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Conrado AC, Lemes Jorge G, Rao RSP, Xu C, Xu D, Li-Beisson Y, Thelen JJ. Evolution of the regulatory subunits for the heteromeric acetyl-CoA carboxylase. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230353. [PMID: 39343023 DOI: 10.1098/rstb.2023.0353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 07/22/2024] [Accepted: 09/02/2024] [Indexed: 10/01/2024] Open
Abstract
The committed step for de novo fatty acid (FA) synthesis is the ATP-dependent carboxylation of acetyl-coenzyme A catalysed by acetyl-CoA carboxylase (ACCase). In most plants, ACCase is a multi-subunit complex orthologous to prokaryotes. However, unlike prokaryotes, the plant and algal orthologues are comprised both catalytic and additional dedicated regulatory subunits. Novel regulatory subunits, biotin lipoyl attachment domain-containing proteins (BADC) and carboxyltransferase interactors (CTI) (both three-gene families in Arabidopsis) represent new effectors specific to plants and certain algal species. The evolutionary history of these genes in autotrophic eukaryotes remains elusive, making it an ongoing area of research. Analyses of potential protein-protein and co-occurrence interactions, informed by gene network patterns using the STRING database, in Arabidopsis thaliana and Chlamydomonas reinhardtii unveil intricate gene associations with ACCase, suggesting a complex interplay between FA synthesis and other cellular processes. Among both species, a higher number of co-expressed genes was identified in Arabidopsis, indicating a wider potential regulatory network of ACCase in plants. This review investigates the extent to which these genes arose in autotrophic eukaryotes and provides insights into their evolutionary trajectory. This article is part of the theme issue 'The evolution of plant metabolism'.
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Affiliation(s)
- Ana Caroline Conrado
- Division of Biochemistry and Interdisciplinary Plant Grou, C.S. Bond Life Sciences Center, University of Missouri , Columbia, MO 65211, USA
| | - Gabriel Lemes Jorge
- Division of Biochemistry and Interdisciplinary Plant Grou, C.S. Bond Life Sciences Center, University of Missouri , Columbia, MO 65211, USA
| | - R S P Rao
- Center for Bioinformatics, NITTE University Centre , Mangaluru 575018, India
| | - Chunhui Xu
- Institute for Data Science and Informatics, C.S. Bond Life Sciences Center, University of Missouri , Columbia, MO 65211, USA
| | - Dong Xu
- Department of Electrical Engineering and Computer Science, Institute for Data Science and Informatics, C.S. Bond Life Sciences Center, University of Missouri , Columbia, MO 65211, USA
| | - Yonghua Li-Beisson
- Aix Marseille Univ, CEA, CNRS, BIAM, Institut de Biosciences et Biotechnologies Aix-Marseille,Aix Marseille Univ, CEA Cadarache , Saint Paul-Lez-Durance 13108, France
| | - Jay J Thelen
- Division of Biochemistry and Interdisciplinary Plant Grou, C.S. Bond Life Sciences Center, University of Missouri , Columbia, MO 65211, USA
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2
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Fan J, Sah SK, Lemes Jorge G, Blanford J, Xie D, Yu L, Thelen J, Shanklin J, Xu C. Arabidopsis trigalactosyldiacylglycerol1 mutants reveal a critical role for phosphtidylcholine remodeling in lipid homeostasis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024. [PMID: 39276345 DOI: 10.1111/tpj.17020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 08/08/2024] [Accepted: 08/27/2024] [Indexed: 09/17/2024]
Abstract
Lipid remodeling plays a critical role in plant response to abiotic stress and metabolic perturbations. Key steps in this process involve modifications of phosphatidylcholine (PC) acyl chains mediated by lysophosphatidylcholine: acyl-CoA acyltransferases (LPCATs) and phosphatidylcholine: diacylglycerol cholinephosphotransferase (ROD1). To assess their importance in lipid homeostasis, we took advantage of the trigalactosyldiacylglycerol1 (tgd1) mutant that exhibits marked increases in fatty acid synthesis and fatty acid flux through PC due to a block in inter-organelle lipid trafficking. Here, we showed that the increased fatty acid synthesis in tgd1 is due to posttranslational activation of the plastidic acetyl-coenzyme A carboxylase. Genetic analysis showed that knockout of LPCAT1 and 2 resulted in a lethal phenotype in tgd1. In addition, plants homozygous for lpcat2 and heterozygous for lpcat1 in the tgd1 background showed reduced levels of PC and triacylglycerols (TAG) and alterations in their fatty acid profiles. We further showed that disruption of ROD1 in tgd1 resulted in changes in fatty acid composition of PC and TAG, decreased leaf TAG content and reduced seedling growth. Together, our results reveal a critical role of LPCATs and ROD1 in maintaining cellular lipid homeostasis under conditions, in which fatty acid production largely exceeds the cellular demand for membrane lipid synthesis.
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Affiliation(s)
- Jilian Fan
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Saroj Kumar Sah
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Gabriel Lemes Jorge
- Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri-Columbia, 1201 E Rollins, Columbia, Missouri, 65211, USA
| | - Jantana Blanford
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Dongling Xie
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Linhui Yu
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Jay Thelen
- Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri-Columbia, 1201 E Rollins, Columbia, Missouri, 65211, USA
| | - John Shanklin
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Changcheng Xu
- Biology Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
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3
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Clews AC, Ulch BA, Jesionowska M, Hong J, Mullen RT, Xu Y. Variety of Plant Oils: Species-Specific Lipid Biosynthesis. PLANT & CELL PHYSIOLOGY 2024; 65:845-862. [PMID: 37971406 DOI: 10.1093/pcp/pcad147] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/03/2023] [Accepted: 11/15/2023] [Indexed: 11/19/2023]
Abstract
Plant oils represent a large group of neutral lipids with important applications in food, feed and oleochemical industries. Most plants accumulate oils in the form of triacylglycerol within seeds and their surrounding tissues, which comprises three fatty acids attached to a glycerol backbone. Different plant species accumulate unique fatty acids in their oils, serving a range of applications in pharmaceuticals and oleochemicals. To enable the production of these distinctive oils, select plant species have adapted specialized oil metabolism pathways, involving differential gene co-expression networks and structurally divergent enzymes/proteins. Here, we summarize some of the recent advances in our understanding of oil biosynthesis in plants. We compare expression patterns of oil metabolism genes from representative species, including Arabidopsis thaliana, Ricinus communis (castor bean), Linum usitatissimum L. (flax) and Elaeis guineensis (oil palm) to showcase the co-expression networks of relevant genes for acyl metabolism. We also review several divergent enzymes/proteins associated with key catalytic steps of unique oil accumulation, including fatty acid desaturases, diacylglycerol acyltransferases and oleosins, highlighting their structural features and preference toward unique lipid substrates. Lastly, we briefly discuss protein interactomes and substrate channeling for oil biosynthesis and the complex regulation of these processes.
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Affiliation(s)
- Alyssa C Clews
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Brandon A Ulch
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Monika Jesionowska
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Jun Hong
- Center for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
- Department of Genetics and Developmental Science, Joint International Research Laboratory of Metabolic and Developmental Sciences, State Key Laboratory of Hybrid Rice, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Robert T Mullen
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Yang Xu
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Chandrasekaran U, Park S, Kim K, Byeon S, Han AR, Lee YS, Oh NH, Chung H, Choe H, Kim HS. Energy deprivation affects nitrogen assimilation and fatty acid biosynthesis leading to leaf chlorosis under waterlogging stress in the endangered Abies koreana. TREE PHYSIOLOGY 2024; 44:tpae055. [PMID: 38775218 DOI: 10.1093/treephys/tpae055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/15/2024] [Accepted: 05/21/2024] [Indexed: 06/21/2024]
Abstract
Energy deprivation triggers various physiological, biochemical and molecular changes in plants under abiotic stress. We investigated the oxidative damages in the high altitude grown conifer Korean fir (Abies koreana) exposed to waterlogging stress. Our experimental results showed that waterlogging stress led to leaf chlorosis, 35 days after treatment. A significant decrease in leaf fresh weight, chlorophyll and sugar content supported this phenotypic change. Biochemical analysis showed a significant increase in leaf proline, lipid peroxidase and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical content of waterlogged plants. To elucidate the molecular mechanisms, we conducted RNA-sequencing (RNA-seq) and de novo assembly. Using RNA-seq analysis approach and filtering (P < 0.05 and false discovery rate <0.001), we obtained 134 unigenes upregulated and 574 unigenes downregulated. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis placed the obtained differentially expressed unigenes in α-linoleic pathway, fatty acid degradation, glycosis, glycolipid metabolism and oligosaccharide biosynthesis process. Mapping of unigenes with Arabidopsis using basic local alignment search tool for nucleotides showed several critical genes in photosynthesis and carbon metabolism downregulated. Following this, we found the repression of multiple nitrogen (N) assimilation and nucleotide biosynthesis genes including purine metabolism. In addition, waterlogging stress reduced the levels of polyunsaturated fatty acids with a concomitant increase only in myristic acid. Together, our results indicate that the prolonged snowmelt may cause inability of A. koreana seedlings to lead the photosynthesis normally due to the lack of root intercellular oxygen and emphasizes a detrimental effect on the N metabolic pathway, compromising this endangered tree's ability to be fully functional under waterlogging stress.
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Affiliation(s)
- Umashankar Chandrasekaran
- Department of Agriculture, Forestry and Bioresources, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
| | - Sanghee Park
- Department of Agriculture, Forestry and Bioresources, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
| | - Kunhyo Kim
- Department of Agriculture, Forestry and Bioresources, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
| | - Siyeon Byeon
- Department of Agriculture, Forestry and Bioresources, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
| | - Ah Reum Han
- Division of Basic Research, National Institute of Ecology, 1210 Geumgang-ro, Seocheon-gun 33657, Republic of Korea
| | - Young-Sang Lee
- Division of Basic Research, National Institute of Ecology, 1210 Geumgang-ro, Seocheon-gun 33657, Republic of Korea
| | - Neung-Hwan Oh
- Department of Environmental Planning, Graduate School of Environmental Studies, Seoul National University, 1 Gwanak-gu, Seoul 08826, Republic of Korea
- Environmental Planning Institute, Seoul National University, 1 Gwanak-gu, Seoul 08826, Republic of Korea
| | - Haegeun Chung
- Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Hyeyeong Choe
- Department of Agriculture, Forestry and Bioresources, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
| | - Hyun Seok Kim
- Department of Agriculture, Forestry and Bioresources, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
- Interdisciplinary Program in Agricultural and Forest Meteorology, Seoul National University College of Agriculture and Life Sciences, 1 Gwanak-gu, Seoul 08826, Republic of Korea
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5
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Artins A, Martins MCM, Meyer C, Fernie AR, Caldana C. Sensing and regulation of C and N metabolism - novel features and mechanisms of the TOR and SnRK1 signaling pathways. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:1268-1280. [PMID: 38349940 DOI: 10.1111/tpj.16684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/25/2024] [Accepted: 02/02/2024] [Indexed: 02/15/2024]
Abstract
Carbon (C) and nitrogen (N) metabolisms are tightly integrated to allow proper plant growth and development. Photosynthesis is dependent on N invested in chlorophylls, enzymes, and structural components of the photosynthetic machinery, while N uptake and assimilation rely on ATP, reducing equivalents, and C-skeletons provided by photosynthesis. The direct connection between N availability and photosynthetic efficiency allows the synthesis of precursors for all metabolites and building blocks in plants. Thus, the capacity to sense and respond to sudden changes in C and N availability is crucial for plant survival and is mediated by complex yet efficient signaling pathways such as TARGET OF RAPAMYCIN (TOR) and SUCROSE-NON-FERMENTING-1-RELATED PROTEIN KINASE 1 (SnRK1). In this review, we present recent advances in mechanisms involved in sensing C and N status as well as identifying current gaps in our understanding. We finally attempt to provide new perspectives and hypotheses on the interconnection of diverse signaling pathways that will allow us to understand the integration and orchestration of the major players governing the regulation of the CN balance.
