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van Bel AJE. The plant axis as the command centre for (re)distribution of sucrose and amino acids. JOURNAL OF PLANT PHYSIOLOGY 2021; 265:153488. [PMID: 34416599 DOI: 10.1016/j.jplph.2021.153488] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/13/2021] [Accepted: 08/01/2021] [Indexed: 06/13/2023]
Abstract
Along with the increase in size required for optimal colonization of terrestrial niches, channels for bidirectional bulk transport of materials in land plants evolved during a period of about 100 million years. These transport systems are essentially still in operation - though perfected over the following 400 million years - and make use of hydrostatic differentials. Substances are accumulated or released at the loading and unloading ends, respectively, of the transport channels. The intermediate stretch between the channel termini is bifunctional and executes orchestrated release and retrieval of solutes. Analyses of anatomical and physiological data demonstrate that the release/retrieval zone extends deeper into sources and sinks than is commonly thought and covers usually much more than 99% of the translocation stretch. This review sketches the significance of events in the intermediate stretch for distribution of organic materials over the plant body. Net leakage from the channels does not only serve maintenance and growth of tissues along the pathway, but also diurnal, short-term or seasonal storage of reserve materials, and balanced distribution of organic C- and N-compounds over axial and terminal sinks. Release and retrieval are controlled by plasma-membrane transporters at the vessel/parenchyma interface in the contact pits along xylem vessels and by plasma-membrane transporters at the interface between companion cells and phloem parenchyma along sieve tubes. The xylem-to-phloem pathway vice versa is a bifacial, radially oriented system comprising a symplasmic pathway, of which entrance and exit are controlled at specific membrane checkpoints, and a parallel apoplasmic pathway. A broad range of specific sucrose and amino-acid transporters are deployed at the checkpoint plasma membranes. SUCs, SUTs, STPs, SWEETs, and AAPs, LTHs, CATs are localized to the plasma membranes in question, both in monocots and eudicots. Presence of Umamits in monocots is uncertain. There is some evidence for endo- and exocytosis at the vessel/parenchyma interface supplementary to the transporter-mediated uptake and release. Actions of transporters at the checkpoints are equally decisive for storage and distribution of amino acids and sucrose in monocots and eudicots, but storage and distribution patterns may differ between both taxa. While the majority of reserves is sequestered in vascular parenchyma cells in dicots, lack of space in monocot vasculature urges "outsourcing" of storage in ground parenchyma around the translocation path. In perennial dicots, specialized radial pathways (rays) include the sites for seasonal alternation of storage and mobilization. In dicots, apoplasmic phloem loading and a correlated low rate of release along the path would favour supply with photoassimilates of terminal sinks, while symplasmic phloem loading and a correlated higher rate of release along the path favours supply of axial sinks and transfer to the xylem. The balance between the resource acquisition by terminal and axial sinks is an important determinant of relative growth rate and, hence, for the fitness of plants in various habitats. Body enlargement as the evolutionary drive for emergence of vascular systems and mass transport propelled by hydrostatic differentials.
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Affiliation(s)
- Aart J E van Bel
- Institute of Phythopathology, Centre for BioSystems, Land Use and Nutrition, Justus-Liebig University, Heinrich-Buff-Ring 26-32, D-35392, Giessen, Germany.
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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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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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Netzer F, Mueller CW, Scheerer U, Grüner J, Kögel-Knabner I, Herschbach C, Rennenberg H. Phosphorus nutrition of Populus × canescens reflects adaptation to high P-availability in the soil. TREE PHYSIOLOGY 2018; 38:6-24. [PMID: 29077948 DOI: 10.1093/treephys/tpx126] [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: 04/20/2017] [Accepted: 09/13/2017] [Indexed: 05/04/2023]
Abstract
Phosphorus (P) constitutes one of five macronutrients essential for plant growth and development due to the central function of phosphate in energy metabolism, inheritance and metabolic control. In many ecosystems, plant available soil-P gets limited by soil aging. Hence, plants have developed adaptation strategies to cope with such limitation by an efficient plant and ecosystem internal P-cycling during annual growth. The natural floodplain habitat of fast-growing Populus × canescens is characterized by high soil-P availability. It was thus expected that the P-nutrition of P. × canescens had adapted to this conditions. Therefore, different P-fractions in different twig tissues were investigated during two annual growth cycles. The P-nutrition of P. × canescens markedly differs from that of European beech grown at low soil-P availability (Netzer F, Schmid C, Herschbach C, Rennenberg H (2017) Phosphorus-nutrition of European beech (Fagus sylvatica L.) during annual growth depends on tree age and P-availability in the soil. Environ Exp Bot 137:194-207). This was mainly due to a lack of tree internal P-cycling during annual growth indicated by the absence of P-storage and remobilization in twig bark and wood. Hence, strategies to economize P-nutrition and to prevent P-losses had not developed. This fits with the fast-growth strategy of P. × canescens at unrestricted P-availability. Hence, the P-nutrition strategy of P. × canescens can be seen as an evolutionary adaptation to its natural growth habitat.
