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García-Contreras R, de la Mora J, Mora-Montes HM, Martínez-Álvarez JA, Vicente-Gómez M, Padilla-Vaca F, Vargas-Maya NI, Franco B. The inorganic pyrophosphatases of microorganisms: a structural and functional review. PeerJ 2024; 12:e17496. [PMID: 38938619 PMCID: PMC11210485 DOI: 10.7717/peerj.17496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/09/2024] [Indexed: 06/29/2024] Open
Abstract
Pyrophosphatases (PPases) are enzymes that catalyze the hydrolysis of pyrophosphate (PPi), a byproduct of the synthesis and degradation of diverse biomolecules. The accumulation of PPi in the cell can result in cell death. Although the substrate is the same, there are variations in the catalysis and features of these enzymes. Two enzyme forms have been identified in bacteria: cytoplasmic or soluble pyrophosphatases and membrane-bound pyrophosphatases, which play major roles in cell bioenergetics. In eukaryotic cells, cytoplasmic enzymes are the predominant form of PPases (c-PPases), while membrane enzymes (m-PPases) are found only in protists and plants. The study of bacterial cytoplasmic and membrane-bound pyrophosphatases has slowed in recent years. These enzymes are central to cell metabolism and physiology since phospholipid and nucleic acid synthesis release important amounts of PPi that must be removed to allow biosynthesis to continue. In this review, two aims were pursued: first, to provide insight into the structural features of PPases known to date and that are well characterized, and to provide examples of enzymes with novel features. Second, the scientific community should continue studying these enzymes because they have many biotechnological applications. Additionally, in this review, we provide evidence that there are m-PPases present in fungi; to date, no examples have been characterized. Therefore, the diversity of PPase enzymes is still a fruitful field of research. Additionally, we focused on the roles of H+/Na+ pumps and m-PPases in cell bioenergetics. Finally, we provide some examples of the applications of these enzymes in molecular biology and biotechnology, especially in plants. This review is valuable for professionals in the biochemistry field of protein structure-function relationships and experts in other fields, such as chemistry, nanotechnology, and plant sciences.
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Affiliation(s)
- Rodolfo García-Contreras
- Departamento de Microbiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Javier de la Mora
- Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Héctor Manuel Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - José A. Martínez-Álvarez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Marcos Vicente-Gómez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Felipe Padilla-Vaca
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Naurú Idalia Vargas-Maya
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Bernardo Franco
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
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Sun L, Deng R, Liu J, Lai M, Wu J, Liu X, Shahid MQ. An overview of sucrose transporter (SUT) genes family in rice. Mol Biol Rep 2022; 49:5685-5695. [PMID: 35699859 DOI: 10.1007/s11033-022-07611-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 05/17/2022] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Photosynthesis provides the energy basis for the life activities of plants by producing organic compounds, mainly sugar. As the main energy form of photosynthesis, sugar affects the growth and development of plants. During long-distance transportation, sucrose is the main form of transportation. The rate of sugar transport and the allocation of carbohydrates affect the biomass of crops and are closely related to the reproductive growth of crops. MAIN TEXT The transportation of sugar is divided into active transportation and passive transportation. So how does the sucrose transporters (SUT) genes, which are the main carriers of sucrose in active transportation, affect the performance of rice agronomic traits is still to be explored. In this article, we describe the structure of inflorescence and review the transport forms and metabolic processes of sucrose in rice, such as how CO2 is fixed, carbohydrate assimilation, and transport of organic matter. Sucrose transporters exhibited remarkable effects on the development of reproductive organs in rice. CONCLUSIONS Here, the effects of different factors, such as the effects of anthers morphology on starch enrichment of pollen, effects of biotic and abiotic factors on sucrose transporters, effects of changes in trace elements on sucrose transporters, were discussed. Moreover, the regulation of transcription or translation level provides ideas for future research on sucrose transporters.
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Affiliation(s)
- Lixia Sun
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Ruilian Deng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Jingwen Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Mingyu Lai
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Jinwen Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Xiangdong Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China.,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China
| | - Muhammad Qasim Shahid
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, 510642, China. .,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, 510642, China. .,Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangzhou, 510642, China. .,College of Agriculture, South China Agricultural University, Guangzhou, 510642, China.