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Affiliation(s)
- Anthony Artins
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Golm, Germany
| | - Marina C M Martins
- in Press - Scientific Consulting and Communication Services, 05089-030, São Paulo, São Paulo, Brazil
| | - Christian Meyer
- Institut Jean-Pierre Bourgin (IJPB), INRAE, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Golm, Germany
| | - Camila Caldana
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Golm, Germany
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Zhang S, Wu S, Hou Q, Zhao J, Fang C, An X, Wan X. Fatty acid de novo biosynthesis in plastids: Key enzymes and their critical roles for male reproduction and other processes in plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 210:108654. [PMID: 38663264 DOI: 10.1016/j.plaphy.2024.108654] [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: 10/12/2023] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 05/12/2024]
Abstract
Fatty acid de novo biosynthesis in plant plastids is initiated from acetyl-CoA and catalyzed by a series of enzymes, which is required for the vegetative growth, reproductive growth, seed development, stress response, chloroplast development and other biological processes. In this review, we systematically summarized the fatty acid de novo biosynthesis-related genes/enzymes and their critical roles in various plant developmental processes. Based on bioinformatic analysis, we identified fatty acid synthase encoding genes and predicted their potential functions in maize growth and development, especially in anther and pollen development. Finally, we highlighted the potential applications of these fatty acid synthases in male-sterility hybrid breeding, seed oil content improvement, herbicide and abiotic stress resistance, which provides new insights into future molecular crop breeding.
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Affiliation(s)
- Simiao Zhang
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China
| | - Suowei Wu
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding, Beijing Solidwill Sci-Tech Co. Ltd., Beijing, 100192, China; Shandong Shouxin Seed Sci-Tech Co. Ltd., Zhucheng City, Shandong Province, 262200, China
| | - Quancan Hou
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China
| | - Junfeng Zhao
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China
| | - Chaowei Fang
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xueli An
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding, Beijing Solidwill Sci-Tech Co. Ltd., Beijing, 100192, China
| | - Xiangyuan Wan
- Research Institute of Biology and Agriculture, Zhongzhi International Institute of Agricultural Biosciences, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Engineering Laboratory of Main Crop Bio-Tech Breeding, Beijing Solidwill Sci-Tech Co. Ltd., Beijing, 100192, China.
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7
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Ensinck D, Gerhardt ECM, Rollan L, Huergo LF, Gramajo H, Diacovich L. The PII protein interacts with the Amt ammonium transport and modulates nitrate/nitrite assimilation in mycobacteria. Front Microbiol 2024; 15:1366111. [PMID: 38591044 PMCID: PMC11001197 DOI: 10.3389/fmicb.2024.1366111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 03/04/2024] [Indexed: 04/10/2024] Open
Abstract
PII proteins are signal transduction proteins that belong to a widely distributed family of proteins involved in the modulation of different metabolisms in bacteria. These proteins are homotrimers carrying a flexible loop, named T-loop, which changes its conformation due to the recognition of diverse key metabolites, ADP, ATP, and 2-oxoglutarate. PII proteins interact with different partners to primarily regulate a set of nitrogen pathways. In some organisms, PII proteins can also control carbon metabolism by interacting with the biotin carboxyl carrier protein (BCCP), a key component of the acetyl-CoA carboxylase (ACC) enzyme complex, inhibiting its activity with the consequent reduction of fatty acid biosynthesis. Most bacteria contain at least two PII proteins, named GlnB and GlnK, with different regulatory roles. In mycobacteria, only one PII protein was identified, and the three-dimensional structure was solved, however, its physiological role is unknown. In this study we purified the Mycobacterium tuberculosis (M. tb) PII protein, named GlnB, and showed that it weakly interacts with the AccA3 protein, the α subunit shared by the three different, and essential, Acyl-CoA carboxylase complexes (ACCase 4, 5, and 6) present in M. tb. A M. smegmatis deletion mutant, ∆MsPII, exhibited a growth deficiency on nitrate and nitrite as unique nitrogen sources, and accumulated nitrite in the culture supernatant. In addition, M. tb PII protein was able to interact with the C-terminal domain of the ammonium transporter Amt establishing the ancestral role for this PII protein as a GlnK functioning protein.
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Affiliation(s)
- Delfina Ensinck
- Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Edileusa C. M. Gerhardt
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Lara Rollan
- Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Luciano F. Huergo
- Setor Litoral, Federal University of Paraná, Universidade Federal do Paraná (UFPR), Matinhos, Paraná, Brazil
- Graduated Program in Sciences-Biochemistry, Universidade Federal do Paraná (UFPR), Curitiba, Paraná, Brazil
| | - Hugo Gramajo
- Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Lautaro Diacovich
- Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
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Lee KT, Liao HS, Hsieh MH. Glutamine Metabolism, Sensing and Signaling in Plants. PLANT & CELL PHYSIOLOGY 2023; 64:1466-1481. [PMID: 37243703 DOI: 10.1093/pcp/pcad054] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/23/2023] [Accepted: 05/24/2023] [Indexed: 05/29/2023]
Abstract
Glutamine (Gln) is the first amino acid synthesized in nitrogen (N) assimilation in plants. Gln synthetase (GS), converting glutamate (Glu) and NH4+ into Gln at the expense of ATP, is one of the oldest enzymes in all life domains. Plants have multiple GS isoenzymes that work individually or cooperatively to ensure that the Gln supply is sufficient for plant growth and development under various conditions. Gln is a building block for protein synthesis and an N-donor for the biosynthesis of amino acids, nucleic acids, amino sugars and vitamin B coenzymes. Most reactions using Gln as an N-donor are catalyzed by Gln amidotransferase (GAT) that hydrolyzes Gln to Glu and transfers the amido group of Gln to an acceptor substrate. Several GAT domain-containing proteins of unknown function in the reference plant Arabidopsis thaliana suggest that some metabolic fates of Gln have yet to be identified in plants. In addition to metabolism, Gln signaling has emerged in recent years. The N regulatory protein PII senses Gln to regulate arginine biosynthesis in plants. Gln promotes somatic embryogenesis and shoot organogenesis with unknown mechanisms. Exogenous Gln has been implicated in activating stress and defense responses in plants. Likely, Gln signaling is responsible for some of the new Gln functions in plants.
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Affiliation(s)
- Kim-Teng Lee
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
- Molecular and Biological Agricultural Sciences, The Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
- Biotechnology Center, National Chung-Hsing University, Taichung 40227, Taiwan
| | - Hong-Sheng Liao
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Ming-Hsiun Hsieh
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
- Molecular and Biological Agricultural Sciences, The Taiwan International Graduate Program, Academia Sinica, Taipei 11529, Taiwan
- Biotechnology Center, National Chung-Hsing University, Taichung 40227, Taiwan
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9
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Xu Y, Singer SD, Chen G. Protein interactomes for plant lipid biosynthesis and their biotechnological applications. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:1734-1744. [PMID: 36762506 PMCID: PMC10440990 DOI: 10.1111/pbi.14027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/18/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
Plant lipids have essential biological roles in plant development and stress responses through their functions in cell membrane formation, energy storage and signalling. Vegetable oil, which is composed mainly of the storage lipid triacylglycerol, also has important applications in food, biofuel and oleochemical industries. Lipid biosynthesis occurs in multiple subcellular compartments and involves the coordinated action of various pathways. Although biochemical and molecular biology research over the last few decades has identified many proteins associated with lipid metabolism, our current understanding of the dynamic protein interactomes involved in lipid biosynthesis, modification and channelling is limited. This review examines advances in the identification and characterization of protein interactomes involved in plant lipid biosynthesis, with a focus on protein complexes consisting of different subunits for sequential reactions such as those in fatty acid biosynthesis and modification, as well as transient or dynamic interactomes formed from enzymes in cooperative pathways such as assemblies of membrane-bound enzymes for triacylglycerol biosynthesis. We also showcase a selection of representative protein interactome structures predicted using AlphaFold2, and discuss current and prospective strategies involving the use of interactome knowledge in plant lipid biotechnology. Finally, unresolved questions in this research area and possible approaches to address them are also discussed.
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Affiliation(s)
- Yang Xu
- Department of Molecular and Cellular BiologyUniversity of GuelphGuelphOntarioCanada
| | - Stacy D. Singer
- Agriculture and Agri‐Food Canada, Lethbridge Research and Development CentreLethbridgeAlbertaCanada
| | - Guanqun Chen
- Department of Agricultural, Food and Nutritional ScienceUniversity of AlbertaEdmontonAlbertaCanada
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10
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Shen F, Qin Y, Wang R, Huang X, Wang Y, Gao T, He J, Zhou Y, Jiao Y, Wei J, Li L, Yang X. Comparative genomics reveals a unique nitrogen-carbon balance system in Asteraceae. Nat Commun 2023; 14:4334. [PMID: 37474573 PMCID: PMC10359422 DOI: 10.1038/s41467-023-40002-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 07/07/2023] [Indexed: 07/22/2023] Open
Abstract
The Asteraceae (daisy family) is one of the largest families of plants. The genetic basis for its high biodiversity and excellent adaptability has not been elucidated. Here, we compare the genomes of 29 terrestrial plant species, including two de novo chromosome-scale genome assemblies for stem lettuce, a member of Asteraceae, and Scaevola taccada, a member of Goodeniaceae that is one of the closest outgroups of Asteraceae. We show that Asteraceae originated ~80 million years ago and experienced repeated paleopolyploidization. PII, the universal regulator of nitrogen-carbon (N-C) assimilation present in almost all domains of life, has conspicuously lost across Asteraceae. Meanwhile, Asteraceae has stepwise upgraded the N-C balance system via paleopolyploidization and tandem duplications of key metabolic genes, resulting in enhanced nitrogen uptake and fatty acid biosynthesis. In addition to suggesting a molecular basis for their ecological success, the unique N-C balance system reported for Asteraceae offers a potential crop improvement strategy.
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Affiliation(s)
- Fei Shen
- Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, 100097, Beijing, China
| | - Yajuan Qin
- Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, 100097, Beijing, China
| | - Rui Wang
- Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, College of Horticulture, China Agricultural University, 100193, Beijing, China
| | - Xin Huang
- Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, 100097, Beijing, China
| | - Ying Wang
- Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, 100097, Beijing, China
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, 100871, Beijing, China
| | - Tiangang Gao
- State Key Laboratory of Evolutionary and Systematic Botany, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
| | - Junna He
- Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, College of Horticulture, China Agricultural University, 100193, Beijing, China
| | - Yue Zhou
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, 100871, Beijing, China
| | - Yuannian Jiao
- State Key Laboratory of Evolutionary and Systematic Botany, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China
| | - Jianhua Wei
- Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, 100097, Beijing, China.
| | - Lei Li
- State Key Laboratory of Protein and Plant Gene Research, School of Advanced Agricultural Sciences, Peking University, 100871, Beijing, China.
| | - Xiaozeng Yang
- Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology, Institute of Biotechnology, Beijing Academy of Agriculture and Forestry Sciences, 100097, Beijing, China.
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11
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Selvan ST, Chandrasekaran R, Muthusamy S, Ramamurthy D. Eco-friendly approach for tannery effluent treatment and CO 2 sequestration using unicellular green oleaginous microalga Tetradesmus obliquus TS03. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:48138-48156. [PMID: 36752925 DOI: 10.1007/s11356-023-25703-4] [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: 11/15/2022] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
The present study explored the process of bioremediation, sequestration of carbon dioxide, and biofuel production using multifarious potent freshwater microalgae Tetradesmus obliquus TS03. The heavy metals were reduced, viz., 8.34 mg of cadmium (95.13%), 4.56 mg of chromium (97.28%), 1.34 mg of copper (98.67%), 1.24 mg of cobalt (98.19%), 1.93 mg of lead (96.72%), 2.31 mg of nickel (97.14%), and 2.23 mgL-1 of zinc (96.59%) using photobioreactor microalgal treatment method. The heavy metal biosorption capacity rate (qmax) was 98.90% determined by the Langmuir and Freundlich isotherm kinetics model at 10 days of effluent treatment using Tetradesmus obliquus TS03. The microalgae T. obliquus TS03 utilized 98.34% of carbon dioxide (CO2) enhanced by acetyl CoA carboxylase and RuBisCO enzymes. The biodiesel was extracted from microalga and identified 32 fatty acid methyl ester major compounds viz., tetradecanoate methyl ester, hexadecanoic acid methyl ester, tridecanoic acid methyl ester, heptadecatrienoic acid methyl ester, octadecanoic acid methyl ester, eicosanoic acid methyl ester, pentadecanoic acid methyl ester, and cis-methylicosanoate using gas mass chromatography (GCMS). The biodiesel functional groups were identified, viz., amides, phenols, alcohols, alkynes, carboxylic acids, carbonyls, and ketones groups using Fourier transformation infrared (FTIR). The bioethanol was identified using high-performance liquid chromatography (HPLC) and determined the peak presented at RT of 4.35 min (75,693.1046 µV s-1).
