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Ricachenevsky FK, Punshon T, Lee S, Oliveira BHN, Trenz TS, Maraschin FDS, Hindt MN, Danku J, Salt DE, Fett JP, Guerinot ML. Elemental Profiling of Rice FOX Lines Leads to Characterization of a New Zn Plasma Membrane Transporter, OsZIP7. Front Plant Sci 2018; 9:865. [PMID: 30018622 PMCID: PMC6037872 DOI: 10.3389/fpls.2018.00865] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/04/2018] [Indexed: 05/07/2023]
Abstract
Iron (Fe) and zinc (Zn) are essential micronutrients required for proper development in both humans and plants. Rice (Oryza sativa L.) grains are the staple food for nearly half of the world's population, but a poor source of metals such as Fe and Zn. Populations that rely on milled cereals are especially prone to Fe and Zn deficiencies, the most prevalent nutritional deficiencies in humans. Biofortification is a cost-effective solution for improvement of the nutritional quality of crops. However, a better understanding of the mechanisms underlying grain accumulation of mineral nutrients is required before this approach can achieve its full potential. Characterization of gene function is more time-consuming in crops than in model species such as Arabidopsis thaliana. Aiming to more quickly characterize rice genes related to metal homeostasis, we applied the concept of high throughput elemental profiling (ionomics) to Arabidopsis lines heterologously expressing rice cDNAs driven by the 35S promoter, named FOX (Full Length Over-eXpressor) lines. We screened lines expressing candidate genes that could be used in the development of biofortified grain. Among the most promising candidates, we identified two lines ovexpressing the metal cation transporter OsZIP7. OsZIP7 expression in Arabidopsis resulted in a 25% increase in shoot Zn concentrations compared to non-transformed plants. We further characterized OsZIP7 and showed that it is localized to the plasma membrane and is able to complement Zn transport defective (but not Fe defective) yeast mutants. Interestingly, we showed that OsZIP7 does not transport Cd, which is commonly transported by ZIP proteins. Importantly, OsZIP7-expressing lines have increased Zn concentrations in their seeds. Our results indicate that OsZIP7 is a good candidate for developing Zn biofortified rice. Moreover, we showed the use of heterologous expression of genes from crops in A. thaliana as a fast method for characterization of crop genes related to the ionome and potentially useful in biofortification strategies.
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Affiliation(s)
- Felipe K. Ricachenevsky
- Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Departamento de Biologia, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria, Brazil
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States
- *Correspondence: Felipe K. Ricachenevsky,
| | - Tracy Punshon
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States
| | - Sichul Lee
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, South Korea
| | - Ben Hur N. Oliveira
- Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Thomaz S. Trenz
- Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Maria N. Hindt
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States
| | - John Danku
- School of Biosciences, University of Nottingham, Loughborough, United Kingdom
| | - David E. Salt
- School of Biosciences, University of Nottingham, Loughborough, United Kingdom
| | - Janette P. Fett
- Programa de Pós-Graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Mary Lou Guerinot
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States
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Campos ACAL, Kruijer W, Alexander R, Akkers RC, Danku J, Salt DE, Aarts MGM. Natural variation in Arabidopsis thaliana reveals shoot ionome, biomass, and gene expression changes as biomarkers for zinc deficiency tolerance. J Exp Bot 2017; 68:3643-3656. [PMID: 28859376 DOI: 10.1093/jxb/erx191] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 05/20/2017] [Indexed: 05/12/2023]
Abstract
Zinc (Zn) is an essential nutrient for plants, with a crucial role as a cofactor for many enzymes. Approximately one-third of the global arable land area is Zn deficient, leading to reduced crop yield and quality. To improve crop tolerance to Zn deficiency, it is important to understand the mechanisms plants have adopted to tolerate suboptimal Zn supply. In this study, physiological and molecular aspects of traits related to Zn deficiency tolerance were examined in a panel of 19 Arabidopsis thaliana accessions. Accessions showed a larger variation for shoot biomass than for Zn concentration, indicating that they have different requirements for their minimal Zn concentration required for growth. Accessions with a higher tolerance to Zn deficiency showed an increased expression of the Zn deficiency-responsive genes ZIP4 and IRT3 in comparison with Zn deficiency-sensitive accessions. Changes in the shoot ionome, as a result of the Zn treatment of the plants, were used to build a multinomial logistic regression model able to distinguish plants regarding their Zn nutritional status. This set of biomarkers, reflecting the A. thaliana response to Zn deficiency and Zn deficiency tolerance, can be useful for future studies aiming to improve the performance and Zn status of crop plants grown under suboptimal Zn concentrations.
