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Xiong H, Luo Y, Zhao H, Wang J, Hu B, Yan C, Yao T, Zhang Y, Shi X, Rennenberg H. Integrated proteome and physiological traits reveal interactive mechanisms of new leaf growth and storage protein degradation with mature leaves of evergreen citrus trees. TREE PHYSIOLOGY 2024; 44:tpae001. [PMID: 38195893 DOI: 10.1093/treephys/tpae001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 12/29/2023] [Indexed: 01/11/2024]
Abstract
The growth of fruit trees depends on the nitrogen (N) remobilization in mature tissues and N acquisition from the soil. However, in evergreen mature citrus (Citrus reticulata Blanco) leaves, proteins with N storage functions and hub molecules involved in driving N remobilization remain largely unknown. Here, we combined proteome and physiological analyses to characterize the spatiotemporal mechanisms of growth of new leaves and storage protein degradation in mature leaves of citrus trees exposed to low-N and high-N fertilization in the field. Results show that the growth of new leaves is driven by remobilization of stored reserves, rather than N uptake by the roots. In this context, proline and arginine in mature leaves acted as N sources supporting the growth of new leaves in spring. Time-series analyses with gel electrophoresis and proteome analysis indicated that the mature autumn shoot leaves are probably the sites of storage protein synthesis, while the aspartic endopeptidase protein is related to the degradation of storage proteins in mature citrus leaves. Furthermore, bioinformatic analysis based on protein-protein interactions indicated that glutamate synthetase and ATP-citrate synthetase are hub proteins in N remobilization from mature citrus leaves. These results provide strong physiological data for seasonal optimization of N fertilizer application in citrus orchards.
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Affiliation(s)
- Huaye Xiong
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Yayin Luo
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Huanyu Zhao
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Jie Wang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Bin Hu
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Chengquan Yan
- Citrus Research Institute, Southwest University, Xiema, Beibei District, 400712 Chongqing, P.R. China
| | - Tingshan Yao
- Citrus Research Institute, Southwest University, Xiema, Beibei District, 400712 Chongqing, P.R. China
| | - Yueqiang Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Xiaojun Shi
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
| | - Heinz Rennenberg
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, No. 2, Tiansheng Road, Beibei District, 400715 Chongqing, P.R. China
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
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Xiong H, Ma H, Zhao H, Yang L, Hu B, Wang J, Shi X, Zhang Y, Rennenberg H. Integrated physiological, proteome and gene expression analyses provide new insights into nitrogen remobilization in citrus trees. TREE PHYSIOLOGY 2022; 42:1628-1645. [PMID: 35225347 DOI: 10.1093/treephys/tpac024] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Nitrogen (N) remobilization is an important physiological process that supports the growth and development of trees. However, in evergreen broad-leaved tree species, such as citrus, the mechanisms of N remobilization are not completely understood. Therefore, we quantified the potential of N remobilization from senescing leaves of spring shoots to mature leaves of autumn shoots of citrus trees under different soil N availabilities and further explored the underlying N metabolism characteristics by physiological, proteome and gene expression analyses. Citrus exposed to low N had an approximately 38% N remobilization efficiency (NRE), whereas citrus exposed to high N had an NRE efficiency of only 4.8%. Integrated physiological, proteomic and gene expression analyses showed that photosynthesis, N and carbohydrate metabolism interact with N remobilization. The improvement of N metabolism and photosynthesis, the accumulation of proline and arginine, and delayed degradation of storage protein in senescing leaves are the result of sufficient N supply and low N remobilization. Proteome further showed that energy generation proteins and glutamate synthase were hub proteins affecting N remobilization. In addition, N requirement of mature leaves is likely met by soil supply at high N nutrition, thereby resulting in low N remobilization. These results provide insight into N remobilization mechanisms of citrus that are of significance for N fertilizer management in orchards.
