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Rredhi A, Petersen J, Wagner V, Vuong T, Li W, Li W, Schrader L, Mittag M. The UV-A Receptor CRY-DASH1 Up- and Downregulates Proteins Involved in Different Plastidial Pathways. J Mol Biol 2024; 436:168271. [PMID: 37699454 DOI: 10.1016/j.jmb.2023.168271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 08/18/2023] [Accepted: 09/06/2023] [Indexed: 09/14/2023]
Abstract
Algae encode up to five different types of cryptochrome photoreceptors. So far, relatively little is known about the biological functions of the DASH (Drosophila, Arabidopsis, Synechocystis and Homo)-type cryptochromes. The green alga Chlamydomonas reinhardtii encodes two of them. CRY-DASH1 also called DCRY1 has its maximal absorption peak in the UV-A range. It is localized in the chloroplast and plays an important role in balancing the photosynthetic machinery. Here, we performed a comparative analysis of chloroplast proteins from wild type and a knockout mutant of CRY-DASH1 named cry-dash1mut, using label-free quantitative proteomics as well as immunoblotting. Our results show upregulation of enzymes involved in specific pathways in the mutant including key enzymes of chlorophyll and carotenoid biosynthesis consistent with increased levels of photosynthetic pigments in cry-dash1mut. There is also an increase in certain redox as well as photosystem I and II proteins, including D1. Strikingly, CRY-DASH1 is coregulated in a D1 deletion mutant, where its amount is increased. In contrast, key proteins of the central carbon metabolism, including glycolysis/gluconeogenesis, dark fermentation and the oxidative pentose phosphate pathway are downregulated in cry-dash1mut. Similarly, enzymes of histidine biosynthesis are downregulated in cry-dash1mut leading to a reduction in the amount of free histidine. Yet, transcripts encoding for several of these proteins are at a similar level in the wild type and cry-dash1mut or even opposite. We show that CRY-DASH1 can bind to RNA, taking the psbA RNA encoding D1 as target. These data suggest that CRY-DASH1 regulates plastidial metabolic pathways at the posttranscriptional level.
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Affiliation(s)
- Anxhela Rredhi
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Jan Petersen
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany. https://twitter.com/1anPetersen
| | - Volker Wagner
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Trang Vuong
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany. https://twitter.com/trangha593
| | - Wenshuang Li
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Wei Li
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Laura Schrader
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, 07743 Jena, Germany.
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2
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Chen Z, Li M, Liu S, Chen X, Zhang W, Zhu Q, Kohnen MV, Wang Q. The Function and Photoregulatory Mechanisms of Cryptochromes From Moso Bamboo ( Phyllostachys edulis). FRONTIERS IN PLANT SCIENCE 2022; 13:866057. [PMID: 35432389 PMCID: PMC9006058 DOI: 10.3389/fpls.2022.866057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 03/07/2022] [Indexed: 06/14/2023]
Abstract
Light is one of the most important environmental factors affecting growth and geographic distribution of forestry plants. Moso bamboo is the largest temperate bamboo on earth and an important non-woody forestry species that serves not only important functions in the economy of rural areas but also carbon sequestration in the world. Due to its decades-long reproductive timing, the germplasm of moso bamboo cannot be readily improved by conventional breeding methods, arguing for a greater need to study the gene function and regulatory mechanisms of this species. We systematically studied the photoregulatory mechanisms of the moso bamboo (Phyllostachys edulis) cryptochrome 1, PheCRY1. Our results show that, similar to its Arabidopsis counterpart, the bamboo PheCRY1s are functionally restricted to the blue light inhibition of cell elongation without an apparent activity in promoting floral initiation. We demonstrate that PheCRY1s undergo light-dependent oligomerization that is inhibited by PheBIC1s, and light-dependent phosphorylation that is catalyzed by PhePPKs. We hypothesize that light-induced phosphorylation of PheCRY1s facilitate their degradation, which control availability of the PheCRY1 proteins and photosensitivity of bamboo plants. Our results demonstrate the evolutionary conservation of not only the function but also photoregulatory mechanism of PheCRY1 in this monocot forestry species.
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Affiliation(s)
- Ziyin Chen
- College of Forestry, Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Min Li
- College of Forestry, Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Siyuan Liu
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaojie Chen
- College of Forestry, Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Wenxiang Zhang
- College of Forestry, Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Qiang Zhu
- College of Forestry, Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Markus V Kohnen
- College of Forestry, Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Qin Wang
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
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Wang X, Meng C, Zhang H, Xing W, Cao K, Zhu B, Zhang C, Sun F, Gao Z. Transcriptomic and Proteomic Characterizations of the Molecular Response to Blue Light and Salicylic Acid in Haematococcus pluvialis. Mar Drugs 2021; 20:md20010001. [PMID: 35049856 PMCID: PMC8780009 DOI: 10.3390/md20010001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 12/13/2022] Open
Abstract
Haematococcus pluvialis accumulates a large amount of astaxanthin under various stresses, e.g., blue light and salicylic acid (SA). However, the metabolic response of H. pluvialis to blue light and SA is still unclear. We investigate the effects of blue light and SA on the metabolic response in H. pluvialis using both transcriptomic and proteomic sequencing analyses. The largest numbers of differentially expressed proteins (DEPs; 324) and differentially expressed genes (DEGs; 13,555) were identified on day 2 and day 7 of the treatment with blue light irradiation (150 μmol photons m−2s−1), respectively. With the addition of SA (2.5 mg/L), a total of 63 DEPs and 11,638 DEGs were revealed on day 2 and day 7, respectively. We further analyzed the molecular response in five metabolic pathways related to astaxanthin synthesis, including the astaxanthin synthesis pathway, the fatty acid synthesis pathway, the heme synthesis pathway, the reactive oxygen species (ROS) clearance pathway, and the cell wall biosynthesis pathway. Results show that blue light causes a significant down-regulation of the expression of key genes involved in astaxanthin synthesis and significantly increases the expression of heme oxygenase, which shows decreased expression by the treatment with SA. Our study provides novel insights into the production of astaxanthin by H. pluvialis treated with blue light and SA.
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Affiliation(s)
- Xiaodong Wang
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China; (X.W.); (C.M.); (W.X.); (K.C.); (B.Z.); (C.Z.)
| | - Chunxiao Meng
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China; (X.W.); (C.M.); (W.X.); (K.C.); (B.Z.); (C.Z.)
| | - Hao Zhang
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China;
| | - Wei Xing
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China; (X.W.); (C.M.); (W.X.); (K.C.); (B.Z.); (C.Z.)
| | - Kai Cao
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China; (X.W.); (C.M.); (W.X.); (K.C.); (B.Z.); (C.Z.)
| | - Bingkui Zhu
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China; (X.W.); (C.M.); (W.X.); (K.C.); (B.Z.); (C.Z.)
| | - Chengsong Zhang
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo 255049, China; (X.W.); (C.M.); (W.X.); (K.C.); (B.Z.); (C.Z.)
| | - Fengjie Sun
- School of Science and Technology, Georgia Gwinnett College, 1000 University Center Lane, Lawrenceville, GA 30043, USA
- Correspondence: (F.S.); (Z.G.)
| | - Zhengquan Gao
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China;
- Correspondence: (F.S.); (Z.G.)
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Goett-Zink L, Kottke T. Plant Cryptochromes Illuminated: A Spectroscopic Perspective on the Mechanism. Front Chem 2021; 9:780199. [PMID: 34900940 PMCID: PMC8653763 DOI: 10.3389/fchem.2021.780199] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/05/2021] [Indexed: 11/13/2022] Open
Abstract
Plant cryptochromes are central blue light receptors for the control of land plant and algal development including the circadian clock and the cell cycle. Cryptochromes share a photolyase homology region with about 500 amino acids and bind the chromophore flavin adenine dinucleotide. Characteristic for plant cryptochromes is a conserved aspartic acid close to flavin and an exceptionally long C-terminal extension. The mechanism of activation by excitation and reduction of the chromophore flavin adenine dinucleotide has been controversially discussed for many years. Various spectroscopic techniques have contributed to our understanding of plant cryptochromes by providing high time resolution, ambient conditions and even in-cell approaches. As a result, unifying and differing aspects of photoreaction and signal propagation have been revealed in comparison to members from other cryptochrome subfamilies. Here, we review the insight from spectroscopy on the flavin photoreaction in plant cryptochromes and present the current models on the signal propagation from flavin reduction to dissociation of the C-terminal extension.
