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Bioinformatic and experimental evidence for suicidal and catalytic plant THI4s. Biochem J 2020; 477:2055-2069. [PMID: 32441748 DOI: 10.1042/bcj20200297] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 12/14/2022]
Abstract
Like fungi and some prokaryotes, plants use a thiazole synthase (THI4) to make the thiazole precursor of thiamin. Fungal THI4s are suicide enzymes that destroy an essential active-site Cys residue to obtain the sulfur atom needed for thiazole formation. In contrast, certain prokaryotic THI4s have no active-site Cys, use sulfide as sulfur donor, and are truly catalytic. The presence of a conserved active-site Cys in plant THI4s and other indirect evidence implies that they are suicidal. To confirm this, we complemented the Arabidopsistz-1 mutant, which lacks THI4 activity, with a His-tagged Arabidopsis THI4 construct. LC-MS analysis of tryptic peptides of the THI4 extracted from leaves showed that the active-site Cys was predominantly in desulfurated form, consistent with THI4 having a suicide mechanism in planta. Unexpectedly, transcriptome data mining and deep proteome profiling showed that barley, wheat, and oat have both a widely expressed canonical THI4 with an active-site Cys, and a THI4-like paralog (non-Cys THI4) that has no active-site Cys and is the major type of THI4 in developing grains. Transcriptomic evidence also indicated that barley, wheat, and oat grains synthesize thiamin de novo, implying that their non-Cys THI4s synthesize thiazole. Structure modeling supported this inference, as did demonstration that non-Cys THI4s have significant capacity to complement thiazole auxotrophy in Escherichia coli. There is thus a prima facie case that non-Cys cereal THI4s, like their prokaryotic counterparts, are catalytic thiazole synthases. Bioenergetic calculations show that, relative to suicide THI4s, such enzymes could save substantial energy during the grain-filling period.
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Griffiths CA, Reynolds MP, Paul MJ. Combining yield potential and drought resilience in a spring wheat diversity panel. Food Energy Secur 2020; 9:e241. [PMID: 33391733 PMCID: PMC7771037 DOI: 10.1002/fes3.241] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 07/22/2020] [Indexed: 12/23/2022] Open
Abstract
Pressures of population growth and climate change require the development of resilient higher yielding crops, particularly to drought. A spring wheat diversity panel was developed to combine high-yield potential with resilience. To assess performance under drought, which in many environments is intermittent and dependent on plant development, 150 lines were grown with drought imposed for 10 days either at jointing or at anthesis stages in Obregon, Mexico. Both drought treatments strongly reduced grain numbers compared with the fully irrigated check. Best performers under drought at jointing had more grain than poor performers, while best performers under drought at anthesis had larger grain than poor performers. Most high-yielding lines were high yielding in one drought environment only. However, some of the best-performing lines displayed yield potential and resilience across two environments (28 lines), particularly for yield under well-watered and drought at jointing, where yield was most related to grain numbers. Strikingly, only three lines were high yielding across all three environments, and interestingly, these lines had high grain numbers. Among parameters measured in leaves and grain, leaf relative water content did not correlate with yield, and proline was negatively correlated with yield; there were small but significant relationships between leaf sugars and yield. This study provides a valuable resource for further crosses and for elucidating genes and mechanisms that may contribute to grain number and grain filling conservation to combine yield potential and drought resilience.
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Figueiredo R, Portilla Llerena JP, Kiyota E, Ferreira SS, Cardeli BR, de Souza SCR, Dos Santos Brito M, Sodek L, Cesarino I, Mazzafera P. The sugarcane ShMYB78 transcription factor activates suberin biosynthesis in Nicotiana benthamiana. PLANT MOLECULAR BIOLOGY 2020; 104:411-427. [PMID: 32813231 DOI: 10.1007/s11103-020-01048-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/06/2020] [Indexed: 05/11/2023]
Abstract
KEY MESSAGE A sugarcane MYB present in the culm induces suberin biosynthesis and is involved both with fatty acid and phenolics metabolism. Few transcription factors have been described as regulators of cell wall polymers deposition in C4 grasses. Particularly, regulation of suberin biosynthesis in this group of plants remains poorly understood. Here, we showed that the sugarcane MYB transcription factor ShMYB78 is an activator of suberin biosynthesis and deposition. ShMYB78 was identified upon screening genes whose expression was upregulated in sugarcane internodes undergoing suberization during culm development or triggered by wounding. Agrobacterium-mediated transient expression of ShMYB78 in Nicotiana benthamiana leaves induced the ectopic deposition of suberin and its aliphatic and aromatic monomers. Further, the expression of suberin-related genes was induced by ShMYB78 heterologous expression in Nicotiana benthamiana leaves. ShMYB78 was shown to be a nuclear protein based on its presence in sugarcane internode nuclear protein extracts, and protoplast transactivation assays demonstrated that ShMYB78 activates the promoters of the sugarcane suberin biosynthetic genes β-ketoacyl-CoA synthase (ShKCS20) and caffeic acid-O-methyltransferase (ShCOMT). Our results suggest that ShMYB78 may be involved in the transcriptional regulation of suberin deposition, from fatty acid metabolism to phenylpropanoid biosynthesis, in sugarcane internodes.
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Affiliation(s)
- Raquel Figueiredo
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil.
- Department of Biology, Faculdade de Ciências, Universidade Do Porto, Rua Do Campo Alegre S/N, 4169-007, Porto, Portugal.
| | - Juan Pablo Portilla Llerena
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil
| | - Eduardo Kiyota
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil
| | - Sávio Siqueira Ferreira
- Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo, 05508-090, Brazil
| | - Bárbara Rocha Cardeli
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil
| | - Sarah Caroline Ribeiro de Souza
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil
- Department of Botany, Federal University of São Carlos, PO Box 676, São Carlos, São Paulo, 13565-905, Brazil
| | - Michael Dos Santos Brito
- Institute of Science and Technology, Federal University of São Paulo, Campus São José dos Campos, São José dos Campos, 12231-280, Brazil
| | - Ladaslav Sodek
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil
| | - Igor Cesarino
- Department of Botany, Institute of Biosciences, University of São Paulo, São Paulo, 05508-090, Brazil
| | - Paulo Mazzafera
- Department of Plant Biology, Institute of Biology, State University of Campinas, Campinas, 13083-862, Brazil
- Department of Crop Science, College of Agriculture Luiz de Queiroz, University of São Paulo, Piracicaba, 13418-900, Brazil
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Huang J, Lu G, Liu L, Raihan MS, Xu J, Jian L, Zhao L, Tran TM, Zhang Q, Liu J, Li W, Wei C, Braun DM, Li Q, Fernie AR, Jackson D, Yan J. The Kernel Size-Related Quantitative Trait Locus qKW9 Encodes a Pentatricopeptide Repeat Protein That Aaffects Photosynthesis and Grain Filling. PLANT PHYSIOLOGY 2020; 183:1696-1709. [PMID: 32482908 PMCID: PMC7401109 DOI: 10.1104/pp.20.00374] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 05/19/2020] [Indexed: 05/10/2023]
Abstract
In maize (Zea mays), kernel weight is an important component of yield that has been selected during domestication. Many genes associated with kernel weight have been identified through mutant analysis. Most are involved in the biogenesis and functional maintenance of organelles or other fundamental cellular activities. However, few quantitative trait loci (QTLs) underlying quantitative variation in kernel weight have been cloned. Here, we characterize a QTL, qKW9, associated with maize kernel weight. This QTL encodes a DYW motif pentatricopeptide repeat protein involved in C-to-U editing of ndhB, a subunit of the chloroplast NADH dehydrogenase-like complex. In a null qkw9 background, C-to-U editing of ndhB was abolished, and photosynthesis was reduced, resulting in less maternal photosynthate available for grain filling. Characterization of qKW9 highlights the importance of optimizing photosynthesis for maize grain yield production.
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Affiliation(s)
- Juan Huang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Gang Lu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Lei Liu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Mohammad Sharif Raihan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Jieting Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Wimi Biotechnology Company, Xinbei District, Changzhou City, Jiangsu 213000, China
| | - Liumei Jian
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Lingxiao Zhao
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
- Jiangsu Xuzhou Sweetpotato Research Center, Xuzhou, Jiangsu 221000, China
| | - Thu M Tran
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, Missouri 65211
| | - Qinghua Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Jie Liu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Wenqiang Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Cunxu Wei
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - David M Braun
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, Missouri 65211
| | - Qing Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Alisdair R Fernie
- Department of Molecular Physiology, Max-Planck-Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - David Jackson
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Jianbing Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
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Zhang Z, Gong J, Wang B, Li X, Ding Y, Yang B, Zhu C, Liu M, Zhang W. Regrowth strategies of Leymus chinensis in response to different grazing intensities. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02113. [PMID: 32112460 DOI: 10.1002/eap.2113] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 01/07/2020] [Accepted: 01/29/2020] [Indexed: 06/10/2023]
Abstract
In temperate grassland ecosystems, grazing can affect plant growth by foraging, trampling, and excretion. The ability of dominant plant species to regrow after grazing is critical, since it allows the regeneration of photosynthetic tissues to support growth. We conducted a field experiment to evaluate the effects of different grazing intensities (control, light, medium, and heavy) on the physiological and biochemical responses of Leymus chinensis and the carbon (C) sources utilized during regrowth. Light grazing promoted regrowth and photoassimilate storage of L. chinensis, by increasing the net photosynthetic rate (Pn ), photosynthetic quenching, light interception, sugar accumulation, sucrose synthase activities, and fructose supply from stems. At medium grazing intensity, L. chinensis had low Pn , light interception, and sugar accumulation, but higher expression of a sucrose transporter gene (LcSUT1) and water-use efficiency, which reflected a tendency to store C in belowground to promote survival. This strategy was associated with regulation by abscisic acid (ABA), jasmonate, and salicylic acid (SA) signaling. However, L. chinensis tolerated heavy grazing by increased ABA and jasmonate-induced promotion of C assimilation and osmotic adjustment, combined with photoprotection against photo-oxidation, suggesting a strategy based on regrowth. In addition, stems were the main C source organs and energy supply rather than roots. Simultaneously, SA represented a weaker defense than ABA and jasmonate. Therefore, L. chinensis adopted different strategies for regrowth under different grazing intensities, and light grazing promoted regrowth the most. Our results demonstrate the regulation of C reserves utilization by phytohormones, and this regulation provides an explanation for recent results about grazing responses.
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Affiliation(s)
- Zihe Zhang
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Jirui Gong
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
- Beijing Key Laboratory of Traditional Chinese Medicine Protection and Utilization, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Biao Wang
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Xiaobing Li
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Yong Ding
- Grassland Research Institute of Chinese Academic of Agricultural Science, Hohhot, Inner Mongolia, 010021, China
| | - Bo Yang
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Chenchen Zhu
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Min Liu
- Key Laboratory of Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China
| | - Wei Zhang
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, 100875, China
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Zhang K, Guo L, Cheng W, Liu B, Li W, Wang F, Xu C, Zhao X, Ding Z, Zhang K, Li K. SH1-dependent maize seed development and starch synthesis via modulating carbohydrate flow and osmotic potential balance. BMC PLANT BIOLOGY 2020; 20:264. [PMID: 32513104 PMCID: PMC7282075 DOI: 10.1186/s12870-020-02478-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 06/01/2020] [Indexed: 05/23/2023]
Abstract
BACKGROUND As the main form of photoassimilates transported from vegetative tissues to the reproductive organs, sucrose and its degradation products are crucial for cell fate determination and development of maize kernels. Despite the relevance of sucrose synthase SH1 (shrunken 1)-mediated release of hexoses for kernel development, the underlying physiological and molecular mechanisms are not yet well understood in maize (Zea mays). RESULTS Here, we identified a new allelic mutant of SH1 generated by EMS mutagenesis, designated as sh1*. The mutation of SH1 caused more than 90% loss of sucrose synthase activity in sh1* endosperm, which resulted in a significant reduction in starch contents while a dramatic increase in soluble sugars. As a result, an extremely high osmolality in endosperm cells of sh1* was generated, which caused kernel swelling and affected the seed development. Quantitative measurement of phosphorylated sugars showed that Glc-1-P in endosperm of sh1* (17 μg g- 1 FW) was only 5.2% of that of wild-type (326 μg g- 1 FW). As a direct source of starch synthesis, the decrease of Glc-1-P may cause a significant reduction in carbohydrates that flow to starch synthesis, ultimately contributing to the defects in starch granule development and reduction of starch content. CONCLUSIONS Our results demonstrated that SH1-mediated sucrose degradation is critical for maize kernel development and starch synthesis by regulating the flow of carbohydrates and maintaining the balance of osmotic potential.
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Affiliation(s)
- Ke Zhang
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237 China
| | - Li Guo
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237 China
| | - Wen Cheng
- Maize Institute of Shandong Academy of Agricultural Sciences, Jinan, Shandong China
| | - Baiyu Liu
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237 China
| | - Wendi Li
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237 China
| | - Fei Wang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Changzheng Xu
- School of Life Sciences, Southwest University, Chongqing, 400715 China
| | - Xiangyu Zhao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, 271018 Shandong China
| | - Zhaohua Ding
- Maize Institute of Shandong Academy of Agricultural Sciences, Jinan, Shandong China
| | - Kewei Zhang
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237 China
| | - Kunpeng Li
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237 China
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Shen S, Liang XG, Zhang L, Zhao X, Liu YP, Lin S, Gao Z, Wang P, Wang ZM, Zhou SL. Intervening in sibling competition for assimilates by controlled pollination prevents seed abortion under postpollination drought in maize. PLANT, CELL & ENVIRONMENT 2020; 43:903-919. [PMID: 31851373 DOI: 10.1111/pce.13704] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2019] [Accepted: 12/07/2019] [Indexed: 06/10/2023]
Abstract
During maize production, drought throughout the flowering stage usually induces seed abortion and yield losses. The influence of postpollination drought stress on seed abortion and its underlying mechanisms are not well characterized. By intervening in the competition for assimilates between kernel siblings under different degrees of postpollination drought stresses accompanied by synchronous pollination (SP) and incomplete pollination (ICP) approaches, the mechanisms of postpollination abortion were investigated at physiological and molecular levels. Upon SP treatment, up to 15% of the fertilized apical kernels were aborted in the drought-exacerbated competition for assimilates. The aborted kernels exhibited weak sucrose hydrolysis and starch synthesis but promoted the synthesis of trehalose-6-phosphate and ethylene. In ICP where basal pollination was prevented, apical kernel growth was restored with reinstated sucrose metabolism and starch synthesis and promoted sucrose and hexose levels under drought stress. In addition, the equilibrium between ethylene and polyamine in response to the drought and pollination treatments was associated with the abortion process. We conclude that competition for assimilates drives postpollination kernel abortion, whereas differences in sugar metabolism and the equilibrium between ethylene and polyamines may be relevant to the "live or die" choice of kernel siblings during this competition.
