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Tapia G, González M, Burgos J, Vega MV, Méndez J, Inostroza L. Early transcriptional responses in Solanum peruvianum and Solanum lycopersicum account for different acclimation processes during water scarcity events. Sci Rep 2021; 11:15961. [PMID: 34354211 PMCID: PMC8342453 DOI: 10.1038/s41598-021-95622-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 07/27/2021] [Indexed: 12/13/2022] Open
Abstract
Cultivated tomato Solanum lycopersicum (Slyc) is sensitive to water shortages, while its wild relative Solanum peruvianum L. (Sper), an herbaceous perennial small shrub, can grow under water scarcity and soil salinity environments. Plastic Sper modifies the plant architecture when suffering from drought, which is mediated by the replacement of leaf organs, among other changes. The early events that trigger acclimation and improve these morphological traits are unknown. In this study, a physiological and transcriptomic approach was used to understand the processes that differentiate the response in Slyc and Sper in the context of acclimation to stress and future consequences for plant architecture. In this regard, moderate (MD) and severe drought (SD) were imposed, mediating PEG treatments. The results showed a reduction in water and osmotic potential during stress, which correlated with the upregulation of sugar and proline metabolism-related genes. Additionally, the senescence-related genes FTSH6 protease and asparagine synthase were highly induced in both species. However, GO categories such as "protein ubiquitination" or "endopeptidase inhibitor activity" were differentially enriched in Sper and Slyc, respectively. Genes related to polyamine biosynthesis were induced, while several cyclins and kinetin were downregulated in Sper under drought treatments. Repression of photosynthesis-related genes was correlated with a higher reduction in the electron transport rate in Slyc than in Sper. Additionally, transcription factors from the ERF, WRKY and NAC families were commonly induced in Sper. Although some similar responses were induced in both species under drought stress, many important changes were detected to be differentially induced. This suggests that different pathways dictate the strategies to address the early response to drought and the consequent episodes in the acclimation process in both tomato species.
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Affiliation(s)
- G Tapia
- Unidad de Recursos Genéticos Vegetales, Instituto de Investigaciones Agropecuarias, INIA-Quilamapu, Avenida Vicente Mendez 515, Chillán, Chile.
| | - M González
- Laboratorio de Microbiología Aplicada, Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Raúl Bitrán 1305, La Serena, Chile
| | - J Burgos
- Unidad de Recursos Genéticos Vegetales, Instituto de Investigaciones Agropecuarias, INIA-Quilamapu, Avenida Vicente Mendez 515, Chillán, Chile
| | - M V Vega
- Unidad de Recursos Genéticos Vegetales, Instituto de Investigaciones Agropecuarias, INIA-Quilamapu, Avenida Vicente Mendez 515, Chillán, Chile
| | - J Méndez
- Unidad de Recursos Genéticos Vegetales, Instituto de Investigaciones Agropecuarias, INIA-Quilamapu, Avenida Vicente Mendez 515, Chillán, Chile
| | - L Inostroza
- Unidad de Recursos Genéticos Vegetales, Instituto de Investigaciones Agropecuarias, INIA-Quilamapu, Avenida Vicente Mendez 515, Chillán, Chile
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2
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Tsamir-Rimon M, Ben-Dor S, Feldmesser E, Oppenhimer-Shaanan Y, David-Schwartz R, Samach A, Klein T. Rapid starch degradation in the wood of olive trees under heat and drought is permitted by three stress-specific beta amylases. THE NEW PHYTOLOGIST 2021; 229:1398-1414. [PMID: 32880972 DOI: 10.1111/nph.16907] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 06/02/2020] [Indexed: 06/11/2023]
Abstract
Carbon reserve use is a major drought response in trees, enabling tree survival in conditions prohibiting photosynthesis. However, regulation of starch metabolism under drought at the whole-tree scale is still poorly understood. To this end, we combined measurements of nonstructural carbohydrates (NSCs), tree physiology and gene expression. The experiment was conducted outside on olive trees in pots under 90 d of seasonal spring to summer warming. Half of the trees were also subjected to limited water conditions for 28 d. Photosynthesis decreased in dehydrating trees from 19 to 0.5 µmol m-2 s-1 during the drought period. Starch degradation and mannitol production were a major drought response, with mannitol increasing to 71% and 41% out of total NSCs in shoots and roots, respectively. We identified the gene family members potentially relevant either to long-term or stress-induced carbon storage. Partitioning of expression patterns among β amylase and starch synthase family members was observed, with three β amylases possibly facilitating the rapid starch degradation under heat and drought. Our results suggest a group of stress-related, starch metabolism genes, correlated with NSC fluctuations during drought and recovery. The daily starch metabolism gene expression was different from the stress-mode starch metabolism pattern, where some genes are uniquely expressed during the stress-mode response.
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Affiliation(s)
- Mor Tsamir-Rimon
- Plant & Environmental Sciences Department, Weizmann Institute of Science, Rehovot, 76100, Israel
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Shifra Ben-Dor
- Life Science Core Facilities, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Ester Feldmesser
- Life Science Core Facilities, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Yaara Oppenhimer-Shaanan
- Plant & Environmental Sciences Department, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Rakefet David-Schwartz
- Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion, 7505101, Israel
| | - Alon Samach
- The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel
| | - Tamir Klein
- Plant & Environmental Sciences Department, Weizmann Institute of Science, Rehovot, 76100, Israel
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Xu J, Chen Q, Liu P, Jia W, Chen Z, Xu Z. Integration of mRNA and miRNA Analysis Reveals the Molecular Mechanism Underlying Salt and Alkali Stress Tolerance in Tobacco. Int J Mol Sci 2019; 20:E2391. [PMID: 31091777 PMCID: PMC6566703 DOI: 10.3390/ijms20102391] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 12/24/2022] Open
Abstract
Salinity is one of the most severe forms of abiotic stress and affects crop yields worldwide. Plants respond to salinity stress via a sophisticated mechanism at the physiological, transcriptional and metabolic levels. However, the molecular regulatory networks involved in salt and alkali tolerance have not yet been elucidated. We developed an RNA-seq technique to perform mRNA and small RNA (sRNA) sequencing of plants under salt (NaCl) and alkali (NaHCO3) stress in tobacco. Overall, 8064 differentially expressed genes (DEGs) and 33 differentially expressed microRNAs (DE miRNAs) were identified in response to salt and alkali stress. A total of 1578 overlapping DEGs, which exhibit the same expression patterns and are involved in ion channel, aquaporin (AQP) and antioxidant activities, were identified. Furthermore, genes involved in several biological processes, such as "photosynthesis" and "starch and sucrose metabolism," were specifically enriched under NaHCO3 treatment. We also identified 15 and 22 miRNAs that were differentially expressed in response to NaCl and NaHCO3, respectively. Analysis of inverse correlations between miRNAs and target mRNAs revealed 26 mRNA-miRNA interactions under NaCl treatment and 139 mRNA-miRNA interactions under NaHCO3 treatment. This study provides new insights into the molecular mechanisms underlying the response of tobacco to salinity stress.
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Affiliation(s)
- Jiayang Xu
- National Tobacco Cultivation and Physiology and Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, China.
| | - Qiansi Chen
- Zhengzhou Tobacco Research Institute, Zhengzhou 450001, China.
| | - Pingping Liu
- Zhengzhou Tobacco Research Institute, Zhengzhou 450001, China.
| | - Wei Jia
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
| | - Zheng Chen
- National Tobacco Cultivation and Physiology and Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, China.
| | - Zicheng Xu
- National Tobacco Cultivation and Physiology and Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, China.
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Stein O, Granot D. An Overview of Sucrose Synthases in Plants. FRONTIERS IN PLANT SCIENCE 2019; 10:95. [PMID: 30800137 PMCID: PMC6375876 DOI: 10.3389/fpls.2019.00095] [Citation(s) in RCA: 236] [Impact Index Per Article: 47.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/21/2019] [Indexed: 05/04/2023]
Abstract
Sucrose is the end product of photosynthesis and the primary sugar transported in the phloem of most plants. Sucrose synthase (SuSy) is a glycosyl transferase enzyme that plays a key role in sugar metabolism, primarily in sink tissues. SuSy catalyzes the reversible cleavage of sucrose into fructose and either uridine diphosphate glucose (UDP-G) or adenosine diphosphate glucose (ADP-G). The products of sucrose cleavage by SuSy are available for many metabolic pathways, such as energy production, primary-metabolite production, and the synthesis of complex carbohydrates. SuSy proteins are usually homotetramers with an average monomeric molecular weight of about 90 kD (about 800 amino acids long). Plant SuSy isozymes are mainly located in the cytosol or adjacent to plasma membrane, but some SuSy proteins are found in the cell wall, vacuoles, and mitochondria. Plant SUS gene families are usually small, containing between four to seven genes, with distinct exon-intron structures. Plant SUS genes are divided into three separate clades, which are present in both monocots and dicots. A comprehensive phylogenetic analysis indicates that a first SUS duplication event may have occurred before the divergence of the gymnosperms and angiosperms and a second duplication event probably occurred in a common angiosperm ancestor, leading to the existence of all three clades in both monocots and dicots. Plants with reduced SuSy activity have been shown to have reduced growth, reduced starch, cellulose or callose synthesis, reduced tolerance to anaerobic-stress conditions and altered shoot apical meristem function and leaf morphology. Plants overexpressing SUS have shown increased growth, increased xylem area and xylem cell-wall width, and increased cellulose and starch contents, making SUS high-potential candidate genes for the improvement of agricultural traits in crop plants. This review summarizes the current knowledge regarding plant SuSy, including newly discovered possible developmental roles for SuSy in meristem functioning that involve sugar and hormonal signaling.
