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Shin SE, Koh HG, Park K, Park SH, Chang YK, Kang NK. Increasing lipid production in Chlamydomonas reinhardtii through genetic introduction for the overexpression of glyceraldehyde-3-phosphate dehydrogenase. Front Bioeng Biotechnol 2024; 12:1396127. [PMID: 38707501 PMCID: PMC11066295 DOI: 10.3389/fbioe.2024.1396127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 04/05/2024] [Indexed: 05/07/2024] Open
Abstract
Microalgae, valued for their sustainability and CO2 fixation capabilities, are emerging as promising sources of biofuels and high-value compounds. This study aimed to boost lipid production in C. reinhardtii by overexpressing chloroplast glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a key enzyme in the Calvin cycle and glycolysis, under the control of a nitrogen-inducible NIT1 promoter, to positively impact overall carbon metabolism. The standout transformant, PNG#7, exhibited significantly increased lipid production under nitrogen starvation, with biomass rising by 44% and 76% on days 4 and 16, respectively. Fatty acid methyl ester (FAME) content in PNG#7 surged by 2.4-fold and 2.1-fold, notably surpassing the wild type (WT) in lipid productivity by 3.4 and 3.7 times on days 4 and 16, respectively. Transcriptome analysis revealed a tenfold increase in transgenic GAPDH expression and significant upregulation of genes involved in fatty acid and triacylglycerol synthesis, especially the gene encoding acyl-carrier protein gene (ACP, Cre13. g577100. t1.2). In contrast, genes related to cellulose synthesis were downregulated. Single Nucleotide Polymorphism (SNP)/Indel analysis indicated substantial DNA modifications, which likely contributed to the observed extensive transcriptomic and phenotypic changes. These findings suggest that overexpressing chloroplast GAPDH, coupled with genetic modifications, effectively enhances lipid synthesis in C. reinhardtii. This study not only underscores the potential of chloroplast GAPDH overexpression in microalgal lipid synthesis but also highlights the expansive potential of metabolic engineering in microalgae for biofuel production.
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Affiliation(s)
- Sung-Eun Shin
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Hyun Gi Koh
- Department of Biological and Chemical Engineering, Hongik University, Sejong, Republic of Korea
| | - Kyungmoon Park
- Department of Biological and Chemical Engineering, Hongik University, Sejong, Republic of Korea
| | - See-Hyoung Park
- Department of Biological and Chemical Engineering, Hongik University, Sejong, Republic of Korea
| | - Yong Keun Chang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Nam Kyu Kang
- Department of Chemical Engineering, College of Engineering, Kyung Hee University, Yongin, Republic of Korea
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Terentyev VV, Shukshina AK. CAH3 from Chlamydomonas reinhardtii: Unique Carbonic Anhydrase of the Thylakoid Lumen. Cells 2024; 13:109. [PMID: 38247801 PMCID: PMC10814762 DOI: 10.3390/cells13020109] [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: 11/23/2023] [Revised: 12/29/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
CAH3 is the only carbonic anhydrase (CA) present in the thylakoid lumen of the green algae Chlamydomonas reinhardtii. The monomer of the enzyme has a molecular weight of ~29.5 kDa with high CA activity. Through its dehydration activity, CAH3 can be involved either in the carbon-concentrating mechanism supplying CO2 for RuBisCO in the pyrenoid or in supporting the maximal photosynthetic activity of photosystem II (PSII) by accelerating the removal of protons from the active center of the water-oxidizing complex. Both proposed roles are considered in this review, together with a description of the enzymatic parameters of native and recombinant CAH3, the crystal structure of the protein, and the possible use of lumenal CA as a tool for increasing biomass production in higher plants. The identified involvement of lumenal CAH3 in the function of PSII is still unique among green algae and higher plants and can be used to understand the mechanism(s) of the functional interconnection between PSII and the proposed CA(s) of the thylakoid lumen in other organisms.
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Affiliation(s)
- Vasily V. Terentyev
- Institute of Basic Biological Problems, FRC PSCBR RAS, 142290 Pushchino, Russia
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3
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He S, Crans VL, Jonikas MC. The pyrenoid: the eukaryotic CO2-concentrating organelle. THE PLANT CELL 2023; 35:3236-3259. [PMID: 37279536 PMCID: PMC10473226 DOI: 10.1093/plcell/koad157] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/09/2023] [Accepted: 05/17/2023] [Indexed: 06/08/2023]
Abstract
The pyrenoid is a phase-separated organelle that enhances photosynthetic carbon assimilation in most eukaryotic algae and the land plant hornwort lineage. Pyrenoids mediate approximately one-third of global CO2 fixation, and engineering a pyrenoid into C3 crops is predicted to boost CO2 uptake and increase yields. Pyrenoids enhance the activity of the CO2-fixing enzyme Rubisco by supplying it with concentrated CO2. All pyrenoids have a dense matrix of Rubisco associated with photosynthetic thylakoid membranes that are thought to supply concentrated CO2. Many pyrenoids are also surrounded by polysaccharide structures that may slow CO2 leakage. Phylogenetic analysis and pyrenoid morphological diversity support a convergent evolutionary origin for pyrenoids. Most of the molecular understanding of pyrenoids comes from the model green alga Chlamydomonas (Chlamydomonas reinhardtii). The Chlamydomonas pyrenoid exhibits multiple liquid-like behaviors, including internal mixing, division by fission, and dissolution and condensation in response to environmental cues and during the cell cycle. Pyrenoid assembly and function are induced by CO2 availability and light, and although transcriptional regulators have been identified, posttranslational regulation remains to be characterized. Here, we summarize the current knowledge of pyrenoid function, structure, components, and dynamic regulation in Chlamydomonas and extrapolate to pyrenoids in other species.
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Affiliation(s)
- Shan He
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
- Howard Hughes Medical Institute, Princeton University, Princeton, NJ 08540, USA
| | - Victoria L Crans
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
| | - Martin C Jonikas
- Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA
- Howard Hughes Medical Institute, Princeton University, Princeton, NJ 08540, USA
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An Y, Wang D, Du J, Wang X, Xiao J. Pyrenoid: Organelle with efficient CO 2-Concentrating mechanism in algae. JOURNAL OF PLANT PHYSIOLOGY 2023; 287:154044. [PMID: 37392525 DOI: 10.1016/j.jplph.2023.154044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/05/2023] [Accepted: 06/18/2023] [Indexed: 07/03/2023]
Abstract
The carbon dioxide emitted by human accounts for only a small fraction of global photosynthesis consumption, half of which is due to microalgae. The high efficiency of algae photosynthesis is attributed to the pyrenoid-based CO2-concentrating mechanism (CCM). The formation of pyrenoid which has a variety of Rubisco-binding proteins mainly depends on liquid-liquid phase separation (LLPS) of Rubisco, a CO2 fixing enzyme. At present, our understanding of pyrenoid at the molecular level mainly stems from studies of the model algae Chlamydomonas reinhardtii. In this article, we summarize the current research on the structure, assembly and application of Chlamydomonas reinhardtii pyrenoids, providing new ideas for improving crop photosynthetic performance and yield.
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Affiliation(s)
- Yaqi An
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
| | - Dong Wang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
| | - Jingxia Du
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
| | - Xinwei Wang
- College of Agriculture and Forestry, Hebei North University, Zhangjiakou, China.
| | - Jianwei Xiao
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China; Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
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5
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Kasili RW, Rai AK, Moroney JV. LCIB functions as a carbonic anhydrase: evidence from yeast and Arabidopsis carbonic anhydrase knockout mutants. PHOTOSYNTHESIS RESEARCH 2023; 156:193-204. [PMID: 36856938 DOI: 10.1007/s11120-023-01005-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 02/10/2023] [Indexed: 05/03/2023]
Abstract
Chlamydomonas reinhardtii evolved a CO2-concentrating mechanism (CCM) because of the limited CO2 in its natural environment. One critical component of the C. reinhardtii CCM is the limiting CO2 inducible B (LCIB) protein. LCIB is required for acclimation to air levels of CO2. C. reinhardtii cells with a mutated LCIB protein have an 'air-dier' phenotype when grown in low CO2 conditions, meaning they die in air levels of CO2 but can grow in high and very low CO2 conditions. The LCIB protein functions together with its close homolog in C. reinhardtii, limiting CO2 inducible C protein (LCIC), in a hexameric LCIB-LCIC complex. LCIB has been proposed to act as a vectoral carbonic anhydrase (CA) that helps to recapture CO2 that would otherwise leak out of the chloroplast. Although both LCIB and LCIC are structurally similar to βCAs, their CA activity has not been demonstrated to date. We provide evidence that LCIB is an active CA using a Saccharomyces cerevisiae CA knockout mutant (∆NCE103) and an Arabidopsis thaliana βCA5 knockout mutant (βca5). We show that different truncated versions of the LCIB protein complement ∆NCE103, while the full length LCIB protein complements βca5 plants, so that both the yeast and plant mutants can grow in low CO2 conditions.
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Affiliation(s)
- Remmy W Kasili
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Ashwani K Rai
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - James V Moroney
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA.
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Nawaly H, Tanaka A, Toyoshima Y, Tsuji Y, Matsuda Y. Localization and characterization θ carbonic anhydrases in Thalassiosira pseudonana. PHOTOSYNTHESIS RESEARCH 2023; 156:217-229. [PMID: 36862281 DOI: 10.1007/s11120-023-01007-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 02/12/2023] [Indexed: 05/03/2023]
Abstract
Carbonic anhydrase (CA) is a crucial component for the operation of CO2-concentrating mechanisms (CCMs) in the majority of aquatic photoautotrophs that maintain the global primary production. In the genome of the centric marine diatom, Thalassiosira pseudonana, there are four putative gene sequences that encode θ-type CA, which was a type of CA recently identified in marine diatoms and green algae. In the present study, specific subcellular locations of four θCAs, TpθCA1, TpθCA2, TpθCA3, and TpθCA4 were determined by expressing GFP-fused proteins of these TpθCAs in T. pseudonana. As a result, C-terminal GFP fusion proteins of TpθCA1, TpθCA2, and TpθCA3 were all localized in the chloroplast; TpθCA2 was at the central chloroplast area, and the other two TpθCAs were throughout the chloroplast. Immunogold-labeling transmission electron microscopy was further performed for the transformants expressing TpθCA1:GFP and TpθCA2:GFP with anti-GFP-monoclonal antibody. TpθCA1:GFP was localized in the free stroma area, including the peripheral pyrenoid area. TpθCA2:GFP was clearly located as a lined distribution at the central part of the pyrenoid structure, which was most likely the pyrenoid-penetrating thylakoid. Considering the presence of the sequence encoding the N-terminal thylakoid-targeting domain in the TpθCA2 gene, this localization was likely the lumen of the pyrenoid-penetrating thylakoid. On the other hand, TpθCA4:GFP was localized in the cytoplasm. Transcript analysis of these TpθCAs revealed that TpθCA2 and TpθCA3 were upregulated in atmospheric CO2 (0.04% CO2, LC) levels, while TpθCA1 and TpθCA4 were highly induced under 1% CO2 (HC) condition. The genome-editing knockout (KO) of TpθCA1, by CRISPR/Cas9 nickase, gave a silent phenotype in T. pseudonana under LC-HC conditions, which was in sharp agreement with the case of the previously reported TpθCA3 KO. In sharp contrast, TpθCA2 KO is so far unsuccessful, suggesting a housekeeping role of TpθCA2. The silent phenotype of KO strains of stromal CAs suggests that TpαCA1, TpθCA1, and TpθCA3 may have functional redundancy, but different transcript regulations in response to CO2 of these stromal CAs suggest in part their independent roles.