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Affiliation(s)
- Silambarasan Tamil Selvan
- Department of Microbiology, School of Allied Health Sciences, VIMS Hospital Campus, Vinayaka Missions Research Foundation (DU), Salem, 636308, Tamil Nadu, India.
| | - Ravikumar Chandrasekaran
- Department of Basic Engineering Sciences, TPEVR Government Polytechnic College, Vellore, 632002, Tamil Nadu, India
| | - Sanjivkumar Muthusamy
- Department of Microbiology, K.R. College of Arts & Science, K.R. Nagar, Kovilpatti, 628503, Tamil Nadu, India
| | - Dhandapani Ramamurthy
- Department of Microbiology, School of Biosciences, Periyar University, Salem, 636011, Tamil Nadu, India
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12
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Babele PK, Srivastava A, Selim KA, Kumar A. Millet-inspired systems metabolic engineering of NUE in crops. Trends Biotechnol 2022; 41:701-713. [PMID: 36566140 DOI: 10.1016/j.tibtech.2022.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 10/20/2022] [Accepted: 10/27/2022] [Indexed: 12/24/2022]
Abstract
The use of nitrogen (N) fertilizers in agriculture has a great ability to increase crop productivity. However, their excessive use has detrimental effects on the environment. Therefore, it is necessary to develop crop varieties with improved nitrogen use efficiency (NUE) that require less N but have substantial yields. Orphan crops such as millets are cultivated in limited regions and are well adapted to lower input conditions. Therefore, they serve as a rich source of beneficial traits that can be transferred into major crops to improve their NUE. This review highlights the tremendous potential of systems biology to unravel the enzymes and pathways involved in the N metabolism of millets, which can open new possibilities to generate transgenic crops with improved NUE.
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Affiliation(s)
- Piyoosh K Babele
- Rani Lakshmi Bai Central Agricultural University, Jhansi 284003, Uttar Pradesh, India.
| | - Amit Srivastava
- University of Jyväskylä, Nanoscience Centre, Department of Biological and Environmental Science, 40014 Jyväskylä, Finland
| | - Khaled A Selim
- Organismic Interactions Department, Interfaculty Institute for Microbiology and Infection Medicine, Cluster of Excellence 'Controlling Microbes to Fight Infections', Tübingen University, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Anil Kumar
- Rani Lakshmi Bai Central Agricultural University, Jhansi 284003, Uttar Pradesh, India
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13
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Iskhakova ZI, Zhuravleva DE, Heim C, Hartmann MD, Laykov AV, Forchhammer K, Kayumov AR. PotN represents a novel energy‐state sensing PII subfamily, occurring in firmicutes. FEBS J 2022; 289:5305-5321. [DOI: 10.1111/febs.16431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 02/19/2022] [Accepted: 03/10/2022] [Indexed: 01/19/2023]
Affiliation(s)
| | | | - Christopher Heim
- Department of Protein Evolution Max Planck Institute for Developmental Biology Tübingen Germany
| | - Marcus D. Hartmann
- Department of Protein Evolution Max Planck Institute for Developmental Biology Tübingen Germany
| | | | - Karl Forchhammer
- Institut für Mikrobiologie Eberhard‐Karls‐Universität Tübingen Germany
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14
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Wang M, Garneau MG, Poudel AN, Lamm D, Koo AJ, Bates PD, Thelen JJ. Overexpression of pea α-carboxyltransferase in Arabidopsis and camelina increases fatty acid synthesis leading to improved seed oil content. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 110:1035-1046. [PMID: 35220631 DOI: 10.1111/tpj.15721] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/11/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
SUMMARYHeteromeric acetyl‐CoA carboxylase (htACCase) catalyzes the committed step of de novo fatty acid biosynthesis in most plant plastids. Plant htACCase is comprised of four subunits: α‐ and β‐carboxyltransferase (α‐ and β‐CT), biotin carboxylase, and biotin carboxyl carrier protein. Based on in vivo absolute quantification of htACCase subunits, α‐CT is 3‐ to 10‐fold less abundant than its partner subunit β‐CT in developing Arabidopsis seeds [Wilson and Thelen, J. Proteome Res., 2018, 17 (5)]. To test the hypothesis that low expression of α‐CT limits htACCase activity and flux through fatty acid synthesis in planta, we overexpressed Pisum sativum α‐CT, either with or without its C‐terminal non‐catalytic domain, in both Arabidopsis thaliana and Camelina sativa. First‐generation Arabidopsis seed of 35S::Ps α‐CT (n = 25) and 35S::Ps α‐CTΔ406‐875 (n = 47) were on average 14% higher in oil content (% dry weight) than wild type co‐cultivated in a growth chamber. First‐generation camelina seed showed an average 8% increase compared to co‐cultivated wild type. Biochemical analyses confirmed the accumulation of Ps α‐CT and Ps α‐CTΔ406‐875 protein and higher htACCase activity in overexpression lines during early seed development. Overexpressed Ps α‐CT co‐migrated with native At β‐CT during anion exchange chromatography, indicating co‐association. By successfully increasing seed oil content upon heterologous overexpression of α‐CT, we demonstrate how absolute quantitation of in vivo protein complex stoichiometry can be used to guide rational metabolic engineering.
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Affiliation(s)
- Minmin Wang
- Department of Biochemistry, University of Missouri, Columbia, Missouri, 65211, USA
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, 65211, USA
| | - Matthew G Garneau
- Institute of Biological Chemistry, Washington State University, Pullman, Washington, DC, 99164, USA
| | - Arati N Poudel
- Department of Biochemistry, University of Missouri, Columbia, Missouri, 65211, USA
| | - Daniel Lamm
- Department of Biochemistry, University of Missouri, Columbia, Missouri, 65211, USA
| | - Abraham J Koo
- Department of Biochemistry, University of Missouri, Columbia, Missouri, 65211, USA
| | - Philip D Bates
- Institute of Biological Chemistry, Washington State University, Pullman, Washington, DC, 99164, USA
| | - Jay J Thelen
- Department of Biochemistry, University of Missouri, Columbia, Missouri, 65211, USA
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri, 65211, USA
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15
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Fus3, as a Critical Kinase in MAPK Cascade, Regulates Aflatoxin Biosynthesis by Controlling the Substrate Supply in Aspergillus flavus, Rather than the Cluster Genes Modulation. Microbiol Spectr 2022; 10:e0126921. [PMID: 35107358 PMCID: PMC8809346 DOI: 10.1128/spectrum.01269-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Fus3-MAP kinase module is a conserved phosphorylation signal system in eukaryotes that responds to environmental stress and transduction of external signals from the outer membrane to the nucleus. Aspergillus flavus can produce aflatoxins (AF), which seriously threaten human and animal health. In this study, we determined the functions of Fus3, confirmed Ste50-Ste11-Ste7-Fus3 protein interactions and phosphorylation, and explored the possible phosphorylation motifs and potential targets of Fus3. The regulatory mechanism of Fus3 on the biosynthesis of AF was partly revealed in this study. AF production was downregulated in Δfus3, but the transcriptional expression of most AF cluster genes was upregulated. It is notable that the levels of acetyl-CoA and malonyl-CoA, the substrates of AF, were significantly decreased in fus3 defective strains. Genes involved in acetyl-CoA and malonyl-CoA biosynthesis were significantly downregulated at transcriptional or phosphorylation levels. Specifically, AccA might be a direct target of Fus3, which led to acetyl-CoA carboxylase activities were decreased in null-deletion and site mutagenesis strains. The results concluded that Fus3 could regulate the expression of acetyl-CoA and malonyl-CoA biosynthetic genes directly or indirectly, and then affect the AF production that relies on the regulation of AF substrate rather than the modulation of AF cluster genes. IMPORTANCEAspergillus flavus is an important saprophytic fungus that produces aflatoxins (AF), which threaten food and feed safety. MAP (mitogen-activated protein) kanases are essential for fungal adaptation to diverse environments. Fus3, as the terminal kinase of a MAPK cascade, interacts with other MAPK modules and phosphorylates downstream targets. We provide evidence that Fus3 could affect AF biosynthesis by regulating the production of acetyl-CoA and malonyl-CoA, but this does not depend on the regulation of AF biosynthetic genes. Our results partly reveal the regulatory mechanism of Fus3 on AF biosynthesis and provide a novel AF modulation pattern, which may contribute to the discovery of new strategies in controlling A. flavus and AF contamination.
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16
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New views on PII signaling: from nitrogen sensing to global metabolic control. Trends Microbiol 2022; 30:722-735. [DOI: 10.1016/j.tim.2021.12.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 11/20/2022]
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17
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Arabidopsis PII Proteins Form Characteristic Foci in Chloroplasts Indicating Novel Properties in Protein Interaction and Degradation. Int J Mol Sci 2021; 22:ijms222312666. [PMID: 34884470 PMCID: PMC8657445 DOI: 10.3390/ijms222312666] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 11/16/2021] [Accepted: 11/21/2021] [Indexed: 11/16/2022] Open
Abstract
The PII protein is an evolutionary, highly conserved regulatory protein found in both bacteria and higher plants. In bacteria, it modulates the activity of several enzymes, transporters, and regulatory factors by interacting with them and thereby regulating important metabolic hubs, such as carbon/nitrogen homeostasis. More than two decades ago, the PII protein was characterized for the first time in plants, but its physiological role is still not sufficiently resolved. To gain more insights into the function of this protein, we investigated the interaction behavior of AtPII with candidate proteins by BiFC and FRET/FLIM in planta and with GFP/RFP traps in vitro. In the course of these studies, we found that AtPII interacts in chloroplasts with itself as well as with known interactors such as N-acetyl-L-glutamate kinase (NAGK) in dot-like aggregates, which we named PII foci. In these novel protein aggregates, AtPII also interacts with yet unknown partners, which are known to be involved in plastidic protein degradation. Further studies revealed that the C-terminal component of AtPII is crucial for the formation of PII foci. Altogether, the discovery and description of PII foci indicate a novel mode of interaction between PII proteins and other proteins in plants. These findings may represent a new starting point for the elucidation of physiological functions of PII proteins in plants.
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18
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Condori-Apfata JA, Batista-Silva W, Medeiros DB, Vargas JR, Valente LML, Pérez-Díaz JL, Fernie AR, Araújo WL, Nunes-Nesi A. Downregulation of the E2 Subunit of 2-Oxoglutarate Dehydrogenase Modulates Plant Growth by Impacting Carbon-Nitrogen Metabolism in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2021; 62:798-814. [PMID: 33693904 PMCID: PMC8484937 DOI: 10.1093/pcp/pcab036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 02/28/2021] [Accepted: 04/16/2021] [Indexed: 05/04/2023]
Abstract
In Arabidopsis thaliana, two genes encode the E2 subunit of the 2-oxoglutarate dehydrogenase (2-OGDH), a multimeric complex composed of three subunits. To functionally characterize the isoforms of E2 subunit, we isolated Arabidopsis mutant lines for each gene encoding the E2 subunit and performed a detailed molecular and physiological characterization of the plants under controlled growth conditions. The functional lack of expression of E2 subunit isoforms of 2-OGDH increased plant growth, reduced dark respiration and altered carbohydrate metabolism without changes in the photosynthetic rate. Interestingly, plants from e2-ogdh lines also exhibited reduced seed weight without alterations in total seed number. We additionally observed that downregulation of 2-OGDH activity led to minor changes in the levels of tricarboxylic acid cycle intermediates without clear correlation with the reduced expression of specific E2-OGDH isoforms. Furthermore, the e2-ogdh mutant lines exhibited a reduction by up to 25% in the leaf total amino acids without consistent changes in the amino acid profile. Taken together, our results indicate that the two isoforms of E2 subunit play a similar role in carbon-nitrogen metabolism, in plant growth and in seed weight.
