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Mao Z, Wang Y, Li M, Zhang S, Zhao Z, Xu Q, Liu JH, Li C. Vacuolar proteomic analysis reveals tonoplast transporters for accumulation of citric acid and sugar in citrus fruit. HORTICULTURE RESEARCH 2024; 11:uhad249. [PMID: 38288255 PMCID: PMC10822839 DOI: 10.1093/hr/uhad249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 11/13/2023] [Indexed: 01/31/2024]
Abstract
Vacuole largely dictates the fruit taste and flavor, as most of the sugars and organic acids are stored in the vacuoles of the fruit. However, difficulties associated with vacuole separation severely hinder identification and characterization of vacuolar proteins in fruit species. In this study, we established an effective approach for separating vacuoles and successfully purified vacuolar protein from six types of citrus fruit with varying patterns of sugar and organic acid contents. By using label-free LC-MS/MS proteomic analysis, 1443 core proteins were found to be associated with the essential functions of vacuole in citrus fruit. Correlation analysis of metabolite concentration with proteomic data revealed a transporter system for the accumulation of organic acid and soluble sugars in citrus. Furthermore, we characterized the physiological roles of selected key tonoplast transporters, ABCG15, Dict2.1, TMT2, and STP7 in the accumulation of citric acid and sugars. These findings provide a novel perspective and practical solution for investigating the transporters underlying the formation of citrus taste and flavor.
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Affiliation(s)
- Zuolin Mao
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Yue Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Mengdi Li
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Shuhang Zhang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Zeqi Zhao
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Qiang Xu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Ji-Hong Liu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Chunlong Li
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
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Atamian HS, Funk JL. Physiological and transcriptomic responses of two Artemisia californica populations to drought: implications for restoring drought-resilient native communities. Glob Ecol Conserv 2023. [DOI: 10.1016/j.gecco.2023.e02466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023] Open
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Cai YS, Cai JL, Lee JT, Li YM, Balladona FK, Sukma D, Chan MT. Arabidopsis AtMSRB5 functions as a salt-stress protector for both Arabidopsis and rice. FRONTIERS IN PLANT SCIENCE 2023; 14:1072173. [PMID: 37035039 PMCID: PMC10073502 DOI: 10.3389/fpls.2023.1072173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 03/06/2023] [Indexed: 06/19/2023]
Abstract
Salinity, drought and low temperature are major environmental factors that adversely affect crop productivity worldwide. In this study we adopted an activation tagging approach to identify salt tolerant mutants of Arabidopsis. Thousands of tagged Arabidopsis lines were screened to obtain several potential mutant lines resistant to 150 mM NaCl. Transcript analysis of a salt-stress tolerance 1 (sst1) mutant line indicated activation of AtMSRB5 and AtMSRB6 which encode methionine sulfoxide reductases. Overexpression of AtMSRB5 in Arabidopsis (B5OX) showed a similar salt tolerant phenotype. Furthermore, biochemical analysis indicated stability of the membrane protein, H+-ATPase 2 (AHA2) through regulation of Na+/K+ homeostasis which may be involved in a stress tolerance mechanism. Similarly, overexpression of AtMSRB5 in transgenic rice demonstrated a salt tolerant phenotype via the modulation of Na+/K+ homeostasis without a yield drag under salt and oxidative stress conditions.
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Affiliation(s)
- Yu-Si Cai
- Graduate Program of Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, Tainan, Taiwan
| | - Jung-Long Cai
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, Tainan, Taiwan
| | - Jent-Turn Lee
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, Tainan, Taiwan
| | - Yi-Min Li
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, Tainan, Taiwan
| | - Freta Kirana Balladona
- Graduate Program of Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, Tainan, Taiwan
| | - Dewi Sukma
- Department of Agronomy & Horticulture, Faculty of Agriculture, IPB University, Bogor, Indonesia
| | - Ming-Tsair Chan
- Graduate Program of Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Tainan, Taiwan
- Academia Sinica Biotechnology Center in Southern Taiwan, Agricultural Biotechnology Research Center, Academia Sinica, Tainan, Taiwan
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Wink M. Current Understanding of Modes of Action of Multicomponent Bioactive Phytochemicals: Potential for Nutraceuticals and Antimicrobials. Annu Rev Food Sci Technol 2022; 13:337-359. [PMID: 35333591 DOI: 10.1146/annurev-food-052720-100326] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Plants produce a diversity of plant secondary metabolites (PSMs), which function as defense chemicals against herbivores and microorganisms but also as signal compounds. An individual plant produces and accumulates mixtures of PSMs with different structural features using different biosynthetic pathways. Almost all PSMs exert one or several biological activities that can be useful for nutrition and health. This review discusses the modes of action of PSMs alone and in combinations. In a mixture, most individual PSMs can modulate different molecular targets; they are thus multitarget drugs. In an extract with many multitarget chemicals, additive and synergistic effects occur. Experiments with the model system Caenorhabditis elegans show that polyphenols and carotenoids can function as powerful antioxidative and longevity-promoting PSMs. PSMs of food plants and spices often exhibit antioxidant, anti-inflammatory, and antimicrobial properties, which can be beneficial for health and the prevention of diseases. Some extracts from food plants and spices with bioactive PSMs have potential for nutraceuticals and antimicrobials.
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Affiliation(s)
- Michael Wink
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany;
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Al-Mushhin AAM, Qari SH, Fakhr MA, Alnusairi GSH, Alnusaire TS, ALrashidi AA, Latef AAHA, Ali OM, Khan AA, Soliman MH. Exogenous Myo-Inositol Alleviates Salt Stress by Enhancing Antioxidants and Membrane Stability via the Upregulation of Stress Responsive Genes in Chenopodium quinoa L. PLANTS (BASEL, SWITZERLAND) 2021; 10:2416. [PMID: 34834781 PMCID: PMC8623490 DOI: 10.3390/plants10112416] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 05/15/2023]
Abstract
Myo-inositol has gained a central position in plants due to its vital role in physiology and biochemistry. This experimental work assessed the effects of salinity stress and foliar application of myo-inositol (MYO) on growth, chlorophyll content, photosynthesis, antioxidant system, osmolyte accumulation, and gene expression in quinoa (Chenopodium quinoa L. var. Giza1). Our results show that salinity stress significantly decreased growth parameters such as plant height, fresh and dry weights of shoot and root, leaf area, number of leaves, chlorophyll content, net photosynthesis, stomatal conductance, transpiration, and Fv/Fm, with a more pronounced effect at higher NaCl concentrations. However, the exogenous application of MYO increased the growth and photosynthesis traits and alleviated the stress to a considerable extent. Salinity also significantly reduced the water potential and water use efficiency in plants under saline regime; however, exogenous application of myo-inositol coped with this issue. MYO significantly reduced the accumulation of hydrogen peroxide, superoxide, reduced lipid peroxidation, and electrolyte leakage concomitant with an increase in the membrane stability index. Exogenous application of MYO up-regulated the antioxidant enzymes' activities and the contents of ascorbate and glutathione, contributing to membrane stability and reduced oxidative damage. The damaging effects of salinity stress on quinoa were further mitigated by increased accumulation of osmolytes such as proline, glycine betaine, free amino acids, and soluble sugars in MYO-treated seedlings. The expression pattern of OSM34, NHX1, SOS1A, SOS1B, BADH, TIP2, NSY, and SDR genes increased significantly due to the application of MYO under both stressed and non-stressed conditions. Our results support the conclusion that exogenous MYO alleviates salt stress by involving antioxidants, enhancing plant growth attributes and membrane stability, and reducing oxidative damage to plants.
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Affiliation(s)
- Amina A. M. Al-Mushhin
- Department of Biology, College of Science and Humanities in Al-Kharj, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia;
| | - Sameer H. Qari
- Biology Department, Al-Jumum University College, Umm Al-Qura University, Mecca 21955, Saudi Arabia;
| | - Marwa A. Fakhr
- Botany Department, Faculty of Science, Fayoum University, Fayoum 63514, Egypt;
- Plant Protection and Bimolecular Diagnosis Department, Arid Lands Cultivation Research Institute, City of Scientific Research and Technological Application (SRTA-city), New Borg El-Arab City 21934, Egypt
| | - Ghalia S. H. Alnusairi
- Department of Biology, College of Science, Jouf University, Sakaka 2014, Saudi Arabia; (G.S.H.A.); (T.S.A.)
| | - Taghreed S. Alnusaire
- Department of Biology, College of Science, Jouf University, Sakaka 2014, Saudi Arabia; (G.S.H.A.); (T.S.A.)
| | - Ayshah Aysh ALrashidi
- Department of Biology, Faculty of Science, University of Hail, Hail 81411, Saudi Arabia;
| | | | - Omar M. Ali
- Department of Chemistry, Turabah University College, Turabah Branch, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia;
| | - Amir Abdullah Khan
- Department of Plant Biology and Ecology, Nankai University, Tianjin 300071, China
| | - Mona H. Soliman
- Botany and Microbiology Department, Faculty of Science, Cairo University, Giza 12613, Egypt;
- Biology Department, Faculty of Science, Taibah University, Al-Sharm, Yanbu El-Bahr, Yanbu 46429, Saudi Arabia
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Khoudi H. Significance of vacuolar proton pumps and metal/H + antiporters in plant heavy metal tolerance. PHYSIOLOGIA PLANTARUM 2021; 173:384-393. [PMID: 33937997 DOI: 10.1111/ppl.13447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/16/2021] [Accepted: 04/29/2021] [Indexed: 06/12/2023]
Abstract
Soil and water are among the most valuable resources on earth. Unfortunately, their contamination with heavy metals has become a global problem. Heavy metals are not biodegradable and cannot be chemically degraded; therefore, they tend to accumulate in soils or to be transported by streaming water and contaminate both surface and groundwater. Cadmium (Cd) has no known biological function but is one of the most toxic metals. It represents a serious environmental concern since its accumulation in soils is associated with health risks to plants, animals and humans. On the other hand, copper (Cu) and zinc (Zn) are heavy metals that are indispensable to plants but become toxic when their concentration in soils exceeds a certain optimal level. Plants have evolved many mechanisms to cope with heavy metal toxicity; vacuolar sequestration is one of them. Vacuolar sequestration can be achieved through either phytochelatin-dependent or phytochelatin-independent pathways. Most of the transgenic plants meant for phytoremediation described in the literature result from the manipulation of genes involved in the phytochelatin-dependent pathway. However, recent evidence has emerged to support the importance of the phytochelatin-independent pathway in heavy metal sequestration into the vacuole, with metal/H+ antiporters and proton pumps playing an important role. In this review, the importance of vacuolar proton pumps and metal/H+ antiporters transporting Cd, Cu, and Zn is discussed. In addition, the recent advances in the production of transgenic plants with potential application in phytoremediation and food safety through the manipulation of genes encoding V-PPase proton pumps is described.
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Affiliation(s)
- Habib Khoudi
- Laboratory of Plant Biotechnology and Improvement, Center of Biotechnology of Sfax (CBS), University of Sfax, Sfax, Tunisia
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Ovrutska I. Aquaporins in regulation of plant protective responses to drought. UKRAINIAN BOTANICAL JOURNAL 2021. [DOI: 10.15407/ukrbotj78.03.221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Plasmolemma permeability is an integral indicator of the functional state of plant cells under stress. Aquaporins (AQPs), specialized transmembrane proteins that form water channels and play an important role in the adaptation of plants to adverse conditions and, in particular, to lack or excess of water, are involved in the formation of the response to drought. The main function of AQPs is to facilitate the movement of water across cell membranes and maintain aqueous cell homeostasis. Under stressful conditions, there is both an increase and decrease in the expression of individual aquaporin genes. Analysis of the data revealed differences in the expression of AQPs genes in stable and sensitive plant genotypes. It turned out that aquaporins in different stress-resistant varieties of the same species also respond differently to drought. The review provides brief information on the history of the discovery of aquaporins, the structure and function of these proteins, summarizes the latest information on the role of aquaporins in the regulation of metabolism and the response of plants to stressors, with particular emphasis on aquaporins in drought protection. The discovery and study of AQPs expands the possibilities of using genetic engineering methods for the selection of new plant species, in particular, more resistant to drought and salinization of the soil, as well as to increase their productivity. The use of aquaporins in biotechnology to improve drought resistance of various species has many prospects.
