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Samarth, Lee R, Kelly D, Turnbull MH, Macknight RC, Poole AM, Jameson PE. Molecular control of the floral transition in the mast seeding plant Celmisia lyallii (Asteraceae). Mol Ecol 2021; 30:1846-1863. [PMID: 33624370 DOI: 10.1111/mec.15859] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 02/06/2021] [Accepted: 02/15/2021] [Indexed: 12/21/2022]
Abstract
Mast flowering (or masting) is synchronous, highly variable flowering among years in populations of perennial plants. Despite having widespread consequences for seed consumers, endangered fauna and human health, masting is hard to predict. While observational studies show links to various weather patterns in different plant species, the mechanism(s) underpinning the regulation of masting is still not fully explained. We studied floral induction in Celmisia lyallii (Asteraceae), a mast flowering herbaceous alpine perennial, comparing gene expression in flowering and nonflowering plants. We performed translocation experiments to induce the floral transition in C. lyallii plants followed by both global and targeted expression analysis of flowering-pathway genes. Differential expression analysis showed elevated expression of ClSOC1 and ClmiR172 (promoters of flowering) in leaves of plants that subsequently flowered, in contrast to elevated expression of ClAFT and ClTOE1 (repressors of flowering) in leaves of plants that did not flower. The warm summer conditions that promoted flowering led to differential regulation of age and hormonal pathway genes, including ClmiR172 and ClGA20ox2, known to repress the expression of floral repressors and permit flowering. Upregulated expression of epigenetic modifiers of floral promoters also suggests that plants may maintain a novel "summer memory" across years to induce flowering. These results provide a basic mechanistic understanding of floral induction in masting plants and evidence of their ability to imprint various environmental cues to synchronize flowering, allowing us to better predict masting events under climate change.
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Affiliation(s)
- Samarth
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Robyn Lee
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Dave Kelly
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Matthew H Turnbull
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | | | - Anthony M Poole
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand.,Bioinformatics Institute, School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Paula E Jameson
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
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Pérez-Llorca M, Munné-Bosch S. Aging, stress, and senescence in plants: what can biological diversity teach us? GeroScience 2021; 43:167-180. [PMID: 33590435 DOI: 10.1007/s11357-021-00336-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/03/2021] [Indexed: 11/25/2022] Open
Abstract
Aging, stress, and senescence in plants are interconnected processes that determine longevity. We focus here on compiling and discussing our current knowledge on the mechanisms of development that long-lived perennial plants have evolved to prevent and delay senescence. Clonal and nonclonal perennial herbs of various life forms and longevities will be particularly considered to illustrate what biological diversity can teach us about aging as a universal phenomenon. Source-sink relations and redox signaling will also be discussed as examples of regulatory mechanisms of senescence at the organ level. Whether or not effective mechanisms that biological diversity has evolved to completely prevent the wear and tear of aging will be applicable to human aging in the near future ultimately depends on ethical aspects.
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Affiliation(s)
- Marina Pérez-Llorca
- Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona, Spain.,Institute of Research in Biodiversity (IRBio), University of Barcelona, Barcelona, Spain
| | - Sergi Munné-Bosch
- Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona, Spain. .,Institute of Research in Biodiversity (IRBio), University of Barcelona, Barcelona, Spain.
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3
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Zhao X, Nie G, Yao Y, Ji Z, Gao J, Wang X, Jiang Y. Natural variation and genomic prediction of growth, physiological traits, and nitrogen-use efficiency in perennial ryegrass under low-nitrogen stress. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6670-6683. [PMID: 32827031 DOI: 10.1093/jxb/eraa388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
Genomic prediction of nitrogen-use efficiency (NUE) has not previously been studied in perennial grass species exposed to low-N stress. Here, we conducted a genomic prediction of physiological traits and NUE in 184 global accessions of perennial ryegrass (Lolium perenne) in response to a normal (7.5 mM) and low (0.75 mM) supply of N. After 21 d of treatment under greenhouse conditions, significant variations in plant height increment (ΔHT), leaf fresh weight (LFW), leaf dry weight (LDW), chlorophyll index (Chl), chlorophyll fluorescence, leaf N and carbon (C) contents, C/N ratio, and NUE were observed in accessions , but to a greater extent under low-N stress. Six genomic prediction models were applied to the data, namely the Bayesian method Bayes C, Bayesian LASSO, Bayesian Ridge Regression, Ridge Regression-Best Linear Unbiased Prediction, Reproducing Kernel Hilbert Spaces, and randomForest. These models produced similar prediction accuracy of traits within the normal or low-N treatments, but the accuracy differed between the two treatments. ΔHT, LFW, LDW, and C were predicted slightly better under normal N with a mean Pearson r-value of 0.26, compared with r=0.22 under low N, while the prediction accuracies for Chl, N, C/N, and NUE were significantly improved under low-N stress with a mean r=0.45, compared with r=0.26 under normal N. The population panel contained three population structures, which generally had no effect on prediction accuracy. The moderate prediction accuracies obtained for N, C, and NUE under low-N stress are promising, and suggest a feasible means by which germplasm might be initially assessed for further detailed studies in breeding programs.