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Dai C, Dai X, Qu H, Men Q, Liu J, Yu L, Gu M, Xu G. The rice phosphate transporter OsPHT1;7 plays a dual role in phosphorus redistribution and anther development. PLANT PHYSIOLOGY 2022; 188:2272-2288. [PMID: 35088867 PMCID: PMC8968348 DOI: 10.1093/plphys/kiac030] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 12/22/2021] [Indexed: 05/08/2023]
Abstract
Inorganic phosphate (Pi) is the predominant form of phosphorus (P) readily accessible to plants, and Pi Transporter 1 (PHT1) genes are the major contributors to root Pi uptake. However, the mechanisms underlying the transport and recycling of Pi within plants, which are vital for optimizing P use efficiency, remain elusive. Here, we characterized a functionally unknown rice (Oryza sativa) PHT1 member barely expressed in roots, OsPHT1;7. Yeast complementation and Xenopus laevis oocyte assay demonstrated that OsPHT1;7 could mediate Pi transport. Reverse-transcription quantitative polymerase chain reaction and histochemical analyses showed that OsPHT1;7 was preferentially expressed in source leaves and nodes. A further fine-localization analysis by immunostaining showed that OsPHT1;7 expression was restricted in the vascular bundle (VB) sheath and phloem of source leaves as well as in the phloem of regular/diffuse- and enlarged-VBs of nodes. In accordance with this expression pattern, mutation of OsPHT1;7 led to increased and decreased P distribution in source (old leaves) and sink organs (new leaves/panicles), respectively, indicating that OsPHT1;7 is involved in P redistribution. Furthermore, OsPHT1;7 showed an overwhelmingly higher transcript abundance in anthers than other PHT1 members, and ospht1;7 mutants were impaired in P accumulation in anthers but not in pistils or husks. Moreover, the germination of pollen grains was significantly inhibited upon OsPHT1;7 mutation, leading to a >80% decrease in seed-setting rate and grain yield. Taken together, our results provide evidence that OsPHT1;7 is a crucial Pi transporter for Pi transport and recycling within rice plants, stimulating both vegetative and reproductive growth.
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Affiliation(s)
- Changrong Dai
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiaoli Dai
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing 210095, China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, 210095 China
| | - Hongye Qu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing 210095, China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, 210095 China
| | - Qin Men
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Jingyang Liu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Ling Yu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing 210095, China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, 210095 China
| | | | - Guohua Xu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River, Nanjing 210095, China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, 210095 China
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Wu Y, Fang W, Peng W, Jiang M, Chen G, Xiong F. Sucrose transporter in rice. PLANT SIGNALING & BEHAVIOR 2021; 16:1952373. [PMID: 34269147 PMCID: PMC8525984 DOI: 10.1080/15592324.2021.1952373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Plant photosynthesis processes play vital roles in crop plant development. Understanding carbohydrate partitioning via sugar transport is one of the potential ways to modify crop biomass, which is tightly linked to plant architecture, such as plant height and panicle size. Based on the literature, we highlight recent findings to summarize phloem loading by sucrose transport in rice. In rice, sucrose transporters, OsSUTs (sucrose transporters) and OsSWEETs (sugars are eventually exported transporters) import sucrose and export cells between phloem parenchyma cells and companion cells. Before sucrose transporters perform their functions, several transcription factors can induce sucrose transporter gene transcription levels, such as Oryza sativa DNA binding with one finger 11 (OsDOF11) and Oryza sativa Nuclear Factor Y B1 (OsNF-YB1). In addition to native regulator genes, environmental factors, such as CO2 concentration, drought stress and increased temperature, also affect sucrose transporter gene transcription levels. However, more research work is needed on formation regulation webs. Elucidation of the phloem loading mechanism could improve our understanding of rice development under multiple conditions and facilitate its manipulation to increase crop productivity.
