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Mellon M, Storti M, Vera-Vives AM, Kramer DM, Alboresi A, Morosinotto T. Inactivation of mitochondrial complex I stimulates chloroplast ATPase in Physcomitrium patens. PLANT PHYSIOLOGY 2021; 187:931-946. [PMID: 34608952 PMCID: PMC8491079 DOI: 10.1093/plphys/kiab276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 05/18/2021] [Indexed: 06/11/2023]
Abstract
Light is the ultimate source of energy for photosynthetic organisms, but respiration is fundamental for supporting metabolism during the night or in heterotrophic tissues. In this work, we isolated Physcomitrella (Physcomitrium patens) plants with altered respiration by inactivating Complex I (CI) of the mitochondrial electron transport chain by independently targeting on two essential subunits. Inactivation of CI caused a strong growth impairment even in fully autotrophic conditions in tissues where all cells are photosynthetically active, demonstrating that respiration is essential for photosynthesis. CI mutants showed alterations in the stoichiometry of respiratory complexes while the composition of photosynthetic apparatus was substantially unaffected. CI mutants showed altered photosynthesis with high activity of both Photosystems I and II, likely the result of high chloroplast ATPase activity that led to smaller ΔpH formation across thylakoid membranes, decreasing photosynthetic control on cytochrome b6f in CI mutants. These results demonstrate that alteration of respiratory activity directly impacts photosynthesis in P. patens and that metabolic interaction between organelles is essential in their ability to use light energy for growth.
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Affiliation(s)
- Marco Mellon
- Department of Biology, University of Padova, 35121 Padova, Italy
| | - Mattia Storti
- Department of Biology, University of Padova, 35121 Padova, Italy
| | | | - David M. Kramer
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
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Phua SY, De Smet B, Remacle C, Chan KX, Van Breusegem F. Reactive oxygen species and organellar signaling. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5807-5824. [PMID: 34009340 DOI: 10.1093/jxb/erab218] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 05/14/2021] [Indexed: 05/07/2023]
Abstract
The evolution of photosynthesis and its associated metabolic pathways has been crucial to the successful establishment of plants, but has also challenged plant cells in the form of production of reactive oxygen species (ROS). Intriguingly, multiple forms of ROS are generated in virtually every plant cell compartment through diverse pathways. As a result, a sophisticated network of ROS detoxification and signaling that is simultaneously tailored to individual organelles and safeguards the entire cell is necessary. Here we take an organelle-centric view on the principal sources and sinks of ROS across the plant cell and provide insights into the ROS-induced organelle to nucleus retrograde signaling pathways needed for operational readjustments during environmental stresses.
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Affiliation(s)
- Su Yin Phua
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| | - Barbara De Smet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| | - Claire Remacle
- Genetics and Physiology of Microalgae, InBios/Phytosystems, Université de Liège, Liège,Belgium
| | - Kai Xun Chan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| | - Frank Van Breusegem
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
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3
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Assembly of Mitochondrial Complex I Requires the Low-Complexity Protein AMC1 in Chlamydomonas reinhardtii. Genetics 2020; 214:895-911. [PMID: 32075865 DOI: 10.1534/genetics.120.303029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 02/05/2020] [Indexed: 11/18/2022] Open
Abstract
Complex I is the first enzyme involved in the mitochondrial electron transport chain. With >40 subunits of dual genetic origin, the biogenesis of complex I is highly intricate and poorly understood. We used Chlamydomonas reinhardtii as a model system to reveal factors involved in complex I biogenesis. Two insertional mutants, displaying a complex I assembly defect characterized by the accumulation of a 700 kDa subcomplex, were analyzed. Genetic analyses showed these mutations were allelic and mapped to the gene AMC1 (Cre16.g688900) encoding a low-complexity protein of unknown function. The complex I assembly and activity in the mutant was restored by complementation with the wild-type gene, confirming AMC1 is required for complex I biogenesis. The N terminus of AMC1 targets a reporter protein to yeast mitochondria, implying that AMC1 resides and functions in the Chlamydomonas mitochondria. Accordingly, in both mutants, loss of AMC1 function results in decreased abundance of the mitochondrial nd4 transcript, which encodes the ND4 membrane subunit of complex I. Loss of ND4 in a mitochondrial nd4 mutant is characterized by a membrane arm assembly defect, similar to that exhibited by loss of AMC1. These results suggest AMC1 is required for the production of mitochondrially-encoded complex I subunits, specifically ND4. We discuss the possible modes of action of AMC1 in mitochondrial gene expression and complex I biogenesis.
