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Mueller-Schuessele SJ, Leterme S, Michaud M. Plastid Transient and Stable Interactions with Other Cell Compartments. Methods Mol Biol 2024; 2776:107-134. [PMID: 38502500 DOI: 10.1007/978-1-0716-3726-5_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Plastids are organelles delineated by two envelopes playing important roles in different cellular processes such as energy production or lipid biosynthesis. To regulate their biogenesis and their function, plastids have to communicate with other cellular compartments. This communication can be mediated by metabolites, signaling molecules, and by the establishment of direct contacts between the plastid envelope and other organelles such as the endoplasmic reticulum, mitochondria, peroxisomes, plasma membrane, and the nucleus. These interactions are highly dynamic and respond to different biotic and abiotic stresses. However, the mechanisms involved in the formation of plastid-organelle contact sites and their functions are still far from being understood. In this chapter, we summarize our current knowledge about plastid contact sites and their role in the regulation of plastid biogenesis and function.
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Affiliation(s)
| | - Sébastien Leterme
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, CEA, INRAE, Univ. Grenoble Alpes, IRIG, CEA Grenoble, Grenoble, France
| | - Morgane Michaud
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, CEA, INRAE, Univ. Grenoble Alpes, IRIG, CEA Grenoble, Grenoble, France.
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2
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Saroussi S, Redekop P, Karns DAJ, Thomas DC, Wittkopp TM, Posewitz MC, Grossman AR. Restricting electron flow at cytochrome b6f when downstream electron acceptors are severely limited. PLANT PHYSIOLOGY 2023; 192:789-804. [PMID: 36960590 PMCID: PMC10231464 DOI: 10.1093/plphys/kiad185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 06/01/2023]
Abstract
Photosynthetic organisms frequently experience abiotic stress that restricts their growth and development. Under such circumstances, most absorbed solar energy cannot be used for CO2 fixation and can cause the photoproduction of reactive oxygen species (ROS) that can damage the photosynthetic reaction centers of PSI and PSII, resulting in a decline in primary productivity. This work describes a biological "switch" in the green alga Chlamydomonas reinhardtii that reversibly restricts photosynthetic electron transport (PET) at the cytochrome b6f (Cyt b6f) complex when the capacity for accepting electrons downstream of PSI is severely limited. We specifically show this restriction in STARCHLESS6 (sta6) mutant cells, which cannot synthesize starch when they are limited for nitrogen (growth inhibition) and subjected to a dark-to-light transition. This restriction represents a form of photosynthetic control that causes diminished electron flow to PSI and thereby prevents PSI photodamage but does not appear to rely on a ΔpH. Furthermore, when electron flow is restricted, the plastid alternative oxidase (PTOX) becomes active, functioning as an electron valve that dissipates some excitation energy absorbed by PSII and allows the formation of a proton motive force (PMF) that would drive some ATP production (potentially sustaining PSII repair and nonphotochemical quenching [NPQ]). The restriction at the Cyt b6f complex can be gradually relieved with continued illumination. This study provides insights into how PET responds to a marked reduction in availability of downstream electron acceptors and the protective mechanisms involved.
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Affiliation(s)
- Shai Saroussi
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Petra Redekop
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Devin A J Karns
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO 80401, USA
| | - Dylan C Thomas
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO 80401, USA
| | - Tyler M Wittkopp
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA 94305, USA
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Matthew C Posewitz
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO 80401, USA
| | - Arthur R Grossman
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA 94305, USA
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3
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Li L, Lavell A, Meng X, Berkowitz O, Selinski J, van de Meene A, Carrie C, Benning C, Whelan J, De Clercq I, Wang Y. Arabidopsis DGD1 SUPPRESSOR1 Is a Subunit of the Mitochondrial Contact Site and Cristae Organizing System and Affects Mitochondrial Biogenesis. THE PLANT CELL 2019; 31:1856-1878. [PMID: 31118221 PMCID: PMC6713299 DOI: 10.1105/tpc.18.00885] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 04/15/2019] [Accepted: 05/09/2019] [Indexed: 05/04/2023]
Abstract
Mitochondrial and plastid biogenesis requires the biosynthesis and assembly of proteins, nucleic acids, and lipids. In Arabidopsis (Arabidopsis thaliana), the mitochondrial outer membrane protein DGD1 SUPPRESSOR1 (DGS1) is part of a large multi-subunit protein complex that contains the mitochondrial contact site and cristae organizing system 60-kD subunit, the translocase of outer mitochondrial membrane 40-kD subunit (TOM40), the TOM20s, and the Rieske FeS protein. A point mutation in DGS1, dgs1-1, altered the stability and protease accessibility of this complex. This altered mitochondrial biogenesis, mitochondrial size, lipid content and composition, protein import, and respiratory capacity. Whole plant physiology was affected in the dgs1-1 mutant as evidenced by tolerance to imposed drought stress and altered transcriptional responses of markers of mitochondrial retrograde signaling. Putative orthologs of Arabidopsis DGS1 are conserved in eukaryotes, including the Nuclear Control of ATP Synthase2 (NCA2) protein in yeast (Saccharomyces cerevisiae), but lost in Metazoa. The genes encoding DGS1 and NCA2 are part of a similar coexpression network including genes encoding proteins involved in mitochondrial fission, morphology, and lipid homeostasis. Thus, DGS1 links mitochondrial protein and lipid import with cellular lipid homeostasis and whole plant stress responses.