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Affiliation(s)
- Si Shen
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
| | - Xiao-Gui Liang
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
| | - Li Zhang
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
- College of Agronomy, Henan Agricultural University, Zhengzhou, China
| | - Xue Zhao
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
| | - Yun-Peng Liu
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
- School of Biological and Environmental Engineering, Binzhou University, Binzhou, China
| | - Shan Lin
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
| | - Zhen Gao
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
| | - Pu Wang
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
- Scientific Observing and Experimental Station of Wuqiao for Crop Water Use Efficiency, Ministry of Agriculture and Rural Affairs, Wuqiao, China
- Innovation Center of Agricultural Technology for Lowland Plain of Hebei, Wuqiao, China
| | - Zhi-Min Wang
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
- Scientific Observing and Experimental Station of Wuqiao for Crop Water Use Efficiency, Ministry of Agriculture and Rural Affairs, Wuqiao, China
- Innovation Center of Agricultural Technology for Lowland Plain of Hebei, Wuqiao, China
| | - Shun-Li Zhou
- College of Agronomy & Biotechnology, China Agricultural University, Beijing, China
- Scientific Observing and Experimental Station of Wuqiao for Crop Water Use Efficiency, Ministry of Agriculture and Rural Affairs, Wuqiao, China
- Innovation Center of Agricultural Technology for Lowland Plain of Hebei, Wuqiao, China
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Zakaria NI, Ismail MR, Awang Y, Megat Wahab PE, Berahim Z. Effect of Root Restriction on the Growth, Photosynthesis Rate, and Source and Sink Relationship of Chilli ( Capsicum annuum L.) Grown in Soilless Culture. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2706937. [PMID: 32090071 PMCID: PMC7008264 DOI: 10.1155/2020/2706937] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 07/08/2019] [Accepted: 08/09/2019] [Indexed: 11/17/2022]
Abstract
Chilli (Capsicum annum L.) plant is a high economic value vegetable in Malaysia, cultivated in soilless culture containers. In soilless culture, the adoption of small container sizes to optimize the volume of the growing substrate could potentially reduce the production cost, but will lead to a reduction of plant growth and yield. By understanding the physiological mechanism of the growth reduction, several potential measures could be adopted to improve yield under restricted root conditions. The mechanism of growth reduction of plants subjected to root restriction remains unclear. This study was conducted to determine the physiological mechanism of growth reduction of root-restricted chilli plants grown in polyvinyl-chloride (PVC) column of two different volumes, 2392 cm3(root-restricted) and 9570 cm3(control) in soilless culture. Root restriction affected plant growth, physiological process, and yield of chilli plants. Root restriction reduced the photosynthesis rate and photochemical activity of PSII, and increased relative chlorophyll content. Limited root growth in root restriction caused an accumulation of high levels of sucrose in the stem and suggested a transition of the stem as a major sink organ for photoassimilate. Growth reduction in root restriction was not related to limited carbohydrate production, but due to the low sink demand from the roots. Reduction of the total yield per plant about, 23% in root restriction was concomitant, with a slightly increased harvest index which reflected an increased photoassimilate partitioning to the fruit production and suggested more efficient fruits production in the given small plant size of root restriction.
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Affiliation(s)
- Nurul Idayu Zakaria
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Mohd Razi Ismail
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Yahya Awang
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Puteri Edaroyati Megat Wahab
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Zulkarami Berahim
- Laboratory of Climate-Smart Food Crop Production, Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
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Du Y, Zhao Q, Chen L, Yao X, Zhang H, Wu J, Xie F. Effect of Drought Stress during Soybean R2-R6 Growth Stages on Sucrose Metabolism in Leaf and Seed. Int J Mol Sci 2020; 21:E618. [PMID: 31963537 PMCID: PMC7013680 DOI: 10.3390/ijms21020618] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 01/12/2020] [Accepted: 01/14/2020] [Indexed: 12/20/2022] Open
Abstract
Sucrose is the main photosynthesis product of plants and the fundamental carbon skeleton monomer and energy supply for seed formation and development. Drought stress induces decreased photosynthetic carbon assimilation capacity, and seriously affects seed weight in soybean. However, little is known about the relationship between decreases in soybean seed yield and disruption of sucrose metabolism and transport balance in leaves and seeds during the reproductive stages of crop growth. Three soybean cultivars with similar growth periods, "Shennong17", "Shennong8", and "Shennong12", were subjected to drought stress during reproductive growth for 45 days. Drought stress significantly reduced leaf photosynthetic rate, shoot biomass, and seed weight by 63.93, 33.53, and 41.65%, respectively. Drought stress increased soluble sugar contents, the activities of sucrose phosphate synthase, sucrose synthase, and acid invertase enzymes, and up-regulated the expression levels of GmSPS1, GmSuSy2, and GmA-INV, but decreased starch content by 15.13% in leaves. Drought stress decreased the contents of starch, fructose, and glucose in seeds during the late seed filling stages, while it induced sucrose accumulation, which resulted in a decreased hexose-to-sucrose ratio. In developing seeds, the activities of sucrose synthesis and degradation enzymes, the expression levels of genes related to metabolism, and the expression levels of sucrose transporter genes were enhanced during early seed development under drought stress; however, under prolonged drought stress, all of them decreased. These results demonstrated that drought stress enhances the capacity for unloading sucrose into seeds and activated sucrose metabolism during early seed development. At the middle and late seed filling stages, sucrose flow from leaves to seeds was diminished, and the balance of sucrose metabolism was impaired in seeds, resulting in seed mass reduction. The different regulation strategies in sucrose allocation, metabolism, and transport during different seed development stages may be one of the physiological mechanisms for soybean plants to resist drought stress.
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Affiliation(s)
- Yanli Du
- Soybean Research Institute, Shenyang Agricultural University, Shenyang 110866, China; (Y.D.); (Q.Z.); (L.C.); (X.Y.); (H.Z.)
| | - Qiang Zhao
- Soybean Research Institute, Shenyang Agricultural University, Shenyang 110866, China; (Y.D.); (Q.Z.); (L.C.); (X.Y.); (H.Z.)
| | - Liru Chen
- Soybean Research Institute, Shenyang Agricultural University, Shenyang 110866, China; (Y.D.); (Q.Z.); (L.C.); (X.Y.); (H.Z.)
| | - Xingdong Yao
- Soybean Research Institute, Shenyang Agricultural University, Shenyang 110866, China; (Y.D.); (Q.Z.); (L.C.); (X.Y.); (H.Z.)
| | - Huijun Zhang
- Soybean Research Institute, Shenyang Agricultural University, Shenyang 110866, China; (Y.D.); (Q.Z.); (L.C.); (X.Y.); (H.Z.)
| | - Junjiang Wu
- Soybean Research Institute of Heilongjiang Academy of Agricultural Sciences, Key Laboratory of Soybean Cultivation of Ministry of Agriculture P. R. China, Harbin 150086, China;
| | - Futi Xie
- Soybean Research Institute, Shenyang Agricultural University, Shenyang 110866, China; (Y.D.); (Q.Z.); (L.C.); (X.Y.); (H.Z.)
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Du Y, Zhao Q, Chen L, Yao X, Zhang W, Zhang B, Xie F. Effect of drought stress on sugar metabolism in leaves and roots of soybean seedlings. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 146:1-12. [PMID: 31710920 DOI: 10.1016/j.plaphy.2019.11.003] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 10/31/2019] [Accepted: 11/02/2019] [Indexed: 05/19/2023]
Abstract
Sucrose is the main photosynthetic product in plants, and acts as a major energy substrate and signaling regulator of plant growth. Furthermore, sucrose is involved in the responses to various abiotic stresses. However, the role of sucrose in soybean (Glycine max L.) growth and development under drought stress remains largely unknown. In this study, the two soybean cultivars, Shennong8 (CV.SN8) and Shennong12 (CV.SN12), were grown in pot culture and subjected to three water treatments for 15 days: soil moisture contents of 75 ± 5% (CK), 45 ± 5% (MD), and 30 ± 5% (SD) of field capacity. Under drought stress, the reduction in shoot biomass was more pronounced than the reduction of biomass in the root of both soybean cultivars, resulting in higher root/shoot (R/S) ratio. Drought stress increased the contents of soluble sugar and sucrose in the leaves, but decreased starch content; in the roots, all of these parameters were increased. This may be related to the enhanced carbohydrate metabolism activity under drought stress, including notable changes in the activities of sugar metabolism enzymes and expression levels of GmSPS, GmSuSy, GmC-INV, GmA-INV, GmAMY3, and GmBAM1. Furthermore, the expression levels of sucrose transporter genes (GmSUC2, GmSWEET6, and GmSWEET15) in leaves and roots of soybean seedlings were up-regulated under drought stress. In conclusion, our results highlight that the increase in R/S ratio caused by the changes of sugar allocation, metabolism, and transport under drought stress contributes towards drought resistance of soybean.
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Affiliation(s)
- Yanli Du
- Soybean Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Qiang Zhao
- Soybean Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Liru Chen
- Soybean Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Xingdong Yao
- Soybean Research Institute, Shenyang Agricultural University, Shenyang, China
| | - Wei Zhang
- Soybean Research Institute, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Bo Zhang
- Virginia Tech Department of Crop, Soil and Environmental Sciences, Blacksburg, VA, USA
| | - Futi Xie
- Soybean Research Institute, Shenyang Agricultural University, Shenyang, China.
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Paponov IA, Paponov M, Sambo P, Engels C. Differential Regulation of Kernel Set and Potential Kernel Weight by Nitrogen Supply and Carbohydrate Availability in Maize Genotypes Contrasting in Nitrogen Use Efficiency. FRONTIERS IN PLANT SCIENCE 2020; 11:586. [PMID: 32499807 PMCID: PMC7243938 DOI: 10.3389/fpls.2020.00586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/17/2020] [Indexed: 05/15/2023]
Abstract
Sub-optimal nitrogen (N) conditions reduce maize yield due to a decrease in two sink components: kernel set and potential kernel weight. Both components are established during the lag phase, suggesting that they could compete for resources during this critical period. However, whether this competition occurs or whether different genotypic strategies exist to optimize photoassimilate use during the lag phase is not clear and requires further investigation. We have addressed this knowledge gap by conducting a nutrient solution culture experiment that allows abrupt changes in N level and light intensity during the lag phase. We investigated plant growth, dry matter partitioning, non-structural carbohydrate concentration, N concentration, and 15N distribution (applied 4 days before silking) in plant organs at the beginning and the end of the lag phase in two maize hybrids that differ in grain yield under N-limited conditions: one is a nitrogen-use-efficient (EFFI) genotype and the other is a control (GREEN) genotype that does not display high N use efficiency. We found that the two genotypes used different mechanisms to regulate kernel set. The GREEN genotype showed a reduction in kernel set associated with reduced dry matter allocation to the ear during the lag phase, indicating that the reduced kernel set under N-limited conditions was related to sink restrictions. This idea was supported by a negative correlation between kernel set and sucrose/total sugar ratios in the kernels, indicating that the capacity for sucrose cleavage might be a key factor defining kernel set in the GREEN genotype. By contrast, the kernel set of the EFFI genotype was not correlated with dry matter allocation to the ear or to a higher capacity for sucrose cleavage; rather, it showed a relationship with the different EFFI ear morphology with bigger kernels at the apex of the ear than in the GREEN genotype. The potential kernel weight was independent of carbohydrate availability but was related to the N flux per kernel in both genotypes. In conclusion, kernel set and potential kernel weight are regulated independently, suggesting the possibility of simultaneously increasing both sink components in maize.