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Affiliation(s)
- Hermanus Nawaly
- Department of Bioscience, School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Atsuko Tanaka
- Department of Chemistry, Biology and Marine Science, Faculty of Science, University of the Ryukyus, Nishihara, 903-0213, Japan
| | - Yui Toyoshima
- Department of Bioscience, School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Yoshinori Tsuji
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan
| | - Yusuke Matsuda
- Department of Bioscience, School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan.
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Adler L, Díaz-Ramos A, Mao Y, Pukacz KR, Fei C, McCormick AJ. New horizons for building pyrenoid-based CO2-concentrating mechanisms in plants to improve yields. PLANT PHYSIOLOGY 2022; 190:1609-1627. [PMID: 35961043 PMCID: PMC9614477 DOI: 10.1093/plphys/kiac373] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 07/06/2022] [Indexed: 05/06/2023]
Abstract
Many photosynthetic species have evolved CO2-concentrating mechanisms (CCMs) to improve the efficiency of CO2 assimilation by Rubisco and reduce the negative impacts of photorespiration. However, the majority of plants (i.e. C3 plants) lack an active CCM. Thus, engineering a functional heterologous CCM into important C3 crops, such as rice (Oryza sativa) and wheat (Triticum aestivum), has become a key strategic ambition to enhance yield potential. Here, we review recent advances in our understanding of the pyrenoid-based CCM in the model green alga Chlamydomonas reinhardtii and engineering progress in C3 plants. We also discuss recent modeling work that has provided insights into the potential advantages of Rubisco condensation within the pyrenoid and the energetic costs of the Chlamydomonas CCM, which, together, will help to better guide future engineering approaches. Key findings include the potential benefits of Rubisco condensation for carboxylation efficiency and the need for a diffusional barrier around the pyrenoid matrix. We discuss a minimal set of components for the CCM to function and that active bicarbonate import into the chloroplast stroma may not be necessary for a functional pyrenoid-based CCM in planta. Thus, the roadmap for building a pyrenoid-based CCM into plant chloroplasts to enhance the efficiency of photosynthesis now appears clearer with new challenges and opportunities.
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Affiliation(s)
| | | | - Yuwei Mao
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Krzysztof Robin Pukacz
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Chenyi Fei
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA
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8
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Systematic characterization of gene function in the photosynthetic alga Chlamydomonas reinhardtii. Nat Genet 2022; 54:705-714. [PMID: 35513725 PMCID: PMC9110296 DOI: 10.1038/s41588-022-01052-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 03/15/2022] [Indexed: 12/12/2022]
Abstract
Most genes in photosynthetic organisms remain functionally uncharacterized. Here, using a barcoded mutant library of the model eukaryotic alga Chlamydomonas reinhardtii, we determined the phenotypes of more than 58,000 mutants under more than 121 different environmental growth conditions and chemical treatments. A total of 59% of genes are represented by at least one mutant that showed a phenotype, providing clues to the functions of thousands of genes. Mutant phenotypic profiles place uncharacterized genes into functional pathways such as DNA repair, photosynthesis, the CO2-concentrating mechanism and ciliogenesis. We illustrate the value of this resource by validating phenotypes and gene functions, including three new components of an actin cytoskeleton defense pathway. The data also inform phenotype discovery in land plants; mutants in Arabidopsis thaliana genes exhibit phenotypes similar to those we observed in their Chlamydomonas homologs. We anticipate that this resource will guide the functional characterization of genes across the tree of life. Systematic phenotyping of 58,101 mutants of the model eukaryotic alga Chlamydomonas reinhardtii under 121 environmental and chemical stress conditions provides a large resource for characterizing gene function.
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Fei C, Wilson AT, Mangan NM, Wingreen NS, Jonikas MC. Modelling the pyrenoid-based CO 2-concentrating mechanism provides insights into its operating principles and a roadmap for its engineering into crops. NATURE PLANTS 2022; 8:583-595. [PMID: 35596080 PMCID: PMC9122830 DOI: 10.1038/s41477-022-01153-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 04/11/2022] [Indexed: 05/19/2023]
Abstract
Many eukaryotic photosynthetic organisms enhance their carbon uptake by supplying concentrated CO2 to the CO2-fixing enzyme Rubisco in an organelle called the pyrenoid. Ongoing efforts seek to engineer this pyrenoid-based CO2-concentrating mechanism (PCCM) into crops to increase yields. Here we develop a computational model for a PCCM on the basis of the postulated mechanism in the green alga Chlamydomonas reinhardtii. Our model recapitulates all Chlamydomonas PCCM-deficient mutant phenotypes and yields general biophysical principles underlying the PCCM. We show that an effective and energetically efficient PCCM requires a physical barrier to reduce pyrenoid CO2 leakage, as well as proper enzyme localization to reduce futile cycling between CO2 and HCO3-. Importantly, our model demonstrates the feasibility of a purely passive CO2 uptake strategy at air-level CO2, while active HCO3- uptake proves advantageous at lower CO2 levels. We propose a four-step engineering path to increase the rate of CO2 fixation in the plant chloroplast up to threefold at a theoretical cost of only 1.3 ATP per CO2 fixed, thereby offering a framework to guide the engineering of a PCCM into land plants.
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Affiliation(s)
- Chenyi Fei
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Alexandra T Wilson
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Niall M Mangan
- Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, IL, USA.
| | - Ned S Wingreen
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
| | - Martin C Jonikas
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
- Howard Hughes Medical Institute, Princeton University, Princeton, NJ, USA.
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Yamano T, Toyokawa C, Shimamura D, Matsuoka T, Fukuzawa H. CO2-dependent migration and relocation of LCIB, a pyrenoid-peripheral protein in Chlamydomonas reinhardtii. PLANT PHYSIOLOGY 2022; 188:1081-1094. [PMID: 34791500 PMCID: PMC8825250 DOI: 10.1093/plphys/kiab528] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/15/2021] [Indexed: 05/18/2023]
Abstract
Most microalgae overcome the difficulty of acquiring inorganic carbon (Ci) in aquatic environments by inducing a CO2-concentrating mechanism (CCM). In the green alga Chlamydomonas reinhardtii, two distinct photosynthetic acclimation states have been described under CO2-limiting conditions (low-CO2 [LC] and very low-CO2 [VLC]). LC-inducible protein B (LCIB), structurally characterized as carbonic anhydrase, localizes in the chloroplast stroma under CO2-supplied and LC conditions. In VLC conditions, it migrates to aggregate around the pyrenoid, where the CO2-fixing enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase is enriched. Although the physiological importance of LCIB localization changes in the chloroplast has been shown, factors necessary for the localization changes remain uncertain. Here, we examined the effect of pH, light availability, photosynthetic electron flow, and protein synthesis on the localization changes, along with measuring Ci concentrations. LCIB dispersed or localized in the basal region of the chloroplast stroma at 8.3-15 µM CO2, whereas LCIB migrated toward the pyrenoid at 6.5 µM CO2. Furthermore, LCIB relocated toward the pyrenoid at 2.6-3.4 µM CO2, even in cells in the dark or treated with 3-(3,4-dichlorophenyl)-1,1-dimethylurea and cycloheximide in light. In contrast, in the mutant lacking CCM1, a master regulator of CCM, LCIB remained dispersed even at 4.3 µM CO2. Meanwhile, a simultaneous expression of LCIC, an interacting protein of LCIB, induced the localization of several speckled structures at the pyrenoid periphery. These results suggest that the localization changes of LCIB require LCIC and are controlled by CO2 concentration with ∼7 µM as the boundary.
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Affiliation(s)
- Takashi Yamano
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
- Author for communication:
| | - Chihana Toyokawa
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Daisuke Shimamura
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Toshiki Matsuoka
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Hideya Fukuzawa
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
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11
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Choi HI, Hwang SW, Kim J, Park B, Jin E, Choi IG, Sim SJ. Augmented CO 2 tolerance by expressing a single H +-pump enables microalgal valorization of industrial flue gas. Nat Commun 2021; 12:6049. [PMID: 34663809 PMCID: PMC8523702 DOI: 10.1038/s41467-021-26325-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 10/01/2021] [Indexed: 12/02/2022] Open
Abstract
Microalgae can accumulate various carbon-neutral products, but their real-world applications are hindered by their CO2 susceptibility. Herein, the transcriptomic changes in a model microalga, Chlamydomonas reinhardtii, in a high-CO2 milieu (20%) are evaluated. The primary toxicity mechanism consists of aberrantly low expression of plasma membrane H+-ATPases (PMAs) accompanied by intracellular acidification. Our results demonstrate that the expression of a universally expressible PMA in wild-type strains makes them capable of not only thriving in acidity levels that they usually cannot survive but also exhibiting 3.2-fold increased photoautotrophic production against high CO2 via maintenance of a higher cytoplasmic pH. A proof-of-concept experiment involving cultivation with toxic flue gas (13 vol% CO2, 20 ppm NOX, and 32 ppm SOX) shows that the production of CO2-based bioproducts by the strain is doubled compared with that by the wild-type, implying that this strategy potentially enables the microalgal valorization of CO2 in industrial exhaust.