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Affiliation(s)
- Xiongwei Zhao
- College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi Province, China
| | - Gang Nie
- Department of Grassland Science, Animal Science and Technology College, Sichuan Agricultural University, Chengdu, Sichuan Province, China
| | - Yanyu Yao
- Department of Agronomy, Purdue University, West Lafayette, IN, USA
| | - Zhongjie Ji
- Department of Agronomy, Purdue University, West Lafayette, IN, USA
| | - Jianhua Gao
- College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi Province, China
| | - Xingchun Wang
- College of Life Sciences, Shanxi Agricultural University, Taigu, Shanxi Province, China
| | - Yiwei Jiang
- Department of Agronomy, Purdue University, West Lafayette, IN, USA
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Dhanagond S, Liu G, Zhao Y, Chen D, Grieco M, Reif J, Kilian B, Graner A, Neumann K. Non-Invasive Phenotyping Reveals Genomic Regions Involved in Pre-Anthesis Drought Tolerance and Recovery in Spring Barley. FRONTIERS IN PLANT SCIENCE 2019; 10:1307. [PMID: 31708943 PMCID: PMC6823269 DOI: 10.3389/fpls.2019.01307] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 09/19/2019] [Indexed: 05/07/2023]
Abstract
With ongoing climate change, drought events are becoming more frequent and will affect biomass formation when occurring during pre-flowering stages. We explored growth over time under such a drought scenario, via non-invasive imaging and revealed the underlying key genetic factors in spring barley. By comparing with well-watered conditions investigated in an earlier study and including information on timing, QTL could be classified as constitutive, drought or recovery-adaptive. Drought-adaptive QTL were found in the vicinity of genes involved in dehydration tolerance such as dehydrins (Dhn4, Dhn7, Dhn8, and Dhn9) and aquaporins (e.g. HvPIP1;5, HvPIP2;7, and HvTIP2;1). The influence of phenology on biomass formation increased under drought. Accordingly, the main QTL during recovery was the region of HvPPD-H1. The most important constitutive QTL for late biomass was located in the vicinity of HvDIM, while the main locus for seedling biomass was the HvWAXY region. The disappearance of QTL marked the genetic architecture of tiller number. The most important constitutive QTL was located on 6HS in the region of 1-FEH. Stage and tolerance specific QTL might provide opportunities for genetic manipulation to stabilize biomass and tiller number under drought conditions and thereby also grain yield.
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Affiliation(s)
- Sidram Dhanagond
- Department of Genebank, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Guozheng Liu
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
- BBCC – Innovation Center Gent, Gent Zwijnaarde, Belgium
| | - Yusheng Zhao
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Dijun Chen
- Institute for Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Michele Grieco
- Department of Genebank, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
| | - Jochen Reif
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
- Plant Breeding Department, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Benjamin Kilian
- Department of Genebank, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
- Global Crop Diversity Trust (GCDT), Bonn, Germany
| | - Andreas Graner
- Department of Genebank, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
- Plant Breeding Department, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Kerstin Neumann
- Department of Genebank, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Seeland, Germany
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Lee R, Song J, Macknight RC, Jameson PE. Identification of flowering-time genes in mast flowering plants using De Novo transcriptomic analysis. PLoS One 2019; 14:e0216267. [PMID: 31412034 PMCID: PMC6693765 DOI: 10.1371/journal.pone.0216267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 07/22/2019] [Indexed: 11/18/2022] Open
Abstract
Mast flowering is synchronised highly variable flowering by a population of perennial plants over a wide geographical area. High seeding years are seen as a threat to native and endangered species due to high predator density caused by the abundance of seed. An understanding of the molecular pathways that influence masting behaviour in plants could provide better prediction of a forthcoming masting season and enable conservation strategies to be deployed. The goal of this study was to identify candidate flowering genes that might be involved in regulating mast flowering. To achieve this, high-throughput large-scale RNA-sequencing was performed on two masting plant species, Celmisia lyallii (Asteraceae), and Chionochloa pallens (Poaceae) to develop a reference transcriptome for functional and molecular analysis. An average total of 33 million 150 base-paired reads, for both species, were assembled using the Trinity pipeline, resulting in 151,803 and 348,649 transcripts respectively for C. lyallii and C. pallens. For both species, about 56% of the unigenes were annotated with gene descriptions to known proteins followed by Gene Ontology analysis, categorising them on the basis of putative biological processes, molecular function, and cellular localization. A total of 543 transcripts from C. lyallii and 470 transcripts from C. pallens were also mapped to unique flowering-time proteins identified in Arabidopsis thaliana, suggesting the conservation of the flowering network in these wild alpine plants growing in natural field conditions. Expression analysis of several selected homologous flowering-pathway genes showed seasonal and photoperiodic variations. These genes can further be analysed to understand why seasonal cues, such as the increasing photoperiod in spring, that triggers the annual flowering of most plants, are insufficient to always trigger flowering in masting plants and to uncover the molecular basis of how additional cues (such as temperature during the previous growing seasons) then determines flowering in mast years.