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Affiliation(s)
- Lu Li
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
| | - Anastasiya Lavell
- MSU-DOE Plant Research Laboratory and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Xiangxiang Meng
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
| | - Oliver Berkowitz
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
| | - Jennifer Selinski
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
| | | | - Chris Carrie
- Department Biologie I - Botanik, Ludwig-Maximilians-Universität München, Großhadernerstrasse 2-4, Planegg-Martinsried, 82152, Germany
| | - Christoph Benning
- MSU-DOE Plant Research Laboratory and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - James Whelan
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
| | - Inge De Clercq
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
| | - Yan Wang
- Department of Animal, Plant and Soil Science, School of Life Science, Australian Research Council Centre of Excellence in Plant Energy Biology, La Trobe University, 5 Ring Road, Bundoora, 3086, Victoria, Australia
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4
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Lavell AA, Benning C. Cellular Organization and Regulation of Plant Glycerolipid Metabolism. PLANT & CELL PHYSIOLOGY 2019; 60:1176-1183. [PMID: 30690552 PMCID: PMC6553661 DOI: 10.1093/pcp/pcz016] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Accepted: 01/14/2019] [Indexed: 05/07/2023]
Abstract
Great strides have been made in understanding how membranes and lipid droplets are formed and maintained in land plants, yet much more is to be learned given the complexity of plant lipid metabolism. A complicating factor is the multi-organellar presence of biosynthetic enzymes and unique compositional requirements of different membrane systems. This necessitates a rich network of transporters and transport mechanisms that supply fatty acids, membrane lipids and storage lipids to their final cellular destination. Though we know a large number of the biosynthetic enzymes involved in lipid biosynthesis and a few transport proteins, the regulatory mechanisms, in particular, coordinating expression and/or activity of the majority remain yet to be described. Plants undergoing stress alter their membranes' compositions, and lipids such as phosphatidic acid have been implicated in stress signaling. Additionally, lipid metabolism in chloroplasts supplies precursors for jasmonic acid (JA) biosynthesis, and perturbations in lipid homeostasis has consequences on JA signaling. In this review, several aspects of plant lipid metabolism are discussed that are currently under investigation: cellular transport of lipids, regulation of lipid biosynthesis, roles of lipids in stress signaling, and lastly the structural and oligomeric states of lipid enzymes.
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Affiliation(s)
- A A Lavell
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - C Benning
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
- Corresponding author: E-mail, ; Fax, 517-353-9168
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Van Dingenen J, Blomme J, Gonzalez N, Inzé D. Plants grow with a little help from their organelle friends. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:6267-6281. [PMID: 27815330 DOI: 10.1093/jxb/erw399] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Chloroplasts and mitochondria are indispensable for plant development. They not only provide energy and carbon sources to cells, but also have evolved to become major players in a variety of processes such as amino acid metabolism, hormone biosynthesis and cellular signalling. As semi-autonomous organelles, they contain a small genome that relies largely on nuclear factors for its maintenance and expression. An intensive crosstalk between the nucleus and the organelles is therefore essential to ensure proper functioning, and the nuclear genes encoding organellar proteins involved in photosynthesis and oxidative phosphorylation are obviously crucial for plant growth. Organ growth is determined by two main cellular processes: cell proliferation and cell expansion. Here, we review how plant growth is affected in mutants of organellar proteins that are differentially expressed during leaf and root development. Our findings indicate a clear role for organellar proteins in plant organ growth, primarily during cell proliferation. However, to date, the role of the nuclear-encoded organellar proteins in the cellular processes driving organ growth has not been investigated in much detail. We therefore encourage researchers to extend their phenotypic characterization beyond macroscopic features in order to get a better view on how chloroplasts and mitochondria regulate the basic processes of cell proliferation and cell expansion, essential to driving growth.
