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Sun X, LaVoie M, Lefebvre PA, Gallaher SD, Glaesener AG, Strenkert D, Mehta R, Merchant SS, Silflow CD. Mutation of negative regulatory gene CEHC1 encoding an FBXO3 protein results in normoxic expression of HYDA genes in Chlamydomonas reinhardtii. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.22.586359. [PMID: 38586028 PMCID: PMC10996464 DOI: 10.1101/2024.03.22.586359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Oxygen is known to prevent hydrogen production in Chlamydomonas, both by inhibiting the hydrogenase enzyme and by preventing the accumulation of HYDA-encoding transcripts. We developed a screen for mutants showing constitutive accumulation of HYDA1 transcripts in the presence of oxygen. A reporter gene required for ciliary motility, placed under the control of the HYDA1 promoter, conferred motility only in hypoxic conditions. By selecting for mutants able to swim even in the presence of oxygen we obtained strains that express the reporter gene constitutively. One mutant identified a gene encoding an F-box only protein 3 (FBXO3), known to participate in ubiquitylation and proteasomal degradation pathways in other eukaryotes. Transcriptome profiles revealed that the mutation, termed cehc1-1 , leads to constitutive expression of HYDA1 and other genes regulated by hypoxia, and of many genes known to be targets of CRR1, a transcription factor in the nutritional copper signaling pathway. CRR1 was required for the constitutive expression of the HYDA1 reporter gene in cehc1-1 mutants. The CRR1 protein, which is normally degraded in Cu-supplemented cells, was stabilized in cehc1-1 cells, supporting the conclusion that CEHC1 acts to facilitate the degradation of CRR1. Our results reveal a novel negative regulator in the CRR1 pathway and possibly other pathways leading to complex metabolic changes associated with response to hypoxia.
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Li H, Akella S, Engstler C, Omini JJ, Rodriguez M, Obata T, Carrie C, Cerutti H, Mower JP. Recurrent evolutionary switches of mitochondrial cytochrome c maturation systems in Archaeplastida. Nat Commun 2024; 15:1548. [PMID: 38378784 PMCID: PMC10879542 DOI: 10.1038/s41467-024-45813-y] [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: 06/15/2023] [Accepted: 02/05/2024] [Indexed: 02/22/2024] Open
Abstract
Mitochondrial cytochrome c maturation (CCM) requires heme attachment via distinct pathways termed systems I and III. The mosaic distribution of these systems in Archaeplastida raises questions about the genetic mechanisms and evolutionary forces promoting repeated evolution. Here, we show a recurrent shift from ancestral system I to the eukaryotic-specific holocytochrome c synthase (HCCS) of system III in 11 archaeplastid lineages. Archaeplastid HCCS is sufficient to rescue mutants of yeast system III and Arabidopsis system I. Algal HCCS mutants exhibit impaired growth and respiration, and altered biochemical and metabolic profiles, likely resulting from deficient CCM and reduced cytochrome c-dependent respiratory activity. Our findings demonstrate that archaeplastid HCCS homologs function as system III components in the absence of system I. These results elucidate the evolutionary trajectory and functional divergence of CCM pathways in Archaeplastida, providing insight into the causes, mechanisms, and consequences of repeated cooption of an entire biological pathway.
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Affiliation(s)
- Huang Li
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Soujanya Akella
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Carina Engstler
- Department Biologie I-Botanik, Ludwig-Maximilians-Universität München, D-82152, Planegg-Martinsried, Germany
| | - Joy J Omini
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Moira Rodriguez
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Toshihiro Obata
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Chris Carrie
- School of Biological Sciences, University of Auckland, Auckland, 1142, New Zealand
| | - Heriberto Cerutti
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Jeffrey P Mower
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.
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Dupuis S, Lingappa UF, Mayali X, Sindermann ES, Chastain JL, Weber PK, Stuart R, Merchant SS. Scarcity of fixed carbon transfer in a model microbial phototroph-heterotroph interaction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.26.577492. [PMID: 38328118 PMCID: PMC10849638 DOI: 10.1101/2024.01.26.577492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
While the green alga Chlamydomonas reinhardtii has long served as a reference organism, few studies have interrogated its role as a primary producer in microbial interactions. Here, we quantitatively investigated C. reinhardtii's capacity to support a heterotrophic microbe using the established coculture system with Mesorhizobium japonicum , a vitamin B 12 -producing α- proteobacterium. Using stable isotope probing and nanoscale secondary ion mass spectrometry (nanoSIMS), we tracked the flow of photosynthetic fixed carbon and consequent bacterial biomass synthesis under continuous and diel light with single-cell resolution. We found that more 13 C fixed by the alga was taken up by bacterial cells under continuous light, invalidating the hypothesis that the alga's fermentative degradation of starch reserves during the night would boost M. japonicum heterotrophy. 15 NH 4 assimilation rates and changes in cell size revealed that the carbon transferred was insufficient for balanced growth of M. japonicum cells, which instead underwent reductive division. However, despite this sign of starvation, M. japonicum still supported a B 12 -dependent C. reinhardtii mutant. Finally, we showed that bacterial proliferation could be supported solely by the algal lysis that occurred in coculture, highlighting the role of necromass in carbon cycling. Collectively, these results reveal the scarcity of fixed carbon in this microbial trophic relationship, demonstrate B 12 exchange even during bacterial starvation, and underscore the importance of quantitative approaches for assessing metabolic coupling in algal-bacterial interactions.