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Molecular characterization and transcriptional regulation of two types of H +-pyrophosphatases in the scuticociliate parasite Philasterides dicentrarchi. Sci Rep 2021; 11:8519. [PMID: 33875762 PMCID: PMC8055999 DOI: 10.1038/s41598-021-88102-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 04/08/2021] [Indexed: 02/02/2023] Open
Abstract
Proton-translocating inorganic pyrophosphatases (H+-PPases) are an ancient family of membrane bound enzymes that couple pyrophosphate (PPi) hydrolysis to H+ translocation across membranes. In this study, we conducted a molecular characterization of two isoenzymes (PdVP1 and PdVP2) located in respectively the alveolar sacs and in the membranes of the intracellular vacuoles of a scuticociliate parasite (Philasterides dicentrarchi) of farmed turbot. We analyzed the genetic expression of the isoenzymes after administration of antiparasitic drugs and after infection in the host. PdVP1 and PdVP2 are encoded by two genes of 2485 and 3069 bp, which respectively contain 3 and 11 exons and express proteins of 746 and 810 aa of molecular mass 78.9 and 87.6 kDa. Topological predictions from isoenzyme sequences indicate the formation of thirteen transmembrane regions (TMRs) for PdVP1 and seventeen TMRs for PdVP2. Protein structure modelling indicated that both isoenzymes are homodimeric, with three Mg2+ binding sites and an additional K+ binding site in PdVP2. The levels of identity and similarity between the isoenzyme sequences are respectively 33.5 and 51.2%. The molecular weights of the native proteins are 158 kDa (PdVP1) and 178 kDa (PdVP2). The isoenzyme sequences are derived from paralogous genes that form a monophyletic grouping with other ciliate species. Genetic expression of the isoenzymes is closely related to the acidification of alveolar sacs (PdVP1) and intracellular vacuoles (PdVP2): antiparasitic drugs inhibit transcription, while infection increases transcription of both isoenzymes. The study findings show that P. dicentrarchi possesses two isoenzymes with H+-PPase activity which are located in acidophilic cell compartment membranes and which are activated during infection in the host and are sensitive to antiparasitic drugs. The findings open the way to using molecular modelling to design drugs for the treatment of scuticociliatosis.
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Cosse M, Seidel T. Plant Proton Pumps and Cytosolic pH-Homeostasis. FRONTIERS IN PLANT SCIENCE 2021; 12:672873. [PMID: 34177988 PMCID: PMC8220075 DOI: 10.3389/fpls.2021.672873] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/15/2021] [Indexed: 05/06/2023]
Abstract
Proton pumps create a proton motif force and thus, energize secondary active transport at the plasma nmembrane and endomembranes of the secretory pathway. In the plant cell, the dominant proton pumps are the plasma membrane ATPase, the vacuolar pyrophosphatase (V-PPase), and the vacuolar-type ATPase (V-ATPase). All these pumps act on the cytosolic pH by pumping protons into the lumen of compartments or into the apoplast. To maintain the typical pH and thus, the functionality of the cytosol, the activity of the pumps needs to be coordinated and adjusted to the actual needs. The cellular toolbox for a coordinated regulation comprises 14-3-3 proteins, phosphorylation events, ion concentrations, and redox-conditions. This review combines the knowledge on regulation of the different proton pumps and highlights possible coordination mechanisms.
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Hussain SB, Shi CY, Guo LX, Du W, Bai YX, Kamran HM, Fernie AR, Liu YZ. Type I H+-pyrophosphatase regulates the vacuolar storage of sucrose in citrus fruit. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:5935-5947. [PMID: 32589717 DOI: 10.1093/jxb/eraa298] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
The aim of this work was to evaluate the general role of the vacuolar pyrophosphatase proton pump (V-PPase) in sucrose accumulation in citrus species. First, three citrus V-PPase genes, designated CsVPP-1, CsVPP-2, and CsVPP-4, were identified in the citrus genome. CsVPP-1 and CsVPP-2 belonging to citrus type I V-PPase genes are targeted to the tonoplast, and CsVPP-4 belonging to citrus type II V-PPase genes is located in the Golgi bodies. Moreover, there was a significantly positive correlation between transcript levels of type I V-PPase genes and sucrose, rather than hexose, content in fruits of seven citrus cultivars. Drought and abscisic acid treatments significantly induced the CsVPP-1 and CsVPP-2 transcript levels, as well as the sucrose content. The overexpression of type I V-PPase genes significantly increased PPase activity, decreased pyrophosphate contents, and increased sucrose contents, whereas V-PPase inhibition produced the opposite effect in both citrus fruits and leaves. Furthermore, altering the expression levels of type I V-PPase genes significantly influenced the transcript levels of sucrose transporter genes. Taken together, this study demonstrated that CsVPP-1 and CsVPP-2 play key roles in sucrose storage in the vacuole by regulating pyrophosphate homeostasis, ultimately the sucrose biosynthesis and transcript levels of sucrose transport genes, providing a novel lead for engineering or breeding modified taste in citrus and other fruits.
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Affiliation(s)
- Syed Bilal Hussain
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
| | - Cai-Yun Shi
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
| | - Ling-Xia Guo
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
| | - Wei Du
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
| | - Ying-Xing Bai
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
| | - Hafiz Muhammad Kamran
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Yong-Zhong Liu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, PR China
- College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, PR China
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Fukuda M, Mieda M, Sato R, Kinoshita S, Tomoyama T, Ferjani A, Maeshima M, Segami S. Lack of Vacuolar H + -Pyrophosphatase and Cytosolic Pyrophosphatases Causes Fatal Developmental Defects in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2020; 11:655. [PMID: 32528505 PMCID: PMC7266078 DOI: 10.3389/fpls.2020.00655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 04/28/2020] [Indexed: 06/11/2023]
Abstract
The cytosolic level of inorganic pyrophosphate (PPi) is finely regulated, with PPi hydrolyzed primarily by the vacuolar H+-pyrophosphatase (H+-PPase, VHP1/FUGU5/AVP1) and secondarily by five cytosolic soluble pyrophosphatases (sPPases; PPa1-PPa5) in Arabidopsis thaliana. Loss-of-function mutants of H+-PPase (fugu5s) have been reported to show atrophic phenotypes in their rosette leaves when nitrate is the sole nitrogen source in the culture medium. For this phenotype, two questions remain unanswered: why does atrophy depend on physical contact between shoots and the medium, and how does ammonium prevent such atrophy. To understand the mechanism driving this phenotype, we analyzed the growth and phenotypes of mutants on ammonium-free medium in detail. fugu5-1 showed cuticle defects, cell swelling, reduced β-glucan levels, and vein malformation in the leaves, suggesting cell wall weakening and cell lethality. Based on the observation in the double mutants fugu5-1 ppa1 and fugu5-1 ppa4 of more severe atrophy compared to fugu5-1, the nitrogen-dependent phenotype might be linked to PPi metabolism. To elucidate the role of ammonium in this process, we examined the fluctuations of sPPase mRNA levels and the possibility of alternative PPi-removing factors, such as other types of pyrophosphatase. First, we found that both the protein and mRNA levels of sPPases were unaffected by the nitrogen source. Second, to assess the influence of other PPi-removing factors, we examined the phenotypes of triple knockout mutants of H+-PPase and two sPPases on ammonium-containing medium. Both fugu5 ppa1 ppa2 and fugu5 ppa1 ppa4 had nearly lethal embryonic phenotypes, with the survivors showing striking dwarfism and abnormal morphology. Moreover, fugu5 ppa1+/- ppa4 showed severe atrophy at the leaf margins. The other triple mutants, fugu5 ppa1 ppa5 and fugu5 ppa2 ppa4, exhibited death of root hairs and were nearly sterile due to deformed pistils, respectively, even when grown on standard medium. Together, these results suggest that H+-PPase and sPPases act in concert to maintain PPi homeostasis, that the existence of other PPi removers is unlikely, and that ammonium may suppress the production of PPi during nitrogen metabolism rather than stimulating PPi hydrolysis.
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Affiliation(s)
- Mayu Fukuda
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Marika Mieda
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Ryosuke Sato
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Satoru Kinoshita
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Takaaki Tomoyama
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, Tokyo, Japan
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- Graduate School of Bioscience and Biotechnology, Chubu University, Kasugai, Japan
| | - Shoji Segami
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- National Institute for Basic Biology, Okazaki, Japan
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Jiang YT, Tang RJ, Zhang YJ, Xue HW, Ferjani A, Luan S, Lin WH. Two tonoplast proton pumps function in Arabidopsis embryo development. THE NEW PHYTOLOGIST 2020; 225:1606-1617. [PMID: 31569267 DOI: 10.1111/nph.16231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 09/22/2019] [Indexed: 06/10/2023]
Abstract
Two types of tonoplast proton pumps, H+ -pyrophosphatase (V-PPase) and the H+ -ATPase (V-ATPase), establish the proton gradient that powers molecular traffic across the tonoplast thereby facilitating turgor regulation and nutrient homeostasis. However, how proton pumps regulate development remains unclear. In this study, we investigated the function of two types of proton pumps in Arabidopsis embryo development and pattern formation. While disruption of either V-PPase or V-ATPase had no obvious effect on plant embryo development, knocking out both resulted in severe defects in embryo pattern formation from the early stage. While the first division in wild-type zygote was asymmetrical, a nearly symmetrical division occurred in the mutant, followed by abnormal pattern formation at all stages of embryo development. The embryonic defects were accompanied by dramatic differences in vacuole morphology and distribution, as well as disturbed localisation of PIN1. The development of mutant cotyledons and root, and the auxin response of mutant seedlings supported the hypothesis that mutants lacking tonoplast proton pumps were defective in auxin transport and distribution. Taking together, we proposed that two tonoplast proton pumps are required for vacuole morphology and PIN1 localisation, thereby controlling vacuole and auxin-related developmental processes in Arabidopsis embryos and seedlings.
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Affiliation(s)
- Yu-Tong Jiang
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Ren-Jie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
| | - Yan-Jie Zhang
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Hong-Wei Xue
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 200032, Shanghai, China
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, 184-8501, Koganei-shi, Japan
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
| | - Wen-Hui Lin
- School of Life Sciences and Biotechnology, The Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, 200240, Shanghai, China
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720, USA
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Tan FQ, Zhang M, Xie KD, Fan YJ, Song X, Wang R, Wu XM, Zhang HY, Guo WW. Polyploidy remodels fruit metabolism by modifying carbon source utilization and metabolic flux in Ponkan mandarin (Citrus reticulata Blanco). PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 289:110276. [PMID: 31623787 DOI: 10.1016/j.plantsci.2019.110276] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 09/13/2019] [Accepted: 09/15/2019] [Indexed: 05/14/2023]
Abstract
The phenotypic variations that follow polyploidization are expected to improve agricultural productivity and efficiency [1]. However, the effect of polyploidization on plant metabolism has rarely been studied. This study evaluated the metabolic alterations that followed autotetraploidization in the fruit of Ponkan mandarin (C. reticulata Blanco) for three consecutive years and explored the underlying changes to the transcriptome. The autotetraploid (4x) Ponkan fruit had higher levels of total acids, ascorbic acid and total phenolic compounds than the diploid (2x). The primary metabolites especially the organic acids tended to accumulate at higher levels in the 4x fruit. Conversely, two major groups of secondary metabolites (i.e. flavonoids and carotenoids) tended to accumulate at lower levels. The expression levels of citric acid biosynthesis-related genes were unaltered in 4x fruit compared to the 2x fruit. Additionally, genes associated with the transport and utilization of citric acid were significantly down-regulated during ripening, which might induce increases in the levels of citric acid in the 4x fruit. Lower levels of flavonoids and carotenoids in the 4x fruit are potentially associated with decreases in the transport and utilization of citric acid, which is an important metabolite. Citric acid contributes to respiration by serving as an intermediated in the tricarboxylic acid cycle (TCA) and also provides carbon for the production of secondary metabolites. This study demonstrates that polyploidization can influence metabolism in plants.