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Affiliation(s)
- Jorge A Condori-Apfata
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Willian Batista-Silva
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - David Barbosa Medeiros
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, Potsdam Golm 14476, Germany
| | - Jonas Rafael Vargas
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Luiz M Lopes Valente
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Jorge Luis Pérez-Díaz
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Alisdair R Fernie
- * Corresponding authors: Alisdair R. Fernie, E-mail, ; Adriano Nunes-Nesi, E-mail,
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Adriano Nunes-Nesi
- * Corresponding authors: Alisdair R. Fernie, E-mail, ; Adriano Nunes-Nesi, E-mail,
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Sakamoto T, Takatani N, Sonoike K, Jimbo H, Nishiyama Y, Omata T. Dissection of the Mechanisms of Growth Inhibition Resulting from Loss of the PII Protein in the Cyanobacterium Synechococcus elongatus PCC 7942. PLANT & CELL PHYSIOLOGY 2021; 62:721-731. [PMID: 33650637 PMCID: PMC8474142 DOI: 10.1093/pcp/pcab030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/18/2021] [Indexed: 05/08/2023]
Abstract
In cyanobacteria, the PII protein (the glnB gene product) regulates a number of proteins involved in nitrogen assimilation including PipX, the coactivator of the global nitrogen regulator protein NtcA. In Synechococcus elongatus PCC 7942, construction of a PII-less mutant retaining the wild-type pipX gene is difficult because of the toxicity of uncontrolled action of PipX and the other defect(s) resulting from the loss of PIIper se, but the nature of the PipX toxicity and the PipX-independent defect(s) remains unclear. Characterization of a PipX-less glnB mutant (PD4) in this study showed that the loss of PII increases the sensitivity of PSII to ammonium. Ammonium was shown to stimulate the formation of reactive oxygen species in the mutant cells. The ammonium-sensitive growth phenotype of PD4 was rescued by the addition of an antioxidant α-tocopherol, confirming that photo-oxidative damage was the major cause of the growth defect. A targeted PII mutant retaining wild-type pipX was successfully constructed from the wild-type S. elongatus strain (SPc) in the presence of α-tocopherol. The resulting mutant (PD1X) showed an unusual chlorophyll fluorescence profile, indicating extremely slow reduction and re-oxidation of QA, which was not observed in mutants defective in both glnB and pipX. These results showed that the aberrant action of uncontrolled PipX resulted in an impairment of the electron transport reactions in both the reducing and oxidizing sides of QA.
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Affiliation(s)
- Takayuki Sakamoto
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
| | - Nobuyuki Takatani
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan
| | - Kintake Sonoike
- Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, 162-8480 Japan
| | - Haruhiko Jimbo
- Graduate School of Science and Engineering, Saitama University, Saitama, 338-8570 Japan
- Graduate School of Arts and Sciences, University of Tokyo,Tokyo 153-8902Japan
| | - Yoshitaka Nishiyama
- Graduate School of Science and Engineering, Saitama University, Saitama, 338-8570 Japan
| | - Tatsuo Omata
- * Corresponding author: E-mail, ; Fax, +81-52-789-4107
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20
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The Classical, Yet Controversial, First Enzyme of Lipid Synthesis: Escherichia coli Acetyl-CoA Carboxylase. Microbiol Mol Biol Rev 2021; 85:e0003221. [PMID: 34132100 DOI: 10.1128/mmbr.00032-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Escherichia coli acetyl-CoA carboxylase (ACC), the enzyme responsible for synthesis of malonyl-CoA, the building block of fatty acid synthesis, is the paradigm bacterial ACC. Many reports on the structures and stoichiometry of the four subunits comprising the active enzyme as well as on regulation of ACC activity and expression have appeared in the almost 20 years since this subject was last reviewed. This review seeks to update and expand on these reports.
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21
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Wang P, Wang X, Yin Y, He M, Tan W, Gao W, Wen J. Increasing the Ascomycin Yield by Relieving the Inhibition of Acetyl/Propionyl-CoA Carboxylase by the Signal Transduction Protein GlnB. Front Microbiol 2021; 12:684193. [PMID: 34122395 PMCID: PMC8187598 DOI: 10.3389/fmicb.2021.684193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 04/29/2021] [Indexed: 11/13/2022] Open
Abstract
Ascomycin (FK520) is a multifunctional antibiotic produced by Streptomyces hygroscopicus var. ascomyceticus. In this study, we demonstrated that the inactivation of GlnB, a signal transduction protein belonging to the PII family, can increase the production of ascomycin by strengthening the supply of the precursors malonyl-CoA and methylmalonyl-CoA, which are produced by acetyl-CoA carboxylase and propionyl-CoA carboxylase, respectively. Bioinformatics analysis showed that Streptomyces hygroscopicus var. ascomyceticus contains two PII family signal transduction proteins, GlnB and GlnK. Protein co-precipitation experiments demonstrated that GlnB protein could bind to the α subunit of acetyl-CoA carboxylase, and this binding could be disassociated by a sufficient concentration of 2-oxoglutarate. Coupled enzyme activity assays further revealed that the interaction between GlnB protein and the α subunit inhibited both the activity of acetyl-CoA carboxylase and propionyl-CoA carboxylase, and this inhibition could be relieved by 2-oxoglutarate in a concentration-dependent manner. Because GlnK protein can act redundantly to maintain metabolic homeostasis under the control of the global nitrogen regulator GlnR, the deletion of GlnB protein enhanced the supply of malonyl-CoA and methylmalonyl-CoA by restoring the activity of acetyl-CoA carboxylase and propionyl-CoA carboxylase, thereby improving the production of ascomycin to 390 ± 10 mg/L. On this basis, the co-overexpression of the β and ε subunits of propionyl-CoA carboxylase further increased the ascomycin yield to 550 ± 20 mg/L, which was 1.9-fold higher than that of the parent strain FS35 (287 ± 9 mg/L). Taken together, this study provides a novel strategy to increase the production of ascomycin, providing a reference for improving the yield of other antibiotics.
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Affiliation(s)
- Pan Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Xin Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Ying Yin
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Mingliang He
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Wei Tan
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Wenting Gao
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Jianping Wen
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
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22
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Chen H, Wang Q. Regulatory mechanisms of lipid biosynthesis in microalgae. Biol Rev Camb Philos Soc 2021; 96:2373-2391. [PMID: 34101323 DOI: 10.1111/brv.12759] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 02/01/2023]
Abstract
Microalgal lipids are highly promising feedstocks for biofuel production. Microalgal lipids, especially triacylglycerol, and practical applications of these compounds have received increasing attention in recent years. For the commercial use of microalgal lipids to be feasible, many fundamental biological questions must be addressed based on detailed studies of algal biology, including how lipid biosynthesis occurs and is regulated. Here, we review the current understanding of microalgal lipid biosynthesis, with a focus on the underlying regulatory mechanisms. We also present possible solutions for overcoming various obstacles to understanding the basic biology of microalgal lipid biosynthesis and the practical application of microalgae-based lipids. This review will provide a theoretical reference for both algal researchers and decision makers regarding the future directions of microalgal research, particularly pertaining to microalgal-based lipid biosynthesis.
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Affiliation(s)
- Hui Chen
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
| | - Qiang Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China
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23
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Xu Y, Bonizzoni M. Discrimination and Quantitation of Biologically Relevant Carboxylate Anions Using A [Dye•PAMAM] Complex. SENSORS 2021; 21:s21113637. [PMID: 34073712 PMCID: PMC8197244 DOI: 10.3390/s21113637] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/17/2021] [Accepted: 05/20/2021] [Indexed: 12/01/2022]
Abstract
Carboxylate anions are analytical targets with environmental and biological relevance, whose detection is often challenging in aqueous solutions. We describe a method for discrimination and quantitation of carboxylates in water buffered to pH 7.4 based on their differential interaction with a supramolecular fluorescent sensor, self-assembled from readily available building blocks. A fifth-generation poly(amidoamine) dendrimer (PAMAM G5), bound to organic fluorophores (calcein or pyranine) through noncovalent interactions, forms a [dye•PAMAM] complex responsive to interaction with carboxylates. The observed changes in absorbance, and in fluorescence emission and anisotropy, were interpreted through linear discriminant analysis (LDA) and principal component analysis (PCA) to differentiate 10 structurally similar carboxylates with a limit of discrimination around 100 μM. The relationship between the analytes’ chemical structures and the system’s response was also elucidated. This insight allowed us to extend the system’s capabilities to the simultaneous identification of the nature and concentration of unknown analytes, with excellent structural identification results and good concentration recovery, an uncommon feat for a pattern-based sensing system.
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Affiliation(s)
- Yifei Xu
- Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, AL 35487, USA;
| | - Marco Bonizzoni
- Department of Chemistry and Biochemistry, The University of Alabama, Tuscaloosa, AL 35487, USA;
- Alabama Water Institute, The University of Alabama, Tuscaloosa, AL 35487, USA
- Correspondence:
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Yu XH, Cai Y, Keereetaweep J, Wei K, Chai J, Deng E, Liu H, Shanklin J. Biotin attachment domain-containing proteins mediate hydroxy fatty acid-dependent inhibition of acetyl CoA carboxylase. PLANT PHYSIOLOGY 2021; 185:892-901. [PMID: 33793910 PMCID: PMC8133645 DOI: 10.1093/plphys/kiaa109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 11/13/2020] [Indexed: 05/02/2023]
Abstract
Hundreds of naturally occurring specialized fatty acids (FAs) have potential as desirable chemical feedstocks if they could be produced at large scale by crop plants; however, transgenic expression of their biosynthetic genes has generally been accompanied by dramatic reductions in oil yield. For example, expression of castor (Ricinus communis) FA hydroxylase (FAH) in the Arabidopsis thaliana FA elongation mutant fae1 resulted in a 50% reduction of FA synthesis rate that was attributed to inhibition of acetyl-CoA carboxylase (ACCase) by an undefined mechanism. Here, we tested the hypothesis that the ricinoleic acid-dependent decrease in ACCase activity is mediated by biotin attachment domain-containing (BADC) proteins. BADCs are inactive homologs of biotin carboxy carrier protein that lack a biotin cofactor and can inhibit ACCase. Arabidopsis contains three BADC genes. To reduce expression levels of BADC1 and BADC3 in fae1/FAH plants, a homozygous badc1,3/fae1/FAH line was created. The rate of FA synthesis in badc1,3/fae1/FAH seeds doubled relative to fae1/FAH, restoring it to fae1 levels, increasing both native FA and HFA accumulation. Total FA per seed, seed oil content, and seed yield per plant all increased in badc1,3/fae1/FAH, to 5.8 µg, 37%, and 162 mg, respectively, relative to 4.9 µg, 33%, and 126 mg, respectively, for fae1/FAH. Transcript levels of FA synthesis-related genes, including those encoding ACCase subunits, did not significantly differ between badc1,3/fae1/FAH and fae1/FAH. These results demonstrate that BADC1 and BADC3 mediate ricinoleic acid-dependent inhibition of FA synthesis. We propose that BADC-mediated FAS inhibition as a general mechanism that limits FA accumulation in specialized FA-accumulating seeds.
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Affiliation(s)
- Xiao-Hong Yu
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Yuanheng Cai
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | | | - Kenneth Wei
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jin Chai
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Elen Deng
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Hui Liu
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - John Shanklin
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA
- Author for communication:
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Zhai Z, Keereetaweep J, Liu H, Feil R, Lunn JE, Shanklin J. Expression of a Bacterial Trehalose-6-phosphate Synthase otsA Increases Oil Accumulation in Plant Seeds and Vegetative Tissues. FRONTIERS IN PLANT SCIENCE 2021; 12:656962. [PMID: 33777087 PMCID: PMC7988188 DOI: 10.3389/fpls.2021.656962] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 02/18/2021] [Indexed: 05/03/2023]
Abstract
We previously demonstrated that exogenous trehalose 6-phosphate (T6P) treatment stabilized WRINKLED1 (WRI1), a master transcriptional regulator of fatty acid (FA) synthesis and increased total FA content in Brassica napus (B. napus) embryo suspension cell culture. Here, we explore Arabidopsis lines heterologously expressing the Escherichia coli T6P synthase (otsA) or T6P phosphatase (otsB) to refine our understanding regarding the role of T6P in regulating fatty acid synthesis both in seeds and vegetative tissues. Arabidopsis 35S:otsA transgenic seeds showed an increase of 13% in fatty acid content compared to those of wild type (WT), while seeds of 35:otsB transgenic seeds showed a reduction of 12% in fatty acid content compared to WT. Expression of otsB significantly reduced the level of WRI1 and expression of its target genes in developing seeds. Like Arabidopsis seeds constitutively expressing otsA, transient expression of otsA in Nicotiana benthamiana leaves resulted in strongly elevated levels of T6P. This was accompanied by an increase of 29% in de novo fatty acid synthesis rate, a 2.3-fold increase in triacylglycerol (TAG) and a 20% increase in total fatty acid content relative to empty vector (EV) controls. Taken together, these data support the heterologous expression of otsA as an approach to increasing TAG accumulation in plant seeds and vegetative tissues.