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Affiliation(s)
- Judith Van Dingenen
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Jonas Blomme
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Nathalie Gonzalez
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
| | - Dirk Inzé
- Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
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Hori K, Nobusawa T, Watanabe T, Madoka Y, Suzuki H, Shibata D, Shimojima M, Ohta H. Tangled evolutionary processes with commonality and diversity in plastidial glycolipid synthesis in photosynthetic organisms. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1294-1308. [PMID: 27108062 DOI: 10.1016/j.bbalip.2016.04.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 04/09/2016] [Accepted: 04/15/2016] [Indexed: 01/25/2023]
Abstract
In photosynthetic organisms, the photosynthetic membrane constitutes a scaffold for light-harvesting complexes and photosynthetic reaction centers. Three kinds of glycolipids, namely monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and sulfoquinovosyldiacylglycerol, constitute approximately 80-90% of photosynthetic membrane lipids and are well conserved from tiny cyanobacteria to the leaves of huge trees. These glycolipids perform a wide variety of functions beyond biological membrane formation. In particular, the capability of adaptation to harsh environments through regulation of membrane glycolipid composition is essential for healthy growth and development of photosynthetic organisms. The genome analysis and functional genetics of the model seed plant Arabidopsis thaliana have yielded many new findings concerning the biosynthesis, regulation, and functions of glycolipids. Nevertheless, it remains to be clarified how the complex biosynthetic pathways and well-organized functions of glycolipids evolved in early and primitive photosynthetic organisms, such as cyanobacteria, to yield modern photosynthetic organisms like land plants. Recently, genome data for many photosynthetic organisms have been made available as the fruit of the rapid development of sequencing technology. We also have reported the draft genome sequence of the charophyte alga Klebsormidium flaccidum, which is an intermediate organism between green algae and land plants. Here, we performed a comprehensive phylogenic analysis of glycolipid biosynthesis genes in oxygenic photosynthetic organisms including K. flaccidum. Based on the results together with membrane lipid analysis of this alga, we discuss the evolution of glycolipid synthesis in photosynthetic organisms. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
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Affiliation(s)
- Koichi Hori
- Tokyo Institute of Technology, School of Life Science and Technology, Yokohama City, Kanagawa 226-8501, Japan; CREST, Japan Science and Technology Agency, Japan
| | - Takashi Nobusawa
- Tokyo Institute of Technology, School of Life Science and Technology, Yokohama City, Kanagawa 226-8501, Japan; CREST, Japan Science and Technology Agency, Japan
| | - Tei Watanabe
- Tokyo Institute of Technology, Graduate School of Bioscience and Biotechnology, Yokohama City, Kanagawa 226-8501, Japan
| | - Yuka Madoka
- Tokyo Institute of Technology, School of Life Science and Technology, Yokohama City, Kanagawa 226-8501, Japan
| | - Hideyuki Suzuki
- Kazusa DNA Research Institute, 2-6-7 Kazusa-kamatari, Kisarazu, Chiba 292-0818, Japan
| | - Daisuke Shibata
- Kazusa DNA Research Institute, 2-6-7 Kazusa-kamatari, Kisarazu, Chiba 292-0818, Japan
| | - Mie Shimojima
- Tokyo Institute of Technology, School of Life Science and Technology, Yokohama City, Kanagawa 226-8501, Japan
| | - Hiroyuki Ohta
- Tokyo Institute of Technology, School of Life Science and Technology, Yokohama City, Kanagawa 226-8501, Japan; CREST, Japan Science and Technology Agency, Japan; Tokyo Institute of Technology, Earth-Life Science Institute, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan.