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Affiliation(s)
| | - David Granot
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
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Zhou M, Callaham JB, Reyes M, Stasiak M, Riva A, Zupanska AK, Dixon MA, Paul AL, Ferl RJ. Dissecting Low Atmospheric Pressure Stress: Transcriptome Responses to the Components of Hypobaria in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2017; 8:528. [PMID: 28443120 PMCID: PMC5385376 DOI: 10.3389/fpls.2017.00528] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 03/24/2017] [Indexed: 05/10/2023]
Abstract
Controlled hypobaria presents biology with an environment that is never encountered in terrestrial ecology, yet the apparent components of hypobaria are stresses typical of terrestrial ecosystems. High altitude, for example, presents terrestrial hypobaria always with hypoxia as a component stress, since the relative partial pressure of O2 is constant in the atmosphere. Laboratory-controlled hypobaria, however, allows the dissection of pressure effects away from the effects typically associated with altitude, in particular hypoxia, as the partial pressure of O2 can be varied. In this study, whole transcriptomes of plants grown in ambient (97 kPa/pO2 = 21 kPa) atmospheric conditions were compared to those of plants transferred to five different atmospheres of varying pressure and oxygen composition for 24 h: 50 kPa/pO2 = 10 kPa, 25 kPa/pO2 = 5 kPa, 50 kPa/pO2 = 21 kPa, 25 kPa/pO2 = 21 kPa, or 97 kPa/pO2 = 5 kPa. The plants exposed to these environments were 10 day old Arabidopsis seedlings grown vertically on hydrated nutrient plates. In addition, 5 day old plants were also exposed for 24 h to the 50 kPa and ambient environments to evaluate age-dependent responses. The gene expression profiles from roots and shoots showed that the hypobaric response contained more complex gene regulation than simple hypoxia, and that adding back oxygen to normoxic conditions did not completely alleviate gene expression changes in hypobaric responses.
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Affiliation(s)
- Mingqi Zhou
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of FloridaGainesville, FL, USA
| | - Jordan B. Callaham
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of FloridaGainesville, FL, USA
| | | | - Michael Stasiak
- School of Environmental Sciences, University of GuelphGuelph, ON, Canada
| | - Alberto Riva
- Interdisciplinary Center for Biotechnology Research, University of FloridaGainesville, FL, USA
| | - Agata K. Zupanska
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of FloridaGainesville, FL, USA
| | - Mike A. Dixon
- School of Environmental Sciences, University of GuelphGuelph, ON, Canada
| | - Anna-Lisa Paul
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of FloridaGainesville, FL, USA
- *Correspondence: Anna-Lisa Paul
| | - Robert J. Ferl
- Department of Horticultural Sciences, Program in Plant Molecular and Cellular Biology, University of FloridaGainesville, FL, USA
- Interdisciplinary Center for Biotechnology Research, University of FloridaGainesville, FL, USA
- Robert J. Ferl
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Cieśla A, Mituła F, Misztal L, Fedorowicz-Strońska O, Janicka S, Tajdel-Zielińska M, Marczak M, Janicki M, Ludwików A, Sadowski J. A Role for Barley Calcium-Dependent Protein Kinase CPK2a in the Response to Drought. FRONTIERS IN PLANT SCIENCE 2016; 7:1550. [PMID: 27826303 PMCID: PMC5078816 DOI: 10.3389/fpls.2016.01550] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/03/2016] [Indexed: 05/30/2023]
Abstract
Increasing the drought tolerance of crops is one of the most challenging goals in plant breeding. To improve crop productivity during periods of water deficit, it is essential to understand the complex regulatory pathways that adapt plant metabolism to environmental conditions. Among various plant hormones and second messengers, calcium ions are known to be involved in drought stress perception and signaling. Plants have developed specific calcium-dependent protein kinases that convert calcium signals into phosphorylation events. In this study we attempted to elucidate the role of a calcium-dependent protein kinase in the drought stress response of barley (Hordeum vulgare L.), one of the most economically important crops worldwide. The ongoing barley genome project has provided useful information about genes potentially involved in the drought stress response, but information on the role of calcium-dependent kinases is still limited. We found that the gene encoding the calcium-dependent protein kinase HvCPK2a was significantly upregulated in response to drought. To better understand the role of HvCPK2a in drought stress signaling, we generated transgenic Arabidopsis plants that overexpressed the corresponding coding sequence. Overexpressing lines displayed drought sensitivity, reduced nitrogen balance index (NBI), an increase in total chlorophyll content and decreased relative water content. In addition, in vitro kinase assay experiments combined with mass spectrometry allowed HvCPK2a autophosphorylation sites to be identified. Our results suggest that HvCPK2a is a dual-specificity calcium-dependent protein kinase that functions as a negative regulator of the drought stress response in barley.
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Affiliation(s)
- Agata Cieśla
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | - Filip Mituła
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | - Lucyna Misztal
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | | | - Sabina Janicka
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | | | - Małgorzata Marczak
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | - Maciej Janicki
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | - Agnieszka Ludwików
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
| | - Jan Sadowski
- Biotechnology Department, Faculty of Biology, Adam Mickiewicz UniversityPoznań, Poland
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7
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Overexpression of Arabidopsis AnnAt8 Alleviates Abiotic Stress in Transgenic Arabidopsis and Tobacco. PLANTS 2016; 5:plants5020018. [PMID: 27135239 PMCID: PMC4931398 DOI: 10.3390/plants5020018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 03/28/2016] [Accepted: 04/01/2016] [Indexed: 01/11/2023]
Abstract
Abiotic stress results in massive loss of crop productivity throughout the world. Because of our limited knowledge of the plant defense mechanisms, it is very difficult to exploit the plant genetic resources for manipulation of traits that could benefit multiple stress tolerance in plants. To achieve this, we need a deeper understanding of the plant gene regulatory mechanisms involved in stress responses. Understanding the roles of different members of plant gene families involved in different stress responses, would be a step in this direction. Arabidopsis, which served as a model system for the plant research, is also the most suitable system for the functional characterization of plant gene families. Annexin family in Arabidopsis also is one gene family which has not been fully explored. Eight annexin genes have been reported in the genome of Arabidopsis thaliana. Expression studies of different Arabidopsis annexins revealed their differential regulation under various abiotic stress conditions. AnnAt8 (At5g12380), a member of this family has been shown to exhibit ~433 and ~175 fold increase in transcript levels under NaCl and dehydration stress respectively. To characterize Annexin8 (AnnAt8) further, we have generated transgenic Arabidopsis and tobacco plants constitutively expressing AnnAt8, which were evaluated under different abiotic stress conditions. AnnAt8 overexpressing transgenic plants exhibited higher seed germination rates, better plant growth, and higher chlorophyll retention when compared to wild type plants under abiotic stress treatments. Under stress conditions transgenic plants showed comparatively higher levels of proline and lower levels of malondialdehyde compared to the wild-type plants. Real-Time PCR analyses revealed that the expression of several stress-regulated genes was altered in AnnAt8 over-expressing transgenic tobacco plants, and the enhanced tolerance exhibited by the transgenic plants can be correlated with altered expressions of these stress-regulated genes. Our findings suggest a role for AnnAt8 in enhancing abiotic stress tolerance at different stages of plant growth and development.
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8
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Jiang SC, Mei C, Liang S, Yu YT, Lu K, Wu Z, Wang XF, Zhang DP. Crucial roles of the pentatricopeptide repeat protein SOAR1 in Arabidopsis response to drought, salt and cold stresses. PLANT MOLECULAR BIOLOGY 2015; 88:369-85. [PMID: 26093896 PMCID: PMC4486114 DOI: 10.1007/s11103-015-0327-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 04/29/2015] [Indexed: 05/07/2023]
Abstract
Whereas several mitochondrial/chloroplast pentatricopeptide repeat (PPR) proteins have been reported to regulate plant responses to abiotic stresses, no nucleus-localized PPR protein has been found to play role in these processes. In the present experiment, we provide evidence that a cytosol-nucleus dual-localized PPR protein SOAR1, functioning to negatively regulate abscisic acid (ABA) signaling in seed germination and postgermination growth, is a crucial, positive regulator of plant response to abiotic stresses. Downregulation of SOAR1 expression reduces, but upregulation of SOAR1 expression enhances, ABA sensitivity in ABA-induced promotion of stomatal closure and inhibition of stomatal opening, and plant tolerance to multiple, major abiotic stresses including drought, high salinity and low temperature. Interestingly and importantly, the SOAR1-overexpression lines display strong abilities to tolerate drought, salt and cold stresses, with surprisingly high resistance to salt stress in germination and postgermination growth of seeds that are able to potentially germinate in seawater, while no negative effect on plant growth and development was observed. So, the SOAR1 gene is likely useful for improvement of crops by transgenic manipulation to enhance crop productivity in stressful conditions. Further experimental data suggest that SOAR1 likely regulates plant stress responses at least partly by integrating ABA-dependent and independent signaling pathways, which is different from the ABI2/ABI1 type 2C protein phosphatase-mediated ABA signaling. These findings help to understand highly complicated stress and ABA signalling network.
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Affiliation(s)
- Shang-Chuan Jiang
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Chao Mei
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Shan Liang
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Yong-Tao Yu
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Kai Lu
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Zhen Wu
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Xiao-Fang Wang
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - Da-Peng Zhang
- MOE Systems Biology and Bioinformatics Laboratory, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084 China
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Papdi C, Pérez-Salamó I, Joseph MP, Giuntoli B, Bögre L, Koncz C, Szabados L. The low oxygen, oxidative and osmotic stress responses synergistically act through the ethylene response factor VII genes RAP2.12, RAP2.2 and RAP2.3. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:772-84. [PMID: 25847219 DOI: 10.1111/tpj.12848] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 05/22/2023]
Abstract
The ethylene response factor VII (ERF-VII) transcription factor RELATED TO APETALA2.12 (RAP2.12) was previously identified as an activator of the ALCOHOL DEHYDROGENASE1 promoter::luciferase (ADH1-LUC) reporter gene. Here we show that overexpression of RAP2.12 and its homologues RAP2.2 and RAP2.3 sustains ABA-mediated activation of ADH1 and activates hypoxia marker genes under both anoxic and normoxic conditions. Inducible expression of all three RAP2s conferred tolerance to anoxia, oxidative and osmotic stresses, and enhanced the sensitivity to abscisic acid (ABA). Consistently, the rap2.12-2 rap2.3-1 double mutant showed hypersensitivity to both submergence and osmotic stress. These findings suggest that the three ERF-VII-type transcription factors play roles in tolerance to multiple stresses that sequentially occur during and after submergence in Arabidopsis. Oxygen-dependent degradation of RAP2.12 was previously shown to be mediated by the N-end rule pathway. During submergence the RAP2.12, RAP2.2 and RAP2.3 are stabilized and accumulates in the nucleus affecting the transcription of stress response genes. We conclude that the stabilized RAP2 transcription factors can prolong the ABA-mediated activation of a subset of osmotic responsive genes (e.g. ADH1). We also show that RAP2.12 protein level is affected by the REALLY INTERESTING GENE (RING) domain containing SEVEN IN ABSENTIA of Arabidopsis thaliana 2 (SINAT2). Silencing of SINAT1/2 genes leads to enhanced RAP2.12 abundance independently of the presence or absence of its N-terminal degron. Taken together, our results suggest that RAP2.12 and its homologues RAP2.2 and RAP2.3 act redundantly in multiple stress responses. Alternative protein degradation pathways may provide inputs to the RAP2 transcription factors for the distinct stresses.