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Affiliation(s)
- Robyn Lee
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Jiancheng Song
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- School of Life Sciences, Yantai University, Yantai, China
| | | | - Paula E. Jameson
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- * E-mail: (PJ); (S)
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Gu J, Li Z, Mao Y, Struik PC, Zhang H, Liu L, Wang Z, Yang J. Roles of nitrogen and cytokinin signals in root and shoot communications in maximizing of plant productivity and their agronomic applications. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 274:320-331. [PMID: 30080619 DOI: 10.1016/j.plantsci.2018.06.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 06/13/2018] [Accepted: 06/13/2018] [Indexed: 05/03/2023]
Abstract
Nitrogen is an essential, often limiting, factor in plant growth and development. To regulate growth under limited nitrogen supply, plants sense the internal and external nitrogen status, and coordinate various metabolic processes and developmental programs accordingly. This coordination requires the transmission of various signaling molecules that move across the entire plant. Cytokinins, phytohormones derived from adenine and synthesized in various parts of the plant, are considered major local and long-distance messengers. Cytokinin metabolism and signaling are closely associated with nitrogen availability. They are systemically transported via the vasculature from plant roots to shoots, and vice versa, thereby coordinating shoot and root development. Tight linkage exists between the nitrogen signaling network and cytokinins during diverse developmental and physiological processes. However, the cytokinin-nitrogen interactions and the communication systems involved in sensing rhizospheric nitrogen status and in regulating canopy development remain obscure. We review current knowledge on cytokinin biosynthesis, transport and signaling, nitrogen acquisition, metabolism and signaling, and their interactive roles in regulating root-shoot morphological and physiological characteristics. We also discuss the role of spatio-temporal regulation of cytokinins in enhancing beneficial crop traits of yield and nitrogen use efficiency.
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Affiliation(s)
- Junfei Gu
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Zhikang Li
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Yiqi Mao
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Paul C Struik
- Centre for Crop Systems Analysis, Department of Plant Science, Wageningen University, PO Box 430, Wageningen, 6700 AK, The Netherlands
| | - Hao Zhang
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Lijun Liu
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Zhiqin Wang
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Jianchang Yang
- Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
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Roche J, Turnbull MH, Guo Q, Novák O, Späth J, Gieseg SP, Jameson PE, Love J. Coordinated nitrogen and carbon remobilization for nitrate assimilation in leaf, sheath and root and associated cytokinin signals during early regrowth of Lolium perenne. ANNALS OF BOTANY 2017; 119:1353-1364. [PMID: 28334245 PMCID: PMC5604574 DOI: 10.1093/aob/mcx014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 01/30/2017] [Indexed: 05/18/2023]
Abstract
Background and Aims The efficiency of N assimilation in response to defoliation is a critical component of plant regrowth and forage production. The aim of this research was to test the effect of the internal C/N balance on NO3- assimilation and to estimate the associated cytokinin signals following defoliation of perennial ryegrass ( Lolium perenne L. 'Grasslands Nui') plants. Methods Plants, manipulated to have contrasting internal N content and contrasting availability of water soluble carbohydrates (WSCs), were obtained by exposure to either continuous light or short days (8:16 h light-dark), and watered with modified N-free Hoagland medium containing either high (5 m m ) or low (50 μ m ) NO3- as sole N source. Half of the plants were defoliated and the root, sheath and leaf tissue were harvested at 8, 24 and 168 h after cutting. The spatiotemporal changes in WSCs, synthesis of amino acids and associated cytokinin content were recorded after cutting. Key Results Leaf regrowth following defoliation involved changes in the low- and high-molecular weight WSCs. The extent of the changes and the partitioning of the WSC following defoliation were dependant on the initial WSC levels and the C and N availability. Cytokinin levels varied in the sheath and root as early as 8 h following defoliation and preceded an overall increase in amino acids at 24 h. Subsequently, negative feedback brought the amino acid response back towards pre-defoliation levels within 168 h after cutting, a response that was under control of the C/N ratio. Conclusions WSC remobilization in the leaf is coordinated with N availability to the root, potentially via a systemic cytokinin signal, leading to efficient N assimilation in the leaf and the sheath tissues and to early leaf regrowth following defoliation.