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Affiliation(s)
- Ana Carolina A L Campos
- Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, Aberdeen AB24 3UU, UK
| | - Willem Kruijer
- Biometris, Wageningen University and Research, PO Box 100, 6700AC Wageningen, The Netherlands
| | - Ross Alexander
- Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
- School of Life Sciences, John Muir Building, Heriot Watt University, Edinburgh EH14 4AS, UK
| | - Robert C Akkers
- Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - John Danku
- Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, Aberdeen AB24 3UU, UK
| | - David E Salt
- Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, Aberdeen AB24 3UU, UK
| | - Mark G M Aarts
- Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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Huang XY, Chao DY, Koprivova A, Danku J, Wirtz M, Müller S, Sandoval FJ, Bauwe H, Roje S, Dilkes B, Hell R, Kopriva S, Salt DE. Nuclear Localised MORE SULPHUR ACCUMULATION1 Epigenetically Regulates Sulphur Homeostasis in Arabidopsis thaliana. PLoS Genet 2016; 12:e1006298. [PMID: 27622452 PMCID: PMC5021336 DOI: 10.1371/journal.pgen.1006298] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/12/2016] [Indexed: 12/25/2022] Open
Abstract
Sulphur (S) is an essential element for all living organisms. The uptake, assimilation and metabolism of S in plants are well studied. However, the regulation of S homeostasis remains largely unknown. Here, we report on the identification and characterisation of the more sulphur accumulation1 (msa1-1) mutant. The MSA1 protein is localized to the nucleus and is required for both S-adenosylmethionine (SAM) production and DNA methylation. Loss of function of the nuclear localised MSA1 leads to a reduction in SAM in roots and a strong S-deficiency response even at ample S supply, causing an over-accumulation of sulphate, sulphite, cysteine and glutathione. Supplementation with SAM suppresses this high S phenotype. Furthermore, mutation of MSA1 affects genome-wide DNA methylation, including the methylation of S-deficiency responsive genes. Elevated S accumulation in msa1-1 requires the increased expression of the sulphate transporter genes SULTR1;1 and SULTR1;2 which are also differentially methylated in msa1-1. Our results suggest a novel function for MSA1 in the nucleus in regulating SAM biosynthesis and maintaining S homeostasis epigenetically via DNA methylation. Sulphur is an essential element for all living organisms including plants. Plants take up sulphur from the soil mainly in the form of inorganic sulphate. The uptake of sulphate and assimilation of sulphur have been well studied. However, the regulation of sulphur accumulation in plants remains largely unknown. In this study, we characterize the high leaf sulphur mutant more sulphur accumulation1 (msa1-1) and demonstrate the function of MSA1 in controlling sulphur accumulation in Arabidopsis thaliana. The MSA1 protein is localized to the nucleus and is required for the biosynthesis of S-adenosylmethionine (SAM) which is a universal methyl donor for many methylation reactions, including DNA methylation. Loss of function of MSA1 reduces the SAM level in roots and affects genome-wide DNA methylation, including the methylation of sulphate transporter genes. We show that the high sulphur phenotype of msa1-1 requires elevated expression of the sulphate transporter genes which are differentially methylated in msa1-1. Our results suggest a connection between sulphur homeostasis and DNA methylation that is mediated by MSA1.