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Subrahmanian N, Castonguay AD, Fatnes TA, Hamel PP. Chlamydomonas reinhardtii as a plant model system to study mitochondrial complex I dysfunction. PLANT DIRECT 2020; 4:e00200. [PMID: 32025618 PMCID: PMC6996877 DOI: 10.1002/pld3.200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/13/2019] [Accepted: 01/06/2020] [Indexed: 06/10/2023]
Abstract
Mitochondrial complex I, a proton-pumping NADH: ubiquinone oxidoreductase, is required for oxidative phosphorylation. However, the contribution of several human mutations to complex I deficiency is poorly understood. The unicellular alga Chlamydomonas reinhardtii was utilized to study complex I as, unlike in mammals, mutants with complete loss of the holoenzyme are viable. From a forward genetic screen for complex I-deficient insertional mutants, six mutants exhibiting complex I deficiency with assembly defects were isolated. Chlamydomonas mutants isolated from our screens, lacking the subunits NDUFV2 and NDUFB10, were used to reconstruct and analyze the effect of two human mutations in these subunit-encoding genes. The K209R substitution in NDUFV2, reported in Parkinson's disease patients, did not significantly affect the enzyme activity or assembly. The C107S substitution in the NDUFB10 subunit, reported in a case of fatal infantile cardiomyopathy, is part of a conserved C-(X)11-C motif. The cysteine substitutions, at either one or both positions, still allowed low levels of holoenzyme formation, indicating that this motif is crucial for complex I function but not strictly essential for assembly. We show that the algal mutants provide a simple and useful platform to delineate the consequences of patient mutations on complex I function.
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Affiliation(s)
- Nitya Subrahmanian
- Department of Molecular GeneticsThe Ohio State UniversityColumbusOHUSA
- Plant Cellular and Molecular Biology Graduate ProgramThe Ohio State UniversityColumbusOHUSA
| | - Andrew David Castonguay
- Department of Molecular GeneticsThe Ohio State UniversityColumbusOHUSA
- Molecular Genetics Graduate ProgramThe Ohio State UniversityColumbusOHUSA
| | - Thea Aspelund Fatnes
- Department of Molecular GeneticsThe Ohio State UniversityColumbusOHUSA
- Present address:
Fürst Medical LaboratoryOsloNorway
| | - Patrice Paul Hamel
- Department of Molecular GeneticsThe Ohio State UniversityColumbusOHUSA
- Department of Biological Chemistry and PharmacologyThe Ohio State UniversityColumbusOHUSA
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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: 162] [Impact Index Per Article: 32.4] [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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Larosa V, Remacle C. Insights into the respiratory chain and oxidative stress. Biosci Rep 2018; 38:BSR20171492. [PMID: 30201689 PMCID: PMC6167499 DOI: 10.1042/bsr20171492] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 08/15/2018] [Accepted: 09/05/2018] [Indexed: 01/13/2023] Open
Abstract
Reactive oxygen species (ROS) are highly reactive reduced oxygen molecules that result from aerobic metabolism. The common forms are the superoxide anion (O2∙-) and hydrogen peroxide (H2O2) and their derived forms, hydroxyl radical (HO∙) and hydroperoxyl radical (HOO∙). Their production sites in mitochondria are reviewed. Even though being highly toxic products, ROS seem important in transducing information from dysfunctional mitochondria. Evidences of signal transduction mediated by ROS in mitochondrial deficiency contexts are then presented in different organisms such as yeast, mammals or photosynthetic organisms.