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Affiliation(s)
- Jessica Roche
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Matthew H. Turnbull
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Qianqian Guo
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Ondřej Novák
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Jana Späth
- Swedish Metabolomics Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences KBC, Umeå University, Linnéus väg, SE-90182 Umeå, Sweden
| | - Steven P. Gieseg
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Paula E. Jameson
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Jonathan Love
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
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Guo Q, Turnbull MH, Song J, Roche J, Novak O, Späth J, Jameson PE, Love J. Depletion of carbohydrate reserves limits nitrate uptake during early regrowth in Lolium perenne L. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1569-1583. [PMID: 28379423 PMCID: PMC5444434 DOI: 10.1093/jxb/erx056] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The mechanisms linking C/N balance to N uptake and assimilation are central to plant responses to changing soil nutrient levels. Defoliation and subsequent regrowth of grasses both impact C partitioning, thereby creating a significant point of interaction with soil N availability. Using defoliation as an experimental treatment, we investigated the dynamic relationships between plant carbohydrate status and NO3--responsive uptake systems, transporter gene expression, and nitrate assimilation in Lolium perenne L. High- and low-affinity NO3- uptake was reduced in an N-dependent manner in response to a rapid and large shift in carbohydrate remobilization triggered by defoliation. This reduction in NO3- uptake was rescued by an exogenous glucose supplement, confirming the carbohydrate dependence of NO3- uptake. The regulation of NO3- uptake in response to the perturbation of the plant C/N ratio was associated with changes in expression of putative high- and low-affinity NO3- transporters. Furthermore, NO3- assimilation appears to be regulated by the C-N status of the plant, implying a mechanism that signals the availability of C metabolites for NO3- uptake and assimilation at the whole-plant level. We also show that cytokinins may be involved in the regulation of N acquisition and assimilation in response to the changing plant C/N ratio.
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Affiliation(s)
- Qianqian Guo
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Matthew Hamish Turnbull
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Jiancheng Song
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
- School of Life Sciences, Yantai University, Yantai 264005, China
| | - Jessica Roche
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Ondrej Novak
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Šlechtitelu 27, 783 71 Olomouc, Czech Republic
| | - Jana Späth
- Swedish Metabolomics Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences KBC, Umeå University, Linnéus väg 6, SE-90183 Umeå, Sweden
| | - Paula Elizabeth Jameson
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Jonathan Love
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
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Jameson PE, Dhandapani P, Novak O, Song J. Cytokinins and Expression of SWEET, SUT, CWINV and AAP Genes Increase as Pea Seeds Germinate. Int J Mol Sci 2016; 17:E2013. [PMID: 27916945 PMCID: PMC5187813 DOI: 10.3390/ijms17122013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 11/24/2016] [Accepted: 11/25/2016] [Indexed: 02/06/2023] Open
Abstract
Transporter genes and cytokinins are key targets for crop improvement. These genes are active during the development of the seed and its establishment as a strong sink. However, during germination, the seed transitions to being a source for the developing root and shoot. To determine if the sucrose transporter (SUT), amino acid permease (AAP), Sugar Will Eventually be Exported Transporter (SWEET), cell wall invertase (CWINV), cytokinin biosynthesis (IPT), activation (LOG) and degradation (CKX) gene family members are involved in both the sink and source activities of seeds, we used RT-qPCR to determine the expression of multiple gene family members, and LC-MS/MS to ascertain endogenous cytokinin levels in germinating Pisum sativum L. We show that genes that are actively expressed when the seed is a strong sink during its development, are also expressed when the seed is in the reverse role of being an active source during germination and early seedling growth. Cytokinins were detected in the imbibing seeds and were actively biosynthesised during germination. We conclude that, when the above gene family members are targeted for seed yield improvement, a downstream effect on subsequent seed germination or seedling vigour must be taken into consideration.
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Affiliation(s)
- Paula E Jameson
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
| | - Pragatheswari Dhandapani
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
| | - Ondrej Novak
- Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany CAS & Faculty of Science of Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
| | - Jiancheng Song
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
- School of Life Sciences, Yantai University, Yantai 264005, China.
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