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Affiliation(s)
- Xin-Yuan Huang
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Dai-Yin Chao
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Anna Koprivova
- Botanical Institute, Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, Cologne, Germany
| | - John Danku
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Markus Wirtz
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Steffen Müller
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Francisco J. Sandoval
- Institute of Biological Chemistry, Washington State University, Pullman, Washington, United States of America
| | - Hermann Bauwe
- Department of Plant Physiology, University of Rostock, Rostock, Germany
| | - Sanja Roje
- Institute of Biological Chemistry, Washington State University, Pullman, Washington, United States of America
| | - Brian Dilkes
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Rüdiger Hell
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Stanislav Kopriva
- Botanical Institute, Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, Cologne, Germany
| | - David E Salt
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, United Kingdom
- * E-mail:
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Romè C, Huang XY, Danku J, Salt DE, Sebastiani L. Expression of specific genes involved in Cd uptake, translocation, vacuolar compartmentalisation and recycling in Populus alba Villafranca clone. J Plant Physiol 2016; 202:83-91. [PMID: 27467553 DOI: 10.1016/j.jplph.2016.07.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 07/07/2016] [Accepted: 07/10/2016] [Indexed: 05/15/2023]
Abstract
Cadmium (Cd) is a heavy metal toxic to humans and its occurrence in soils represents a significant environmental problem. Poplar trees may provide one possible option to help remove Cd contamination from soil. However, before this is practicable, the ability of poplar to accumulate Cd needs to be enhanced. A better understanding of the genes involved in Cd accumulation in poplar would help to achieve this goal. Here, we monitored the expression of genes known to be involved in Cd uptake, accumulation and translocation from other species, in order to provide information on their potential role in Cd accumulation in poplar. Cd concentration in poplar was significantly higher in roots than in stem and leaves in Cd treated plants. Expression of the poplar homologues of IRT1, NRAMP and OPT3 was initially increased after exposure to Cd but reduced after longer term Cd exposure. Exposure to Cd also influenced the accumulation of Fe, Ca, Cu, Mg and Mn in poplar. In particular, Cd treated plants had a higher concentration of Fe, Ca, Cu, and Mg in leaves and stem compared to control plants after one day and one week of experiment; while in roots after one month Cd treated plants had a lower concentration of Mn, Fe, Cu, Co, and Mg.
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Affiliation(s)
- Chiara Romè
- BioLabs, Institute of Life Sciences, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, I-56127 Pisa, Italy
| | - Xin-Yuan Huang
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom
| | - John Danku
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom
| | - David E Salt
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom
| | - Luca Sebastiani
- BioLabs, Institute of Life Sciences, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, I-56127 Pisa, Italy.
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Forsberg SKG, Andreatta ME, Huang XY, Danku J, Salt DE, Carlborg Ö. The Multi-allelic Genetic Architecture of a Variance-Heterogeneity Locus for Molybdenum Concentration in Leaves Acts as a Source of Unexplained Additive Genetic Variance. PLoS Genet 2015; 11:e1005648. [PMID: 26599497 PMCID: PMC4657900 DOI: 10.1371/journal.pgen.1005648] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 10/14/2015] [Indexed: 12/17/2022] Open
Abstract
Genome-wide association (GWA) analyses have generally been used to detect individual loci contributing to the phenotypic diversity in a population by the effects of these loci on the trait mean. More rarely, loci have also been detected based on variance differences between genotypes. Several hypotheses have been proposed to explain the possible genetic mechanisms leading to such variance signals. However, little is known about what causes these signals, or whether this genetic variance-heterogeneity reflects mechanisms of importance in natural populations. Previously, we identified a variance-heterogeneity GWA (vGWA) signal for leaf molybdenum concentrations in Arabidopsis thaliana. Here, fine-mapping of this association reveals that the vGWA emerges from the effects of three independent genetic polymorphisms that all are in strong LD with the markers displaying the genetic variance-heterogeneity. By revealing the genetic architecture underlying this vGWA signal, we uncovered the molecular source of a significant amount of hidden additive genetic variation or “missing heritability”. Two of the three polymorphisms underlying the genetic variance-heterogeneity are promoter variants for Molybdate transporter 1 (MOT1), and the third a variant located ~25 kb downstream of this gene. A fourth independent association was also detected ~600 kb upstream of MOT1. Use of a T-DNA knockout allele highlights Copper Transporter 6; COPT6 (AT2G26975) as a strong candidate gene for this association. Our results show that an extended LD across a complex locus including multiple functional alleles can lead to a variance-heterogeneity between genotypes in natural populations. Further, they provide novel insights into the genetic regulation of ion homeostasis in A. thaliana, and empirically confirm that variance-heterogeneity based GWA methods are a valuable tool to detect novel associations of biological importance in natural populations. Most biological traits vary in natural populations, and understanding the genetic basis of this variation remains an important challenge. Genome-wide association (GWA) studies have emerged as a powerful tool to address this challenge by dissecting the genetic architecture of trait variation into the contribution of individual genes. This contribution has traditionally been measured as the difference in the phenotypic means between groups of individuals with alternative genotypes at one, or multiple loci. However, instead of altering the trait mean, certain loci alter the variability of the trait. Here, we describe the genetic dissection of one such variance-controlling locus that drives variation in leaf molybdenum concentrations amongst natural accessions of Arabidopsis thaliana. The variance-controlling locus was found to result from the contributions of multiple alleles at multiple loci that are closely linked on the chromosome and is a major contributor to the “missing heritability” for this trait identified in previous studies. This illustrates that multi-allelic genetic architectures can hide large amounts of additive genetic variation, and that it is possible to uncover this hidden variation using the appropriate experimental designs and statistical methods described here.