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7
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Bobik K, Burch-Smith TM. Chloroplast signaling within, between and beyond cells. FRONTIERS IN PLANT SCIENCE 2015; 6:781. [PMID: 26500659 PMCID: PMC4593955 DOI: 10.3389/fpls.2015.00781] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/10/2015] [Indexed: 05/18/2023]
Abstract
The most conspicuous function of plastids is the oxygenic photosynthesis of chloroplasts, yet plastids are super-factories that produce a plethora of compounds that are indispensable for proper plant physiology and development. Given their origins as free-living prokaryotes, it is not surprising that plastids possess their own genomes whose expression is essential to plastid function. This semi-autonomous character of plastids requires the existence of sophisticated regulatory mechanisms that provide reliable communication between them and other cellular compartments. Such intracellular signaling is necessary for coordinating whole-cell responses to constantly varying environmental cues and cellular metabolic needs. This is achieved by plastids acting as receivers and transmitters of specific signals that coordinate expression of the nuclear and plastid genomes according to particular needs. In this review we will consider the so-called retrograde signaling occurring between plastids and nuclei, and between plastids and other organelles. Another important role of the plastid we will discuss is the involvement of plastid signaling in biotic and abiotic stress that, in addition to influencing retrograde signaling, has direct effects on several cellular compartments including the cell wall. We will also review recent evidence pointing to an intriguing function of chloroplasts in regulating intercellular symplasmic transport. Finally, we consider an intriguing yet less widely known aspect of plant biology, chloroplast signaling from the perspective of the entire plant. Thus, accumulating evidence highlights that chloroplasts, with their complex signaling pathways, provide a mechanism for exquisite regulation of plant development, metabolism and responses to the environment. As chloroplast processes are targeted for engineering for improved productivity the effect of such modifications on chloroplast signaling will have to be carefully considered in order to avoid unintended consequences on plant growth and development.
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Affiliation(s)
| | - Tessa M. Burch-Smith
- *Correspondence: Tessa M. Burch-Smith, Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, 1414 Cumberland Avenue, M407 Walters Life Science, Knoxville, TN 37932, USA,
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8
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Abstract
Coherent Raman scattering (CRS) microscopy is a label-free method for chemical imaging, as it offers chemical specificity with orders of magnitude better sensitivity than the state-of-the-art confocal Raman scattering microscopy. Currently CRS technique includes coherent anti-Stokes Raman scattering (CARS), and stimulated Raman scattering (SRS). This chapter describes the methods of using CRS microscopy to image major polymers in plant cell wall (i.e., lignin and cellulose). This method can also be used to real-time monitor the chemical processes involved in biomass pretreatment. These together demonstrate CRS as an effective method for imaging complex chemistry in biological systems.
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Affiliation(s)
- Yining Zeng
- Biosciences Center National Renewable Energy Laboratory, BioEnergy Science Center, Golden, CO, USA.
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9
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Duncan O, Taylor NL, Carrie C, Eubel H, Kubiszewski-Jakubiak S, Zhang B, Narsai R, Millar AH, Whelan J. Multiple lines of evidence localize signaling, morphology, and lipid biosynthesis machinery to the mitochondrial outer membrane of Arabidopsis. PLANT PHYSIOLOGY 2011; 157:1093-113. [PMID: 21896887 PMCID: PMC3252152 DOI: 10.1104/pp.111.183160] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2011] [Accepted: 08/31/2011] [Indexed: 05/18/2023]
Abstract
The composition of the mitochondrial outer membrane is notoriously difficult to deduce by orthology to other organisms, and biochemical enrichments are inevitably contaminated with the closely associated inner mitochondrial membrane and endoplasmic reticulum. In order to identify novel proteins of the outer mitochondrial membrane in Arabidopsis (Arabidopsis thaliana), we integrated a quantitative mass spectrometry analysis of highly enriched and prefractionated samples with a number of confirmatory biochemical and cell biology approaches. This approach identified 42 proteins, 27 of which were novel, more than doubling the number of confirmed outer membrane proteins in plant mitochondria and suggesting novel functions for the plant outer mitochondrial membrane. The novel components identified included proteins that affected mitochondrial morphology and/or segregation, a protein that suggests the presence of bacterial type lipid A in the outer membrane, highly stress-inducible proteins, as well as proteins necessary for embryo development and several of unknown function. Additionally, proteins previously inferred via orthology to be present in other compartments, such as an NADH:cytochrome B5 reductase required for hydroxyl fatty acid accumulation in developing seeds, were shown to be located in the outer membrane. These results also revealed novel proteins, which may have evolved to fulfill plant-specific requirements of the mitochondrial outer membrane, and provide a basis for the future functional characterization of these proteins in the context of mitochondrial intracellular interaction.