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Affiliation(s)
- Florian Netzer
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
| | - Carsten W Mueller
- Chair of Soil Science, Department of Ecology and Ecosystem Management, Wissenschaftszentrum Weihenstephan, Emil-Ramann-Straße 2, 85354 Freising, Germany
| | - Ursula Scheerer
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
| | - Jörg Grüner
- Chair of Forest Botany, Albert-Ludwigs-University Freiburg, Bertoldstraße 17, 79085 Freiburg, Germany
| | - Ingrid Kögel-Knabner
- Chair of Soil Science, Department of Ecology and Ecosystem Management, Wissenschaftszentrum Weihenstephan, Emil-Ramann-Straße 2, 85354 Freising, Germany
- Institute for Advanced Study, Technical University of Munich, 85748 Garching, Germany
| | - Cornelia Herschbach
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
| | - Heinz Rennenberg
- Chair of Tree Physiology, Institute of Forest Sciences, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 53/54, 79110 Freiburg, Germany
- King Saud University, College of Science, PO Box 2455, Riyadh 11451, Saudi Arabia
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Ben Abdallah M, Trupiano D, Polzella A, De Zio E, Sassi M, Scaloni A, Zarrouk M, Ben Youssef N, Scippa GS. Unraveling physiological, biochemical and molecular mechanisms involved in olive (Olea europaea L. cv. Chétoui) tolerance to drought and salt stresses. JOURNAL OF PLANT PHYSIOLOGY 2018; 220:83-95. [PMID: 29161576 DOI: 10.1016/j.jplph.2017.10.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/20/2017] [Accepted: 10/23/2017] [Indexed: 05/26/2023]
Abstract
Olive (Olea europaea L.) is an economically important crop for the Mediterranean basin, where prolonged drought and soil salinization may occur. This plant has developed a series of mechanisms to tolerate and grow under these adverse conditions. By using an integrated approach, we described in Chétoui olive cultivar the changes in plant growth, oxidative damage and osmolyte accumulation in leaves, in combination with corresponding changes in physiological parameters and proteome. Our results showed, under both stress conditions, a greater growth reduction of the aboveground plant organs than of the underground counterparts. This was associated with a reduction of all photosynthetic parameters, the integrity of photosystem II and leaf nitrogen content, and corresponding representation of photosynthetic apparatus proteins, Calvin-Benson cycle and nitrogen metabolism. The most significant changes were observed under the salinity stress condition. Oxidative stress was also observed, in particular, lipid peroxidation, which could be tentatively balanced by a concomitant photoprotective/antioxidative increase of carotenoid levels. At the same time, various compensative mechanisms to cope with nitrogen source demands and to control plant cell osmolarity were also shown by olive plants under these stresses. Taken together, these findings suggest that the Chétoui variety is moderately sensitive to both drought and salt stress, although it has greater ability to tolerate water depletion.
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Affiliation(s)
- Mariem Ben Abdallah
- Laboratory of Olive Biotechnology, University Tunis El Manar, Biotechnology Center of Borj-Cedria, 2050 Hammam-Lif, Tunisia
| | - Dalila Trupiano
- Department of Bioscience and Territory, University of Molise, 86090 Pesche, Italy.
| | - Antonella Polzella
- Department of Bioscience and Territory, University of Molise, 86090 Pesche, Italy
| | - Elena De Zio
- Department of Bioscience and Territory, University of Molise, 86090 Pesche, Italy
| | - Mauro Sassi
- Proteomics and Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Napoli, Italy
| | - Andrea Scaloni
- Proteomics and Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Napoli, Italy
| | - Mokhtar Zarrouk
- Laboratory of Olive Biotechnology, University Tunis El Manar, Biotechnology Center of Borj-Cedria, 2050 Hammam-Lif, Tunisia
| | - Nabil Ben Youssef
- Laboratory of Olive Biotechnology, University Tunis El Manar, Biotechnology Center of Borj-Cedria, 2050 Hammam-Lif, Tunisia; Department of Biology, College of Sciences, University of Dammam, 31451 Dammam, Saudi Arabia
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Kavka M, Polle A. Dissecting nutrient-related co-expression networks in phosphate starved poplars. PLoS One 2017; 12:e0171958. [PMID: 28222153 PMCID: PMC5319788 DOI: 10.1371/journal.pone.0171958] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/29/2017] [Indexed: 11/18/2022] Open
Abstract
Phosphorus (P) is an essential plant nutrient, but its availability is often limited in soil. Here, we studied changes in the transcriptome and in nutrient element concentrations in leaves and roots of poplars (Populus × canescens) in response to P deficiency. P starvation resulted in decreased concentrations of S and major cations (K, Mg, Ca), in increased concentrations of N, Zn and Al, while C, Fe and Mn were only little affected. In roots and leaves >4,000 and >9,000 genes were differently expressed upon P starvation. These genes clustered in eleven co-expression modules of which seven were correlated with distinct elements in the plant tissues. One module (4.7% of all differentially expressed genes) was strongly correlated with changes in the P concentration in the plant. In this module the GO term "response to P starvation" was enriched with phosphoenolpyruvate carboxylase kinases, phosphatases and pyrophosphatases as well as regulatory domains such as SPX, but no phosphate transporters. The P-related module was also enriched in genes of the functional category "galactolipid synthesis". Galactolipids substitute phospholipids in membranes under P limitation. Two modules, one correlated with C and N and the other with biomass, S and Mg, were connected with the P-related module by co-expression. In these modules GO terms indicating "DNA modification" and "cell division" as well as "defense" and "RNA modification" and "signaling" were enriched; they contained phosphate transporters. Bark storage proteins were among the most strongly upregulated genes in the growth-related module suggesting that N, which could not be used for growth, accumulated in typical storage compounds. In conclusion, weighted gene coexpression network analysis revealed a hierarchical structure of gene clusters, which separated phosphate starvation responses correlated with P tissue concentrations from other gene modules, which most likely represented transcriptional adjustments related to down-stream nutritional changes and stress.