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Affiliation(s)
- Simon K. G. Forsberg
- Department of Clinical Sciences, Division of Computational Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Matthew E. Andreatta
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Xin-Yuan Huang
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - John Danku
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - David E. Salt
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom
| | - Örjan Carlborg
- Department of Clinical Sciences, Division of Computational Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
- * E-mail:
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Busoms S, Teres J, Huang XY, Bomblies K, Danku J, Douglas A, Weigel D, Poschenrieder C, Salt DE. Salinity Is an Agent of Divergent Selection Driving Local Adaptation of Arabidopsis to Coastal Habitats. Plant Physiol 2015; 168:915-29. [PMID: 26034264 PMCID: PMC4741335 DOI: 10.1104/pp.15.00427] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 06/01/2015] [Indexed: 05/18/2023]
Abstract
Understanding the molecular mechanism of adaptive evolution in plants provides insights into the selective forces driving adaptation and the genetic basis of adaptive traits with agricultural value. The genomic resources available for Arabidopsis (Arabidopsis thaliana) make it well suited to the rapid molecular dissection of adaptive processes. Although numerous potentially adaptive loci have been identified in Arabidopsis, the consequences of divergent selection and migration (both important aspects of the process of local adaptation) for Arabidopsis are not well understood. Here, we use a multiyear field-based reciprocal transplant experiment to detect local populations of Arabidopsis composed of multiple small stands of plants (demes) that are locally adapted to the coast and adjacent inland habitats in northeastern Spain. We identify fitness tradeoffs between plants from these different habitats when grown together in inland and coastal common gardens and also, under controlled conditions in soil excavated from coastal and inland sites. Plants from the coastal habitat also outperform those from inland when grown under high salinity, indicating local adaptation to soil salinity. Sodium can be toxic to plants, and we find its concentration to be elevated in soil and plants sampled at the coast. We conclude that the local adaptation that we observe between adjacent coastal and inland populations is caused by ongoing divergent selection driven by the differential salinity between coastal and inland soils.
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Affiliation(s)
- Silvia Busoms
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - Joana Teres
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - Xin-Yuan Huang
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - Kirsten Bomblies
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - John Danku
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - Alex Douglas
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - Detlef Weigel
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - Charlotte Poschenrieder
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
| | - David E Salt
- Plant Physiology Laboratory, Bioscience Faculty, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain (S.B., J.T., C.P.);Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (X.-Y.H., J.D., A.D., D.E.S.); andMax Planck Institute for Developmental Biology, 72076 Tuebingen, Germany (K.B., D.W.)
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Chao DY, Baraniecka P, Danku J, Koprivova A, Lahner B, Luo H, Yakubova E, Dilkes B, Kopriva S, Salt DE. Variation in sulfur and selenium accumulation is controlled by naturally occurring isoforms of the key sulfur assimilation enzyme ADENOSINE 5'-PHOSPHOSULFATE REDUCTASE2 across the Arabidopsis species range. Plant Physiol 2014; 166:1593-608. [PMID: 25245030 PMCID: PMC4226352 DOI: 10.1104/pp.114.247825] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Natural variation allows the investigation of both the fundamental functions of genes and their role in local adaptation. As one of the essential macronutrients, sulfur is vital for plant growth and development and also for crop yield and quality. Selenium and sulfur are assimilated by the same process, and although plants do not require selenium, plant-based selenium is an important source of this essential element for animals. Here, we report the use of linkage mapping in synthetic F2 populations and complementation to investigate the genetic architecture of variation in total leaf sulfur and selenium concentrations in a diverse set of Arabidopsis (Arabidopsis thaliana) accessions. We identify in accessions collected from Sweden and the Czech Republic two variants of the enzyme ADENOSINE 5'-PHOSPHOSULFATE REDUCTASE2 (APR2) with strongly diminished catalytic capacity. APR2 is a key enzyme in both sulfate and selenate reduction, and its reduced activity in the loss-of-function allele apr2-1 and the two Arabidopsis accessions Hodonín and Shahdara leads to a lowering of sulfur flux from sulfate into the reduced sulfur compounds, cysteine and glutathione, and into proteins, concomitant with an increase in the accumulation of sulfate in leaves. We conclude from our observation, and the previously identified weak allele of APR2 from the Shahdara accession collected in Tadjikistan, that the catalytic capacity of APR2 varies by 4 orders of magnitude across the Arabidopsis species range, driving significant differences in sulfur and selenium metabolism. The selective benefit, if any, of this large variation remains to be explored.