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Lv Y, Han F, Liu M, Zhang T, Cui G, Wang J, Yang Y, Yang YG, Yang W. Characteristics of N 6-methyladenosine Modification During Sexual Reproduction of Chlamydomonas reinhardtii. GENOMICS, PROTEOMICS & BIOINFORMATICS 2023; 21:756-768. [PMID: 35550876 PMCID: PMC10787120 DOI: 10.1016/j.gpb.2022.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/12/2022] [Accepted: 04/24/2022] [Indexed: 06/15/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii (hereafter Chlamydomonas) possesses both plant and animal attributes, and it is an ideal model organism for studying fundamental processes such as photosynthesis, sexual reproduction, and life cycle. N6-methyladenosine (m6A) is the most prevalent mRNA modification, and it plays important roles during sexual reproduction in animals and plants. However, the pattern and function of m6A modification during the sexual reproduction of Chlamydomonas remain unknown. Here, we performed transcriptome and methylated RNA immunoprecipitation sequencing (MeRIP-seq) analyses on six samples from different stages during sexual reproduction of the Chlamydomonas life cycle. The results show that m6A modification frequently occurs at the main motif of DRAC (D = G/A/U, R = A/G) in Chlamydomonas mRNAs. Moreover, m6A peaks in Chlamydomonas mRNAs are mainly enriched in the 3' untranslated regions (3'UTRs) and negatively correlated with the abundance of transcripts at each stage. In particular, there is a significant negative correlation between the expression levels and the m6A levels of genes involved in the microtubule-associated pathway, indicating that m6A modification influences the sexual reproduction and the life cycle of Chlamydomonas by regulating microtubule-based movement. In summary, our findings are the first to demonstrate the distribution and the functions of m6A modification in Chlamydomonas mRNAs and provide new evolutionary insights into m6A modification in the process of sexual reproduction in other plant organisms.
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Affiliation(s)
- Ying Lv
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fei Han
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengxia Liu
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing 100101, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ting Zhang
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing 100101, China
| | - Guanshen Cui
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing 100101, China
| | - Jiaojiao Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ying Yang
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing 100101, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China
| | - Yun-Gui Yang
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing 100101, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China
| | - Wenqiang Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China; Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100093, China.
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Liu P, Ye DM, Chen M, Zhang J, Huang XH, Shen LL, Xia KK, Xu XJ, Xu YC, Guo YL, Wang YC, Huang F. Scaling-up and proteomic analysis reveals photosynthetic and metabolic insights toward prolonged H 2 photoproduction in Chlamydomonas hpm91 mutant lacking proton gradient regulation 5 (PGR5). PHOTOSYNTHESIS RESEARCH 2022; 154:397-411. [PMID: 35974136 PMCID: PMC9722884 DOI: 10.1007/s11120-022-00945-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
Clean and sustainable H2 production is crucial to a carbon-neutral world. H2 generation by Chlamydomonas reinhardtii is an attractive approach for solar-H2 from H2O. However, it is currently not large-scalable because of lacking desirable strains with both optimal H2 productivity and sufficient knowledge of underlying molecular mechanism. We hereby carried out extensive and in-depth investigations of H2 photoproduction of hpm91 mutant lacking PGR5 (Proton Gradient Regulation 5) toward its up-scaling and fundamental mechanism issues. We show that hpm91 is at least 100-fold scalable (up to 10 L) with continuous H2 collection of 7287 ml H2/10L-HPBR in averagely 26 days under sulfur deprivation. Also, we show that hpm91 is robust and active during sustained H2 photoproduction, most likely due to decreased intracellular ROS relative to wild type. Moreover, we obtained quantitative proteomic profiles of wild type and hpm91 at four representing time points of H2 evolution, leading to 2229 and 1350 differentially expressed proteins, respectively. Compared to wild type, major proteome alterations of hpm91 include not only core subunits of photosystems and those related to anti-oxidative responses but also essential proteins in photosynthetic antenna, C/N metabolic balance, and sulfur assimilation toward both cysteine biosynthesis and sulfation of metabolites during sulfur-deprived H2 production. These results reveal not only new insights of cellular and molecular basis of enhanced H2 production in hpm91 but also provide additional candidate gene targets and modules for further genetic modifications and/or in artificial photosynthesis mimics toward basic and applied research aiming at advancing solar-H2 technology.