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Affiliation(s)
- Ivan A. Paponov
- Division of Food Production and Society, Norwegian Institute of Bioeconomy Research, Ås, Norway
- *Correspondence: Ivan A. Paponov,
| | - Martina Paponov
- Division of Food Production and Society, Norwegian Institute of Bioeconomy Research, Ås, Norway
| | - Paolo Sambo
- Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, Legnaro, Italy
| | - Christof Engels
- Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences, Plant Nutrition and Fertilisation, Humboldt-Universitat zu Berlin, Berlin, Germany
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Zhao L, Xie L, Huang J, Su Y, Zhang C. Proper Glyphosate Application at Post-anthesis Lowers Grain Moisture Content at Harvest and Reallocates Non-structural Carbohydrates in Maize. FRONTIERS IN PLANT SCIENCE 2020; 11:580883. [PMID: 33362811 PMCID: PMC7758537 DOI: 10.3389/fpls.2020.580883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 11/23/2020] [Indexed: 05/03/2023]
Abstract
Glyphosate (GP)-based herbicides have been widely applied to crops for weed control and pre-harvest desiccation. The objective of this research was to evaluate the effects of pre-harvest GP application on maize or how it physiologically alters this crop. Here, we applied four GP treatment (Control, GP150, GP200, and GP250) on maize lines of Z58 and PH6WC belonging to different maturity groups at grain-filling stages form DAP30 to DAP45. GP application significantly decreased the grain moisture content at harvest by 22-35% for Z58 and by 15-41% for PH6WC. However, the responses of grain weight to glyphosate vary with inbred lines and application time. A high concentration of glyphosate (GP250) reduced the grain weight of Z58 and low concentrations (GP150 and GP200) did not affect, while the grain weight of PH6WC significantly decreased under glyphosate treatment. In summary, our results revealed that timely and appropriate GP application lowers grain moisture content without causing seed yield and quality loss. GP application adversely affected photosynthesis by promoting maturation and leaf senescence. Meanwhile, it also enhanced non-structural carbohydrate (soluble sugars and starch) remobilization from the vegetative organs to the grains. Hence, GP treatment coordinates plant senescence and assimilate remobilization. RNA sequencing revealed that glyphosate regulated the transcript levels of sugar signaling-related genes and induced assimilate repartitioning in grains. This work indicates the practical significance of GP application for maize seed production and harvest, which highlights the contributions of source-sink communication to maize yield in response to external stress or pre-harvest desiccant application.
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Cheng J, Wen S, Bie Z. Overexpression of hexose transporter CsHT3 increases cellulose content in cucumber fruit peduncle. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 145:107-113. [PMID: 31677541 DOI: 10.1016/j.plaphy.2019.10.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/01/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
Hexose transporters play many important roles in plant development. However, the role of hexose transporter in secondary cell wall growth has not been reported before. Here, we report that the hexose transporter gene CsHT3 is mainly expressed in cells with secondary cell walls in cucumber. Spatiotemporal expression analysis revealed that the transcript of CsHT3 mainly accumulates in the stem, petiole, tendril, and peduncle, all of which contain high cellulose levels. Immunolocalization results show that CsHT3 is localized at the sclereids in young peduncles, shifts to the phloem fiber cells during peduncle development, and then shifts again to the companion cells when the development of secondary cell walls is almost completed. Carboxyfluoresce unloading experiment indicated that carbohydrate unloading in the phloem follows an apoplastic pathway. Overexpression of CsHT3 in cucumber plant can improve the cellulose content and cell wall thickness of phloem fiber cells in the peduncle. The expression of cellulose synthase genes were increased in the CsHT3 overexpression plants. These results indicated that CsHT3 may play an important role in cellulose synthesis through promoting the expression of cellulose synthase genes.
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Affiliation(s)
- Jintao Cheng
- College of Horticulture and Forestry, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, PR China.
| | - Suying Wen
- College of Horticulture and Forestry, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, PR China.
| | - Zhilong Bie
- College of Horticulture and Forestry, Huazhong Agricultural University and Key Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan, 430070, PR China.
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Chen T, Li G, Islam MR, Fu W, Feng B, Tao L, Fu G. Abscisic acid synergizes with sucrose to enhance grain yield and quality of rice by improving the source-sink relationship. BMC PLANT BIOLOGY 2019; 19:525. [PMID: 31775620 PMCID: PMC6882056 DOI: 10.1186/s12870-019-2126-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 11/08/2019] [Indexed: 05/07/2023]
Abstract
BACKGROUND Abscisic acid (ABA) and sucrose act as molecular signals in response to abiotic stress. However, how their synergy regulates the source-sink relationship has rarely been studied. This study aimed to reveal the mechanism underlying the synergy between ABA and sucrose on assimilates allocation to improve grain yield and quality of rice. The early indica rice cultivar Zhefu802 was selected and planted in an artificial climate chamber at 32/24 °C (day/night) under natural sunlight conditions. Sucrose and ABA were exogenously sprayed (either alone or in combination) onto rice plants at flowering and 10 days after flowering. RESULTS ABA plus sucrose significantly improved both the grain yield and quality of rice, which was mainly a result of the higher proportion of dry matter accumulation and non-structural carbohydrates in panicles. These results were mainly ascribed to the large improvement in sucrose transport in the sheath-stems in response to the ABA plus sucrose treatment. In this process, ABA plus sucrose significantly enhanced the contents of starch, gibberellic acids, and zeatin ribosides as well as the activities and gene expression of enzymes involved in starch synthesis in grains. Additionally, remarkable increases in trehalose content and expression levels of trehalose-6-phosphate synthase1, trehalose-6-phosphate phosphatase7, and sucrose non-fermenting related protein kinase 1A were also found in grains treated with ABA plus sucrose. CONCLUSION The synergy between ABA and sucrose increased grain yield and quality by improving the source-sink relationship through sucrose and trehalose metabolism in grains.
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Affiliation(s)
- Tingting Chen
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
| | - Guangyan Li
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
| | - Mohammad Rezaul Islam
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
- Department of Agricultural Extension, Ministry of Agriculture, Dhaka, 1215 Bangladesh
| | - Weimeng Fu
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
| | - Baohua Feng
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
| | - Longxing Tao
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
| | - Guanfu Fu
- National Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 People’s Republic of China
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65
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Padhi S, Grimes MM, Muro-Villanueva F, Ortega JL, Sengupta-Gopalan C. Distinct nodule and leaf functions of two different sucrose phosphate synthases in alfalfa. PLANTA 2019; 250:1743-1755. [PMID: 31422508 DOI: 10.1007/s00425-019-03261-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/10/2019] [Indexed: 06/10/2023]
Abstract
In alfalfa, the B form of Sucrose phosphate synthase synthesizes sucrose in the leaves while the A form participates in regulatory cycles of synthesis/breakdown of sucrose/starch in the root nodules. Sucrose (Suc) is the major stable product of photosynthesis that is transported to all heterotrophic organs as a source of energy and carbon. The enzyme sucrose phosphate synthase (SPS) catalyzes the synthesis of Suc. Besides the leaves, SPS is also found in heterotrophic organs. There are two isoforms of SPS in alfalfa (Medicago sativa): SPSA and SPSB. While SPSA is expressed in the vasculature of all the organs and in the N2-fixing zone in the nodules, SPSB is exclusively expressed in the photosynthetic cells. Two classes of alfalfa transformants were produced, one with a gene construct consisting of the alfalfa SPSA promoter and the other with the SPSB promoter-both driving the maize SPS coding region-referred to as SPSA-ZmSPS and SPSB-ZmSPS, respectively. Both classes of transformants showed increased growth compared to control plants. The SPSB-ZmSPS transformants showed increased SPS protein levels and activity along with a significant increase in the Suc levels in the leaves. The SPSA-ZmSPS transformants showed an increase in the SPS protein level and enzyme activity both in the leaves and the nodules with no increase in Suc content in the leaves but a substantial increase in the nodules. Both SPSA and SPSB have unique roles in the nodules (sink) and leaves (source). SPSB is responsible for the synthesis of Suc in the photosynthetic cells and SPSA participates in a regulatory cycle in which Suc is simultaneously degraded and re-synthesized; both these functions contribute to plant growth in rhizobia nodulated alfalfa plants.
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Affiliation(s)
- Shanta Padhi
- Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, 88003, USA
| | - Martha M Grimes
- Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, 88003, USA
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM, USA
| | - Fabiola Muro-Villanueva
- Department of Biochemistry, College of Agriculture, Purdue University, West Lafayette, IN, USA
| | - Jose Luis Ortega
- Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, 88003, USA
| | - Champa Sengupta-Gopalan
- Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, 88003, USA.
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66
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Sugar starvation-regulated MYBS2 and 14-3-3 protein interactions enhance plant growth, stress tolerance, and grain weight in rice. Proc Natl Acad Sci U S A 2019; 116:21925-21935. [PMID: 31594849 DOI: 10.1073/pnas.1904818116] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Autotrophic plants have evolved distinctive mechanisms for maintaining a range of homeostatic states for sugars. The on/off switch of reversible gene expression by sugar starvation/provision represents one of the major mechanisms by which sugar levels are maintained, but the details remain unclear. α-Amylase (αAmy) is the key enzyme for hydrolyzing starch into sugars for plant growth, and it is induced by sugar starvation and repressed by sugar provision. αAmy can also be induced by various other stresses, but the physiological significance is unclear. Here, we reveal that the on/off switch of αAmy expression is regulated by 2 MYB transcription factors competing for the same promoter element. MYBS1 promotes αAmy expression under sugar starvation, whereas MYBS2 represses it. Sugar starvation promotes nuclear import of MYBS1 and nuclear export of MYBS2, whereas sugar provision has the opposite effects. Phosphorylation of MYBS2 at distinct serine residues plays important roles in regulating its sugar-dependent nucleocytoplasmic shuttling and maintenance in cytoplasm by 14-3-3 proteins. Moreover, dehydration, heat, and osmotic stress repress MYBS2 expression, thereby inducing αAmy3 Importantly, activation of αAmy3 and suppression of MYBS2 enhances plant growth, stress tolerance, and total grain weight per plant in rice. Our findings reveal insights into a unique regulatory mechanism for an on/off switch of reversible gene expression in maintaining sugar homeostatic states, which tightly regulates plant growth and development, and also highlight MYBS2 and αAmy3 as potential targets for crop improvement.
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67
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de Ï Vila Silva L, Condori-Apfata JA, Costa PMDA, Martino PBO, Tavares ACA, Marcelino MM, Raimundi SBCJR, Picoli EADT, Araï Jo WL, Zsï Gï N A, Sulpice R, Nunes-Nesi A. Source Strength Modulates Fruit Set by Starch Turnover and Export of Both Sucrose and Amino Acids in Pepper. PLANT & CELL PHYSIOLOGY 2019; 60:2319-2330. [PMID: 31268146 DOI: 10.1093/pcp/pcz128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 06/23/2019] [Indexed: 06/09/2023]
Abstract
Fruit set is an important yield-related parameter, which varies drastically due to genetic and environmental factors. Here, two commercial cultivars of Capsicum chinense (Biquinho and Habanero) were evaluated in response to light intensity (unshaded and shaded) and N supply (deficiency and sufficiency) to understand the role of source strength on fruit set at the metabolic level. We assessed the metabolic balance of primary metabolites in source leaves during the flowering period. Furthermore, we investigated the metabolic balance of the same metabolites in flowers to gain more insights into their influence on fruit set. Genotype and N supply had a strong effect on fruit set and the levels of primary metabolites, whereas light intensity had a moderate effect. Higher fruit set was mainly related to the export of both sucrose and amino acids from source leaves to flowers. Additionally, starch turnover in source leaves, but not in flowers, had a central role on the sucrose supply to sink organs at night. In flowers, our results not only confirmed the role of the daily supply of carbohydrates on fruit set but also indicated a potential role of the balance of amino acids and malate.
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Affiliation(s)
- Lucas de Ï Vila Silva
- Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
| | - Jorge A Condori-Apfata
- Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
| | | | - Pedro Brandï O Martino
- Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
| | - Ana C Azevedo Tavares
- Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
| | | | | | | | - Wagner L Araï Jo
- Max-Planck Partner Group, Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
| | - Agustin Zsï Gï N
- Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
| | - Ronan Sulpice
- Plant Systems Biology Laboratory, Ryan Institute, National University of Ireland, Galway, Ireland
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Vi�osa, Vi�osa, Minas Gerais, Brazil
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68
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Tran TM, McCubbin TJ, Bihmidine S, Julius BT, Baker RF, Schauflinger M, Weil C, Springer N, Chomet P, Wagner R, Woessner J, Grote K, Peevers J, Slewinski TL, Braun DM. Maize Carbohydrate Partitioning Defective33 Encodes an MCTP Protein and Functions in Sucrose Export from Leaves. MOLECULAR PLANT 2019; 12:1278-1293. [PMID: 31102785 DOI: 10.1016/j.molp.2019.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 04/09/2019] [Accepted: 05/03/2019] [Indexed: 05/29/2023]
Abstract
To sustain plant growth, development, and crop yield, sucrose must be transported from leaves to distant parts of the plant, such as seeds and roots. To identify genes that regulate sucrose accumulation and transport in maize (Zea mays), we isolated carbohydrate partitioning defective33 (cpd33), a recessive mutant that accumulated excess starch and soluble sugars in mature leaves. The cpd33 mutants also exhibited chlorosis in the leaf blades, greatly diminished plant growth, and reduced fertility. Cpd33 encodes a protein containing multiple C2 domains and transmembrane regions. Subcellular localization experiments showed the CPD33 protein localized to plasmodesmata (PD), the plasma membrane, and the endoplasmic reticulum. We also found that a loss-of-function mutant of the CPD33 homolog in Arabidopsis, QUIRKY, had a similar carbohydrate hyperaccumulation phenotype. Radioactively labeled sucrose transport assays showed that sucrose export was significantly lower in cpd33 mutant leaves relative to wild-type leaves. However, PD transport in the adaxial-abaxial direction was unaffected in cpd33 mutant leaves. Intriguingly, transmission electron microscopy revealed fewer PD at the companion cell-sieve element interface in mutant phloem tissue, providing a possible explanation for the reduced sucrose export in mutant leaves. Collectively, our results suggest that CPD33 functions to promote symplastic transport into sieve elements.
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Affiliation(s)
- Thu M Tran
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, MO 65211, USA; Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA; National Key Laboratory for Plant Cell Technology, Agricultural Genetics Institute, Hanoi, Vietnam
| | - Tyler J McCubbin
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, MO 65211, USA; Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Saadia Bihmidine
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, MO 65211, USA
| | - Benjamin T Julius
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, MO 65211, USA
| | - R Frank Baker
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, MO 65211, USA
| | - Martin Schauflinger
- Electron Microscopy Core Facility, University of Missouri, Columbia, MO 65211, USA
| | - Clifford Weil
- Department of Agronomy, Purdue University, West Lafayette, IN 47907, USA
| | - Nathan Springer
- Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN 55108, USA
| | - Paul Chomet
- NRGene Inc., 8910 University Center Lane, ∖r∖nSuite 400, San Diego, CA 92122, USA
| | - Ruth Wagner
- Bayer Crop Science, Chesterfield, MO 63017, USA
| | | | - Karen Grote
- Bayer Crop Science, Chesterfield, MO 63017, USA
| | | | | | - David M Braun
- Division of Biological Sciences, Interdisciplinary Plant Group, Missouri Maize Center, University of Missouri, Columbia, MO 65211, USA.