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Affiliation(s)
- Hong Il Choi
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Sung-Won Hwang
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Jongrae Kim
- Department of Life Science, Hanyang University, 206, Wangsimni-ro, Seongbuk-gu, Seoul, 04763, Republic of Korea
| | - Byeonghyeok Park
- Department of Biotechnology, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - EonSeon Jin
- Department of Life Science, Hanyang University, 206, Wangsimni-ro, Seongbuk-gu, Seoul, 04763, Republic of Korea
| | - In-Geol Choi
- Department of Biotechnology, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
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Kareya MS, Mariam I, Shaikh KM, Nesamma AA, Jutur PP. Photosynthetic Carbon Partitioning and Metabolic Regulation in Response to Very-Low and High CO 2 in Microchloropsis gaditana NIES 2587. FRONTIERS IN PLANT SCIENCE 2020; 11:981. [PMID: 32719702 PMCID: PMC7348049 DOI: 10.3389/fpls.2020.00981] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 06/16/2020] [Indexed: 05/06/2023]
Abstract
Photosynthetic organisms fix inorganic carbon through carbon capture machinery (CCM) that regulates the assimilation and accumulation of carbon around ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). However, few constraints that govern the central carbon metabolism are regulated by the carbon capture and partitioning machinery. In order to divert the cellular metabolism toward lipids and/or biorenewables it is important to investigate and understand the molecular mechanisms of the CO2-driven carbon partitioning. In this context, strategies for enhancement of CO2 fixation which will increase the overall biomass and lipid yields, can provide clues on understanding the carbon assimilation pathway, and may lead to new targets for genetic engineering in microalgae. In the present study, we have focused on the physiological and metabolomic response occurring within marine oleaginous microalgae Microchloropsis gaditana NIES 2587, under the influence of very-low CO2 (VLC; 300 ppm, or 0.03%) and high CO2 (HC; 30,000 ppm, or 3% v/v). Our results demonstrate that HC supplementation in M. gaditana channelizes the carbon flux toward the production of long chain polyunsaturated fatty acids (LC-PUFAs) and also increases the overall biomass productivities (up to 2.0 fold). Also, the qualitative metabolomics has identified nearly 31 essential metabolites, among which there is a significant fold change observed in accumulation of sugars and alcohols such as galactose and phytol in VLC as compared to HC. In conclusion, our focus is to understand the entire carbon partitioning and metabolic regulation within these photosynthetic cell factories, which will be further evaluated through multiomics approach for enhanced productivities of biomass, biofuels, and bioproducts (B3).
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Affiliation(s)
| | | | | | | | - Pannaga Pavan Jutur
- Omics of Algae Group, Industrial Biotechnology, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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13
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Kono A, Chou TH, Radhakrishnan A, Bolla JR, Sankar K, Shome S, Su CC, Jernigan RL, Robinson CV, Yu EW, Spalding MH. Structure and function of LCI1: a plasma membrane CO 2 channel in the Chlamydomonas CO 2 concentrating mechanism. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 102:1107-1126. [PMID: 32168387 PMCID: PMC7305984 DOI: 10.1111/tpj.14745] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 01/18/2020] [Accepted: 02/20/2020] [Indexed: 05/19/2023]
Abstract
Microalgae and cyanobacteria contribute roughly half of the global photosynthetic carbon assimilation. Faced with limited access to CO2 in aquatic environments, which can vary daily or hourly, these microorganisms have evolved use of an efficient CO2 concentrating mechanism (CCM) to accumulate high internal concentrations of inorganic carbon (Ci ) to maintain photosynthetic performance. For eukaryotic algae, a combination of molecular, genetic and physiological studies using the model organism Chlamydomonas reinhardtii, have revealed the function and molecular characteristics of many CCM components, including active Ci uptake systems. Fundamental to eukaryotic Ci uptake systems are Ci transporters/channels located in membranes of various cell compartments, which together facilitate the movement of Ci from the environment into the chloroplast, where primary CO2 assimilation occurs. Two putative plasma membrane Ci transporters, HLA3 and LCI1, are reportedly involved in active Ci uptake. Based on previous studies, HLA3 clearly plays a meaningful role in HCO3- transport, but the function of LCI1 has not yet been thoroughly investigated so remains somewhat obscure. Here we report a crystal structure of the full-length LCI1 membrane protein to reveal LCI1 structural characteristics, as well as in vivo physiological studies in an LCI1 loss-of-function mutant to reveal the Ci species preference for LCI1. Together, these new studies demonstrate LCI1 plays an important role in active CO2 uptake and that LCI1 likely functions as a plasma membrane CO2 channel, possibly a gated channel.
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Affiliation(s)
- Alfredo Kono
- Department of Genetics, Developmental and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Tsung-Han Chou
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA
- Present address: WM Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Abhijith Radhakrishnan
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
- Present address: Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Jani Reddy Bolla
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, South Park Road, OX1 3QZ, UK
| | - Kannan Sankar
- Bioinformatics and Computational Biology Interdepartmental Graduate Program, Iowa State University, Ames, IA 50011, USA
| | - Sayane Shome
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Chih-Chia Su
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA
- Present address: Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Robert L. Jernigan
- Bioinformatics and Computational Biology Interdepartmental Graduate Program, Iowa State University, Ames, IA 50011, USA
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Carol V. Robinson
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, South Park Road, OX1 3QZ, UK
| | - Edward W. Yu
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
- Present address: Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Martin H. Spalding
- Department of Genetics, Developmental and Cell Biology, Iowa State University, Ames, IA 50011, USA
- To whom correspondence should be addressed.
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14
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Kono A, Spalding MH. LCI1, a Chlamydomonas reinhardtii plasma membrane protein, functions in active CO 2 uptake under low CO 2. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 102:1127-1141. [PMID: 32248584 DOI: 10.1111/tpj.14761] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 01/16/2020] [Accepted: 03/18/2020] [Indexed: 05/11/2023]
Abstract
In response to high CO2 environmental variability, green algae, such as Chlamydomonas reinhardtii, have evolved multiple physiological states dictated by external CO2 concentration. Genetic and physiological studies demonstrated that at least three CO2 physiological states, a high CO2 (0.5-5% CO2 ), a low CO2 (0.03-0.4% CO2 ) and a very low CO2 (< 0.02% CO2 ) state, exist in Chlamydomonas. To acclimate in the low and very low CO2 states, Chlamydomonas induces a sophisticated strategy known as a CO2 -concentrating mechanism (CCM) that enables proliferation and survival in these unfavorable CO2 environments. Active uptake of Ci from the environment is a fundamental aspect in the Chlamydomonas CCM, and consists of CO2 and HCO3- uptake systems that play distinct roles in low and very low CO2 acclimation states. LCI1, a putative plasma membrane Ci transporter, has been linked through conditional overexpression to active Ci uptake. However, both the role of LCI1 in various CO2 acclimation states and the species of Ci , HCO3- or CO2 , that LCI1 transports remain obscure. Here we report the impact of an LCI1 loss-of-function mutant on growth and photosynthesis in different genetic backgrounds at multiple pH values. These studies show that LCI1 appears to be associated with active CO2 uptake in low CO2 , especially above air-level CO2 , and that any LCI1 role in very low CO2 is minimal.
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Affiliation(s)
- Alfredo Kono
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, 50011, USA
| | - Martin H Spalding
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, 50011, USA
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15
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Toyokawa C, Yamano T, Fukuzawa H. Pyrenoid Starch Sheath Is Required for LCIB Localization and the CO 2-Concentrating Mechanism in Green Algae. PLANT PHYSIOLOGY 2020; 182:1883-1893. [PMID: 32041908 PMCID: PMC7140920 DOI: 10.1104/pp.19.01587] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 01/24/2020] [Indexed: 05/09/2023]
Abstract
Aquatic photosynthetic organisms induce a CO2-concentrating mechanism (CCM) to overcome the difficulty of acquiring inorganic carbon under CO2-limiting conditions. As part of the CCM, the CO2-fixing enzyme Rubisco is enriched in the pyrenoid located in the chloroplast, and, in many green algae, several thick starch plates surround the pyrenoid to form a starch sheath. In Chlamydomonas reinhardtii, low-CO2-inducible protein B (LCIB), which is an essential factor for the CCM, displays altered cellular localization in response to a decrease in environmental CO2 concentration, moving from dispersed throughout the chloroplast stroma to around the pyrenoid. However, the mechanism behind LCIB migration remains poorly understood. Here, we report the characteristics of an Isoamylase1-less mutant (4-D1), which shows aberrant LCIB localization and starch sheath formation. Under very-low-CO2 conditions, 4-D1 showed retarded growth, lower photosynthetic affinities against inorganic carbon, and a decreased accumulation level of the HCO3 - transporter HLA3. The aberrant localization of LCIB was also observed in another starch-sheathless mutant sta11-1, but not in sta2-1, which possesses a thinned starch sheath. These results suggest that the starch sheath around the pyrenoid is required for the correct localization of LCIB and for the operation of CCM.
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Affiliation(s)
- Chihana Toyokawa
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan
| | - Takashi Yamano
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan
| | - Hideya Fukuzawa
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan
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16
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Li X, Patena W, Fauser F, Jinkerson RE, Saroussi S, Meyer MT, Ivanova N, Robertson JM, Yue R, Zhang R, Vilarrasa-Blasi J, Wittkopp TM, Ramundo S, Blum SR, Goh A, Laudon M, Srikumar T, Lefebvre PA, Grossman AR, Jonikas MC. A genome-wide algal mutant library and functional screen identifies genes required for eukaryotic photosynthesis. Nat Genet 2019. [PMID: 30886426 DOI: 10.1038/s41588-019-0370-376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Photosynthetic organisms provide food and energy for nearly all life on Earth, yet half of their protein-coding genes remain uncharacterized1,2. Characterization of these genes could be greatly accelerated by new genetic resources for unicellular organisms. Here we generated a genome-wide, indexed library of mapped insertion mutants for the unicellular alga Chlamydomonas reinhardtii. The 62,389 mutants in the library, covering 83% of nuclear protein-coding genes, are available to the community. Each mutant contains unique DNA barcodes, allowing the collection to be screened as a pool. We performed a genome-wide survey of genes required for photosynthesis, which identified 303 candidate genes. Characterization of one of these genes, the conserved predicted phosphatase-encoding gene CPL3, showed that it is important for accumulation of multiple photosynthetic protein complexes. Notably, 21 of the 43 higher-confidence genes are novel, opening new opportunities for advances in understanding of this biogeochemically fundamental process. This library will accelerate the characterization of thousands of genes in algae, plants, and animals.
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Affiliation(s)
- Xiaobo Li
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
- School of Life Sciences, Westlake Institute for Advanced Study, Westlake University, Hangzhou, China
| | - Weronika Patena
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Friedrich Fauser
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Robert E Jinkerson
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, CA, USA
| | - Shai Saroussi
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Moritz T Meyer
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Nina Ivanova
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Jacob M Robertson
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Rebecca Yue
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Ru Zhang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | | | - Tyler M Wittkopp
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
- Department of Biology, Stanford University, Stanford, CA, USA
- Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Silvia Ramundo
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Sean R Blum
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Audrey Goh
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Matthew Laudon
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, USA
| | - Tharan Srikumar
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Paul A Lefebvre
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, USA
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Martin C Jonikas
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA.