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Affiliation(s)
- Dai-Yin Chao
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Patrycja Baraniecka
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - John Danku
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Anna Koprivova
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Brett Lahner
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Hongbing Luo
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Elena Yakubova
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Brian Dilkes
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - Stanislav Kopriva
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
| | - David E Salt
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom (D.-Y.C., J.D., D.E.S.);Department of Metabolic Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom (P.B., A.K., S.K.); andDepartment of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907 (B.L., H.L., E.Y., B.D.)
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8
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Zhai Z, Gayomba SR, Jung HI, Vimalakumari NK, Piñeros M, Craft E, Rutzke MA, Danku J, Lahner B, Punshon T, Guerinot ML, Salt DE, Kochian LV, Vatamaniuk OK. OPT3 Is a Phloem-Specific Iron Transporter That Is Essential for Systemic Iron Signaling and Redistribution of Iron and Cadmium in Arabidopsis. Plant Cell 2014; 26:2249-2264. [PMID: 24867923 PMCID: PMC4079381 DOI: 10.1105/tpc.114.123737] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 03/31/2014] [Accepted: 04/22/2014] [Indexed: 05/18/2023]
Abstract
Iron is essential for both plant growth and human health and nutrition. Knowledge of the signaling mechanisms that communicate iron demand from shoots to roots to regulate iron uptake as well as the transport systems mediating iron partitioning into edible plant tissues is critical for the development of crop biofortification strategies. Here, we report that OPT3, previously classified as an oligopeptide transporter, is a plasma membrane transporter capable of transporting transition ions in vitro. Studies in Arabidopsis thaliana show that OPT3 loads iron into the phloem, facilitates iron recirculation from the xylem to the phloem, and regulates both shoot-to-root iron signaling and iron redistribution from mature to developing tissues. We also uncovered an aspect of crosstalk between iron homeostasis and cadmium partitioning that is mediated by OPT3. Together, these discoveries provide promising avenues for targeted strategies directed at increasing iron while decreasing cadmium density in the edible portions of crops and improving agricultural productivity in iron deficient soils.
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Affiliation(s)
- Zhiyang Zhai
- Department of Crop and Soil Sciences, Cornell University, Ithaca, New York 14853
| | - Sheena R Gayomba
- Department of Crop and Soil Sciences, Cornell University, Ithaca, New York 14853
| | - Ha-Il Jung
- Department of Crop and Soil Sciences, Cornell University, Ithaca, New York 14853
| | | | - Miguel Piñeros
- Robert W. Holley Center for Agriculture and Health, U.S. Department of Agriculture-Agricultural Research Service, Ithaca, New York 14853
| | - Eric Craft
- Robert W. Holley Center for Agriculture and Health, U.S. Department of Agriculture-Agricultural Research Service, Ithaca, New York 14853
| | - Michael A Rutzke
- Department of Crop and Soil Sciences, Cornell University, Ithaca, New York 14853 Robert W. Holley Center for Agriculture and Health, U.S. Department of Agriculture-Agricultural Research Service, Ithaca, New York 14853
| | - John Danku
- Institute of Biological and Environmental Sciences, University of Aberdeen, AS24 3UU Scotland, United Kingdom
| | - Brett Lahner
- Center for Plant Environmental Stress Physiology, Purdue University, West Lafayette, Indiana 47907
| | - Tracy Punshon
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755
| | - Mary Lou Guerinot
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755
| | - David E Salt
- Institute of Biological and Environmental Sciences, University of Aberdeen, AS24 3UU Scotland, United Kingdom
| | - Leon V Kochian
- Robert W. Holley Center for Agriculture and Health, U.S. Department of Agriculture-Agricultural Research Service, Ithaca, New York 14853
| | - Olena K Vatamaniuk
- Department of Crop and Soil Sciences, Cornell University, Ithaca, New York 14853
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9
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Kellermeier F, Armengaud P, Seditas TJ, Danku J, Salt DE, Amtmann A. Analysis of the Root System Architecture of Arabidopsis Provides a Quantitative Readout of Crosstalk between Nutritional Signals. Plant Cell 2014; 26:1480-1496. [PMID: 24692421 PMCID: PMC4036566 DOI: 10.1105/tpc.113.122101] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