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Affiliation(s)
- Csaba Papdi
- Biological Research Centre, Institute of Plant Biology, Temesvári krt. 62., H-6726, Szeged, Hungary
- Royal Holloway, University of London, Egham Hill, Surrey, TW20 0EX, UK
| | - Imma Pérez-Salamó
- Biological Research Centre, Institute of Plant Biology, Temesvári krt. 62., H-6726, Szeged, Hungary
- Royal Holloway, University of London, Egham Hill, Surrey, TW20 0EX, UK
| | - Mary Prathiba Joseph
- Biological Research Centre, Institute of Plant Biology, Temesvári krt. 62., H-6726, Szeged, Hungary
| | - Beatrice Giuntoli
- Institute of Life Sciences, Scuola Superiore Sant'Anna, 56127, Pisa, Italy
| | - László Bögre
- Royal Holloway, University of London, Egham Hill, Surrey, TW20 0EX, UK
| | - Csaba Koncz
- Biological Research Centre, Institute of Plant Biology, Temesvári krt. 62., H-6726, Szeged, Hungary
- Max-Planck-Institut für Züchtungsforschung, Carl von Linne weg 10., 50829, Cologne, Germany
| | - László Szabados
- Biological Research Centre, Institute of Plant Biology, Temesvári krt. 62., H-6726, Szeged, Hungary
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10
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Chandra A, Verma PK, Islam MN, Grisham MP, Jain R, Sharma A, Roopendra K, Singh K, Singh P, Verma I, Solomon S. Expression analysis of genes associated with sucrose accumulation in sugarcane (Saccharum spp. hybrids) varieties differing in content and time of peak sucrose storage. PLANT BIOLOGY (STUTTGART, GERMANY) 2015; 17:608-17. [PMID: 25311688 DOI: 10.1111/plb.12276] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 10/03/2014] [Indexed: 05/27/2023]
Abstract
Sucrose synthesis/accumulation in sugarcane is a complex process involving many genes and regulatory sequences that control biochemical events in source-sink tissues. Among these, sucrose synthase (SuSy), sucrose phosphate synthase (SPS), soluble acid (SAI) and cell wall (CWI) invertases are important. Expression of these enzymes was compared in an early (CoJ64) and late (BO91) maturing sugarcane variety using end-point and qRT-PCR. Quantitative RT-PCR at four crop stages revealed high CWI expression in upper internodes of CoJ64, which declined significantly in both top and bottom internodes with maturity. In BO91, CWI expression was high in top and bottom internodes and declined significantly only in top internodes as the crop matured. Overall, CWI expression was higher in CoJ64 than in BO91. During crop growth, there was no significant change in SPS expression in bottom internodes in CoJ64, whereas in BO91 it decreased significantly. Apart from a significant decrease in expression of SuSy in mature bottom internodes of BO91, there was no significant change. Similar SAI expression was observed with both end-point and RT-PCR, except for significantly increased expression in top internodes of CoJ64 with maturity. SAI, being a major sucrose hydrolysing enzyme, was also monitored with end-point PCR expression in internode tissues of CoJ64 and BO91, with higher expression of SAI in BO91 at early crop stages. Enzyme inhibitors, e.g. manganese chloride (Mn(++) ), significantly suppressed expression of SAI in both early- and late-maturing varieties. Present findings enhance understanding of critical sucrose metabolic gene expression in sugarcane varieties differing in content and time of peak sucrose storage. Thus, through employing these genes, improvement of sugarcane sucrose content is possible.
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Affiliation(s)
- A Chandra
- Division of Plant Physiology and Biochemistry, Indian Institute of Sugarcane Research, Lucknow, India
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11
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Wang H, Sui X, Guo J, Wang Z, Cheng J, Ma S, Li X, Zhang Z. Antisense suppression of cucumber (Cucumis sativus L.) sucrose synthase 3 (CsSUS3) reduces hypoxic stress tolerance. PLANT, CELL & ENVIRONMENT 2014; 37:795-810. [PMID: 24028217 DOI: 10.1111/pce.12200] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Sucrose synthase (SUS; EC 2.4.1.13) plays important roles in sugar metabolism and abiotic stress response. But the genes encoding SUS in cucumber (Cucumis sativus L.) have not been well studied. Here, we isolated four cucumber sucrose synthase genes (CsSUS). Among them, CsSUS3, which highly expressed in the roots, was chosen for further study. Immunolocalization and subcellular localization analysis indicated that CsSUS3 localized in the cytosol and the plasma membrane, and mainly existed in the companion cells of phloem in the roots. When suffering hypoxia stress from flooding, CsSUS3 expression and SUS activity in roots increased, especially in the lateral roots; moreover, the soluble SUS activity increased clearly, but the membrane fraction hardly changed. Compared with the wild-type cucumbers, the transgenic lines with antisense expression of CsSUS3 were more sensitive to flooding. After 6 d of flooding, the SUS activity, soluble sugar and uridine 5'-diphosphate glucose (UDPG) content and the ratio of ATP/ADP in the roots of transgenic plants were significantly lower than that in wild-type plants. Moreover, the transgenic lines grew more slowly with more yellow necrosis in the leaves. These findings suggested CsSUS3 participated in resisting hypoxic stress. Furthermore, the mechanism of CsSUS3 in resisting hypoxic stress was also discussed.
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Affiliation(s)
- Hongyun Wang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agriculture University, Beijing, 100193, China; Yantai Agricultural Science and Technology Institute, Yantai, 265500, China
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12
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Deng X, Zhou S, Hu W, Feng J, Zhang F, Chen L, Huang C, Luo Q, He Y, Yang G, He G. Ectopic expression of wheat TaCIPK14, encoding a calcineurin B-like protein-interacting protein kinase, confers salinity and cold tolerance in tobacco. PHYSIOLOGIA PLANTARUM 2013; 149:367-77. [PMID: 23534344 DOI: 10.1111/ppl.12046] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 02/22/2013] [Accepted: 02/22/2013] [Indexed: 05/08/2023]
Abstract
Calcineurin B-like protein-interacting protein kinases (CIPKs) are components of Ca(2+) signaling in responses to abiotic stresses. In this work, the full-length cDNA of a novel CIPK gene (TaCIPK14) was isolated from wheat and was found to have significant sequence similarity to OsCIPK14/15. Subcellular localization assay revealed the presence of TaCIPK14 throughout the cell. qRT-PCR analysis showed that TaCIPK14 was upregulated under cold conditions or when treated with salt, PEG or exogenous stresses related signaling molecules including ABA, ethylene and H2 O2 . Transgenic tobaccos overexpressing TaCIPK14 exhibited higher contents of chlorophyll and sugar, higher catalase activity, while decreased amounts of H2 O2 and malondialdehyde, and lesser ion leakage under cold and salt stresses. In addition, overexpression also increased seed germination rate, root elongation and decreased Na(+) content in the transgenic lines under salt stress. Higher expression of stress-related genes was observed in lines overexpressing TaCIPK14 compared to controls under stress conditions. In summary, these results suggested that TaCIPK14 is an abiotic stress-responsive gene in plants.
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Affiliation(s)
- Xiaomin Deng
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of life Science and Technology, Huazhong University of Science & Technology (HUST), Wuhan, 430074, China
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13
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Bahaji A, Li J, Sánchez-López ÁM, Baroja-Fernández E, Muñoz FJ, Ovecka M, Almagro G, Montero M, Ezquer I, Etxeberria E, Pozueta-Romero J. Starch biosynthesis, its regulation and biotechnological approaches to improve crop yields. Biotechnol Adv 2013; 32:87-106. [PMID: 23827783 DOI: 10.1016/j.biotechadv.2013.06.006] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 06/21/2013] [Indexed: 01/08/2023]
Abstract
Structurally composed of the glucose homopolymers amylose and amylopectin, starch is the main storage carbohydrate in vascular plants, and is synthesized in the plastids of both photosynthetic and non-photosynthetic cells. Its abundance as a naturally occurring organic compound is surpassed only by cellulose, and represents both a cornerstone for human and animal nutrition and a feedstock for many non-food industrial applications including production of adhesives, biodegradable materials, and first-generation bioethanol. This review provides an update on the different proposed pathways of starch biosynthesis occurring in both autotrophic and heterotrophic organs, and provides emerging information about the networks regulating them and their interactions with the environment. Special emphasis is given to recent findings showing that volatile compounds emitted by microorganisms promote both growth and the accumulation of exceptionally high levels of starch in mono- and dicotyledonous plants. We also review how plant biotechnologists have attempted to use basic knowledge on starch metabolism for the rational design of genetic engineering traits aimed at increasing starch in annual crop species. Finally we present some potential biotechnological strategies for enhancing starch content.