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Affiliation(s)
- Huaye Xiong
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Haotian Ma
- Health Science Center, Xi' an Jiaotong University, Xi'an 710061, China
| | - Huanyu Zhao
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Linsheng Yang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Bin Hu
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Jie Wang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Xiaojun Shi
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Yueqiang Zhang
- Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Heinz Rennenberg
- Center of Molecular Ecophysiology (CMEP), College of Resources and Environment, Southwest University, Chongqing 400716, China
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-Universität Freiburg Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
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Genetic Architecture and Genome-Wide Adaptive Signatures Underlying Stem Lenticel Traits in Populus tomentosa. Int J Mol Sci 2021; 22:ijms22179249. [PMID: 34502156 PMCID: PMC8431110 DOI: 10.3390/ijms22179249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/21/2021] [Accepted: 08/25/2021] [Indexed: 11/17/2022] Open
Abstract
The stem lenticel is a highly specialized tissue of woody plants that has evolved to balance stem water retention and gas exchange as an adaptation to local environments. In this study, we applied genome-wide association studies and selective sweeping analysis to characterize the genetic architecture and genome-wide adaptive signatures underlying stem lenticel traits among 303 unrelated accessions of P. tomentosa, which has significant phenotypic and genetic variations according to climate region across its natural distribution. In total, we detected 108 significant single-nucleotide polymorphisms, annotated to 88 candidate genes for lenticel, of which 9 causative genes showed significantly different selection signatures among climate regions. Furthermore, PtoNAC083 and PtoMYB46 showed significant association signals and abiotic stress response, so we overexpressed these two genes in Arabidopsis thaliana and found that the number of stem cells in all three overexpression lines was significantly reduced by PtoNAC083 overexpression but slightly increased by PtoMYB46 overexpression, suggesting that both genes are involved in cell division and expansion during lenticel formation. The findings of this study demonstrate the successful application of an integrated strategy for dissecting the genetic basis and landscape genetics of complex adaptive traits, which will facilitate the molecular design of tree ideotypes that may adapt to future climate and environmental changes.
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Li G, Lin R, Egekwu C, Blakeslee J, Lin J, Pettengill E, Murphy AS, Peer WA, Islam N, Babst BA, Gao F, Komarov S, Tai YC, Coleman GD. Seasonal nitrogen remobilization and the role of auxin transport in poplar trees. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:4512-4530. [PMID: 32161967 PMCID: PMC7382381 DOI: 10.1093/jxb/eraa130] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 03/06/2020] [Indexed: 05/31/2023]
Abstract
Seasonal nitrogen (N) cycling in Populus, involves bark storage proteins (BSPs) that accumulate in bark phloem parenchyma in the autumn and decline when shoot growth resumes in the spring. Little is known about the contribution of BSPs to growth or the signals regulating N remobilization from BSPs. Knockdown of BSP accumulation via RNAi and N sink manipulations were used to understand how BSP storage influences shoot growth. Reduced accumulation of BSPs delayed bud break and reduced shoot growth following dormancy. Further, 13N tracer studies also showed that BSP accumulation is an important factor in N partitioning from senescing leaves to bark. Thus, BSP accumulation has a role in N remobilization during N partitioning both from senescing leaves to bark and from bark to expanding shoots once growth commences following dormancy. The bark transcriptome during BSP catabolism and N remobilization was enriched in genes associated with auxin transport and signaling, and manipulation of the source of auxin or auxin transport revealed a role for auxin in regulating BSP catabolism and N remobilization. Therefore, N remobilization appears to be regulated by auxin produced in expanding buds and shoots that is transported to bark where it regulates protease gene expression and BSP catabolism.
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Affiliation(s)
- Gen Li
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Rongshoung Lin
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Chioma Egekwu
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Joshua Blakeslee
- OARDC Metabolite Analysis Center, Department of Horticulture and Crop Science, The Ohio State University, Wooster, USA
| | - Jinshan Lin
- OARDC Metabolite Analysis Center, Department of Horticulture and Crop Science, The Ohio State University, Wooster, USA
| | - Emily Pettengill
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Angus S Murphy
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Wendy A Peer
- Department of Environmental Science and Technology, University of Maryland, College Park, USA
| | - Nazrul Islam
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
| | - Benjamin A Babst
- College of Forestry, Agriculture and Natural Resources, University of Arkansas at Monticello, Monticello, USA
| | - Fei Gao
- College of Forestry, Agriculture and Natural Resources, University of Arkansas at Monticello, Monticello, USA
| | - Sergey Komarov
- Department of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Yuan-Chuan Tai
- Department of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Gary D Coleman
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, USA
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Rubio Ames Z, Brecht JK, Olmstead MA. Nitrogen fertilization rates in a subtropical peach orchard: effects on tree vigor and fruit quality. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2020; 100:527-539. [PMID: 31512240 DOI: 10.1002/jsfa.10031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 08/24/2019] [Accepted: 09/03/2019] [Indexed: 05/13/2023]
Abstract
BACKGROUND Nitrogen is a key component of crop production and is commonly related to increases in yield and fruit size. The N fertilization rates used for low-chill peach cultivars were adapted from other peach production regions, where environmental and soil conditions are different. The growth and production as well as the effect on fruit physical and compositional attributes of two low-chill peach cultivars - 'TropicBeauty' (TB) and 'UFSharp' (UFS) - with five different N fertilization rates (0 (N0), 45 (N1), 90 (N2), 179 (N3) and 269 (N4) kg ha-1 applied each year from 2011 to 2017) were examined. RESULTS Peach trees under higher N rates had higher pruning weights compared to the lower N0 or N1 rates. Yield was only affected in 2017 for the two cultivars tested. Physical attributes were inconsistently affected by N. Fruit from the higher N rates had lower a* value (more green) than fruit from the trees under low or zero N. While fruit firmness was not affected by N, fruit from trees under zero/low N had higher total soluble solids in some years. CONCLUSION Considering that N is recycled in the trees, being retained and reused each season to resume growth, it is important to address peach orchard fertilization based on peach tree N status. The results of this experiment show that an increase in N beyond what is required for tree maintenance does not increase yield. In addition, reducing N does not strongly affect fruit quality, although the color and soluble solids results suggest that lower N rates may advance fruit maturation. © 2019 Society of Chemical Industry.