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Affiliation(s)
- Lukas Goett-Zink
- Department of Chemistry, Bielefeld University, Bielefeld, Germany
| | - Tilman Kottke
- Department of Chemistry, Bielefeld University, Bielefeld, Germany.,Biophysical Chemistry and Diagnostics, Medical School OWL, Bielefeld University, Bielefeld, Germany
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Petersen J, Rredhi A, Szyttenholm J, Oldemeyer S, Kottke T, Mittag M. The World of Algae Reveals a Broad Variety of Cryptochrome Properties and Functions. FRONTIERS IN PLANT SCIENCE 2021; 12:766509. [PMID: 34790217 PMCID: PMC8591175 DOI: 10.3389/fpls.2021.766509] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 10/11/2021] [Indexed: 05/25/2023]
Abstract
Algae are photosynthetic eukaryotic (micro-)organisms, lacking roots, leaves, and other organs that are typical for land plants. They live in freshwater, marine, or terrestrial habitats. Together with the cyanobacteria they contribute to about half of global carbon fixation. As primary producers, they are at the basis of many food webs and they are involved in biogeochemical processes. Algae are evolutionarily distinct and are derived either by primary (e.g., green and red algae) or secondary endosymbiosis (e.g., diatoms, dinoflagellates, and brown algae). Light is a key abiotic factor needed to maintain the fitness of algae as it delivers energy for photosynthesis, regulates algal cell- and life cycles, and entrains their biological clocks. However, excess light can also be harmful, especially in the ultraviolet range. Among the variety of receptors perceiving light information, the cryptochromes originally evolved as UV-A and blue-light receptors and have been found in all studied algal genomes so far. Yet, the classification, biophysical properties, wavelength range of absorbance, and biological functions of cryptochromes are remarkably diverse among algal species, especially when compared to cryptochromes from land plants or animals.
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Affiliation(s)
- Jan Petersen
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Anxhela Rredhi
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Julie Szyttenholm
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Sabine Oldemeyer
- Experimental Molecular Biophysics, Department of Physics, Freie Universität Berlin, Berlin, Germany
| | - Tilman Kottke
- Department of Chemistry, Bielefeld University, Bielefeld, Germany
- Biophysical Chemistry and Diagnostics, Medical School OWL, Bielefeld University, Bielefeld, Germany
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
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6
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Chen W, Zheng L, Dong J, Ge H, Huang X, Wang G, Huang C, Wang Y, Lu D, Xu W, Wang Y. A Systematic Survey of the Light/Dark-dependent Protein Degradation Events in a Model Cyanobacterium. Mol Cell Proteomics 2021; 20:100162. [PMID: 34655801 PMCID: PMC8603205 DOI: 10.1016/j.mcpro.2021.100162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 09/08/2021] [Accepted: 10/11/2021] [Indexed: 11/06/2022] Open
Abstract
Light is essential for photosynthetic organisms and is involved in the regulation of protein synthesis and degradation. The significance of light-regulated protein degradation is exemplified by the well-established light-induced degradation and repair of the photosystem II reaction center D1 protein in higher plants and cyanobacteria. However, systematic studies of light-regulated protein degradation events in photosynthetic organisms are lacking. Thus, we conducted a large-scale survey of protein degradation under light or dark conditions in the model cyanobacterium Synechocystis sp. PCC 6803 (hereafter referred to as Synechocystis) using the isobaric labeling-based quantitative proteomics technique. The results revealed that 79 proteins showed light-regulated degradation, including proteins involved in photosystem II structure or function, quinone binding, and NADH dehydrogenase. Among these, 25 proteins were strongly dependent on light for degradation. Moreover, the light-dependent degradation of several proteins was sensitive to photosynthetic electron transport inhibitors (DCMU and DBMIB), suggesting that they are influenced by the redox state of the plastoquinone (PQ) pool. Together, our study comprehensively cataloged light-regulated protein degradation events, and the results serve as an important resource for future studies aimed at understanding light-regulated processes and protein quality control mechanisms in cyanobacteria. Light-/dark-regulated protein degradation events in a model Cyanobacterium were identified. Seventy-nine proteins displayed light-regulated degradation. Thirty-one proteins displayed dark-regulated degradation. Multiple light-regulated protein degradation events were regulated by the redox state of the plastoquinone pool.
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Affiliation(s)
- Weiyang Chen
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Limin Zheng
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Jinghui Dong
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Haitao Ge
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Xiahe Huang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Gaojie Wang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Chengcheng Huang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yan Wang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Dandan Lu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Wu Xu
- Department of Chemistry, University of Louisiana at Lafayette, Lafayette, Louisiana, USA
| | - Yingchun Wang
- State Key Laboratory of Molecular Developmental Biology, Innovation Academy for Seed Design, CAS, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China.
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7
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Rredhi A, Petersen J, Schubert M, Li W, Oldemeyer S, Li W, Westermann M, Wagner V, Kottke T, Mittag M. DASH cryptochrome 1, a UV-A receptor, balances the photosynthetic machinery of Chlamydomonas reinhardtii. THE NEW PHYTOLOGIST 2021; 232:610-624. [PMID: 34235760 DOI: 10.1111/nph.17603] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
Drosophila, Arabidopsis, Synechocystis, Homo (DASH) cryptochromes belong to the cryptochrome/photolyase family and can act as DNA repair enzymes. In bacteria and fungi, they also can play regulatory roles, but in plants their biological functions remain elusive. Here, we characterize CRY-DASH1 from the green alga Chlamydomonas reinhardtii. We perform biochemical and in vitro photochemical analysis. For functional characterization, a knock-out mutant of cry-dash1 is used. CRY-DASH1 protein is localized in the chloroplast and accumulates at midday. Although the photoautotrophic growth of the mutant is significantly reduced compared to the wild-type (WT), the mutant has increased levels of photosynthetic pigments and a higher maximum photochemical efficiency of photosystem II (PS II). Hyper-stacking of thylakoid membranes occurs together with an increase in proteins of the PS II reaction center, D1 and its antenna CP43, but not of their transcripts. CRY-DASH1 binds fully reduced flavin adenine dinucleotide and the antenna 5,10-methenyltetrahydrofolate, leading to an absorption peak in the UV-A range. Supplementation of white light with UV-A increases photoautotrophic growth of the WT but not of the cry-dash1 mutant. These results suggest a balancing function of CRY-DASH1 in the photosynthetic machinery and point to its role as a photoreceptor for the UV-A range separated from the absorption of photosynthetic pigments.
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Affiliation(s)
- Anxhela Rredhi
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
| | - Jan Petersen
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
| | - Melvin Schubert
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
| | - Wei Li
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
| | - Sabine Oldemeyer
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Bielefeld, 33615, Germany
| | - Wenshuang Li
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
| | - Martin Westermann
- Electron Microscopy Center, Jena University Hospital, Jena, 07743, Germany
| | - Volker Wagner
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
| | - Tilman Kottke
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Bielefeld, 33615, Germany
- Medical School OWL, Bielefeld University, Bielefeld, 33615, Germany
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University Jena, Jena, 07743, Germany
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8
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Diel transcriptional oscillations of light-sensitive regulatory elements in open-ocean eukaryotic plankton communities. Proc Natl Acad Sci U S A 2021; 118:2011038118. [PMID: 33547239 PMCID: PMC8017926 DOI: 10.1073/pnas.2011038118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Most organisms coordinate key biological events to coincide with the day/night cycle. These diel oscillations are entrained through the activity of light-sensitive photoreceptors that allow organisms to respond rapidly to changes in light exposure. In the ocean, the plankton community must additionally contend with dramatic changes in the quantity and quality of light over depth. Here, we show that the predominantly blue-light field in the open-ocean environment may have driven expansion of blue light-sensitive regulatory elements in open-ocean eukaryotic plankton derived from secondary and tertiary endosymbiosis. The diel transcription of genes encoding light-sensitive elements indicate that photosynthetic and heterotrophic marine protists respond to and anticipate fluctuating light conditions in the dynamic marine environment. The 24-h cycle of light and darkness governs daily rhythms of complex behaviors across all domains of life. Intracellular photoreceptors sense specific wavelengths of light that can reset the internal circadian clock and/or elicit distinct phenotypic responses. In the surface ocean, microbial communities additionally modulate nonrhythmic changes in light quality and quantity as they are mixed to different depths. Here, we show that eukaryotic plankton in the North Pacific Subtropical Gyre transcribe genes encoding light-sensitive proteins that may serve as light-activated transcription factors, elicit light-driven electrical/chemical cascades, or initiate secondary messenger-signaling cascades. Overall, the protistan community relies on blue light-sensitive photoreceptors of the cryptochrome/photolyase family, and proteins containing the Light-Oxygen-Voltage (LOV) domain. The greatest diversification occurred within Haptophyta and photosynthetic stramenopiles where the LOV domain was combined with different DNA-binding domains and secondary signal-transduction motifs. Flagellated protists utilize green-light sensory rhodopsins and blue-light helmchromes, potentially underlying phototactic/photophobic and other behaviors toward specific wavelengths of light. Photoreceptors such as phytochromes appear to play minor roles in the North Pacific Subtropical Gyre. Transcript abundance of environmental light-sensitive protein-encoding genes that display diel patterns are found to primarily peak at dawn. The exceptions are the LOV-domain transcription factors with peaks in transcript abundances at different times and putative phototaxis photoreceptors transcribed throughout the day. Together, these data illustrate the diversity of light-sensitive proteins that may allow disparate groups of protists to respond to light and potentially synchronize patterns of growth, division, and mortality within the dynamic ocean environment.