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Affiliation(s)
- Abdellatif Bahaji
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Jun Li
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Ángela María Sánchez-López
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Edurne Baroja-Fernández
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Francisco José Muñoz
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Miroslav Ovecka
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain; Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Cell Biology, Faculty of Science, Palacky University, Šlechtitelů 11, CZ-783 71 Olomouc, Czech Republic
| | - Goizeder Almagro
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Manuel Montero
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Ignacio Ezquer
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain
| | - Ed Etxeberria
- University of Florida, Institute of Food and Agricultural Sciences, Citrus Research and Education Center, 700 Experiment Station Road, Lake Alfred, FL 33850-2299, USA
| | - Javier Pozueta-Romero
- Instituto de Agrobiotecnología (CSIC/UPNA/Gobierno de Navarra), Mutiloako etorbidea z/g, 31192 Mutiloabeti, Nafarroa, Spain.
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14
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Almagro G, Baroja-Fernández E, Muñoz FJ, Bahaji A, Etxeberria E, Li J, Montero M, Hidalgo M, Sesma MT, Pozueta-Romero J. No evidence for the occurrence of substrate inhibition of Arabidopsis thaliana sucrose synthase-1 (AtSUS1) by fructose and UDP-glucose. PLANT SIGNALING & BEHAVIOR 2012; 7:799-802. [PMID: 22751299 PMCID: PMC3583967 DOI: 10.4161/psb.20601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Sucrose synthase (SuSy) catalyzes the reversible conversion of sucrose and NDP into the corresponding nucleotide-sugars and fructose. The Arabidopsis genome possesses six SUS genes (AtSUS1-6) that code for proteins with SuSy activity. As a first step to investigate optimum fructose and UDP-glucose (UDPG) concentrations necessary to measure maximum sucrose-producing SuSy activity in crude extracts of Arabidopsis, in this work we performed kinetic analyses of recombinant AtSUS1 in two steps: (1) SuSy reaction at pH 7.5, and (2) chromatographic measurement of sucrose produced in step 1. These analyses revealed a typical Michaelis-Menten behavior with respect to both UDPG and fructose, with Km values of 50 μM and 25 mM, respectively. Unlike earlier studies showing the occurrence of substrate inhibition of UDP-producing AtSUS1 by fructose and UDP-glucose, these analyses also revealed no substrate inhibition of AtSUS1 at any UDPG and fructose concentration. By including 200 mM fructose and 1 mM UDPG in the SuSy reaction assay mixture, we found that sucrose-producing SuSy activity in leaves and stems of Arabidopsis were exceedingly higher than previously reported activities. Furthermore, we found that SuSy activities in organs of the sus1/sus2/sus3/sus4 mutant were ca. 80-90% of those found in WT plants.
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Affiliation(s)
- Goizeder Almagro
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Edurne Baroja-Fernández
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Francisco José Muñoz
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Abdellatif Bahaji
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Ed Etxeberria
- IFAS; Citrus Research and Education Center; University of Florida; Lake Alfred, FL USA
| | - Jun Li
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Manuel Montero
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Maite Hidalgo
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - María Teresa Sesma
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
| | - Javier Pozueta-Romero
- Instituto de Agrobiotecnología; Universidad Pública de Navarra; Consejo Superior de Investigaciones Científicas; Gobierno de Navarra; Mutiloako Etorbidea Zenbaki Gabe; Nafarroa, Spain
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15
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Angeles-Núñez JG, Tiessen A. Regulation of AtSUS2 and AtSUS3 by glucose and the transcription factor LEC2 in different tissues and at different stages of Arabidopsis seed development. PLANT MOLECULAR BIOLOGY 2012; 78:377-92. [PMID: 22228409 DOI: 10.1007/s11103-011-9871-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 12/14/2011] [Indexed: 05/25/2023]
Abstract
Sucrose synthase (SUS) is a key enzyme of carbon metabolism in heterotrophic tissues of plants. The Arabidopsis genome contains six SUS genes. Two members of this family, namely AtSUS2 (At5g49190) and AtSUS3 (At4g02280) are strongly and differentially expressed in Arabidopsis seed. Expression analysis was carried out using SUS:promoter-GUS fusion lines in a wild-type genetic background or in a mutant carrying a lesion in the transcription factor LEAFY COTYLEDON 2 (LEC2; At1g28300). The accumulation patterns of mRNA, protein, and SUS activity were altered in the lec2 mutant during seed development 9-18 days after flowering. This indicates that LEC2 acts epistatically on the expression of AtSUS2 and AtSUS3. It appears that LEC2 is required for cotyledon-specific expression of both SUS genes but it is not responsible for expression in the radicle tip during embryo development. The AtSUS2 promoter was induced in planta by feeding of glucose but less so by sucrose and trehalose. Non-phosphorylable glucose analogs such as 3-O-methyl-glucose and 2-deoxyglucose also caused an induction, suggesting that sugar signaling proceeds by a hexokinase-independent pathway, possibly involving hexose sensing. Analysis of transgenic lines carrying of truncated versions of the AtSUS2:promoter fused to Beta-glucuronidase activity revealed an internal 421 bp region that was responsible for expression in seeds. Bioinformatic sequence analysis revealed regulatory cis-elements putatively responsible for the spatio-temporal pattern of AtSUS2 expression such as the SEF3 (aaccca) and W-box (ttgact) motifs. These findings are discussed in relation to the roles played by AtSUS2, AtSUS3 and LEC2 in the biosynthesis of seed storage products in Arabidopsis.
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Affiliation(s)
- Juan Gabriel Angeles-Núñez
- Departamento de Ingeniería Genética, CINVESTAV, Unidad Irapuato, Km 9.8 Libramiento Norte, CP 36821 Irapuato, Guanajuato, Mexico
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16
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Veley KM, Marshburn S, Clure CE, Haswell ES. Mechanosensitive channels protect plastids from hypoosmotic stress during normal plant growth. Curr Biol 2012; 22:408-13. [PMID: 22326022 DOI: 10.1016/j.cub.2012.01.027] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 01/02/2012] [Accepted: 01/12/2012] [Indexed: 10/14/2022]
Abstract
Cellular response to osmotic stress is critical for survival and involves volume control through the regulated transport of osmolytes. Organelles may respond similarly to abrupt changes in cytoplasmic osmolarity. The plastids of the Arabidopsis thaliana leaf epidermis provide a model system for the study of organellar response to osmotic stress within the context of the cell. An Arabidopsis mutant lacking two plastid-localized homologs of the bacteria mechanosensitive channel MscS (MscS-like [MSL] 2 and 3) exhibits large round epidermal plastids that lack dynamic extensions known as stromules. This phenotype is present under normal growth conditions and does not require exposure to extracellular osmotic stress. Here we show that increasing cytoplasmic osmolarity through a genetic lesion known to produce elevated levels of soluble sugars, exogenously providing osmolytes in the growth media, or withholding water rescues the msl2-1 msl3-1 leaf epidermal plastid phenotype, producing plastids that resemble the wild-type in shape and size. Furthermore, the epidermal plastids in msl2-1 msl3-1 leaves undergo rapid and reversible volume and shape changes in response to extracellular hypertonic or hypotonic challenges. We conclude that plastids are under hypoosmotic stress during normal plant growth and dynamic response to this stress requires MSL2 and MSL3.
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Affiliation(s)
- Kira M Veley
- Department of Biology, Washington University in St. Louis, Campus Box 1137, St. Louis, MO 63130, USA
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17
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Chang JC, Liao YC, Yang CC, Wang AY. The purine-rich DNA-binding protein OsPurα participates in the regulation of the rice sucrose synthase 1 gene expression. PHYSIOLOGIA PLANTARUM 2011; 143:219-234. [PMID: 21834856 DOI: 10.1111/j.1399-3054.2011.01501.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The rice sucrose synthase 1 (RSus1) gene is transcriptionally induced by sucrose, and a region within its promoter, at -1117 to -958 upstream of the transcription initiation site, was found to be essential for enhancing the sucrose-induced expression. Further dissection of this region revealed that a group of nuclear proteins interact with a 39-bp fragment named A-3-2 (-1045 to -1007). A protein that specifically and directly interacted with A-3-2 was isolated from the suspension-cultured cells of rice and was subsequently identified as a purine-rich DNA-binding protein. The amino acid sequence of this protein, OsPurα, exhibited 73% identity with the Arabidopsis Purα-1 protein, and its modeled structure resembled the structure of Pur-α in Drosophila. Recombinant OsPurα expressed and purified from Escherichia coli was demonstrated to have DNA-binding activity and to interact with A-3-2 specifically. Moreover, OsPurα was able to enhance sucrose-induced expression of the β-glucuronidase (GUS) reporter gene, which was transcriptionally fused to two copies of a DNA fragment containing A-3-2 and the cauliflower mosaic virus 35S minimal promoter, in vivo. The level of OsPurα bound to A-3-2 was higher in cells cultured in the presence of sucrose; however, the level of OsPurα mRNA in cells was not affected by sucrose. The results of this study demonstrate that OsPurα participates in the regulation of RSus1 expression in response to sucrose; nevertheless, it may require other partner proteins for full function.
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Affiliation(s)
- Jui-Che Chang
- Department of Biochemical Science and Technology, National Taiwan University, Taipei, Taiwan
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18
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Poplar under drought: comparison of leaf and cambial proteomic responses. J Proteomics 2011; 74:1396-410. [PMID: 21439416 DOI: 10.1016/j.jprot.2011.03.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 02/25/2011] [Accepted: 03/14/2011] [Indexed: 10/18/2022]
Abstract
The forest ecosystem is of particular importance from an economic and ecological perspective. However, the stress physiology of trees, perennial and woody plants, is far from being fully understood. For that purpose, poplar plants were exposed to drought; the plants exhibited commonly reported drought stress traits in the different plant tissues. Leafy rooted cuttings of poplar were investigated through a proteomic approach in order to compare the water constraint response of two plant tissues, namely leaf and cambium. Sampling was realized during the drought period at 2 time points with increased drought intensity and 7 days after rewatering. Our data show that there is a difference in the moment of response to the water constraint between the two tissues, cambium being affected later than leaves. In leaves, drought induced a decrease in rubisco content, and an increase in the abundance of light harvesting complex proteins as well as changes in membrane-related proteins. In the cambial tissue, the salient proteome pattern change was the decrease of multiple proteins identified as bark storage proteins. After rewatering, almost all changes in cambial proteome disappeared whereas a significant number of leaf proteins appeared to be differentially regulated only during the recovery from drought.