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Affiliation(s)
- Yunfei Wu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture &agri-product Safety, Yangzhou University, Yangzhou, China
| | - wenchun Fang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture &agri-product Safety, Yangzhou University, Yangzhou, China
| | - Wangmenghan Peng
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture &agri-product Safety, Yangzhou University, Yangzhou, China
| | - Min Jiang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture &agri-product Safety, Yangzhou University, Yangzhou, China
| | - Gang Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture &agri-product Safety, Yangzhou University, Yangzhou, China
| | - Fei Xiong
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops/Joint International Research Laboratory of Agriculture &agri-product Safety, Yangzhou University, Yangzhou, China
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Menadue DJ, Riboni M, Baumann U, Schilling RK, Plett DC, Roy SJ. Proton-pumping pyrophosphatase homeolog expression is a dynamic trait in bread wheat ( Triticum aestivum). PLANT DIRECT 2021; 5:e354. [PMID: 34646976 PMCID: PMC8496507 DOI: 10.1002/pld3.354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/20/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Proton-pumping pyrophosphatases (H+-PPases) have been shown to enhance biomass and yield. However, to date, there has been little work towards identify genes encoding H+-PPases in bread wheat (Triticum aestivum) (TaVPs) and limited knowledge on how the expression of these genes varies across different growth stages and tissue types. In this study, the IWGSC database was used to identify two novel TaVP genes, TaVP4 and TaVP5, and elucidate the complete homeolog sequences of the three known TaVP genes, bringing the total number of bread wheat TaVPs from 9 to 15. Gene expression levels of each TaVP homeolog were assessed using quantitative real-time PCR (qRT-PCR) in four diverse wheat varieties in terms of phenotypic traits related to high vacuolar pyrophosphatase expression. Homeolog expression was analyzed across multiple tissue types and developmental stages. Expression levels of the TaVP homeologs were found to vary significantly between varieties, tissues and plant developmental stages. During early development (Z10 and Z13), expressions of TaVP1 and TaVP2 homeologs were higher in shoot tissue than root tissue, with both shoot and root expression increasing in later developmental stages (Z22). TaVP2-D was expressed in all varieties and tissue types and was the most highly expressed homeolog at all developmental stages. Expression of the TaVP3 homeologs was restricted to developing grain (Z75), while TaVP4 homeolog expression was higher at Z22 than earlier developmental stages. Variation in TaVP4B was detected among varieties at Z22 and Z75, with Buck Atlantico (high biomass) and Scout (elite Australian cultivar) having the highest levels of expression. These findings offer a comprehensive overview of the bread wheat H+-PPase family and identify variation in TaVP homeolog expression that will be of use to improve the growth, yield, and abiotic stress tolerance of bread wheat.
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Affiliation(s)
- Daniel Jamie Menadue
- School of Agriculture, Food and WineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Centre for Plant Functional GenomicsThe University of AdelaideUrrbraeSouth AustraliaAustralia
| | - Matteo Riboni
- School of Agriculture, Food and WineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Centre for Plant Functional GenomicsThe University of AdelaideUrrbraeSouth AustraliaAustralia
| | - Ute Baumann
- School of Agriculture, Food and WineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Centre for Plant Functional GenomicsThe University of AdelaideUrrbraeSouth AustraliaAustralia
| | - Rhiannon Kate Schilling
- School of Agriculture, Food and WineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Centre for Plant Functional GenomicsThe University of AdelaideUrrbraeSouth AustraliaAustralia
- Department of Primary Industries and RegionsSouth Australian Research and Development InstituteUrrbraeSouth AustraliaAustralia
| | - Darren Craig Plett
- School of Agriculture, Food and WineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Plant Phenomics Facility, The Plant AcceleratorThe University of AdelaideAdelaideSouth AustraliaAustralia