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17
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A genome-wide algal mutant library and functional screen identifies genes required for eukaryotic photosynthesis. Nat Genet 2019; 51:627-635. [PMID: 30886426 PMCID: PMC6636631 DOI: 10.1038/s41588-019-0370-6] [Citation(s) in RCA: 142] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Accepted: 02/08/2019] [Indexed: 12/22/2022]
Abstract
Photosynthetic organisms provide food and energy for nearly all life on Earth, yet half of their protein-coding genes remain uncharacterized1,2. Characterization of these genes could be greatly accelerated by new genetic resources for unicellular organisms. Here, we generated a genome-wide, indexed library of mapped insertion mutants for the unicellular alga Chlamydomonas reinhardtii. The 62,389 mutants in the library, covering 83% of nuclear, protein-coding genes, are available to the community. Each mutant contains unique DNA barcodes, allowing the collection to be screened as a pool. We performed a genome-wide survey of genes required for photosynthesis, which identified 303 candidate genes. Characterization of one of these genes, the conserved predicted phosphatase-encoding gene CPL3, showed it is important for accumulation of multiple photosynthetic protein complexes. Notably, 21 of the 43 highest-confidence genes are novel, opening new opportunities for advances in our understanding of this biogeochemically fundamental process. This library will accelerate the characterization of thousands of genes in algae, plants and animals. Generation of a library of 62,389 mapped insertion mutants for the unicellular alga Chlamydomonas reinhardtii enables screening for genes required for photosynthesis and the identification of 303 candidate genes.
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18
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Zhang W, Zhong H, Lu H, Zhang Y, Deng X, Huang K, Duanmu D. Characterization of Ferredoxin-Dependent Biliverdin Reductase PCYA1 Reveals the Dual Function in Retrograde Bilin Biosynthesis and Interaction With Light-Dependent Protochlorophyllide Oxidoreductase LPOR in Chlamydomonas reinhardtii. FRONTIERS IN PLANT SCIENCE 2018; 9:676. [PMID: 29875782 PMCID: PMC5974162 DOI: 10.3389/fpls.2018.00676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 05/03/2018] [Indexed: 05/27/2023]
Abstract
Bilins are linear tetrapyrroles commonly used as chromophores of phycobiliproteins and phytochromes for light-harvesting or light-sensing in photosynthetic organisms. Many eukaryotic algae lack both phycobiliproteins and phytochromes, but retain the bilin biosynthetic enzymes including heme oxygenase (HO/HMOX) and ferredoxin-dependent biliverdin reductase (FDBR). Previous studies on Chlamydomonas reinhardtii heme oxygenase mutant (hmox1) have shown that bilins are not only essential retrograde signals to mitigate oxidative stress during diurnal dark-to-light transitions, they are also required for chlorophyll accumulation and maintenance of a functional photosynthetic apparatus in the light. However, the underlying mechanism of bilin-mediated regulation of chlorophyll biosynthesis is unclear. In this study, Chlamydomonas phycocyanobilin:ferredoxin oxidoreductase PCYA1 FDBR domain was found to specifically interact with the rate-limiting chlorophyll biosynthetic enzyme LPOR (light-dependent protochlorophyllide oxidoreductase). PCYA1 is partially associated with chloroplast envelope membrane, consistent with the observed export of bilin from chloroplast to cytosol by cytosolic expression of a bilin-binding reporter protein in Chlamydomonas. Both the pcya1-1 mutant with the carboxyl-terminal extension of PCYA1 eliminated and efficient knockdown of PCYA1 expression by artificial microRNA exhibited no significant impact on algal phototrophic growth and photosynthetic proteins accumulation, indicating that the conserved FDBR domain is sufficient and minimally required for bilin biosynthesis and functioning. Taken together, these studies provide novel insights into the regulatory role of PCYA1 in chlorophyll biosynthesis via interaction with key Chl biosynthetic enzyme.
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Affiliation(s)
- Weiqing Zhang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Huan Zhong
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Hui Lu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yuxiang Zhang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xuan Deng
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Kaiyao Huang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Deqiang Duanmu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
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19
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DiMario RJ, Machingura MC, Waldrop GL, Moroney JV. The many types of carbonic anhydrases in photosynthetic organisms. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 268:11-17. [PMID: 29362079 DOI: 10.1016/j.plantsci.2017.12.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 11/22/2017] [Accepted: 12/02/2017] [Indexed: 05/24/2023]
Abstract
Carbonic anhydrases (CAs) are enzymes that catalyze the interconversion of CO2 and HCO3-. In nature, there are multiple families of CA, designated with the Greek letters α through θ. CAs are ubiquitous in plants, algae and photosynthetic bacteria, often playing essential roles in the CO2 concentrating mechanisms (CCMs) which enhance the delivery of CO2 to Rubisco. As algal CCMs become better characterized, it is clear that different types of CAs are playing the same role in different algae. For example, an α-CA catalyzes the conversion of accumulated HCO3- to CO2 in the green alga Chlamydomonas reinhardtii, while a θ-CA performs the same function in the diatom Phaeodactylum tricornutum. In this review we argue that, in addition to its role of delivering CO2 for photosynthesis, other metabolic roles of CA have likely changed as the Earth's atmospheric CO2 level decreased. Since the algal and plant lineages diverged well before the decrease in atmospheric CO2, it is likely that plant, algae and photosynthetic bacteria all adapted independently to the drop in atmospheric CO2. In light of this, we will discuss how the roles of CAs may have changed over time, focusing on the role of CA in pH regulation, how CAs affect CO2 supply for photosynthesis and how CAs may help in the delivery of HCO3- for other metabolic reactions.
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Affiliation(s)
- Robert J DiMario
- School of Biological Sciences, Molecular Plant Sciences, Washington State University, Pullman, WA 99164, United States.
| | - Marylou C Machingura
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States.
| | - Grover L Waldrop
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States.
| | - James V Moroney
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States.
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20
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Mackinder LCM. The Chlamydomonas CO 2 -concentrating mechanism and its potential for engineering photosynthesis in plants. THE NEW PHYTOLOGIST 2018; 217:54-61. [PMID: 28833179 DOI: 10.1111/nph.14749] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 07/04/2017] [Indexed: 05/19/2023]
Abstract
Contents Summary I. Introduction 54 II. Recent advances in our understanding of the Chlamydomonas CCM 55 III. Current gaps in our understanding of the Chlamydomonas CCM 58 IV. Approaches to rapidly advance our understanding of the Chlamydomonas CCM 58 V. Engineering a CCM into higher plants 58 VI. Conclusion and outlook 59 Acknowledgements 60 References 60 SUMMARY: To meet the food demands of a rising global population, innovative strategies are required to increase crop yields. Improvements in plant photosynthesis by genetic engineering show considerable potential towards this goal. One prospective approach is to introduce a CO2 -concentrating mechanism into crop plants to increase carbon fixation by supplying the central carbon-fixing enzyme, Rubisco, with a higher concentration of its substrate, CO2 . A promising donor organism for the molecular machinery of this mechanism is the eukaryotic alga Chlamydomonas reinhardtii. This review summarizes the recent advances in our understanding of carbon concentration in Chlamydomonas, outlines the most pressing gaps in our knowledge and discusses strategies to transfer a CO2 -concentrating mechanism into higher plants to increase photosynthetic performance.
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21
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Tomar V, Sidhu GK, Nogia P, Mehrotra R, Mehrotra S. Regulatory components of carbon concentrating mechanisms in aquatic unicellular photosynthetic organisms. PLANT CELL REPORTS 2017; 36:1671-1688. [PMID: 28780704 DOI: 10.1007/s00299-017-2191-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 07/31/2017] [Indexed: 06/07/2023]
Abstract
This review provides an insight into the regulation of the carbon concentrating mechanisms (CCMs) in lower organisms like cyanobacteria, proteobacteria, and algae. CCMs evolved as a mechanism to concentrate CO2 at the site of primary carboxylating enzyme Ribulose-1, 5-bisphosphate carboxylase oxygenase (Rubisco), so that the enzyme could overcome its affinity towards O2 which leads to wasteful processes like photorespiration. A diverse set of CCMs exist in nature, i.e., carboxysomes in cyanobacteria and proteobacteria; pyrenoids in algae and diatoms, the C4 system, and Crassulacean acid metabolism in higher plants. Prime regulators of CCM in most of the photosynthetic autotrophs belong to the LysR family of transcriptional regulators, which regulate the activity of the components of CCM depending upon the ambient CO2 concentrations. Major targets of these regulators are carbonic anhydrase and inorganic carbon uptake systems (CO2 and HCO3- transporters) whose activities are modulated either at transcriptional level or by changes in the levels of their co-regulatory metabolites. The article provides information on the localization of the CCM components as well as their function and participation in the development of an efficient CCM. Signal transduction cascades leading to activation/inactivation of inducible CCM components on perception of low/high CO2 stimuli have also been brought into picture. A detailed study of the regulatory components can aid in identifying the unraveled aspects of these mechanisms and hence provide information on key molecules that need to be explored to further provide a clear understanding of the mechanism under study.
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Affiliation(s)
- Vandana Tomar
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333031, Rajasthan, India
| | - Gurpreet Kaur Sidhu
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333031, Rajasthan, India
| | - Panchsheela Nogia
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333031, Rajasthan, India
| | - Rajesh Mehrotra
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333031, Rajasthan, India
| | - Sandhya Mehrotra
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, 333031, Rajasthan, India.
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22
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Xu Z, Wang Y, Chen Y, Spalding MH, Dong L. Microfluidic chip for automated screening of carbon dioxide conditions for microalgal cell growth. BIOMICROFLUIDICS 2017; 11:064104. [PMID: 29204245 PMCID: PMC5699919 DOI: 10.1063/1.5012508] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 11/06/2017] [Indexed: 05/27/2023]
Abstract
This paper reports on a microfluidic device capable of screening carbon dioxide (CO2) conditions for microalgal cell growth. The device mainly consists of a microfluidic cell culture (MCC) unit, a gas concentration gradient generator (CGG), and an in-line cell growth optical measurement unit. The MCC unit is structured with multiple aqueous-filled cell culture channels at the top layer, multiple CO2 flow channels at the bottom layer, and a commercial hydrophobic gas semipermeable membrane sandwiched between the two channel layers. The CGG unit provides different CO2 concentrations to support photosynthesis of microalgae in the culture channels. The integration of the commercial gas semipermeable membrane into the cell culture device allows rapid mass transport and uniform distribution of CO2 inside the culture medium without using conventional agitation-assisted convection methods, because the diffusion of CO2 from the gas flow channels to the culture channels is fast over a small length scale. In addition, automated in-line monitoring of microalgal cell growth is realized via the optical measurement unit that is able to detect changes in the light intensity transmitted through the cell culture in the culture channels. The microfluidic device also allows a simple grayscale analysis method to quantify the cell growth. The utility of the system is validated by growing Chlamydomonas reinhardtii cells under different low or very-low CO2 levels below the nominal ambient CO2 concentration.