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Affiliation(s)
- Véronique Larosa
- Genetics and Physiology of Microalgae, UR InBios/Phytosystems, Chemin de la Vallée, 4, University of Liège, Liège 4000, Belgium
| | - Claire Remacle
- Genetics and Physiology of Microalgae, UR InBios/Phytosystems, Chemin de la Vallée, 4, University of Liège, Liège 4000, Belgium
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7
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Massoz S, Hanikenne M, Bailleul B, Coosemans N, Radoux M, Miranda-Astudillo H, Cardol P, Larosa V, Remacle C. In vivo chlorophyll fluorescence screening allows the isolation of a Chlamydomonas mutant defective for NDUFAF3, an assembly factor involved in mitochondrial complex I assembly. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:584-595. [PMID: 28857403 DOI: 10.1111/tpj.13677] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 08/11/2017] [Accepted: 08/21/2017] [Indexed: 05/16/2023]
Abstract
The qualitative screening method used to select complex I mutants in the microalga Chlamydomonas, based on reduced growth under heterotrophic conditions, is not suitable for high-throughput screening. In order to develop a fast screening method based on measurements of chlorophyll fluorescence, we first demonstrated that complex I mutants displayed decreased photosystem II efficiency in the genetic background of a photosynthetic mutation leading to reduced formation of the electrochemical proton gradient in the chloroplast (pgrl1 mutation). In contrast, single mutants (complex I and pgrl1 mutants) could not be distinguished from the wild type by their photosystem II efficiency under the conditions tested. We next performed insertional mutagenesis on the pgrl1 mutant. Out of about 3000 hygromycin-resistant insertional transformants, 46 had decreased photosystem II efficiency and three were complex I mutants. One of the mutants was tagged and whole genome sequencing identified the resistance cassette in NDUFAF3, a homolog of the human NDUFAF3 gene, encoding for an assembly factor involved in complex I assembly. Complemented strains showed restored complex I activity and assembly. Overall, we describe here a screening method which is fast and particularly suited for the identification of Chlamydomonas complex I mutants.
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Affiliation(s)
- Simon Massoz
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Marc Hanikenne
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- InBioS - Functional Genomics and Plant Molecular Imaging, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Benjamin Bailleul
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Nadine Coosemans
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Michèle Radoux
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Hector Miranda-Astudillo
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Pierre Cardol
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Véronique Larosa
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
| | - Claire Remacle
- InBioS - Genetics and Physiology of Microalgae, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
- PhytoSYSTEMS, Chemin de la vallée, 4, 4000 Liège, University of Liège, Belgium
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8
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Imam S, Schäuble S, Valenzuela J, de Lomana ALG, Carter W, Price ND, Baliga NS. A refined genome-scale reconstruction of Chlamydomonas metabolism provides a platform for systems-level analyses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 84:1239-56. [PMID: 26485611 PMCID: PMC4715634 DOI: 10.1111/tpj.13059] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 09/30/2015] [Accepted: 10/09/2015] [Indexed: 05/11/2023]
Abstract
Microalgae have reemerged as organisms of prime biotechnological interest due to their ability to synthesize a suite of valuable chemicals. To harness the capabilities of these organisms, we need a comprehensive systems-level understanding of their metabolism, which can be fundamentally achieved through large-scale mechanistic models of metabolism. In this study, we present a revised and significantly improved genome-scale metabolic model for the widely-studied microalga, Chlamydomonas reinhardtii. The model, iCre1355, represents a major advance over previous models, both in content and predictive power. iCre1355 encompasses a broad range of metabolic functions encoded across the nuclear, chloroplast and mitochondrial genomes accounting for 1355 genes (1460 transcripts), 2394 and 1133 metabolites. We found improved performance over the previous metabolic model based on comparisons of predictive accuracy across 306 phenotypes (from 81 mutants), lipid yield analysis and growth rates derived from chemostat-grown cells (under three conditions). Measurement of macronutrient uptake revealed carbon and phosphate to be good predictors of growth rate, while nitrogen consumption appeared to be in excess. We analyzed high-resolution time series transcriptomics data using iCre1355 to uncover dynamic pathway-level changes that occur in response to nitrogen starvation and changes in light intensity. This approach enabled accurate prediction of growth rates, the cessation of growth and accumulation of triacylglycerols during nitrogen starvation, and the temporal response of different growth-associated pathways to increased light intensity. Thus, iCre1355 represents an experimentally validated genome-scale reconstruction of C. reinhardtii metabolism that should serve as a useful resource for studying the metabolic processes of this and related microalgae.