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Lü S, Zhao H, Parsons EP, Xu C, Kosma DK, Xu X, Chao D, Lohrey G, Bangarusamy DK, Wang G, Bressan RA, Jenks MA. The glossyhead1 allele of ACC1 reveals a principal role for multidomain acetyl-coenzyme A carboxylase in the biosynthesis of cuticular waxes by Arabidopsis. PLANT PHYSIOLOGY 2011; 157:1079-92. [PMID: 21949210 PMCID: PMC3252135 DOI: 10.1104/pp.111.185132] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A novel mutant of Arabidopsis (Arabidopsis thaliana), having highly glossy inflorescence stems, postgenital fusion in floral organs, and reduced fertility, was isolated from an ethyl methanesulfonate-mutagenized population and designated glossyhead1 (gsd1). The gsd1 locus was mapped to chromosome 1, and the causal gene was identified as a new allele of Acetyl-Coenzyme A Carboxylase1 (ACC1), a gene encoding the main enzyme in cytosolic malonyl-coenzyme A synthesis. This, to our knowledge, is the first mutant allele of ACC1 that does not cause lethality at the seed or early germination stage, allowing for the first time a detailed analysis of ACC1 function in mature tissues. Broad lipid profiling of mature gsd1 organs revealed a primary role for ACC1 in the biosynthesis of the very-long-chain fatty acids (C(20:0) or longer) associated with cuticular waxes and triacylglycerols. Unexpectedly, transcriptome analysis revealed that gsd1 has limited impact on any lipid metabolic networks but instead has a large effect on environmental stress-responsive pathways, especially senescence and ethylene synthesis determinants, indicating a possible role for the cytosolic malonyl-coenzyme A-derived lipids in stress response signaling.
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Tan X, Wang Q, Tian B, Zhang H, Lu D, Zhou J. A Brassica napus lipase locates at the membrane contact sites involved in chloroplast development. PLoS One 2011; 6:e26831. [PMID: 22046373 PMCID: PMC3202582 DOI: 10.1371/journal.pone.0026831] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 10/05/2011] [Indexed: 11/26/2022] Open
Abstract
Background Fatty acids synthesized in chloroplast are transported to endoplasmic reticulum (ER) for triacylglycerols (TAGs) resembling. The development of chloroplast also requires lipids trafficking from ER to chloroplast. The membrane contact sites (MCSs) between ER and chloroplast has been demonstrated to be involved for the trafficking of lipids and proteins. Lipids trafficking between ER and chloroplast is often accompanied by lipids interconversion. However, it is rarely known how lipids interconversion happens during their trafficking. Methodology/Principal Findings We cloned a lipase gene from Brassica napus L., designated as BnCLIP1. Green fluorescence protein (GFP)-tagged BnCLIP1 was shown to locate at the MCSs between ER and chloroplasts in tobacco leaves. Heterogeneous expression of BnCLIP1 in Saccharomyces cerevisiae (pep4) reduced the total amount of fatty acid. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that the truncated BnCLIP1 had a substrate preference for C16:0 lipids in Saccharomyces cerevisiae (pep4). To probe the physiological function of BnCLIP1, two Brassica napus lines with different oil-content were introduced to investigate the transcript patterns of BnCLIP1 during seed development. Intriguingly, the transcript level of BnCLIP1 was found to be immediately up-regulated during the natural seed senescence of both lines; the transcription response of BnCLIP1 in the high oil-content seeds was faster than the lower ones, suggesting a potential role of BnCLIP1 in affecting seed oil synthesis via regulating chloroplast integrity. Further researches showed that chemical disruption of leaf chloroplast also activated the transcription of BnCLIP1. Conclusions/Significance The findings of this study show that BnCLIP1 encodes a lipase, localizes at the MCSs and involves in chloroplast development.