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Affiliation(s)
- Feng-Quan Tan
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Miao Zhang
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Kai-Dong Xie
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Yan-Jie Fan
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Xin Song
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Rong Wang
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiao-Meng Wu
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Hong-Yan Zhang
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China
| | - Wen-Wu Guo
- Key Laboratory of Horticultural Plant Biology (Ministry of Education), College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, China.
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14
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Kuang L, Chen S, Guo Y, Ma H. Quantitative Proteome Analysis Reveals Changes in the Protein Landscape During Grape Berry Development With a Focus on Vacuolar Transport Proteins. FRONTIERS IN PLANT SCIENCE 2019; 10:641. [PMID: 31156689 PMCID: PMC6530609 DOI: 10.3389/fpls.2019.00641] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/29/2019] [Indexed: 05/08/2023]
Abstract
The vacuole plays a central role in fruit growth and quality formation, yet its proteomic landscape is largely unknown. In the present study, a protocol for isolating intact vacuoles from grape flesh tissue was successfully established. Quantitative proteome analysis identified 2533 proteins from five sampling dates along Cabernet Sauvignon berry development from stage I to III; among them, 1443 proteins were identified on all five sampling dates in at least two biological replicates per sample and were designated core proteome, and 1820 were recruited as differentially abundant proteins (DAPs) by sequential pairwise comparisons using arbitrary fold change of >1.5 and P < 0.05. Metabolism consistently constituted the largest category of identified proteins for both core proteome and DAPs, together with a consistently high proportion of protein-fate category proteins, indicating that the classic lytic functions of vegetative cell vacuoles are maintained throughout berry development; accumulation of metabolites involved in high sugar and other berry qualities in the late developmental stage added to the conventional lytic role of the flesh cell vacuoles. Overall increases in abundance of the DAPs were seen in the transporter proteins, membrane fusion/vesicle trafficking, and protein-fate categories, and decreased abundance was seen for DAPs in the stress, energy and cytoskeleton categories as berry development progressed. A very pronounced proteomic change was revealed between late stage I and mid stage II, with 915 increased and 114 decreased DAPs, demonstrating a significant surge of the vacuolar proteome underlying the rather static phenotypical and physiological phase. We identified 161 transport proteins with differential abundance, including proton pumps, aquaporins, sugar transporters, ATP-binding cassette transporters and ion transport proteins, together with organic compound transport proteins, the highest number and variety of berry tonoplast transporters found in grape proteome efforts to date. We further found a pre-positive increment of 96 transport proteins from the middle of stage II, before the berry undergoes its dramatic physiological changes at and following véraison. Our results are the first to describe the proteome of a vacuole-enriched preparation, toward understanding the functions of the largest compartment in berry cells during grape growth and ripening.
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Affiliation(s)
- Liuqing Kuang
- Department of Fruit Tree Sciences, College of Horticulture, China Agricultural University, Beijing, China
| | - Shangwu Chen
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Yan Guo
- College of Biological Sciences, China Agricultural University, Beijing, China
| | - Huiqin Ma
- Department of Fruit Tree Sciences, College of Horticulture, China Agricultural University, Beijing, China
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15
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Sahitya UL, Krishna MSR, Suneetha P. Integrated approaches to study the drought tolerance mechanism in hot pepper ( Capsicum annuum L.). PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2019; 25:637-647. [PMID: 31168229 PMCID: PMC6522565 DOI: 10.1007/s12298-019-00655-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/20/2019] [Accepted: 03/13/2019] [Indexed: 05/13/2023]
Abstract
Drought is one of the predominant abiotic stresses which have phenomenal impact on crop productivity. Alterations in aquaporin gene expressions are part of complex molecular responses by plant in response to drought. To better understand the role of aquaporins in economically important crop chilli (Capsicum annuum), drought induced gene expression of twelve aquaporins was determined in drought tolerant-KCa-4884 and drought susceptible-G-4 genotypes. Conjointly, the effect of drought on leaf water status and photosynthetic parameters were evaluated. Gene expression of all examined 12 aquaporins was up-regulated in KCa-4884 and in contrast, all the aquaporin genes were down-regulated in G-4 under drought stress. Significant variations among two chilli genotypes have been recorded in photosynthetic rate (P n ), stomatal conductance (G s ), and relative water content (RWC), sub-stomatal CO2 concentration (C i ). KCa-4884 revealed significantly high rates of P n and RWC and decreased G s under water deficit conditions providing evidence for superior drought adaptive strategies. Differences in physiological parameters illustrate prevention of water loss during drought. Up-regulation of aquaporins in drought tolerant genotype implicates their possible role in water relations and photosynthetic performance even under extended drought conditions.
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Affiliation(s)
- U. Lakshmi Sahitya
- Department of Biotechnology, KLEF Deemed to be University, Guntur, Andhra Pradesh India
| | - M. S. R. Krishna
- Department of Biotechnology, KLEF Deemed to be University, Guntur, Andhra Pradesh India
| | - P. Suneetha
- Institute of Biotechnology, Professor Jaya Shankar Telangana State Agricultural University, Hyderabad, Telangana India
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16
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Asaoka M, Inoue SI, Gunji S, Kinoshita T, Maeshima M, Tsukaya H, Ferjani A. Excess Pyrophosphate within Guard Cells Delays Stomatal Closure. PLANT & CELL PHYSIOLOGY 2019; 60:875-887. [PMID: 30649470 DOI: 10.1093/pcp/pcz002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 12/28/2018] [Indexed: 05/08/2023]
Abstract
A variety of cellular metabolic reactions generate inorganic pyrophosphate (PPi) as an ATP hydrolysis byproduct. The vacuolar H+-translocating pyrophosphatase (H+-PPase) loss-of-function fugu5 mutant is susceptible to drought and displays pleotropic postgerminative growth defects due to excess PPi. It was recently reported that stomatal closure after abscisic acid (ABA) treatment is delayed in vhp1-1, a fugu5 allele. In contrast, we found that specific removal of PPi rescued all of the above fugu5 developmental and growth defects. Hence, we speculated that excess PPi itself, rather than vacuolar acidification, might delay stomatal closure. To test this hypothesis, we constructed transgenic plants expressing the yeast IPP1 gene (encoding a cytosolic pyrophosphatase) driven by a guard cell-specific promoter (pGC1::IPP1) in the fugu5 background. Our measurements confirmed stomatal closure defects in fugu5, further supporting a role for H+-PPase in stomatal functioning. Importantly, while pGC1::IPP1 transgenics morphologically mimicked fugu5, stomatal closure was restored in response to ABA and darkness. Quantification of water loss revealed that fugu5 stomata were almost completely insensitive to ABA. In addition, growth of pGC1::IPP1 plants was promoted compared to fugu5 throughout their life; however, it did not reach the wild type level. fugu5 also displayed an increased stomatal index, in violation of the one-cell-spacing rule, and phenotypes recovered upon removal of PPi by pAVP1::IPP1 (FUGU5, VHP1 and AVP1 are the same gene encoding H+-PPase), but not in the pGC1::IPP1 line. Taken together, these results clearly support our hypothesis that dysfunction in stomata is triggered by excess PPi within guard cells, probably via perturbed guard cell metabolism.
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Affiliation(s)
- Mariko Asaoka
- Department of Biology, Tokyo Gakugei University, Koganei-shi, Tokyo, Japan
| | - Shin-Ichiro Inoue
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Shizuka Gunji
- United Graduated School of Education, Tokyo Gakugei University, Tokyo, Japan
| | - Toshinori Kinoshita
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Japan
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Hirokazu Tsukaya
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), Okazaki, Aichi, Japan
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, Koganei-shi, Tokyo, Japan
- United Graduated School of Education, Tokyo Gakugei University, Tokyo, Japan
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Regulatory Aspects of the Vacuolar CAT2 Arginine Transporter of S. lycopersicum: Role of Osmotic Pressure and Cations. Int J Mol Sci 2019; 20:ijms20040906. [PMID: 30791488 PMCID: PMC6413183 DOI: 10.3390/ijms20040906] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 02/11/2019] [Accepted: 02/15/2019] [Indexed: 12/22/2022] Open
Abstract
Many proteins are localized at the vacuolar membrane, but most of them are still poorly described, due to the inaccessibility of this membrane from the extracellular environment. This work focused on the characterization of the CAT2 transporter from S. lycopersicum (SlCAT2) that was previously overexpressed in E. coli and reconstituted in proteoliposomes for transport assay as [3H]Arg uptake. The orientation of the reconstituted transporter has been attempted and current data support the hypothesis that the protein is inserted in the liposome in the same orientation as in the vacuole. SlCAT2 activity was dependent on the pH, with an optimum at pH 7.5. SlCAT2 transport activity was stimulated by the increase of internal osmolality from 0 to 175 mOsmol while the activity was inhibited by the increase of external osmolality. K+, Na+, and Mg2+ present on the external side of proteoliposomes at physiological concentrations, inhibited the transport activity; differently, the cations had no effect when included in the internal proteoliposome compartment. This data highlighted an asymmetric regulation of SlCAT2. Cholesteryl hemisuccinate, included in the proteoliposomal membrane, stimulated the SlCAT2 transport activity. The homology model of the protein was built using, as a template, the 3D structure of the amino acid transporter GkApcT. Putative substrate binding residues and cholesterol binding domains were proposed. Altogether, the described results open new perspectives for studying the response of SlCAT2 and, in general, of plant vacuolar transporters to metabolic and environmental changes.
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18
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Vacuolar Proton Pyrophosphatase Is Required for High Magnesium Tolerance in Arabidopsis. Int J Mol Sci 2018; 19:ijms19113617. [PMID: 30453498 PMCID: PMC6274811 DOI: 10.3390/ijms19113617] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/11/2018] [Accepted: 11/11/2018] [Indexed: 11/17/2022] Open
Abstract
Magnesium (Mg2+) is an essential nutrient in all organisms. However, high levels of Mg2+ in the environment are toxic to plants. In this study, we identified the vacuolar-type H⁺-pyrophosphatase, AVP1, as a critical enzyme for optimal plant growth under high-Mg conditions. The Arabidopsis avp1 mutants displayed severe growth retardation, as compared to the wild-type plants upon excessive Mg2+. Unexpectedly, the avp1 mutant plants retained similar Mg content to wild-type plants under either normal or high Mg conditions, suggesting that AVP1 may not directly contribute to Mg2+ homeostasis in plant cells. Further analyses confirmed that the avp1 mutant plants contained a higher pyrophosphate (PPi) content than wild type, coupled with impaired vacuolar H⁺-pyrophosphatase activity. Interestingly, expression of the Saccharomyces cerevisiae cytosolic inorganic pyrophosphatase1 gene IPP1, which facilitates PPi hydrolysis but not proton translocation into vacuole, rescued the growth defects of avp1 mutants under high-Mg conditions. These results provide evidence that high-Mg sensitivity in avp1 mutants possibly resulted from elevated level of cytosolic PPi. Moreover, genetic analysis indicated that mutation of AVP1 was additive to the defects in mgt6 and cbl2 cbl3 mutants that are previously known to be impaired in Mg2+ homeostasis. Taken together, our results suggest AVP1 is required for cellular PPi homeostasis that in turn contributes to high-Mg tolerance in plant cells.