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Affiliation(s)
- Zilfina Rubio Ames
- Horticultural Science Department, IFAS, University of Florida, Gainesville, FL, USA
| | - Jeffrey K Brecht
- Horticultural Science Department, IFAS, University of Florida, Gainesville, FL, USA
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Comparative Proteomic Analysis Unveils Critical Pathways Underlying the Role of Nitrogen Fertilizer Treatment in American Elderberry. Proteomes 2019; 7:proteomes7010010. [PMID: 30897755 PMCID: PMC6473435 DOI: 10.3390/proteomes7010010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 03/04/2019] [Accepted: 03/18/2019] [Indexed: 12/24/2022] Open
Abstract
American elderberry (Sambucus nigra subsp. canadensis) is a rapidly growing specialty crop in Missouri and eastern North America. Nitrogen (N) is a major nutrient involved in plant growth and development. However, proteome changes for different genotypes of elder in response to varying levels of N-treatment remain undefined. To reveal plant responses to N, comparative proteomic analyses were performed to determine consistent changes in three genotypes of elderberry leaves (Adams II, Bob Gordon and Wyldewood) grown under different N-fertilizer treatments. 165 proteins separated by two dimensional gel electrophoresis showed significant differences in abundance (p < 0.05 and greater than 2-fold). Principal component analysis of the abundance profiles of these proteins revealed Bob Gordon as a distinct genotype. The 165 proteins were identified by mass spectrometry and showed similar functional distributions in these genotypes underlying the N-treatment. Among the proteins identified, 23 are mainly involved in photosynthesis, protein metabolism and redox homeostasis. Their abundance profiles were not altered upon exposure to N or genotype. These results provide novel insights into plant responses to fertilizer treatment at the proteome level and could lead to a better understanding of molecular mechanisms of elderberry growth.
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2D-DIGE comparative proteomic analysis of developing wheat grains under high-nitrogen fertilization revealed key differentially accumulated proteins that promote storage protein and starch biosyntheses. Anal Bioanal Chem 2018; 410:6219-6235. [PMID: 30058028 DOI: 10.1007/s00216-018-1230-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/26/2018] [Accepted: 06/26/2018] [Indexed: 12/30/2022]
Abstract
Nitrogen (N) serves as a macronutrient that is essential to plant growth and development, and significantly influences storage protein and starch biosyntheses and, ultimately, grain yield and quality. In this study, we performed the first comparative proteomic analysis of developing wheat grains under high-N conditions using 2D-DIGE and tandem mass spectrometry. High-N fertilizer application caused significant increases in ear number, ear grain number, and grain yield. 2D-DIGE identified 142 differentially accumulated proteins (DAPs) during grain development in the elite Chinese bread wheat cultivar Zhongmai 175, of which 132 (93%) were identified by MALDI-TOF/TOF-MS, representing 92 unique proteins. These proteins are involved mainly in energy, N and protein metabolism, carbon metabolism, and starch biosynthesis. Subcellular localization prediction and fluorescence confocal microscopic analysis showed that the DAPs identified were localized mainly in the cytosol and chloroplast. Principal component analysis (PCA) revealed a greater proteomic difference among grain developmental periods than between the high-N and control groups. Protein-protein interaction analysis highlighted a complex network centered around enzymes involved in energy, N and protein metabolism, and starch biosynthesis. Six key DAP genes showed expression patterns consistent with their protein accumulation trends during grain development. A putative metabolic pathway was proposed, with synergistic regulatory networks of grain storage protein and starch biosyntheses in response to high-N application.