| | - Stuart John Roy
- School of Agriculture, Food and WineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Australian Centre for Plant Functional GenomicsThe University of AdelaideUrrbraeSouth AustraliaAustralia
- ARC Industrial Transformation Research Hub for Wheat in a Hot and Dry ClimateUniversity of AdelaideAdelaideSouth AustraliaAustralia
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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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Yao D, Gonzales-Vigil E, Mansfield SD. Arabidopsis sucrose synthase localization indicates a primary role in sucrose translocation in phloem. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:1858-1869. [PMID: 31805187 PMCID: PMC7242074 DOI: 10.1093/jxb/erz539] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/05/2019] [Indexed: 05/24/2023]
Abstract
Sucrose synthase (SuSy) is one of two enzyme families capable of catalyzing the first degradative step in sucrose utilization. Several earlier studies examining SuSy mutants in Arabidopsis failed to identify obvious phenotypic abnormalities compared with wild-type plants in normal growth environments, and as such a functional role for SuSy in the previously proposed cellulose biosynthetic process remains unclear. Our study systematically evaluated the precise subcellular localization of all six isoforms of Arabidopsis SuSy via live-cell imaging. We showed that yellow fluorescent protein (YFP)-labeled SuSy1 and SuSy4 were expressed exclusively in phloem companion cells, and the sus1/sus4 double mutant accumulated sucrose under hypoxic conditions. SuSy5 and SuSy6 were found to be parietally localized in sieve elements and restricted only to the cytoplasm. SuSy2 was present in the endosperm and embryo of developing seeds, and SuSy3 was localized to the embryo and leaf stomata. No single isoform of SuSy was detected in developing xylem tissue of elongating stem, the primary site of cellulose deposition in plants. SuSy1 and SuSy4 were also undetectable in the protoxylem tracheary elements, which were induced by the vascular-related transcription factor VND7 during secondary cell wall formation. These findings implicate SuSy in the biological events related to sucrose translocation in phloem.
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Affiliation(s)
- Danyu Yao
- Department of Wood Science, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, British Columbia, Canada
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Regmi KC, Yogendra K, Farias JG, Li L, Kandel R, Yadav UP, Sha S, Trittermann C, Short L, George J, Evers J, Plett D, Ayre BG, Roy SJ, Gaxiola RA. Improved Yield and Photosynthate Partitioning in AVP1 Expressing Wheat ( Triticum aestivum) Plants. FRONTIERS IN PLANT SCIENCE 2020; 11:273. [PMID: 32256508 PMCID: PMC7090233 DOI: 10.3389/fpls.2020.00273] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 02/21/2020] [Indexed: 05/28/2023]
Abstract
A fundamental factor to improve crop productivity involves the optimization of reduced carbon translocation from source to sink tissues. Here, we present data consistent with the positive effect that the expression of the Arabidopsis thaliana H+-PPase (AVP1) has on reduced carbon partitioning and yield increases in wheat. Immunohistochemical localization of H+-PPases (TaVP) in spring wheat Bobwhite L. revealed the presence of this conserved enzyme in wheat vasculature and sink tissues. Of note, immunogold imaging showed a plasma membrane localization of TaVP in sieve element- companion cell complexes of Bobwhite source leaves. These data together with the distribution patterns of a fluorescent tracer and [U14C]-sucrose are consistent with an apoplasmic phloem-loading model in wheat. Interestingly, 14C-labeling experiments provided evidence for enhanced carbon partitioning between shoots and roots, and between flag leaves and milk stage kernels in AVP1 expressing Bobwhite lines. In keeping, there is a significant yield improvement triggered by the expression of AVP1 in these lines. Green house and field grown transgenic wheat expressing AVP1 also produced higher grain yield and number of seeds per plant, and exhibited an increase in root biomass when compared to null segregants. Another agriculturally desirable phenotype showed by AVP1 Bobwhite plants is a robust establishment of seedlings.