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Goett-Zink L, Toschke AL, Petersen J, Mittag M, Kottke T. C-Terminal Extension of a Plant Cryptochrome Dissociates from the β-Sheet of the Flavin-Binding Domain. J Phys Chem Lett 2021; 12:5558-5563. [PMID: 34101477 DOI: 10.1021/acs.jpclett.1c00844] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Plant cryptochromes are central blue light receptors in land plants and algae. Photoreduction of the flavin bound to the photolyase homology region (PHR) causes a dissociation of the C-terminal extension (CCT) as effector via an unclear pathway. We applied the recently developed in-cell infrared difference (ICIRD) spectroscopy to study the response of the full-length pCRY from Chlamydomonas reinhardtii in living bacterial cells, because the receptor degraded upon isolation. We demonstrate a stabilization of the flavin neutral radical as photoproduct and of the resulting β-sheet reorganization by binding of cellular ATP. Comparison between light-induced structural responses of full-length pCRY and PHR reveals a downshift in frequency of the β-sheet signal, implying an association of the CCT close to the only β-sheet of the PHR in the dark. We provide a missing link in activation of plant cryptochromes after flavin photoreduction by indicating that β-sheet reorganization causes the CCT release and restructuring.
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Affiliation(s)
- Lukas Goett-Zink
- Physical and Biophysical Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Anna Lena Toschke
- Physical and Biophysical Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Jan Petersen
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, 07743 Jena, Germany
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, 07743 Jena, Germany
| | - Tilman Kottke
- Physical and Biophysical Chemistry, Bielefeld University, 33615 Bielefeld, Germany
- Medical School OWL, Bielefeld University, 33615 Bielefeld, Germany
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10
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Tao M, Xiao K, Zheng Y, Li Z, Luo Q, Wang G, Hu Z. Identification and characterization of a novel Channelrhodopsin gene HpChR1 in Haematococcus pluvialis. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Biswal DP, Panigrahi KCS. Light- and hormone-mediated development in non-flowering plants: An overview. PLANTA 2020; 253:1. [PMID: 33245411 DOI: 10.1007/s00425-020-03501-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 10/21/2020] [Indexed: 06/11/2023]
Abstract
Light, hormones and their interaction regulate different aspects of development in non-flowering plants. They might have played a role in the evolution of different plant groups by conferring specific adaptive evolutionary changes. Plants are sessile organisms. Unlike animals, they lack the opportunity to abandon their habitat in unfavorable conditions. They respond to different environmental cues and adapt accordingly to control their growth and developmental pattern. While phytohormones are known to be internal regulators of plant development, light is a major environmental signal that shapes plant processes. It is plausible that light-hormone crosstalk might have played an important role in plant evolution. But how the crosstalk between light and phytohormone signaling pathways might have shaped the plant evolution is unclear. One of the possible reasons is that flowering plants have been studied extensively in context of plant development, which cannot serve the purpose of evolutionary comparisons. In order to elucidate the role of light, hormone and their crosstalk in the evolutionary adaptation in plant kingdom, one needs to understand various light- and hormone-mediated processes in diverse non-flowering plants. This review is an attempt to outline major light- and phytohormone-mediated responses in non-flowering plant groups such as algae, bryophytes, pteridophytes and gymnosperms.
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Affiliation(s)
- Durga Prasad Biswal
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha, India
- Homi Bhabha National Institute (HBNI), Training School Complex, Anushakti Nagar, Mumbai, 400094, India
| | - Kishore Chandra Sekhar Panigrahi
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha, India.
- Homi Bhabha National Institute (HBNI), Training School Complex, Anushakti Nagar, Mumbai, 400094, India.
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12
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Abstract
Cryptochromes are blue-light receptors that mediate photoresponses in plants. The genomes of most land plants encode two clades of cryptochromes, CRY1 and CRY2, which mediate distinct and overlapping photoresponses within the same species and between different plant species. Photoresponsive protein-protein interaction is the primary mode of signal transduction of cryptochromes. Cryptochromes exist as physiologically inactive monomers in the dark; the absorption of photons leads to conformational change and cryptochrome homooligomerization, which alters the affinity of cryptochromes interacting with cryptochrome-interacting proteins to form various cryptochrome complexes. These cryptochrome complexes, collectively referred to as the cryptochrome complexome, regulate transcription or stability of photoresponsive proteins to modulate plant growth and development. The activity of cryptochromes is regulated by photooligomerization; dark monomerization; cryptochrome regulatory proteins; and cryptochrome phosphorylation, ubiquitination, and degradation. Most of the more than 30 presently known cryptochrome-interacting proteins are either regulated by other photoreceptors or physically interactingwith the protein complexes of other photoreceptors. Some cryptochrome-interacting proteins are also hormonal signaling or regulatory proteins. These two mechanisms enable cryptochromes to integrate blue-light signals with other internal and external signals to optimize plant growth and development.
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Affiliation(s)
- Qin Wang
- Basic Forestry and Proteomics Research Center, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Chentao Lin
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095, USA;
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13
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Cloning, expression, and characterization of a novel plant type cryptochrome gene from the green alga Haematococcus pluvialis. Protein Expr Purif 2020; 172:105633. [PMID: 32259580 DOI: 10.1016/j.pep.2020.105633] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/30/2020] [Indexed: 11/20/2022]
Abstract
A full-length cDNA sequence of plant type CRY (designated Hae-P-CRY) was cloned from the green alga Haematococcus pluvialis. The cDNA sequence was 3608 base pairs (bp) in length, which contained a 2988-bp open reading frame encoding 995 amino acids with molecular mass of 107.7 kDa and isoelectric point of 6.19. Multiple alignment analysis revealed that the deduced amino acid sequence of Hae-P-CRY shared high identity of 47-66% with corresponding plant type CRYs from other eukaryotes. The catalytic motifs of plant type CRYs were detected in the amino acid sequence of Hae-P-CRY including the typical PHR and CTE domains. Phylogenetic analysis showed that the Hae-P-CRY was grouped together with other plant type CRYs from green algae and higher plants, which distinguished from other distinct groups. The transcriptional level of Hae-P-CRY was strongly decreased after 0-4 h under HL stress. In addition, the Hae-P-CRY gene was heterologously expressed in Escherichia coli BL21 (DE3) and successfully purified. The typical spectroscopic characteristics of plant type CRYs were present in Hae-P-CRY indicated that it may be an active enzyme, which provided valuable clue for further functional investigation in the green alga H. pluvialis. These results lay the foundation for further function and interaction protein identification involved in CRYs mediated signal pathway under HL stress in H. pluvialis.
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14
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Xu L, Wen B, Shao W, Yao P, Zheng W, Zhou Z, Zhang Y, Zhu G. Impacts of Cys392, Asp393, and ATP on the FAD Binding, Photoreduction, and the Stability of the Radical State of Chlamydomonas reinhardtii Cryptochrome. Chembiochem 2019; 20:940-948. [PMID: 30548754 DOI: 10.1002/cbic.201800660] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Indexed: 12/16/2022]
Abstract
Plant cryptochromes (CRYs) are blue-light receptors that regulate light-dependent growth, development, and circadian rhythms. A flavin adenine dinucleotide (FAD) cofactor is bound to the photolyase homology region (PHR) of plant CRYs and can be photoreduced to a neutral radical state under blue light. This photoreaction can trigger subsequent signal transduction. Plant CRYs can also bind an ATP molecule adjacent to FAD in a pocket of the PHR. Chlamydomonas reinhardtii contains a single plant CRY, named Chlamydomonas photolyase homologue 1 (CPH1). In CPH1, Cys392 and Asp393 are located near the FAD cofactor. Here we have shown that replacing Cys392 with Ser has little effect on the properties of CPH1. The C392N mutant, however, showed a faster photoreduction rate than wild-type CPH1, together with a significantly lower oxidation rate of the neutral radical state. Substituting an Asn residue for Asp393 in CPH1 improved the binding affinity for FAD as well as the stability of the neutral radical, but photoreduction in the case of this mutant was severely inhibited. In the presence of ATP, CPH1 and its mutants exhibited significantly higher binding affinity for FAD and slower oxidation of the neutral radical. These results reveal that the residues at site 392 and the presence of ATP can tune the stability of the neutral radical, that the Asp residue at site 393 is crucial for photoreduction, and that the photoreduction rate is not determined merely by the stability of the neutral radical in CPH1.