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19
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Verma AK, Upadhyay SK, Verma PC, Solomon S, Singh SB. Functional analysis of sucrose phosphate synthase (SPS) and sucrose synthase (SS) in sugarcane (Saccharum) cultivars. PLANT BIOLOGY (STUTTGART, GERMANY) 2011; 13:325-32. [PMID: 21309979 DOI: 10.1111/j.1438-8677.2010.00379.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Sucrose phosphate synthase (SPS; EC 2.4.1.14) and sucrose synthase (SS; EC 2.4.1.13) are key enzymes in the synthesis and breakdown of sucrose in sugarcane. The activities of internodal SPS and SS, as well as transcript expression were determined using semi-quantitative RT-PCR at different developmental stages of high and low sucrose accumulating sugarcane cultivars. SPS activity and transcript expression was higher in mature internodes compared with immature internodes in all the studied cultivars. However, high sugar cultivars showed increased transcript expression and enzyme activity of SPS compared to low sugar cultivars at all developmental stages. SS activity was higher in immature internodes than in mature internodes in all cultivars; SS transcript expression showed a similar pattern. Our studies demonstrate that SPS activity was positively correlated with sucrose and negatively correlated with hexose sugars. However, SS activity was negatively correlated with sucrose and positively correlated with hexose sugars. The present study opens the possibility for improvement of sugarcane cultivars by increasing expression of the respective enzymes using transgene technology.
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Affiliation(s)
- A K Verma
- U.P. Council of Sugarcane Research, Shahjahanpur, India.
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20
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Boris KV, Ryzhova NN, Kochieva EZ. Identification and characterization of intraspecific variability of the sucrose synthase gene Sus4 of potato (Solanum tuberosum). RUSS J GENET+ 2011. [DOI: 10.1134/s1022795411020074] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Ray S, Dansana PK, Giri J, Deveshwar P, Arora R, Agarwal P, Khurana JP, Kapoor S, Tyagi AK. Modulation of transcription factor and metabolic pathway genes in response to water-deficit stress in rice. Funct Integr Genomics 2010; 11:157-78. [PMID: 20821243 DOI: 10.1007/s10142-010-0187-y] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2010] [Revised: 08/10/2010] [Accepted: 08/16/2010] [Indexed: 01/04/2023]
Abstract
Water-deficit stress is detrimental for rice growth, development, and yield. Transcriptome analysis of 1-week-old rice (Oryza sativa L. var. IR64) seedling under water-deficit stress condition using Affymetrix 57 K GeneChip® has revealed 1,563 and 1,746 genes to be up- and downregulated, respectively. In an effort to amalgamate data across laboratories, we identified 5,611 differentially expressing genes under varying extrinsic water-deficit stress conditions in six vegetative and one reproductive stage of development in rice. Transcription factors (TFs) involved in ABA-dependent and ABA-independent pathways have been found to be upregulated during water-deficit stress. Members of zinc-finger TFs namely, C₂H₂, C₂C₂, C₃H, LIM, PHD, WRKY, ZF-HD, and ZIM, along with TF families like GeBP, jumonji, MBF1 and ULT express differentially under water-deficit conditions. NAC (NAM, ATAF and CUC) TF family emerges to be a potential key regulator of multiple abiotic stresses. Among the 12 TF genes that are co-upregulated under water-deficit, salt and cold stress conditions, five belong to the NAC TF family. We identified water-deficit stress-responsive genes encoding key enzymes involved in biosynthesis of osmoprotectants like polyols and sugars; amino acid and quaternary ammonium compounds; cell wall loosening and structural components; cholesterol and very long chain fatty acid; cytokinin and secondary metabolites. Comparison of genes responsive to water-deficit stress conditions with genes preferentially expressed during panicle and seed development revealed a significant overlap of transcriptome alteration and pathways.
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Affiliation(s)
- Swatismita Ray
- Interdisciplinary Centre for Plant Genomics and Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India
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22
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Influence of environmental factors, wet processing and their interactions on the biochemical composition of green Arabica coffee beans. Food Chem 2010. [DOI: 10.1016/j.foodchem.2009.05.048] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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23
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Meng M, Fitzek E, Gajowniczek A, Wilczynska M, Kleczkowski LA. Domain-specific determinants of catalysis/substrate binding and the oligomerization status of barley UDP-glucose pyrophosphorylase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1794:1734-42. [PMID: 19683599 DOI: 10.1016/j.bbapap.2009.08.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2009] [Revised: 08/01/2009] [Accepted: 08/05/2009] [Indexed: 11/26/2022]
Abstract
UDP-glucose (UDPG) pyrophosphorylase (UGPase) produces UDPG for sucrose and polysaccharide synthesis and glycosylation reactions. In this study, several barley UGPase mutants were produced, either single amino acid mutants or involving deletions of N- and C-terminal domains (Ncut and Ccut mutants, respectively) and of active site region ("NB loop"). The Del-NB mutant yielded no activity, whereas Ncut deletions and most of Ccut mutants, including short deletions at the so called "I-loop" region of C-terminal domain, as well as a single K260A mutant resulted in very low activity. For wt and the mutants, kinetics with UDPG were linear on reciprocal plots, whereas PPi at concentrations above 1 mM exerted strong substrate inhibition. Both K260A and most of the Ccut mutants had very high Km with PPi (up to 33 mM), whereas Ncut deletions had greatly increased Km with UDPG (up to 57 mM). Surprisingly, an 8 amino acid deletion from end of the C-terminus resulted in an enzyme (Ccut-8 mutant) with 44% higher activity when compared to wt, but with similar Km values. Whereas Ccut-8 existed solely as a monomer, other deletion mutants had a more oligomerized status, e.g. Ncut mutants existing primarily as dimers. Overall, the data confirmed the essential role of NB loop in catalysis, but also pointed out to the role of both N- and C-termini for activity, substrate binding and oligomerization. The importance of oligomerization status for enzymatic activity of UGPase is discussed.
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Affiliation(s)
- Meng Meng
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, 901 87 Umeå, Sweden
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Meng M, Wilczynska M, Kleczkowski LA. Molecular and kinetic characterization of two UDP-glucose pyrophosphorylases, products of distinct genes, from Arabidopsis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:967-72. [DOI: 10.1016/j.bbapap.2008.02.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 02/26/2008] [Accepted: 02/29/2008] [Indexed: 10/22/2022]
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25
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Marino D, Hohnjec N, Küster H, Moran JF, González EM, Arrese-Igor C. Evidence for transcriptional and post-translational regulation of sucrose synthase in pea nodules by the cellular redox state. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2008; 21:622-30. [PMID: 18393622 DOI: 10.1094/mpmi-21-5-0622] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Nitrogen fixation (NF) in legume nodules is very sensitive to environmental constraints. Nodule sucrose synthase (SS; EC 2.4.1.13) has been suggested to play a crucial role in those circumstances because its downregulation leads to an impaired glycolytic carbon flux and, therefore, a depletion of carbon substrates for bacteroids. In the present study, the likelihood of SS being regulated by oxidative signaling has been addressed by the in vivo supply of paraquat (PQ) to nodulated pea plants and the in vitro effects of oxidizing and reducing agents on nodule SS. PQ produced cellular redox imbalance leading to an inhibition of NF. This was preceded by the downregulation of SS gene expression, protein content, and activity. In vitro, oxidizing agents were able to inhibit SS activity and this inhibition was completely reversed by the addition of dithiothreitol. The overall results are consistent with a regulation model of nodule SS exerted by the cellular redox state at both the transcriptional and post-translational levels. The importance of such mechanisms for the regulation of NF in response to environmental stresses are discussed.
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Affiliation(s)
- Daniel Marino
- Departamento de Ciencias del Medio Natural, Universidad Pública de Navarra, E-31006 Pamplona, Spain
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Geromel C, Ferreira LP, Davrieux F, Guyot B, Ribeyre F, Brígida dos Santos Scholz M, Protasio Pereira LF, Vaast P, Pot D, Leroy T, Androcioli Filho A, Esteves Vieira LG, Mazzafera P, Marraccini P. Effects of shade on the development and sugar metabolism of coffee (Coffea arabica L.) fruits. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2008; 46:569-79. [PMID: 18420417 DOI: 10.1016/j.plaphy.2008.02.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Indexed: 05/11/2023]
Abstract
Coffee fruits grown in shade are characterized by larger bean size than those grown under full-sun conditions. The present study assessed the effects of shade on bean characteristics and sugar metabolism by analyzing tissue development, sugar contents, activities of sucrose metabolizing enzymes and expression of sucrose synthase-encoding genes in fruits of coffee (Coffea arabica L.) plants submitted to full-sun (FS) and shade (SH) conditions. Evolution of tissue fresh weights measured in fruits collected regularly from flowering to maturation indicated that this increase is due to greater development of the perisperm tissue in the shade. The effects of light regime on sucrose and reducing sugar (glucose and fructose) contents were studied in fresh and dry coffee beans. Shade led to a significant reduction in sucrose content and to an increase in reducing sugars. In pericarp and perisperm tissues, higher activities of sucrose synthase (EC 2.4.1.13) and sucrose-phosphate synthase (SPS: EC 2.4.1.14) were detected at maturation in the shade compared with full sun. These two enzymes also had higher peaks of activities in developing endosperm under shade than in full sun. It was also noted that shade modified the expression of SUS-encoding genes in coffee beans; CaSUS2 gene transcripts levels were higher in SH than in FS. As no sucrose increase accompanied these changes, this suggests that sucrose metabolism was redirected to other metabolic pathways that need to be identified.