As plant roots forage the soil for food and water, they translate a multifactorial input of environmental stimuli into a multifactorial developmental output that manifests itself as root system architecture (RSA). Our current understanding of the underlying regulatory network is limited because root responses have traditionally been studied separately for individual nutrient deficiencies. In this study, we quantified 13 RSA parameters of Arabidopsis thaliana in 32 binary combinations of N, P, K, S, and light. Analysis of variance showed that each RSA parameter was determined by a typical pattern of environmental signals and their interactions. P caused the most important single-nutrient effects, while N-effects were strongly light dependent. Effects of K and S occurred mostly through nutrient interactions in paired or multiple combinations. Several RSA parameters were selected for further analysis through mutant phenotyping, which revealed combinations of transporters, receptors, and kinases acting as signaling modules in K-N interactions. Furthermore, nutrient response profiles of individual RSA features across NPK combinations could be assigned to transcriptionally coregulated clusters of nutrient-responsive genes in the roots and to ionome patterns in the shoots. The obtained data set provides a quantitative basis for understanding how plants integrate multiple nutritional stimuli into complex developmental programs.
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Affiliation(s)
- Fabian Kellermeier
- Institute of Molecular, Cell, and Systems Biology, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Patrick Armengaud
- INRA, UMR1318 INRA-AgroParisTech, Institut Jean-Pierre Bourgin, INRA Centre de Versailles-Grignon, 78026 Versailles, France
| | - Triona J Seditas
- Institute of Molecular, Cell, and Systems Biology, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - John Danku
- Institute of Biological and Environmental Sciences, College of Life Sciences and Medicine, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom
| | - David E Salt
- Institute of Biological and Environmental Sciences, College of Life Sciences and Medicine, University of Aberdeen, Aberdeen AB24 3UU, United Kingdom
| | - Anna Amtmann
- Institute of Molecular, Cell, and Systems Biology, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
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10
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Gayomba SR, Jung HI, Yan J, Danku J, Rutzke MA, Bernal M, Krämer U, Kochian LV, Salt DE, Vatamaniuk OK. The CTR/COPT-dependent copper uptake and SPL7-dependent copper deficiency responses are required for basal cadmium tolerance in A. thaliana. Metallomics 2014; 5:1262-75. [PMID: 23835944 DOI: 10.1039/c3mt00111c] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Copper (Cu) homeostasis in plants is maintained by at least two mechanisms: (1) the miRNA-dependent reallocation of intracellular Cu among major Cu-enzymes and important energy-related functions; (2) the regulation of the expression of Cu transporters including members of the CTR/COPT family. These events are controlled by the transcription factor SPL7 in Arabidopsis thaliana. Cadmium (Cd), on the other hand, is a non-essential and a highly toxic metal that interferes with homeostasis of essential elements by competing for cellular binding sites. Whether Cd affects Cu homeostasis in plants is unknown. We found that Cd stimulates Cu accumulation in roots of A. thaliana and increases mRNA expression of three plasma membrane-localized Cu uptake transporters, COPT1, COPT2 and COPT6. Further analysis of Cd sensitivity of single and triple copt1copt2copt6 mutants, and transgenic plants ectopically expressing COPT6 suggested that Cu uptake is an essential component of Cd resistance in A. thaliana. Analysis of the contribution of the SPL7-dependent pathway to Cd-induced expression of COPT1, COPT2 and COPT6 showed that it occurs, in part, through mimicking the SPL7-dependent transcriptional Cu deficiency response. This response also involves components of the Cu reallocation system, miRNA398, FSD1, CSD1 and CSD2. Furthermore, seedlings of the spl7-1 mutant accumulate up to 2-fold less Cu in roots than the wild-type, are hypersensitive to Cd, and are more sensitive to Cd than the triple copt1copt2copt6 mutant. Together these data show that exposure to excess Cd triggers SPL7-dependent Cu deficiency responses that include Cu uptake and reallocation that are required for basal Cd tolerance in A. thaliana.