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Affiliation(s)
- Zhiyang Zhai
- Department of Biology, Brookhaven National Laboratory, Upton, NY, United States
| | | | - Hui Liu
- Department of Biology, Brookhaven National Laboratory, Upton, NY, United States
| | - Regina Feil
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - John E. Lunn
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - John Shanklin
- Department of Biology, Brookhaven National Laboratory, Upton, NY, United States
- *Correspondence: John Shanklin,
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Zhai Z, Keereetaweep J, Liu H, Xu C, Shanklin J. The Role of Sugar Signaling in Regulating Plant Fatty Acid Synthesis. FRONTIERS IN PLANT SCIENCE 2021; 12:643843. [PMID: 33828577 PMCID: PMC8020596 DOI: 10.3389/fpls.2021.643843] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/17/2021] [Indexed: 05/07/2023]
Abstract
Photosynthates such as glucose, sucrose, and some of their derivatives play dual roles as metabolic intermediates and signaling molecules that influence plant cell metabolism. Such sugars provide substrates for de novo fatty acid (FA) biosynthesis. However, compared with the well-defined examples of sugar signaling in starch and anthocyanin synthesis, until recently relatively little was known about the role of signaling in regulating FA and lipid biosynthesis. Recent research progress shows that trehalose 6-phosphate and 2-oxoglutarate (2-OG) play direct signaling roles in the regulation of FA biosynthesis by modulating transcription factor stability and enzymatic activities involved in FA biosynthesis. Specifically, mechanistic links between sucrose non-fermenting-1-related protein kinase 1 (SnRK1)-mediated trehalose 6-phosphate (T6P) sensing and its regulation by phosphorylation of WRI1 stability, diacylglycerol acyltransferase 1 (DGAT1) enzyme activity, and of 2-OG-mediated relief of inhibition of acetyl-CoA carboxylase (ACCase) activity by protein PII are exemplified in detail in this review.
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Docking of acetyl-CoA carboxylase to the plastid envelope membrane attenuates fatty acid production in plants. Nat Commun 2020; 11:6191. [PMID: 33273474 PMCID: PMC7712654 DOI: 10.1038/s41467-020-20014-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 11/09/2020] [Indexed: 11/12/2022] Open
Abstract
In plants, light-dependent activation of de novo fatty acid synthesis (FAS) is partially mediated by acetyl-CoA carboxylase (ACCase), the first committed step for this pathway. However, it is not fully understood how plants control light-dependent FAS regulation to meet the cellular demand for acyl chains. We report here the identification of a gene family encoding for three small plastidial proteins of the envelope membrane that interact with the α-carboxyltransferase (α-CT) subunit of ACCase and participate in an original mechanism restraining FAS in the light. Light enhances the interaction between carboxyltransferase interactors (CTIs) and α-CT, which in turn attenuates carbon flux into FAS. Knockouts for CTI exhibit higher rates of FAS and marked increase in absolute triacylglycerol levels in leaves, more than 4-fold higher than in wild-type plants. Furthermore, WRINKLED1, a master transcriptional regulator of FAS, positively regulates CTI1 expression by direct binding to its promoter. This study reveals that in addition to light-dependent activation, “envelope docking” of ACCase permits fine-tuning of fatty acid supply during the plant life cycle. In plants, light-dependent activation fatty acid synthesis (FAS) is mediated in part by acetyl-CoA carboxylase (ACCase). Here the authors identify a family of genes encoding carboxyltransferase interactors that attenuate FAS in the light by docking acetyl-CoA carboxylase to the plastid envelope.
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The Protein-Protein Interaction Network Reveals a Novel Role of the Signal Transduction Protein PII in the Control of c-di-GMP Homeostasis in Azospirillum brasilense. mSystems 2020; 5:5/6/e00817-20. [PMID: 33144311 PMCID: PMC7646526 DOI: 10.1128/msystems.00817-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The PII proteins sense and integrate important metabolic signals which reflect the cellular nutrition and energy status. Such extraordinary ability was capitalized by nature in such a way that the various PII proteins regulate different facets of metabolism by controlling the activity of a range of target proteins by protein-protein interactions. Here, we determined the PII protein interaction network in the plant growth-promoting nitrogen-fixing bacterium Azospirillum brasilense. The interactome data along with metabolome analysis suggest that PII functions as a master metabolic regulator hub. We provide evidence that PII proteins act to regulate c-di-GMP levels in vivo and cell motility and adherence behaviors. The PII family comprises a group of widely distributed signal transduction proteins ubiquitous in prokaryotes and in the chloroplasts of plants. PII proteins sense the levels of key metabolites ATP, ADP, and 2-oxoglutarate, which affect the PII protein structure and thereby the ability of PII to interact with a range of target proteins. Here, we performed multiple ligand fishing assays with the PII protein orthologue GlnZ from the plant growth-promoting nitrogen-fixing bacterium Azospirillum brasilense to identify 37 proteins that are likely to be part of the PII protein-protein interaction network. Among the PII targets identified were enzymes related to nitrogen and fatty acid metabolism, signaling, coenzyme synthesis, RNA catabolism, and transcription. Direct binary PII-target complex was confirmed for 15 protein complexes using pulldown assays with recombinant proteins. Untargeted metabolome analysis showed that PII is required for proper homeostasis of important metabolites. Two enzymes involved in c-di-GMP metabolism were among the identified PII targets. A PII-deficient strain showed reduced c-di-GMP levels and altered aerotaxis and flocculation behavior. These data support that PII acts as a major metabolic hub controlling important enzymes and the homeostasis of key metabolites such as c-di-GMP in response to the prevailing nutritional status. IMPORTANCE The PII proteins sense and integrate important metabolic signals which reflect the cellular nutrition and energy status. Such extraordinary ability was capitalized by nature in such a way that the various PII proteins regulate different facets of metabolism by controlling the activity of a range of target proteins by protein-protein interactions. Here, we determined the PII protein interaction network in the plant growth-promoting nitrogen-fixing bacterium Azospirillum brasilense. The interactome data along with metabolome analysis suggest that PII functions as a master metabolic regulator hub. We provide evidence that PII proteins act to regulate c-di-GMP levels in vivo and cell motility and adherence behaviors.
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Forchhammer K, Selim KA. Carbon/nitrogen homeostasis control in cyanobacteria. FEMS Microbiol Rev 2020; 44:33-53. [PMID: 31617886 PMCID: PMC8042125 DOI: 10.1093/femsre/fuz025] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/14/2019] [Indexed: 02/06/2023] Open
Abstract
Carbon/nitrogen (C/N) balance sensing is a key requirement for the maintenance of cellular homeostasis. Therefore, cyanobacteria have evolved a sophisticated signal transduction network targeting the metabolite 2-oxoglutarate (2-OG), the carbon skeleton for nitrogen assimilation. It serves as a status reporter for the cellular C/N balance that is sensed by transcription factors NtcA and NdhR and the versatile PII-signaling protein. The PII protein acts as a multitasking signal-integrating regulator, combining the 2-OG signal with the energy state of the cell through adenyl-nucleotide binding. Depending on these integrated signals, PII orchestrates metabolic activities in response to environmental changes through binding to various targets. In addition to 2-OG, other status reporter metabolites have recently been discovered, mainly indicating the carbon status of the cells. One of them is cAMP, which is sensed by the PII-like protein SbtB. The present review focuses, with a main emphasis on unicellular model strains Synechoccus elongatus and Synechocystis sp. PCC 6803, on the physiological framework of these complex regulatory loops, the tight linkage to metabolism and the molecular mechanisms governing the signaling processes.
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Affiliation(s)
- Karl Forchhammer
- Lehrstuhl für Mikrobiologie, Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
| | - Khaled A Selim
- Lehrstuhl für Mikrobiologie, Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
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Selim KA, Ermilova E, Forchhammer K. From cyanobacteria to Archaeplastida: new evolutionary insights into PII signalling in the plant kingdom. THE NEW PHYTOLOGIST 2020; 227:722-731. [PMID: 32077495 DOI: 10.1111/nph.16492] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 02/13/2020] [Indexed: 05/20/2023]
Abstract
The PII superfamily consists of signal transduction proteins found in all domains of life. Canonical PII proteins sense the cellular energy state through the competitive binding of ATP and ADP, and carbon/nitrogen balance through 2-oxoglutarate binding. The ancestor of Archaeplastida inherited its PII signal transduction protein from an ancestral cyanobacterial endosymbiont. Over the course of evolution, plant PII proteins acquired a glutamine-sensing C-terminal extension, subsequently present in all Chloroplastida PII proteins. The PII proteins of various algal strains (red, green and nonphotosynthetic algae) have been systematically investigated with respect to their sensory and regulatory properties. Comparisons of the PII proteins from different phyla of oxygenic phototrophs (cyanobacteria, red algae, Chlorophyta and higher plants) have yielded insights into their evolutionary conservation vs adaptive properties. The highly conserved role of the controlling enzyme of arginine biosynthesis, N-acetyl-l-glutamate kinase (NAGK), as a main PII-interactor has been demonstrated across oxygenic phototrophs of cyanobacteria and Archaeplastida. In addition, the PII signalling system of red algae has been identified as an evolutionary intermediate between that of Cyanobacteria and Chloroplastida. In this review, we consider recent advances in understanding metabolic signalling by PII proteins of the plant kingdom.
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Affiliation(s)
- Khaled A Selim
- Organismic Interactions Department, Interfaculty Institute of Microbiology and Infection Medicine, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Elena Ermilova
- Biological Faculty, Saint-Petersburg State University, Universitetskaya nab. 7/9, Saint-Petersburg, 199034, Russia
| | - Karl Forchhammer
- Organismic Interactions Department, Interfaculty Institute of Microbiology and Infection Medicine, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
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31
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Allotey P, Tan DT, Kirby T, Tan LH. Community Engagement in Support of Moving Toward Universal Health Coverage. Health Syst Reform 2020; 5:66-77. [PMID: 30924744 DOI: 10.1080/23288604.2018.1541497] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Community engagement describes a complex political process with dynamic negotiation and renegotiation of power and authority between providers and recipients of health care in order to achieve a shared goal of universal health care coverage. Though examples exist of community engagement projects, there is very little guidance on how to implement and embed community engagement as a concerted, integrated, strategic, and sustained component of health systems. Through a series of case studies, this article explores the factors that enable community engagement particularly with a direct impact on health systems.
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Affiliation(s)
- Pascale Allotey
- a UN University International Institute for Global Health UNU-IIGH , Federal Territory of Kuala Lumpur , Malaysia
| | - David T Tan
- a UN University International Institute for Global Health UNU-IIGH , Federal Territory of Kuala Lumpur , Malaysia
| | - Thomas Kirby
- a UN University International Institute for Global Health UNU-IIGH , Federal Territory of Kuala Lumpur , Malaysia
| | - Liza Haslan Tan
- a UN University International Institute for Global Health UNU-IIGH , Federal Territory of Kuala Lumpur , Malaysia
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32
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Rolletschek H, Schwender J, König C, Chapman KD, Romsdahl T, Lorenz C, Braun HP, Denolf P, Van Audenhove K, Munz E, Heinzel N, Ortleb S, Rutten T, McCorkle S, Borysyuk T, Guendel A, Shi H, Vander Auwermeulen M, Bourot S, Borisjuk L. Cellular Plasticity in Response to Suppression of Storage Proteins in the Brassica napus Embryo. THE PLANT CELL 2020; 32:2383-2401. [PMID: 32358071 PMCID: PMC7346569 DOI: 10.1105/tpc.19.00879] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 04/15/2020] [Accepted: 04/30/2020] [Indexed: 05/16/2023]
Abstract
The tradeoff between protein and oil storage in oilseed crops has been tested here in oilseed rape (Brassica napus) by analyzing the effect of suppressing key genes encoding protein storage products (napin and cruciferin). The phenotypic outcomes were assessed using NMR and mass spectrometry imaging, microscopy, transcriptomics, proteomics, metabolomics, lipidomics, immunological assays, and flux balance analysis. Surprisingly, the profile of storage products was only moderately changed in RNA interference transgenics. However, embryonic cells had undergone remarkable architectural rearrangements. The suppression of storage proteins led to the elaboration of membrane stacks enriched with oleosin (sixfold higher protein abundance) and novel endoplasmic reticulum morphology. Protein rebalancing and amino acid metabolism were focal points of the metabolic adjustments to maintain embryonic carbon/nitrogen homeostasis. Flux balance analysis indicated a rather minor additional demand for cofactors (ATP and NADPH). Thus, cellular plasticity in seeds protects against perturbations to its storage capabilities and, hence, contributes materially to homeostasis. This study provides mechanistic insights into the intriguing link between lipid and protein storage, which have implications for biotechnological strategies directed at improving oilseed crops.