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69
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Ding X, Zeng J, Huang L, Li X, Song S, Pei Y. Senescence-induced expression of ZmSUT1 in cotton delays leaf senescence while the seed coat-specific expression increases yield. PLANT CELL REPORTS 2019; 38:991-1000. [PMID: 31069498 DOI: 10.1007/s00299-019-02421-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 04/29/2019] [Indexed: 05/16/2023]
Abstract
Sink-specific expression of a sucrose transporter protein gene from the C4 plant maize can promote carbohydrate accumulation in target tissues and increase both fiber and seed yield of cotton. Sucrose is the principal form of photosynthetic products transported from source tissue to sink tissue in higher plants. Enhancing the partition of carbohydrate to the target organ is a promising way to improve crop productivity. The C4 plant Zea mays exhibits a substantially higher rate of export of photosynthates than many C3 plants, and its sucrose transporter protein ZmSut1 displays important role in sucrose allocation. To investigate how use of ZmSUT1 gene to increase the fiber and seed yield of cotton, in this study, we expressed the gene in cotton under a senescence-inducible promoter PSAG12 and a seed coat-specific promoter BAN, respectively. We show that senescence-induced expression of ZmSUT1 results in an increase of sugar accumulation in leaves. Although the leaf senescence was postponed in PSAG12::ZmSUT1 cotton, the photosynthetic rate of the leaves was decreased. In contrast, seed coat-specific expression of the gene leads to an increase of sugar accumulation in fibers and bolls, and the leaf of transgenic BAN::ZmSUT1 cotton displayed higher photosynthetic capacity than the wild type. Importantly, both fiber and seed yield of transgenic BAN::ZmSUT1 cotton are significantly enhanced. Our data indicate the potential of enhancing yield of carbohydrate crops by the regulation of sugar partitioning.
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Affiliation(s)
- Xiaoyan Ding
- Biotechnology Research Center, Southwest University, No. 2 Tiansheng Rd., Beibei, Chongqing, 400716, People's Republic of China
| | - Jianyan Zeng
- Biotechnology Research Center, Southwest University, No. 2 Tiansheng Rd., Beibei, Chongqing, 400716, People's Republic of China
| | - Liang Huang
- Biotechnology Research Center, Southwest University, No. 2 Tiansheng Rd., Beibei, Chongqing, 400716, People's Republic of China
| | - Xianbi Li
- Biotechnology Research Center, Southwest University, No. 2 Tiansheng Rd., Beibei, Chongqing, 400716, People's Republic of China
| | - Shuiqing Song
- Biotechnology Research Center, Southwest University, No. 2 Tiansheng Rd., Beibei, Chongqing, 400716, People's Republic of China
| | - Yan Pei
- Biotechnology Research Center, Southwest University, No. 2 Tiansheng Rd., Beibei, Chongqing, 400716, People's Republic of China.
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70
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Rodrigues J, Inzé D, Nelissen H, Saibo NJM. Source-Sink Regulation in Crops under Water Deficit. TRENDS IN PLANT SCIENCE 2019; 24:652-663. [PMID: 31109763 DOI: 10.1016/j.tplants.2019.04.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 05/21/2023]
Abstract
To meet the food demands of an increasing world population, it is necessary to improve crop production; a task that is made more challenging by the changing climate. Several recent reports show that increasing the capacity of plants to assimilate carbon (source strength), or to tap into the internal carbon reservoir (sink strength), has the potential to improve plant productivity in the field under water-deficit conditions. Here, we review the effects of water deficit on the source-sink communication, as well as the respective regulatory mechanisms underpinning plant productivity. We also highlight stress-tolerant traits that can contribute to harness source and sink strengths towards producing high-yielding and drought-tolerant crops, depending on the drought scenario.
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Affiliation(s)
- Joana Rodrigues
- Instituto de Tecnologia Química e Biológica António Xavier, UNL, 2780-157 Oeiras, Portugal; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Dirk Inzé
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Hilde Nelissen
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; VIB Center for Plant Systems Biology, 9052 Ghent, Belgium.
| | - Nelson J M Saibo
- Instituto de Tecnologia Química e Biológica António Xavier, UNL, 2780-157 Oeiras, Portugal.
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Chen Z, Qin C, Wang M, Liao F, Liao Q, Liu X, Li Y, Lakshmanan P, Long M, Huang D. Ethylene-mediated improvement in sucrose accumulation in ripening sugarcane involves increased sink strength. BMC PLANT BIOLOGY 2019; 19:285. [PMID: 31253103 PMCID: PMC6599285 DOI: 10.1186/s12870-019-1882-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 06/11/2019] [Indexed: 05/23/2023]
Abstract
BACKGROUND Sugarcane is a major crop producing about 80% of sugar globally. Increasing sugar content is a top priority for sugarcane breeding programs worldwide, however, the progress is extremely slow. Owing to its commercial significance, the physiology of sucrose accumulation has been studied extensively but it did not lead to any significant practical outcomes. Recent molecular studies are beginning to recognize genes and gene networks associated with this phenomenon. To further advance our molecular understanding of sucrose accumulation, we altered sucrose content of sugarcane genotypes with inherently large variation for sucrose accumulation using a sugarcane ripener, ethylene, and studied their transcriptomes to identify genes associated with the phenomenon. RESULTS Sucrose content variation in the experimental genotypes was substantial, with the top-performing clone producing almost 60% more sucrose than the poorest performer. Ethylene treatment increased stem sucrose content but that occurred only in low-sugar genotype. Transcriptomic analyses have identified about 160,000 unigenes of which 86,000 annotated genes were classified into functional groups associated with carbohydrate metabolism, signaling, localization, transport, hydrolysis, growth, catalytic activity, membrane and storage, suggesting the structural and functional specification, including sucrose accumulation, occurring in maturing internodes. About 25,000 genes were differentially expressed between all genotypes and treatments combined. Genotype had a dominant effect on differential gene expression than ethylene treatment. Sucrose and starch metabolism genes were more responsive to ethylene treatment in low-sugar genotype. Ethylene caused differential gene expression of many stress-related transcription factors, carbohydrate metabolism, hormone metabolism and epigenetic modification. Ethylene-induced expression of ethylene-responsive transcription factors, cytosolic acid- and cell wall-bound invertases, and ATPase was more pronounced in low- than in high-sugar genotype, suggesting an ethylene-stimulated sink activity and consequent increased sucrose accumulation in low-sugar genotype. CONCLUSION Ethylene-induced sucrose accumulation is more pronounced in low-sugar sugarcane genotype, and this is possibly achieved by the preferential activation of genes such as invertases that increase sink strength in the stem. The relatively high enrichment of differentially expressed genes associated with hormone metabolism and signaling and stress suggests a strong hormonal regulation of source-sink activity, growth and sucrose accumulation in sugarcane.
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Affiliation(s)
- Zhongliang Chen
- College of Agriculture, Guangxi University, Nanning, 530004 China
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Cuixian Qin
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Miao Wang
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Fen Liao
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Qing Liao
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Xihui Liu
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Yangrui Li
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
| | - Prakash Lakshmanan
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, QLD, St Lucia, 4072 Australia
| | - Minghua Long
- College of Agriculture, Guangxi University, Nanning, 530004 China
| | - Dongliang Huang
- Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture and Rural Affairs /Guangxi Key Laboratory of Sugarcane Genetic Improvement /Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, 530007 China
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Wang C, Ning P. Post-silking Phosphorus Recycling and Carbon Partitioning in Maize Under Low to High Phosphorus Inputs and Their Effects on Grain Yield. FRONTIERS IN PLANT SCIENCE 2019; 10:784. [PMID: 31249585 PMCID: PMC6582669 DOI: 10.3389/fpls.2019.00784] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/29/2019] [Indexed: 05/30/2023]
Abstract
Phosphorus (P) recycling and carbon partitioning are crucial determinants of P-use efficiency and grain yield in maize (Zea mays), while a full understanding of how differences in P availability/plant P status affect these two processes underlying yield formation remains elusive. Field experiments were conducted for 3 years to investigate the maize growth, P remobilization, and carbohydrate accumulation in leaves and developing ears of plants receiving low to high P inputs. In plots that 75 kg P2O5 ha-1 and above was applied (corresponding to 7.5 mg kg-1 and higher Olsen-P concentration in 0-20 cm soil layer), no additional response occurred in leaf area, ear growth, and grain yield. Despite the higher P uptake with P fertilization above this threshold, the lack of additional plant growth and yield resulted in decreased P-use efficiency. Regardless of P application rates, P remobilization to the ear during the first half of the grain filling phase preferentially came from the stem (50-76%) rather than from leaves (30-44%), and with a greater proportion in the inorganic P (Pi) form over organic P fractions. Leaf photosynthesis was maintained under P-limiting conditions due to the greater P investment in organic P pools than Pi. More and larger starch granules were found in the bundle sheath cells at silking or 21 days after silking (DAS) than under P-sufficient conditions. The amount of total carbohydrate production and export was lower in the P-deficient plants than the high-P plants, corresponding to decreased leaf size and lifespan. Nonetheless, similar or significantly greater starch levels were observed in both cob and kernels at silking and 21 DAS, implying there was an adequate carbohydrate supply to the developing ears under the diminished kernel sink of the P starvation. In addition, there was a strong correlation between the accumulation rates of carbon and remobilized P in the developing kernels, as well as between carbon and total P. Overall, the results indicated that diminished sink size and lower capacity of carbon deposition may limit yield formation in P-deficient maize, which in turn imposes a feedback regulation on reducing carbon and P remobilization from source leaves. An integrated framework considering post-silking P recycling and carbon partitioning in maize and their effects on grain yield has been proposed.
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Affiliation(s)
- Chao Wang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, China
- Department of Plant Nutrition, College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Peng Ning
- College of Natural Resources and Environment, Northwest A&F University, Yangling, China
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de Ávila Silva L, Condori-Apfata JA, Marcelino MM, Tavares ACA, Raimundi SCJ, Martino PB, Araújo WL, Zsögön A, Sulpice R, Nunes-Nesi A. Nitrogen differentially modulates photosynthesis, carbon allocation and yield related traits in two contrasting Capsicum chinense cultivars. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 283:224-237. [PMID: 31128692 DOI: 10.1016/j.plantsci.2019.02.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 02/20/2019] [Accepted: 02/22/2019] [Indexed: 05/24/2023]
Abstract
Yield-related traits of Capsicum chinense are highly dependent on coordination between vegetative and reproductive growth, since the formation of reproductive tissues occurs iteratively in new sympodial bifurcations. In this study, we used two C. chinense cultivars (Biquinho and Habanero), contrasting for fruit size and fruit set, to investigate the responses of nitrogen (N) deficiency and excess on growth, photosynthesis, carbon (C) and N metabolisms as well as yield-related traits. Both cultivars increased biomass allocation to leaves in conditions of higher N supply and exhibited a parabolic behavior for fruit biomass allocation. Plants growing under N-deficiency produced a lower number of flowers and heavier fruits. Contrarily, plants under high N condition tended to decrease their CO2 assimilation rate, harvest index and fruit weight. Biquinho, the cultivar with lower fruit size and higher fruit set, was initially less affected by excess of N due to its continuous formation of new reproductive sinks in relation to Habanero (which has lower fruit set and higher fruit size). The results suggest that N amount influences sucrose supply to different organs and can differentially affect yield-related traits between Capsicum cultivars with contrasting source-sink relations.
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Affiliation(s)
- Lucas de Ávila Silva
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Jorge A Condori-Apfata
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Mariana Marques Marcelino
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Ana C Azevedo Tavares
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Sábata C Januário Raimundi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Pedro Brandão Martino
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil; Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Agustin Zsögön
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Ronan Sulpice
- National University of Ireland, Galway, Plant Systems Biology Lab, Plant and AgriBiosciences Research Centre, Ryan Institute, Ireland
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil.
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Ram H, Kaur A, Gandass N, Singh S, Deshmukh R, Sonah H, Sharma TR. Molecular characterization and expression dynamics of MTP genes under various spatio-temporal stages and metal stress conditions in rice. PLoS One 2019; 14:e0217360. [PMID: 31136613 PMCID: PMC6538162 DOI: 10.1371/journal.pone.0217360] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/09/2019] [Indexed: 11/23/2022] Open
Abstract
Metal Tolerance Proteins (MTPs) are the class of membrane proteins involved in the transport of metals, mainly Zn, Mn, Fe, Cd, Co and Ni, and confer metal tolerance in plants. In the present study, a comprehensive molecular analysis of rice MTP genes was performed to understand the evolution, distribution and expression dynamics of MTP genes. Exploration of the whole genome re-sequencing information available for three thousand rice genotypes highlighted the evolution and allelic diversity of MTP genes. Based on the presence of non-synonymous single nucleotide polymorphism (SNP), MTP1, MTP6, MTP8 and MTP9 were found to be the most conserved genes. Furthermore, results showed localization of MTP1, MTP8.1 and MTP9, and MTP11, respectively with QTLs/m-QTLs for Zn and Cd accumulation, making these genes promising candidates to understand the QTL regulation. Expression profiling of the entire set of 10 MTP genes revealed root and shoot specific expressions of MTP9 and MTP8.1, respectively, under all tested vegetative stages. Expression of seed-specific MTPs increased as seed maturation progressed, which revealed their potential role in transporting metals during seed filling. Upon exposure to harmful heavy metals, expression of most MTP genes decreased in root and increased in shoot, suggests that different mechanisms are being employed by MTPs in different tissues. Contrastingly, only a few MTPs were found to be responsive to Fe and/or Zn starvation conditions. The extensive analysis of MTPs presented here will be helpful in identifying candidate MTP genes for crop biofortification and bioremediation purposes.