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19
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Hatakeyama Y, Masumoto-Kubo C, Nonami H, Morita S, Hiraoka K, Onda Y, Nakashima T, Nakano H, Wada H. Evidence for preservation of vacuolar compartments during foehn-induced chalky ring formation of Oryza sativa L. PLANTA 2018; 248:1263-1275. [PMID: 30099651 PMCID: PMC6182326 DOI: 10.1007/s00425-018-2975-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/04/2018] [Indexed: 05/05/2023]
Abstract
Vacuolar compartments being sustained among the amyloplasts inadequately accumulated in rice endosperm cells are the main cause of chalky ring formation under dry wind conditions. Foehn-induced dry wind during the grain-filling stage induces shoot water deficit in rice (Oryza sativa L.) plants, which form a ring-shaped chalkiness in their endosperm that degrades milling quality and rice appearance. Air spaces formed in several inner cells cause significant transparency loss due to irregular light reflection. Although starch synthesis was suggested to be retarded by osmotic adjustment at foehn-induced moderately low water potential, the source of these air spaces remains unknown. We hypothesised that the preservation of vacuoles accompanied by a temporary reduction in starch biosynthesis in the inner cells leads to the chalky ring formation. Panicle water status measurement, light and transmission electron microscopic (TEM) observations, and an absolute qPCR analysis were conducted. Most starch synthesis-related genes exhibited temporarily reduced expression in the inner zone in accordance with the decrease in panicle water status. TEM observations provided evidence that vacuolar compartments remained among the loosely packed starch granules in the inner endosperm cells, where a chalky ring appeared after kernel dehydration. Taken together, we propose that vacuolar compartments sustained among the amyloplasts inadequately accumulated in rice endosperm cells and caused air space formation that leads to ring-shaped chalkiness under dry wind conditions.
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Affiliation(s)
- Yuto Hatakeyama
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization, Chikugo, 833-0041, Japan
| | - Chisato Masumoto-Kubo
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization, Chikugo, 833-0041, Japan
| | - Hiroshi Nonami
- Graduate School of Agriculture, Ehime University, Matsuyama, 790-8566, Japan
| | - Satoshi Morita
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization, Chikugo, 833-0041, Japan
| | - Kenzo Hiraoka
- Clean Energy Research Center, The University of Yamanashi, Kofu, 400-8511, Japan
| | - Yayoi Onda
- Graduate School of Agriculture, Ehime University, Matsuyama, 790-8566, Japan
| | - Taiken Nakashima
- Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Hiroshi Nakano
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization, Chikugo, 833-0041, Japan
| | - Hiroshi Wada
- Kyushu Okinawa Agricultural Research Center, National Agriculture and Food Research Organization, Chikugo, 833-0041, Japan.
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20
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Vigani G, Rolli E, Marasco R, Dell'Orto M, Michoud G, Soussi A, Raddadi N, Borin S, Sorlini C, Zocchi G, Daffonchio D. Root bacterial endophytes confer drought resistance and enhance expression and activity of a vacuolar H + -pumping pyrophosphatase in pepper plants. Environ Microbiol 2018; 21:3212-3228. [PMID: 29786171 DOI: 10.1111/1462-2920.14272] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/03/2018] [Accepted: 05/07/2018] [Indexed: 11/29/2022]
Abstract
It has been previously shown that the transgenic overexpression of the plant root vacuolar proton pumps H+ -ATPase (V-ATPase) and H+ -PPase (V-PPase) confer tolerance to drought. Since plant-root endophytic bacteria can also promote drought tolerance, we hypothesize that such promotion can be associated to the enhancement of the host vacuolar proton pumps expression and activity. To test this hypothesis, we selected two endophytic bacteria endowed with an array of in vitro plant growth promoting traits. Their genome sequences confirmed the presence of traits previously shown to confer drought resistance to plants, such as the synthesis of nitric oxide and of organic volatile organic compounds. We used the two strains on pepper (Capsicuum annuum L.) because of its high sensitivity to drought. Under drought conditions, both strains stimulated a larger root system and enhanced the leaves' photosynthetic activity. By testing the expression and activity of the vacuolar proton pumps, H+ -ATPase (V-ATPase) and H+ -PPase (V-PPase), we found that bacterial colonization enhanced V-PPase only. We conclude that the enhanced expression and activity of V-PPase can be favoured by the colonization of drought-tolerance-inducing bacterial endophytes.
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Affiliation(s)
- Gianpiero Vigani
- Department of Life Sciences and Systems Biology, University of Turin, Plant Physiology Unit, 10135, Turin, Italy
| | - Eleonora Rolli
- Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, 20133, Milan, Italy
| | - Ramona Marasco
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Marta Dell'Orto
- Department of Agricultural and Environmental Sciences, Production, Landscape, Agroenergy (DISAA), University of Milan, 20133, Milan, Italy
| | - Grégoire Michoud
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Asma Soussi
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Noura Raddadi
- Department of Civil, Alma Mater Studiorum University of Bologna, Chemical, Environmental and Materials Engineering (DICAM), Bologna, Italy
| | - Sara Borin
- Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, 20133, Milan, Italy
| | - Claudia Sorlini
- Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, 20133, Milan, Italy
| | - Graziano Zocchi
- Department of Agricultural and Environmental Sciences, Production, Landscape, Agroenergy (DISAA), University of Milan, 20133, Milan, Italy
| | - Daniele Daffonchio
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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21
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Nagy M, Kéki S, Rácz D, Mathur J, Vereb G, Garda T, M-Hamvas M, Chaumont F, Bóka K, Böddi B, Freytag C, Vasas G, Máthé C. Novel fluorochromes label tonoplast in living plant cells and reveal changes in vacuolar organization after treatment with protein phosphatase inhibitors. PROTOPLASMA 2018; 255:829-839. [PMID: 29230547 DOI: 10.1007/s00709-017-1190-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 11/27/2017] [Indexed: 06/07/2023]
Abstract
The recently synthesized isocyanonaphtalene derivatives ACAIN and CACAIN are fluorochromes excitable at wavelengths of around 366 nm and bind cysteine-rich proteins with hydrophobic motifs. We show that these compounds preferentially label tonoplasts in living Arabidopsis and tobacco (Nicotiana tabacum SR1) cells. ACAIN-labeled membranes co-localized with the GFP signal in plants expressing GFP-δ-TIP (TIP2;1) (a tonoplast aquaporin) fusion protein. ACAIN preserved the dynamics of vacuolar structures. tip2;1 and triple tip1;1-tip1;2-tip2;1 knockout mutants showed weaker ACAIN signal in tonoplasts. The fluorochrome is also suitable for the labeling and detection of specific (cysteine-rich, hydrophobic) proteins from crude cell protein extracts following SDS-PAGE and TIP mutants show altered labeling patterns; however, it appears that ACAIN labels a large variety of tonoplast proteins. ACAIN/CACAIN could be used for the detection of altered vacuolar organization induced by the heptapeptide natural toxin microcystin-LR (MCY-LR), a potent inhibitor of both type 1 and 2A protein phosphatases and a ROS inducer. As revealed both in plants with GFP-TIP2;1 fusions and in wild-type (Columbia) plants labeled with ACAIN/CACAIN, MCY-LR induces the formation of small vesicles, concomitantly with the absence of the large vegetative vacuoles characteristic for differentiated cells. TEM studies of MCY-LR-treated Arabidopsis cells proved the presence of multimembrane vesicles, with characteristics of lytic vacuoles or autophagosomes. Moreover, MCY-LR is a stronger inducer of small vesicle formation than okadaic acid (which inhibits preferentially PP2A) and tautomycin (which inhibits preferentially PP1). ACAIN and CACAIN emerge as useful novel tools to study plant vacuole biogenesis and programmed cell death.
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Affiliation(s)
- Miklós Nagy
- Faculty of Science and Technology, Department of Applied Chemistry, University of Debrecen, Egyetem tér 1, Debrecen, H-4032, Hungary
| | - Sándor Kéki
- Faculty of Science and Technology, Department of Applied Chemistry, University of Debrecen, Egyetem tér 1, Debrecen, H-4032, Hungary
| | - Dávid Rácz
- Faculty of Science and Technology, Department of Applied Chemistry, University of Debrecen, Egyetem tér 1, Debrecen, H-4032, Hungary
| | - Jaideep Mathur
- Department of Molecular and Cellular Biology, Laboratory of Plant Development and Interactions, University of Guelph, 50 Stone Road, Guelph, ON, N1G2W1, Canada
| | - György Vereb
- Faculty of Medicine, Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, Hungary
| | - Tamás Garda
- Faculty of Science and Technology, Department of Botany, University of Debrecen, Debrecen, Hungary
| | - Márta M-Hamvas
- Faculty of Science and Technology, Department of Botany, University of Debrecen, Debrecen, Hungary
| | - François Chaumont
- Institut des Sciences de la Vie, Université catholique de Louvain, B-1348, Louvain-la-Neuve, Belgium
| | - Károly Bóka
- ELTE Eötvös Loránd University, Department of Plant Anatomy, Institute of Biology, Faculty of Science, Pázmány P. s. 1/c, Budapest, H-1117, Hungary
| | - Béla Böddi
- ELTE Eötvös Loránd University, Department of Plant Anatomy, Institute of Biology, Faculty of Science, Pázmány P. s. 1/c, Budapest, H-1117, Hungary
| | - Csongor Freytag
- Faculty of Science and Technology, Department of Botany, University of Debrecen, Debrecen, Hungary
| | - Gábor Vasas
- Faculty of Science and Technology, Department of Botany, University of Debrecen, Debrecen, Hungary
| | - Csaba Máthé
- Faculty of Science and Technology, Department of Botany, University of Debrecen, Debrecen, Hungary.
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22
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Zhao C, Haigh AM, Holford P, Chen ZH. Roles of Chloroplast Retrograde Signals and Ion Transport in Plant Drought Tolerance. Int J Mol Sci 2018; 19:E963. [PMID: 29570668 PMCID: PMC5979362 DOI: 10.3390/ijms19040963] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/18/2018] [Accepted: 03/20/2018] [Indexed: 01/09/2023] Open
Abstract
Worldwide, drought affects crop yields; therefore, understanding plants' strategies to adapt to drought is critical. Chloroplasts are key regulators of plant responses, and signals from chloroplasts also regulate nuclear gene expression during drought. However, the interactions between chloroplast-initiated retrograde signals and ion channels under stress are still not clear. In this review, we summarise the retrograde signals that participate in regulating plant stress tolerance. We compare chloroplastic transporters that modulate retrograde signalling through retrograde biosynthesis or as critical components in retrograde signalling. We also discuss the roles of important plasma membrane and tonoplast ion transporters that are involved in regulating stomatal movement. We propose how retrograde signals interact with ion transporters under stress.
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Affiliation(s)
- Chenchen Zhao
- School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia.
| | - Anthony M Haigh
- School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia.
| | - Paul Holford
- School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia.
| | - Zhong-Hua Chen
- School of Science and Health, Western Sydney University, Penrith, NSW 2751, Australia.
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia.
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23
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Hsu YD, Huang YF, Pan YJ, Huang LK, Liao YY, Lin WH, Liu TY, Lee CH, Pan RL. Regulation of H +-pyrophosphatase by 14-3-3 Proteins from Arabidopsis thaliana. J Membr Biol 2018; 251:263-276. [PMID: 29453559 DOI: 10.1007/s00232-018-0020-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 02/10/2018] [Indexed: 12/29/2022]
Abstract
Plant vacuolar H+-transporting inorganic pyrophosphatase (V-PPase; EC 3.6.1.1) is a crucial enzyme that exists on the tonoplast to maintain pH homeostasis across the vacuolar membrane. This enzyme generates proton gradient between cytosol and vacuolar lumen by hydrolysis of a metabolic byproduct, pyrophosphate (PP i ). The regulation of V-PPase at protein level has drawn attentions of many workers for decades, but its mechanism is still unclear. In this work, we show that AVP1, the V-PPase from Arabidopsis thaliana, is a target protein for regulatory 14-3-3 proteins at the vacuolar membrane, and all twelve 14-3-3 isoforms were analyzed for their association with AVP1. In the presence of 14-3-3ν, -µ, -ο, and -ι, both enzymatic activities and its associated proton pumping of AVP1 were increased. Among these 14-3-3 proteins, 14-3-3 µ shows the highest stimulation on coupling efficiency. Furthermore, 14-3-3ν, -µ, -ο, and -ι exerted protection of AVP1 against the inhibition of suicidal substrate PP i at high concentration. Moreover, the thermal profile revealed the presence of 14-3-3ο improves the structural stability of AVP1 against high temperature deterioration. Additionally, the 14-3-3 proteins mitigate the inhibition of Na+ to AVP1. Besides, the binding sites/motifs of AVP1 were identified for each 14-3-3 protein. Taken together, a working model was proposed to elucidate the association of 14-3-3 proteins with AVP1 for stimulation of its enzymatic activity.