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Di Silvestre D, Bergamaschi A, Bellini E, Mauri P. Large Scale Proteomic Data and Network-Based Systems Biology Approaches to Explore the Plant World. Proteomes 2018; 6:proteomes6020027. [PMID: 29865292 PMCID: PMC6027444 DOI: 10.3390/proteomes6020027] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 05/30/2018] [Accepted: 06/01/2018] [Indexed: 12/26/2022] Open
Abstract
The investigation of plant organisms by means of data-derived systems biology approaches based on network modeling is mainly characterized by genomic data, while the potential of proteomics is largely unexplored. This delay is mainly caused by the paucity of plant genomic/proteomic sequences and annotations which are fundamental to perform mass-spectrometry (MS) data interpretation. However, Next Generation Sequencing (NGS) techniques are contributing to filling this gap and an increasing number of studies are focusing on plant proteome profiling and protein-protein interactions (PPIs) identification. Interesting results were obtained by evaluating the topology of PPI networks in the context of organ-associated biological processes as well as plant-pathogen relationships. These examples foreshadow well the benefits that these approaches may provide to plant research. Thus, in addition to providing an overview of the main-omic technologies recently used on plant organisms, we will focus on studies that rely on concepts of module, hub and shortest path, and how they can contribute to the plant discovery processes. In this scenario, we will also consider gene co-expression networks, and some examples of integration with metabolomic data and genome-wide association studies (GWAS) to select candidate genes will be mentioned.
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Affiliation(s)
- Dario Di Silvestre
- Institute for Biomedical Technologies-National Research Council; F.lli Cervi 93, 20090 Segrate, Milan, Italy.
| | - Andrea Bergamaschi
- Institute for Biomedical Technologies-National Research Council; F.lli Cervi 93, 20090 Segrate, Milan, Italy.
| | - Edoardo Bellini
- Institute for Biomedical Technologies-National Research Council; F.lli Cervi 93, 20090 Segrate, Milan, Italy.
| | - PierLuigi Mauri
- Institute for Biomedical Technologies-National Research Council; F.lli Cervi 93, 20090 Segrate, Milan, Italy.
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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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Zhang X, Misra A, Nargund S, Coleman GD, Sriram G. Concurrent isotope-assisted metabolic flux analysis and transcriptome profiling reveal responses of poplar cells to altered nitrogen and carbon supply. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 93:472-488. [PMID: 29193384 DOI: 10.1111/tpj.13792] [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: 03/14/2017] [Revised: 11/15/2017] [Accepted: 11/23/2017] [Indexed: 05/20/2023]
Abstract
Reduced nitrogen is indispensable to plants. However, its limited availability in soil combined with the energetic and environmental impacts of nitrogen fertilizers motivates research into molecular mechanisms toward improving plant nitrogen use efficiency (NUE). We performed a systems-level investigation of this problem by employing multiple 'omics methodologies on cell suspensions of hybrid poplar (Populus tremula × Populus alba). Acclimation and growth of the cell suspensions in four nutrient regimes ranging from abundant to deficient supplies of carbon and nitrogen revealed that cell growth under low-nitrogen levels was associated with substantially higher NUE. To investigate the underlying metabolic and molecular mechanisms, we concurrently performed steady-state 13 C metabolic flux analysis with multiple isotope labels and transcriptomic profiling with cDNA microarrays. The 13 C flux analysis revealed that the absolute flux through the oxidative pentose phosphate pathway (oxPPP) was substantially lower (~threefold) under low-nitrogen conditions. Additionally, the flux partitioning ratio between the tricarboxylic acid cycle and anaplerotic pathways varied from 84%:16% under abundant carbon and nitrogen to 55%:45% under deficient carbon and nitrogen. Gene expression data, together with the flux results, suggested a plastidic localization of the oxPPP as well as transcriptional regulation of certain metabolic branchpoints, including those between glycolysis and the oxPPP. The transcriptome data also indicated that NUE-improving mechanisms may involve a redirection of excess carbon to aromatic metabolic pathways and extensive downregulation of potentially redundant genes (in these heterotrophic cells) that encode photosynthetic and light-harvesting proteins, suggesting the recruitment of these proteins as nitrogen sinks in nitrogen-abundant conditions.
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Affiliation(s)
- Xiaofeng Zhang
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, 20742, USA
| | - Ashish Misra
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, 20742, USA
| | - Shilpa Nargund
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, 20742, USA
| | - Gary D Coleman
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, 20742, USA
| | - Ganesh Sriram
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD, 20742, USA
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Brunner AM, Varkonyi-Gasic E, Jones RC. Phase Change and Phenology in Trees. COMPARATIVE AND EVOLUTIONARY GENOMICS OF ANGIOSPERM TREES 2017. [DOI: 10.1007/7397_2016_30] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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