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Affiliation(s)
- Hardy Rolletschek
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
| | - Jörg Schwender
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
| | - Christina König
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
| | - Kent D Chapman
- University of North Texas, BioDiscovery Institute, Department of Biological Sciences, Denton, Texas 76203
| | - Trevor Romsdahl
- University of North Texas, BioDiscovery Institute, Department of Biological Sciences, Denton, Texas 76203
| | - Christin Lorenz
- Institut für Pflanzengenetik, Universität Hannover, 30419 Hannover, Germany
| | - Hans-Peter Braun
- Institut für Pflanzengenetik, Universität Hannover, 30419 Hannover, Germany
| | - Peter Denolf
- BASF Innovation Center Ghent, 9052-Zwijnaarde, Belgium
| | | | - Eberhard Munz
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
| | - Nicolas Heinzel
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
| | - Stefan Ortleb
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
| | - Twan Rutten
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
| | - Sean McCorkle
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
| | | | - André Guendel
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
| | - Hai Shi
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
| | | | | | - Ljudmilla Borisjuk
- Leibniz Institute of Plant Genetics and Crop Plant Research OT Gatersleben, D-06466 Seeland, Germany
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To A, Joubès J, Thueux J, Kazaz S, Lepiniec L, Baud S. AtMYB92 enhances fatty acid synthesis and suberin deposition in leaves of Nicotiana benthamiana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:660-676. [PMID: 32246506 DOI: 10.1111/tpj.14759] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 02/02/2020] [Accepted: 03/18/2020] [Indexed: 05/11/2023]
Abstract
Acyl lipids are important constituents of the plant cell. Depending on the cell type, requirements in acyl lipids vary greatly, implying a tight regulation of fatty acid and lipid metabolism. The discovery of the WRINKLED1 (WRI1) transcription factors, members of the AP2-EREBP (APETALA2-ethylene-responsive element binding protein) family, has emphasized the importance of transcriptional regulation for adapting the rate of acyl chain production to cell requirements. Here, we describe the identification of another activator of the fatty acid biosynthetic pathway, the Arabidopsis MYB92 transcription factor. This MYB and all the members of the subgroups S10 and S24 of MYB transcription factors can directly activate the promoter of BCCP2 that encodes a component of the fatty acid biosynthetic pathway. Two adjacent MYB cis-regulatory elements are essential for the binding and activation of the BCCP2 promoter by MYB92. Overexpression of MYB92 or WRI1 in Nicotiana benthamiana induces the expression of fatty acid biosynthetic genes but results in the accumulation of different types of acyl lipids. In the presence of WRI1, triacylglycerol biosynthetic enzymes coded by constitutively expressed genes efficiently channel the excess fatty acids toward reserve lipid accumulation. By contrast, MYB92 activates both fatty acid and suberin biosynthetic genes; hence, the remarkable increase in suberin monomers measured in leaves expressing MYB92. These results provide additional insight into the molecular mechanisms that control the biosynthesis of an important cell wall-associated acylglycerol polymer playing critical roles in plants.
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Affiliation(s)
- Alexandra To
- Institut Jean-Pierre Bourgin, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Jérôme Joubès
- Laboratoire de Biogenèse Membranaire, UMR 5200, Université de Bordeaux, 33882, Villenave d'Ornon, France
- Laboratoire de Biogenèse Membranaire, UMR 5200, CNRS, 33882, Villenave d'Ornon, France
| | - Jean Thueux
- Institut Jean-Pierre Bourgin, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Sami Kazaz
- Institut Jean-Pierre Bourgin, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
- Université Paris-Sud, Université Paris-Saclay, 91400, Orsay, France
| | - Loïc Lepiniec
- Institut Jean-Pierre Bourgin, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
| | - Sébastien Baud
- Institut Jean-Pierre Bourgin, INRAE, CNRS, AgroParisTech, Université Paris-Saclay, 78000, Versailles, France
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Shivaiah KK, Ding G, Upton B, Nikolau BJ. Non-Catalytic Subunits Facilitate Quaternary Organization of Plastidic Acetyl-CoA Carboxylase. PLANT PHYSIOLOGY 2020; 182:756-775. [PMID: 31792149 PMCID: PMC6997691 DOI: 10.1104/pp.19.01246] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 11/19/2019] [Indexed: 05/18/2023]
Abstract
Arabidopsis (Arabidopsis thaliana), like most dicotyledonous plants, expresses a multicomponent, heteromeric acetyl-CoA carboxylase (htACCase), which catalyzes the generation of the malonyl-CoA precursor of de novo fatty acid biosynthesis. This enzyme consists of four catalytic subunits: biotin carboxylase (BC), carboxyltransferase (CT)-α, CT-β, and biotin carboxyl carrier protein (BCCP1 or BCCP2). By coexpressing combinations of components in a bacterial expression system, we demonstrate noncatalytic BADCs facilitate the assembly and activation of BCCP-BADC-BC subcomplexes catalyzing the bicarbonate-dependent hydrolysis of ATP, which is the first half-reaction catalyzed by the htACCase enzyme. Although BADC proteins do not directly impact formation of the CT-αβ subcomplex, the BADC-facilitated BCCP-BADC-BC subcomplex can more readily interact with the CT-αβ subcomplex to facilitate the generation of malonyl-CoA. The Arabidopsis genome encodes three BADC isoforms (BADC1, BADC2, and BADC3), and BADC2 and BADC3 (rather than BADC1), in combination with BCCP1, best support this quaternary-structural organization and catalytic activation of the htACCase enzyme. Physiological genetic studies validate these attributes as Arabidopsis double mutants singularly expressing BADC2, BADC3, or BADC1 present increasingly greater deleterious impacts on morphological and biochemical phenotypes. Specifically, plants expressing only BADC2 develop normally, plants only expressing BADC3 suffer a stunted root-growth phenotype, and plants expressing only BADC1 are embryo-lethal. The latter phenotype may also be associated with the distinct suborganelle localization of BADC1 in plastids as compared to the localization of the other two BADC homologs. These finding can inspire novel strategies to improve the biological sources of fats and oils for dietary and industrial applications.
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Affiliation(s)
- Kiran-Kumar Shivaiah
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
| | - Geng Ding
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
| | - Bryon Upton
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
| | - Basil J Nikolau
- Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011
- Center for Biorenewable Chemicals, Iowa State University, Ames, Iowa 50011
- Center for Metabolic Biology, Iowa State University, Ames, Iowa 50011
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35
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He M, Qin CX, Wang X, Ding NZ. Plant Unsaturated Fatty Acids: Biosynthesis and Regulation. FRONTIERS IN PLANT SCIENCE 2020; 11:390. [PMID: 32425958 PMCID: PMC7212373 DOI: 10.3389/fpls.2020.00390] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/18/2020] [Indexed: 05/11/2023]
Abstract
In most plants, major unsaturated fatty acids (UFAs) are three C18 species, namely, oleic (18:1), linoleic (18:2), and α-linolenic (18:3) acids. These simple compounds play multiple crucial roles in planta and are also important economic traits of oil crops. The enzymatic steps of C18 UFA biosynthesis have been well established. However, the associated FA/lipid trafficking between the plastid and the endoplasmic reticulum remains largely unclear, as does the regulation of the expression and activities of the involved enzymes. In this review, we will revisit the biosynthesis of C18 UFAs with an emphasis on the trafficking, and present an overview of the key enzymes and their regulation. Of particular interest is the emerging regulatory network composed of transcriptional factors and upstream signaling pathways. The review thereby provides the promise of using physical, biochemical and/or genetic means to manipulate FA composition and increase oil yield in crop improvement.
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Selim KA, Haffner M, Watzer B, Forchhammer K. Tuning the in vitro sensing and signaling properties of cyanobacterial PII protein by mutation of key residues. Sci Rep 2019; 9:18985. [PMID: 31831819 PMCID: PMC6908673 DOI: 10.1038/s41598-019-55495-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/13/2019] [Indexed: 11/09/2022] Open
Abstract
PII proteins comprise an ancient superfamily of signal transduction proteins, widely distributed among all domains of life. In general, PII proteins measure and integrate the current carbon/nitrogen/energy status of the cell through interdependent binding of ATP, ADP and 2-oxogluterate. In response to effector molecule binding, PII proteins interact with various PII-receptors to tune central carbon- and nitrogen metabolism. In cyanobacteria, PII regulates, among others, the key enzyme for nitrogen-storage, N-acetyl-glutamate kinase (NAGK), and the co-activator of the global nitrogen-trascription factor NtcA, the PII-interacting protein-X (PipX). One of the remarkable PII variants from Synechococcus elongatus PCC 7942 that yielded mechanistic insights in PII-NAGK interaction, is the NAGK-superactivating variant I86N. Here we studied its interaction with PipX. Another critical residue is Lys58, forming a salt-bridge with 2-oxoglutarate in a PII-ATP-2-oxoglutarate complex. Here, we show that Lys58 of PII protein is a key residue for mediating PII interactions. The K58N mutation not only causes the loss of 2-oxogluterate binding but also strongly impairs binding of ADP, NAGK and PipX. Remarkably, the exchange of the nearby Leu56 to Lys in the K58N variant partially compensates for the loss of K58. This study demonstrates the potential of creating custom tailored PII variants to modulate metabolism.
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Affiliation(s)
- Khaled A Selim
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Organismic Interactions, Eberhard Karls University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany.
| | - Michael Haffner
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Organismic Interactions, Eberhard Karls University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Björn Watzer
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Organismic Interactions, Eberhard Karls University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Karl Forchhammer
- Interfaculty Institute of Microbiology and Infection Medicine, Department of Organismic Interactions, Eberhard Karls University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
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Lapina TV, Kochemasova LY, Forchhammer K, Ermilova EV. Effects of arginine on Polytomella parva growth, PII protein levels and lipid body formation. PLANTA 2019; 250:1379-1385. [PMID: 31359139 DOI: 10.1007/s00425-019-03249-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/25/2019] [Indexed: 06/10/2023]
Abstract
L-Arginine supports growth and resulted in increased PII signaling protein levels and lipid droplet accumulation in the colorless green alga Polytomella parva. Polytomella parva, a model system for nonphotosynthetic green algae, utilizes ammonium and several carbon sources, including ethanol and acetate. We previously reported that P. parva accumulates high amounts of arginine with the key enzyme of the ornithine/arginine biosynthesis pathway, N-acetyl-L-glutamate kinase, exhibiting high activity. Here we demonstrate that L-arginine can be used by this alga as a nitrogen source. Externally supplied arginine directly influenced the levels of PII signaling protein and formation of triacylglycerol (TAG)-filled lipid bodies (LBs). Our results suggest that the nitrogen source, but not nitrogen starvation, may be critical for the accumulation of LBs in a PII-independent manner in P. parva.
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Affiliation(s)
- Tatiana V Lapina
- Biological Faculty, Saint-Petersburg State University, Universitetskaya nab. 7/9, Saint-Petersburg, Russia, 199034
| | - Lidiya Yu Kochemasova
- Biological Faculty, Saint-Petersburg State University, Universitetskaya nab. 7/9, Saint-Petersburg, Russia, 199034
| | - Karl Forchhammer
- Organismic Interactions Department, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - Elena V Ermilova
- Biological Faculty, Saint-Petersburg State University, Universitetskaya nab. 7/9, Saint-Petersburg, Russia, 199034.
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38
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Condori-Apfata JA, Batista-Silva W, Medeiros DB, Vargas JR, Valente LML, Heyneke E, Pérez-Diaz JL, Fernie AR, Araújo WL, Nunes-Nesi A. The Arabidopsis E 1 subunit of the 2-oxoglutarate dehydrogenase complex modulates plant growth and seed production. PLANT MOLECULAR BIOLOGY 2019; 101:183-202. [PMID: 31286324 DOI: 10.1007/s11103-019-00900-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 06/29/2019] [Indexed: 05/25/2023]
Abstract
Isoforms of 2-OGDH E1 subunit are not functionally redundant in plant growth and development of A. thaliana. The tricarboxylic acid cycle enzyme 2-oxoglutarate dehydrogenase (2-OGDH) converts 2-oxoglutarate (2-OG) to succinyl-CoA concomitant with the reduction of NAD+. 2-OGDH has an essential role in plant metabolism, being both a limiting step during mitochondrial respiration as well as a key player in carbon-nitrogen interactions. In Arabidopsis thaliana two genes encode for E1 subunit of 2-OGDH but the physiological roles of each isoform remain unknown. Thus, in the present study we isolated Arabidopsis T-DNA insertion knockout mutant lines for each of the genes encoding the E1 subunit of 2-OGDH enzyme. All mutant plants exhibited substantial reduction in both respiration and CO2 assimilation rates. Furthermore, mutant lines exhibited reduced levels of chlorophylls and nitrate, increased levels of sucrose, malate and fumarate and minor changes in total protein and starch levels in leaves. Despite the similar metabolic phenotypes for the two E1 isoforms the reduction in the expression of each gene culminated in different responses in terms of plant growth and seed production indicating distinct roles for each isoform. Collectively, our results demonstrated the importance of the E1 subunit of 2-OGDH in both autotrophic and heterotrophic tissues and suggest that the two E1 isoforms are not functionally redundant in terms of plant growth in A. thaliana.