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Affiliation(s)
- Zhen Xu
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011, USA
| | - Yingjun Wang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Yuncong Chen
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011, USA
| | - Martin H Spalding
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Liang Dong
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011, USA
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23
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Mackinder LCM, Chen C, Leib RD, Patena W, Blum SR, Rodman M, Ramundo S, Adams CM, Jonikas MC. A Spatial Interactome Reveals the Protein Organization of the Algal CO 2-Concentrating Mechanism. Cell 2017; 171:133-147.e14. [PMID: 28938113 PMCID: PMC5616186 DOI: 10.1016/j.cell.2017.08.044] [Citation(s) in RCA: 160] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/30/2017] [Accepted: 08/22/2017] [Indexed: 11/20/2022]
Abstract
Approximately one-third of global CO2 fixation is performed by eukaryotic algae. Nearly all algae enhance their carbon assimilation by operating a CO2-concentrating mechanism (CCM) built around an organelle called the pyrenoid, whose protein composition is largely unknown. Here, we developed tools in the model alga Chlamydomonas reinhardtii to determine the localizations of 135 candidate CCM proteins and physical interactors of 38 of these proteins. Our data reveal the identity of 89 pyrenoid proteins, including Rubisco-interacting proteins, photosystem I assembly factor candidates, and inorganic carbon flux components. We identify three previously undescribed protein layers of the pyrenoid: a plate-like layer, a mesh layer, and a punctate layer. We find that the carbonic anhydrase CAH6 is in the flagella, not in the stroma that surrounds the pyrenoid as in current models. These results provide an overview of proteins operating in the eukaryotic algal CCM, a key process that drives global carbon fixation.
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Affiliation(s)
- Luke C M Mackinder
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Chris Chen
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Ryan D Leib
- Stanford University Mass Spectrometry, Stanford University, Stanford, CA 94305, USA
| | - Weronika Patena
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Sean R Blum
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Matthew Rodman
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Silvia Ramundo
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94158, USA
| | - Christopher M Adams
- Stanford University Mass Spectrometry, Stanford University, Stanford, CA 94305, USA
| | - Martin C Jonikas
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
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Matsuda Y, Hopkinson BM, Nakajima K, Dupont CL, Tsuji Y. Mechanisms of carbon dioxide acquisition and CO 2 sensing in marine diatoms: a gateway to carbon metabolism. Philos Trans R Soc Lond B Biol Sci 2017; 372:20160403. [PMID: 28717013 PMCID: PMC5516112 DOI: 10.1098/rstb.2016.0403] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2017] [Indexed: 01/03/2023] Open
Abstract
Diatoms are one of the most successful marine eukaryotic algal groups, responsible for up to 20% of the annual global CO2 fixation. The evolution of a CO2-concentrating mechanism (CCM) allowed diatoms to overcome a number of serious constraints on photosynthesis in the marine environment, particularly low [CO2]aq in seawater relative to concentrations required by the CO2 fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO), which is partly due to the slow diffusion rate of CO2 in water and a limited CO2 formation rate from [Formula: see text] in seawater. Diatoms use two alternative strategies to take up dissolved inorganic carbon (DIC) from the environment: one primarily relies on the direct uptake of [Formula: see text] through plasma-membrane type solute carrier (SLC) 4 family [Formula: see text] transporters and the other is more reliant on passive diffusion of CO2 formed by an external carbonic anhydrase (CA). Bicarbonate taken up into the cytoplasm is most likely then actively transported into the chloroplast stroma by SLC4-type transporters on the chloroplast membrane system. Bicarbonate in the stroma is converted into CO2 only in close proximity to RubisCO preventing unnecessary CO2 leakage. CAs play significant roles in mobilizing DIC as it is progressively moved towards the site of fixation. However, the evolutionary types and subcellular locations of CAs are not conserved between different diatoms, strongly suggesting that this DIC mobilization strategy likely evolved multiple times with different origins. By contrast, the recent discovery of the thylakoid luminal θ-CA indicates that the strategy to supply CO2 to RubisCO in the pyrenoid may be very similar to that of green algae, and strongly suggests convergent coevolution in CCM function of the thylakoid lumen not only among diatoms but among eukaryotic algae in general. In this review, both experimental and corresponding theoretical models of the diatom CCMs are discussed.This article is part of the themed issue 'The peculiar carbon metabolism in diatoms'.
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Affiliation(s)
- Yusuke Matsuda
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Brian M Hopkinson
- Department of Marine Sciences, University of Georgia, Athens, GA 30602, USA
| | - Kensuke Nakajima
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | | | - Yoshinori Tsuji
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1337, Japan
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Chen B, Lee K, Plucinak T, Duanmu D, Wang Y, Horken KM, Weeks DP, Spalding MH. A novel activation domain is essential for CIA5-mediated gene regulation in response to CO2 changes in Chlamydomonas reinhardtii. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Tsuji Y, Nakajima K, Matsuda Y. Molecular aspects of the biophysical CO2-concentrating mechanism and its regulation in marine diatoms. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3763-3772. [PMID: 28633304 DOI: 10.1093/jxb/erx173] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Diatoms operate a CO2-concentrating mechanism (CCM) that drives upwards of 20% of annual global primary production. Recent progress in CCM research in the marine pennate diatom Phaeodactylum tricornutum revealed that this diatom directly takes up HCO3- from seawater through low-CO2-inducible plasma membrane HCO3- transporters, which belong to the solute carrier (SLC) 4 family. Apart from this, studies of carbonic anhydrases (CAs) in diatoms have revealed considerable diversity in classes and localization among species. This strongly suggests that the CA systems, which control permeability and flux of dissolved inorganic carbon (DIC) by catalysing reversible CO2 hydration, have evolved from diverse origins. Of particular interest is the occurrence of low-CO2-inducible external CAs in the centric marine diatom Thalassiosira pseudonana, offering a strategy of CA-catalysed initial CO2 entry via passive diffusion, contrasting with active DIC transport in P. tricornutum. Molecular mechanisms to transport DIC across chloroplast envelopes are likely also through specific HCO3- transporters, although details have yet to be elucidated. Furthermore, recent discovery of a luminal θ-CA in the diatom thylakoid implied a common strategy in the mechanism to supply CO2 to RubisCO in the pyrenoid, which is conserved among green algae and some heterokontophytes. These results strongly suggest an occurrence of convergent coevolution between the pyrenoid and thylakoid membrane in aquatic photosynthesis.
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Affiliation(s)
- Yoshinori Tsuji
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Kensuke Nakajima
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Yusuke Matsuda
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1337, Japan
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Rae BD, Long BM, Förster B, Nguyen ND, Velanis CN, Atkinson N, Hee WY, Mukherjee B, Price GD, McCormick AJ. Progress and challenges of engineering a biophysical CO2-concentrating mechanism into higher plants. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3717-3737. [PMID: 28444330 DOI: 10.1093/jxb/erx133] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Growth and productivity in important crop plants is limited by the inefficiencies of the C3 photosynthetic pathway. Introducing CO2-concentrating mechanisms (CCMs) into C3 plants could overcome these limitations and lead to increased yields. Many unicellular microautotrophs, such as cyanobacteria and green algae, possess highly efficient biophysical CCMs that increase CO2 concentrations around the primary carboxylase enzyme, Rubisco, to enhance CO2 assimilation rates. Algal and cyanobacterial CCMs utilize distinct molecular components, but share several functional commonalities. Here we outline the recent progress and current challenges of engineering biophysical CCMs into C3 plants. We review the predicted requirements for a functional biophysical CCM based on current knowledge of cyanobacterial and algal CCMs, the molecular engineering tools and research pipelines required to translate our theoretical knowledge into practice, and the current challenges to achieving these goals.
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Affiliation(s)
- Benjamin D Rae
- Australian Research Council Centre of Excellence for Translational Photosynthesis
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - Benedict M Long
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - Britta Förster
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - Nghiem D Nguyen
- Australian Research Council Centre of Excellence for Translational Photosynthesis
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - Christos N Velanis
- SynthSys and Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Nicky Atkinson
- SynthSys and Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Wei Yih Hee
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - Bratati Mukherjee
- Australian Research Council Centre of Excellence for Translational Photosynthesis
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - G Dean Price
- Australian Research Council Centre of Excellence for Translational Photosynthesis
- Research School of Biology, The Australian National University, 134 Linnaeus Way, Acton ACT 2601, Australia
| | - Alistair J McCormick
- SynthSys and Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
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Pollock SV, Mukherjee B, Bajsa-Hirschel J, Machingura MC, Mukherjee A, Grossman AR, Moroney JV. A robust protocol for efficient generation, and genomic characterization of insertional mutants of Chlamydomonas reinhardtii. PLANT METHODS 2017; 13:22. [PMID: 28392829 PMCID: PMC5376698 DOI: 10.1186/s13007-017-0170-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 03/22/2017] [Indexed: 05/10/2023]
Abstract
BACKGROUND Random insertional mutagenesis of Chlamydomonas reinhardtii using drug resistance cassettes has contributed to the generation of tens of thousands of transformants in dozens of labs around the world. In many instances these insertional mutants have helped elucidate the genetic basis of various physiological processes in this model organism. Unfortunately, the insertion sites of many interesting mutants are never defined due to experimental difficulties in establishing the location of the inserted cassette in the Chlamydomonas genome. It is fairly common that several months, or even years of work are conducted with no result. Here we describe a robust method to identify the location of the inserted DNA cassette in the Chlamydomonas genome. RESULTS Insertional mutants were generated using a DNA cassette that confers paromomycin resistance. This protocol identified the cassette insertion site for greater than 80% of the transformants. In the majority of cases the insertion event was found to be simple, without large deletions of flanking genomic DNA. Multiple insertions were observed in less than 10% of recovered transformants. CONCLUSION The method is quick, relatively inexpensive and does not require any special equipment beyond an electroporator. The protocol was tailored to ensure that the sequence of the Chlamydomonas genomic DNA flanking the random insertion is consistently obtained in a high proportion of transformants. A detailed protocol is presented to aid in the experimental design and implementation of mutant screens in Chlamydomonas.
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Affiliation(s)
- Steve V. Pollock
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Bratati Mukherjee
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Joanna Bajsa-Hirschel
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Marylou C. Machingura
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Ananya Mukherjee
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA
| | - Arthur R. Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305 USA
| | - James V. Moroney
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 USA
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Wang L, Yamano T, Takane S, Niikawa Y, Toyokawa C, Ozawa SI, Tokutsu R, Takahashi Y, Minagawa J, Kanesaki Y, Yoshikawa H, Fukuzawa H. Chloroplast-mediated regulation of CO2-concentrating mechanism by Ca2+-binding protein CAS in the green alga Chlamydomonas reinhardtii. Proc Natl Acad Sci U S A 2016; 113:12586-12591. [PMID: 27791081 PMCID: PMC5098658 DOI: 10.1073/pnas.1606519113] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Aquatic photosynthetic organisms, including the green alga Chlamydomonas reinhardtii, induce a CO2-concentrating mechanism (CCM) to maintain photosynthetic activity in CO2-limiting conditions by sensing environmental CO2 and light availability. Previously, a novel high-CO2-requiring mutant, H82, defective in the induction of the CCM, was isolated. A homolog of calcium (Ca2+)-binding protein CAS, originally found in Arabidopsis thaliana, was disrupted in H82 cells. Although Arabidopsis CAS is reported to be associated with stomatal closure or immune responses via a chloroplast-mediated retrograde signal, the relationship between a Ca2+ signal and the CCM associated with the function of CAS in an aquatic environment is still unclear. In this study, the introduction of an intact CAS gene into H82 cells restored photosynthetic affinity for inorganic carbon, and RNA-seq analyses revealed that CAS could function in maintaining the expression levels of nuclear-encoded CO2-limiting-inducible genes, including the HCO3- transporters high-light activated 3 (HLA3) and low-CO2-inducible gene A (LCIA). CAS changed its localization from dispersed across the thylakoid membrane in high-CO2 conditions or in the dark to being associated with tubule-like structures in the pyrenoid in CO2-limiting conditions, along with a significant increase of the fluorescent signals of the Ca2+ indicator in the pyrenoid. Chlamydomonas CAS had Ca2+-binding activity, and the perturbation of intracellular Ca2+ homeostasis by a Ca2+-chelator or calmodulin antagonist impaired the accumulation of HLA3 and LCIA. These results suggest that Chlamydomonas CAS is a Ca2+-mediated regulator of CCM-related genes via a retrograde signal from the pyrenoid in the chloroplast to the nucleus.