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Affiliation(s)
- Lei Xu
- Anhui Province Key Laboratory of Active Biological Macromolecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, P. R. China
| | - Bin Wen
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, P. R. China
| | - Wengui Shao
- Anhui Province Key Laboratory of Active Biological Macromolecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, P. R. China
| | - Pengcheng Yao
- Anhui Province Key Laboratory of Active Biological Macromolecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, P. R. China
| | - Wei Zheng
- Anhui Province Key Laboratory of Active Biological Macromolecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, P. R. China
| | - Zhiqiang Zhou
- Anhui Province Key Laboratory of Active Biological Macromolecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, P. R. China
| | - Yao Zhang
- Anhui Province Key Laboratory of Active Biological Macromolecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, P. R. China
| | - Guoping Zhu
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, P. R. China
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15
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Kamrani YY, Matsuo T, Mittag M, Minagawa J. ROC75 is an Attenuator for the Circadian Clock that Controls LHCSR3 Expression. PLANT & CELL PHYSIOLOGY 2018; 59:2602-2607. [PMID: 30184184 DOI: 10.1093/pcp/pcy179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
Strong light intensity leads to harmful overexcitation of the photosystems in green algae. In Chlamydomonas reinhardtii, LHCSR3 is required for the rapid protective response known as energy-dependent quenching (qE). Because the majority of photoacclimation analysis has been conducted under controlled laboratory conditions, physiological responses to natural environmental changes such as light/dark cycles have not been examined in detail. Regarding fitness in higher plants and microalgae, light-dark cycles represent a major Zeitgeber for synchronizing the circadian clock to multiple physiological responses, yet there is little consensus with respect to the clock response to high-intensity light in photosynthetic organisms. In a previous study, 105 circadian rhythm insertional mutants were isolated as rhythm of chloroplast (roc) mutants. Here, we report our characterization of the roc75 mutant, which exhibited a significantly higher qE value and LHCSR3 protein accumulation when grown under red light. We performed transcript analysis of ROC75 in the pcry (plant-cryptochrome) and phot mutants and found that only the former accumulated lower levels of ROC75 mRNA, suggesting that the blue light photoreceptor pCRY positively regulates ROC75. However, the degradation of pCRY by high-light exposure contributes to prevent over-accumulation of ROC75, which in turn facilitates the PHOT mediated main activation pathway for LHCSR3. Furthermore, LHCSR3 mRNA exhibited a circadian rhythm, though its basal expression level in the roc75 mutant was higher than that in WT. We therefore conclude that ROC75 acts as an attenuator of the circadian clock to control LHCSR3 expression with blue and red light as stimuli for attenuation.
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Affiliation(s)
- Yousef Yari Kamrani
- Division of Environmental Photobiology, National Institute for Basic Biology, Okazaki, Aichi, Japan
- Department of Basic Biology, School of Life Science, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
| | - Takuya Matsuo
- Center for Gene Research, Nagoya University, Nagoya, Aichi, Japan
| | - Maria Mittag
- Matthias Schleiden Institute of Genetics, Bioinformatics and Molecular Botany, Friedrich Schiller University, Jena, Germany
| | - Jun Minagawa
- Division of Environmental Photobiology, National Institute for Basic Biology, Okazaki, Aichi, Japan
- Department of Basic Biology, School of Life Science, Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
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16
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Couso I, Pérez-Pérez ME, Martínez-Force E, Kim HS, He Y, Umen JG, Crespo JL. Autophagic flux is required for the synthesis of triacylglycerols and ribosomal protein turnover in Chlamydomonas. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1355-1367. [PMID: 29053817 PMCID: PMC6018900 DOI: 10.1093/jxb/erx372] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 09/28/2017] [Indexed: 05/19/2023]
Abstract
Autophagy is an intracellular catabolic process that allows cells to recycle unneeded or damaged material to maintain cellular homeostasis. This highly dynamic process is characterized by the formation of double-membrane vesicles called autophagosomes, which engulf and deliver the cargo to the vacuole. Flow of material through the autophagy pathway and its degradation in the vacuole is known as autophagic flux, and reflects the autophagic degradation activity. A number of assays have been developed to determine autophagic flux in yeasts, mammals, and plants, but it has not been examined yet in algae. Here we analyzed autophagic flux in the model green alga Chlamydomonas reinhardtii. By monitoring specific autophagy markers such as ATG8 lipidation and using immunofluorescence and electron microscopy techniques, we show that concanamycin A, a vacuolar ATPase inhibitor, blocks autophagic flux in Chlamydomonas. Our results revealed that vacuolar lytic function is needed for the synthesis of triacylglycerols and the formation of lipid bodies in nitrogen- or phosphate-starved cells. Moreover, we found that concanamycin A treatment prevented the degradation of ribosomal proteins RPS6 and RPL37 under nitrogen or phosphate deprivation. These results indicate that autophagy might play an important role in the regulation of lipid metabolism and the recycling of ribosomal proteins under nutrient limitation in Chlamydomonas.
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Affiliation(s)
- Inmaculada Couso
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad de Sevilla, Seville, Spain
| | - María Esther Pérez-Pérez
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad de Sevilla, Seville, Spain
| | - Enrique Martínez-Force
- Instituto de la Grasa (CSIC), Edificio 46, Campus Universitario Pablo de Olavide, Seville, Spain
| | - Hee-Sik Kim
- Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Korea
| | - Yonghua He
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - James G Umen
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - José L Crespo
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad de Sevilla, Seville, Spain
- Correspondence:
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17
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Schroeder L, Oldemeyer S, Kottke T. Time-Resolved Infrared Spectroscopy on Plant Cryptochrome—Relevance of Proton Transfer and ATP Binding for Signaling. J Phys Chem A 2017; 122:140-147. [DOI: 10.1021/acs.jpca.7b10249] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lea Schroeder
- Physical and Biophysical
Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße
25, 33615 Bielefeld, Germany
| | - Sabine Oldemeyer
- Physical and Biophysical
Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße
25, 33615 Bielefeld, Germany
| | - Tilman Kottke
- Physical and Biophysical
Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße
25, 33615 Bielefeld, Germany
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18
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Duanmu D, Rockwell NC, Lagarias JC. Algal light sensing and photoacclimation in aquatic environments. PLANT, CELL & ENVIRONMENT 2017; 40:2558-2570. [PMID: 28245058 PMCID: PMC5705019 DOI: 10.1111/pce.12943] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 02/13/2017] [Accepted: 02/15/2017] [Indexed: 05/05/2023]
Abstract
Anoxygenic photosynthetic prokaryotes arose in ancient oceans ~3.5 billion years ago. The evolution of oxygenic photosynthesis by cyanobacteria followed soon after, enabling eukaryogenesis and the evolution of complex life. The Archaeplastida lineage dates back ~1.5 billion years to the domestication of a cyanobacterium. Eukaryotic algae have subsequently radiated throughout oceanic/freshwater/terrestrial environments, adopting distinctive morphological and developmental strategies for adaptation to diverse light environments. Descendants of the ancestral photosynthetic alga remain challenged by a typical diurnally fluctuating light supply ranging from ~0 to ~2000 μE m-2 s-1 . Such extreme changes in light intensity and variations in light quality have driven the evolution of novel photoreceptors, light-harvesting complexes and photoprotective mechanisms in photosynthetic eukaryotes. This minireview focuses on algal light sensors, highlighting the unexpected roles for linear tetrapyrroles (bilins) in the maintenance of functional chloroplasts in chlorophytes, sister species to streptophyte algae and land plants.
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Affiliation(s)
- Deqiang Duanmu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
- Corresponding authors: Deqiang Duanmu, State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China. Tel:+86-27-87282101; Fax:+86-27-87282469; ; J. Clark Lagarias, Department of Molecular and Cellular Biology, University of California, Davis CA 95616. Tel: 530-752-1865; Fax: 530-752-3085;
| | - Nathan C. Rockwell
- Department of Molecular and Cellular Biology, University of California, Davis CA 95616
| | - J. Clark Lagarias
- Department of Molecular and Cellular Biology, University of California, Davis CA 95616
- Corresponding authors: Deqiang Duanmu, State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China. Tel:+86-27-87282101; Fax:+86-27-87282469; ; J. Clark Lagarias, Department of Molecular and Cellular Biology, University of California, Davis CA 95616. Tel: 530-752-1865; Fax: 530-752-3085;
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19
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Essen LO, Franz S, Banerjee A. Structural and evolutionary aspects of algal blue light receptors of the cryptochrome and aureochrome type. JOURNAL OF PLANT PHYSIOLOGY 2017; 217:27-37. [PMID: 28756992 DOI: 10.1016/j.jplph.2017.07.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Revised: 07/05/2017] [Accepted: 07/05/2017] [Indexed: 06/07/2023]
Abstract
Blue-light reception plays a pivotal role for algae to adapt to changing environmental conditions. In this review we summarize the current structural and mechanistic knowledge about flavin-dependent algal photoreceptors. We especially focus on the cryptochrome and aureochrome type photoreceptors in the context of their evolutionary divergence. Despite similar photochemical characteristics to orthologous photoreceptors from higher plants and animals the algal blue-light photoreceptors have developed a set of unique structural and mechanistic features that are summarized below.
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Affiliation(s)
- Lars-Oliver Essen
- Department of Biochemistry, Philipps-University, 35043 Marburg, Germany; LOEWE Center for Synthetic Microbiology, Philipps-University, 35043 Marburg, Germany.
| | - Sophie Franz
- Department of Biochemistry, Philipps-University, 35043 Marburg, Germany
| | - Ankan Banerjee
- Department of Biochemistry, Philipps-University, 35043 Marburg, Germany
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20
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Kottke T, Oldemeyer S, Wenzel S, Zou Y, Mittag M. Cryptochrome photoreceptors in green algae: Unexpected versatility of mechanisms and functions. JOURNAL OF PLANT PHYSIOLOGY 2017; 217:4-14. [PMID: 28619534 DOI: 10.1016/j.jplph.2017.05.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 05/29/2017] [Accepted: 05/29/2017] [Indexed: 06/07/2023]
Abstract
Green algae have a highly complex and diverse set of cryptochrome photoreceptor candidates including members of the following subfamilies: plant, plant-like, animal-like, DASH and cryptochrome photolyase family 1 (CPF1). While some green algae encode most or all of them, others lack certain members. Here we present an overview about functional analyses of so far investigated cryptochrome photoreceptors from the green algae Chlamydomonas reinhardtii (plant and animal-like cryptochromes) and Ostreococcus tauri (CPF1) with regard to their biological significance and spectroscopic properties. Cryptochromes of both algae have been demonstrated recently to be involved to various extents in circadian clock regulation and in Chlamydomonas additionally in life cycle control. Moreover, CPF1 even performs light-driven DNA repair. The plant cryptochrome and CPF1 are UVA/blue light receptors, whereas the animal-like cryptochrome responds to almost the whole visible spectrum including red light. Accordingly, plant cryptochrome, animal-like cryptochrome and CPF1 differ fundamentally in their structural response to light as revealed by their visible and infrared spectroscopic signatures, and in the role of the flavin neutral radical acting as dark form or signaling state.