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Affiliation(s)
- Peng Liu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - De-Min Ye
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mei Chen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Jin Zhang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xia-He Huang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Li-Li Shen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ke-Ke Xia
- BGI-Shenzhen, Shenzhen, 518083, China
| | - Xiao-Jing Xu
- BGI-Shenzhen, Shenzhen, 518083, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yong-Chao Xu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ya-Long Guo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Ying-Chun Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Fang Huang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
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Huang G, Zhao D, Lan C, Wu B, Li X, Lou S, Zheng Y, Huang Y, Hu Z, Jia B. Glucose-assisted trophic conversion of Chlamydomonas reinhardtii by expression of glucose transporter GLUT1. ALGAL RES 2022. [DOI: 10.1016/j.algal.2021.102626] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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7
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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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Larrea-Álvarez M, Purton S. The Chloroplast of Chlamydomonas reinhardtii as a Testbed for Engineering Nitrogen Fixation into Plants. Int J Mol Sci 2021; 22:8806. [PMID: 34445505 PMCID: PMC8395883 DOI: 10.3390/ijms22168806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 08/05/2021] [Accepted: 08/10/2021] [Indexed: 12/27/2022] Open
Abstract
Eukaryotic organisms such as plants are unable to utilise nitrogen gas (N2) directly as a source of this essential element and are dependent either on its biological conversion to ammonium by diazotrophic prokaryotes, or its supply as chemically synthesised nitrate fertiliser. The idea of genetically engineering crops with the capacity to fix N2 by introduction of the bacterial nitrogenase enzyme has long been discussed. However, the expression of an active nitrogenase must overcome several major challenges: the coordinated expression of multiple genes to assemble an enzyme complex containing several different metal cluster co-factors; the supply of sufficient ATP and reductant to the enzyme; the enzyme's sensitivity to oxygen; and the intracellular accumulation of ammonium. The chloroplast of plant cells represents an attractive location for nitrogenase expression, but engineering the organelle's genome is not yet feasible in most crop species. However, the unicellular green alga Chlamydomonas reinhardtii represents a simple model for photosynthetic eukaryotes with a genetically tractable chloroplast. In this review, we discuss the main advantages, and limitations, of this microalga as a testbed for producing such a complex multi-subunit enzyme. Furthermore, we suggest that a minimal set of six transgenes are necessary for chloroplast-localised synthesis of an 'Fe-only' nitrogenase, and from this set we demonstrate the stable expression and accumulation of the homocitrate synthase, NifV, under aerobic conditions. Arguably, further studies in C. reinhardtii aimed at testing expression and function of the full gene set would provide the groundwork for a concerted future effort to create nitrogen-fixing crops.
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Affiliation(s)
- Marco Larrea-Álvarez
- School of Biological Sciences and Engineering, Yachay-Tech University Hacienda San José, Urcuquí-Imbabura 100650, Ecuador;
- Algal Research Group, Department of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Saul Purton
- Algal Research Group, Department of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
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Occurrence, Evolution and Specificities of Iron-Sulfur Proteins and Maturation Factors in Chloroplasts from Algae. Int J Mol Sci 2021; 22:ijms22063175. [PMID: 33804694 PMCID: PMC8003979 DOI: 10.3390/ijms22063175] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/25/2021] [Accepted: 03/17/2021] [Indexed: 01/08/2023] Open
Abstract
Iron-containing proteins, including iron-sulfur (Fe-S) proteins, are essential for numerous electron transfer and metabolic reactions. They are present in most subcellular compartments. In plastids, in addition to sustaining the linear and cyclic photosynthetic electron transfer chains, Fe-S proteins participate in carbon, nitrogen, and sulfur assimilation, tetrapyrrole and isoprenoid metabolism, and lipoic acid and thiamine synthesis. The synthesis of Fe-S clusters, their trafficking, and their insertion into chloroplastic proteins necessitate the so-called sulfur mobilization (SUF) protein machinery. In the first part, we describe the molecular mechanisms that allow Fe-S cluster synthesis and insertion into acceptor proteins by the SUF machinery and analyze the occurrence of the SUF components in microalgae, focusing in particular on the green alga Chlamydomonas reinhardtii. In the second part, we describe chloroplastic Fe-S protein-dependent pathways that are specific to Chlamydomonas or for which Chlamydomonas presents specificities compared to terrestrial plants, putting notable emphasis on the contribution of Fe-S proteins to chlorophyll synthesis in the dark and to the fermentative metabolism. The occurrence and evolutionary conservation of these enzymes and pathways have been analyzed in all supergroups of microalgae performing oxygenic photosynthesis.