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Affiliation(s)
- Hasthi Ram
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
| | - Amandeep Kaur
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
| | - Nishu Gandass
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
| | - Shweta Singh
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
| | - Rupesh Deshmukh
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
| | - Humira Sonah
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
| | - Tilak Raj Sharma
- Department of Agri-Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar(Mohali), Punjab, India
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Bernardi J, Battaglia R, Bagnaresi P, Lucini L, Marocco A. Transcriptomic and metabolomic analysis of ZmYUC1 mutant reveals the role of auxin during early endosperm formation in maize. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 281:133-145. [PMID: 30824046 DOI: 10.1016/j.plantsci.2019.01.027] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 01/22/2019] [Accepted: 01/30/2019] [Indexed: 05/22/2023]
Abstract
Kernel size in cereal is an important agronomic trait controlled by the interaction of genetic and environmental factors. The endosperm occupies most of the kernel area; for this reason, the endosperm cells dimension, number and metabolic content strongly influence kernel properties. This paper presents the transcriptomic and metabolomic analysis of the maize defective endosperm 18 (de18) mutant, where auxin accumulation in the endosperm is impaired. This mutation, involving the ZmYuc1 gene, leads to a reduced kernel size compared to the wild-type line B37. Our results mainly indicate that IAA concentration controls sugar and protein metabolism during kernel differentiation and it is necessary for BETL formation. Furthermore, a fine tuning of different auxin conjugates is reported as the main mechanism to counteract the auxin deficit. Some candidates as master regulators of endosperm transcriptional regulation mediated by auxin are found between MYB and MADS-box gene families. A link between auxin and storage protein accumulation is highlighted, suggesting that IAA directly or indirectly, through CK or ABA, regulates the transcription of zein coding genes. This study represents a move forward with respect to the current knowledge about the role of auxin during maize endosperm differentiation thus revealing the genes that are modulated by auxin and that control agronomic traits as kernel size and metabolic composition.
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Affiliation(s)
- Jamila Bernardi
- Department of Sustainable Crop Production, Università Cattolica del Sacro Cuore, Piacenza, Italy.
| | - Raffaella Battaglia
- Department of Sustainable Crop Production, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Paolo Bagnaresi
- Council for Agricultural Research and Economics, Research Centre for Genomics and Bioinformatics, Fiorenzuola d'Arda, Piacenza, Italy
| | - Luigi Lucini
- Department for Sustainable Food Process, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Adriano Marocco
- Department of Sustainable Crop Production, Università Cattolica del Sacro Cuore, Piacenza, Italy.
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Sosso D, van der Linde K, Bezrutczyk M, Schuler D, Schneider K, Kämper J, Walbot V. Sugar Partitioning between Ustilago maydis and Its Host Zea mays L during Infection. PLANT PHYSIOLOGY 2019; 179:1373-1385. [PMID: 30593452 PMCID: PMC6446792 DOI: 10.1104/pp.18.01435] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 12/10/2018] [Indexed: 05/20/2023]
Abstract
The basidiomycete Ustilago maydis causes smut disease in maize (Zea mays) by infecting all plant aerial tissues. The infection causes leaf chlorosis and stimulates the plant to produce nutrient-rich niches (i.e. tumors), where the fungus can proliferate and complete its life cycle. Previous studies have recorded high accumulation of soluble sugars and starch within these tumors. Using interdisciplinary approaches, we found that the sugar accumulation within tumors coincided with the differential expression of plant sugars will eventually be exported transporters and the proton/sucrose symporter Sucrose Transporter1 To accumulate plant sugars, the fungus deploys its own set of sugar transporters, generating a sugar gradient within the fungal cytosol, recorded by expressing a cytosolic glucose (Glc) Förster resonance energy transfer sensor. Our measurements indicated likely elevated Glc levels in hyphal tips during infection. Growing infected plants under dark conditions led to decreased plant sugar levels and loss of the fungal tip Glc gradient, supporting a tight link between fungal sugar acquisition and host supplies. Finally, the fungal infection causes a strong imbalance in plant sugar distribution, ultimately impacting seed set and yield.
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Affiliation(s)
- Davide Sosso
- Department of Plant Biology, Carnegie Science, Stanford, California 94305
- Department of Biology, Stanford University, Stanford, California 94305
| | | | - Margaret Bezrutczyk
- Department of Plant Biology, Carnegie Science, Stanford, California 94305
- Institute for Molecular Physiology, Heinrich Heine University, Duesseldorf 40225, Germany
| | - David Schuler
- Department of Genetics, Institute of Applied Biosciences, Karlsruhe Institute of Technology, Karlsruhe 76187, Germany
| | - Karina Schneider
- Department of Genetics, Institute of Applied Biosciences, Karlsruhe Institute of Technology, Karlsruhe 76187, Germany
| | - Jörg Kämper
- Department of Genetics, Institute of Applied Biosciences, Karlsruhe Institute of Technology, Karlsruhe 76187, Germany
| | - Virginia Walbot
- Department of Biology, Stanford University, Stanford, California 94305
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77
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Li Y, Zhang D, An N, Fan S, Zuo X, Zhang X, Zhang L, Gao C, Han M, Xing L. Transcriptomic analysis reveals the regulatory module of apple (Malus × domestica) floral transition in response to 6-BA. BMC PLANT BIOLOGY 2019; 19:93. [PMID: 30841918 PMCID: PMC6402183 DOI: 10.1186/s12870-019-1695-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 02/25/2019] [Indexed: 05/19/2023]
Abstract
BACKGROUND Insufficient production of flower buds is an intractable problem in 'Fuji' apple orchards. Although cytokinin (CK) promotes flower bud formation in apple trees, little is known about the mechanisms regulating this phenomenon. RESULTS In the present study, high-throughput RNA sequencing (RNA-Seq) of 'Nagafu No. 2' buds was conducted to characterize the transcriptional response to 6-BA treatment during key period of floral transition. A weighted gene co-expression network analysis (WGCNA) of the differentially expressed genes identified hormone signal transduction pathways, totaling 84 genes were highly correlated with the expression pattern of flowering-time genes. The up-regulation of CK signal components and a gibberellin (GA) signal repressor were found to contribute to the promotion of floral transition. In relative comparison to non-treated buds, a series of sugar metabolism- and signal- related genes were associated with relatively high levels of sucrose, fructose, and glucose during floral induction in the 6-BA treated buds. Several transcription factors (i.e. SPLs, SOC1, FD, and COL) that are involved in GA, aging, and photoperiod-regulated flowering pathways were also upregulated by the 6-BA treatment. In addition, potential transcription factors integrating CK signaling to trigger floral induction in apple were also assessed; including PHYTO-CHROME-INTERACTING FACTOR (PIF1,3), WUSCHEL-related homeobox (WOX3,13), and CK response regulators (ARR2). CONCLUSIONS The present study provides insight into the response of flowering and development-related pathways and transcription factors to 6-BA during the period of floral transition in apple. It extends our knowledge of the fundamental mechanisms associated with CK-regulated floral transition in apple trees.
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Affiliation(s)
- Youmei Li
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Dong Zhang
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Na An
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Sheng Fan
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Xiya Zuo
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Xin Zhang
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Lizhi Zhang
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Cai Gao
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Mingyu Han
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
| | - Libo Xing
- Department of Horticulture College, Northwest Agriculture & Forestry University, Yangling, 712100 China
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Figueiredo R, Araújo P, Llerena JPP, Mazzafera P. Suberin and hemicellulose in sugarcane cell wall architecture and crop digestibility: A biotechnological perspective. Food Energy Secur 2019. [DOI: 10.1002/fes3.163] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Raquel Figueiredo
- Department of Plant Biology Institute of Biology State University of Campinas Campinas Brazil
| | - Pedro Araújo
- Department of Genetics, Evolution and Bioagents Institute of Biology State University of Campinas Campinas Brazil
| | - Juan Pablo P. Llerena
- Department of Plant Biology Institute of Biology State University of Campinas Campinas Brazil
| | - Paulo Mazzafera
- Department of Plant Biology Institute of Biology State University of Campinas Campinas Brazil
- Department of Crop Science College of Agriculture Luiz de Queiroz University of São Paulo Piracicaba Brazil
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Handakumbura PP, Stanfill B, Rivas-Ubach A, Fortin D, Vogel JP, Jansson C. Metabotyping as a Stopover in Genome-to-Phenome Mapping. Sci Rep 2019; 9:1858. [PMID: 30755686 PMCID: PMC6372633 DOI: 10.1038/s41598-019-38483-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 12/21/2018] [Indexed: 01/01/2023] Open
Abstract
Predicting phenotypic expression from genomic and environmental information is arguably the greatest challenge in today's biology. Being able to survey genomic content, e.g., as single-nucleotide polymorphism data, within a diverse population and predict the phenotypes of external traits, represents the holy grail across genome-informed disciplines, from personal medicine and nutrition to plant breeding. In the present study, we propose a two-step procedure in bridging the genome to phenome gap where external phenotypes are viewed as emergent properties of internal phenotypes, such as molecular profiles, in interaction with the environment. Using biomass accumulation and shoot-root allometry as external traits in diverse genotypes of the model grass Brachypodium distachyon, we established correlative models between genotypes and metabolite profiles (metabotypes) as internal phenotypes, and between metabotypes and external phenotypes under two contrasting watering regimes. Our results demonstrate the potential for employing metabotypes as an integrator in predicting external phenotypes from genomic information.
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Affiliation(s)
- Pubudu P Handakumbura
- The Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory (PNNL), Washington, WA, 99352, USA.
| | - Bryan Stanfill
- Advanced Computing, Computing and Analytics Division, PNNL, Richland, WA, 99352, USA
| | - Albert Rivas-Ubach
- The Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory (PNNL), Washington, WA, 99352, USA
| | - Dan Fortin
- Advanced Computing, Computing and Analytics Division, PNNL, Richland, WA, 99352, USA
| | - John P Vogel
- US Department of Energy (DOE) Joint Genome Institute (JGI), Walnut Creek, CA, 94598, USA
| | - Christer Jansson
- The Environmental Molecular Sciences Laboratory (EMSL), Pacific Northwest National Laboratory (PNNL), Washington, WA, 99352, USA.
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80
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Sun X, Basnet RK, Yan Z, Bucher J, Cai C, Zhao J, Bonnema G. Genome-wide transcriptome analysis reveals molecular pathways involved in leafy head formation of Chinese cabbage ( Brassica rapa). HORTICULTURE RESEARCH 2019; 6:130. [PMID: 31814983 PMCID: PMC6885048 DOI: 10.1038/s41438-019-0212-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 09/21/2019] [Accepted: 10/19/2019] [Indexed: 05/10/2023]
Abstract
Chinese cabbage plants go through seedling and rosette stages before forming their leafy head. Chinese cabbage plants resemble pak-choi plants at their seedling stage, but in their rosette stage the leaves of Chinese cabbage differentiate, as they increase in size with shorter petioles. In order to understand the molecular pathways that play a role in leafy head formation, transcript abundance of young emerging leaves was profiled during development of two Chinese cabbage genotypes and a single pak-choi genotype. The two Chinese cabbages differed in many aspects, among others earliness, leaf size and shape, leaf numbers, and leafy head shape. Genome-wide transcriptome analysis clearly separated the seedling stages of all three genotypes together with the later stages from pak-choi, from the later developmental stages of both Chinese cabbages (rosette, folding, and heading). Weighted correlation network analysis and hierarchical clustering using Euclidean distances resulted in gene clusters with transcript abundance patterns distinguishing the two Chinese cabbages from pak-choi. Three clusters included genes with transcript abundance affected by both genotype and developmental stage, whereas two clusters showed only genotype effects. This included a genotype by developmental stage cluster highly enriched with the MapMan category photosynthesis, with high expression during rosette and folding in Chinese cabbages and low expression in the heading inner leaves that are not exposed to light. The other clusters contained many genes in the MapMan categories Cell, showing again differences between pak-choi and both Chinese cabbages. We discuss how this relates to the differences in leaf blade growth between Chinese cabbage and pak-choi, especially at the rosette stage. Overall, comparison of the transcriptome between leaves of two very different Chinese cabbages with pak-choi during plant development allowed the identification of specific gene categories associated with leafy head formation.