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Affiliation(s)
- Tilman Kottke
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Sabine Oldemeyer
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Sandra Wenzel
- Institute of General Botany and Plant Physiology, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Yong Zou
- Institute of General Botany and Plant Physiology, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Maria Mittag
- Institute of General Botany and Plant Physiology, Friedrich Schiller University Jena, 07743 Jena, Germany.
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21
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Zou Y, Wenzel S, Müller N, Prager K, Jung EM, Kothe E, Kottke T, Mittag M. An Animal-Like Cryptochrome Controls the Chlamydomonas Sexual Cycle. PLANT PHYSIOLOGY 2017; 174:1334-1347. [PMID: 28468769 PMCID: PMC5490917 DOI: 10.1104/pp.17.00493] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 04/28/2017] [Indexed: 05/26/2023]
Abstract
Cryptochromes are known as flavin-binding blue light receptors in bacteria, fungi, plants, and insects. The animal-like cryptochrome (aCRY) of the green alga Chlamydomonas reinhardtii has extended our view on cryptochromes, because it responds also to other wavelengths of the visible spectrum, including red light. Here, we have investigated if aCRY is involved in the regulation of the sexual life cycle of C. reinhardtii, which is controlled by blue and red light at the steps of gametogenesis along with its restoration and germination. We show that aCRY is differentially expressed not only during the life cycle but also within the cell as part of the soluble and/or membrane-associated protein fraction. Moreover, localization of aCRY within the algal cell body varies between vegetative cells and the different cell types of gametogenesis. aCRY is significantly (early day) or to a small extent (late night) enriched in the nucleus in vegetative cells. In pregametes, gametes and dark-inactivated gametes, aCRY is localized over the cell body. aCRY plays an important role in the sexual life cycle of C. reinhardtii: It controls the germination of the alga, under which the zygote undergoes meiosis, in a positive manner, similar to the regulation by the blue light receptors phototropin and plant cryptochrome (pCRY). However, aCRY acts in combination with pCRY as a negative regulator for mating ability as well as for mating maintenance, opposite to the function of phototropin in these processes.
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Affiliation(s)
- Yong Zou
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Sandra Wenzel
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Nico Müller
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Katja Prager
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Elke-Martina Jung
- Institute of Microbiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Erika Kothe
- Institute of Microbiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Tilman Kottke
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Maria Mittag
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
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22
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Xu L, Wen B, Wang Y, Tian C, Wu M, Zhu G. Residues at a Single Site Differentiate Animal Cryptochromes from Cyclobutane Pyrimidine Dimer Photolyases by Affecting the Proteins' Preferences for Reduced FAD. Chembiochem 2017; 18:1129-1137. [PMID: 28393477 DOI: 10.1002/cbic.201700145] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Indexed: 12/29/2022]
Abstract
Cryptochromes (CRYs) and photolyases belong to the cryptochrome/photolyase family (CPF). Reduced FAD is essential for photolyases to photorepair UV-induced cyclobutane pyrimidine dimers (CPDs) or 6-4 photoproducts in DNA. In Drosophila CRY (dCRY, a type I animal CRY), FAD is converted to the anionic radical but not to the reduced state upon illumination, which might induce a conformational change in the protein to relay the light signal downstream. To explore the foundation of these differences, multiple sequence alignment of 650 CPF protein sequences was performed. We identified a site facing FAD (Ala377 in Escherichia coli CPD photolyase and Val415 in dCRY), hereafter referred to as "site 377", that was distinctly conserved across these sequences: CPD photolyases often had Ala, Ser, or Asn at this site, whereas animal CRYs had Ile, Leu, or Val. The binding affinity for reduced FAD, but not the photorepair activity of E. coli photolyase, was dramatically impaired when replacing Ala377 with any of the three CRY residues. Conversely, in V415S and V415N mutants of dCRY, FAD was photoreduced to its fully reduced state after prolonged illumination, and light-dependent conformational changes of these mutants were severely inhibited. We speculate that the residues at site 377 play a key role in the different preferences of CPF proteins for reduced FAD, which differentiate animal CRYs from CPD photolyases.
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Affiliation(s)
- Lei Xu
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, China.,Anhui Province Key Laboratory of Active Biological Macro-Molecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, China
| | - Bin Wen
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, China.,Anhui Province Key Laboratory of Active Biological Macro-Molecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, China
| | - Yuan Wang
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, China
| | - Changqing Tian
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, China
| | - Mingcai Wu
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, China.,Anhui Province Key Laboratory of Active Biological Macro-Molecules, Wannan Medical College, 22# Wenchang West Road, Wuhu, 241002, Anhui, China
| | - Guoping Zhu
- Institute of Molecular Biology and Biotechnology, Anhui Normal University, 1# Beijing East Road, Wuhu, 241000, Anhui, China
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23
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Müller N, Wenzel S, Zou Y, Künzel S, Sasso S, Weiß D, Prager K, Grossman A, Kottke T, Mittag M. A Plant Cryptochrome Controls Key Features of the Chlamydomonas Circadian Clock and Its Life Cycle. PLANT PHYSIOLOGY 2017; 174:185-201. [PMID: 28360233 PMCID: PMC5411161 DOI: 10.1104/pp.17.00349] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 03/28/2017] [Indexed: 05/25/2023]
Abstract
Cryptochromes are flavin-binding proteins that act as blue light receptors in bacteria, fungi, plants, and insects and are components of the circadian oscillator in mammals. Animal and plant cryptochromes are evolutionarily divergent, although the unicellular alga Chlamydomonas reinhardtii (Chlamydomonas throughout) has both an animal-like cryptochrome and a plant cryptochrome (pCRY; formerly designated CPH1). Here, we show that the pCRY protein accumulates at night as part of a complex. Functional characterization of pCRY was performed based on an insertional mutant that expresses only 11% of the wild-type pCRY level. The pcry mutant is defective for central properties of the circadian clock. In the mutant, the period is lengthened significantly, ultimately resulting in arrhythmicity, while blue light-based phase shifts show large deviations from what is observed in wild-type cells. We also show that pCRY is involved in gametogenesis in Chlamydomonas pCRY is down-regulated in pregametes and gametes, and in the pcry mutant, there is altered transcript accumulation under blue light of the strictly light-dependent, gamete-specific gene GAS28 pCRY acts as a negative regulator for the induction of mating ability in the light and for the loss of mating ability in the dark. Moreover, pCRY is necessary for light-dependent germination, during which the zygote undergoes meiosis that gives rise to four vegetative cells. In sum, our data demonstrate that pCRY is a key blue light receptor in Chlamydomonas that is involved in both circadian timing and life cycle progression.
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Affiliation(s)
- Nico Müller
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Sandra Wenzel
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Yong Zou
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Sandra Künzel
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Severin Sasso
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Daniel Weiß
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Katja Prager
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Arthur Grossman
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Tilman Kottke
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.)
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.)
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
| | - Maria Mittag
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany (N.M., S.W., Y.Z., S.K., S.S., D.W., K.P., M.M.);
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (A.G.);
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany (T.K.); and
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany (S.S.)
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Kinoshita A, Niwa Y, Onai K, Yamano T, Fukuzawa H, Ishiura M, Matsuo T. CSL encodes a leucine-rich-repeat protein implicated in red/violet light signaling to the circadian clock in Chlamydomonas. PLoS Genet 2017; 13:e1006645. [PMID: 28333924 PMCID: PMC5363811 DOI: 10.1371/journal.pgen.1006645] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 02/20/2017] [Indexed: 01/12/2023] Open
Abstract
The green alga Chlamydomonas reinhardtii shows various light responses in behavior and physiology. One such photoresponse is the circadian clock, which can be reset by external light signals to entrain its oscillation to daily environmental cycles. In a previous report, we suggested that a light-induced degradation of the clock protein ROC15 is a trigger to reset the circadian clock in Chlamydomonas. However, light signaling pathways of this process remained unclear. Here, we screened for mutants that show abnormal ROC15 diurnal rhythms, including the light-induced protein degradation at dawn, using a luciferase fusion reporter. In one mutant, ROC15 degradation and phase resetting of the circadian clock by light were impaired. Interestingly, the impairments were observed in response to red and violet light, but not to blue light. We revealed that an uncharacterized gene encoding a protein similar to RAS-signaling-related leucine-rich repeat (LRR) proteins is responsible for the mutant phenotypes. Our results indicate that a previously uncharacterized red/violet light signaling pathway is involved in the phase resetting of circadian clock in Chlamydomonas. The unicellular green alga Chlamydomonas reinhardtii is used as a model system in many biological researches. Although blue light responses of this alga (e.g., phototaxis) are well known and well characterized, far less is understood about responses to other wavelengths. One such photoresponse is the circadian clock, which can be reset by various wavelengths of light, ranging from violet to red, to entrain its oscillation to daily environmental cycles. In this study, we identified a gene responsible for red and violet light responses of the circadian clock by a forward genetic screen. Our results shed light on a previously unrecognized red/violet light signaling pathway in green algae.