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Licausi F, Giuntoli B. Synthetic biology of hypoxia. THE NEW PHYTOLOGIST 2021; 229:50-56. [PMID: 31960974 PMCID: PMC7754509 DOI: 10.1111/nph.16441] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 01/03/2020] [Indexed: 05/06/2023]
Abstract
Synthetic biology can greatly aid the investigation of fundamental regulatory mechanisms and enable their direct deployment in the host organisms of choice. In the field of plant hypoxia physiology, a synthetic biology approach has recently been exploited to infer general properties of the plant oxygen sensing mechanism, by expression of plant-specific components in yeast. Moreover, genetic sensors have been devised to report cellular oxygen levels or physiological parameters associated with hypoxia, and orthogonal switches have been introduced in plants to trigger oxygen-specific responses. Upcoming applications are expected, such as genetic tailoring of oxygen-responsive traits, engineering of plant hypoxic metabolism and oxygen delivery to hypoxic tissues, and expansion of the repertoire of genetically encoded oxygen sensors.
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Affiliation(s)
- Francesco Licausi
- Biology DepartmentUniversity of PisaVia L. Ghini 1356126PisaItaly
- Institute of Life SciencesScuola Superiore Sant’AnnaPlantlab, Via Guidiccioni 8/10PisaItaly
| | - Beatrice Giuntoli
- Biology DepartmentUniversity of PisaVia L. Ghini 1356126PisaItaly
- Institute of Life SciencesScuola Superiore Sant’AnnaPlantlab, Via Guidiccioni 8/10PisaItaly
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Hammarlund EU, Flashman E, Mohlin S, Licausi F. Oxygen-sensing mechanisms across eukaryotic kingdoms and their roles in complex multicellularity. Science 2020; 370:370/6515/eaba3512. [PMID: 33093080 DOI: 10.1126/science.aba3512] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 07/07/2020] [Indexed: 12/17/2022]
Abstract
Oxygen-sensing mechanisms of eukaryotic multicellular organisms coordinate hypoxic cellular responses in a spatiotemporal manner. Although this capacity partly allows animals and plants to acutely adapt to oxygen deprivation, its functional and historical roots in hypoxia emphasize a broader evolutionary role. For multicellular life-forms that persist in settings with variable oxygen concentrations, the capacity to perceive and modulate responses in and between cells is pivotal. Animals and higher plants represent the most complex life-forms that ever diversified on Earth, and their oxygen-sensing mechanisms demonstrate convergent evolution from a functional perspective. Exploring oxygen-sensing mechanisms across eukaryotic kingdoms can inform us on biological innovations to harness ever-changing oxygen availability at the dawn of complex life and its utilization for their organismal development.
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Affiliation(s)
- Emma U Hammarlund
- Translational Cancer Research, Department of Laboratory Medicine, Lund University, Scheelevägen 8, 223 81 Lund, Sweden. .,Nordic Center for Earth Evolution, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.,Department of Geology, Lund University, Sölvegatan 12, 223 62 Lund, Sweden
| | - Emily Flashman
- Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Sofie Mohlin
- Translational Cancer Research, Department of Laboratory Medicine, Lund University, Scheelevägen 8, 223 81 Lund, Sweden.,Division of Pediatrics, Department of Clinical Sciences, Lund University, 221 00 Lund, Sweden
| | - Francesco Licausi
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK. .,PlantLab, Institute of Life Sciences, Scuola Superiore, Sant'Anna, 56124 Pisa, Italy.,Department of Biology, University of Pisa, Pisa, Italy
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12
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Petrova EV, Kukarskikh GP, Krendeleva TE, Antal TK. The Mechanisms and Role of Photosynthetic Hydrogen Production by Green Microalgae. Microbiology (Reading) 2020. [DOI: 10.1134/s0026261720030169] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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13
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Halim R, Hill DRA, Hanssen E, Webley PA, Martin GJO. Thermally coupled dark-anoxia incubation: A platform technology to induce auto-fermentation and thus cell-wall thinning in both nitrogen-replete and nitrogen-deplete Nannochloropsis slurries. BIORESOURCE TECHNOLOGY 2019; 290:121769. [PMID: 31323512 DOI: 10.1016/j.biortech.2019.121769] [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: 04/20/2019] [Revised: 07/05/2019] [Accepted: 07/06/2019] [Indexed: 06/10/2023]
Abstract
Nitrogen-deprived Nannochloropsis cells invested their fixed carbon into the accumulation of triacylglycerol and cell wall cellulose (thickness of N-replete cell walls = 27.8 ± 5.8, N-deplete cell walls = 51.0 ± 10.2 nm). In this study, the effect of nitrogen depletion on the ability of the cells to weaken their own cell walls via autolysis was investigated. Autolytic cell wall thinning was achieved in both N-replete and N-deplete biomass by incubating highly concentrated slurries in darkness at 38 °C. The incubation forced cells to anaerobically ferment their intracellular cellulose and resulted in 30-40% reduction in cell wall thickness for both biomass types. This wall depletion weakened the cells and increased the extent of cell rupture by mechanical force (from 42 to 78% for N-replete biomass, from 36 to 62% for N-deplete biomass). Importantly, autolysis did not adversely impact the amino acid content of protein-rich N-replete biomass or the fatty acid content of lipid-rich N-deplete biomass.
