy of living cells revealed that trafficking of the auxin efflux carrier PIN2, which acts in basipetal auxin transport, was dramatically reduced by cold. The lateral relocalization of PIN3, which has been suggested to mediate the early phase of root gravity response, was also inhibited by cold stress. Additionally, cold differentially affected various protein trafficking pathways. Furthermore, the inhibition of protein trafficking by cold is independent of cellular actin organization and membrane fluidity. Taken together, these results suggest that the effect of cold stress on auxin is linked to the inhibition of intracellular trafficking of auxin efflux carriers.
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Affiliation(s)
- Kyohei Shibasaki
- Cryobiofrontier Research Center, Faculty of Agriculture, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Matsuo Uemura
- Cryobiofrontier Research Center, Faculty of Agriculture, Iwate University, Morioka, Iwate, 020-8550, Japan
| | - Seiji Tsurumi
- Center for Supports to Research and Education Activities Isotope Division, Kobe University, Nada, Kobe, 657-8501, Japan
| | - Abidur Rahman
- Cryobiofrontier Research Center, Faculty of Agriculture, Iwate University, Morioka, Iwate, 020-8550, Japan
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Abstract
This protocol allows the measurement of auxin transport in roots, hypocotyls and inflorescences of Arabidopsis thaliana plants by examining transport of radiolabeled auxin or movement of an auxin-induced gene expression signal. The protocol contains four stages: seedling growth, auxin application, a transport period of variable length, and quantification of auxin movement or reporter expression. Beyond the time for plant growth, the transport assay can be completed within 4-18 h. Auxin is applied to seedlings in agar cylinders or droplets, which does not require specialized liquid-handling equipment or micromanipulators, in contrast with methods that apply auxin in liquid droplets. Spatial control of auxin application is reduced, but this method has the advantages of being technically more feasible for most laboratories and allowing agar containing radioactive auxin to be removed for pulse chase assays that determine transport rates. These methods allow investigation of genetic and environmental factors that control auxin transport.
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Affiliation(s)
- Daniel R Lewis
- Department of Biology, Wake Forest University, Winston-Salem, North Carolina, USA
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Schlicht M, Strnad M, Scanlon MJ, Mancuso S, Hochholdinger F, Palme K, Volkmann D, Menzel D, Baluska F. Auxin immunolocalization implicates vesicular neurotransmitter-like mode of polar auxin transport in root apices. PLANT SIGNALING & BEHAVIOR 2006; 1:122-33. [PMID: 19521492 PMCID: PMC2635008 DOI: 10.4161/psb.1.3.2759] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Accepted: 04/03/2006] [Indexed: 05/18/2023]
Abstract
Immunolocalization of auxin using a new specific antibody revealed, besides the expected diffuse cytoplasmic signal, enrichments of auxin at end-poles (cross-walls), within endosomes and within nuclei of those root apex cells which accumulate abundant F-actin at their end-poles. In Brefeldin A (BFA) treated roots, a strong auxin signal was scored within BFA-induced compartments of cells having abundant actin and auxin at their end-poles, as well as within adjacent endosomes, but not in other root cells. Importantly, several types of polar auxin transport (PAT) inhibitors exert similar inhibitory effects on endocytosis, vesicle recycling, and on the enrichments of F-actin at the end-poles. These findings indicate that auxin is transported across F-actin-enriched end-poles (synapses) via neurotransmitter-like secretion. This new concept finds genetic support from the semaphore1, rum1 and rum1/lrt1 mutants of maize which are impaired in PAT, endocytosis and vesicle recycling, as well as in recruitment of F-actin and auxin to the auxin transporting end-poles. Although PIN1 localizes abundantly to the end-poles, and they also fail to support the formation of in these mutants affected in PAT, auxin and F-actin are depleted from their end-poles which also fail to support formation of the large BFA-induced compartments.
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Affiliation(s)
- Markus Schlicht
- IZMB; Rheinische Friedrich-Wilhelms-Universität; Bonn, Germany
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