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Affiliation(s)
- Lianyong Wang
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Takashi Yamano
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Shunsuke Takane
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Yuki Niikawa
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Chihana Toyokawa
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Shin-Ichiro Ozawa
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
| | - Ryutaro Tokutsu
- Division of Environmental Photobiology, National Institute for Basic Biology, Okazaki 444-8585, Japan
| | - Yuichiro Takahashi
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
| | - Jun Minagawa
- Division of Environmental Photobiology, National Institute for Basic Biology, Okazaki 444-8585, Japan
| | - Yu Kanesaki
- NODAI Genome Research Center, Tokyo University of Agriculture, Tokyo 156-8502, Japan
| | - Hirofumi Yoshikawa
- Department of Bioscience, Tokyo University of Agriculture, Tokyo 156-8502, Japan
| | - Hideya Fukuzawa
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan;
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Transcriptome profiling of the microalga Chlorella pyrenoidosa in response to different carbon dioxide concentrations. Mar Genomics 2016; 29:81-87. [PMID: 27209568 DOI: 10.1016/j.margen.2016.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 04/11/2016] [Accepted: 05/03/2016] [Indexed: 11/21/2022]
Abstract
To enrich our knowledge of carbon dioxide (CO2)-concentrating mechanism (CCM) in eukaryotic algae, we used high-throughput sequencing to investigate the transcriptome profiling of the microalga Chlorella pyrenoidosa (Chlorophyta) response to different CO2 levels. Altogether, 53.86 million (M) and 62.10M clean short reads of 100 nucleotides (nt) were generated from this microalga cultured at 4-fold air CO2 (control) and air CO2 concentrations by Illumina sequencing. A total of 32,662 unigenes were assembled from the two pooled samples. With an E-value cut-off of 1e-5, 9590, 6782, 5954, and 9092 unigenes were annotated in NR, Gene Ontology (GO), Eukaryotic Cluster of Orthologous Groups of proteins (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. After screening, 51 differentially expressed unigenes were up-regulated and 8 were down-regulated in the air CO2 group, relative to the control. The transcript levels of eight differentially expressed unigenes were validated by real-time quantitative PCR, which manifested that thioredoxin-like protein, laminin subunit beta-1, and chlorophyll a/b binding protein might be associated with the utilization of inorganic carbon at low CO2 levels.
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Wang Y, Stessman DJ, Spalding MH. The CO2 concentrating mechanism and photosynthetic carbon assimilation in limiting CO2 : how Chlamydomonas works against the gradient. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:429-448. [PMID: 25765072 DOI: 10.1111/tpj.12829] [Citation(s) in RCA: 156] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 03/08/2015] [Accepted: 03/11/2015] [Indexed: 05/04/2023]
Abstract
The CO2 concentrating mechanism (CCM) represents an effective strategy for carbon acquisition that enables microalgae to survive and proliferate when the CO2 concentration limits photosynthesis. The CCM improves photosynthetic performance by raising the CO2 concentration at the site of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), simultaneously enhancing carbon fixation and suppressing photorespiration. Active inorganic carbon (Ci) uptake, Rubisco sequestration and interconversion between different Ci species catalyzed by carbonic anhydrases (CAs) are key components in the CCM, and an array of molecular regulatory elements is present to facilitate the sensing of CO2 availability, to regulate the expression of the CCM and to coordinate interplay between photosynthetic carbon metabolism and other metabolic processes in response to limiting CO2 conditions. This review intends to integrate our current understanding of the eukaryotic algal CCM and its interaction with carbon assimilation, based largely on Chlamydomonas as a model, and to illustrate how Chlamydomonas acclimates to limiting CO2 conditions and how its CCM is regulated.
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Affiliation(s)
- Yingjun Wang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa, USA
| | - Dan J Stessman
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa, USA
| | - Martin H Spalding
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa, USA
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Gao H, Wang Y, Fei X, Wright DA, Spalding MH. Expression activation and functional analysis of HLA3, a putative inorganic carbon transporter in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 82:1-11. [PMID: 25660294 DOI: 10.1111/tpj.12788] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 01/29/2015] [Accepted: 02/02/2015] [Indexed: 05/11/2023]
Abstract
The CO2 concentrating mechanism (CCM) is a key component of the carbon assimilation strategy of aquatic microalgae. Induced by limiting CO2 and tightly regulated, the CCM enables these microalgae to respond rapidly to varying environmental CO2 supplies and to perform photosynthetic CO2 assimilation in a cost-effective way. A functional CCM in eukaryotic algae requires Rubisco sequestration, rapid interconversion between CO2 and HCO3(-) catalyzed by carbonic anhydrases (CAs), and active inorganic carbon (Ci) uptake. In the model microalga Chlamydomonas reinhardtii, a membrane protein HLA3 is proposed to be involved in active Ci uptake across the plasma membrane. In this study, we use an artificially designed transcription activator-like effector (dTALE) to activate the expression of HLA3. The successful activation of HLA3 expression demonstrates dTALE as a promising tool for gene-specific activation and investigation of gene function in Chlamydomonas. Activation of HLA3 expression in high CO2 acclimated cells, where HLA3 is not expressed, resulted in increased Ci accumulation and Ci-dependent photosynthetic O2 evolution specifically in very low CO2 concentrations, which confirms that HLA3 is indeed involved in Ci uptake, and suggests it is mainly associated with HCO3(-) transport in very low CO2 concentrations, conditions in which active CO2 uptake is highly limited.
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Affiliation(s)
- Han Gao
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
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Kroth PG. The biodiversity of carbon assimilation. JOURNAL OF PLANT PHYSIOLOGY 2015; 172:76-81. [PMID: 25239594 DOI: 10.1016/j.jplph.2014.07.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/20/2014] [Accepted: 07/21/2014] [Indexed: 06/03/2023]
Abstract
As all plastids that have been investigated so far can be traced back to endosymbiotic uptake of cyanobacteria by heterotrophic host cells, they accordingly show a high similarity regarding photosynthesis, which includes both the photosystems and the biochemical reactions around the CO2 fixation via the Calvin-Bassham cycle. Major differences between the different algal and plant groups may include the presence or absence of carbon concentrating mechanisms, pyrenoids, Rubisco activases, carbonic anhydrases as well as differences in the regulation of the Calvin-Bassham cycle. This review describes the diversity of primary carbon fixation steps in algae and plants and the respective regulatory mechanisms.
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Affiliation(s)
- Peter G Kroth
- Department of Biology, University of Konstanz, Universitaetsstr. 10, 78457 Konstanz, Germany.
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34
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Wang Y, Spalding MH. Acclimation to very low CO2: contribution of limiting CO2 inducible proteins, LCIB and LCIA, to inorganic carbon uptake in Chlamydomonas reinhardtii. PLANT PHYSIOLOGY 2014; 166:2040-50. [PMID: 25336519 PMCID: PMC4256846 DOI: 10.1104/pp.114.248294] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Accepted: 10/17/2014] [Indexed: 05/08/2023]
Abstract
The limiting-CO2 inducible CO2-concentrating mechanism (CCM) of microalgae represents an effective strategy to capture CO2 when its availability is limited. At least two limiting-CO2 acclimation states, termed low CO2 and very low CO2, have been demonstrated in the model microalga Chlamydomonas reinhardtii, and many questions still remain unanswered regarding both the regulation of these acclimation states and the molecular mechanism underlying operation of the CCM in these two states. This study examines the role of two proteins, Limiting CO2 Inducible A (LCIA; also named NAR1.2) and LCIB, in the CCM of C. reinhardtii. The identification of an LCIA-LCIB double mutant based on its inability to survive in very low CO2 suggests that both LCIA and LCIB are critical for survival in very low CO2. The contrasting effects of individual mutations in LCIB and LCIA compared with the effects of LCIB-LCIA double mutations on growth and inorganic carbon-dependent photosynthetic O2 evolution reveal distinct roles of LCIA and LCIB in the CCM. Although both LCIA and LCIB are essential for very low CO2 acclimation, LCIB appears to function in a CO2 uptake system, whereas LCIA appears to be associated with a HCO3(-) transport system. The contrasting and complementary roles of LCIA and LCIB in acclimation to low CO2 and very low CO2 suggest a possible mechanism of differential regulation of the CCM based on the inhibition of HCO3(-) transporters by moderate to high levels of CO2.
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Affiliation(s)
- Yingjun Wang
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Martin H Spalding
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, Iowa 50011
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35
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Jungnick N, Ma Y, Mukherjee B, Cronan JC, Speed DJ, Laborde SM, Longstreth DJ, Moroney JV. The carbon concentrating mechanism in Chlamydomonas reinhardtii: finding the missing pieces. PHOTOSYNTHESIS RESEARCH 2014; 121:159-73. [PMID: 24752527 DOI: 10.1007/s11120-014-0004-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 04/08/2014] [Indexed: 05/14/2023]
Abstract
The photosynthetic, unicellular green alga, Chlamydomonas reinhardtii, lives in environments that often contain low concentrations of CO2 and HCO3 (-), the utilizable forms of inorganic carbon (Ci). C. reinhardtii possesses a carbon concentrating mechanism (CCM) which can provide suitable amounts of Ci for growth and development. This CCM is induced when the CO2 concentration is at air levels or lower and is comprised of a set of proteins that allow the efficient uptake of Ci into the cell as well as its directed transport to the site where Rubisco fixes CO2 into biomolecules. While several components of the CCM have been identified in recent years, the picture is still far from complete. To further improve our knowledge of the CCM, we undertook a mutagenesis project where an antibiotic resistance cassette was randomly inserted into the C. reinhardtii genome resulting in the generation of 22,000 mutants. The mutant collection was screened using both a published PCR-based approach (Gonzalez-Ballester et al. 2011) and a phenotypic growth screen. The PCR-based screen did not rely on a colony having an altered growth phenotype and was used to identify colonies with disruptions in genes previously identified as being associated with the CCM-related gene. Eleven independent insertional mutations were identified in eight different genes showing the usefulness of this approach in generating mutations in CCM-related genes of interest as well as identifying new CCM components. Further improvements of this method are also discussed.