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Affiliation(s)
- Kamesh C. Regmi
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Kalenahalli Yogendra
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
| | - Júlia Gomes Farias
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Lin Li
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Raju Kandel
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Umesh P. Yadav
- Department of Biological Sciences, BioDiscovery Institute, University of North Texas, Denton, TX, United States
| | - Shengbo Sha
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
| | - Christine Trittermann
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
| | - Laura Short
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
| | - Jessey George
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
| | - John Evers
- Department of Biological Sciences, BioDiscovery Institute, University of North Texas, Denton, TX, United States
| | - Darren Plett
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
| | - Brian G. Ayre
- Department of Biological Sciences, BioDiscovery Institute, University of North Texas, Denton, TX, United States
| | - Stuart John Roy
- Australian Centre for Plant Functional Genomics, The University of Adelaide, Adelaide, SA, Australia
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Zhang Y, Feng X, Wang L, Su Y, Chu Z, Sun Y. The structure, functional evolution, and evolutionary trajectories of the H +-PPase gene family in plants. BMC Genomics 2020; 21:195. [PMID: 32122295 PMCID: PMC7053079 DOI: 10.1186/s12864-020-6604-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 02/21/2020] [Indexed: 08/16/2023] Open
Abstract
BACKGROUND The H+-PPase (pyrophosphatase) gene family is an important class of proton transporters that play key roles in plant development and stress resistance. Although the physiological and biochemical functions of H+-PPases are well characterized, the structural evolution and functional differentiation of this gene family remain unclear. RESULTS We identified 124 H+-PPase members from 27 plant species using complete genomic data obtained from algae to angiosperms. We found that all analyzed plants carried H+-PPase genes, and members were not limited to the two main types (type I and II). Differentiation of this gene family occurred early in evolutionary history, probably prior to the emergence of algae. The type I and II H+-PPase genes were retained during the subsequent evolution of higher plants, and their copy numbers increased rapidly in some angiosperms following whole-genome duplication (WGD) events, with obvious expression pattern differentiation among the new copies. We found significant functional divergence between type I and II H+-PPase genes, with both showing evidence for positive selection pressure. We classified angiosperm type I H+-PPases into subtypes Ia and non-Ia, which probably differentiated at an early stage of angiosperm evolution. Compared with non-Ia subtype, the Ia subtype appears to confer some advantage in angiosperms, as it is highly conserved and abundantly expressed, but shows no evidence for positive selection. CONCLUSIONS We hypothesized that there were many types of H+-PPase genes in the plant ancestral genome, and that different plant groups retained different types of these genes. In the early stages of angiosperm evolution, the type I H+-PPase genes differentiated into various subtypes. In addition, the expression pattern varied not only among genes of different types or subtypes, but also among copies of the same subtype. Based on the expression patterns and copy numbers of H+-PPase genes in higher plants, we propose two possible evolutionary trajectories for this gene family.
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Affiliation(s)
- Yiming Zhang
- College of Life Sciences, Langfang Normal University, Langfang, 065000, China
| | - Xue Feng
- College of Life Sciences, Langfang Normal University, Langfang, 065000, China
| | - Lihui Wang
- College of Plant Protection, Fujian Agricultural and Forestry University, Fuzhou, 350000, China
| | - Yanping Su
- College of Life Sciences, Langfang Normal University, Langfang, 065000, China
| | - Zhuodong Chu
- College of Life Sciences, Langfang Normal University, Langfang, 065000, China
| | - Yanxiang Sun
- College of Life Sciences, Langfang Normal University, Langfang, 065000, China.
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Altered sucrose metabolism and plant growth in transgenic Populus tomentosa with altered sucrose synthase PtSS3. Transgenic Res 2019; 29:125-134. [PMID: 31853721 DOI: 10.1007/s11248-019-00184-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/13/2019] [Indexed: 11/27/2022]
Abstract
Improvement of wood quality is an important focus of forest genetics and breeding research. Sucrose synthase (SS) catalyzes the reaction of sucrose and uridine diphosphate into uridine diphosphate glucose and fructose. It is a key enzyme involved in cell wall formation during secondary growth by providing the UDP-Glucose substrate for cellulose biosynthesis. In this study, we isolated the single-copy gene PtSS3 from the SS gene family of Populus tomentosa and analyzed its structure. To identify its function in secondary growth, we generated 19 transgenic lines of P. tomentosa using PtSS3 overexpression (OE) and artificial microRNA (amiRNA) constructs. We also performed comprehensive analyses of the transgenic P. tomentosa plants, including phenotypic analyses, quantitative real-time PCR, enzyme activity assays and sugar metabolism. We found significantly higher PtSS3 enzyme activity, fructose, and glucose levels and significantly lower sucrose levels in the stems and leaves of OE-PtSS3 plants. The opposite trend was observed in the amiRNA-PtSS3 lines. Gene expression analyses showed that PtSS3 transcript levels in stems and leaves were up-regulated in the OE-PtSS3 lines and down-regulated in the amiRNA-PtSS3 lines, and the OE-PtSS3 plants grew taller than the wild-type and amiRNA-PtSS3 plants. These findings indicate that PtSS3 plays an important role in sucrose metabolism and growth of trees.