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Affiliation(s)
- Ayumi Kinoshita
- Center for Gene Research, Nagoya University, Nagoya, Japan
- Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Yoshimi Niwa
- Center for Gene Research, Nagoya University, Nagoya, Japan
- Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Kiyoshi Onai
- Center for Gene Research, Nagoya University, Nagoya, Japan
| | - Takashi Yamano
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Hideya Fukuzawa
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Masahiro Ishiura
- Center for Gene Research, Nagoya University, Nagoya, Japan
- Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Takuya Matsuo
- Center for Gene Research, Nagoya University, Nagoya, Japan
- Graduate School of Science, Nagoya University, Nagoya, Japan
- * E-mail:
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Tardu M, Dikbas UM, Baris I, Kavakli IH. RNA-seq analysis of the transcriptional response to blue and red light in the extremophilic red alga, Cyanidioschyzon merolae. Funct Integr Genomics 2016; 16:657-669. [DOI: 10.1007/s10142-016-0521-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Revised: 08/22/2016] [Accepted: 08/30/2016] [Indexed: 10/21/2022]
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Tilbrook K, Dubois M, Crocco CD, Yin R, Chappuis R, Allorent G, Schmid-Siegert E, Goldschmidt-Clermont M, Ulm R. UV-B Perception and Acclimation in Chlamydomonas reinhardtii. THE PLANT CELL 2016; 28:966-83. [PMID: 27020958 PMCID: PMC4863380 DOI: 10.1105/tpc.15.00287] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 03/25/2016] [Indexed: 05/03/2023]
Abstract
Plants perceive UV-B, an intrinsic component of sunlight, via a signaling pathway that is mediated by the photoreceptor UV RESISTANCE LOCUS8 (UVR8) and induces UV-B acclimation. To test whether similar UV-B perception mechanisms exist in the evolutionarily distant green alga Chlamydomonas reinhardtii, we identified Chlamydomonas orthologs of UVR8 and the key signaling factor CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1). Cr-UVR8 shares sequence and structural similarity to Arabidopsis thaliana UVR8, has conserved tryptophan residues for UV-B photoreception, monomerizes upon UV-B exposure, and interacts with Cr-COP1 in a UV-B-dependent manner. Moreover, Cr-UVR8 can interact with At-COP1 and complement the Arabidopsis uvr8 mutant, demonstrating that it is a functional UV-B photoreceptor. Chlamydomonas shows apparent UV-B acclimation in colony survival and photosynthetic efficiency assays. UV-B exposure, at low levels that induce acclimation, led to broad changes in the Chlamydomonas transcriptome, including in genes related to photosynthesis. Impaired UV-B-induced activation in the Cr-COP1 mutant hit1 indicates that UVR8-COP1 signaling induces transcriptome changes in response to UV-B. Also, hit1 mutants are impaired in UV-B acclimation. Chlamydomonas UV-B acclimation preserved the photosystem II core proteins D1 and D2 under UV-B stress, which mitigated UV-B-induced photoinhibition. These findings highlight the early evolution of UVR8 photoreceptor signaling in the green lineage to induce UV-B acclimation and protection.
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Affiliation(s)
- Kimberley Tilbrook
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland
| | - Marine Dubois
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland
| | - Carlos D Crocco
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland
| | - Ruohe Yin
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland
| | - Richard Chappuis
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland
| | - Guillaume Allorent
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland
| | - Emanuel Schmid-Siegert
- SIB-Swiss Institute of Bioinformatics, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Michel Goldschmidt-Clermont
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, CH-1211 Geneva 4, Switzerland
| | - Roman Ulm
- Department of Botany and Plant Biology, University of Geneva, Sciences III, CH-1211 Geneva 4, Switzerland Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, CH-1211 Geneva 4, Switzerland
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Romero-Campero FJ, Perez-Hurtado I, Lucas-Reina E, Romero JM, Valverde F. ChlamyNET: a Chlamydomonas gene co-expression network reveals global properties of the transcriptome and the early setup of key co-expression patterns in the green lineage. BMC Genomics 2016; 17:227. [PMID: 26968660 PMCID: PMC4788957 DOI: 10.1186/s12864-016-2564-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 03/02/2016] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Chlamydomonas reinhardtii is the model organism that serves as a reference for studies in algal genomics and physiology. It is of special interest in the study of the evolution of regulatory pathways from algae to higher plants. Additionally, it has recently gained attention as a potential source for bio-fuel and bio-hydrogen production. The genome of Chlamydomonas is available, facilitating the analysis of its transcriptome by RNA-seq data. This has produced a massive amount of data that remains fragmented making necessary the application of integrative approaches based on molecular systems biology. RESULTS We constructed a gene co-expression network based on RNA-seq data and developed a web-based tool, ChlamyNET, for the exploration of the Chlamydomonas transcriptome. ChlamyNET exhibits a scale-free and small world topology. Applying clustering techniques, we identified nine gene clusters that capture the structure of the transcriptome under the analyzed conditions. One of the most central clusters was shown to be involved in carbon/nitrogen metabolism and signalling, whereas one of the most peripheral clusters was involved in DNA replication and cell cycle regulation. The transcription factors and regulators in the Chlamydomonas genome have been identified in ChlamyNET. The biological processes potentially regulated by them as well as their putative transcription factor binding sites were determined. The putative light regulated transcription factors and regulators in the Chlamydomonas genome were analyzed in order to provide a case study on the use of ChlamyNET. Finally, we used an independent data set to cross-validate the predictive power of ChlamyNET. CONCLUSIONS The topological properties of ChlamyNET suggest that the Chlamydomonas transcriptome posseses important characteristics related to error tolerance, vulnerability and information propagation. The central part of ChlamyNET constitutes the core of the transcriptome where most authoritative hub genes are located interconnecting key biological processes such as light response with carbon and nitrogen metabolism. Our study reveals that key elements in the regulation of carbon and nitrogen metabolism, light response and cell cycle identified in higher plants were already established in Chlamydomonas. These conserved elements are not only limited to transcription factors, regulators and their targets, but also include the cis-regulatory elements recognized by them.
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Affiliation(s)
- Francisco J. Romero-Campero
- />Departamento de Ciencias de la Computación e Inteligencia Artificial, Universidad de Sevilla, Reina Mercedes s/n, 41012 Sevilla, Spain
| | - Ignacio Perez-Hurtado
- />Departamento de Ciencias de la Computación e Inteligencia Artificial, Universidad de Sevilla, Reina Mercedes s/n, 41012 Sevilla, Spain
| | - Eva Lucas-Reina
- />Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Americo Vespucio 49, 41092 Sevilla, Spain
| | - Jose M. Romero
- />Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Americo Vespucio 49, 41092 Sevilla, Spain
| | - Federico Valverde
- />Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Americo Vespucio 49, 41092 Sevilla, Spain
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Ryo M, Matsuo T, Yamashino T, Ichinose M, Sugita M, Aoki S. Diversity of plant circadian clocks: Insights from studies of Chlamydomonas reinhardtii and Physcomitrella patens. PLANT SIGNALING & BEHAVIOR 2016; 11:e1116661. [PMID: 26645746 PMCID: PMC4871632 DOI: 10.1080/15592324.2015.1116661] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Arabidopsis thaliana has long been the model plant of choice for elucidating the mechanisms of the circadian clock. Recently, relevant results have accumulated in other species of green plant lineages, including green algae. This mini-review describes a comparison of the mechanism of the A. thaliana clock to those of the green alga Chlamydomonas reinhardtii and the moss Physcomitrella patens, focusing on commonalities and divergences of subsystems of the clock. The potential of such an approach from an evolutionary viewpoint is discussed.