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Affiliation(s)
- Mareike Kavka
- Forstbotanik und Baumphysiologie, Georg-August Universität Göttingen, Göttingen, Germany
- Labor für Radio-Isotope, Georg-August Universität Göttingen, Göttingen, Germany
| | - Andrea Polle
- Forstbotanik und Baumphysiologie, Georg-August Universität Göttingen, Göttingen, Germany
- Labor für Radio-Isotope, Georg-August Universität Göttingen, Göttingen, Germany
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7
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Peng YL, Wang YS, Cheng H, Wang LY. Characterization and expression analysis of a gene encoding CBF/DREB1 transcription factor from mangrove Aegiceras corniculatum. ECOTOXICOLOGY (LONDON, ENGLAND) 2015; 24:1733-1743. [PMID: 25976917 DOI: 10.1007/s10646-015-1485-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/08/2015] [Indexed: 06/04/2023]
Abstract
Several transcription factors play important roles in survival of plants under cold, drought and salt stresses by serving as master regulator of sets of downstream stress-responsive genes. A gene encoding CBF/DREB1 transcription factor (C-repeat binding factor/dehydration responsive element-binding factor 1) was isolated from mangrove Aegiceras corniculatum and designated AcCBF1. The full-length cDNA of AcCBF1 was 896 bp containing 618 bp ORF encoding a protein of 205 amino acids. Multiple sequence analysis showed that the corresponding protein had 100 % identity to AmCBF1 (KC776908) from mangrove Avicennia marina, and contains an AP2/ERE DNA-binding domain and two CBF signature sequences. Expression analyses based on quantitative real-time PCR revealed that the AcCBF1 gene was expressed in all tissues of A. corniculatum under normal condition with the highest expression level detected in leaves. When exposed to abiotic stresses, AcCBF1 gene showed different expression patterns in different tissues. Generally, AcCBF1 gene could be rapidly and strongly induced by cold and drought, while slightly induced by abscisic acid and salinity. Furthermore, light could positively regulate the cold-induction level of AcCBF1. These results suggest that the AcCBF1 may be playing important role in the signaling pathway of cold stress and also involved in the cross-talk among abiotic stresses. Further studies focusing on the promotors and downstream stress-responsive genes of AcCBF1 will help to better understand the regulatory mechanisms of mangrove A. corniculatum under abiotic stresses.
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Affiliation(s)
- Ya-Lan Peng
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - You-Shao Wang
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.
- Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, 518121, China.
| | - Hao Cheng
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Li-Ying Wang
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
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Islam N, Li G, Garrett WM, Lin R, Sriram G, Cooper B, Coleman GD. Proteomics of Nitrogen Remobilization in Poplar Bark. J Proteome Res 2014; 14:1112-26. [DOI: 10.1021/pr501090p] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Nazrul Islam
- Department
of Plant Sciences and Landscape Architecture, University of Maryland, College
Park, Maryland 20742, United States
| | - Gen Li
- Department
of Plant Sciences and Landscape Architecture, University of Maryland, College
Park, Maryland 20742, United States
| | - Wesley M. Garrett
- Animal
Biosciences and Biotechnology Laboratory, USDA-ARS, Beltsville, Maryland 20705, United States
| | - Rongshuang Lin
- Department
of Plant Sciences and Landscape Architecture, University of Maryland, College
Park, Maryland 20742, United States
| | - Ganesh Sriram
- Department
of Chemical and Biomolecular Engineering, University of Maryland, College
Park, Maryland 20742, United States
| | - Bret Cooper
- Soybean
Genomics and Improvement Laboratory, USDA-ARS, Beltsville, Maryland 20705, United States
| | - Gary D. Coleman
- Department
of Plant Sciences and Landscape Architecture, University of Maryland, College
Park, Maryland 20742, United States
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9
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Yordanov YS, Ma C, Strauss SH, Busov VB. EARLY BUD-BREAK 1 (EBB1) is a regulator of release from seasonal dormancy in poplar trees. Proc Natl Acad Sci U S A 2014; 111:10001-6. [PMID: 24951507 PMCID: PMC4103365 DOI: 10.1073/pnas.1405621111] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Trees from temperate latitudes transition between growth and dormancy to survive dehydration and freezing stress during winter months. We used activation tagging to isolate a dominant mutation affecting release from dormancy and identified the corresponding gene EARLY BUD-BREAK 1 (EBB1). We demonstrate through positioning of the tag, expression analysis, and retransformation experiments that EBB1 encodes a putative APETALA2/Ethylene responsive factor transcription factor. Transgenic up-regulation of the gene caused early bud-flush, whereas down-regulation delayed bud-break. Native EBB1 expression was highest in actively growing apices, undetectable during the dormancy period, but rapidly increased before bud-break. The EBB1 transcript was localized in the L1/L2 layers of the shoot meristem and leaf primordia. EBB1-overexpressing transgenic plants displayed enlarged shoot meristems, open and poorly differentiated buds, and a higher rate of cell division in the apex. Transcriptome analyses of the EBB1 transgenics identified 971 differentially expressed genes whose expression correlated with the EBB1 expression changes in the transgenic plants. Promoter analysis among the differentially expressed genes for the presence of a canonical EBB1-binding site identified 65 putative target genes, indicative of a broad regulatory context of EBB1 function. Our results suggest that EBB1 has a major and integrative role in reactivation of meristem activity after winter dormancy.
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Affiliation(s)
- Yordan S Yordanov
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931; and
| | - Cathleen Ma
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331-5752
| | - Steven H Strauss
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331-5752
| | - Victor B Busov
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931; and
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Kurita Y, Baba K, Ohnishi M, Anegawa A, Shichijo C, Kosuge K, Fukaki H, Mimura T. Establishment of a shortened annual cycle system; a tool for the analysis of annual re-translocation of phosphorus in the deciduous woody plant (Populus alba L.). JOURNAL OF PLANT RESEARCH 2014; 127:545-551. [PMID: 24848773 DOI: 10.1007/s10265-014-0634-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 03/06/2014] [Indexed: 06/03/2023]
Abstract
The supply of phosphorus, the essential element for plant growth and development, is often limited in natural environments. Plants employ multiple physiological strategies to minimize the impact of phosphate deficiency. In deciduous trees, phosphorus is remobilized from senescing leaves in autumn and stored in other tissues for reuse in the following spring. We previously monitored the annual changes in leaf phosphate content of white poplar (Populus alba) growing under natural conditions and found that about 75 % of inorganic and 60 % of organic leaf phosphates observed in May were remobilized by November. In order to analyze this process (such annual events), we have established a model system, in which an annual cycle of phosphate re-translocation in trees can be simulated under laboratory conditions by controlling temperature and photoperiod (='shortened annual cycle'). This system evidently allowed us to monitor the annual changes in leaf color, phosphate remobilization from senescent leaves, and bud break in the next spring within five months. This will greatly facilitate the analysis of cellular and molecular mechanisms of annual phosphate re-translocation in deciduous trees.