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Affiliation(s)
- Jorge A Condori-Apfata
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Willian Batista-Silva
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - David Barbosa Medeiros
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Jonas Rafael Vargas
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Luiz Mário Lopes Valente
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Elmien Heyneke
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam Golm, Germany
| | - Jorge Luis Pérez-Diaz
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam Golm, Germany
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil.
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Calabrò E, Magazù S. New Perspectives in the Treatment of Tumor Cells by Electromagnetic Radiation at Resonance Frequencies in Cellular Membrane Channels. ACTA ACUST UNITED AC 2019. [DOI: 10.2174/187407070190130105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background:
The use of electromagnetic fields has been considered as adjuvant therapy for the treatment of cancer given that some clinical trials have shown that the irradiation of cancer cells with electromagnetic fields can slow down the disease progression.
Aims:
We hypothesize that this effect could be amplified by irradiating tumor cells with electromagnetic fields having frequencies close to the natural resonant frequencies of membrane channels in tumor cells, in order to obtain a significant change of the ion flux across tumor cell membrane channels, inducing the largest harmful alteration in their cellular function.
Methods:
Neuronal-like cells were used as a cell model and exposed for 6 h to electromagnetic fields at different frequencies (0, 50 Hz, 900 MHz) at the same intensity of 2 mT. The exposure system was represented by two Helmholtz coils driven by a power amplifier in current mode and an arbitrary function generator. FTIR spectroscopy was used to evaluate the results of the exposure.
Results:
The results of this study showed that the Amide I vibration band increased in intensity with the increase of the frequency, leading us to assume that the displacement of the cell channels α-helices depends on the frequency of the applied electromagnetic fields.
Conclusion:
This preliminary result leads us to plan future research aimed at searching for the natural frequencies of membrane channels in tumor cells using resonant electromagnetic fields in order to damage the cellular functions of tumor cells. Clinical trials are needed to confirm such a hypothesis derived from this physical study.
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Cantos R, Labella JI, Espinosa J, Contreras A. The nitrogen regulator PipX acts in cis to prevent operon polarity. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:495-507. [PMID: 30126050 DOI: 10.1111/1758-2229.12688] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 07/10/2018] [Accepted: 08/10/2018] [Indexed: 06/08/2023]
Abstract
Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to important environmental challenges, like those imposed by the succession of days and nights. Not surprisingly, certain regulatory proteins are found exclusively in this phylum. One of these unique factors, PipX, provides a mechanistic link between signals of carbon/nitrogen and of energy, transduced by the signalling protein PII, and the control of gene expression by the global nitrogen regulator NtcA. Here we report a new regulatory function of PipX: enhancement in cis of pipY expression, a gene encoding a universally conserved protein involved in amino/keto acid and Pyridoxal phosphate homeostasis. In Synechococcus elongatus and many other cyanobacteria these genes are expressed as a bicistronic pipXY operon. Despite being cis-acting, polarity suppression by PipX is nevertheless reminiscent of the function of NusG paralogues typified by RfaH, which are non-essential operon-specific bacterial factors acting in trans to upregulate horizontally-acquired genes. Furthermore, PipX and members of the NusG superfamily share a TLD/KOW structural domain, suggesting regulatory interactions of PipX with the translation machinery. Our results also suggest that the cis-acting function of PipX is a sophisticated regulatory strategy for maintaining appropriate PipX-PipY stoichiometry.
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Affiliation(s)
- Raquel Cantos
- Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - Jose I Labella
- Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - Javier Espinosa
- Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - Asunción Contreras
- Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
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41
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Guzmán-Castañeda SJ, Ortega-Vega EL, de la Cuesta-Zuluaga J, Velásquez-Mejía EP, Rojas W, Bedoya G, Escobar JS. Gut microbiota composition explains more variance in the host cardiometabolic risk than genetic ancestry. Gut Microbes 2019; 11:191-204. [PMID: 31311405 PMCID: PMC7053924 DOI: 10.1080/19490976.2019.1634416] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 05/10/2019] [Accepted: 06/16/2019] [Indexed: 02/03/2023] Open
Abstract
Cardiometabolic affections greatly contribute to the global burden of disease. The susceptibility to obesity, cardiovascular disease, and type-2 diabetes, conditions that add to the cardiometabolic syndrome (CMS), was associated with the ancestral genetic composition and gut microbiota. Studies explicitly testing associations between genetic ancestry and gut microbes are growing. We here examined whether the host genetic ancestry was associated with gut microbiota composition, and distinguished the effects of genetic ancestry and non-genetic factors on human cardiometabolic health. We performed a cross-sectional study with 441 community-dwelling Colombian mestizos from five cities spanning the Andes, Pacific, and Caribbean coasts. We characterized the host genetic ancestry by genotyping 40 ancestry informative markers; characterized gut microbiota through 16S rRNA gene sequencing; assessed diet intake, physical activity, cigarette, and medicament consumption; and measured cardiometabolic outcomes that allowed calculating a CMS risk scale. On average, each individual of our cohort was 67 ± 6% European, 21 ± 5% Native American and 12 ± 5% African. Multivariable-adjusted generalized linear models showed that individuals with higher Native American and African ancestries had increased fasting insulin, body mass index and CMS risk, as assessed by the CMS risk scale. Furthermore, we identified 21 OTUs associated to the host genetic ancestry and 20 to cardiometabolic health. While we highlight novel associations between genetic ancestry and gut microbiota, we found that the effect of intestinal microbes was more likely to explain the variance in CMS risk scale than the contributions of European, Native American and African genetic backgrounds.
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Affiliation(s)
- Sandra J. Guzmán-Castañeda
- Grupo de Investigación en Genética Molecular (GENMOL), Sede de Investigación Universitaria, Universidad de Antioquia, Medellin, Colombia
| | - Esteban L. Ortega-Vega
- Grupo de Investigación en Genética Molecular (GENMOL), Sede de Investigación Universitaria, Universidad de Antioquia, Medellin, Colombia
| | - Jacobo de la Cuesta-Zuluaga
- Vidarium–Nutrition, Health and Wellness Research Center, Grupo Empresarial Nutresa, Medellin, Colombia
- Department of Microbiome Science, Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Eliana P. Velásquez-Mejía
- Vidarium–Nutrition, Health and Wellness Research Center, Grupo Empresarial Nutresa, Medellin, Colombia
| | - Winston Rojas
- Grupo de Investigación en Genética Molecular (GENMOL), Sede de Investigación Universitaria, Universidad de Antioquia, Medellin, Colombia
| | - Gabriel Bedoya
- Grupo de Investigación en Genética Molecular (GENMOL), Sede de Investigación Universitaria, Universidad de Antioquia, Medellin, Colombia
| | - Juan S. Escobar
- Vidarium–Nutrition, Health and Wellness Research Center, Grupo Empresarial Nutresa, Medellin, Colombia
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Milich DR. Is the function of the HBeAg really unknown? Hum Vaccin Immunother 2019; 15:2187-2191. [PMID: 31063442 PMCID: PMC6773382 DOI: 10.1080/21645515.2019.1607132] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 04/01/2019] [Accepted: 04/08/2019] [Indexed: 12/21/2022] Open
Abstract
The immune response to the hepatitis B virus (HBV) vaccine in newborns of hepatitis B e antigen (HBeAg)-positive or HBeAg-negative mothers is the subject of Huang et al. The authors report no correlation between the HBeAg status of the mothers/cord blood and the newborns immune response to the vaccine, but, unfortunately, draw unfounded conclusions regarding the tolerogenic potential of in utero exposure to HBeAg. In this reply, I address the possible influence of in utero exposure to the HBeAg, and briefly review other characteristics of the HBeAg, that may promote HBV chronicity. I argue that the function of HBeAg should no longer be considered "unknown" and that immunotolerance/immunomodulation represent the dominant functions of the HBeAg in viral-host interactions.
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Affiliation(s)
- David R. Milich
- Department of Immunology, Vaccine Research Institute of San Diego, San Diego, CA, USA
- VLP Biotech, Inc., La Jolla, CA, USA
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43
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Choi H, Phillips C, Oh JY, Potts L, Reger RL, Prockop DJ, Fulcher S. Absence of Therapeutic Benefit of the Anti-Inflammatory Protein TSG-6 for Corneal Alkali Injury in a Rat Model. Curr Eye Res 2019; 44:873-881. [PMID: 30935217 DOI: 10.1080/02713683.2019.1597893] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Purpose: To investigate the therapeutic efficacy of tumor necrosis factor (TNF)-α stimulated gene/protein 6 (TSG-6) in a rat model of corneal alkali injury. Methods: Corneal alkali injury was produced by placing an NaOH-soaked filter paper disk on the central cornea of the right eye of an anesthetized male Lewis (LEW/Crl) rat. Recombinant human TSG-6, or an equal volume of phosphate-buffered saline (PBS), was administered intravenously (IV), by anterior chamber (AC) injection, or as a topical drop. The affected eyes were photographed daily using a dissecting microscope and documented for clinical time course analysis of corneal opacification. Corneal tissue was excised at pre-determined therapeutic endpoints, with subsequent qRT-PCR or histological analyses. Results: The continuous monitoring of corneal alkali injury progression revealed TSG-6 treatments do not show sufficient effectiveness in vivo regardless of IV injection, AC injection, or topical application. Corneal opacification and neovascularization were not diminished, and gene expression was not impacted by these treatments. However, both IV and AC administration of TSG-6 significantly suppressed pro-inflammatory cytokines compared to PBS-treated eyes. Conclusion: We conclude that the therapeutic potential of TSG-6 is insufficient in a rat corneal alkali injury model.
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Affiliation(s)
- Hosoon Choi
- a Department of Basic Research, Central Texas Veterans Research Foundation , Temple , Texas , USA
| | - Casie Phillips
- a Department of Basic Research, Central Texas Veterans Research Foundation , Temple , Texas , USA
| | - Joo Youn Oh
- b Department of Ophthalmology, Seoul National University Hospital , Seoul , Republic of Korea
| | - Luke Potts
- c Department of Ophthalmology and Surgery, Scott and White Eye Institute , Temple , Texas , USA
| | - Roxanne L Reger
- d Institute for Regenerative Medicine, College of Medicine, Texas A&M University , College Station , Texas , USA
| | - Darwin J Prockop
- d Institute for Regenerative Medicine, College of Medicine, Texas A&M University , College Station , Texas , USA
| | - Samuel Fulcher
- e Department of Surgery, Central Texas Veterans Health Care System , Temple , Texas , United States of America
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44
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Zhou T, Xue Y, Zhang Z, Dong Y, Gao R, Li Y. Improvement of the Characteristics of Steamed Bread by Supplementation of Recombinant alpha-L-arabinofuranosidase Containing xylan-binding domain. FOOD BIOTECHNOL 2019. [DOI: 10.1080/08905436.2018.1553048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Tao Zhou
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Yemin Xue
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Zonghui Zhang
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Yuanyuan Dong
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Rui Gao
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Yaxian Li
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
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45
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Li-Beisson Y, Thelen JJ, Fedosejevs E, Harwood JL. The lipid biochemistry of eukaryotic algae. Prog Lipid Res 2019; 74:31-68. [PMID: 30703388 DOI: 10.1016/j.plipres.2019.01.003] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 01/22/2019] [Accepted: 01/23/2019] [Indexed: 02/06/2023]
Abstract
Algal lipid metabolism fascinates both scientists and entrepreneurs due to the large diversity of fatty acyl structures that algae produce. Algae have therefore long been studied as sources of genes for novel fatty acids; and, due to their superior biomass productivity, algae are also considered a potential feedstock for biofuels. However, a major issue in a commercially viable "algal oil-to-biofuel" industry is the high production cost, because most algal species only produce large amounts of oils after being exposed to stress conditions. Recent studies have therefore focused on the identification of factors involved in TAG metabolism, on the subcellular organization of lipid pathways, and on interactions between organelles. This has been accompanied by the development of genetic/genomic and synthetic biological tools not only for the reference green alga Chlamydomonas reinhardtii but also for Nannochloropsis spp. and Phaeodactylum tricornutum. Advances in our understanding of enzymes and regulatory proteins of acyl lipid biosynthesis and turnover are described herein with a focus on carbon and energetic aspects. We also summarize how changes in environmental factors can impact lipid metabolism and describe present and potential industrial uses of algal lipids.