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Affiliation(s)
- Ronald Halim
- Algal Processing Group, Department of Chemical Engineering, The University of Melbourne, Victoria 3010, Australia.
| | - David R A Hill
- Algal Processing Group, Department of Chemical Engineering, The University of Melbourne, Victoria 3010, Australia
| | - Eric Hanssen
- Advanced Microscopy Unit, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Paul A Webley
- Algal Processing Group, Department of Chemical Engineering, The University of Melbourne, Victoria 3010, Australia
| | - Gregory J O Martin
- Algal Processing Group, Department of Chemical Engineering, The University of Melbourne, Victoria 3010, Australia
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Day/Night Separation of Oxygenic Energy Metabolism and Nuclear DNA Replication in the Unicellular Red Alga Cyanidioschyzon merolae. mBio 2019; 10:mBio.00833-19. [PMID: 31266864 PMCID: PMC6606799 DOI: 10.1128/mbio.00833-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Eukaryotes acquired chloroplasts through an endosymbiotic event in which a cyanobacterium or a unicellular eukaryotic alga was integrated into a previously nonphotosynthetic eukaryotic cell. Photosynthesis by chloroplasts enabled algae to expand their habitats and led to further evolution of land plants. However, photosynthesis causes greater oxidative stress than mitochondrion-based respiration. In seed plants, cell division is restricted to nonphotosynthetic meristematic tissues and populations of photosynthetic cells expand without cell division. Thus, seemingly, photosynthesis is spatially sequestrated from cell proliferation. In contrast, eukaryotic algae possess photosynthetic chloroplasts throughout their life cycle. Here we show that oxygenic energy conversion (daytime) and nuclear DNA replication (night time) are temporally sequestrated in C. merolae. This sequestration enables “safe” proliferation of cells and allows coexistence of chloroplasts and the eukaryotic host cell, as shown in yeast, where mitochondrial respiration and nuclear DNA replication are temporally sequestrated to reduce the mutation rate. The transition from G1 to S phase and subsequent nuclear DNA replication in the cells of many species of eukaryotic algae occur predominantly during the evening and night in the absence of photosynthesis; however, little is known about how day/night changes in energy metabolism and cell cycle progression are coordinated and about the advantage conferred by the restriction of S phase to the night. Using a synchronous culture of the unicellular red alga Cyanidioschyzon merolae, we found that the levels of photosynthetic and respiratory activities peak during the morning and then decrease toward the evening and night, whereas the pathways for anaerobic consumption of pyruvate, produced by glycolysis, are upregulated during the evening and night as reported recently in the green alga Chlamydomonas reinhardtii. Inhibition of photosynthesis by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) largely reduced respiratory activity and the amplitude of the day/night rhythm of respiration, suggesting that the respiratory rhythm depends largely on photosynthetic activity. Even when the timing of G1/S-phase transition was uncoupled from the day/night rhythm by depletion of retinoblastoma-related (RBR) protein, the same patterns of photosynthesis and respiration were observed, suggesting that cell cycle progression and energy metabolism are regulated independently. Progression of the S phase under conditions of photosynthesis elevated the frequency of nuclear DNA double-strand breaks (DSB). These results suggest that the temporal separation of oxygenic energy metabolism, which causes oxidative stress, from nuclear DNA replication reduces the risk of DSB during cell proliferation in C. merolae.