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Affiliation(s)
- Nadine Jungnick
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
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36
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Yamano T, Asada A, Sato E, Fukuzawa H. Isolation and characterization of mutants defective in the localization of LCIB, an essential factor for the carbon-concentrating mechanism in Chlamydomonas reinhardtii. PHOTOSYNTHESIS RESEARCH 2014; 121:193-200. [PMID: 24384670 DOI: 10.1007/s11120-013-9963-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 12/18/2013] [Indexed: 06/03/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii acclimates to low-CO2 (LC) conditions by actively transporting inorganic carbon (Ci) into the cell, resulting in an increase in photosynthetic efficiency. This mechanism is called the carbon-concentrating mechanism (CCM), and soluble protein LCIB is essential for the CCM. LCIB is localized in the vicinity of pyrenoid, a prominent structure in the chloroplast, under LC conditions in the light. In contrast, in the dark or in high-CO2 conditions, where the CCM is inactive, LCIB diffuses away from the pyrenoid. Although the functional importance of LCIB for the CCM has been shown, the significance and mechanism of the change in suborganellar localization of LCIB remain to be elucidated. In this study, we screened 13,000 DNA-tagged mutants and isolated twelve aberrant LCIB localization (abl) mutants under LC conditions. abl-1 and abl-3 with dispersed and speckled localization of LCIB in the chloroplast showed significant decreases in Ci affinity, Ci accumulation, and CO2 fixation. Ten abl mutants (abl-1, abl-3, abl-4, abl-5, abl-6, abl-7, abl-8, abl-9, abl-11, and abl-12) showed not only aberrant LCIB localization but also reduced pyrenoid sizes. Moreover, three abl mutants (abl-10, abl-11, and abl-12) showed the increased numbers of pyrenoids per cell. These results suggested that the specific LCIB localization could be related to pyrenoid development.
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Affiliation(s)
- Takashi Yamano
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan
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Wang Y, Spalding MH. LCIB in the Chlamydomonas CO2-concentrating mechanism. PHOTOSYNTHESIS RESEARCH 2014; 121:185-92. [PMID: 24307449 DOI: 10.1007/s11120-013-9956-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Accepted: 11/22/2013] [Indexed: 05/19/2023]
Abstract
The CO2-concentrating mechanism confers microalgae a versatile and efficient strategy for adapting to a wide range of environmental CO2 concentrations. LCIB, which has been demonstrated as a key player in the eukaryotic algal CO2-concentrating mechanism (CCM), is a novel protein in Chlamydomonas lacking any recognizable domain or motif, and its exact function in the CCM has not been clearly defined. The unique air-dier growth phenotype and photosynthetic characteristics in the LCIB mutants, and re-localization of LCIB between different subcellular locations in response to different levels of CO2, have indicated that the function of LCIB is closely associated with a distinct low CO2 acclimation state. Here, we review physiological and molecular evidence linking LCIB with inorganic carbon accumulation in the CCM and discuss the proposed function of LCIB in several inorganic carbon uptake/accumulation pathways. Several new molecular characteristics of LCIB also are presented.
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Affiliation(s)
- Yingjun Wang
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, 50011, USA,
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Lucker B, Kramer DM. Regulation of cyclic electron flow in Chlamydomonas reinhardtii under fluctuating carbon availability. PHOTOSYNTHESIS RESEARCH 2013; 117:449-59. [PMID: 24113925 DOI: 10.1007/s11120-013-9932-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 09/24/2013] [Indexed: 05/08/2023]
Abstract
The chloroplast must rapidly and precisely adjust photosynthetic ATP and NADPH output to meet changing metabolic demands imposed by fluctuating environmental conditions. Cyclic electron flow (CEF) around photosystem I is thought to contribute to this adjustment by providing ATP in excess of that supplied by linear electron low, balancing chloroplast energy budget when relative demand for ATP is high. We assessed the kinetics and energy production of CEF activation in Chlamydomonas reinhardtii under rapid changes of organic and inorganic carbon availability. Comparisons of transient electric field and chlorophyll fluorescence measurements indicated CEF was activated under conditions where ATP demand is expected to be high, consistent with a role in balancing the cellular ATP/NADPH budget under fluctuating environmental or metabolic conditions. CEF activation was not correlated with antenna state transitions, both in wild-type and the state transition mutant stt7-9, suggesting that CEF is rapidly regulated by allosteric or redox modulators. Comparing the CEF under ambient and high CO2 conditions suggests an increase in required energy output of approximately 1ATP/CO2 fixed, nearly sufficient to power proposed mechanistic models for the carbon-concentrating mechanism. Additionally, we see three-fold higher CEF rates in cells under steady-state conditions than cells under similar conditions with inhibited photosystem II, and up to five times higher in cells with severe depletion of inorganic carbon, implying that CEF has larger energetic capacity than predicted from some previous work.
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Affiliation(s)
- Ben Lucker
- DOE-Plant Research Laboratory, Michigan State University, S222 Plant Biology Building, East Lansing, MI, 48824-1312, USA
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Moroney JV, Jungnick N, Dimario RJ, Longstreth DJ. Photorespiration and carbon concentrating mechanisms: two adaptations to high O2, low CO2 conditions. PHOTOSYNTHESIS RESEARCH 2013; 117:121-31. [PMID: 23771683 DOI: 10.1007/s11120-013-9865-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Accepted: 05/27/2013] [Indexed: 05/19/2023]
Abstract
This review presents an overview of the two ways that cyanobacteria, algae, and plants have adapted to high O2 and low CO2 concentrations in the environment. First, the process of photorespiration enables photosynthetic organisms to recycle phosphoglycolate formed by the oxygenase reaction catalyzed by ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). Second, there are a number of carbon concentrating mechanisms that increase the CO2 concentration around Rubisco which increases the carboxylase reaction enhancing CO2 fixation. This review also presents possibilities for the beneficial modification of these processes with the goal of improving future crop yields.
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Affiliation(s)
- James V Moroney
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA,
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Winck FV, Páez Melo DO, González Barrios AF. Carbon acquisition and accumulation in microalgae Chlamydomonas: Insights from "omics" approaches. J Proteomics 2013; 94:207-18. [PMID: 24120529 DOI: 10.1016/j.jprot.2013.09.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 08/29/2013] [Accepted: 09/26/2013] [Indexed: 11/16/2022]
Abstract
UNLABELLED Understanding the processes and mechanisms of carbon acquisition and accumulation in microalgae is fundamental to enhance the cellular capabilities aimed to environmental and industrial applications. The "omics" approaches have greatly contributed to expanding the knowledge on these carbon-related cellular responses, reporting large data sets on microalgae transcriptome, proteome and metabolome. This review emphasizes the advances made on Chlamydomonas exploration; however, some knowledge acquired from studying this model organism, may be extrapolated to close algae species. The large data sets available for this organism revealed the identity of a vast range of genes and proteins which are integrating carbon-related mechanisms. Nevertheless, these data sets have also highlighted the need for integrative analysis in order to fully explore the information enclosed. Here, some of the main results from "omics" approaches which may contribute to the understanding of carbon acquisition and accumulation in Chlamydomonas were reviewed and possible applications were discussed. BIOLOGICAL SIGNIFICANCE A number of important publications in the field of "omics" technologies have been published reporting studies of the model green microalga Chlamydomonas reinhardtii and related to microalgal biomass production. However, there are only few attempts to integrate these data. Publications showing the results from "omics" approaches, such as transcriptome, metabolome and proteome, focused in the study of mechanisms of carbon acquisition and accumulation in microalgae were reviewed. This review contributes to highlight the knowledge recently generated on such "omics" studies and it discusses how these results may be important for the advance of applied sciences, such as microalgae biotechnology.
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Affiliation(s)
- Flavia Vischi Winck
- Department of Chemical Engineering, Universidad de los Andes, Grupo de Diseño de Productos y Procesos, Bogotá 111711, Colombia.
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Höhner R, Barth J, Magneschi L, Jaeger D, Niehues A, Bald T, Grossman A, Fufezan C, Hippler M. The metabolic status drives acclimation of iron deficiency responses in Chlamydomonas reinhardtii as revealed by proteomics based hierarchical clustering and reverse genetics. Mol Cell Proteomics 2013; 12:2774-90. [PMID: 23820728 PMCID: PMC3790290 DOI: 10.1074/mcp.m113.029991] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 06/04/2013] [Indexed: 11/06/2022] Open
Abstract
Iron is a crucial cofactor in numerous redox-active proteins operating in bioenergetic pathways including respiration and photosynthesis. Cellular iron management is essential to sustain sufficient energy production and minimize oxidative stress. To produce energy for cell growth, the green alga Chlamydomonas reinhardtii possesses the metabolic flexibility to use light and/or carbon sources such as acetate. To investigate the interplay between the iron-deficiency response and growth requirements under distinct trophic conditions, we took a quantitative proteomics approach coupled to innovative hierarchical clustering using different "distance-linkage combinations" and random noise injection. Protein co-expression analyses of the combined data sets revealed insights into cellular responses governing acclimation to iron deprivation and regulation associated with photosynthesis dependent growth. Photoautotrophic growth requirements as well as the iron deficiency induced specific metabolic enzymes and stress related proteins, and yet differences in the set of induced enzymes, proteases, and redox-related polypeptides were evident, implying the establishment of distinct response networks under the different conditions. Moreover, our data clearly support the notion that the iron deficiency response includes a hierarchy for iron allocation within organelles in C. reinhardtii. Importantly, deletion of a bifunctional alcohol and acetaldehyde dehydrogenase (ADH1), which is induced under low iron based on the proteomic data, attenuates the remodeling of the photosynthetic machinery in response to iron deficiency, and at the same time stimulates expression of stress-related proteins such as NDA2, LHCSR3, and PGRL1. This finding provides evidence that the coordinated regulation of bioenergetics pathways and iron deficiency response is sensitive to the cellular and chloroplast metabolic and/or redox status, consistent with systems approach data.