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Affiliation(s)
- Yuko Kurita
- Department of Biology, Graduate School of Science, Kobe University, Rokkodai, Nada, Kobe, 657-8501, Japan
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11
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Nargund S, Misra A, Zhang X, Coleman GD, Sriram G. Flux and reflux: metabolite reflux in plant suspension cells and its implications for isotope-assisted metabolic flux analysis. MOLECULAR BIOSYSTEMS 2014; 10:1496-508. [PMID: 24675729 DOI: 10.1039/c3mb70348g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Isotope-assisted metabolic flux analysis (MFA) is a powerful methodology to quantify intracellular fluxes via isotope labeling experiments (ILEs). In batch cultures, which are often convenient, inexpensive or inevitable especially for eukaryotic systems, MFA is complicated by the presence of the initially present biomass. This unlabeled biomass may either mix with the newly synthesized labeled biomass or reflux into the metabolic network, thus masking the true labeling patterns in the newly synthesized biomass. Here, we report a detailed investigation of such metabolite reflux in cell suspensions of the tree poplar. In ILEs supplying 28% or 98% U-(13)C glucose as the sole organic carbon source, biomass components exhibited lower (13)C enrichments than the supplied glucose as well as anomalous isotopomers not explainable by simple mixing of the initial and newly synthesized biomass. These anomalous labeling patterns were most prominent in a 98% U-(13)C glucose ILE. By comparing the performance of light- and dark-grown cells as well as by analyzing the isotope labeling patterns in aspartic and glutamic acids, we eliminated photosynthetic or anaplerotic fixation of extracellular (12)CO2 as explanations for the anomalous labeling patterns. We further investigated four different metabolic models for interpreting the labeling patterns and evaluating fluxes: (i) a carbon source (glucose) dilution model, (ii) an isotopomer correction model with uniform dilution for all amino acids, (iii) an isotopomer correction model with variable dilution for different amino acids, and (iv) a comprehensive metabolite reflux model. Of these, the metabolite reflux model provided a substantially better fit for the observed labeling patterns (sum of squared residues: 538) than the other three models whose sum of squared residues were (i) 4626, (ii) 4983, and (iii) 1748, respectively. We compared fluxes determined using the metabolite reflux model to those determined using an independent methodology involving an excessively long ILE to wash out initial biomass and a minimal reflux model. This comparison showed identical or similar distributions for a majority of fluxes, thus validating our comprehensive reflux model. In summary, we have demonstrated the need for quantifying interactions between initially present biomass and newly synthesized biomass in batch ILEs, especially through the use of ≈100% U-(13)C carbon sources. Our ILEs reveal a high amount of metabolite reflux in poplar cell suspensions, which is well explained by a comprehensive metabolite reflux model.
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Affiliation(s)
- Shilpa Nargund
- Department of Chemical and Biomolecular Engineering, University of Maryland, 1208D, Chemical and Nuclear Engineering Building 090, College Park, MD 20742, USA.
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12
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Pettengill EA, Pettengill JB, Coleman GD. Elucidating the evolutionary history and expression patterns of nucleoside phosphorylase paralogs (vegetative storage proteins) in Populus and the plant kingdom. BMC PLANT BIOLOGY 2013; 13:118. [PMID: 23957885 PMCID: PMC3751785 DOI: 10.1186/1471-2229-13-118] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 08/15/2013] [Indexed: 05/09/2023]
Abstract
BACKGROUND Nucleoside phosphorylases (NPs) have been extensively investigated in human and bacterial systems for their role in metabolic nucleotide salvaging and links to oncogenesis. In plants, NP-like proteins have not been comprehensively studied, likely because there is no evidence of a metabolic function in nucleoside salvage. However, in the forest trees genus Populus a family of NP-like proteins function as an important ecophysiological adaptation for inter- and intra-seasonal nitrogen storage and cycling. RESULTS We conducted phylogenetic analyses to determine the distribution and evolution of NP-like proteins in plants. These analyses revealed two major clusters of NP-like proteins in plants. Group I proteins were encoded by genes across a wide range of plant taxa while proteins encoded by Group II genes were dominated by species belonging to the order Malpighiales and included the Populus Bark Storage Protein (BSP) and WIN4-like proteins. Additionally, we evaluated the NP-like genes in Populus by examining the transcript abundance of the 13 NP-like genes found in the Populus genome in various tissues of plants exposed to long-day (LD) and short-day (SD) photoperiods. We found that all 13 of the Populus NP-like genes belonging to either Group I or II are expressed in various tissues in both LD and SD conditions. Tests of natural selection and expression evolution analysis of the Populus genes suggests that divergence in gene expression may have occurred recently during the evolution of Populus, which supports the adaptive maintenance models. Lastly, in silico analysis of cis-regulatory elements in the promoters of the 13 NP-like genes in Populus revealed common regulatory elements known to be involved in light regulation, stress/pathogenesis and phytohormone responses. CONCLUSION In Populus, the evolution of the NP-like protein and gene family has been shaped by duplication events and natural selection. Expression data suggest that previously uncharacterized NP-like proteins may function in nutrient sensing and/or signaling. These proteins are members of Group I NP-like proteins, which are widely distributed in many plant taxa. We conclude that NP-like proteins may function in plants, although this function is undefined.