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Affiliation(s)
- Saheed Imam
- Institute for Systems Biology, Seattle, WA, USA
| | - Sascha Schäuble
- Institute for Systems Biology, Seattle, WA, USA
- Jena University Language & Information Engineering (JULIE) Lab, Friedrich-Schiller-University Jena, Jena, Germany
- Research Group Theoretical Systems Biology, Friedrich-Schiller-University Jena, 07743 Jena, Germany
| | | | | | | | - Nathan D. Price
- Institute for Systems Biology, Seattle, WA, USA
- Departments of Bioengineering and Computer Science & Engineering, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
| | - Nitin S. Baliga
- Institute for Systems Biology, Seattle, WA, USA
- Departments of Biology and Microbiology, University of Washington, Seattle, WA, USA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
- Lawrence Berkeley National Lab, Berkeley, CA
- Correspondence: Nitin S. Baliga, Institute for Systems Biology, 401 Terry Ave N., Seattle, WA 98109, Telephone: 206.732.1266, Fax: 206.732.1299,
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9
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Yang W, Catalanotti C, Wittkopp TM, Posewitz MC, Grossman AR. Algae after dark: mechanisms to cope with anoxic/hypoxic conditions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:481-503. [PMID: 25752440 DOI: 10.1111/tpj.12823] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 02/28/2015] [Accepted: 03/03/2015] [Indexed: 06/04/2023]
Abstract
Chlamydomonas reinhardtii is a unicellular, soil-dwelling (and aquatic) green alga that has significant metabolic flexibility for balancing redox equivalents and generating ATP when it experiences hypoxic/anoxic conditions. The diversity of pathways available to ferment sugars is often revealed in mutants in which the activities of specific branches of fermentative metabolism have been eliminated; compensatory pathways that have little activity in parental strains under standard laboratory fermentative conditions are often activated. The ways in which these pathways are regulated and integrated have not been extensively explored. In this review, we primarily discuss the intricacies of dark anoxic metabolism in Chlamydomonas, but also discuss aspects of dark oxic metabolism, the utilization of acetate, and the relatively uncharacterized but critical interactions that link chloroplastic and mitochondrial metabolic networks.
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Affiliation(s)
- Wenqiang Yang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Claudia Catalanotti
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Tyler M Wittkopp
- Department of Plant Biology, 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, Carnegie Institution for Science, Stanford, CA, 94305, USA
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10
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Massoz S, Larosa V, Plancke C, Lapaille M, Bailleul B, Pirotte D, Radoux M, Leprince P, Coosemans N, Matagne RF, Remacle C, Cardol P. Inactivation of genes coding for mitochondrial Nd7 and Nd9 complex I subunits in Chlamydomonas reinhardtii. Impact of complex I loss on respiration and energetic metabolism. Mitochondrion 2014; 19 Pt B:365-74. [DOI: 10.1016/j.mito.2013.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 11/22/2013] [Accepted: 11/26/2013] [Indexed: 02/04/2023]
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Improving the sunlight-to-biomass conversion efficiency in microalgal biofactories. J Biotechnol 2014; 201:28-42. [PMID: 25160918 DOI: 10.1016/j.jbiotec.2014.08.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 07/31/2014] [Accepted: 08/18/2014] [Indexed: 12/31/2022]
Abstract
Microalgae represent promising organisms for the sustainable production of commodities, chemicals or fuels. Future use of such systems, however, requires increased productivity of microalgal mass cultures in order to reach an economic viability for microalgae-based production schemes. The efficiency of sunlight-to-biomass conversion that can be observed in bulk cultures is generally far lower (35-80%) than the theoretical maximum, because energy losses occur at multiple steps during the light-driven conversion of carbon dioxide to organic carbon. The light-harvesting system is a major source of energy losses and thus a prime target for strain engineering. Truncation of the light-harvesting antenna in the algal model organism Chlamydomonas reinhardtii was shown to be an effective way of increasing culture productivity at least under saturating light conditions. Furthermore engineering of the Calvin-Benson cycle or the creation of photorespiratory bypasses in A. thaliana proved to be successful in terms of achieving higher biomass productivities. An efficient generation of novel microalgal strains with improved sunlight conversion efficiencies by targeted engineering in the future will require an expanded molecular toolkit. In the meantime random mutagenesis coupled to high-throughput screening for desired phenotypes can be used to provide engineered microalgae.