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15
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Kennedy F, Martin A, Bowman JP, Wilson R, McMinn A. Dark metabolism: a molecular insight into how the Antarctic sea-ice diatom Fragilariopsis cylindrus survives long-term darkness. THE NEW PHYTOLOGIST 2019; 223:675-691. [PMID: 30985935 PMCID: PMC6617727 DOI: 10.1111/nph.15843] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 04/02/2019] [Indexed: 05/27/2023]
Abstract
Light underneath Antarctic sea-ice is below detectable limits for up to 4 months of the year. The ability of Antarctic sea-ice diatoms to survive this prolonged darkness relies on their metabolic capability. This study is the first to examine the proteome of a prominent sea-ice diatom in response to extended darkness, focusing on the protein-level mechanisms of dark survival. The Antarctic diatom Fragilariopsis cylindrus was grown under continuous light or darkness for 120 d. The whole cell proteome was quantitatively analysed by nano-LC-MS/MS to investigate metabolic changes that occur during sustained darkness and during recovery under illumination. Enzymes of metabolic pathways, particularly those involved in respiratory processes, tricarboxylic acid cycle, glycolysis, the Entner-Doudoroff pathway, the urea cycle and the mitochondrial electron transport chain became more abundant in the dark. Within the plastid, carbon fixation halted while the upper sections of the glycolysis, gluconeogenesis and pentose phosphate pathways became less active. We have discovered how F. cylindrus utilises an ancient alternative metabolic mechanism that enables its capacity for long-term dark survival. By sustaining essential metabolic processes in the dark, F. cylindrus retains the functionality of the photosynthetic apparatus, ensuring rapid recovery upon re-illumination.
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Affiliation(s)
- Fraser Kennedy
- Institute for Marine and Antarctic StudiesUniversity of TasmaniaHobart7000TasmaniaAustralia
| | - Andrew Martin
- Institute for Marine and Antarctic StudiesUniversity of TasmaniaHobart7000TasmaniaAustralia
| | - John P. Bowman
- Centre for Food Safety and InnovationTasmanian Institute of AgricultureHobart7000TasmaniaAustralia
| | - Richard Wilson
- Central Science LaboratoryUniversity of TasmaniaHobart7000TasmaniaAustralia
| | - Andrew McMinn
- Institute for Marine and Antarctic StudiesUniversity of TasmaniaHobart7000TasmaniaAustralia
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16
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Durante L, Hübner W, Lauersen KJ, Remacle C. Characterization of the GPR1/FUN34/YaaH protein family in the green microalga Chlamydomonas suggests their role as intracellular membrane acetate channels. PLANT DIRECT 2019; 3:e00148. [PMID: 31245784 PMCID: PMC6556978 DOI: 10.1002/pld3.148] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/15/2019] [Accepted: 05/16/2019] [Indexed: 05/17/2023]
Abstract
The unicellular green microalga Chlamydomonas reinhardtii is a powerful photosynthetic model organism which is capable of heterotrophic growth on acetate as a sole carbon source. This capacity has enabled its use for investigations of perturbations in photosynthetic machinery as mutants can be recovered heterotrophically. Fixation of acetate into cellular carbon metabolism occurs first by its conversion into acetyl-CoA by a respective synthase and the generation of succinate by the glyoxylate cycle. These metabolic steps have been recently determined to largely occur in the peroxisomes of this alga; however, little is known about the trafficking and import of acetate or its subcellular compartmentalization. Recently, the genes of five proteins belonging to the GPR1/FUN34/YaaH (GFY) superfamily were observed to exhibit increased expression in C. reinhardtii upon acetate addition, however, no further characterization has been reported. Here, we provide several lines of evidence to implicate Cr GFY1-5 as channels which share structural homology with bacterial succinate-acetate channels and specifically localize to microbodies, which are surprisingly distinct from the glyoxylate cycle-containing peroxisomes. We demonstrate structural models, gene expression profiling, and in vivo fluorescence localization of all five isoforms in the algal cell to further support this role.