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Affiliation(s)
- Emily A Pettengill
- Department of Plant Science and Landscape Architecture, University of Maryland, Plant Science Building, College Park, Maryland, 20742, USA
| | - James B Pettengill
- Department of Plant Science and Landscape Architecture, University of Maryland, Takoma Park, Maryland, USA
| | - Gary D Coleman
- Department of Plant Science and Landscape Architecture, University of Maryland, Plant Science Building, College Park, Maryland, 20742, USA
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Wildhagen H, Bilela S, Rennenberg H. Low temperatures counteract short-day induced nitrogen storage, but not accumulation of bark storage protein transcripts in bark of grey poplar (Populus × canescens) trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2013; 15 Suppl 1:44-56. [PMID: 23279294 DOI: 10.1111/j.1438-8677.2012.00687.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 09/21/2012] [Indexed: 05/13/2023]
Abstract
According to climate change scenarios, the seasonal course of temperature will change in most regions of the world, raising the question of how this will influence seasonal nitrogen (N) storage in deciduous trees. The key to this question is a detailed understanding of the underlying regulatory mechanisms, which was addressed in this study by analysing (i) the effects of low temperatures (13-1 °C) on bark storage protein (BSP) transcription, BSP and total protein accumulation and amino acid metabolism; (ii) the effects of interactions between low temperatures and photoperiod on these processes; and (iii) the regulatory role of amino acids in the bark. For this purpose, we exposed grey poplar trees (Populus × canescens) to three different treatments of changing photoperiod at constant temperature, changing temperature at constant photoperiod, and both changing photoperiod and temperature. Under a shortened photoperiod, a substantial increase of BSP transcripts was observed that was correlated with the accumulation of bark proteins, indicating a metabolic shift to promote long-term N storage. Irrespective of the applied photoperiod, exposure to low temperatures (5 or 1 °C) caused a strong increase of BSP transcripts, which was not paralled by significant increases of BSP and total bark proteins. We conclude that the interaction between effects of photoperiod and temperature is dependent on the carbon status of the trees, and reflects a metabolic adjustment of reduced carbon consumption for BSP synthesis. These results demonstrate the differential temperature sensitivity of processes involved in seasonal N storage, implying vulnerability to changing environmental conditions.
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Affiliation(s)
- H Wildhagen
- Albert-Ludwigs-University Freiburg, Chair of Tree Physiology, Institute of Forest Botany and Tree Physiology, Freiburg, Germany
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Pettengill EA, Parmentier-Line C, Coleman GD. Evaluation of qPCR reference genes in two genotypes of Populus for use in photoperiod and low-temperature studies. BMC Res Notes 2012; 5:366. [PMID: 22824181 PMCID: PMC3479007 DOI: 10.1186/1756-0500-5-366] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 06/29/2012] [Indexed: 11/25/2022] Open
Abstract
Background Quantitative PCR (qPCR) is a widely used technique for gene expression analysis. A common normalization method for accurate qPCR data analysis involves stable reference genes to determine relative gene expression. Despite extensive research in the forest tree species Populus, there is not a resource for reference genes that meet the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) standards for qPCR techniques and analysis. Since Populus is a woody perennial species, studies of seasonal changes in gene expression are important towards advancing knowledge of this important developmental and physiological trait. The objective of this study was to evaluate reference gene expression stability in various tissues and growth conditions in two important Populus genotypes (P. trichocarpa “Nisqually 1” and P. tremula x P. alba 717 1-B4) following MIQE guidelines. Results We evaluated gene expression stability in shoot tips, young leaves, mature leaves and bark tissues from P. trichocarpa and P. tremula. x P. alba grown under long-day (LD), short-day (SD) or SD plus low-temperatures conditions. Gene expression data were analyzed for stable reference genes among 18S rRNA, ACT2, CDC2, CYC063, TIP4-like, UBQ7, PT1 and ANT using two software packages, geNormPLUS and BestKeeper. GeNormPLUS ranked TIP4-like and PT1 among the most stable genes in most genotype/tissue combinations while BestKeeper ranked CDC2 and ACT2 among the most stable genes. Conclusions This is the first comprehensive evaluation of reference genes in two important Populus genotypes and the only study in Populus that meets MIQE standards. Both analysis programs identified stable reference genes in both genotypes and all tissues grown under different photoperiods. This set of reference genes was found to be suitable for either genotype considered here and may potentially be suitable for other Populus species and genotypes. These results provide a valuable resource for the Populus research community.
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Affiliation(s)
- Emily A Pettengill
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742-4452, USA
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Millard P, Grelet GA. Nitrogen storage and remobilization by trees: ecophysiological relevance in a changing world. TREE PHYSIOLOGY 2010; 30:1083-95. [PMID: 20551251 DOI: 10.1093/treephys/tpq042] [Citation(s) in RCA: 169] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The role of carbon (C) and nitrogen (N) storage by trees will be discussed in terms of uncoupling their growth from resource acquisition. There are profound differences between the physiology of C and N storage. C storage acts as a short-term, temporary buffer when photosynthesis cannot meet current sink demand and remobilization is sink driven. However, the majority of C allocated to non-structural carbohydrates such as starch is not reused so is in fact sequestered, not stored. In contrast, N storage is seasonally programmed, closely linked to tree phenology and operates at temporal scales of months to years, with remobilization being source driven. We examine the ecological significance of N storage and remobilization in terms of regulating plant N use efficiency, allowing trees to uncouple seasonal growth from N uptake by roots and allowing recovery from disturbances such as browsing damage. We also briefly consider the importance of N storage and remobilization in regulating how trees will likely respond to rising atmospheric carbon dioxide concentrations. Most studies of N storage and remobilization have been restricted to small trees growing in a controlled environment where (15)N can be used easily as a tracer for mineral N. We highlight the need to describe and quantify these processes for adult trees in situ where most root N uptake occurs via ectomycorrhizal partners, an approach that now appears feasible for deciduous trees through quantification of the flux of remobilized N in their xylem. This opens new possibilities for studying interactions between N and C allocation in trees and associated mycorrhizal partners, which are likely to be crucial in regulating the response of trees to many aspects of global environmental change.