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Affiliation(s)
- Yu-Di Hsu
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Yu-Fen Huang
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Yih-Jiuan Pan
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Li-Kun Huang
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Ya-Yun Liao
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Wei-Hua Lin
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Tzu-Yin Liu
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China
| | - Ching-Hung Lee
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China.
| | - Rong-Long Pan
- Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsin Chu, 30013, Taiwan, Republic of China.
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Meng L, Li S, Guo J, Guo Q, Mao P, Tian X. Molecular cloning and functional characterisation of an H +-pyrophosphatase from Iris lactea. Sci Rep 2017; 7:17779. [PMID: 29259318 PMCID: PMC5736642 DOI: 10.1038/s41598-017-18032-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 12/05/2017] [Indexed: 11/18/2022] Open
Abstract
Tonoplast H+-pyrophosphatases (VPs) mediate vacuolar Na+ sequestration, a process important for salt tolerance of plants. The function of VP in the highly drought- and salt-tolerant perennial Iris lactea under salt stress is unclear. Here, we isolated IlVP from I. lactea and investigated its function in transgenic tobacco. IlVP was found to comprise 771 amino acid residues and showed 88% similarity with Arabidopsis AtVP1. IlVP was mainly expressed in shoots and was up-regulated by salt stress. Overexpression of IlVP enhanced growth of transgenic tobacco plants compared with wild-type (WT) plants exposed to salt stress. Transgenic plants accumulated higher quantities of Na+ and K+ in leaves, stems, and roots under salt stress, which caused higher leaf relative water content and decreased cell membrane damage compared with WT plants. Overall, IlVP encoding a tonoplast H+-pyrophosphatase can reduce Na+ toxicity in plant cells through increased sequestration of ions into vacuoles by enhanced H+-pyrophosphatase activity.
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Affiliation(s)
- Lin Meng
- Beijing Research and Development Center for Grass and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, P. R. China.
| | - Shanshan Li
- Beijing Research and Development Center for Grass and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, P. R. China
| | - Jingya Guo
- Beijing Research and Development Center for Grass and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, P. R. China
| | - Qiang Guo
- Beijing Research and Development Center for Grass and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, P. R. China
| | - Peichun Mao
- Beijing Research and Development Center for Grass and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, P. R. China
| | - Xiaoxia Tian
- Beijing Research and Development Center for Grass and Environment, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, P. R. China
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Are Aquaporins (AQPs) the Gateway that Conduits Nutrients, Persistent Organic Pollutants and Perfluoroalkyl Substances (PFASs) into Plants? ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s40362-017-0045-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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26
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Thirugnanasambandam PP, Hoang NV, Furtado A, Botha FC, Henry RJ. Association of variation in the sugarcane transcriptome with sugar content. BMC Genomics 2017; 18:909. [PMID: 29178834 PMCID: PMC5702190 DOI: 10.1186/s12864-017-4302-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 11/14/2017] [Indexed: 01/01/2023] Open
Abstract
Background Sugarcane is a major crop of the tropics cultivated mainly for its high sucrose content. The crop is genetically less explored due to its complex polyploid genome. Sucrose synthesis and accumulation are complex processes influenced by physiological, biochemical and genetic factors, and the growth environment. The recent focus on the crop for fibre and biofuel has led to a renewed interest on understanding the molecular basis of sucrose and biomass traits. This transcriptome study aimed to identify genes that are associated with and differentially regulated during sucrose synthesis and accumulation in the mature stage of sugarcane. Patterns of gene expression in high and low sugar genotypes as well as mature and immature culm tissues were studied using RNA-Seq of culm transcriptomes. Results In this study, 28 RNA-Seq libraries from 14 genotypes of sugarcane differing in their sucrose content were used for studying the transcriptional basis of sucrose accumulation. Differential gene expression studies were performed using SoGI (Saccharum officinarum Gene Index, 3.0), SAS (sugarcane assembled sequences) of sugarcane EST database (SUCEST) and SUGIT, a sugarcane Iso-Seq transcriptome database. In total, about 34,476 genes were found to be differentially expressed between high and low sugar genotypes with the SoGI database, 20,487 genes with the SAS database and 18,543 genes with the SUGIT database at FDR < 0.01, using the Baggerley’s test. Further, differential gene expression analyses were conducted between immature (top) and mature (bottom) tissues of the culm. The DEGs were functionally annotated using GO classification and the genes consistently associated with sucrose accumulation were identified. Conclusions The large number of DEGs may be due to the large number of genes that influence sucrose content or are regulated by sucrose content. These results indicate that apart from being a primary metabolite and storage and transport sugar, sucrose may serve as a signalling molecule that regulates many aspects of growth and development in sugarcane. Further studies are needed to confirm if sucrose regulates the expression of the identified DEGs or vice versa. The DEGs identified in this study may lead to identification of genes/pathways regulating sucrose accumulation and/or regulated by sucrose levels in sugarcane. We propose identifying the master regulators of sucrose if any in the future. Electronic supplementary material The online version of this article (10.1186/s12864-017-4302-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Prathima P Thirugnanasambandam
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, 4072, Australia.,ICAR - Sugarcane Breeding Institute, Coimbatore, Tamil Nadu, India
| | - Nam V Hoang
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, 4072, Australia.,College of Agriculture and Forestry, Hue University, Hue, Vietnam
| | - Agnelo Furtado
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | | | - Robert J Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, 4072, Australia. .,The University of Queensland, Room 2.245, Level 2, The John Hay Building, Queensland Biosciences Precinct [#80], 306 Carmody Road, St Lucia, QLD, 4072, Australia.
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Tonoplast-localized nitrate uptake transporters involved in vacuolar nitrate efflux and reallocation in Arabidopsis. Sci Rep 2017; 7:6417. [PMID: 28743909 PMCID: PMC5526873 DOI: 10.1038/s41598-017-06744-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 06/16/2017] [Indexed: 11/17/2022] Open
Abstract
A great proportion of nitrate taken up by plants is stored in vacuoles. Vacuolar nitrate accumulation and release is of great importance to nitrate reallocation and efficient utilization. However, how plants mediate nitrate efflux from vacuoles to cytoplasm is largely unknown. The current study identified NPF5.11, NPF5.12 and NPF5.16 as vacuolar nitrate efflux transporters in Arabidopsis. Histochemical analysis showed that NPF5.11, NPF5.12 and NPF5.16 were expressed preferentially in root pericycle cells and xylem parenchyma cells, and further analysis showed that these proteins were tonoplast-localized. Functional characterization using cRNA-injected Xenopus laevis oocytes showed that NPF5.11, NPF5.12 and NPF5.16 were low-affinity, pH-dependent nitrate uptake transporters. In npf5.11 npf5.12 npf5.16 triple mutant lines, more root-fed 15NO3− was translocated to shoots compared to the wild type control. In the NPF5.12 overexpression lines, proportionally less nitrate was maintained in roots. These data together suggested that NPF5.11, NPF5.12 and NPF5.16 might function to uptake nitrate from vacuoles into cytosol, thus serving as important players to modulate nitrate allocation between roots and shoots.
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Huang X, Yang L, Jin Y, Lin J, Liu F. Generation, Annotation, and Analysis of a Large-Scale Expressed Sequence Tag Library from Arabidopsis pumila to Explore Salt-Responsive Genes. FRONTIERS IN PLANT SCIENCE 2017; 8:955. [PMID: 28638397 PMCID: PMC5461257 DOI: 10.3389/fpls.2017.00955] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 05/22/2017] [Indexed: 06/29/2023]
Abstract
Arabidopsis pumila is an ephemeral plant, and a close relative of the model plant Arabidopsis thaliana, but it possesses higher photosynthetic efficiency, higher propagation rate, and higher salinity tolerance compared to those A. thaliana, thus providing a candidate plant system for gene mining for environmental adaption and salt tolerance. However, A. pumila is an under-explored resource for understanding the genetic mechanisms underlying abiotic stress adaptation. To improve our understanding of the molecular and genetic mechanisms of salt stress adaptation, more than 19,900 clones randomly selected from a cDNA library constructed previously from leaf tissue exposed to high-salinity shock were sequenced. A total of 16,014 high-quality expressed sequence tags (ESTs) were generated, which have been deposited in the dbEST GenBank under accession numbers JZ932319 to JZ948332. Clustering and assembly of these ESTs resulted in the identification of 8,835 unique sequences, consisting of 2,469 contigs and 6,366 singletons. The blastx results revealed 8,011 unigenes with significant similarity to known genes, while only 425 unigenes remained uncharacterized. Functional classification demonstrated an abundance of unigenes involved in binding, catalytic, structural or transporter activities, and in pathways of energy, carbohydrate, amino acid, or lipid metabolism. At least seven main classes of genes were related to salt-tolerance among the 8,835 unigenes. Many previously reported salt tolerance genes were also manifested in this library, for example VP1, H+-ATPase, NHX1, SOS2, SOS3, NAC, MYB, ERF, LEA, P5CS1. In addition, 251 transcription factors were identified from the library, classified into 42 families. Lastly, changes in expression of the 12 most abundant unigenes, 12 transcription factor genes, and 19 stress-related genes in the first 24 h of exposure to high-salinity stress conditions were monitored by qRT-PCR. The large-scale EST library obtained in this study provides first-hand information on gene sequences expressed in young leaves of A. pumila exposed to salt shock. The rapid discovery of known or unknown genes related to salinity stress response in A. pumila will facilitate the understanding of complex adaptive mechanisms for ephemerals.
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29
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Lv X, Jing Y, Wu H, Lin J. Tracking Tonoplast Protein Behaviors in Intact Vacuoles Isolated from Arabidopsis Leaves. MOLECULAR PLANT 2017; 10:349-352. [PMID: 27816695 DOI: 10.1016/j.molp.2016.10.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 09/28/2016] [Accepted: 10/26/2016] [Indexed: 06/06/2023]
Affiliation(s)
- Xueqin Lv
- College of Biological Sciences & Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Yanping Jing
- College of Biological Sciences & Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Hongyang Wu
- College of Biological Sciences & Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Jinxing Lin
- College of Biological Sciences & Biotechnology, Beijing Forestry University, Beijing 100083, China.
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Rodrigues MI, Takeda AAS, Bravo JP, Maia IG. The Eucalyptus Tonoplast Intrinsic Protein (TIP) Gene Subfamily: Genomic Organization, Structural Features, and Expression Profiles. FRONTIERS IN PLANT SCIENCE 2016; 7:1810. [PMID: 27965702 PMCID: PMC5127802 DOI: 10.3389/fpls.2016.01810] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
Plant aquaporins are water channels implicated in various physiological processes, including growth, development and adaptation to stress. In this study, the Tonoplast Intrinsic Protein (TIP) gene subfamily of Eucalyptus, an economically important woody species, was investigated and characterized. A genome-wide survey of the Eucalyptus grandis genome revealed the presence of eleven putative TIP genes (referred as EgTIP), which were individually assigned by phylogeny to each of the classical TIP1-5 groups. Homology modeling confirmed the presence of the two highly conserved NPA (Asn-Pro-Ala) motifs in the identified EgTIPs. Residue variations in the corresponding selectivity filters, that might reflect differences in EgTIP substrate specificity, were observed. All EgTIP genes, except EgTIP5.1, were transcribed and the majority of them showed organ/tissue-enriched expression. Inspection of the EgTIP promoters revealed the presence of common cis-regulatory elements implicated in abiotic stress and hormone responses pointing to an involvement of the identified genes in abiotic stress responses. In line with these observations, additional gene expression profiling demonstrated increased expression under polyethylene glycol-imposed osmotic stress. Overall, the results obtained suggest that these novel EgTIPs might be functionally implicated in eucalyptus adaptation to stress.