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Salinas T, Larosa V, Cardol P, Maréchal-Drouard L, Remacle C. Respiratory-deficient mutants of the unicellular green alga Chlamydomonas: a review. Biochimie 2013; 100:207-18. [PMID: 24139906 DOI: 10.1016/j.biochi.2013.10.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 10/08/2013] [Indexed: 12/28/2022]
Abstract
Genetic manipulation of the unicellular green alga Chlamydomonas reinhardtii is straightforward. Nuclear genes can be interrupted by insertional mutagenesis or targeted by RNA interference whereas random or site-directed mutagenesis allows the introduction of mutations in the mitochondrial genome. This, combined with a screen that easily allows discriminating respiratory-deficient mutants, makes Chlamydomonas a model system of choice to study mitochondria biology in photosynthetic organisms. Since the first description of Chlamydomonas respiratory-deficient mutants in 1977 by random mutagenesis, many other mutants affected in mitochondrial components have been characterized. These respiratory-deficient mutants increased our knowledge on function and assembly of the respiratory enzyme complexes. More recently some of these mutants allowed the study of mitochondrial gene expression processes poorly understood in Chlamydomonas. In this review, we update the data concerning the respiratory components with a special focus on the assembly factors identified on other organisms. In addition, we make an inventory of different mitochondrial respiratory mutants that are inactivated either on mitochondrial or nuclear genes.
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Affiliation(s)
- Thalia Salinas
- Institut de Biologie Moléculaire des Plantes, UPR CNRS 2357, Associated with Université de Strasbourg, 67084 Strasbourg Cedex, France
| | - Véronique Larosa
- Génétique des Microorganismes, Département de Sciences de la Vie, Institut de Botanique, B22, Université de Liège, B-4000 Liège, Belgium
| | - Pierre Cardol
- Génétique des Microorganismes, Département de Sciences de la Vie, Institut de Botanique, B22, Université de Liège, B-4000 Liège, Belgium
| | - Laurence Maréchal-Drouard
- Institut de Biologie Moléculaire des Plantes, UPR CNRS 2357, Associated with Université de Strasbourg, 67084 Strasbourg Cedex, France
| | - Claire Remacle
- Génétique des Microorganismes, Département de Sciences de la Vie, Institut de Botanique, B22, Université de Liège, B-4000 Liège, Belgium.
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13
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Xu L, Law SR, Murcha MW, Whelan J, Carrie C. The dual targeting ability of type II NAD(P)H dehydrogenases arose early in land plant evolution. BMC PLANT BIOLOGY 2013; 13:100. [PMID: 23841539 PMCID: PMC3716789 DOI: 10.1186/1471-2229-13-100] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 07/08/2013] [Indexed: 05/20/2023]
Abstract
BACKGROUND Type II NAD(PH) dehydrogenases are located on the inner mitochondrial membrane of plants, fungi, protists and some primitive animals. However, recent observations have been made which identify several Arabidopsis type II dehydrogenases as dual targeted proteins. Targeting either mitochondria and peroxisomes or mitochondria and chloroplasts. RESULTS Members of the ND protein family were identified in various plant species. Phylogenetic analyses and subcellular targeting predictions were carried out for all proteins. All ND proteins from three model plant species Arabidopsis, rice and Physcomitrella were cloned as N- and C-terminal GFP fusions and subcellular localisations were determined. Dual targeting of plant type II dehydrogenases was observed to have evolved early in plant evolution and to be widespread throughout different plant species. In all three species tested dual targeting to both mitochondria and peroxisomes was found for at least one NDA and NDB type protein. In addition two NDB type proteins from Physcomitrella were also found to target chloroplasts. The dual targeting of NDC type proteins was found to have evolved later in plant evolution. CONCLUSIONS The functions of type II dehydrogenases within plant cells will have to be re-evaluated in light of this newly identified subcellular targeting information.
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Affiliation(s)
- Lin Xu
- ARC Centre of Excellence in Plant Energy Biology, Bayliss Building M316 University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia
| | - Simon R Law
- ARC Centre of Excellence in Plant Energy Biology, Bayliss Building M316 University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia
| | - Monika W Murcha
- ARC Centre of Excellence in Plant Energy Biology, Bayliss Building M316 University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia
| | - James Whelan
- ARC Centre of Excellence in Plant Energy Biology, Bayliss Building M316 University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia
| | - Chris Carrie
- Department of Biology I, Botany, Ludwig-Maximilians Universität München, Großhaderner Strasse 2-4, Planegg-Martinsried, D-82152, Germany
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