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Affiliation(s)
- Xiaoli Tan
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Qiuye Wang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Baoxia Tian
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Henan Zhang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Daoli Lu
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
| | - Jia Zhou
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China
- * E-mail:
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12
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Shimojima M, Ohta H. Critical regulation of galactolipid synthesis controls membrane differentiation and remodeling in distinct plant organs and following environmental changes. Prog Lipid Res 2011; 50:258-66. [PMID: 21414359 DOI: 10.1016/j.plipres.2011.03.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/06/2010] [Accepted: 03/04/2011] [Indexed: 01/08/2023]
Abstract
The plant galactolipids, monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), are the most abundant lipids in chloroplast membranes, and they constitute the majority of total membrane lipids in plants. MGDG is synthesized by two types of MGDG synthase, type-A (MGD1) and type-B (MGD2, MGD3). These MGDG synthases have distinct roles in Arabidopsis. In photosynthetic organs, Type A MGD is responsible for the bulk of MGDG synthesis, whereas Type B MGD is expressed in non-photosynthetic organs such as roots and flowers and mainly contributes to DGDG accumulation under phosphate deficiency. Similar to MGDG synthesis, DGDG is synthesized by two synthases, DGD1 and DGD2; DGD1 is responsible for the majority of DGDG synthesis, whereas DGD2 makes its main contribution under phosphate deficiency. These galactolipid synthases are regulated by light, plant hormones, redox state, phosphatidic acid levels, and various stress conditions such as drought and nutrient limitation. Maintaining the appropriate ratio of these two galactolipids in chloroplasts is important for stabilizing thylakoid membranes and maximizing the efficiency of photosynthesis. Here we review progress made in the last decade towards a better understanding of the pathways regulating plant galactolipid biosynthesis.
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Affiliation(s)
- Mie Shimojima
- Center for Biological Resources and Informatics, Tokyo Institute of Technology, 4259-B-65 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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13
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Moellering ER, Benning C. Galactoglycerolipid metabolism under stress: a time for remodeling. TRENDS IN PLANT SCIENCE 2011; 16:98-107. [PMID: 21145779 DOI: 10.1016/j.tplants.2010.11.004] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/08/2010] [Accepted: 11/09/2010] [Indexed: 05/20/2023]
Abstract
Galactoglycerolipids are the predominant lipid building blocks of chloroplast membranes and are essential for plant growth. Plant chloroplasts harbor a constitutive set of UDP-Gal-dependent lipid galactosyltransferases that are responsible for the bulk of galactoglycerolipid biosynthesis. A set of paralogs is induced in response to phosphate deprivation, which leads to the remodeling of extraplastidic membranes with a partial replacement of phosphoglycerolipid by digalactosyldiacylglycerol. A third type of galactoglycerolipid biosynthetic enzyme, a UDP-Gal-independent galactoglycerolipid galactosyltransferase, was recently shown to be involved in freezing tolerance. Here, we look at how understanding of the regulation of galactoglycerolipid biosynthesis in chloroplasts by these multiple enzyme sets is rapidly evolving and discuss the increasingly recognized role of lipid remodeling in response to diverse abiotic stresses.
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Affiliation(s)
- Eric R Moellering
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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14
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Xu C, Moellering ER, Muthan B, Fan J, Benning C. Lipid transport mediated by Arabidopsis TGD proteins is unidirectional from the endoplasmic reticulum to the plastid. PLANT & CELL PHYSIOLOGY 2010; 51:1019-28. [PMID: 20410050 DOI: 10.1093/pcp/pcq053] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The transfer of lipids between the endoplasmic reticulum (ER) and the plastid in Arabidopsis involves the TRIGALACTOSYLDIACYLGLYCEROL (TGD) proteins. Lipid exchange is thought to be bidirectional based on the presence of specific lipid molecular species in Arabidopsis mutants impaired in the desaturation of fatty acids of membrane lipids in the ER and plastid. However, it was unclear whether TGD proteins were required for lipid trafficking in both directions. This question was addressed through the analysis of double mutants of tgd1-1 or tgd4-3 in genetic mutant backgrounds leading to a defect in lipid fatty acid desaturation either in the ER (fad2) or the plastid (fad6). The fad6 tgd1-1 and fad6 tgd4-3 double mutants showed drastic reductions in the relative levels of polyunsaturated fatty acids and of galactolipids. The growth of these plants and the development of photosynthetic membrane systems were severely compromised, suggesting a disruption in the import of polyunsaturated fatty acid-containing lipid species from the ER. Furthermore, a forward-genetic screen in the tgd1-2 dgd1 mutant background led to the isolation of a new fad6-2 allele with a marked reduction in the amount of digalactosyldiacylglycerol. In contrast, the introduction of fad2, affecting fatty acid desaturation of lipids in the ER, into the two tgd mutant backgrounds did not further decrease the level of fatty acid desaturation in lipids of extraplastidic membranes. These results suggest that the role of TGD proteins is limited to plastid lipid import, but does not extend to lipid export from the plastid to extraplastidic membranes.