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Affiliation(s)
- Marcela I. Rodrigues
- Department of Genetics, Institute of Biosciences of Botucatu, São Paulo State UniversityBotucatu, Brazil
| | - Agnes A. S. Takeda
- Department of Physics and Biophysics, Institute of Biosciences of Botucatu, São Paulo State UniversityBotucatu, Brazil
- Institute of Biotechnology, São Paulo State UniversityBotucatu, Brazil
| | - Juliana P. Bravo
- Department of Genetics, Institute of Biosciences of Botucatu, São Paulo State UniversityBotucatu, Brazil
| | - Ivan G. Maia
- Department of Genetics, Institute of Biosciences of Botucatu, São Paulo State UniversityBotucatu, Brazil
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31
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Regmi KC, Pizzio GA, Gaxiola RA. Structural basis for the reversibility of proton pyrophosphatase. PLANT SIGNALING & BEHAVIOR 2016; 11:e1231294. [PMID: 27611445 PMCID: PMC5257167 DOI: 10.1080/15592324.2016.1231294] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Proton Pyrophosphatase (H+-PPase) is an evolutionarily conserved enzyme regarded as a bona fide vacuolar marker. However, H+-PPase also localizes at the plasma membrane of the phloem, where, evidence suggests that it functions as a Pyrophosphate Synthase and participates in phloem loading and photosynthate partitioning. We believe that this pyrophosphate synthesising function of H+-PPase is fundamentally rooted to its molecular structure, and here we postulate, on the basis of published crystal structures of membrane-bound pyrophosphatases, a plausible mechanism of pyrophosphate synthesis.
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Affiliation(s)
- Kamesh C. Regmi
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Gaston A. Pizzio
- Center for Research in Agricultural Genomics, Cerdanyola del Vallès, Barcelona, Spain
| | - Roberto A. Gaxiola
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- CONTACT Roberto A. Gaxiola
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Molecular Characterization of LRB7 Gene and a Water Channel Protein TIP2 in Chorispora bungeana. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2483258. [PMID: 27689074 PMCID: PMC5023841 DOI: 10.1155/2016/2483258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/20/2016] [Indexed: 11/24/2022]
Abstract
Background. Water channel proteins, also called aquaporins, are integral membrane proteins from major intrinsic protein (MIP) family and involved in several pathways including not only water transport but also cell signaling, reproduction, and photosynthesis. The full cDNA and protein sequences of aquaporin in Chorispora bungeana Fisch. & C.A. Mey (C. bungeana) are still unknown. Results. In this study, PCR and rapid amplification of cDNA ends approaches were used to clone the full cDNA of LRB7 (GenBank accession number: EU636988) of C. bungeana. Sequence analysis indicated that it was 1235 bp, which had two introns and encoded a protein of 250 amino acids. Structure analysis revealed that the protein had two conserved NPA motifs, one of which is MIP signature sequence (SGxHxNPAVT), six membrane helix regions, and additional membrane-embedded domains. Phylogenetic analysis suggested that the protein was from TIP2 subgroup. Surprisingly, semiquantitative RT-PCR experiment and western blot analysis showed that LRB7 and TIP2 were only detectable in roots, unlike Arabidopsis and Raphanus. Connecting with our previous studies, LRB7 was supported to associate with chilling-tolerance in C. bungeana. Conclusion. This is the first time to characterize the full sequences of LRB7 gene and water channel protein in C. bungeana. Our findings contribute to understanding the water transports in plants under low temperatures.
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Abstract
Aquaporins of the TIP subfamily (Tonoplast Intrinsic Proteins) have been suggested to facilitate permeation of water and ammonia across the vacuolar membrane of plants, allowing the vacuole to efficiently sequester ammonium ions and counteract cytosolic fluctuations of ammonia. Here, we report the structure determined at 1.18 Å resolution from twinned crystals of Arabidopsis thaliana aquaporin AtTIP2;1 and confirm water and ammonia permeability of the purified protein reconstituted in proteoliposomes as further substantiated by molecular dynamics simulations. The structure of AtTIP2;1 reveals an extended selectivity filter with the conserved arginine of the filter adopting a unique unpredicted position. The relatively wide pore and the polar nature of the selectivity filter clarify the ammonia permeability. By mutational studies, we show that the identified determinants in the extended selectivity filter region are sufficient to convert a strictly water-specific human aquaporin into an AtTIP2;1-like ammonia channel. A flexible histidine and a novel water-filled side pore are speculated to deprotonate ammonium ions, thereby possibly increasing permeation of ammonia. The molecular understanding of how aquaporins facilitate ammonia flux across membranes could potentially be used to modulate ammonia losses over the plasma membrane to the atmosphere, e.g., during photorespiration, and thereby to modify the nitrogen use efficiency of plants. The structure of an ammonia channel from plants extends our understanding of substrate specificity in different types of aquaporins and reveals an intriguing side pore that raises new questions. Ammonia is a central molecule in nitrogen metabolism. Aquaporins are integral membrane proteins that form channels that accelerate the passive permeation of small polar uncharged molecules, like water and ammonia, across lipid membranes of the cell. Structural information of ammonia-permeable aquaporins has been lacking. Here, we report a high-resolution structure of the ammonia-permeable aquaporin AtTIP2;1 and explore it by functional assays of mutants and by molecular dynamics simulations. Our data uncover unexpected features of the substrate selectivity filter, including a conserved arginine in a new orientation that is stabilized by interactions to a histidine that is linked to ammonia specificity. An additional histidine in a different part of AtTIP2;1 fortifies the position of the arginine and interacts directly with the substrate in the channel. This histidine is therefore included in an extended selectivity filter, which should prompt a reinterpretation of the determinants of specificity in all types of aquaporins. We speculate that an intriguing water-filled side pore, next to the substrate-binding histidine, participates in deprotonating ammonium ions, which could increase the net permeation of ammonia. Understanding the principles of ammonia permeability may, in the future, allow us to modulate the passage of ammonia and generate crops with higher nitrogen-use efficiency.
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Reuscher S, Fukao Y, Morimoto R, Otagaki S, Oikawa A, Isuzugawa K, Shiratake K. Quantitative Proteomics-Based Reconstruction and Identification of Metabolic Pathways and Membrane Transport Proteins Related to Sugar Accumulation in Developing Fruits of Pear (Pyrus communis). PLANT & CELL PHYSIOLOGY 2016; 57:505-18. [PMID: 26755692 DOI: 10.1093/pcp/pcw004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/05/2016] [Indexed: 05/09/2023]
Abstract
During their 6 month development, pear (Pyrus communis) fruits undergo drastic changes in their morphology and their chemical composition. To gain a better understanding of the metabolic pathways and transport processes active during fruit development, we performed a time-course analysis using mass spectrometry (MS)-based protein identification and quantification of fruit flesh tissues. After pre-fractionation of the samples, 2,841 proteins were identified. A principal component analysis (PCA) separated the samples from seven developmental stages into three distinct clusters representing the early, mid and late developmental phase. Over-representation analysis of proteins characteristic of each developmental phase revealed both expected and novel biological processes relevant at each phase. A high abundance of aquaporins was detected in samples from fruits in the cell expansion stage. We were able quantitatively to reconstruct basic metabolic pathways such as the tricarboxylic acid (TCA) cycle, which indicates sufficient coverage to reconstruct other metabolic pathways. Most of the enzymes that presumably contribute to sugar accumulation in pear fruits could be identified. Our data indicate that invertases do not play a major role in the sugar conversions in developing pear fruits. Rather, sucrose might be broken down by sucrose synthases. Further focusing on sugar transporters, we identified several putative sugar transporters from diverse families which showed developmental regulation. In conclusion, our data set comprehensively describes the proteome of developing pear fruits and provides novel insights about sugar accumulation as well as candidate genes for key reactions and transport steps.
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Affiliation(s)
- Stefan Reuscher
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
| | - Yoichiro Fukao
- College of Life Sciences, Ritsumeikan University, Kusatsu, 525-8577 Japan
| | - Reina Morimoto
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
| | - Shungo Otagaki
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
| | - Akira Oikawa
- Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555 Japan RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan
| | - Kanji Isuzugawa
- Yamagata Integrated Agricultural Research Center, Sagae, 999-7601 Japan
| | - Katsuhiro Shiratake
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
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Asaoka M, Segami S, Ferjani A, Maeshima M. Contribution of PPi-Hydrolyzing Function of Vacuolar H(+)-Pyrophosphatase in Vegetative Growth of Arabidopsis: Evidenced by Expression of Uncoupling Mutated Enzymes. FRONTIERS IN PLANT SCIENCE 2016; 7:415. [PMID: 27066051 PMCID: PMC4814480 DOI: 10.3389/fpls.2016.00415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 03/17/2016] [Indexed: 05/06/2023]
Abstract
The vacuolar-type H(+)-pyrophosphatase (H(+)-PPase) catalyzes a coupled reaction of pyrophosphate (PPi) hydrolysis and active proton translocation across the tonoplast. Overexpression of H(+)-PPase improves growth in various plant species, and loss-of-function mutants (fugu5s) of H(+)-PPase in Arabidopsis thaliana have post-germinative developmental defects. Here, to further clarify the physiological significance of this important enzyme, we newly generated three varieties of H(+)-PPase overexpressing lines with different levels of activity that we analyzed together with the loss-of-function mutant fugu5-3. The H(+)-PPase overexpressors exhibited enhanced activity of H(+)-PPase during vegetative growth, but no change in the activity of vacuolar H(+)-ATPase. Overexpressors with high enzymatic activity grew more vigorously with fresh weight increased by more than 24 and 44%, compared to the wild type and fugu5-3, respectively. Consistently, the overexpressors had larger rosette leaves and nearly 30% more cells in leaves than the wild type. When uncoupling mutated variants of H(+)-PPase, that could hydrolyze PPi but could not translocate protons, were introduced into the fugu5-3 mutant background, shoot growth defects recovered to the same levels as when a normal H(+)-PPase was introduced. Taken together, our findings clearly demonstrate that additional expression of H(+)-PPase improves plant growth by increasing cell number, predominantly as a consequence of the PPi-hydrolyzing activity of the enzyme.
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Affiliation(s)
- Mariko Asaoka
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
| | - Shoji Segami
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei UniversityTokyo, Japan
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
- *Correspondence: Masayoshi Maeshima,
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Fukuda M, Segami S, Tomoyama T, Asaoka M, Nakanishi Y, Gunji S, Ferjani A, Maeshima M. Lack of H(+)-pyrophosphatase Prompts Developmental Damage in Arabidopsis Leaves on Ammonia-Free Culture Medium. FRONTIERS IN PLANT SCIENCE 2016; 7:819. [PMID: 27375667 PMCID: PMC4901044 DOI: 10.3389/fpls.2016.00819] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 05/25/2016] [Indexed: 05/06/2023]
Abstract
The plant vacuolar H(+)-pyrophosphatase (H(+)-PPase) functions as a proton pump coupled with the hydrolysis of pyrophosphate (PPi). Loss-of-function mutants (fugu5s and vhp1) of the H(+)-PPase of Arabidopsis thaliana show clear morphological phenotypes in the cotyledons, caused by inhibition of gluconeogenesis from seed storage lipids due to excessive accumulation of PPi. In this study, we investigated the phenotypes of the fugu5 and vhp1 mutants during vegetative growth under a specific nitrogen nutritional regime. When nitrate in the culture medium was the sole nitrogen source, growth of the mutant rosette leaves was severely compromised. Interestingly, trypan blue staining revealed notable cell death at the leaf blade-petiole junctions of young leaves, a region known to have meristematic features. Physical contact of the leaf tip with the culture medium also triggered leaf atrophy, suggesting that absorption of some elements through the hydathodes was probably involved in this phenotype. Prevention of such leaf-medium contact resulted in a marked decrease in phosphate content in the shoots, and suppressed leaf atrophy. Furthermore, fugu5 necrotic symptoms were rescued completely by heterologous expression of yeast cytosolic soluble pyrophosphatase IPP1 or uncoupling-type H(+)-PPases that retained only PPi-hydrolysis activity, indicating that the damage of actively proliferating cells was caused by the loss of the PPi-hydrolyzing function of H(+)-PPase. Importantly, cell death and growth defects of the fugu5 leaves were suppressed completely by the simple addition of ammonium (>1 mM) to the culture medium. The PPi content in the shoots of fugu5 grown on ammonium-free medium was 70% higher than that of the wild type, and PPi levels were restored to normal upon growth on ammonium-supplemented medium. Together, these findings suggest that the PPi-hydrolyzing activity of H(+)-PPase is essential to maintain the PPi contents at optimal levels when grown on ammonium-free culture medium, and any direct contact of the leaves with the culture medium may raise PPi levels in the leaves through increased phosphate uptake.