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Affiliation(s)
- XiaoXue Sun
- Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, Department of Horticulture, Hebei Agricultural University, Baoding, 071001 China
- Plant Breeding, Wageningen University and Research, Wageningen, 6708PB The Netherlands
| | - Ram Kumar Basnet
- Quantitative genetics department, Rijk Zwaan Breeding B.V., Eerste Kruisweg 9, Fijnaart, 4793 RS The Netherlands
| | - Zhichun Yan
- Plant Breeding, Wageningen University and Research, Wageningen, 6708PB The Netherlands
| | - Johan Bucher
- Plant Breeding, Wageningen University and Research, Wageningen, 6708PB The Netherlands
| | - Chengcheng Cai
- Plant Breeding, Wageningen University and Research, Wageningen, 6708PB The Netherlands
| | - Jianjun Zhao
- Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, Department of Horticulture, Hebei Agricultural University, Baoding, 071001 China
| | - Guusje Bonnema
- Key Laboratory of Vegetable Germplasm Innovation and Utilization of Hebei, Collaborative Innovation Center of Vegetable Industry in Hebei, Department of Horticulture, Hebei Agricultural University, Baoding, 071001 China
- Plant Breeding, Wageningen University and Research, Wageningen, 6708PB The Netherlands
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81
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Su T, Han M, Min J, Zhou H, Zhang Q, Zhao J, Fang Y. Functional Characterization of Invertase Inhibitors PtC/VIF1 and 2 Revealed Their Involvements in the Defense Response to Fungal Pathogen in Populus trichocarpa. FRONTIERS IN PLANT SCIENCE 2019; 10:1654. [PMID: 31969894 PMCID: PMC6960229 DOI: 10.3389/fpls.2019.01654] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 11/22/2019] [Indexed: 05/05/2023]
Abstract
In higher plants, cell wall invertase (CWI) and vacuolar invertase (VI) were considered to be essential coordinators in carbohydrate partitioning, sink strength determination, and stress responses. An increasing body of evidence revealed that the tight regulation of CWI and VI substantially depends on the post-translational mechanisms, which were mediated by small proteinaceous inhibitors (C/VIFs, Inhibitor of β-Fructosidases). As yet, the extensive survey of the molecular basis and biochemical property of C/VIFs remains largely unknown in black cottonwood (Populus trichocarpa Torr. & A. Gray), a model species of woody plants. In the present work, we have initiated a systematic review of the genomic structures, phylogenies, cis-regulatory elements, and conserved motifs as well as the tissue-specific expression, resulting in the identification of 39 genes encoding C/VIF in poplar genome. We characterized two putative invertase inhibitors PtC/VIF1 and 2, showing predominant transcript levels in the roots and highly divergent responses to the selected stress cues including fusarium wilt, drought, ABA, wound, and senescence. In silico prediction of the signal peptide hinted us that they both likely had the apoplastic targets. Based on the experimental visualization via the transient and stable transformation assays, we confirmed that PtC/VIF1 and 2 indeed secreted to the extracellular compartments. Further validation of their recombinant enzymes revealed that they displayed the potent inhibitory affinities on the extracted CWI, supporting the patterns that act as the typical apoplastic invertase inhibitors. To our knowledge, it is the first report on molecular characterization of the functional C/VIF proteins in poplar. Our results indicate that PtC/VIF1 and 2 may exert essential roles in defense- and stress-related responses. Moreover, novel findings of the up- and downregulated C/VIF genes and functional enzyme activities enable us to further unravel the molecular mechanisms in the promotion of woody plant performance and adapted-biotic stress, underlying the homeostatic control of sugar in the apoplast.
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Affiliation(s)
- Tao Su
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
- Key Laboratory of State Forestry Administration on Subtropical Forest Biodiversity Conservation, Nanjing Forestry University, Nanjing, China
| | - Mei Han
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
- *Correspondence: Mei Han, ;
| | - Jie Min
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
| | - Huaiye Zhou
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
| | - Qi Zhang
- College of Forest, Nanjing Forestry University, Nanjing, China
| | - Jingyi Zhao
- College of Forest, Nanjing Forestry University, Nanjing, China
| | - Yanming Fang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
- Key Laboratory of State Forestry Administration on Subtropical Forest Biodiversity Conservation, Nanjing Forestry University, Nanjing, China
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82
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Smith MR, Rao IM, Merchant A. Source-Sink Relationships in Crop Plants and Their Influence on Yield Development and Nutritional Quality. FRONTIERS IN PLANT SCIENCE 2018; 9:1889. [PMID: 30619435 PMCID: PMC6306447 DOI: 10.3389/fpls.2018.01889] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/06/2018] [Indexed: 05/02/2023]
Abstract
For seed crops, yield is the cumulative result of both source and sink strength for photoassimilates and nutrients over the course of seed development. Source strength for photoassimilates is dictated by both net photosynthetic rate and the rate of photoassimilate remobilisation from source tissues. This review focuses on the current understanding of how the source-sink relationship in crop plants influences rates of yield development and the resilience of yield and nutritional quality. We present the limitations of current approaches to accurately measure sink strength and emphasize differences in coordination between photosynthesis and yield under varying environmental conditions. We highlight the potential to exploit source-sink dynamics, in order to improve yields and emphasize the importance of resilience in yield and nutritional quality with implications for plant breeding strategies.
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Affiliation(s)
- Millicent R. Smith
- School of Life and Environmental Sciences, Faculty of Science, Sydney Institute of Agriculture, The University of Sydney, Sydney, NSW, Australia
| | | | - Andrew Merchant
- School of Life and Environmental Sciences, Faculty of Science, Sydney Institute of Agriculture, The University of Sydney, Sydney, NSW, Australia
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83
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Carbohydrate Dynamics in Maize Leaves and Developing Ears in Response to Nitrogen Application. AGRONOMY-BASEL 2018. [DOI: 10.3390/agronomy8120302] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Maize grain yield is considered to be highly associated with ear and leaf carbohydrate dynamics during the critical period bracketing silking and during the fast grain filling phase. However, a full understanding of how differences in N availability/plant N status influence carbohydrate dynamics and processes underlying yield formation remains elusive. Two field experiments were conducted to examine maize ear development, grain yield and the dynamics of carbohydrates in maize ear leaves and developing ears in response to differences in N availability. Increasing N availability stimulated ear growth during the critical two weeks bracketing silking and during the fast grain-filling phase, consequently resulting in greater maize grain yield. In ear leaves, sucrose and starch concentrations exhibited an obvious diurnal pattern at both silking and 20 days after silking, and N fertilization led to more carbon flux to sucrose biosynthesis than to starch accumulation. The elevated transcript abundance of key genes involved in starch biosynthesis and maltose export, as well as the sugar transporters (SWEETs) important for phloem loading, indicated greater starch turnover and sucrose export from leaves under N-fertilized conditions. In developing ears, N fertilization likely enhanced the cleavage of sucrose to glucose and fructose in the cob prior to and at silking and the synthesis from glucose and fructose to sucrose in the kernels after silking, and thus increasing kernel setting and filling. At the end, we propose a source-sink carbon partitioning framework to illustrates how N application influences carbon assimilation in leaves, transport, and conversions in developing reproductive tissues, ultimately leading to greater yield.
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84
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Morales L, Marino TP, Wenndt AJ, Fouts JQ, Holland JB, Nelson RJ. Dissecting Symptomatology and Fumonisin Contamination Produced by Fusarium verticillioides in Maize Ears. PHYTOPATHOLOGY 2018; 108:1475-1485. [PMID: 29989846 DOI: 10.1094/phyto-05-18-0167-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The fungus Fusarium verticillioides can infect maize ears, contaminating the grain with mycotoxins, including fumonisins. This global public health threat can be managed by breeding maize varieties that are resistant to colonization by F. verticillioides and by sorting grain after harvest to reduce fumonisin levels in food systems. Here, we employed two F. verticillioides inoculation techniques representing distinct infection pathways to dissect ear symptomatology and morphological resistance mechanisms in a diverse panel of maize inbred lines. The "point" method involved penetrating the ear with a spore-coated toothpick and the "inundative" method introduced a liquid spore suspension under the husk of the ear. We evaluated quantitative and qualitative indicators of external and internal symptom severity as low-cost proxies for fumonisin contamination, and found that kernel bulk density was predictive of fumonisin levels (78 to 84% sensitivity; 97 to 99% specificity). Inundative inoculation resulted in greater disease severity and fumonisin contamination than point inoculation. We also found that the two inoculation methods implicated different ear tissues in defense, with cob morphology being a more important component of resistance under point inoculation. Across both inoculation methods, traits related to cob size were positively associated with disease severity and fumonisin content. Our work demonstrates that (i) the use of diverse modes of inoculation is necessary for combining complementary mechanisms of genetic resistance, (ii) kernel bulk density can be used effectively as a proxy for fumonisin levels, and (iii) trade-offs may exist between yield potential and resistance to fumonisin contamination.
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Affiliation(s)
- Laura Morales
- First, third, fourth, and sixth authors: School of Integrative Plant Science, Cornell University, Ithaca, NY; second and fifth authors: Department of Crop and Soil Sciences, North Carolina State University, Raleigh; and fifth author: Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC
| | - Thiago P Marino
- First, third, fourth, and sixth authors: School of Integrative Plant Science, Cornell University, Ithaca, NY; second and fifth authors: Department of Crop and Soil Sciences, North Carolina State University, Raleigh; and fifth author: Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC
| | - Anthony J Wenndt
- First, third, fourth, and sixth authors: School of Integrative Plant Science, Cornell University, Ithaca, NY; second and fifth authors: Department of Crop and Soil Sciences, North Carolina State University, Raleigh; and fifth author: Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC
| | - Julia Q Fouts
- First, third, fourth, and sixth authors: School of Integrative Plant Science, Cornell University, Ithaca, NY; second and fifth authors: Department of Crop and Soil Sciences, North Carolina State University, Raleigh; and fifth author: Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC
| | - James B Holland
- First, third, fourth, and sixth authors: School of Integrative Plant Science, Cornell University, Ithaca, NY; second and fifth authors: Department of Crop and Soil Sciences, North Carolina State University, Raleigh; and fifth author: Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC
| | - Rebecca J Nelson
- First, third, fourth, and sixth authors: School of Integrative Plant Science, Cornell University, Ithaca, NY; second and fifth authors: Department of Crop and Soil Sciences, North Carolina State University, Raleigh; and fifth author: Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC
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85
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Yuan Y, Mei L, Wu M, Wei W, Shan W, Gong Z, Zhang Q, Yang F, Yan F, Zhang Q, Luo Y, Xu X, Zhang W, Miao M, Lu W, Li Z, Deng W. SlARF10, an auxin response factor, is involved in chlorophyll and sugar accumulation during tomato fruit development. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:5507-5518. [PMID: 30219898 PMCID: PMC6255703 DOI: 10.1093/jxb/ery328] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Indexed: 05/03/2023]
Abstract
The photosynthesis of green tomatoes contributes to fruit growth and carbon economy. The tomato auxin response factor 10 (SlARF10) belongs to the ARF family and is located in nucleus. In this study, we found that SlARF10 was highly expressed in green fruit. Overexpression of SlARF10 in fruit produced a dark-green phenotype whilst knock-down by RNAi produced a light-green phenotype. Autofluorescence and chlorophyll content analyses confirmed the phenotypes, which indicated that SlARF10 plays an important role in chlorophyll accumulation. Overexpression of SlARF10 positively affected photosynthesis in both leaves and fruit. Furthermore, SlARF10-overexpression lines displayed improved accumulation of starch, fructose, and sucrose in fruit, whilst SlARF10-RNAi lines showed decreased accumulation of starch and sucrose. Regulation of SlARF10 expression altered the expression of AGPase starch biosynthesis genes. SlARF10 positively regulated the expression of SlGLK1, POR, CBP1, and CBP2, which are related to chlorophyll metabolism and regulation. Electrophoretic mobility shift assays confirmed that SlARF10 directly targets to the SlGLK1 promoter. Our results thus indicate that SlARF10 is involved in chlorophyll accumulation by transcriptional activation of SlGLK1 expression in tomato fruit, and provide insights into the link between auxin signaling, chloroplast activity, and sugar metabolism during tomato fruit development.
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Affiliation(s)
- Yujin Yuan
- School of Life Science, Chongqing University, Chongqing, China
| | - Lihua Mei
- School of Life Science, Chongqing University, Chongqing, China
| | - Mengbo Wu
- School of Life Science, Chongqing University, Chongqing, China
| | - Wei Wei
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Wei Shan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Zehao Gong
- School of Life Science, Chongqing University, Chongqing, China
| | - Qian Zhang
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, China
| | - Fengqing Yang
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, China
| | - Fang Yan
- School of Life Science, Chongqing University, Chongqing, China
| | - Qiang Zhang
- School of Life Science, Chongqing University, Chongqing, China
| | - Yingqing Luo
- School of Life Science, Chongqing University, Chongqing, China
| | - Xin Xu
- School of Life Science, Chongqing University, Chongqing, China
| | - Wenfa Zhang
- School of Life Science, Chongqing University, Chongqing, China
| | - Mingjun Miao
- Horticulture Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Wangjin Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables, College of Horticulture, South China Agricultural University, Guangzhou, China
| | - Zhengguo Li
- School of Life Science, Chongqing University, Chongqing, China
| | - Wei Deng
- School of Life Science, Chongqing University, Chongqing, China
- Correspondence:
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86
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Casto AL, McKinley BA, Yu KMJ, Rooney WL, Mullet JE. Sorghum stem aerenchyma formation is regulated by SbNAC_D during internode development. PLANT DIRECT 2018; 2:e00085. [PMID: 31245693 PMCID: PMC6508845 DOI: 10.1002/pld3.85] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 09/12/2018] [Indexed: 05/10/2023]
Abstract
Sorghum bicolor is a drought-resilient C4 grass used for production of grain, forage, sugar, and biomass. Sorghum genotypes capable of accumulating high levels of stem sucrose have solid stems that contain low levels of aerenchyma. The D-locus on SBI06 modulates the extent of aerenchyma formation in sorghum stems and leaf midribs. A QTL aligned with this locus was identified and fine-mapped in populations derived from BTx623*IS320c, BTx623*R07007, and BTx623*Standard broomcorn. Analysis of coding polymorphisms in the fine-mapped D-locus showed that genotypes that accumulate low levels of aerenchyma encode a truncated NAC transcription factor (Sobic.006G147400, SbNAC_d1), whereas parental lines that accumulate higher levels of stem aerenchyma encode full-length NAC TFs (SbNAC-D). During vegetative stem development, aerenchyma levels are low in nonelongated stem internodes, internode growing zones, and nodes. Aerenchyma levels increase in recently elongated internodes starting at the top of the internode near the center of the stem. SbNAC_D was expressed at low levels in nonelongated internodes and internode growing zones and at higher levels in regions of stem internodes that form aerenchyma. SbXCP1, a gene encoding a cysteine protease involved in programmed cell death, was induced in SbNAC_D genotypes in parallel with aerenchyma formation in sorghum stems but not in SbNAC_d1 genotypes. Several sweet sorghum genotypes encode the recessive SbNAC_d1 allele and have low levels of stem aerenchyma. Based on these results, we propose that SbNAC_D is the D-gene identified by Hilton (1916) and that allelic variation in SbNAC_D modulates the extent of aerenchyma formation in sorghum stems.