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Affiliation(s)
- Ricarda Höhner
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Johannes Barth
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Leonardo Magneschi
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Daniel Jaeger
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Anna Niehues
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Till Bald
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Arthur Grossman
- §Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Christian Fufezan
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Michael Hippler
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
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Valledor L, Furuhashi T, Hanak AM, Weckwerth W. Systemic cold stress adaptation of Chlamydomonas reinhardtii. Mol Cell Proteomics 2013; 12:2032-47. [PMID: 23564937 PMCID: PMC3734567 DOI: 10.1074/mcp.m112.026765] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 03/15/2013] [Indexed: 11/06/2022] Open
Abstract
Chlamydomonas reinhardtii is one of the most important model organisms nowadays phylogenetically situated between higher plants and animals (Merchant et al. 2007). Stress adaptation of this unicellular model algae is in the focus because of its relevance to biomass and biofuel production. Here, we have studied cold stress adaptation of C. reinhardtii hitherto not described for this algae whereas intensively studied in higher plants. Toward this goal, high throughput mass spectrometry was employed to integrate proteome, metabolome, physiological and cell-morphological changes during a time-course from 0 to 120 h. These data were complemented with RT-qPCR for target genes involved in central metabolism, signaling, and lipid biosynthesis. Using this approach dynamics in central metabolism were linked to cold-stress dependent sugar and autophagy pathways as well as novel genes in C. reinhardtii such as CKIN1, CKIN2 and a hitherto functionally not annotated protein named CKIN3. Cold stress affected extensively the physiology and the organization of the cell. Gluconeogenesis and starch biosynthesis pathways are activated leading to a pronounced starch and sugar accumulation. Quantitative lipid profiles indicate a sharp decrease in the lipophilic fraction and an increase in polyunsaturated fatty acids suggesting this as a mechanism of maintaining membrane fluidity. The proteome is completely remodeled during cold stress: specific candidates of the ribosome and the spliceosome indicate altered biosynthesis and degradation of proteins important for adaptation to low temperatures. Specific proteasome degradation may be mediated by the observed cold-specific changes in the ubiquitinylation system. Sparse partial least squares regression analysis was applied for protein correlation network analysis using proteins as predictors and Fv/Fm, FW, total lipids, and starch as responses. We applied also Granger causality analysis and revealed correlations between proteins and metabolites otherwise not detectable. Twenty percent of the proteins responsive to cold are uncharacterized proteins. This presents a considerable resource for new discoveries in cold stress biology in alga and plants.
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Affiliation(s)
- Luis Valledor
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
| | - Takeshi Furuhashi
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
| | - Anne-Mette Hanak
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
| | - Wolfram Weckwerth
- ‡From the Department of Molecular Systems Biology, Faculty of Life Sciences, University of Vienna, Austria, Althanstrasse 14, A-1090, Vienna, Austria
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Bach LT, Mackinder LCM, Schulz KG, Wheeler G, Schroeder DC, Brownlee C, Riebesell U. Dissecting the impact of CO2 and pH on the mechanisms of photosynthesis and calcification in the coccolithophore Emiliania huxleyi. THE NEW PHYTOLOGIST 2013; 199:121-134. [PMID: 23496417 DOI: 10.1111/nph.12225] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 02/08/2013] [Indexed: 05/15/2023]
Abstract
Coccolithophores are important calcifying phytoplankton predicted to be impacted by changes in ocean carbonate chemistry caused by the absorption of anthropogenic CO2 . However, it is difficult to disentangle the effects of the simultaneously changing carbonate system parameters (CO2 , bicarbonate, carbonate and protons) on the physiological responses to elevated CO2 . Here, we adopted a multifactorial approach at constant pH or CO2 whilst varying dissolved inorganic carbon (DIC) to determine physiological and transcriptional responses to individual carbonate system parameters. We show that Emiliania huxleyi is sensitive to low CO2 (growth and photosynthesis) and low bicarbonate (calcification) as well as low pH beyond a limited tolerance range, but is much less sensitive to elevated CO2 and bicarbonate. Multiple up-regulated genes at low DIC bear the hallmarks of a carbon-concentrating mechanism (CCM) that is responsive to CO2 and bicarbonate but not to pH. Emiliania huxleyi appears to have evolved mechanisms to respond to limiting rather than elevated CO2 . Calcification does not function as a CCM, but is inhibited at low DIC to allow the redistribution of DIC from calcification to photosynthesis. The presented data provides a significant step in understanding how E. huxleyi will respond to changing carbonate chemistry at a cellular level.
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Affiliation(s)
- Lennart T Bach
- Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), D-24105, Kiel, Germany
| | - Luke C M Mackinder
- Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), D-24105, Kiel, Germany
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK
| | - Kai G Schulz
- Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), D-24105, Kiel, Germany
| | - Glen Wheeler
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK
- Plymouth Marine Laboratory, Prospect Place, Plymouth, PL1 3DH, UK
| | - Declan C Schroeder
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK
| | - Colin Brownlee
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK
| | - Ulf Riebesell
- Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), D-24105, Kiel, Germany
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47
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Meyer M, Griffiths H. Origins and diversity of eukaryotic CO2-concentrating mechanisms: lessons for the future. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:769-86. [PMID: 23345319 DOI: 10.1093/jxb/ers390] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The importance of the eukaryotic algal CO(2)-concentrating mechanism (CCM) is considered in terms of global productivity as well as molecular phylogeny and diversity. The three major constituents comprising the CCM in the majority of eukaryotes are described. These include: (i) likely plasma- and chloroplast-membrane inorganic carbon transporters; (ii) a suite of carbonic anhydrase enzymes in strategic locations; and usually (iii) a microcompartment in which most Rubisco aggregates (the chloroplast pyrenoid). The molecular diversity of known CCM components are set against the current green algal model for their probable operation. The review then focuses on the kinetic and cystallographic interactions of Rubisco, which permit pyrenoid formation and CCM function. Firstly, we consider observations that surface residues of the Rubisco small subunit directly condition Rubisco aggregation and pyrenoid formation. Secondly, we reanalyse the phylogenetic progression in green Rubisco kinetic properties, and suggest that Rubisco substrate selectivity (the specificity factor, S(rel), and affinity for CO(2), K(c)) demonstrate a systematic relaxation, which directly relates to the origins and effectiveness of a CCM. Finally, we consider the implications of eukaryotic CCM regulation and minimum components needed for introduction into higher plants as a possible means to enhance crop productivity in the future.
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Affiliation(s)
- Moritz Meyer
- Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK.
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48
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Longworth J, Noirel J, Pandhal J, Wright PC, Vaidyanathan S. HILIC- and SCX-Based Quantitative Proteomics of Chlamydomonas reinhardtii during Nitrogen Starvation Induced Lipid and Carbohydrate Accumulation. J Proteome Res 2012; 11:5959-71. [DOI: 10.1021/pr300692t] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Joseph Longworth
- ChELSI Institute,
Department of Chemical and Biological Engineering, The University of Sheffield, Mappin Street, Sheffield, S1
3JD, United Kingdom
| | - Josselin Noirel
- ChELSI Institute,
Department of Chemical and Biological Engineering, The University of Sheffield, Mappin Street, Sheffield, S1
3JD, United Kingdom
| | - Jagroop Pandhal
- ChELSI Institute,
Department of Chemical and Biological Engineering, The University of Sheffield, Mappin Street, Sheffield, S1
3JD, United Kingdom
| | - Phillip C. Wright
- ChELSI Institute,
Department of Chemical and Biological Engineering, The University of Sheffield, Mappin Street, Sheffield, S1
3JD, United Kingdom
| | - Seetharaman Vaidyanathan
- ChELSI Institute,
Department of Chemical and Biological Engineering, The University of Sheffield, Mappin Street, Sheffield, S1
3JD, United Kingdom
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49
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Brueggeman AJ, Gangadharaiah DS, Cserhati MF, Casero D, Weeks DP, Ladunga I. Activation of the carbon concentrating mechanism by CO2 deprivation coincides with massive transcriptional restructuring in Chlamydomonas reinhardtii. THE PLANT CELL 2012; 24:1860-75. [PMID: 22634764 PMCID: PMC3442574 DOI: 10.1105/tpc.111.093435] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 03/02/2012] [Accepted: 05/06/2012] [Indexed: 05/19/2023]
Abstract
A CO(2)-concentrating mechanism (CCM) is essential for the growth of most eukaryotic algae under ambient (392 ppm) and very low (<100 ppm) CO(2) concentrations. In this study, we used replicated deep mRNA sequencing and regulatory network reconstruction to capture a remarkable scope of changes in gene expression that occurs when Chlamydomonas reinhardtii cells are shifted from high to very low levels of CO(2) (≤100 ppm). CCM induction 30 to 180 min post-CO(2) deprivation coincides with statistically significant changes in the expression of an astonishing 38% (5884) of the 15,501 nonoverlapping C. reinhardtii genes. Of these genes, 1088 genes were induced and 3828 genes were downregulated by a log(2) factor of 2. The latter indicate a global reduction in photosynthesis, protein synthesis, and energy-related biochemical pathways. The magnitude of transcriptional rearrangement and its major patterns are robust as analyzed by three different statistical methods. De novo DNA motif discovery revealed new putative binding sites for Myeloid oncogene family transcription factors potentially involved in activating low CO(2)-induced genes. The (CA)(n) repeat (9 ≤ n ≤ 25) is present in 29% of upregulated genes but almost absent from promoters of downregulated genes. These discoveries open many avenues for new research.
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Affiliation(s)
- Andrew J. Brueggeman
- Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0665
| | | | - Matyas F. Cserhati
- Department of Statistics, University of Nebraska, Lincoln, Nebraska 68588-0665
| | - David Casero
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
| | - Donald P. Weeks
- Department of Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0665
| | - Istvan Ladunga
- Department of Statistics, University of Nebraska, Lincoln, Nebraska 68588-0665
- Address correspondence to
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50
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Fang W, Si Y, Douglass S, Casero D, Merchant SS, Pellegrini M, Ladunga I, Liu P, Spalding MH. Transcriptome-wide changes in Chlamydomonas reinhardtii gene expression regulated by carbon dioxide and the CO2-concentrating mechanism regulator CIA5/CCM1. THE PLANT CELL 2012; 24:1876-93. [PMID: 22634760 PMCID: PMC3442575 DOI: 10.1105/tpc.112.097949] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 03/12/2012] [Accepted: 05/14/2012] [Indexed: 05/18/2023]
Abstract
We used RNA sequencing to query the Chlamydomonas reinhardtii transcriptome for regulation by CO(2) and by the transcription regulator CIA5 (CCM1). Both CO(2) and CIA5 are known to play roles in acclimation to low CO(2) and in induction of an essential CO(2)-concentrating mechanism (CCM), but less is known about their interaction and impact on the whole transcriptome. Our comparison of the transcriptome of a wild type versus a cia5 mutant strain under three different CO(2) conditions, high CO(2) (5%), low CO(2) (0.03 to 0.05%), and very low CO(2) (<0.02%), provided an entry into global changes in the gene expression patterns occurring in response to the interaction between CO(2) and CIA5. We observed a massive impact of CIA5 and CO(2) on the transcriptome, affecting almost 25% of all Chlamydomonas genes, and we discovered an array of gene clusters with distinctive expression patterns that provide insight into the regulatory interaction between CIA5 and CO(2). Several individual clusters respond primarily to either CIA5 or CO(2), providing access to genes regulated by one factor but decoupled from the other. Three distinct clusters clearly associated with CCM-related genes may represent a rich source of candidates for new CCM components, including a small cluster of genes encoding putative inorganic carbon transporters.
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Affiliation(s)
- Wei Fang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011-3260, USA.
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