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Chen L, Deng Y, Zhu H, Hu Y, Jiang Z, Tang S, Wang S, Ding Y. The Initiation of Inferior Grain Filling is Affected by Sugar Translocation Efficiency in Large Panicle Rice. RICE (NEW YORK, N.Y.) 2019; 12:75. [PMID: 31617022 PMCID: PMC6794335 DOI: 10.1186/s12284-019-0333-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 09/11/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND Large panicle rice has a large sink capacity, but inferior spikelet filling is poor in this variety of rice due to asynchronous grain filling. The understanding of the factors that cause asynchronous grain filling will help to propose a model for how to regulate the rice inferior spikelets grain filling. RESULTS In this study, two large panicle rice varieties, W1844 and CJ03, with the same sink capacity but with differences in asynchronous grain filling were used. The difference in the grain filling rate between superior and inferior spikelets in W1844 was much smaller than that in CJ03. We found that superior spikelet filling was initiated earlier in W1844 than in CJ03. The source-to-sink translocation rate of sucrose during the grain filling stage was more efficient in W1844 than in CJ03, and the gene expression levels of sucrose transporters (OsSUTs) were higher in W1844 functional leaves than in those of CJ03. In addition, carbon output, the transport ratio, and the contribution rate from the stem and sheath to the panicle were much higher at the early filling stage than at later filling stages in W1844. CONCLUSION Efficient sugar translocation can satisfy high sink strength, and also the strong sink activity can facilitate the sugar unloading in spikelets. All the above results indicate that an efficient sugar translocation rate at the early grain filling stage can improve sink strength and inferior grain filling initiation. Strategies to limit asynchronous grain filling in rice were also discussed based on our findings.
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Affiliation(s)
- Lin Chen
- College of Agriculture, Nanjing Agricultural University, Nanjing, China.
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China.
- Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing, China.
- College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China.
| | - Yao Deng
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Honglei Zhu
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Yuxiang Hu
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - Zhengrong Jiang
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
| | - She Tang
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
- Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing, China
| | - Shaohua Wang
- College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China
- Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing, China
| | - Yanfeng Ding
- College of Agriculture, Nanjing Agricultural University, Nanjing, China.
- Key Laboratory of Crop Physiology & Ecology in Southern China, Ministry of Agricultural University, Nanjing, China.
- Jiangsu Collaborative Innovation Center for Modern Crop Production, Nanjing, China.
- College of Agriculture, Nanjing Agricultural University, Nanjing, 210095, China.
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Stein O, Granot D. An Overview of Sucrose Synthases in Plants. FRONTIERS IN PLANT SCIENCE 2019; 10:95. [PMID: 30800137 PMCID: PMC6375876 DOI: 10.3389/fpls.2019.00095] [Citation(s) in RCA: 253] [Impact Index Per Article: 50.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/21/2019] [Indexed: 05/04/2023]
Abstract
Sucrose is the end product of photosynthesis and the primary sugar transported in the phloem of most plants. Sucrose synthase (SuSy) is a glycosyl transferase enzyme that plays a key role in sugar metabolism, primarily in sink tissues. SuSy catalyzes the reversible cleavage of sucrose into fructose and either uridine diphosphate glucose (UDP-G) or adenosine diphosphate glucose (ADP-G). The products of sucrose cleavage by SuSy are available for many metabolic pathways, such as energy production, primary-metabolite production, and the synthesis of complex carbohydrates. SuSy proteins are usually homotetramers with an average monomeric molecular weight of about 90 kD (about 800 amino acids long). Plant SuSy isozymes are mainly located in the cytosol or adjacent to plasma membrane, but some SuSy proteins are found in the cell wall, vacuoles, and mitochondria. Plant SUS gene families are usually small, containing between four to seven genes, with distinct exon-intron structures. Plant SUS genes are divided into three separate clades, which are present in both monocots and dicots. A comprehensive phylogenetic analysis indicates that a first SUS duplication event may have occurred before the divergence of the gymnosperms and angiosperms and a second duplication event probably occurred in a common angiosperm ancestor, leading to the existence of all three clades in both monocots and dicots. Plants with reduced SuSy activity have been shown to have reduced growth, reduced starch, cellulose or callose synthesis, reduced tolerance to anaerobic-stress conditions and altered shoot apical meristem function and leaf morphology. Plants overexpressing SUS have shown increased growth, increased xylem area and xylem cell-wall width, and increased cellulose and starch contents, making SUS high-potential candidate genes for the improvement of agricultural traits in crop plants. This review summarizes the current knowledge regarding plant SuSy, including newly discovered possible developmental roles for SuSy in meristem functioning that involve sugar and hormonal signaling.