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Affiliation(s)
- Anna L. Casto
- Department of Biochemistry and BiophysicsTexas A&M UniversityCollege StationTexas
- Molecular and Environmental Plant Sciences Graduate ProgramTexas A&M UniversityCollege StationTexas
| | - Brian A. McKinley
- Department of Biochemistry and BiophysicsTexas A&M UniversityCollege StationTexas
| | - Ka Man Jasmine Yu
- Department of Biochemistry and BiophysicsTexas A&M UniversityCollege StationTexas
- Biochemistry and Biophysics Graduate ProgramTexas A&M UniversityCollege StationTexas
| | - William L. Rooney
- Department of Soil and Crop SciencesTexas A&M UniversityCollege StationTexas
| | - John E. Mullet
- Department of Biochemistry and BiophysicsTexas A&M UniversityCollege StationTexas
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87
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Allele-defined genome of the autopolyploid sugarcane Saccharum spontaneum L. Nat Genet 2018; 50:1565-1573. [DOI: 10.1038/s41588-018-0237-2] [Citation(s) in RCA: 288] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 08/15/2018] [Indexed: 01/13/2023]
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88
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Aguirre M, Kiegle E, Leo G, Ezquer I. Carbohydrate reserves and seed development: an overview. PLANT REPRODUCTION 2018; 31:263-290. [PMID: 29728792 DOI: 10.1007/s00497-018-0336-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Seeds are one of the most important food sources, providing humans and animals with essential nutrients. These nutrients include carbohydrates, lipids, proteins, vitamins and minerals. Carbohydrates are one of the main energy sources for both plant and animal cells and play a fundamental role in seed development, human nutrition and the food industry. Many studies have focused on the molecular pathways that control carbohydrate flow during seed development in monocot and dicot species. For this reason, an overview of seed biodiversity focused on the multiple metabolic and physiological mechanisms that govern seed carbohydrate storage function in the plant kingdom is required. A large number of mutants affecting carbohydrate metabolism, which display defective seed development, are currently available for many plant species. The physiological, biochemical and biomolecular study of such mutants has led researchers to understand better how metabolism of carbohydrates works in plants and the critical role that these carbohydrates, and especially starch, play during seed development. In this review, we summarize and analyze the newest findings related to carbohydrate metabolism's effects on seed development, pointing out key regulatory genes and enzymes that influence seed sugar import and metabolism. Our review also aims to provide guidelines for future research in the field and in this way to assist seed quality optimization by targeted genetic engineering and classical breeding programs.
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Affiliation(s)
- Manuel Aguirre
- Dipartimento di BioScienze, Università degli Studi di Milano, 20133, Milan, Italy
- FNWI, University of Amsterdam, 1098 XH, Amsterdam, The Netherlands
| | - Edward Kiegle
- Dipartimento di BioScienze, Università degli Studi di Milano, 20133, Milan, Italy
| | - Giulia Leo
- Dipartimento di BioScienze, Università degli Studi di Milano, 20133, Milan, Italy
| | - Ignacio Ezquer
- Dipartimento di BioScienze, Università degli Studi di Milano, 20133, Milan, Italy.
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89
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Chen G, Zhang Y, Ruan B, Guo L, Zeng D, Gao Z, Zhu L, Hu J, Ren D, Yu L, Xu G, Qian Q. OsHAK1 controls the vegetative growth and panicle fertility of rice by its effect on potassium-mediated sugar metabolism. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 274:261-270. [PMID: 30080612 DOI: 10.1016/j.plantsci.2018.05.034] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/21/2018] [Accepted: 05/31/2018] [Indexed: 05/26/2023]
Abstract
Plant growth and reproduction are both energy-requiring processes; the necessary energy is supplied by the products of photosynthesis. Both the vegetative growth and reproductive success of rice are compromised by the absence of a functional copy of the gene OsHAK1. Here, a comparison between wild type rice and OsHAK1 knockout mutants not only confirmed the known detrimental effect of the absence of OsHAK1 on root growth, pollen viability and fertility, but also showed that sucrose phosphate synthase activity was lowered, and the sucrose content of the leaves was markedly increased, due to a partial block on the up-loading of sucrose into the phloem. The impaired allocation of sugar to the roots and spikelets caused by the knocking out of OsHAK1 was accompanied by a down-regulation in the leaf sheaths and panicle axes of genes encoding sucrose transporters (SUT genes), which are active in the phloem, as well as in the roots and spikelets of those encoding monosaccharide transporters (MST genes), which transport hexose sugars across the plant plasma membrane. The activity of sucrose synthase, acid invertase and neutral invertase in the roots of mutant plants assayed at the tillering stage, and in their spikelets, assayed during grain-filling, was significantly lower than in the equivalent organs of wild type plants. As a result, the supply of total soluble sugar, glucose and fructose to sink organs was reduced, consistent with the effect of the mutation on root growth and panicle fertility. Compared to wild type plants, the mutants accumulated less potassium (K) throughout the plant. The conclusion was that the failure to fully supply the demand of the mutant's sink organs for assimilate was responsible for its compromised phenotype, and that the deficiency in K uptake induced by the loss of OsHAK1 functionality was responsible for the disruption of sugar metabolism.
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Affiliation(s)
- Guang Chen
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China; State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China.
| | - Yu Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Banpu Ruan
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Longbiao Guo
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Dali Zeng
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Zhenyu Gao
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Li Zhu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Jiang Hu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Deyong Ren
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China
| | - Ling Yu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing Agricultural University, Nanjing 210095, PR China.
| | - Qian Qian
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, PR China.
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90
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Hanson AD, Amthor JS, Sun J, Niehaus TD, Gregory JF, Bruner SD, Ding Y. Redesigning thiamin synthesis: Prospects and potential payoffs. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 273:92-99. [PMID: 29907313 DOI: 10.1016/j.plantsci.2018.01.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 01/24/2018] [Accepted: 01/31/2018] [Indexed: 05/20/2023]
Abstract
Thiamin is essential for plant growth but is short-lived in vivo and energetically very costly to produce - a combination that makes thiamin biosynthesis a prime target for improvement by redesign. Thiamin consists of thiazole and pyrimidine moieties. Its high biosynthetic cost stems from use of the suicide enzyme THI4 to form the thiazole and the near-suicide enzyme THIC to form the pyrimidine. These energetic costs lower biomass yield potential and are likely compounded by environmental stresses that destroy thiamin and hence increase the rate at which it must be made. The energy costs could be slashed by refactoring the thiamin biosynthesis pathway to eliminate the suicidal THI4 and THIC reactions. To substantiate this design concept, we first document the energetic costs of the THI4 and THIC steps in the pathway and explain how cutting these costs could substantially increase crop biomass and grain yields. We then show that a refactored pathway must produce thiamin itself rather than a stripped-down analog because the thiamin molecule cannot be simplified without losing biological activity. Lastly, we consider possible energy-efficient alternatives to the inefficient natural THI4- and THIC-mediated steps.
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Affiliation(s)
- Andrew D Hanson
- Horticultural Sciences Department, University of Florida, Gainesville, FL, USA.
| | | | - Jiayi Sun
- Horticultural Sciences Department, University of Florida, Gainesville, FL, USA
| | - Thomas D Niehaus
- Horticultural Sciences Department, University of Florida, Gainesville, FL, USA
| | - Jesse F Gregory
- Food Science and Human Nutrition Department, University of Florida, Gainesville, FL, USA
| | - Steven D Bruner
- Chemistry Department, University of Florida, Gainesville, FL, USA
| | - Yousong Ding
- Department of Medicinal Chemistry, University of Florida, Gainesville, FL, USA
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91
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Jansson C, Vogel J, Hazen S, Brutnell T, Mockler T. Climate-smart crops with enhanced photosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:3801-3809. [PMID: 30032188 DOI: 10.1093/jxb/ery213] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/29/2018] [Indexed: 05/20/2023]
Abstract
The potential of enhanced photosynthetic efficiency to help achieve the sustainable yield increases required to meet future demands for food and energy has spurred intense research towards understanding, modeling, and engineering photosynthesis. These current efforts, largely focused on the C3 model Arabidopsis thaliana or crop plants (e.g. rice, sorghum, maize, and wheat), could be intensified and broadened using model systems closely related to our food, feed, and energy crops and that allow rapid design-build-test-learn cycles. In this outlooking Opinion, we advocate for a concerted effort to expand our understanding and improve our ability to redesign carbon uptake, allocation, and utilization. We propose two specific research directions that combine enhanced photosynthesis with climate-smart metabolic attributes: (i) engineering pathways for flexible (facultative) C3-C4 metabolism where plants will operate either C3 or C4 photosynthesis based on environmental conditions such as temperature, light, and atmospheric CO2 levels; and (ii) increasing rhizospheric sink strength for carbon utilization, including strategies that allow for augmented transport of carbon to the soil for improved soil properties and carbon storage without jeopardizing aboveground crop biomass. We argue that such ambitious undertakings be first approached and demonstrated by exploring the full genomic potential of two model grasses, the C3Brachypodium distachyon and the C4Setaria viridis. The development of climate-smart crops could provide novel and bold solutions to increase crop productivity while reducing atmospheric carbon and nitrogen emissions.
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Affiliation(s)
- Christer Jansson
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - John Vogel
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Walnut Creek CA, USA
| | - Samuel Hazen
- Biology Department, University of Massachusetts, Amherst, MA, USA
| | | | - Todd Mockler
- Donald Danforth Plant Science Center, St. Louis, MO, USA
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Meuriot F, Morvan-Bertrand A, Noiraud-Romy N, Decau ML, Escobar-Gutiérrez AJ, Gastal F, Prud’homme MP. Short-term effects of defoliation intensity on sugar remobilization and N fluxes in ryegrass. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:3975-3986. [PMID: 29931373 PMCID: PMC6054246 DOI: 10.1093/jxb/ery211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 06/15/2018] [Indexed: 05/14/2023]
Abstract
In grassland plant communities, the ability of individual plants to regrow after defoliation is of crucial importance since it allows the restoration of active photosynthesis and plant growth. The aim of this study was to evaluate the effects of increasing defoliation intensity (0, 25, 65, 84, and 100% of removed leaf area) on sugar remobilization and N uptake, remobilization, and allocation in roots, adult leaves, and growing leaves of ryegrass over 2 days, using a 15N tracer technique. Increasing defoliation intensity decreased plant N uptake in a correlative way and increased plant N remobilization, but independently. The relative contribution of N stored before defoliation to leaf growth increased when defoliation intensity was severe. In most conditions, root N reserves also contributed to leaf regrowth, but much less than adult leaves and irrespective of defoliation intensity. A threshold of defoliation intensity (65% leaf area removal) was identified below which C (glucose, fructose, sucrose, fructans), and N (amino acids, soluble proteins) storage compounds were not recruited for regrowth. By contrast, nitrate content increased in elongating leaf bases above this threshold. Wounding associated with defoliation is thus not the predominant signal that triggers storage remobilization and controls the priority of resource allocation to leaf meristems. A framework integrating the sequential events leading to the refoliation of grasses is proposed on the basis of current knowledge and on the findings of the present work.
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Affiliation(s)
- Frédéric Meuriot
- Université de Caen Normandie, INRA, UMR 950, Ecophysiologie Végétale, Agronomie et Nutritions NCS, Caen, France
| | - Annette Morvan-Bertrand
- Université de Caen Normandie, INRA, UMR 950, Ecophysiologie Végétale, Agronomie et Nutritions NCS, Caen, France
| | - Nathalie Noiraud-Romy
- Université de Caen Normandie, INRA, UMR 950, Ecophysiologie Végétale, Agronomie et Nutritions NCS, Caen, France
| | - Marie-Laure Decau
- Université de Caen Normandie, INRA, UMR 950, Ecophysiologie Végétale, Agronomie et Nutritions NCS, Caen, France
| | | | | | - Marie-Pascale Prud’homme
- Université de Caen Normandie, INRA, UMR 950, Ecophysiologie Végétale, Agronomie et Nutritions NCS, Caen, France
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93
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Juárez-Colunga S, López-González C, Morales-Elías NC, Massange-Sánchez JA, Trachsel S, Tiessen A. Genome-wide analysis of the invertase gene family from maize. PLANT MOLECULAR BIOLOGY 2018; 97:385-406. [PMID: 29948658 DOI: 10.1007/s11103-018-0746-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 06/04/2018] [Indexed: 05/14/2023]
Abstract
The recent release of the maize genome (AGPv4) contains annotation errors of invertase genes and therefore the enzymes are bestly curated manually at the protein level in a comprehensible fashion The synthesis, transport and degradation of sucrose are determining factors for biomass allocation and yield of crop plants. Invertase (INV) is a key enzyme of carbon metabolism in both source and sink tissues. Current releases of the maize genome correctly annotates only two vacuolar invertases (ivr1 and ivr2) and four cell wall invertases (incw1, incw2 (mn1), incw3, and incw4). Our comprehensive survey identified 21 INV isogenes for which we propose a standard nomenclature grouped phylogenetically by amino acid similarity: three vacuolar (INVVR), eight cell wall (INVCW), and ten alkaline/neutral (INVAN) isogenes which form separate dendogram branches due to distinct molecular features. The acidic enzymes were curated for the presence of the DPN tripeptide which is coded by one of the smallest exons reported in plants. Particular attention was placed on the molecular role of INV in vascular tissues such as the nodes, internodes, leaf sheath, husk leaves and roots. We report the expression profile of most members of the maize INV family in nine tissues in two developmental stages, R1 and R3. INVCW7, INVVR2, INVAN8, INVAN9, INVAN10, and INVAN3 displayed the highest absolute expressions in most tissues. INVVR3, INVCW5, INVCW8, and INVAN1 showed low mRNA levels. Expressions of most INVs were repressed from stage R1 to R3, except for INVCW7 which increased significantly in all tissues after flowering. The mRNA levels of INVCW7 in the vegetative stem correlated with a higher transport rate of assimilates from leaves to the cob which led to starch accumulation and growth of the female reproductive organs.