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Affiliation(s)
- Masashi Ryo
- Graduate School of Information Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Takuya Matsuo
- Center for Gene Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Takafumi Yamashino
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Mizuho Ichinose
- Center for Gene Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
- Institute of Transformative Bio-Molecules, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Mamoru Sugita
- Center for Gene Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Setsuyuki Aoki
- Graduate School of Information Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
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29
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Wang J, Du X, Pan W, Wang X, Wu W. Photoactivation of the cryptochrome/photolyase superfamily. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2015. [DOI: 10.1016/j.jphotochemrev.2014.12.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Fortunato AE, Annunziata R, Jaubert M, Bouly JP, Falciatore A. Dealing with light: the widespread and multitasking cryptochrome/photolyase family in photosynthetic organisms. JOURNAL OF PLANT PHYSIOLOGY 2015; 172:42-54. [PMID: 25087009 DOI: 10.1016/j.jplph.2014.06.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 06/17/2014] [Accepted: 06/19/2014] [Indexed: 05/19/2023]
Abstract
Light is essential for the life of photosynthetic organisms as it is a source of energy and information from the environment. Light excess or limitation can be a cause of stress however. Photosynthetic organisms exhibit sophisticated mechanisms to adjust their physiology and growth to the local environmental light conditions. The cryptochrome/photolyase family (CPF) is composed of flavoproteins with similar structures that display a variety of light-dependent functions. This family encompasses photolyases, blue-light activated enzymes that repair ultraviolet-light induced DNA damage, and cryptochromes, known for their photoreceptor functions in terrestrial plants. For this review, we searched extensively for CPFs in the available genome databases to trace the distribution and evolution of this protein family in photosynthetic organisms. By merging molecular data with current knowledge from the functional characterization of CPFs from terrestrial and aquatic organisms, we discuss their roles in (i) photoperception, (ii) biological rhythm regulation and (iii) light-induced stress responses. We also explore their possible implication in light-related physiological acclimation and their distribution in phototrophs living in different environments. The outcome of this structure-function analysis reconstructs the complex scenarios in which CPFs have evolved, as highlighted by the novel functions and biochemical properties of the most recently described family members in algae.
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Affiliation(s)
- Antonio Emidio Fortunato
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France; CNRS, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France
| | - Rossella Annunziata
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France; CNRS, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France
| | - Marianne Jaubert
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France; CNRS, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France
| | - Jean-Pierre Bouly
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France; CNRS, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France.
| | - Angela Falciatore
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France; CNRS, UMR 7238, Computational and Quantitative Biology, F-75006 Paris, France.
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Abstract
As major contributors to global oxygen levels and producers of fatty acids, carotenoids, sterols, and phycocolloids, algae have significant ecological and commercial roles. Early algal models have contributed much to our understanding of circadian clocks at physiological and biochemical levels. The genetic and molecular approaches that identified clock components in other taxa have not been as widely applied to algae. We review results from seven species: the chlorophytes Chlamydomonas reinhardtii, Ostreococcus tauri, and Acetabularia spp.; the dinoflagellates Lingulodinium polyedrum and Symbiodinium spp.; the euglenozoa Euglena gracilis; and the red alga Cyanidioschyzon merolae. The relative simplicity, experimental tractability, and ecological and evolutionary diversity of algal systems may now make them particularly useful in integrating quantitative data from "omic" technologies (e.g., genomics, transcriptomics, metabolomics, and proteomics) with computational and mathematical methods.
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Affiliation(s)
- Zeenat B Noordally
- SynthSys and School of Biological Sciences, University of Edinburgh , Edinburgh EH9 3BF, United Kingdom
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Hense A, Herman E, Oldemeyer S, Kottke T. Proton transfer to flavin stabilizes the signaling state of the blue light receptor plant cryptochrome. J Biol Chem 2014; 290:1743-51. [PMID: 25471375 DOI: 10.1074/jbc.m114.606327] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Plant cryptochromes regulate the circadian rhythm, flowering time, and photomorphogenesis in higher plants as responses to blue light. In the dark, these photoreceptors bind oxidized FAD in the photolyase homology region (PHR). Upon blue light absorption, FAD is converted to the neutral radical state, the likely signaling state, by electron transfer via a conserved tryptophan triad and proton transfer from a nearby aspartic acid. Here we demonstrate, by infrared and time-resolved UV-visible spectroscopy on the PHR domain, that replacement of the aspartic acid Asp-396 with cysteine prevents proton transfer. The lifetime of the radical is decreased by 6 orders of magnitude. This short lifetime does not permit to drive conformational changes in the C-terminal extension that have been associated with signal transduction. Only in the presence of ATP do both the wild type and mutant form a long-lived radical state. However, in the mutant, an anion radical is formed instead of the neutral radical, as found previously in animal type I cryptochromes. Infrared spectroscopic experiments demonstrate that the light-induced conformational changes of the PHR domain are conserved in the mutant despite the lack of proton transfer. These changes are not detected in the photoreduction of the non-photosensory d-amino acid oxidase to the anion radical. In conclusion, formation of the anion radical is sufficient to generate a protein response in plant cryptochromes. Moreover, the intrinsic proton transfer is required for stabilization of the signaling state in the absence of ATP.
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Affiliation(s)
- Anika Hense
- From the Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Elena Herman
- From the Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Sabine Oldemeyer
- From the Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Tilman Kottke
- From the Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615 Bielefeld, Germany
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Transcriptional analysis of Volvox photoreceptors suggests the existence of different cell-type specific light-signaling pathways. Curr Genet 2014; 61:3-18. [PMID: 25117716 DOI: 10.1007/s00294-014-0440-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 07/10/2014] [Accepted: 07/25/2014] [Indexed: 12/14/2022]
Abstract
Photosynthetic organisms, e.g., plants including green algae, use a sophisticated light-sensing system, composed of primary photoreceptors and additional downstream signaling components, to monitor changes in the ambient light environment towards adjust their growth and development. Although a variety of cellular processes, e.g., initiation of cleavage division and final cellular differentiation, have been shown to be light-regulated in the green alga Volvox carteri, little is known about the underlying light perception and signaling pathways. This multicellular alga possesses at least 12 photoreceptors, i.e., one phototropin (VcPhot), four cryptochromes (VcCRYa, VcCRYp, VcCRYd1, and VcCRYd2), and seven members of rhodopsin-like photoreceptors (VR1, VChR1, VChR2, VcHKR1, VcHKR2, VcHKR3, and VcHKR4), which display distinct light-dependent chemical processes based on their protein architectures and associated chromophores. Gene expression analyses could show that the transcript levels of some of the photoreceptor genes (e.g., VChR1 and VcHKR1) accumulate during division cleavages, while others (e.g., VcCRYa, VcCRYp, and VcPhot) accumulate during final cellular differentiation. However, the pattern of transcript accumulation changes when the alga switches to the sexual development. Eight photoreceptor genes, e.g., VcPhot, VcCRYp, and VcHKR1, are highly expressed in the somatic cells, while only the animal-type rhodopsin VR1 was found to be highly expressed in the reproductive cells/embryos during both asexual and sexual life cycles. Moreover, accumulation of VChR1 and VcCRYa transcripts is more sensitive to light and changes in response to more than one light quality. Obviously, different regulatory mechanisms underlying gene expression control transcript accumulation of photoreceptors not only during development, but also in a cell-type specific way and in response to various external signals such as light quality. The transcriptional patterns described in this study show that Volvox photoreceptors are mostly expressed in a cell-type specific manner. This gives reason to believe that cell-type specific light-signaling pathways allow differential regulation of cellular and developmental processes in response to the environmental light cues.
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Perrineau MM, Gross J, Zelzion E, Price DC, Levitan O, Boyd J, Bhattacharya D. Using natural selection to explore the adaptive potential of Chlamydomonas reinhardtii. PLoS One 2014; 9:e92533. [PMID: 24658261 PMCID: PMC3962425 DOI: 10.1371/journal.pone.0092533] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 02/24/2014] [Indexed: 11/18/2022] Open
Abstract
Improving feedstock is critical to facilitate the commercial utilization of algae, in particular in open pond systems where, due to the presence of competitors and pests, high algal growth rates and stress tolerance are beneficial. Here we raised laboratory cultures of the model alga Chlamydomonas reinhardtii under serial dilution to explore the potential of crop improvement using natural selection. The alga was evolved for 1,880 generations in liquid medium under continuous light (EL population). At the end of the experiment, EL cells had a growth rate that was 35% greater than the progenitor population (PL). The removal of acetate from the medium demonstrated that EL growth enhancement largely relied on efficient usage of this organic carbon source. Genome re-sequencing uncovered 1,937 polymorphic DNA regions in the EL population with 149 single nucleotide polymorphisms resulting in amino acid substitutions. Transcriptome analysis showed, in the EL population, significant up regulation of genes involved in protein synthesis, the cell cycle and cellular respiration, whereas the DNA repair pathway and photosynthesis were down regulated. Like other algae, EL cells accumulated neutral lipids under nitrogen depletion. Our work demonstrates transcriptome and genome-wide impacts of natural selection on algal cells and points to a useful strategy for strain improvement.