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Affiliation(s)
| | - David Granot
- Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
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Regmi KC, Li L, Gaxiola RA. Alternate Modes of Photosynthate Transport in the Alternating Generations of Physcomitrella patens. FRONTIERS IN PLANT SCIENCE 2017; 8:1956. [PMID: 29181017 PMCID: PMC5693889 DOI: 10.3389/fpls.2017.01956] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 10/30/2017] [Indexed: 05/06/2023]
Abstract
Physcomitrella patens has emerged as a model moss system to investigate the evolution of various plant characters in early land plant lineages. Yet, there is merely a disparate body of ultrastructural and physiological evidence from other mosses to draw inferences about the modes of photosynthate transport in the alternating generations of Physcomitrella. We performed a series of ultrastructural, fluorescent tracing, physiological, and immunohistochemical experiments to elucidate a coherent model of photosynthate transport in this moss. Our ultrastructural observations revealed that Physcomitrella is an endohydric moss with water-conducting and putative food-conducting cells in the gametophytic stem and leaves. Movement of fluorescent tracer 5(6)-carboxyfluorescein diacetate revealed that the mode of transport in the gametophytic generation is symplasmic and is mediated by plasmodesmata, while there is a diffusion barrier composed of transfer cells that separates the photoautotrophic gametophyte from the nutritionally dependent heterotrophic sporophyte. We posited that, analogous to what is found in apoplasmically phloem loading higher plants, the primary photosynthate sucrose, is actively imported into the transfer cells by sucrose/H+ symporters (SUTs) that are, in turn, powered by P-type ATPases, and that the transfer cells harbor an ATP-conserving Sucrose Synthase (SUS) pathway. Supporting our hypothesis was the finding that a protonophore (2,4-dinitrophenol) and a SUT-specific inhibitor (diethyl pyrocarbonate) reduced the uptake of radiolabeled sucrose into the sporangia. In situ immunolocalization of P-type ATPase, Sucrose Synthase, and Proton Pyrophosphatase - all key components of the SUS pathway - showed that these proteins were prominently localized in the transfer cells, providing further evidence consistent with our argument.
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Sun T, Xu L, Sun H, Yue Q, Zhai H, Yao Y. VvVHP1; 2 Is Transcriptionally Activated by VvMYBA1 and Promotes Anthocyanin Accumulation of Grape Berry Skins via Glucose Signal. FRONTIERS IN PLANT SCIENCE 2017; 8:1811. [PMID: 29104582 PMCID: PMC5655013 DOI: 10.3389/fpls.2017.01811] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 10/05/2017] [Indexed: 05/14/2023]
Abstract
In this work, four vacuolar H+-PPase (VHP) genes were identified in the grape genome. Among them, VvVHP1; 2 was strongly expressed in berry skin and its expression exhibited high correlations to anthocyanin content of berry skin during berry ripening and under ABA and UVB treatments. VvVHP1; 2 was transcriptionally activated directly by VvMYBA1, and VvVHP1; 2 overexpression promoted anthocyanin accumulation in berry skins and Arabidopsis leaves; therefore, VvVHP1; 2 mediated VvMYBA1-regulated berry pigmentation. On the other hand, RNA-Seq analysis of WT and transgenic berry skins revealed that carbohydrate metabolism, flavonoid metabolism and regulation and solute carrier family expression were the most clearly altered biological processes. Further experiments elucidated that VvVHP1; 2 overexpression up-regulated the expression of the genes related to anthocyanin biosynthesis and transport via hexokinase-mediated glucose signal and thereby promoted anthocyanin accumulation in berry skins and Arabidopsis leaves. Additionally, modifications of sugar status caused by enhanced hexokinase activities likely play a key role in VvVHP1; 2-induced sugar signaling.