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Affiliation(s)
- Clara Geromel
- Departamento de Fisiologia Vegetal-IB, UNICAMP, CP 6109, 13083-970 Campinas, SP, Brazil
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Klotz KL, Haagenson DM. Wounding, anoxia and cold induce sugarbeet sucrose synthase transcriptional changes that are unrelated to protein expression and activity. JOURNAL OF PLANT PHYSIOLOGY 2008; 165:423-34. [PMID: 17395334 DOI: 10.1016/j.jplph.2007.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 02/06/2007] [Accepted: 02/07/2007] [Indexed: 05/07/2023]
Abstract
Wounding, anoxia, and cold are often encountered during crop production and postharvest storage of plant products. Although the effect of these stresses on the expression of sucrose synthase, a key enzyme in the carbon metabolism of many storage organs, has been investigated in several starch-accumulating plant organs, little information on their effect on sucrose synthase expression in sucrose-storing organs is available. To determine the effect of wounding, anoxia and cold on a sucrose-storing organ, sugarbeet (Beta vulgaris) roots were wounded, subjected to anoxic conditions, or exposed to cold temperatures, and transcript and protein levels for the organ's two sucrose synthase genes (SBSS1 and SBSS2) and sucrose synthase enzyme activity were determined during 24h and 7d time course experiments. Wounding, anoxia and cold were associated with several-fold changes in sucrose synthase transcript levels. SBSS1 transcript levels were elevated in wounded, anoxic and cold-treated roots; SBSS2 transcript levels were elevated in response to wounding, cold, and short exposures (3-12h) to anoxic conditions and reduced in roots exposed to anoxic conditions for more than 24h. SBSS1 and SBSS2 protein levels, however, exhibited little change in stressed roots, even after 7d. Enzyme activity was also relatively unchanged in stressed roots, except for small activity differences of 1-2d duration that were unrelated to transcriptional changes. The disparity between transcript levels, protein abundance and enzyme activity indicate that SBSS1 and SBSS2 expression in response to wounding, anoxia and cold may be regulated by post-transcriptional mechanisms. The unresponsiveness of sucrose synthase protein levels or enzyme activity to wounding, anoxia and cold questions the importance of this enzyme to stress responses in sugarbeet root.
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Affiliation(s)
- Karen L Klotz
- USDA-ARS, Northern Crop Science Laboratory, University Station, Fargo, ND 58105-5677, USA.
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Irsigler AST, Costa MDL, Zhang P, Reis PAB, Dewey RE, Boston RS, Fontes EPB. Expression profiling on soybean leaves reveals integration of ER- and osmotic-stress pathways. BMC Genomics 2007; 8:431. [PMID: 18036212 PMCID: PMC2242807 DOI: 10.1186/1471-2164-8-431] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Accepted: 11/23/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Despite the potential of the endoplasmic reticulum (ER) stress response to accommodate adaptive pathways, its integration with other environmental-induced responses is poorly understood in plants. We have previously demonstrated that the ER-stress sensor binding protein (BiP) from soybean exhibits an unusual response to drought. The members of the soybean BiP gene family are differentially regulated by osmotic stress and soybean BiP confers tolerance to drought. While these results may reflect crosstalk between the osmotic and ER-stress signaling pathways, the lack of mutants, transcriptional response profiles to stresses and genome sequence information of this relevant crop has limited our attempts to identify integrated networks between osmotic and ER stress-induced adaptive responses. As a fundamental step towards this goal, we performed global expression profiling on soybean leaves exposed to polyethylene glycol treatment (osmotic stress) or to ER stress inducers. RESULTS The up-regulated stress-specific changes unmasked the major branches of the ER-stress response, which include enhancing protein folding and degradation in the ER, as well as specific osmotically regulated changes linked to cellular responses induced by dehydration. However, a small proportion (5.5%) of total up-regulated genes represented a shared response that seemed to integrate the two signaling pathways. These co-regulated genes were considered downstream targets based on similar induction kinetics and a synergistic response to the combination of osmotic- and ER-stress-inducing treatments. Genes in this integrated pathway with the strongest synergistic induction encoded proteins with diverse roles, such as plant-specific development and cell death (DCD) domain-containing proteins, an ubiquitin-associated (UBA) protein homolog and NAC domain-containing proteins. This integrated pathway diverged further from characterized specific branches of ER-stress as downstream targets were inversely regulated by osmotic stress. CONCLUSION The present ER-stress- and osmotic-stress-induced transcriptional studies demonstrate a clear predominance of stimulus-specific positive changes over shared responses on soybean leaves. This scenario indicates that polyethylene glycol (PEG)-induced cellular dehydration and ER stress elicited very different up-regulated responses within a 10-h stress treatment regime. In addition to identifying ER-stress and osmotic-stress-specific responses in soybean (Glycine max), our global expression-profiling analyses provided a list of candidate regulatory components, which may integrate the osmotic-stress and ER-stress signaling pathways in plants.
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Affiliation(s)
- André ST Irsigler
- Departamento de Bioquímica e Biologia Molecular, BIOAGRO, Universidade Federal de Viçosa, 36571.000 Viçosa, Minas Gerais, Brazil
- Molecular Core Facility, Department of Biology, Florida State University, Tallahassee, FL 32306-4370, USA
| | - Maximiller DL Costa
- Departamento de Bioquímica e Biologia Molecular, BIOAGRO, Universidade Federal de Viçosa, 36571.000 Viçosa, Minas Gerais, Brazil
| | - Ping Zhang
- Department of Crop Science, North Carolina State University, Raleigh, NC 27695, USA
| | - Pedro AB Reis
- Departamento de Bioquímica e Biologia Molecular, BIOAGRO, Universidade Federal de Viçosa, 36571.000 Viçosa, Minas Gerais, Brazil
| | - Ralph E Dewey
- Department of Crop Science, North Carolina State University, Raleigh, NC 27695, USA
| | - Rebecca S Boston
- Department of Plant Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Elizabeth PB Fontes
- Departamento de Bioquímica e Biologia Molecular, BIOAGRO, Universidade Federal de Viçosa, 36571.000 Viçosa, Minas Gerais, Brazil
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Meng M, Geisler M, Johansson H, Mellerowicz EJ, Karpinski S, Kleczkowski LA. Differential tissue/organ-dependent expression of two sucrose- and cold-responsive genes for UDP-glucose pyrophosphorylase in Populus. Gene 2006; 389:186-95. [PMID: 17196771 DOI: 10.1016/j.gene.2006.11.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2006] [Revised: 11/08/2006] [Accepted: 11/08/2006] [Indexed: 10/23/2022]
Abstract
Plant UDP-glucose (UDPG) pyrophosphorylase (UGPase) is involved in the production/metabolism of UDPG, a key metabolite for sucrose and cell wall biosynthesis. Two highly similar cDNAs (UGP1 and UGP2) corresponding to UGPase were isolated from cDNA libraries of hybrid aspen (Populus tremula x tremuloides). Expression of both UGPs, as studied by DNA microarrays and EST abundance, was compared to that of three sucrose synthase genes (SUS1-3), also involved in UDPG synthesis. Generally, the UGPs had lower expression than SUS1 and SUS2 genes (especially in tension wood and cambium), with the notable exception of leaves, primary roots and flowers. Based on real-time quantitative PCR, UGP1 in root xylem, leaves and male flowers was by far the predominant transcript, while in other tissues both UGP1 and UGP2 had comparable expression. In leaves, the UGP1 gene, but not UGP2, was upregulated by light and short-term sucrose feeding. Cold treatment led to dramatic organ-specific changes in relative expression of both genes, with UGP2 being upregulated either transiently (leaves), long-term (stems) or not at all (roots), whereas UGP1 was cold-upregulated in all organs. Individual or overall UGP expression patterns only weakly correlated with UGPase activity/protein; however, UGPase activity and protein were correlated in all tissues/conditions. The data suggest that UGPs are differentially expressed at the tissue level and in response to metabolic feedback (sucrose) and cold stress, and point to a tight posttranscriptional/translational control and, possibly, distinct roles for those genes.
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Affiliation(s)
- Meng Meng
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, 901 87 Umeå, Sweden
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Buitink J, Leger JJ, Guisle I, Vu BL, Wuillème S, Lamirault G, Le Bars A, Le Meur N, Becker A, Küster H, Leprince O. Transcriptome profiling uncovers metabolic and regulatory processes occurring during the transition from desiccation-sensitive to desiccation-tolerant stages in Medicago truncatula seeds. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 47:735-50. [PMID: 16923015 DOI: 10.1111/j.1365-313x.2006.02822.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
To investigate regulatory processes and protective mechanisms leading to desiccation tolerance (DT) in seeds, 16086-element microarrays were used to monitor changes in the transcriptome of desiccation-sensitive 3-mm-long radicles of Medicago truncatula seeds at different time points during incubation in a polyethylene glycol (PEG) solution at -1.7 MPa, resulting in a gradual re-establishment of DT. Gene profiling was also performed on embryos before and after the acquisition of DT during maturation. More than 1300 genes were differentially expressed during the PEG incubation. A large number of genes involved in C metabolism are expressed during the re-establishment of DT. Quantification of C reserves confirms that lipids, starch and oligosaccharides were mobilised, coinciding with the production of sucrose during the early osmotic adjustment. Several clusters of gene profiles were identified with different time-scales. Genes expressed early during the PEG incubation belonged to classes involved in early stress and adaptation responses. Interestingly, several regulatory genes typically expressed during abiotic/drought stresses were also upregulated during maturation, arguing for the partial overlap of ABA-dependent and -independent regulatory pathways involved in both drought and DT. At later time points, in parallel to the re-establishment of DT, upregulated genes are comparable with those involved in late seed maturation. Concomitantly, a massive repression of genes belonging to numerous classes occurred, including cell cycle, biogenesis, primary and energy metabolism. The re-establishment of DT in the germinated radicles appears to concur with a partial return to the quiescent state prior to germination.