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Affiliation(s)
- Changcheng Xu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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Abstract
Chloroplasts are the defining organelle of photoautotrophic plant cells. Photosynthetic light reactions and electron transport are the functions of an elaborate thylakoid membrane system inside chloroplasts. The lipid composition of photosynthetic membranes is characterized by a substantial fraction of nonphosphorous galactoglycerolipids reflecting the need of sessile plants to conserve phosphorus. Lipid transport and assembly of glycerolipids play an essential role in the biogenesis of the photosynthetic apparatus in developing chloroplasts. During chloroplast biogenesis, fatty acids are synthesized in the plastid and are exported to the endoplasmic reticulum, where they are incorporated into membrane lipids. Alternatively, lipids can also be assembled de novo at the inner envelope membrane of plastids in many plants. A rich repertoire of lipid exchange mechanisms involving the thylakoid membranes, the chloroplast inner and outer envelope membranes, and the endoplasmic reticulum is emerging. Studies of thylakoid biogenesis provide new insights into the general mechanisms of intermembrane lipid transfer.
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Affiliation(s)
- Christoph Benning
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA.
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Kobayashi K, Nakamura Y, Ohta H. Type A and type B monogalactosyldiacylglycerol synthases are spatially and functionally separated in the plastids of higher plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2009; 47:518-25. [PMID: 19179086 DOI: 10.1016/j.plaphy.2008.12.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Indexed: 05/02/2023]
Abstract
Mono- and digalactosyldiacylglycerol (MGDG and DGDG, respectively) constitute the bulk of membrane lipids in plant chloroplasts. The final step in MGDG biosynthesis occurs in the plastid envelope and is catalyzed by MGDG synthase. In Arabidopsis, the three MGDG synthases are classified into type A (atMGD1) and type B MGD isoforms (atMGD2 and atMGD3). atMGD1 is an inner envelope membrane-associated protein of chloroplasts and is responsible for the bulk of galactolipid biosynthesis in green tissues. MGD1 function is indispensable for thylakoid membrane biogenesis and embryogenesis. By contrast, type B atMGD2 and atMGD3 are localized in the outer envelopes and have no important role in chloroplast biogenesis or plant development under nutrient-sufficient conditions. These type B MGD genes are, however, strongly induced by phosphate (Pi) starvation and are essential for alternative galactolipid biosynthesis during Pi starvation. MGD1 gene expression is up-regulated by light and cytokinins. By contrast, Pi starvation-dependent expression of atMGD2/3 is suppressed by cytokinins but induced through auxin signaling pathways. These growth factors may control the functional sharing of the inner envelope pathway by atMGD1 and the outer envelope pathway by atMGD2/3 according to the growth environment.
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Affiliation(s)
- Koichi Kobayashi
- Department of General Systems Studies, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
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Nakamura Y, Kobayashi K, Ohta H. Activation of galactolipid biosynthesis in development of pistils and pollen tubes. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2009; 47:535-9. [PMID: 19181535 DOI: 10.1016/j.plaphy.2008.12.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 12/22/2008] [Accepted: 12/30/2008] [Indexed: 05/07/2023]
Abstract
Galactolipids such as monogalactosyldiacylglycerol and digalactosyldiacylglycerol are essential lipids for the proper functioning of photosynthetic membranes. However, the function of galactolipids in flowers is unknown. Previously, we reported that pistils have higher galactolipid-producing activity than leaves. The present study investigated galactolipid biosynthesis in pistils in more detail using Petunia hybrida and Lilium longiflorum. The results showed that digalactosyldiacylglycerol levels increased during flower development. In addition, the galactose incorporation activity into galactolipids was induced, suggesting that the pathway for the production of digalactosyldiacylglycerol was stimulated. Interestingly, a significant increase in galactolipids was also observed in elongated pollen tubes. Therefore, pistils are the main site of galactolipid biosynthesis and whose galactolipid biosynthesis activity is induced during flower development, and this induction includes considerable galactolipid biosynthesis in pollen tubes.