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Affiliation(s)
- Sheila Juárez-Colunga
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Km 9.6 Libramiento Norte, Irapuato, C.P. 36824, Guanajuato, Mexico
| | - Cristal López-González
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Km 9.6 Libramiento Norte, Irapuato, C.P. 36824, Guanajuato, Mexico
| | - Norma Cecilia Morales-Elías
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Km 9.6 Libramiento Norte, Irapuato, C.P. 36824, Guanajuato, Mexico
| | - Julio Armando Massange-Sánchez
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Km 9.6 Libramiento Norte, Irapuato, C.P. 36824, Guanajuato, Mexico
- KWS Group, Grimsehlstrasse 31, 37574, Einbeck, Germany
| | - Samuel Trachsel
- Global Maize Program, Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT), Km 45 Carretera Mexico-Veracruz, El Batán, 56130, Texcoco, State Of Mexico, Mexico
- Department of Genetics and Biotechnology, Aarhus University, Forsøgsvej 1, 4200, Slagelse, Denmark
| | - Axel Tiessen
- Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Km 9.6 Libramiento Norte, Irapuato, C.P. 36824, Guanajuato, Mexico.
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94
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Xia J, Zhao Y, Burks P, Pauly M, Brown PJ. A sorghum NAC gene is associated with variation in biomass properties and yield potential. PLANT DIRECT 2018; 2:e00070. [PMID: 31245734 PMCID: PMC6508854 DOI: 10.1002/pld3.70] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/12/2018] [Accepted: 06/19/2018] [Indexed: 05/13/2023]
Abstract
Sorghum bicolor is a C4 grass widely cultivated for grain, forage, sugar, and biomass. The sorghum Dry Stalk (D) locus controls a qualitative difference between juicy green (dd) and dry white (D-) stalks and midribs, and co-localizes with a quantitative trait locus for sugar yield. Here, we apply fine-mapping and genome-wide association study (GWAS) to identify a candidate gene underlying D, and use nearly isogenic lines (NILs) to characterize the transcriptional, compositional, and agronomic effects of variation at the D locus. The D locus was fine-mapped to a 36 kb interval containing four genes. One of these genes is a NAC transcription factor that contains a stop codon in the NAC domain in the recessive (dd) parent. Allelic variation at D affects grain yield, sugar yield, and biomass composition in NILs. Green midrib (dd) NILs show reductions in lignin in stalk tissue and produce higher sugar and grain yields under well-watered field conditions. Increased yield potential in dd NILs is associated with increased stalk mass and moisture, higher biomass digestibility, and an extended period of grain filling. Transcriptome profiling of midrib tissue at the 4-6 leaf stages, when NILs first become phenotypically distinct, reveals that dd NILs have increased expression of a miniature zinc finger (MIF) gene. MIF genes dimerize with and suppress zinc finger homeodomain (ZF-HD) transcription factors, and a ZF-HD gene is associated with midrib color variation in a GWAS analysis across 1,694 diverse sorghum inbreds. A premature stop codon in a NAC gene is the most likely candidate polymorphism underlying the sorghum D locus. More detailed understanding of the sorghum D locus could help improve agronomic potential in cereals.
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Affiliation(s)
- Jingnu Xia
- Department of Crop SciencesUniversity of Illinois at Urbana ChampaignUrbanaIllinois
- Present address:
Department of BiochemistryUniversity of OxfordOxfordUK
| | - Yunjun Zhao
- Department of Plant and Microbial BiologyUniversity of California, BerkeleyBerkeleyCalifornia
- Present address:
Brookhaven National LabUptonNew York
| | - Payne Burks
- Department of Crop SciencesUniversity of Illinois at Urbana ChampaignUrbanaIllinois
- Present address:
Chromatin Inc.LubbockTexas
| | - Markus Pauly
- Department of Plant and Microbial BiologyUniversity of California, BerkeleyBerkeleyCalifornia
- Present address:
Heinrich‐Heine UniversityDuesseldorfGermany
| | - Patrick J. Brown
- Department of Crop SciencesUniversity of Illinois at Urbana ChampaignUrbanaIllinois
- Present address:
University of California, DavisDavisCalifornia
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95
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96
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Cho H, Cho HS, Nam H, Jo H, Yoon J, Park C, Dang TVT, Kim E, Jeong J, Park S, Wallner ES, Youn H, Park J, Jeon J, Ryu H, Greb T, Choi K, Lee Y, Jang SK, Ban C, Hwang I. Translational control of phloem development by RNA G-quadruplex-JULGI determines plant sink strength. NATURE PLANTS 2018; 4:376-390. [PMID: 29808026 DOI: 10.1038/s41477-018-0157-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 04/19/2018] [Indexed: 05/24/2023]
Abstract
The emergence of a plant vascular system was a prerequisite for the colonization of land; however, it is unclear how the photosynthate transporting system was established during plant evolution. Here, we identify a novel translational regulatory module for phloem development involving the zinc-finger protein JULGI (JUL) and its targets, the 5' untranslated regions (UTRs) of the SUPPRESSOR OF MAX2 1-LIKE4/5 (SMXL4/5) mRNAs, which is exclusively conserved in vascular plants. JUL directly binds and induces an RNA G-quadruplex in the 5' UTR of SMXL4/5, which are key promoters of phloem differentiation. We show that RNA G-quadruplex formation suppresses SMXL4/5 translation and restricts phloem differentiation. In turn, JUL deficiency promotes phloem formation and strikingly increases sink strength per seed. We propose that the translational regulation by the JUL/5' UTR G-quadruplex module is a major determinant of phloem establishment, thereby determining carbon allocation to sink tissues, and that this mechanism was a key invention during the emergence of vascular plants.
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Affiliation(s)
- Hyunwoo Cho
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
| | - Hyun Seob Cho
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Hoyoung Nam
- Division of Integrative Bioscience and Biotechnology, Pohang University of Science and Technology, Pohang, Korea
| | - Hunho Jo
- Department of Chemistry, Pohang University of Science and Technology, Pohang, Korea
| | - Joonseon Yoon
- Crop Seed Development Team, Seed Business Division, FarmHannong Co. Ltd., Daejeon, Korea
| | - Chanyoung Park
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Tuong Vi T Dang
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Eunah Kim
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
- Division of Integrative Bioscience and Biotechnology, Pohang University of Science and Technology, Pohang, Korea
| | - Jongmin Jeong
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Soyoung Park
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Eva-Sophie Wallner
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
| | - Hyungjun Youn
- Department of Chemistry, Pohang University of Science and Technology, Pohang, Korea
| | - Jongmin Park
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Jinseong Jeon
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Hojin Ryu
- Department of Biology, Chungbuk National University, Cheongju, Korea
| | - Thomas Greb
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
| | - Kyuha Choi
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
| | - Yoontae Lee
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
- Division of Integrative Bioscience and Biotechnology, Pohang University of Science and Technology, Pohang, Korea
| | - Sung Key Jang
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea
- Division of Integrative Bioscience and Biotechnology, Pohang University of Science and Technology, Pohang, Korea
| | - Changill Ban
- Department of Chemistry, Pohang University of Science and Technology, Pohang, Korea
| | - Ildoo Hwang
- Department of Life Sciences, POSTECH Biotech Center, Pohang University of Science and Technology, Pohang, Korea.
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97
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Moreno-Pachon NM, Mutimawurugo MC, Heynen E, Sergeeva L, Benders A, Blilou I, Hilhorst HWM, Immink RGH. Role of Tulipa gesneriana TEOSINTE BRANCHED1 (TgTB1) in the control of axillary bud outgrowth in bulbs. PLANT REPRODUCTION 2018; 31:145-157. [PMID: 29218597 PMCID: PMC5940712 DOI: 10.1007/s00497-017-0316-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/01/2017] [Indexed: 05/05/2023]
Abstract
Tulip vegetative reproduction. Tulips reproduce asexually by the outgrowth of their axillary meristems located in the axil of each bulb scale. The number of axillary meristems in one bulb is low, and not all of them grow out during the yearly growth cycle of the bulb. Since the degree of axillary bud outgrowth in tulip determines the success of their vegetative propagation, this study aimed at understanding the mechanism controlling the differential axillary bud activity. We used a combined physiological and "bottom-up" molecular approach to shed light on this process and found that first two inner located buds do not seem to experience dormancy during the growth cycle, while mid-located buds enter dormancy by the end of the growing season. Dormancy was assessed by weight increase and TgTB1 expression levels, a conserved TCP transcription factor and well-known master integrator of environmental and endogenous signals influencing axillary meristem outgrowth in plants. We showed that TgTB1 expression in tulip bulbs can be modulated by sucrose, cytokinin and strigolactone, just as it has been reported for other species. However, the limited growth of mid-located buds, even when their TgTB1 expression is downregulated, points at other factors, probably physical, inhibiting their growth. We conclude that the time of axillary bud initiation determines the degree of dormancy and the sink strength of the bud. Thus, development, apical dominance, sink strength, hormonal cross-talk, expression of TgTB1 and other possibly physical but unidentified players, all converge to determine the growth capacity of tulip axillary buds.
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Affiliation(s)
- Natalia M Moreno-Pachon
- Physiology of Flower Bulbs, Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Marie-Chantal Mutimawurugo
- Physiology of Flower Bulbs, Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands
- Department of Crop Science, College of Agriculture, Animal Science and Veterinary Medicine, University of Rwanda, Musanze, Rwanda
| | - Eveline Heynen
- Physiology of Flower Bulbs, Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Lidiya Sergeeva
- Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Anne Benders
- Physiology of Flower Bulbs, Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Ikram Blilou
- Department of Plant Developmental Biology, Wageningen University and Research, Wageningen, The Netherlands
| | - Henk W M Hilhorst
- Wageningen Seed Laboratory (WSL), Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands
| | - Richard G H Immink
- Physiology of Flower Bulbs, Laboratory of Plant Physiology, Wageningen University and Research, Wageningen, The Netherlands.
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99
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Petridis A, van der Kaay J, Chrysanthou E, McCallum S, Graham J, Hancock RD. Photosynthetic limitation as a factor influencing yield in highbush blueberries (Vaccinium corymbosum) grown in a northern European environment. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:3069-3080. [PMID: 29590429 PMCID: PMC5972668 DOI: 10.1093/jxb/ery118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 03/21/2018] [Indexed: 05/20/2023]
Abstract
Published evidence indicates that nearly 60% of blueberry-producing countries experience yield instability. Yield is a complex trait determined by genetic and environmental factors. Here, using physiological and biochemical approaches, we tested the hypothesis that yield instability results from year-to-year environmental variation that limits carbon assimilation, storage and partitioning. The data indicate that fruit development depends primarily on the daily production of non-structural carbohydrates by leaves, and there is no accumulation of a starch buffer to allow continuous ripening under conditions limiting for photosynthesis. Photosynthesis was saturated at moderate light irradiance and this was mainly due to stomatal and biochemical limitations. In a dynamic light environment, photosynthesis was further limited by slow stomatal response to increasing light. Finally, labelling with 13CO2 at specific stages of fruit development revealed a relatively even distribution of newly assimilated carbon between stems, roots and fruits, suggesting that the fruit is not a strong sink. We conclude that a significant component of yield variability results from limitations in photosynthetic efficiency that are compounded by an inability to accumulate starch reserves in blueberry storage tissues in a typical northern European environment. This work informs techniques for improving agronomic management and indicates key traits required for yield stability in such environments.
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Affiliation(s)
- Antonios Petridis
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, UK
| | - Jeroen van der Kaay
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, UK
| | - Elina Chrysanthou
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, UK
| | - Susan McCallum
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, UK
| | - Julie Graham
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, UK
| | - Robert D Hancock
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, UK
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100
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Babst BA, Coleman GD. Seasonal nitrogen cycling in temperate trees: Transport and regulatory mechanisms are key missing links. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 270:268-277. [PMID: 29576080 DOI: 10.1016/j.plantsci.2018.02.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 02/22/2018] [Indexed: 05/08/2023]
Abstract
Nutrient accumulation, one of the major ecosystem services provided by forests, is largely due to the accumulation and retention of nutrients in trees. This review focuses on seasonal cycling of nitrogen (N), often the most limiting nutrient in terrestrial ecosystems. When leaves are shed during autumn, much of the N may be resorbed and stored in the stem over winter, and then used for new stem and leaf growth in spring. A framework exists for understanding the metabolism and transport of N in leaves and stems during winter dormancy, but many of the underlying genes remain to be identified and/or verified. Transport of N during seasonal N cycling is a particularly weak link, since the physical pathways for loading and unloading of amino N to and from the phloem are poorly understood. Short-day photoperiod followed by decreasing temperatures are the environmental cues that stimulate dormancy induction, and nutrient remobilization and storage. However, beyond the involvement of phytochrome, very little is known about the signal transduction mechanisms that link environmental cues to nutrient remobilization and storage. We propose a model whereby nutrient transport and sensing plays a major role in source-sink transitions of leaves and stems during seasonal N cycling.
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Affiliation(s)
- Benjamin A Babst
- Arkansas Forest Resources Center, Division of Agriculture, University of Arkansas System, Monticello, AR 71656, USA; School of Forestry and Natural Resources, University of Arkansas at Monticello, Monticello, AR 71656, USA.
| | - Gary D Coleman
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA.
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