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Affiliation(s)
- Julia Buitink
- Unité Mixte de Recherche 1191 Physiologie Moléculaire des Semences, Université d'Angers/INH/INRA, 16 Bd Lavoisier, 49045 Angers, France
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Coleman HD, Ellis DD, Gilbert M, Mansfield SD. Up-regulation of sucrose synthase and UDP-glucose pyrophosphorylase impacts plant growth and metabolism. PLANT BIOTECHNOLOGY JOURNAL 2006; 4:87-101. [PMID: 17177788 DOI: 10.1111/j.1467-7652.2005.00160.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The effects of the overexpression of sucrose synthase (SuSy) and UDP-glucose pyrophosphorylase (UGPase) on plant growth and metabolism were evaluated in tobacco (Nicotiana tabacum cv. Xanthi). T(1) transgenic plants expressing either gene under the control of a tandem repeat cauliflower mosaic virus 35S promoter (2x35S) or a xylem-localized 4CL promoter (4-coumarate:CoA ligase; 4CL) were generated, and reciprocally crossed to generate plants expressing both genes. Transcript levels, enzyme activity, growth parameters, fibre properties and carbohydrate content of stem tissue were quantified. The expression profiles of both genes confirmed the expression pattern of the promoters: 2x35S expressed more strongly in leaves, while 4CL expression was highest in stem tissue. In-depth plant characterization revealed that the single-transgene lines showed significant increases in the height growth compared with corresponding control lines. The double-transgene plants demonstrated an additive effect, proving to be even taller than the single-transgene parents. Several of these lines had associated increases in soluble sugar content. Although partitioning of storage carbohydrates into starch or cellulose was not observed, the increased height growth and increases in soluble carbohydrates suggest a role for SuSy as a marker in sink strength and lend credit to the function of UGPase in a similar role. The up-regulation of these two genes, although not increasing the percentage cellulose content, was effective in increasing the total biomass, and thus the overall cellulose yield, from a given plant.
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Affiliation(s)
- Heather D Coleman
- Department of Wood Science, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
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GONZALI SILVIA, LORETI ELENA, NOVI GIACOMO, POGGI ALESSANDRA, ALPI AMEDEO, PERATA PIERDOMENICO. The use of microarrays to study the anaerobic response in Arabidopsis. ANNALS OF BOTANY 2005; 96:661-8. [PMID: 16033780 PMCID: PMC4247033 DOI: 10.1093/aob/mci218] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND AND AIMS The use of microarrays to characterize the transcript profile of Arabidopsis under various experimental conditions is rapidly expanding. This technique provides a huge amount of expression data, requiring bioinformatics tools to allow the proposal of working hypotheses. The aim of this study was to test the usefulness of this approach to examine the anaerobic response of Arabidopsis by evaluating the reliability of microarray data sets and by interrogation of microarray databases for the expression data of a set of anoxia-inducible genes. METHODS User-driven software tools that display large gene expression datasets onto diagrams of metabolic pathways were used. The Genevestigator software was used to explore the expression of anoxia-inducible genes throughout the life cycle of Arabidopsis as well as relative to plant organs. T-DNA tagged mutants for selected genes identified from our microarray analysis were searched in the Arabidopsis thaliana Insertion Database, looking for insertional mutants from the Salk collection. KEY RESULTS The results indicate that microarray data can provide the basis for new hypotheses in the field of plant responses to anaerobiosis and also provide knowledge for a targeted screening of Arabidopsis mutants. CONCLUSIONS Research on plant responses to anaerobiosis can enormously benefit from the microarray technology.
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Affiliation(s)
- SILVIA GONZALI
- Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, 56124 Pisa, Italy
| | - ELENA LORETI
- Institute of Biology and Agricultural Biotechnology, CNR, Via del Borghetto 80, 56100 Pisa, Italy
| | - GIACOMO NOVI
- Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, 56124 Pisa, Italy
| | - ALESSANDRA POGGI
- Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, 56124 Pisa, Italy
| | - AMEDEO ALPI
- Department of Crop Plant Biology, University of Pisa, Via Mariscoglio 34, 56124 Pisa, Italy
| | - PIERDOMENICO PERATA
- Sant'Anna School of Advanced Studies, Piazza Martiri della Libertà, 33, 56127 Pisa, Italy
- For correspondence. E-mail
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Masaki T, Mitsui N, Tsukagoshi H, Nishii T, Morikami A, Nakamura K. ACTIVATOR of Spomin::LUC1/WRINKLED1 of Arabidopsis thaliana Transactivates Sugar-inducible Promoters. ACTA ACUST UNITED AC 2005; 46:547-56. [PMID: 15753106 DOI: 10.1093/pcp/pci072] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We isolated an enhancer activation-tagged mutant of Arabidopsis thaliana line sGsL carrying the luciferase (LUC) gene under control of a short sugar-inducible promoter derived from a sweet potato sporamin gene (Spomin) that showed high level expression of LUC under non-inducing conditions. The activator of Spomin::LUC1 (ASML1) gene located downstream of the enhancer encoded an APETALA2 (AP2)-type AP2 domain protein, and this gene was shown recently to be responsible for the wrinkled1 mutation which causes defective accumulation of seed storage oil. Overexpression of ASML1 cDNA in sGsL plants resulted in enhanced expression of not only the LUC reporter but also endogenous sugar-inducible genes including Atbeta-Amy encoding beta-amylase. Transient co-expression of 35S::ASML1 with Spomin::LUC or Atbeta-Amy::LUC reporters in protoplasts resulted in an approximately 10-fold transactivation of LUC expression. This transactivation was lost when the C-terminal acidic region of ASML1 was deleted. Expression of ASML1 was high in reproductive organs, and ASML1 mRNA showed transient accumulation in leaves after treatment with 6% sucrose, whereas it did not respond to abscisic acid. These results suggest that ASML1/WRI1 is a transcriptional activator involved in the activation of a subset of sugar-responsive genes and the control of carbon flow from sucrose import to oil accumulation in developing seeds.
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Affiliation(s)
- Takeshi Masaki
- Laboratory of Biochemistry, Graduate School of Bioagricultural Science, Nagoya University, Chikusa, Nagoya, 464-8601 Japan
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Dóczi R, Kondrák M, Kovács G, Beczner F, Bánfalvi Z. Conservation of the drought-inducible DS2 genes and divergences from their ASR paralogues in solanaceous species. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2005; 43:269-76. [PMID: 15854835 DOI: 10.1016/j.plaphy.2005.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Accepted: 02/04/2005] [Indexed: 05/08/2023]
Abstract
The drought-inducible DS2 genes of potatoes are members of the ASR (abscisic acid, stress and ripening) gene family. Previously it was shown that expression of DS2 genes is highly dehydration-specific in potato leaves, is not inducible by cold, heat, salt, hypoxia or oxidative stresses, and is independent of abscisic acid (ABA). Now it is shown that StDS2 does not respond either to sucrose or any plant hormones. Conservation of DS2 genes with this unique mode of regulation was studied in the solanaceous species with different relationships to potatoes. DS2 orthologues were identified by DNA sequence alignment in the closely related Lycopersicon and Capsicum species but not in the more distantly related Nicotiana sp. DNA and RNA gel blot analysis revealed the presence of a gene highly homologous to the potato gene StDS2 in tomato (LeDS2) with the same desiccation-specific expression in leaves and organ-specific expression in flowers and green fruits. The LeDS2 promoter was isolated and found to be almost identical in sequence with the promoter of StDS2, except for a 45-bp insertion in tomato. In contrast, no gene highly similar to StDS2 was detected in Nicotiana species on DNA gel blots. Neither StDS2 nor LeDS2 promoter regions were able to confer expression for the beta-glucuronidase (GUS) reporter gene in transgenic tobacco plants indicating that the trans regulatory factors necessary for DS2 expression are not conserved either in Nicotiana tabacum. These data suggest a narrow species-specificity and late evolution of the DS2-type genes within the family Solanaceae.
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Affiliation(s)
- Róbert Dóczi
- Agricultural Biotechnology Center, P.O. Box 411, H-2101 Gödöllö, Hungary
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Schäfer WE, Rohwer JM, Botha FC. Partial purification and characterisation of sucrose synthase in sugarcane. JOURNAL OF PLANT PHYSIOLOGY 2005; 162:11-20. [PMID: 15700416 DOI: 10.1016/j.jplph.2004.04.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Three sucrose synthase (SuSy) (EC 2.4.1.13) forms were isolated from sugarcane leaf roll tissue. During anion exchange chromatography, one peak of activity (SuSyA) eluted during the wash step and the other peak (SuSyB) during the salt gradient phase at 180mM KCl concentration. A third form of activity (SuSyC), which also eluted at 180mM KCl, was also present in the leaf roll and replaced SuSyB depending on the season of the year. Substrate Km values, as well as sucrose breakdown/synthesis ratios, differed between these forms. For SuSyA, SuSyB, and SuSyC, respectively, Km values+/-SE (mM) were: 41.8+/-3.4, 109+/-23, and 35.9+/-2.3 for sucrose, 1.07+/-0.08, 0.214+/-0.039, and 0.00191+/-0.00019 for UDP, 6.62+/-1.55, 11.7+/-2.6, and 6.49+/-0.61 for fructose, and 3.59+/-0.37, 0.530+/-0.142, and 0.234+/-0.025 for UDP-glucose. Sucrose breakdown/synthesis ratios+/-SE were 0.0791+/-0.0199, 0.330+/-0.180, and 0.426+/-0.069 for SuSyA, SuSyB, and SuSyC, respectively. The ratio of the area of peak 1 (low breakdown/synthesis ratio) to the area of peak 2 (high breakdown/synthesis ratio) in sucrose accumulating tissue (internode 9) was 0.88, while in non-accumulating (leaf roll) tissue it was 14.5 at the same time of year. The molecular mass of the denatured subunits of all three forms was 94kDa by SDS-PAGE. A polyclonal antiserum raised against SuSyB cross-reacted with all three forms on an immunoblot, but only SuSyA and SuSyB were immunoinactivated by this serum.
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Affiliation(s)
- Wolfgang E Schäfer
- Institute for Plant Biotechnology, University of Stellenbosch, 7602 Matieland, South Africa.