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Affiliation(s)
- Sheena R Gayomba
- Department of Crop and Soil Sciences, Cornell University, Ithaca, NY 14853, USA
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11
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Baxter IR, Ziegler G, Lahner B, Mickelbart MV, Foley R, Danku J, Armstrong P, Salt DE, Hoekenga OA. Single-kernel ionomic profiles are highly heritable indicators of genetic and environmental influences on elemental accumulation in maize grain (Zea mays). PLoS One 2014; 9:e87628. [PMID: 24489944 PMCID: PMC3906179 DOI: 10.1371/journal.pone.0087628] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 12/26/2013] [Indexed: 12/02/2022] Open
Abstract
The ionome, or elemental profile, of a maize kernel can be viewed in at least two distinct ways. First, the collection of elements within the kernel are food and feed for people and animals. Second, the ionome of the kernel represents a developmental end point that can summarize the life history of a plant, combining genetic programs and environmental interactions. We assert that single-kernel-based phenotyping of the ionome is an effective method of analysis, as it represents a reasonable compromise between precision, efficiency, and power. Here, we evaluate potential pitfalls of this sampling strategy using several field-grown maize sample sets. We demonstrate that there is enough genetically determined diversity in accumulation of many of the elements assayed to overcome potential artifacts. Further, we demonstrate that environmental signals are detectable through their influence on the kernel ionome. We conclude that using single kernels as the sampling unit is a valid approach for understanding genetic and environmental effects on the maize kernel ionome.
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Affiliation(s)
- Ivan R. Baxter
- United States Department of Agriculture, Agricultural Research Service, Plant Genetics Research Unit, Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
| | - Gregory Ziegler
- United States Department of Agriculture, Agricultural Research Service, Plant Genetics Research Unit, Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
| | - Brett Lahner
- Purdue University, Department of Horticulture and Landscape Architecture, West Lafayette, Indiana, United States of America
| | - Michael V. Mickelbart
- Purdue University, Department of Horticulture and Landscape Architecture, West Lafayette, Indiana, United States of America
| | - Rachel Foley
- Purdue University, Department of Horticulture and Landscape Architecture, West Lafayette, Indiana, United States of America
| | - John Danku
- University of Aberdeen, Institute of Biological and Environmental Science, Aberdeen, United Kingdom
| | - Paul Armstrong
- United States Department of Agriculture, Agricultural Research Service, Engineering and Wind Erosion Research Unit, Manhattan, Kansas, United States of America
| | - David E. Salt
- University of Aberdeen, Institute of Biological and Environmental Science, Aberdeen, United Kingdom
| | - Owen A. Hoekenga
- United States Department of Agriculture, Agricultural Research Service, RW Holley Center for Agriculture and Health, Ithaca, New York, United States of America
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Hosmani PS, Kamiya T, Danku J, Naseer S, Geldner N, Guerinot ML, Salt DE. Dirigent domain-containing protein is part of the machinery required for formation of the lignin-based Casparian strip in the root. Proc Natl Acad Sci U S A 2013; 110:14498-14503. [PMID: 23940370 DOI: 10.1073/pnas.13084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023] Open
Abstract
The endodermis acts as a "second skin" in plant roots by providing the cellular control necessary for the selective entry of water and solutes into the vascular system. To enable such control, Casparian strips span the cell wall of adjacent endodermal cells to form a tight junction that blocks extracellular diffusion across the endodermis. This junction is composed of lignin that is polymerized by oxidative coupling of monolignols through the action of a NADPH oxidase and peroxidases. Casparian strip domain proteins (CASPs) correctly position this biosynthetic machinery by forming a protein scaffold in the plasma membrane at the site where the Casparian strip forms. Here, we show that the dirigent-domain containing protein, enhanced suberin1 (ESB1), is part of this machinery, playing an essential role in the correct formation of Casparian strips. ESB1 is localized to Casparian strips in a CASP-dependent manner, and in the absence of ESB1, disordered and defective Casparian strips are formed. In addition, loss of ESB1 disrupts the localization of the CASP1 protein at the casparian strip domain, suggesting a reciprocal requirement for both ESB1 and CASPs in forming the casparian strip domain.