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Affiliation(s)
- Mayu Fukuda
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
| | - Shoji Segami
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
- *Correspondence: Shoji Segami, ; Masayoshi Maeshima,
| | - Takaaki Tomoyama
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
| | - Mariko Asaoka
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
- Department of Biology, Tokyo Gakugei University, KoganeiTokyo, Japan
| | - Yoichi Nakanishi
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
| | - Shizuka Gunji
- Department of Biology, Tokyo Gakugei University, KoganeiTokyo, Japan
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, KoganeiTokyo, Japan
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya UniversityNagoya, Japan
- *Correspondence: Shoji Segami, ; Masayoshi Maeshima,
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Pertl-Obermeyer H, Trentmann O, Duscha K, Neuhaus HE, Schulze WX. Quantitation of Vacuolar Sugar Transporter Abundance Changes Using QconCAT Synthtetic Peptides. FRONTIERS IN PLANT SCIENCE 2016; 7:411. [PMID: 27148277 PMCID: PMC4828444 DOI: 10.3389/fpls.2016.00411] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 03/17/2016] [Indexed: 05/19/2023]
Abstract
Measurements of protein abundance changes are important for biological conclusions on protein-related processes such as activity or complex formation. Proteomic analyses in general are almost routine tasks in many laboratories, but a precise and quantitative description of (absolute) protein abundance changes require careful experimental design and precise data quality. Today, a vast choice of metabolic labeling and label-free quantitation protocols are available, but the trade-off between quantitative precision and proteome coverage of quantified proteins including missing value problems remain. Here, we provide an example of a targeted proteomic approach using artificial standard proteins consisting of concatenated peptides of interest (QconCAT) to specifically quantify abiotic stress-induced abundance changes in low abundant vacuolar transporters. An advantage of this approach is the reliable quantitation of alimited set of low-abundant target proteins throughout different conditions. We show that vacuolar ATPase AVP1 and sugar transporters of the ERDL (early responsive to dehydration-like) family and TMT2 (tonoplast monosaccharide transporter 2) showed increased abundance upon salt stress.
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Affiliation(s)
| | - Oliver Trentmann
- Plant Physiology, University of KaiserslauternKaiserslautern, Germany
| | - Kerstin Duscha
- Plant Physiology, University of KaiserslauternKaiserslautern, Germany
| | | | - Waltraud X. Schulze
- Department of Plant Systems Biology, University of HohenheimStuttgart, Germany
- *Correspondence: Waltraud X. Schulze,
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Hernández A, Serrano-Bueno G, Perez-Castiñeira JR, Serrano A. 8-Dehydrosterols induce membrane traffic and autophagy defects through V-ATPase dysfunction in Saccharomyces cerevisae. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2945-56. [PMID: 26344037 DOI: 10.1016/j.bbamcr.2015.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022]
Abstract
8-Dehydrosterols are present in a wide range of biologically relevant situations, from human rare diseases to amine fungicide-treated fungi and crops. However, the molecular bases of their toxicity are still obscure. We show here that 8-dehydrosterols, but not other sterols, affect yeast vacuole acidification through V-ATPases. Moreover, erg2Δ cells display reductions in proton pumping rates consistent with ion-transport uncoupling in vitro. Concomitantly, subunit Vph1p shows conformational changes in the presence of 8-dehydrosterols. Expression of a plant vacuolar H(+)-pumping pyrophosphatase as an alternative H(+)-pump relieves Vma(-)-like phenotypes in erg2Δ-derived mutant cells. As a consequence of these acidification defects, endo- and exo-cytic traffic deficiencies that can be alleviated with a H(+)-pumping pyrophosphatase are also observed. Despite their effect on membrane traffic, 8-dehydrosterols do not induce endoplasmic reticulum stress or assembly defects on the V-ATPase. Autophagy is a V-ATPase dependent process and erg2Δ mutants accumulate autophagic bodies under nitrogen starvation similar to Vma(-) mutants. In contrast to classical Atg(-) mutants, this defect is not accompanied by impairment of traffic through the CVT pathway, processing of Pho8Δ60p, GFP-Atg8p localisation or difficulties to survive under nitrogen starvation conditions, but it is concomitant to reduced vacuolar protease activity. All in all, erg2Δ cells are autophagy mutants albeit some of their phenotypic features differ from classical Atg(-) defective cells. These results may pave the way to understand the aetiology of sterol-related diseases, the cytotoxic effect of amine fungicides, and may explain the tolerance to these compounds observed in plants.
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Affiliation(s)
- Agustín Hernández
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain.
| | - Gloria Serrano-Bueno
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain
| | - José Román Perez-Castiñeira
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain
| | - Aurelio Serrano
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Avda Américo Vespucio 48, 41092 Sevilla, Spain.
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Lin Q, Li S, Dong W, Feng C, Yin X, Xu C, Sun C, Chen K. Involvement of CitCHX and CitDIC in developmental-related and postharvest-hot-air driven citrate degradation in citrus fruits. PLoS One 2015; 10:e0119410. [PMID: 25738939 PMCID: PMC4349887 DOI: 10.1371/journal.pone.0119410] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 01/13/2015] [Indexed: 01/08/2023] Open
Abstract
Citrate is the predominant organic acid associated with taste in citrus fruit. Although citrate metabolism has been widely studied in recent years, the potential contributions of transport proteins to citrate content remain unclear. In the present study, high-acid citrus fruit Gaocheng ('GC', Citrus sp.) and low-acid citrus fruit Satsuma mandarin ('SM', Citrus unshiu Marc.) were selected for study, and the degradation of citrate was deduced to be the main cause of the difference in acidity in fully mature fruits. RNA-seq analysis was carried out on 'GC' and 'SM' fruit samples over the same time course, and the results indicated that citrate degradation occurred mainly through the glutamine pathway, catalyzed by CitAco3-CitGS2-CitGDU1, and also two transport-related genes, CitCHX and CitDIC, were shown to be associated with citrate degradation. These results were confirmed by real-time PCR. In postharvest 'GC' fruit, the expressions of these two transport-related genes were induced by 2-fold under hot air treatment, accompanied by a reduction of 7%-9% in total acid degradation. Transient expression of CitCHX and CitDIC in tobacco leaves was performed, and the citrate content was reduced by 62%, 75% and 78% following CitCHX, CitDIC and CitCHX plus CitDIC treatments, respectively, as compared with expression of an empty vector. Overall, these data indicated that two transport proteins, CitCHX and CitDIC, are not only involved in citrate degradation during fruit development, but also involved in postharvest hot air triggered citrate reduction.
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Affiliation(s)
- Qiong Lin
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Shaojia Li
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Wencheng Dong
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Chao Feng
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Xueren Yin
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Changjie Xu
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Chongde Sun
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Kunsong Chen
- Laboratory of Fruit Quality Biology, The State Agriculture Ministry Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Zhejiang University, Hangzhou, 310058, P. R. China
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Chen YW, Lee CH, Huang YT, Pan YJ, Lin SM, Lo YY, Lee CH, Huang LK, Huang YF, Hsu YD, Pan RL. Functional and fluorescence analyses of tryptophan residues in H+-pyrophosphatase of Clostridium tetani. J Bioenerg Biomembr 2015; 46:127-34. [PMID: 24121937 DOI: 10.1007/s10863-013-9532-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 10/01/2013] [Indexed: 10/26/2022]
Abstract
Homodimeric proton-translocating pyrophosphatase (H+-PPase; EC 3.6.1.1) maintains the cytoplasmic pH homeostasis of many bacteria and higher plants by coupling pyrophosphate (PPi) hydrolysis and proton translocation. H+-PPase accommodates several essential motifs involved in the catalytic mechanism, including the PPi binding motif and Acidic I and II motifs. In this study, 3 intrinsic tryptophan residues, Trp-75, Trp-365, and Trp-602, in H+-PPase from Clostridium tetani were used as internal probes to monitor the local conformational state of the periplasm domain, transmembrane region, and cytoplasmic domain, respectively. Upon binding of the substrate analog Mg-imidodiphosphate (Mg-IDP), local structural changes prevented the modification of tryptophan residues by N-bromosuccinimide (NBS), especially at Trp-602. Following Mg-Pi binding, Trp-75 and Trp-365, but not Trp-602, were slightly protected from structural modifications by NBS. These results reveal the conformation of H+-PPase is distinct in the presence of different ligands. Moreover, analyses of the Stern-Volmer relationship and steady-state fluorescence anisotropy also indicate that the local structure around Trp-602 is more exposed to solvent and varied under different environments. In addition, Trp-602 was identified to be a crucial residue in the H+-PPase that may potentially be involved in stabilizing the structure of the catalytic region by site-directed mutagenesis analysis.
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Schumacher K. pH in the plant endomembrane system-an import and export business. CURRENT OPINION IN PLANT BIOLOGY 2014; 22:71-76. [PMID: 25282587 DOI: 10.1016/j.pbi.2014.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/11/2014] [Accepted: 09/12/2014] [Indexed: 05/06/2023]
Abstract
pH homeostasis is an essential process in all plant cells and the maintenance of correct luminal pH in the compartments of the endomembrane system is important not only for secondary active transport but also for a variety of cellular functions including protein modification, sorting, and trafficking. Due to their electrogenicity primary H(+)-pumps cannot establish and control the often large proton-gradients single-handedly but require the co-action of other ion transporters that serve as either shunt conductances or proton-leaks. Here, I will thus focus on recent results that highlight the interplay of proton-pumps and proton-coupled transporters in controlling pH in the compartments of the plant endomembrane system.
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Affiliation(s)
- Karin Schumacher
- Dep. of Cell Biology, Centre for Organismal Studies (COS), Universität Heidelberg, 69120 Heidelberg, Germany.
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Neuhaus HE, Trentmann O. Regulation of transport processes across the tonoplast. FRONTIERS IN PLANT SCIENCE 2014; 5:460. [PMID: 25309559 PMCID: PMC4160088 DOI: 10.3389/fpls.2014.00460] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 08/26/2014] [Indexed: 05/24/2023]
Abstract
In plants, the vacuole builds up the cellular turgor and represents an important component in cellular responses to diverse stress stimuli. Rapid volume changes of cells, particularly of motor cells, like guard cells, are caused by variation of osmolytes and consequently of the water contents in the vacuole. Moreover, directed solute uptake into or release out of the large central vacuole allows adaptation of cytosolic metabolite levels according to the current physiological requirements and specific cellular demands. Therefore, solute passage across the vacuolar membrane, the tonoplast, has to be tightly regulated. Important principles in vacuolar transport regulation are changes of tonoplast transport protein abundances by differential expression of genes or changes of their activities, e.g., due to post-translational modification or by interacting proteins. Because vacuolar transport is in most cases driven by an electro-chemical gradient altered activities of tonoplast proton pumps significantly influence vacuolar transport capacities. Intense studies on individual tonoplast proteins but also unbiased system biological approaches have provided important insights into the regulation of vacuolar transport. This short review refers to selected examples of tonoplast proteins and their regulation, with special focus on protein phosphorylation.