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Matic S, Akerlund HE, Everitt E, Widell S. Sucrose synthase isoforms in cultured tobacco cells. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2004; 42:299-306. [PMID: 15120114 DOI: 10.1016/j.plaphy.2004.01.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2003] [Accepted: 01/24/2004] [Indexed: 05/24/2023]
Abstract
The plant enzyme sucrose synthase (SuSy; EC 2.4.1.13) catalyzes the reversible conversion of sucrose and UDP into UDP-glucose (UDP-Glc) and fructose. The enzyme exists in different isoforms and is both located in the cytosol, membrane-bound and associated to the actin cytoskeleton. We here investigate sucrose synthase from tobacco (Nicotiana tabacum L.) BY-2 heterotrophic cell suspensions. Two different isoforms of sucrose synthase SuSy1 and SuSy2, could be purified from cytosolic extracts of these cells using a combination of poly(ethylene glycol) (PEG) precipitation, gel filtration, ion-exchange chromatography and affinity chromatography. They were clearly distinct, both with regard to the binding to the ion-exchange column and with regard to their kinetic and regulatory properties. SuSy1, the more abundant species, showed lower V(max) and K(m) for sucrose and UDP compared to the less abundant SuSy2. The activity of SuSy2 in the breakdown direction was stimulated by 60% by actin, in contrast to that of SuSy1, which showed a 17% inhibition. An indication of interaction between SuSy1 and actin was obtained by partitioning in aqueous Dextran-PEG two-phase systems. Furthermore, fructose 2,6-bisphosphate (F26BP) at micromolar concentrations stimulated SuSy2 in the presence of actin while SuSy1 was strongly inhibited by fructose. Possible roles of these two isoforms in the sucrose turnover in BY-2 cells are discussed.
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Affiliation(s)
- Sandra Matic
- Department of Cell and Organism Biology, Lund University, Sölvegatan 35B, 22362 Lund, Sweden.
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Baud S, Vaultier MN, Rochat C. Structure and expression profile of the sucrose synthase multigene family in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2004; 55:397-409. [PMID: 14739263 DOI: 10.1093/jxb/erh047] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The release of the complete genome sequence of Arabidopsis enabled the largest sucrose synthase family described to date, comprising six distinct members, for which expression profiles were not yet available, to be identified. Aimed at understanding the precise function of each AtSUS member among the family, a comparative study of protein structure was performed, together with an expression profiling of the whole gene family using the technique of real-time quantitative reverse transcriptase-polymerase chain reaction. Transcript levels were analysed in several plant organs, including both developing and germinating seeds. A series of treatments such as oxygen deprivation, dehydration, cold treatment, or various sugar feedings were then carried out to characterize the members of the family further. The AtSUS genes exhibit distinct but partially redundant expression profiles. Under anaerobic conditions, for instance, both AtSUS1 and AtSUS4 mRNA levels increase, but in a distinct manner. AtSUS2 is specifically and highly induced in seeds at 12 d after flowering and appears as a marker of seed maturation. AtSUS3 seems to be induced in various organs under dehydration conditions including leaves deprived of water or submitted to osmotic stress as well as late-maturing seeds. AtSUS5 and AtSUS6 are expressed in nearly all plant organs and do not exhibit any transcriptional response to stresses. These results add new insights on the expression of SUS genes and are discussed in relation to distinct functions for each member of the AtSUS family.
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Affiliation(s)
- Sébastien Baud
- Unité de Biologie des Semences, UMR 204, INA-PG-INRA, RD 10, 78026 Versailles cedex, France
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Siedlecka A, Ciereszko I, Mellerowicz E, Martz F, Chen J, Kleczkowski LA. The small subunit ADP-glucose pyrophosphorylase ( ApS) promoter mediates okadaic acid-sensitive uidA expression in starch-synthesizing tissues and cells in Arabidopsis. PLANTA 2003; 217:184-192. [PMID: 12783326 DOI: 10.1007/s00425-003-0982-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2002] [Accepted: 12/23/2002] [Indexed: 05/24/2023]
Abstract
Transgenic plants of Arabidopsis thaliana Heynh., transformed with a bacterial beta-glucuronidase (GUS) gene under the control of the promoter of the small subunit (ApS) of ADP-glucose pyrophosphorylase (AGPase), exhibited GUS staining in leaves (including stomata), stems, roots and flowers. Cross-sections of stems revealed GUS staining in protoxylem parenchyma, primary phloem and cortex. In young roots, the staining was found in the root tips, including the root cap, and in vascular tissue, while the older root-hypocotyl axis showed prominent staining in the secondary phloem and paratracheary parenchyma of secondary xylem. The GUS staining co-localized with ApS protein, as found by tissue printing using antibodies against ApS. Starch was found only in cell and tissue types exhibiting GUS staining and ApS labelling, but not in all of them. For example, starch was lacking in the xylem parenchyma and secondary phloem of the root-hypocotyl axis. Sucrose potently activated ApS gene expression in leaves of wild-type (wt) plants, and in transgenic seedlings grown on sucrose medium where GUS activity was quantified with 4-methylumbelliferyl-beta-glucuronide as substrate. Okadaic acid, an inhibitor of protein phosphatases 1 and 2A, completely blocked expression of ApS in mature leaves of wt plants and prevented GUS staining in root tips and flowers of the transgenic plants, suggesting a similar signal transduction mechanism for ApS expression in various tissues. The data support the key role of AGPase in starch synthesis, but they also underlie the ubiquitous importance of the ApS gene for AGPase function in all organs/tissues of Arabidopsis.
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Affiliation(s)
- Anna Siedlecka
- Department of Plant Physiology, Maria Curie-Sklodowska University, 20-033, Lublin, Poland
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Ciereszko I, Kleczkowski LA. Effects of phosphate deficiency and sugars on expression of rab18 in Arabidopsis: hexokinase-dependent and okadaic acid-sensitive transduction of the sugar signal. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1579:43-9. [PMID: 12401218 DOI: 10.1016/s0167-4781(02)00502-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The lack of phosphorus in the nutrient medium increased the expression of rab18, an abscisic acid (ABA)-responsive gene, in leaves of Arabidopsis thaliana. The expression of this gene was also upregulated after feeding the excised leaves with D-mannose and sucrose for both wild-type (wt) and aba1 (ABA-deficient) mutant plants. For aba1 mutants, both the phosphate deficiency and sugar effects on rab18 were weaker than in wt plants, suggesting possible involvement of both ABA-dependent and ABA-independent components in signalling. Transgenic Arabidopsis plants with increased hexokinase (HXK) expression had a much higher sucrose-dependent level of rab18 mRNA, implying the HXK involvement in sensing/transmitting the sugar signal. Sucrose-related induction of rab18 was completely inhibited by okadaic acid (OKA), suggesting the involvement of specific protein phosphatase(s) in transduction of the sugar signal. The results suggest that rab18 is regulated via interaction of a plethora of signals, including ABA, sugar and phosphate deficiency, and that the sugar effect is transmitted via a HXK-pathway, involving OKA-sensitive component(s). The findings prompt caution in linking the expression of rab18 solely to ABA signalling.
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Affiliation(s)
- Iwona Ciereszko
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, 901 87 Umeå, Sweden.
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Johansson H, Sterky F, Amini B, Lundeberg J, Kleczkowski LA. Molecular cloning and characterization of a cDNA encoding poplar UDP-glucose dehydrogenase, a key gene of hemicellulose/pectin formation. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1576:53-8. [PMID: 12031484 DOI: 10.1016/s0167-4781(02)00292-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Plant UDP-glucose dehydrogenase (UGDH) is an important enzyme in the formation of hemicellulose and pectin, the components of newly formed cell walls. A cDNA clone (Ugdh) corresponding to UGDH was isolated from a cDNA library prepared from cambial zone of poplar (Populus tremula x tremuloides). Within the 1824-nucleotide (nt)-long clone, an open reading frame encoded a protein of 481 amino acids (aa), with a calculated molecular weight of 53.1 kDa. The derived aa sequence showed 90% and 63% identity with UGDHs from soybean and bovine liver, respectively, and had highly conserved aa motifs believed to be of importance for nt binding and catalytic efficiency. In poplar, the Ugdh corresponds to one or two genes, as found by genomic Southern analysis. The gene was expressed predominantly in differentiating xylem and young leaves, with little expression in the phloem zone of the stem. The expression pattern matched that of UGDH protein, as found by immunoblotting. In leaves, the Ugdh expression was upregulated by a short-term feeding with sucrose, sorbitol and polyethylene glycol, and this effect was to some extent mimicked by light exposure. The data suggest that Ugdh is regulated via an osmoticum-dependent pathway, possibly related to the availability of osmotically active carbohydrate precursors to UDP-glucose, a substrate of UGDH.
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Affiliation(s)
- Henrik Johansson
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, 901-87, Umeå, Sweden
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González EM, Gálvez L, Arrese-Igor C. Abscisic acid induces a decline in nitrogen fixation that involves leghaemoglobin, but is independent of sucrose synthase activity. JOURNAL OF EXPERIMENTAL BOTANY 2001; 52:285-93. [PMID: 11283173 DOI: 10.1093/jexbot/52.355.285] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Sucrose synthase (SS) activity has been suggested to be a key point of regulation in nodule metabolism since this enzyme is down-regulated in response to different stresses which lead to decreased nitrogen fixation. In soybean, a dramatic decline of SS transcripts has been observed within 1 d from the onset of drought. Such a quick response suggests mediation by a signal transduction molecule. Abscisic acid (ABA) is a likely candidate to act as such a molecule as it mediates in a significant number of plant responses to environmental constraints. The hypothesis of ABA controlling nodule metabolism was approached in this work by assessing nodule responses to exogenous ABA supply in pea. Under the experimental conditions, ABA did not affect plant biomass, nodule numbers or dry weight. However, nitrogen fixation rate was reduced by 70% within 5 d and by 80% after 9 d leading to a reduced plant organic nitrogen content. Leghaemoglobin (Lb) content declined in parallel with that of nitrogen fixation. SS activity, however, was not affected by ABA treatment, and neither were the activities of the enzymes aspartate amino transferase, alkaline invertase, malate dehydrogenase, glutamate synthase, uridine diphosphoglucose pyrophosphorylase, isocitrate dehydrogenase, and glutamine synthetase. Nodule bacteroid-soluble protein content was reduced in nodules only after 9 d of ABA treatment. These results do not support the hypothesis that ABA directly regulates SS activity. However, they do suggest the occurrence of at least two different control pathways in nodules under environmental constraints, which include ABA being involved in a Lb/oxygen-related control of nitrogen fixation.
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Affiliation(s)
- E M González
- Departamento de Ciencias del Medio Natural, Universidad Pública de Navarra, Campus de Arrosadía, E-31006 Pamplona, Spain
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