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Affiliation(s)
- Lorenzo Durante
- Genetics and Physiology of MicroalgaeInBios/PhytosystemsUniversity of LiegeLiegeBelgium
| | - Wolfgang Hübner
- Biomolecular PhotonicsDepartment of PhysicsBielefeld UniversityBielefeldGermany
| | - Kyle J. Lauersen
- Faculty of BiologyCenter for Biotechnology (CeBiTec)Bielefeld UniversityBielefeldGermany
| | - Claire Remacle
- Genetics and Physiology of MicroalgaeInBios/PhytosystemsUniversity of LiegeLiegeBelgium
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17
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Paik SM, Kim J, Jin E, Jeon NL. Overproduction of recombinant E. coli malate synthase enhances Chlamydomonas reinhardtii biomass by upregulating heterotrophic metabolism. BIORESOURCE TECHNOLOGY 2019; 272:594-598. [PMID: 30348480 DOI: 10.1016/j.biortech.2018.10.029] [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: 09/01/2018] [Revised: 10/10/2018] [Accepted: 10/11/2018] [Indexed: 06/08/2023]
Abstract
High uptake of malate and efficient distribution of intracellular malate to organelles contributed to biomass increase, reducing maintenance energy. In this study, transgenic Chlamydomonas reinhardtii was developed that stably expresses malate synthase in the chloroplast. The strains under glyoxylate treatment showed 19% more increase in microalgal biomass than wild-type. By RNA analysis, transcript levels of malate dehydrogenase (MDH4) and acetyl-CoA synthetase (ACS3), isocitrate lyase (ICL1) and malate synthase (MAS1), were significantly more expressed (17%, 42%, 24%, and 18% respectively), which was consistent with reported heterotrophic metabolism flux analysis with the objective function maximizing biomass. Photosynthetic Fv/Fm was slightly reduced. A more meticulous analysis is necessary, but, in the transgenic microalgae with malate synthase overexpression, the metabolism is likely to more rely on heterotrophic energy production via TCA cycle and glyoxylate shunt than on photosynthesis, resulting in the increase in microalgal biomass.
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Affiliation(s)
- Sang-Min Paik
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Joonwon Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - EonSeon Jin
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea.
| | - Noo Li Jeon
- Interdisciplinary Program for Bioengineering, Seoul National University, Seoul 08826, Republic of Korea; School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, Republic of Korea; Institute of Advanced Mechanics and Design, Seoul National University, Seoul 08826, Republic of Korea.
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18
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Sasso S, Stibor H, Mittag M, Grossman AR. From molecular manipulation of domesticated Chlamydomonas reinhardtii to survival in nature. eLife 2018; 7:39233. [PMID: 30382941 PMCID: PMC6211829 DOI: 10.7554/elife.39233] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 10/12/2018] [Indexed: 01/19/2023] Open
Abstract
In the mid-20th century, the unicellular and genetically tractable green alga Chlamydomonas reinhardtii was first developed as a model organism to elucidate fundamental cellular processes such as photosynthesis, light perception and the structure, function and biogenesis of cilia. Various studies of C. reinhardtii have profoundly advanced plant and cell biology, and have also impacted algal biotechnology and our understanding of human disease. However, the 'real' life of C. reinhardtii in the natural environment has largely been neglected. To extend our understanding of the biology of C. reinhardtii, it will be rewarding to explore its behavior in its natural habitats, learning more about its abundance and life cycle, its genetic and physiological diversity, and its biotic and abiotic interactions.
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Affiliation(s)
- Severin Sasso
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Herwig Stibor
- Department Biology II, Ludwig Maximilian University, Munich, Germany
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
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19
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Smith RT, Gilmour DJ. The influence of exogenous organic carbon assimilation and photoperiod on the carbon and lipid metabolism of Chlamydomonas reinhardtii. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.01.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Vargas SR, Santos PVD, Giraldi LA, Zaiat M, Calijuri MDC. Anaerobic phototrophic processes of hydrogen production by different strains of microalgae Chlamydomonas sp. FEMS Microbiol Lett 2018; 365:4953416. [DOI: 10.1093/femsle/fny073] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 03/23/2018] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sarah Regina Vargas
- Department of Hydraulic and Sanitation, Universidade de São Paulo Escola de Engenharia de São Carlos, Av. Trabalhador São-carlense, 400, Arnold Schimidt, São Carlos 13566-590, Brazil
| | - Paulo Vagner dos Santos
- Department of Hydraulic and Sanitation, Universidade de São Paulo Escola de Engenharia de São Carlos, Av. Trabalhador São-carlense, 400, Arnold Schimidt, São Carlos 13566-590, Brazil
| | - Laís Albuquerque Giraldi
- Department of Hydraulic and Sanitation, Universidade de São Paulo Escola de Engenharia de São Carlos, Av. Trabalhador São-carlense, 400, Arnold Schimidt, São Carlos 13566-590, Brazil
| | - Marcelo Zaiat
- Department of Hydraulic and Sanitation, Universidade de São Paulo Escola de Engenharia de São Carlos, Av. João Dagnone, 1100, Santa Angelina, São Carlos-SP, 13563-120, Brazil
| | - Maria do Carmo Calijuri
- Department of Hydraulic and Sanitation, Universidade de São Paulo Escola de Engenharia de São Carlos, Av. Trabalhador São-carlense, 400, Arnold Schimidt, São Carlos 13566-590, Brazil
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Burns JA, Zhang H, Hill E, Kim E, Kerney R. Transcriptome analysis illuminates the nature of the intracellular interaction in a vertebrate-algal symbiosis. eLife 2017; 6:e22054. [PMID: 28462779 PMCID: PMC5413350 DOI: 10.7554/elife.22054] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 03/15/2017] [Indexed: 12/19/2022] Open
Abstract
During embryonic development, cells of the green alga Oophila amblystomatis enter cells of the salamander Ambystoma maculatum forming an endosymbiosis. Here, using de novo dual-RNA seq, we compared the host salamander cells that harbored intracellular algae to those without algae and the algae inside the animal cells to those in the egg capsule. This two-by-two-way analysis revealed that intracellular algae exhibit hallmarks of cellular stress and undergo a striking metabolic shift from oxidative metabolism to fermentation. Culturing experiments with the alga showed that host glutamine may be utilized by the algal endosymbiont as a primary nitrogen source. Transcriptional changes in salamander cells suggest an innate immune response to the alga, with potential attenuation of NF-κB, and metabolic alterations indicative of modulation of insulin sensitivity. In stark contrast to its algal endosymbiont, the salamander cells did not exhibit major stress responses, suggesting that the host cell experience is neutral or beneficial.