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Affiliation(s)
- Yonghua Li-Beisson
- Aix-Marseille Univ, CEA, CNRS, BIAM, UMR7265, CEA Cadarache, Saint-Paul-lez Durance F-13108, France.
| | - Jay J Thelen
- Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, United States.
| | - Eric Fedosejevs
- Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, United States.
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.
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Machiavelli A, Duarte RTD, Pires MMDS, Zárate-Bladés CR, Pinto AR. The impact of in utero HIV exposure on gut microbiota, inflammation, and microbial translocation. Gut Microbes 2019; 10:599-614. [PMID: 30657007 PMCID: PMC6748604 DOI: 10.1080/19490976.2018.1560768] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
HIV-exposed but uninfected (HEU) children represent a growing population and show a significantly higher number of infectious diseases, several immune alterations, compromised growth, and increased mortality rates when compared to HIV-unexposed children. Considering the impact that the gut microbiota has on general host homeostasis and immune system development and modulation, we hypothesized that HEU children present altered gut microbiota that is linked to the increased morbidity and the immune system disorders faced by them. Our experiments revealed no differences in beta and alpha diversity of the gut microbiota between HEU and unexposed children or between HIV-infected and uninfected mothers. However, there were differences in the abundance of several taxa from the gut microbiota between HEU and unexposed children and between HIV-infected and uninfected mothers. Functional prediction based on 16S rRNA sequences also indicated differences between HEU and unexposed children and between infected and uninfected mothers. In addition, we detected no differences between HEU and unexposed children in relation to weight, weight-for-age z scores, albumin serum levels, or microbial translocation and inflammation markers. In summary, HIV-infected mothers and their HIV-exposed children present alterations in the abundance of several taxa in the gut microbiome and the predicted functional metagenome when compared to uninfected mothers and unexposed children. Knowledge about the gut microbiome of HEU children in different settings is essential in order to determine better treatments for this susceptible population.
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Affiliation(s)
- Aline Machiavelli
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Rubens T. Delgado Duarte
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Maria M. de Souza Pires
- Departamento de Pediatria, Universidade Federal de Santa Catarina, Florianópolis, Brazil,Hospital Infantil Joana de Gusmão, Florianópolis, Brazil
| | - Carlos R. Zárate-Bladés
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Aguinaldo R. Pinto
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil,CONTACT Aguinaldo R. Pinto Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
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47
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Fatty acid biosynthesis is enhanced in Escherichia coli strains with deletion in genes encoding the PII signaling proteins. Arch Microbiol 2018; 201:209-214. [PMID: 30506165 DOI: 10.1007/s00203-018-1603-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/08/2018] [Accepted: 11/24/2018] [Indexed: 10/27/2022]
Abstract
The committed and rate-limiting step in fatty acid biosynthesis is catalyzed by acetyl-CoA carboxylase (ACC). In previous studies we showed that ACC activity is inhibited through interactions with the PII signaling proteins in vitro. Here we provide in vivo support for that model; we noted that PII proteins are able to reduce malonyl-CoA levels in vivo in Escherichia coli. Furthermore, we show that fatty acid biosynthesis is strongly enhanced in E. coli strains carrying deletions in PII coding genes. Given that PII proteins act as conserved negative regulators of ACC in Bacteria, our findings may be explored to engineer other prokaryotes to improve fatty acid yields, thereby turning microbial biofuel production economically competitive in the future.
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48
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Szczepaniak A, Książkiewicz M, Podkowiński J, Czyż KB, Figlerowicz M, Naganowska B. Legume Cytosolic and Plastid Acetyl-Coenzyme-A Carboxylase Genes Differ by Evolutionary Patterns and Selection Pressure Schemes Acting before and after Whole-Genome Duplications. Genes (Basel) 2018; 9:genes9110563. [PMID: 30469317 PMCID: PMC6265850 DOI: 10.3390/genes9110563] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 11/09/2018] [Accepted: 11/15/2018] [Indexed: 01/01/2023] Open
Abstract
Acetyl-coenzyme A carboxylase (ACCase, E.C.6.4.1.2) catalyzes acetyl-coenzyme A carboxylation to malonyl coenzyme A. Plants possess two distinct ACCases differing by cellular compartment and function. Plastid ACCase contributes to de novo fatty acid synthesis, whereas cytosolic enzyme to the synthesis of very long chain fatty acids, phytoalexins, flavonoids, and anthocyanins. The narrow leafed lupin (Lupinus angustifolius L.) represents legumes, a plant family which evolved by whole-genome duplications (WGDs). The study aimed on the contribution of these WGDs to the multiplication of ACCase genes and their further evolutionary patterns. The molecular approach involved bacterial artificial chromosome (BAC) library screening, fluorescent in situ hybridization, linkage mapping, and BAC sequencing. In silico analysis encompassed sequence annotation, comparative mapping, selection pressure calculation, phylogenetic inference, and gene expression profiling. Among sequenced legumes, the highest number of ACCase genes was identified in lupin and soybean. The most abundant plastid ACCase subunit genes were accB. ACCase genes in legumes evolved by WGDs, evidenced by shared synteny and Bayesian phylogenetic inference. Transcriptional activity of almost all copies was confirmed. Gene duplicates were conserved by strong purifying selection, however, positive selection occurred in Arachis (accB2) and Lupinus (accC) lineages, putatively predating the WGD event(s). Early duplicated accA and accB genes underwent transcriptional sub-functionalization.
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Affiliation(s)
- Anna Szczepaniak
- Department of Genomics, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Poznań, Poland.
| | - Michał Książkiewicz
- Department of Genomics, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Poznań, Poland.
| | - Jan Podkowiński
- Department of Genomics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznań, Poland.
| | - Katarzyna B Czyż
- Department of Biometry and Bioinformatics, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Poznań, Poland.
| | - Marek Figlerowicz
- Department of Genomics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznań, Poland.
| | - Barbara Naganowska
- Department of Genomics, Institute of Plant Genetics, Polish Academy of Sciences, 60-479 Poznań, Poland.
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Forcada-Nadal A, Llácer JL, Contreras A, Marco-Marín C, Rubio V. The P II-NAGK-PipX-NtcA Regulatory Axis of Cyanobacteria: A Tale of Changing Partners, Allosteric Effectors and Non-covalent Interactions. Front Mol Biosci 2018; 5:91. [PMID: 30483512 PMCID: PMC6243067 DOI: 10.3389/fmolb.2018.00091] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 10/18/2018] [Indexed: 11/13/2022] Open
Abstract
PII, a homotrimeric very ancient and highly widespread (bacteria, archaea, plants) key sensor-transducer protein, conveys signals of abundance or poorness of carbon, energy and usable nitrogen, converting these signals into changes in the activities of channels, enzymes, or of gene expression. PII sensing is mediated by the PII allosteric effectors ATP, ADP (and, in some organisms, AMP), 2-oxoglutarate (2OG; it reflects carbon abundance and nitrogen scarcity) and, in many plants, L-glutamine. Cyanobacteria have been crucial for clarification of the structural bases of PII function and regulation. They are the subject of this review because the information gathered on them provides an overall structure-based view of a PII regulatory network. Studies on these organisms yielded a first structure of a PII complex with an enzyme, (N-acetyl-Lglutamate kinase, NAGK), deciphering how PII can cause enzyme activation, and how it promotes nitrogen stockpiling as arginine in cyanobacteria and plants. They have also revealed the first clear-cut mechanism by which PII can control gene expression. A small adaptor protein, PipX, is sequestered by PII when nitrogen is abundant and is released when is scarce, swapping partner by binding to the 2OG-activated transcriptional regulator NtcA, co-activating it. The structures of PII-NAGK, PII-PipX, PipX alone, of NtcA in inactive and 2OG-activated forms and as NtcA-2OG-PipX complex, explain structurally PII regulatory functions and reveal the changing shapes and interactions of the T-loops of PII depending on the partner and on the allosteric effectors bound to PII. Cyanobacterial studies have also revealed that in the PII-PipX complex PipX binds an additional transcriptional factor, PlmA, thus possibly expanding PipX roles beyond NtcA-dependency. Further exploration of these roles has revealed a functional interaction of PipX with PipY, a pyridoxal-phosphate (PLP) protein involved in PLP homeostasis whose mutations in the human ortholog cause epilepsy. Knowledge of cellular levels of the different components of this PII-PipX regulatory network and of KD values for some of the complexes provides the basic background for gross modeling of the system at high and low nitrogen abundance. The cyanobacterial network can guide searches for analogous components in other organisms, particularly of PipX functional analogs.
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Affiliation(s)
- Alicia Forcada-Nadal
- Instituto de Biomedicina de Valencia del Consejo Superior de Investigaciones Científicas, Valencia, Spain.,Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - José Luis Llácer
- Instituto de Biomedicina de Valencia del Consejo Superior de Investigaciones Científicas, Valencia, Spain.,Group 739, Centro de Investigación Biomédica en Red de Enfermedades Raras - Instituto de Salud Carlos III, Valencia, Spain
| | - Asunción Contreras
- Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - Clara Marco-Marín
- Instituto de Biomedicina de Valencia del Consejo Superior de Investigaciones Científicas, Valencia, Spain.,Group 739, Centro de Investigación Biomédica en Red de Enfermedades Raras - Instituto de Salud Carlos III, Valencia, Spain
| | - Vicente Rubio
- Instituto de Biomedicina de Valencia del Consejo Superior de Investigaciones Científicas, Valencia, Spain.,Group 739, Centro de Investigación Biomédica en Red de Enfermedades Raras - Instituto de Salud Carlos III, Valencia, Spain
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50
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Caldo KMP, Shen W, Xu Y, Hanley-Bowdoin L, Chen G, Weselake RJ, Lemieux MJ. Diacylglycerol acyltransferase 1 is activated by phosphatidate and inhibited by SnRK1-catalyzed phosphorylation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:287-299. [PMID: 30003607 DOI: 10.1111/tpj.14029] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/23/2018] [Accepted: 06/26/2018] [Indexed: 05/06/2023]
Abstract
Diacylglycerol acyltransferase 1 (DGAT1) catalyzes the final and committed step in the Kennedy pathway for triacylglycerol (TAG) biosynthesis and, as such, elucidating its mode of regulation is critical to understand the fundamental aspects of carbon metabolism in oleaginous crops. In this study, purified Brassica napus diacylglycerol acyltransferase 1 (BnaDGAT1) in n-dodecyl-β-d-maltopyranoside micelles was lipidated to form mixed micelles and subjected to detailed biochemical analysis. The degree of mixed micelle fluidity appeared to influence acyltransferase activity. BnaDGAT1 exhibited a sigmoidal response and eventual substrate inhibition with respect to increasing concentrations of oleoyl-CoA. Phosphatidate (PA) was identified as a feed-forward activator of BnaDGAT1, enabling the final enzyme in the Kennedy pathway to adjust to the incoming flow of carbon leading to TAG. In the presence of PA, the oleoyl-CoA saturation plot became more hyperbolic and desensitized to substrate inhibition indicating that PA facilitates the transition of the enzyme into the more active state. PA may also relieve possible autoinhibition of BnaDGAT1 brought about by the N-terminal regulatory domain, which was shown to interact with PA. Indeed, PA is a key effector modulating lipid homeostasis, in addition to its well recognized role in lipid signaling. BnaDGAT1 was also shown to be a substrate of the sucrose non-fermenting-1-related kinase 1 (SnRK1), which catalyzed phosphorylation of the enzyme and converted it to a less active form. Thus, this known regulator of carbon metabolism directly influences TAG biosynthesis.
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Affiliation(s)
- Kristian Mark P Caldo
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2H7, Canada
| | - Wei Shen
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Yang Xu
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Guanqun Chen
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada
| | - Randall J Weselake
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, T6G 2P5, Canada
| | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2H7, Canada
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