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15
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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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16
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Gaxiola RA, Regmi K, Hirschi KD. Moving On Up: H(+)-PPase Mediated Crop Improvement. Trends Biotechnol 2016; 34:347-349. [PMID: 26818803 DOI: 10.1016/j.tibtech.2015.12.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 12/30/2015] [Accepted: 12/31/2015] [Indexed: 10/22/2022]
Abstract
Upregulation of H(+)-PPase in diverse crop systems triggers agriculturally beneficial phenotypes including augmented stress tolerance, improved water and nutrient use efficiencies, and increased biomass and yield. We argue that further research is warranted to maximize the full potential of this simple and successful biotechnology.
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Affiliation(s)
- Roberto A Gaxiola
- School of Life Sciences, Arizona State University, Tempe, AZ 852872, USA.
| | - Kamesh Regmi
- School of Life Sciences, Arizona State University, Tempe, AZ 852872, USA
| | - Kendal D Hirschi
- USDA/ARS Children's Nutrition Research Center, Baylor College of Medicine, 1100 Bates Street, Houston, TX 77030, USA
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17
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Khadilkar AS, Yadav UP, Salazar C, Shulaev V, Paez-Valencia J, Pizzio GA, Gaxiola RA, Ayre BG. Constitutive and Companion Cell-Specific Overexpression of AVP1, Encoding a Proton-Pumping Pyrophosphatase, Enhances Biomass Accumulation, Phloem Loading, and Long-Distance Transport. PLANT PHYSIOLOGY 2016; 170:401-14. [PMID: 26530315 PMCID: PMC4704589 DOI: 10.1104/pp.15.01409] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/30/2015] [Indexed: 05/18/2023]
Abstract
Plant productivity is determined in large part by the partitioning of assimilates between the sites of production and the sites of utilization. Proton-pumping pyrophosphatases (H(+)-PPases) are shown to participate in many energetic plant processes, including general growth and biomass accumulation, CO2 fixation, nutrient acquisition, and stress responses. H(+)-PPases have a well-documented role in hydrolyzing pyrophosphate (PPi) and capturing the released energy to pump H(+) across the tonoplast and endomembranes to create proton motive force (pmf). Recently, an additional role for H(+)-PPases in phloem loading and biomass partitioning was proposed. In companion cells (CCs) of the phloem, H(+)-PPases localize to the plasma membrane rather than endomembranes, and rather than hydrolyzing PPi to create pmf, pmf is utilized to synthesize PPi. Additional PPi in the CCs promotes sucrose oxidation and ATP synthesis, which the plasma membrane P-type ATPase in turn uses to create more pmf for phloem loading of sucrose via sucrose-H(+) symporters. To test this model, transgenic Arabidopsis (Arabidopsis thaliana) plants were generated with constitutive and CC-specific overexpression of AVP1, encoding type 1 ARABIDOPSIS VACUOLAR PYROPHOSPHATASE1. Plants with both constitutive and CC-specific overexpression accumulated more biomass in shoot and root systems. (14)C-labeling experiments showed enhanced photosynthesis, phloem loading, phloem transport, and delivery to sink organs. The results obtained with constitutive and CC-specific promoters were very similar, such that the growth enhancement mediated by AVP1 overexpression can be attributed to its role in phloem CCs. This supports the model for H(+)-PPases functioning as PPi synthases in the phloem by arguing that the increases in biomass observed with AVP1 overexpression stem from improved phloem loading and transport.
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Affiliation(s)
- Aswad S Khadilkar
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Umesh P Yadav
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Carolina Salazar
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Vladimir Shulaev
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Julio Paez-Valencia
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Gaston A Pizzio
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Roberto A Gaxiola
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
| | - Brian G Ayre
- Department of Biological Sciences, University of North Texas, Denton, Texas 76203 (A.S.K., U.P.Y., C.S., V.S., B.G.A.); andSchool of Life Sciences, Arizona State University, Tempe, Arizona 85287 (J.P.-V., G.A.P., R.A.G.)
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