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Affiliation(s)
- John A Burns
- Division of Invertebrate Zoology, American Museum of Natural History, New York, United States
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, United States
| | - Huanjia Zhang
- Department of Biology, Gettysburg College, Gettysburg, United States
| | - Elizabeth Hill
- Department of Biology, Gettysburg College, Gettysburg, United States
| | - Eunsoo Kim
- Division of Invertebrate Zoology, American Museum of Natural History, New York, United States
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, United States
| | - Ryan Kerney
- Department of Biology, Gettysburg College, Gettysburg, United States
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22
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Lauersen KJ, Willamme R, Coosemans N, Joris M, Kruse O, Remacle C. Peroxisomal microbodies are at the crossroads of acetate assimilation in the green microalga Chlamydomonas reinhardtii. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.03.026] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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23
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Critical role of Chlamydomonas reinhardtii ferredoxin-5 in maintaining membrane structure and dark metabolism. Proc Natl Acad Sci U S A 2015; 112:14978-83. [PMID: 26627249 DOI: 10.1073/pnas.1515240112] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Photosynthetic microorganisms typically have multiple isoforms of the electron transfer protein ferredoxin, although we know little about their exact functions. Surprisingly, a Chlamydomonas reinhardtii mutant null for the ferredoxin-5 gene (FDX5) completely ceased growth in the dark, with both photosynthetic and respiratory functions severely compromised; growth in the light was unaffected. Thylakoid membranes in dark-maintained fdx5 mutant cells became severely disorganized concomitant with a marked decrease in the ratio of monogalactosyldiacylglycerol to digalactosyldiacylglycerol, major lipids in photosynthetic membranes, and the accumulation of triacylglycerol. Furthermore, FDX5 was shown to physically interact with the fatty acid desaturases CrΔ4FAD and CrFAD6, likely donating electrons for the desaturation of fatty acids that stabilize monogalactosyldiacylglycerol. Our results suggest that in photosynthetic organisms, specific redox reactions sustain dark metabolism, with little impact on daytime growth, likely reflecting the tailoring of electron carriers to unique intracellular metabolic circuits under these two very distinct redox conditions.
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Antal TK, Krendeleva TE, Tyystjärvi E. Multiple regulatory mechanisms in the chloroplast of green algae: relation to hydrogen production. PHOTOSYNTHESIS RESEARCH 2015; 125:357-81. [PMID: 25986411 DOI: 10.1007/s11120-015-0157-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 05/11/2015] [Indexed: 05/10/2023]
Abstract
A complex regulatory network in the chloroplast of green algae provides an efficient tool for maintenance of energy and redox balance in the cell under aerobic and anaerobic conditions. In this review, we discuss the structural and functional organizations of electron transport pathways in the chloroplast, and regulation of photosynthesis in the green microalga Chlamydomonas reinhardtii. The focus is on the regulatory mechanisms induced in response to nutrient deficiency stress and anoxia and especially on the role of a hydrogenase-mediated reaction in adaptation to highly reducing conditions and ATP deficiency in the cell.
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Affiliation(s)
- Taras K Antal
- Faculty of Biology, Moscow State University, Vorobyevi Gory, Moscow, 119992, Russia,
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25
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Benning C. Fueling research on Chlamydomonas. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:363-364. [PMID: 25906814 DOI: 10.1111/tpj.12831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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