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Affiliation(s)
- Yuki Nakamura
- Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, Republic of Singapore
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Kobayashi K, Awai K, Nakamura M, Nagatani A, Masuda T, Ohta H. Type-B monogalactosyldiacylglycerol synthases are involved in phosphate starvation-induced lipid remodeling, and are crucial for low-phosphate adaptation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 57:322-31. [PMID: 18808455 DOI: 10.1111/j.1365-313x.2008.03692.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Mono- and digalactosyldiacylglycerol (MGDG and DGDG, respectively) constitute the bulk of membrane lipids in plant chloroplasts. Mutant analyses in Arabidopsis have shown that these galactolipids are essential for chloroplast biogenesis and photoautotrophic growth. Moreover, these non-phosphorous lipids are proposed to participate in low-phosphate (Pi) adaptations. Under Pi-limited conditions, a drastic accumulation of DGDG occurs concomitantly with a large reduction in membrane phospholipids, suggesting that plants substitute DGDG for phospholipids during Pi starvation. Previously, we reported that among the three MGDG synthase genes (MGD1, MGD2 and MGD3), the type-B MGD2 and MGD3 are upregulated in parallel with DGDG synthase genes during Pi starvation. Here, we describe the identification and characterization of T-DNA insertional mutants of Arabidopsis type-B MGD genes. Under Pi-starved conditions, the mgd3-1 mutant showed a drastic reduction in DGDG accumulation, particularly in the root, indicating that MGD3 is the main isoform responsible for DGDG biosynthesis in Pi-starved roots. Moreover, in the roots of mgd2 mgd3 plants, Pi stress-induced accumulation of DGDG was almost fully abolished, showing that type-B MGD enzymes are essential for membrane lipid remodeling in Pi-starved roots. Reductions in fresh weight, root growth and photosynthetic performance were also observed in these mutants under Pi-starved conditions. These results demonstrate that Pi stress-induced membrane lipid remodeling is important in plant growth during Pi starvation. The widespread distribution of type-B MGD genes in land plants suggests that membrane lipid remodeling mediated by type-B MGD enzymes is a potent adaptation to Pi deficiency for land plants.
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Affiliation(s)
- Koichi Kobayashi
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-65 Nagatsuta-cho, Midori-ku, Yokohama 226 8501, Japan
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Xu C, Fan J, Cornish AJ, Benning C. Lipid trafficking between the endoplasmic reticulum and the plastid in Arabidopsis requires the extraplastidic TGD4 protein. THE PLANT CELL 2008; 20:2190-204. [PMID: 18689504 PMCID: PMC2553622 DOI: 10.1105/tpc.108.061176] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Revised: 07/19/2008] [Accepted: 07/27/2008] [Indexed: 05/18/2023]
Abstract
The development of chloroplasts in Arabidopsis thaliana requires extensive lipid trafficking between the endoplasmic reticulum (ER) and the plastid. The biosynthetic enzymes for the final steps of chloroplast lipid assembly are associated with the plastid envelope membranes. For example, during biosynthesis of the galactoglycerolipids predominant in photosynthetic membranes, galactosyltransferases associated with these membranes transfer galactosyl residues from UDP-Gal to diacylglycerol. In Arabidopsis, diacylglycerol can be derived from the ER or the plastid. Here, we describe a mutant of Arabidopsis, trigalactosyldiacylglycerol4 (tgd4), in which ER-derived diacylglycerol is not available for galactoglycerolipid biosynthesis. This mutant accumulates diagnostic oligogalactoglycerolipids, hence its name, and triacylglycerol in its tissues. The TGD4 gene encodes a protein that appears to be associated with the ER membranes. Mutant ER microsomes show a decreased transfer of lipids to isolated plastids consistent with in vivo labeling data, indicating a disruption of ER-to-plastid lipid transfer. The complex lipid phenotype of the mutant is similar to that of the tgd1,2,3 mutants disrupted in components of a lipid transporter of the inner plastid envelope membrane. However, unlike the TGD1,2,3 complex, which is proposed to transfer phosphatidic acid through the inner envelope membrane, TGD4 appears to be part of the machinery mediating lipid transfer between the ER and the outer plastid envelope membrane. The extent of direct ER-to-plastid envelope contact sites is not altered in the tgd4 mutant. However, this does not preclude a possible function of TGD4 in those contact sites as a conduit for lipid transfer between the ER and the plastid.
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Affiliation(s)
- Changcheng Xu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
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