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Affiliation(s)
- Prashant S Hosmani
- Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA
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Yu D, Danku J, Baxter I, Kim S, Vatamaniuk OK, Salt DE, Vitek O. Noise reduction in genome-wide perturbation screens using linear mixed-effect models. Bioinformatics 2011; 27:2173-80. [PMID: 21685046 PMCID: PMC3150043 DOI: 10.1093/bioinformatics/btr359] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 05/31/2011] [Accepted: 06/08/2011] [Indexed: 11/12/2022] Open
Abstract
MOTIVATION High-throughput perturbation screens measure the phenotypes of thousands of biological samples under various conditions. The phenotypes measured in the screens are subject to substantial biological and technical variation. At the same time, in order to enable high throughput, it is often impossible to include a large number of replicates, and to randomize their order throughout the screens. Distinguishing true changes in the phenotype from stochastic variation in such experimental designs is extremely challenging, and requires adequate statistical methodology. RESULTS We propose a statistical modeling framework that is based on experimental designs with at least two controls profiled throughout the experiment, and a normalization and variance estimation procedure with linear mixed-effects models. We evaluate the framework using three comprehensive screens of Saccharomyces cerevisiae, which involve 4940 single-gene knock-out haploid mutants, 1127 single-gene knock-out diploid mutants and 5798 single-gene overexpression haploid strains. We show that the proposed approach (i) can be used in conjunction with practical experimental designs; (ii) allows extensions to alternative experimental workflows; (iii) enables a sensitive discovery of biologically meaningful changes; and (iv) strongly outperforms the existing noise reduction procedures. AVAILABILITY All experimental datasets are publicly available at www.ionomicshub.org. The R package HTSmix is available at http://www.stat.purdue.edu/~ovitek/HTSmix.html. CONTACT ovitek@stat.purdue.edu SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Danni Yu
- Department of Statistics, Purdue University, West Lafayette, IN 47907, USA
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Baxter I, Muthukumar B, Park HC, Buchner P, Lahner B, Danku J, Zhao K, Lee J, Hawkesford MJ, Guerinot ML, Salt DE. Variation in molybdenum content across broadly distributed populations of Arabidopsis thaliana is controlled by a mitochondrial molybdenum transporter (MOT1). PLoS Genet 2008; 4:e1000004. [PMID: 18454190 PMCID: PMC2265440 DOI: 10.1371/journal.pgen.1000004] [Citation(s) in RCA: 197] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Accepted: 01/17/2008] [Indexed: 11/19/2022] Open
Abstract
Molybdenum (Mo) is an essential micronutrient for plants, serving as a cofactor for enzymes involved in nitrate assimilation, sulfite detoxification, abscisic acid biosynthesis, and purine degradation. Here we show that natural variation in shoot Mo content across 92 Arabidopsis thaliana accessions is controlled by variation in a mitochondrially localized transporter (Molybdenum Transporter 1 - MOT1) that belongs to the sulfate transporter superfamily. A deletion in the MOT1 promoter is strongly associated with low shoot Mo, occurring in seven of the accessions with the lowest shoot content of Mo. Consistent with the low Mo phenotype, MOT1 expression in low Mo accessions is reduced. Reciprocal grafting experiments demonstrate that the roots of Ler-0 are responsible for the low Mo accumulation in shoot, and GUS localization demonstrates that MOT1 is expressed strongly in the roots. MOT1 contains an N-terminal mitochondrial targeting sequence and expression of MOT1 tagged with GFP in protoplasts and transgenic plants, establishing the mitochondrial localization of this protein. Furthermore, expression of MOT1 specifically enhances Mo accumulation in yeast by 5-fold, consistent with MOT1 functioning as a molybdate transporter. This work provides the first molecular insight into the processes that regulate Mo accumulation in plants and shows that novel loci can be detected by association mapping.
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Affiliation(s)
- Ivan Baxter
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
| | - Balasubramaniam Muthukumar
- Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United States of America
| | - Hyeong Cheol Park
- Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United States of America
| | - Peter Buchner
- Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Brett Lahner
- Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United States of America
| | - John Danku
- Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United States of America
| | - Keyan Zhao
- Molecular and Computational Biology, University of Southern California, Los Angeles, California, United States of America
| | - Joohyun Lee
- Biological Sciences, Dartmouth College, Hanover, New Hampshire, United States of America
| | | | - Mary Lou Guerinot
- Biological Sciences, Dartmouth College, Hanover, New Hampshire, United States of America
| | - David E. Salt
- Bindley Bioscience Center, Purdue University, West Lafayette, Indiana, United States of America
- Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United States of America
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