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Affiliation(s)
- Peter Millard
- Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen, UK.
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Wildhagen H, Dürr J, Ehlting B, Rennenberg H. Seasonal nitrogen cycling in the bark of field-grown Grey poplar is correlated with meteorological factors and gene expression of bark storage proteins. TREE PHYSIOLOGY 2010; 30:1096-110. [PMID: 20354193 DOI: 10.1093/treephys/tpq018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Seasonal tree-internal nitrogen cycling is an important strategy for trees to achieve high efficiency in the use of nitrogen (N). Key processes of this N redistribution are autumnal leaf senescence and storage of released N as bark storage proteins (BSP) in perennial tissues. While the regulation of leaf senescence has been intensively analysed in trees, the coordination of the complementary storage processes is still poorly understood. Therefore, we ascertained relationships between physiological-level and molecular-level processes and environmental factors under natural conditions in the bark of Populus x canescens. We analysed amino-N concentrations, total soluble protein concentration and transcript abundances of BSP genes in the bark of field-grown P. x canescens harvested during two annual growth cycles. By correlation analysis and linear modelling, we assessed interactions between biological data and meteorological conditions. Day length correlated with BSP expression, and air temperature correlated strongly with total protein concentration (r = -0.92), gamma-aminobutyric acid (GABA; r = 0.76) and arginine (r = -0.70). GABA and arginine also correlated significantly with total protein concentration and transcript abundances of BSP genes. We conclude that GABA and arginine potentially contribute to adjust storage processes in the bark of poplar trees to seasonal changes in environmental conditions.
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Affiliation(s)
- Henning Wildhagen
- Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University Freiburg, Georges-Koehler-Allee 053/054, 79110 Freiburg, Germany
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Victor KJ, Fennell AY, Grimplet J. Proteomic analysis of shoot tissue during photoperiod induced growth cessation in V. riparia Michx. grapevines. Proteome Sci 2010; 8:44. [PMID: 20704748 PMCID: PMC2929227 DOI: 10.1186/1477-5956-8-44] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 08/12/2010] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Growth cessation, cold acclimation and dormancy induction in grapevines and other woody perennial plants native to temperate continental climates is frequently triggered by short photoperiods. The early induction of these processes by photoperiod promotes winter survival of grapevines in cold temperate zones. Examining the molecular processes, in particular the proteomic changes in the shoot, will provide greater insight into the signaling cascade that initiates growth cessation and dormancy induction. To begin understanding transduction of the photoperiod signal, Vitis riparia Michx. grapevines that had grown for 35 days in long photoperiod (long day, LD, 15 h) were subjected to either a continued LD or a short photoperiod (short day, SD, 13 h) treatment. Shoot tips (4-node shoot terminals) were collected from each treatment at 7 and 28 days of LD and SD for proteomic analysis via two-dimensional (2D) gel electrophoresis. RESULTS Protein profiles were characterized in V. riparia shoot tips during active growth or SD induced growth cessation to examine physiological alterations in response to differential photoperiod treatments. A total of 1054 protein spots were present on the 2D gels. Among the 1054 proteins, 216 showed differential abundance between LD and SD (>/= two-fold ratio, p-value = 0.05). After 7 days, 39 protein spots were more abundant in LD and 30 were more abundant in SD. After 28 days, 93 protein spots were more abundant in LD and 54 were more abundant in SD. MS/MS spectrometry was performed to determine the functions of the differentially abundant proteins. CONCLUSIONS The proteomics analysis uncovered a portion of the signal transduction involved in V. riparia grapevine growth cessation and dormancy induction. Different enzymes of the Calvin-Benson cycle and glutamate synthetase isoforms were more abundant either in LD or SD treatments. In LD tissues the significantly differentially more abundant proteins included flavonoid biosynthesis and polyphenol enzymes, cinnamyl alcohol dehydrogenase, and TCP-1 complexes. In the SD tissue photorespiratory proteins were more abundant than in the LD. The significantly differentially more abundant proteins in SD were involved in ascorbate biosynthesis, photosystem II and photosystem I subunits, light harvesting complexes, and carboxylation enzymes.
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Affiliation(s)
- Kim J Victor
- Department of Horticulture, Forestry, Landscape, & Parks, Box 2140A, South Dakota State University, Brookings, SD 57007, USA
| | - Anne Y Fennell
- Department of Horticulture, Forestry, Landscape, & Parks, Box 2140A, South Dakota State University, Brookings, SD 57007, USA
| | - Jérôme Grimplet
- Department of Horticulture, Forestry, Landscape, & Parks, Box 2140A, South Dakota State University, Brookings, SD 57007, USA
- Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de La Rioja, Gobierno de La Rioja) Longroño, 26006, Spain
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18
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Rennenberg H, Wildhagen H, Ehlting B. Nitrogen nutrition of poplar trees. PLANT BIOLOGY (STUTTGART, GERMANY) 2010; 12:275-91. [PMID: 20398235 DOI: 10.1111/j.1438-8677.2009.00309.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Many forest ecosystems have evolved at sites with growth-limiting nitrogen (N) availability, low N input from external sources and high ecosystem internal cycling of N. By contrast, many poplar species are frequent constituents of floodplain forests where they are exposed to a significant ecosystem external supply of N, mainly nitrate, in the moving water table. Therefore, nitrate is much more important for N nutrition of these poplar species than for many other tree species. We summarise current knowledge of nitrate uptake and its regulation by tree internal signals, as well as acquisition of ammonium and organic N from the soil. Unlike herbaceous plants, N nutrition of trees is sustained by seasonal, tree internal cycling. Recent advances in the understanding of seasonal storage and mobilisation in poplar bark and regulation of these processes by temperature and daylength are addressed. To explore consequences of global climate change on N nutrition of poplar trees, responses of N uptake and metabolism to increased atmospheric CO(2) and O(3) concentrations, increased air and soil temperatures, drought and salt stress are highlighted.