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Affiliation(s)
| | - Oliver Trentmann
- *Correspondence: Oliver Trentmann, Plant Physiology, Department of Biology, Technische Universität Kaiserslautern, Postfach 3049, Kaiserslautern D-67653, Germany e-mail:
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Identification and characterization of an ecto-pyrophosphatase activity in intact epimastigotes of Trypanosoma rangeli. PLoS One 2014; 9:e106852. [PMID: 25203926 PMCID: PMC4159237 DOI: 10.1371/journal.pone.0106852] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 08/09/2014] [Indexed: 02/06/2023] Open
Abstract
In this study, we performed the molecular and biochemical characterization of an ecto-enzyme present in Trypanosoma rangeli that is involved with the hydrolysis of extracellular inorganic pyrophosphate. PCR analysis identified a putative proton-pyrophosphatase (H+-PPase) in the epimastigote forms of T. rangeli. This protein was recognized with Western blot and flow cytometry analysis using an antibody against the H+-PPase of Arabidopsis thaliana. Immunofluorescence microscopy confirmed that this protein is located in the plasma membrane of T. rangeli. Biochemical assays revealed that the optimum pH for the ecto-PPase activity was 7.5, as previously demonstrated for other organisms. Sodium fluoride (NaF) and aminomethylenediphosphonate (AMDP) were able to inhibit approximately 75% and 90% of the ecto-PPase activity, respectively. This ecto-PPase activity was stimulated in a dose-dependent manner by MgCl2. In the presence of MgCl2, this activity was inhibited by millimolar concentrations of CaCl2. The ecto-PPase activity of T. rangeli decreased with increasing cell proliferation in vitro, thereby suggesting a role for this enzyme in the acquisition of inorganic phosphate (Pi). Moreover, this activity was modulated by the extracellular concentration of Pi and increased approximately two-fold when the cells were maintained in culture medium depleted of Pi. All of these results confirmed the occurrence of an ecto-PPase located in the plasma membrane of T. rangeli that possibly plays an important role in phosphate metabolism of this protozoan.
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Tu Y, Jiang A, Gan L, Hossain M, Zhang J, Peng B, Xiong Y, Song Z, Cai D, Xu W, Zhang J, He Y. Genome duplication improves rice root resistance to salt stress. RICE (NEW YORK, N.Y.) 2014; 7:15. [PMID: 25184027 PMCID: PMC4151024 DOI: 10.1186/s12284-014-0015-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 07/15/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Salinity is a stressful environmental factor that limits the productivity of crop plants, and roots form the major interface between plants and various abiotic stresses. Rice is a salt-sensitive crop and its polyploid shows advantages in terms of stress resistance. The objective of this study was to investigate the effects of genome duplication on rice root resistance to salt stress. RESULTS Both diploid rice (HN2026-2x and Nipponbare-2x) and their corresponding tetraploid rice (HN2026-4x and Nipponbare-4x) were cultured in half-strength Murashige and Skoog medium with 150 mM NaCl for 3 and 5 days. Accumulations of proline, soluble sugar, malondialdehyde (MDA), Na(+) content, H(+) (proton) flux at root tips, and the microstructure and ultrastructure in rice roots were examined. We found that tetraploid rice showed less root growth inhibition, accumulated higher proline content and lower MDA content, and exhibited a higher frequency of normal epidermal cells than diploid rice. In addition, a protective gap appeared between the cortex and pericycle cells in tetraploid rice. Next, ultrastructural analysis showed that genome duplication improved membrane, organelle, and nuclei stability. Furthermore, Na(+) in tetraploid rice roots significantly decreased while root tip H(+) efflux in tetraploid rice significantly increased. CONCLUSIONS Our results suggest that genome duplication improves root resistance to salt stress, and that enhanced proton transport to the root surface may play a role in reducing Na(+) entrance into the roots.
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Affiliation(s)
- Yi Tu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
| | - Aiming Jiang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
- Faculty of Biochemistry and Environmental Engineering, Yunyang Teachers’ College, Shiyan 442000, P.R. China
| | - Lu Gan
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
- Faculty of Biochemistry and Environmental Engineering, Yunyang Teachers’ College, Shiyan 442000, P.R. China
| | - Mokter Hossain
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Jinming Zhang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
| | - Bo Peng
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
| | - Yuguo Xiong
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
| | - Zhaojian Song
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
| | - Detian Cai
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
| | - Weifeng Xu
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Jianhua Zhang
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Yuchi He
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, P.R. China
- School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
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Genome-wide comparative analysis of tonoplast intrinsic protein (TIP) genes in plants. Funct Integr Genomics 2014; 14:617-29. [PMID: 25095751 DOI: 10.1007/s10142-014-0389-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 07/13/2014] [Accepted: 07/21/2014] [Indexed: 10/24/2022]
Abstract
Tonoplast intrinsic proteins (TIPs) play a vital role in water transport across membranes. In the present study, we performed a comparative analysis of TIP genes in ten plant species including both monocots and dicots. A total of 100 TIP aquaporin genes were identified, and their relationships among the plant species were analyzed. Phylogenetic analysis was performed to evaluate the relationship of these genes within the plant species. Based on the phylogenetic analysis results, TIPs were classified into five distinct arbitrary groups (group I to group V), which represented TIP2, TIP5, TIP4, TIP1, and TIP3, respectively. Group I represented the largest arbitrary group, followed by group IV, in the phylogenetic tree. The result clearly indicates that TIP2 and TIP1 are abundant aquaporins and highly related among the species. In the present review, a comparative study of gene structure analysis between dicots and monocots has been performed to analyze their structural variation. Most of the predicted motifs are conserved among the species, signifying an evolutionary relationship. The gene expression analysis indicated that the expression of TIP genes varies during different developmental stages and also during stressed conditions. The results indicated a great degree of evolutionary relationship and variation in the expression levels of TIPs in plants.
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Segami S, Makino S, Miyake A, Asaoka M, Maeshima M. Dynamics of vacuoles and H+-pyrophosphatase visualized by monomeric green fluorescent protein in Arabidopsis: artifactual bulbs and native intravacuolar spherical structures. THE PLANT CELL 2014; 26:3416-34. [PMID: 25118245 PMCID: PMC4371836 DOI: 10.1105/tpc.114.127571] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We prepared Arabidopsis thaliana lines expressing a functional green fluorescent protein (GFP)-linked vacuolar H(+)-pyrophosphatase (H(+)-PPase) under the control of its own promoter to investigate morphological dynamics of vacuoles and tissue-specific expression of H(+)-PPase. The lines obtained had spherical structures in vacuoles with strong fluorescence, which are referred to as bulbs. Quantitative analyses revealed that the occurrence of the bulbs correlated with the amount of GFP. Next, we prepared a construct of H(+)-PPase linked with a nondimerizing GFP (mGFP); we detected no bulbs. These results indicate that the membranes adhere face-to-face by antiparallel dimerization of GFP, resulting in the formation of bulbs. In plants expressing H(+)-PPase-mGFP, intravacuolar spherical structures with double membranes, which differed from bulbs in fluorescence intensity and intermembrane spacing, were still observed in peripheral endosperm, pistil epidermis and hypocotyls. Four-dimensional imaging revealed the dynamics of formation, transformation, and disappearance of intravacuolar spherical structures and transvacuolar strands in living cells. Visualization of H(+)-PPase-mGFP revealed intensive accumulation of the enzyme, not only in dividing and elongating cells but also in mesophyll, phloem, and nectary cells, which may have high sugar content. Dynamic morphological changes including transformation of vacuolar structures between transvacuolar strands, intravacuolar sheet-like structures, and intravacuolar spherical structures were also revealed.
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Affiliation(s)
- Shoji Segami
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Sachi Makino
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Ai Miyake
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Mariko Asaoka
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Masayoshi Maeshima
- Laboratory of Cell Dynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
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Asaoka M, Segami S, Maeshima M. Identification of the critical residues for the function of vacuolar H+-pyrophosphatase by mutational analysis based on the 3D structure. ACTA ACUST UNITED AC 2014; 156:333-44. [DOI: 10.1093/jb/mvu046] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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48
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Faraco M, Spelt C, Bliek M, Verweij W, Hoshino A, Espen L, Prinsi B, Jaarsma R, Tarhan E, de Boer AH, Di Sansebastiano GP, Koes R, Quattrocchio FM. Hyperacidification of vacuoles by the combined action of two different P-ATPases in the tonoplast determines flower color. Cell Rep 2014; 6:32-43. [PMID: 24388746 DOI: 10.1016/j.celrep.2013.12.009] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 10/14/2013] [Accepted: 12/04/2013] [Indexed: 10/25/2022] Open
Abstract
The acidification of endomembrane compartments is essential for enzyme activities, sorting, trafficking, and trans-membrane transport of various compounds. Vacuoles are mildly acidic in most plant cells because of the action of V-ATPase and/or pyrophosphatase proton pumps but are hyperacidified in specific cells by mechanisms that remained unclear. Here, we show that the blue petal color of petunia ph mutants is due to a failure to hyperacidify vacuoles. We report that PH1 encodes a P3B-ATPase, hitherto known as Mg2(+) transporters in bacteria only, that resides in the vacuolar membrane (tonoplast). In vivo nuclear magnetic resonance and genetic data show that PH1 is required and, together with the tonoplast H(+) P3A-ATPase PH5, sufficient to hyperacidify vacuoles. PH1 has no H(+) transport activity on its own but can physically interact with PH5 and boost PH5 H(+) transport activity. Hence, the hyperacidification of vacuoles in petals, and possibly other tissues, relies on a heteromeric P-ATPase pump.
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Affiliation(s)
- Marianna Faraco
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | - Cornelis Spelt
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | - Mattijs Bliek
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | - Walter Verweij
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | - Atsushi Hoshino
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands; National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, 444-8585 Aichi, Japan; Department of Basic Biology, The Graduate University for Advanced Studies (Sokendai), 444-8585 Okazaki, Japan
| | - Luca Espen
- Dipartimento Scienze Agrarie e Ambientali, Produzione, Territorio, Agroenergia, Università degli Studi di Milano, Via G. Celoria 2, 20133 Milano, Italy
| | - Bhakti Prinsi
- Dipartimento Scienze Agrarie e Ambientali, Produzione, Territorio, Agroenergia, Università degli Studi di Milano, Via G. Celoria 2, 20133 Milano, Italy
| | - Rinse Jaarsma
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | - Eray Tarhan
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | - Albertus H de Boer
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands
| | | | - Ronald Koes
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands.
| | - Francesca M Quattrocchio
- Department of Molecular Cell Biology, Graduate School of Experimental Plant Sciences, VU University, De Boelelaan 1085, 1081HV Amsterdam, the Netherlands.
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Viotti C. ER and vacuoles: never been closer. FRONTIERS IN PLANT SCIENCE 2014; 5:20. [PMID: 24550928 PMCID: PMC3913007 DOI: 10.3389/fpls.2014.00020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 01/17/2014] [Indexed: 05/02/2023]
Abstract
The endoplasmic reticulum (ER) represents the gateway for intracellular trafficking of membrane proteins, soluble cargoes and lipids. In all eukaryotes, the best described mechanism of exiting the ER is via COPII-coated vesicles, which transport both membrane proteins and soluble cargoes to the cis-Golgi. The vacuole, together with the plasma membrane, is the most distal point of the secretory pathway, and many vacuolar proteins are transported from the ER through intermediate compartments. However, past results and recent findings demonstrate the presence of alternative transport routes from the ER towards the tonoplast, which are independent of Golgi- and post-Golgi trafficking. Moreover, the transport mechanism of the vacuolar proton pumps VHA-a3 and AVP1 challenges the current model of vacuole biogenesis, pointing to the endoplasmic reticulum for being the main membrane source for the biogenesis of the plant lytic compartment. This review gives an overview of the current knowledge on the transport routes towards the vacuole and discusses the possible mechanism of vacuole biogenesis in plants.
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Affiliation(s)
- Corrado Viotti
- *Correspondence: Corrado Viotti, Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Linnéusväg 6, 90187 Umeå, Sweden e-mail:
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50
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Regulation of PPi Levels Through the Vacuolar Membrane H+-Pyrophosphatase. PROGRESS IN BOTANY 2014. [DOI: 10.1007/978-3-642-38797-5_5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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