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Affiliation(s)
- H Rennenberg
- Albert-Ludwigs-University Freiburg, Institute of Forest Botany and Tree Physiology, Freiburg, Germany.
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19
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Fracheboud Y, Luquez V, Björkén L, Sjödin A, Tuominen H, Jansson S. The control of autumn senescence in European aspen. PLANT PHYSIOLOGY 2009; 149:1982-91. [PMID: 19201914 PMCID: PMC2663763 DOI: 10.1104/pp.108.133249] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Accepted: 02/02/2009] [Indexed: 05/18/2023]
Abstract
The initiation, progression, and natural variation of autumn senescence in European aspen (Populus tremula) was investigated by monitoring chlorophyll degradation in (1) trees growing in natural stands and (2) cloned trees growing in a greenhouse under various light regimes. The main trigger for the initiation of autumn senescence in aspen is the shortening photoperiod, but there was a large degree of variation in the onset of senescence, both within local populations and among trees originating from different populations, where it correlated with the latitude of their respective origins. The variation for onset of senescence with a population was much larger than the variation of bud set. Once started, autumn senescence was accelerated by low temperature and longer nights, and clones that started to senescence late had a faster senescence. Bud set and autumn senescence appeared to be under the control of two independent critical photoperiods, but senescence could not be initiated until a certain time after bud set, suggesting that bud set and growth arrest are important for the trees to acquire competence to respond to the photoperiodic trigger to undergo autumn senescence. A timetable of events related to bud set and autumn senescence is presented.
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Affiliation(s)
- Yvan Fracheboud
- Umeå Plant Science Center, Department of Plant Physiology, Umeå University, SE-90187 Umeå, Sweden
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20
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Quecini V. Identification of photoperception and light signal transduction pathways in citrus. Genet Mol Biol 2007. [DOI: 10.1590/s1415-47572007000500007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Cooke JEK, Weih M. Nitrogen storage and seasonal nitrogen cycling in Populus: bridging molecular physiology and ecophysiology. THE NEW PHYTOLOGIST 2005; 167:19-30. [PMID: 15948826 DOI: 10.1111/j.1469-8137.2005.01451.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
While both annual and perennial plants store nitrogen resources during the growing season, seasonal N cycling is a hallmark of the perennial habit. In Populus the vegetative storage proteins BSP, WIN4 and PNI288 all play a role in N storage during active growth, whereas BSP is the major form of reduced N storage during winter dormancy. In this review we explore cellular and molecular events implicated in seasonal N cycling in Populus, as well as environmental cues that modulate both the phenology of seasonal N cycling, and the efficiency and proficiency of autumn N resorption. We highlight recent advances that have been made using Populus genomics resources to address processes germane to seasonal N cycling. Genetic and genetological studies are enabling us to connect our understanding of seasonal N cycling at molecular and cellular levels with that at ecophysiological levels. With the genomics resources and foundational knowledge that are now in place, Populus researchers are poised to build an integrative understanding of seasonal N cycling that spans from genomes to ecosystems.
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Affiliation(s)
- Janice E K Cooke
- Université Laval, Centre de Recherche en Biologie Forestière, Sainte-Foy, Québec G1K 7P4, Canada.
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22
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Jing ZP, Gallardo F, Pascual MB, Sampalo R, Romero J, De Navarra AT, Cánovas FM. Improved growth in a field trial of transgenic hybrid poplar overexpressing glutamine synthetase. THE NEW PHYTOLOGIST 2004; 164:137-145. [PMID: 33873472 DOI: 10.1111/j.1469-8137.2004.01173.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
• In the present work the performance of transgenic poplars expressing a pine glutamine synthetase (GS) transgene was studied in natural conditions. • A field study of eight independent transgenic lines and control plants was carried out for 3 yr in the province of Granada (Spain). • Transgenic poplars reached average heights that were 21, 36 and 41% greater than control plants after the first, second and third year of growth, respectively. Transgene expression affected plant features with time resulting in increased protein, total GS and ferredoxin-dependent glutamate synthase (Fd-GOGAT) in leaves. However, neither differences in the large subunit of Rubisco (LSU) abundance nor water content were detected between lines. Furthermore, no significant differences were found in total polysaccharide and lignin content in tree trunks. • The analyses of stem diameter, and protein contents in the bark suggest that higher levels of nitrogen reserves accumulated in the stem of transgenics. Our results suggest that modification of GS1 expression may be a useful strategy to complement traditional tree breeding in short rotation plantations.
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Affiliation(s)
- Zhong Ping Jing
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias e Instituto Andaluz de Biotecnología, Unidad asociada UMA-CSIC, Universidad de Málaga. Campus de Teatinos, 29071 Málaga, Spain
| | - Fernando Gallardo
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias e Instituto Andaluz de Biotecnología, Unidad asociada UMA-CSIC, Universidad de Málaga. Campus de Teatinos, 29071 Málaga, Spain
| | - María Belén Pascual
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias e Instituto Andaluz de Biotecnología, Unidad asociada UMA-CSIC, Universidad de Málaga. Campus de Teatinos, 29071 Málaga, Spain
| | - Rafael Sampalo
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias e Instituto Andaluz de Biotecnología, Unidad asociada UMA-CSIC, Universidad de Málaga. Campus de Teatinos, 29071 Málaga, Spain
| | - José Romero
- Apliforesta Internacional S.L., Parque Tecnológico de Andalucía, Edificio Bic Euronova, Campanillas, 29590 Málaga, Spain
| | - Augusto Torres De Navarra
- Apliforesta Internacional S.L., Parque Tecnológico de Andalucía, Edificio Bic Euronova, Campanillas, 29590 Málaga, Spain
| | - Francisco M Cánovas
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias e Instituto Andaluz de Biotecnología, Unidad asociada UMA-CSIC, Universidad de Málaga. Campus de Teatinos, 29071 Málaga, Spain
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Meuriot F, Noquet C, Avice JC, Volenec JJ, Cunningham SM, Sors TG, Caillot S, Ourry A. Methyl jasmonate alters N partitioning, N reserves accumulation and induces gene expression of a 32-kDa vegetative storage protein that possesses chitinase activity in Medicago sativa taproots. PHYSIOLOGIA PLANTARUM 2004; 120:113-123. [PMID: 15032883 DOI: 10.1111/j.0031-9317.2004.0210.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
This study presents the effects of methyl jasmonate (MeJA) on growth, N uptake, N partitioning, and N storage in taproots of non-nodulated alfalfa (cv. Lodi). When compared to untreated plants, addition of 100 micro M MeJA to the nutrient solution for 14 days reduced total growth and modified biomass partitioning between shoots and roots in favour of taproots and lateral roots. MeJA decreased N uptake (after 7 days) and increased N partitioning towards roots after 14 days. This preferential N partitioning to roots was accompanied by increased N storage in taproots as soluble proteins. Compared to total soluble proteins, VSP accumulation occurred earlier (7 days), and was greater (2-fold increase) in plants treated with 100 micro M MeJA. Steady-state transcript levels for two VSPs (32 and 57 kDa) also increased markedly (about 4-fold) in roots of plants treated with 100 micro M MeJA. This suggests that MeJA could act directly (transcriptional regulation) or indirectly (via the changes of N partitioning among alfalfa organs) on N storage as soluble proteins and in particular, VSPs. Because the deduced amino acid sequence of the 32 kDa VSP clone reveals high homology with Class III chitinases, we propose that the 32 kDa VSP may have a role in pathogen defense, in addition to its function as a storage protein.
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Affiliation(s)
- Frédéric Meuriot
- UMR INRA UCBN 950 Physiologie et Biochimie Végétales, Institut de Recherche en Biologie Appliquée, Université, 14032 Caen Cedex, France Department of Agronomy, Purdue University, West Lafayette, IN 47907-1150, USA
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Avice JC, Dily FL, Goulas E, Noquet C, Meuriot F, Volenec JJ, Cunningham SM, Sors TG, Dhont C, Castonguay Y, Nadeau P, Bélanger G, Chalifour FP, Ourry A. Vegetative storage proteins in overwintering storage organs of forage legumes: roles and regulation. ACTA ACUST UNITED AC 2003. [DOI: 10.1139/b03-122] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In perennial forage legumes such as alfalfa (Medicago sativa L.) and white clover (Trifolium repens L.), vegetative storage proteins are extensively mobilized to meet the nitrogen requirements of new shoot growth in spring or after cutting in summer. The 32-kDa alfalfa storage protein possesses high homology with class III chitinases, belonging to a group of pathogenesis-related proteins that possess antifreeze protein properties in some species and exhibit chitinolytic activity in vitro. This protein and the corresponding mRNA accumulate in taproots of cold-hardy culti vars during acclimation for winter, and in response to short-day conditions in controlled environments. The 17.3-kDa storage protein of white clover possesses high homology with pathogenesis-related proteins and abscisic- acid-responsive proteins from several legume species and has characteristics common to stress-responsive proteins. Low temperature enhances accumulation of this 17.3-kDa protein and its corresponding transcript. Exogenous abscisic acid stimulates the accumulation of vegetative storage proteins and their transcripts in both legume species. These observations suggest that vegetative storage proteins do not exclusively serve as nitrogen reserves during specific phases of legume development, but may play important adaptive roles in plant protection against abiotic (low temperature) and biotic (pathogen attack) stresses.Key words: nitrogen reserves, vegetative storage proteins, regulation, cold tolerance, chitinase, pathogenesis-related proteins.
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Tian WM, Wu JL, Hao BZ, Hu ZH. Vegetative storage proteins in the tropical tree Swietenia macrophylla: seasonal fluctuation in relation to a fundamental role in the regulation of tree growth. ACTA ACUST UNITED AC 2003. [DOI: 10.1139/b03-045] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The protein-storing cells in Swietenia macrophylla King were investigated. They were found to be of the Populus type, i.e., ordinary parenchyma cells containing both vacuole protein inclusion and starch grains. Vegetative storage proteins with molecular masses of 18 and 21 kDa were separated by SDSPAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis). Immunoblotting with the 21-kDa protein antiserum showed that the 18- and 21-kDa proteins shared common epitopes. The 21-kDa protein and presumably the 18-kDa protein were demonstrated by immunogold labeling to be the main components of the vacuole protein inclusion of the protein-storing cells. At the late stage of an annual growth cycle, vegetative storage proteins were found in the branchlets, trunk, large roots, and small roots. They were stored in large amounts in the secondary phloem of these organs and also in the secondary xylem of the terminal branchlets and small roots. In a new growth cycle, the consumption of the previously accumulated vegetative storage proteins began in the terminal branchlets of the last growth cycle. The vegetative storage proteins in the branchlets were exhausted completely when the new shoot leaves matured, while the storage proteins in the trunk and large roots had no detectable changes in abundance. On the other hand, the tree started to accumulate the two proteins in the stem of the new shoots as early as 1 week after the new shoot leaves matured. These results suggested that the previously accumulated vegetative storage proteins were used for new shoot growth and cambial activity in preference to the newly assimilated nitrogen and that vegetative storage proteins existed in considerable amounts in the stems throughout an annual growth cycle. This seasonal fluctuating pattern of vegetative storage proteins in the whole tree may be an important mechanism by which the tree regulates its growth.Key words: vegetative storage proteins, nitrogen metabolism, Populus-type of protein-storing cells, tropical hardwoods, Swietenia macrophylla King.
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