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Affiliation(s)
- Marie-Mathilde Perrineau
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Jeferson Gross
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Ehud Zelzion
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Dana C. Price
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Orly Levitan
- Institute of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Jeffrey Boyd
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey, United States of America
| | - Debashish Bhattacharya
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, New Jersey, United States of America
- Institute of Marine and Coastal Science, Rutgers University, New Brunswick, New Jersey, United States of America
- * E-mail:
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Forbes-Stovall J, Howton J, Young M, Davis G, Chandler T, Kessler B, Rinehart CA, Jacobshagen S. Chlamydomonas reinhardtii strain CC-124 is highly sensitive to blue light in addition to green and red light in resetting its circadian clock, with the blue-light photoreceptor plant cryptochrome likely acting as negative modulator. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 75:14-23. [PMID: 24361506 PMCID: PMC3938392 DOI: 10.1016/j.plaphy.2013.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 12/03/2013] [Indexed: 05/20/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii has long served as model organism for studies on the circadian clock. This clock is present in all eukaryotes and some prokaryotes allowing them to anticipate and take advantage of the daily oscillations in the environment. Although much is known about the circadian clock in C. reinhardtii, the photoreceptors mediating entrainment of the clock to the daily changes of light remain obscure. Based on its circadian rhythm of phototaxis as a reporter of the clock's phase, we show here that C. reinhardtii strain CC-124 is highly sensitive to blue light of 440 nm when resetting its circadian clock upon light pulses. Thus, CC-124 differs in this respect from what was previously reported for a cell wall-deficient strain. An action spectrum analysis revealed that CC-124 also responds with high sensitivity to green (540 nm), red (640-660 nm), and possibly UV-A (≤400 nm) light, and therefore shows similarities as well to what has been reported for the cell wall-deficient strain. We also investigated two RNA interference strains with reductions in the level of the blue light photoreceptor plant cryptochrome (CPH1). One of them, the strain with the greater reduction, surprisingly showed an increased sensitivity in clock resetting upon blue light pulses of 440 nm. This increase in sensitivity reverted to wild-type levels when the RNA interference strain reverted to wild-type protein levels. It suggests that plant cryptochrome in C. reinhardtii could function as negative rather than positive modulator of circadian clock resetting.
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Affiliation(s)
- Jennifer Forbes-Stovall
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Jonathan Howton
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Matthew Young
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Gavin Davis
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Todd Chandler
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Bruce Kessler
- Department of Mathematics, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Claire A Rinehart
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA
| | - Sigrid Jacobshagen
- Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101, USA.
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Kianianmomeni A, Hallmann A. Algal photoreceptors: in vivo functions and potential applications. PLANTA 2014; 239:1-26. [PMID: 24081482 DOI: 10.1007/s00425-013-1962-5] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/09/2013] [Indexed: 06/02/2023]
Abstract
Many algae, particularly microalgae, possess a sophisticated light-sensing system including photoreceptors and light-modulated signaling pathways to sense environmental information and secure the survival in a rapidly changing environment. Over the last couple of years, the multifaceted world of algal photobiology has enriched our understanding of the light absorption mechanisms and in vivo function of photoreceptors. Moreover, specific light-sensitive modules have already paved the way for the development of optogenetic tools to generate light switches for precise and spatial control of signaling pathways in individual cells and even in complex biological systems.
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Affiliation(s)
- Arash Kianianmomeni
- Department of Cellular and Developmental Biology of Plants, University of Bielefeld, Universitätsstr. 25, 33615, Bielefeld, Germany,
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Phase-resetting mechanism of the circadian clock in Chlamydomonas reinhardtii. Proc Natl Acad Sci U S A 2013; 110:13666-71. [PMID: 23898163 DOI: 10.1073/pnas.1220004110] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Although the circadian clock is a self-sustaining oscillator having a periodicity of nearly 1 d, its period length is not necessarily 24 h. Therefore, daily adjustment of the clock (i.e., resetting) is an essential mechanism for the circadian clock to adapt to daily environmental changes. One of the major cues for this resetting mechanism is light. In the unicellular green alga Chlamydomonas reinhardtii, the circadian clock is reset by blue/green and red light. However, the underlying molecular mechanisms remain largely unknown. In this study, using clock protein-luciferase fusion reporters, we found that the level of RHYTHM OF CHLOROPLAST 15 (ROC15), a clock component in C. reinhardtii, decreased rapidly after light exposure in a circadian-phase-independent manner. Blue, green, and red light were able to induce this process, with red light being the most effective among them. Expression analyses and inhibitor experiments suggested that this process was regulated mainly by a proteasome-dependent protein degradation pathway. In addition, we found that the other clock gene, ROC114, encoding an F-box protein, was involved in this process. Furthermore, we demonstrated that a roc15 mutant showed defects in the phase-resetting of the circadian clock by light. Taken together, these data strongly suggest that the light-induced degradation of ROC15 protein is one of the triggers for resetting the circadian clock in C. reinhardtii. Our data provide not only a basis for understanding the molecular mechanisms of light-induced phase-resetting in C. reinhardtii, but also insights into the phase-resetting mechanisms of circadian clocks in plants.
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Strenkert D, Schmollinger S, Schroda M. Heat shock factor 1 counteracts epigenetic silencing of nuclear transgenes in Chlamydomonas reinhardtii. Nucleic Acids Res 2013; 41:5273-89. [PMID: 23585280 PMCID: PMC3664811 DOI: 10.1093/nar/gkt224] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We found previously that the Chlamydomonas HSP70A promoter counteracts transcriptional silencing of downstream promoters in a transgene setting. To elucidate the underlying mechanisms, we analyzed chromatin state and transgene expression in transformants containing HSP70A-RBCS2-ble (AR-ble) constructs harboring deletions/mutations in the A promoter. We identified histone modifications at transgenic R promoters indicative for repressive chromatin, i.e. low levels of histone H3/4 acetylation and H3-lysine 4 trimethylation and high levels of H3-lysine 9 monomethylation. Transgenic A promoters also harbor lower levels of active chromatin marks than the native A promoter, but levels were higher than those at transgenic R promoters. Strikingly, in AR promoter fusions, the chromatin state at the A promoter was transferred to R. This effect required intact HSE4, HSE1/2 and TATA-box in the A promoter and was mediated by heat shock factor (HSF1). However, time-course analyses in strains inducibly depleted of HSF1 revealed that a transcriptionally competent chromatin state alone was not sufficient for activating the R promoter, but required constitutive HSF1 occupancy at transgenic A. We propose that HSF1 constitutively forms a scaffold at the transgenic A promoter, presumably containing mediator and TFIID, from which local chromatin remodeling and polymerase II recruitment to downstream promoters is realized.
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Affiliation(s)
- Daniela Strenkert
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
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Beel B, Müller N, Kottke T, Mittag M. News about cryptochrome photoreceptors in algae. PLANT SIGNALING & BEHAVIOR 2013; 8:e22870. [PMID: 23154511 PMCID: PMC3656988 DOI: 10.4161/psb.22870] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Cryptochromes (CRYs) are flavoproteins that are known as blue light photoreceptors in many organisms. Recently, genome sequences from a variety of algae became available. Functional characterizations of animal-like CRYs from Oestreococcus tauri, Chlamydomonas reinhardtii and Phaeodactylum tricornutum highlighted novel functions and properties. As arising from studies in fungi, certain algal CRYs of the "cryptochrome photolyase family" (PtCPF1, OtCPF1) have dual or even triple functions. They are involved in blue light perception and/or in the circadian clock and are able to repair DNA damages. On the other hand, the animal-like aCRY from C. reinhardtii is not only acting as sensory blue light- but also as sensory red light receptor thus expanding our current view of flavoproteins in general and CRYs in particular. The observed broad spectral response points to the neutral radical state of flavin, which is assumed to be the dark form in aCRY in contrast to the plant CRYs.
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Affiliation(s)
- Benedikt Beel
- Institute of General Botany and Plant Physiology; Friedrich Schiller University Jena; Jena, Germany
| | - Nico Müller
- Institute of General Botany and Plant Physiology; Friedrich Schiller University Jena; Jena, Germany
| | - Tilman Kottke
- Physical and Biophysical Chemistry; Department of Chemistry; Bielefeld University; Bielefeld, Germany
| | - Maria Mittag
- Institute of General Botany and Plant Physiology; Friedrich Schiller University Jena; Jena, Germany
- Correspondence to: Maria Mittag,
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Trippens J, Greiner A, Schellwat J, Neukam M, Rottmann T, Lu Y, Kateriya S, Hegemann P, Kreimer G. Phototropin influence on eyespot development and regulation of phototactic behavior in Chlamydomonas reinhardtii. THE PLANT CELL 2012; 24:4687-4702. [PMID: 23204408 PMCID: PMC3531860 DOI: 10.1105/tpc.112.103523] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 10/21/2012] [Accepted: 11/09/2012] [Indexed: 05/21/2023]
Abstract
The eyespot of Chlamydomonas reinhardtii is a light-sensitive organelle important for phototactic orientation of the alga. Here, we found that eyespot size is strain specific and downregulated in light. In a strain in which the blue light photoreceptor phototropin was deleted by homologous recombination, the light regulation of the eyespot size was affected. We restored this dysfunction in different phototropin complementation experiments. Complementation with the phototropin kinase fragment reduced the eyespot size, independent of light. Interestingly, overexpression of the N-terminal light, oxygen or voltage sensing domains (LOV1+LOV2) alone also affected eyespot size and phototaxis, suggesting that aside from activation of the kinase domain, they fulfill an independent signaling function in the cell. Moreover, phototropin is involved in adjusting the level of channelrhodopsin-1, the dominant primary receptor for phototaxis within the eyespot. Both the level of channelrhodopsin-1 at the onset of illumination and its steady state level during the light period are downregulated by phototropin, whereas the level of channelrhodopsin-2 is not significantly altered. Furthermore, a light intensity-dependent formation of a C-terminal truncated phototropin form was observed. We propose that phototropin is a light regulator of phototaxis that desensitizes the eyespot when blue light intensities increase.
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Affiliation(s)
- Jessica Trippens
- Department of Biology, Friedrich-Alexander-University, 91058 Erlangen, Germany
| | - Andre Greiner
- Institute for Experimental Biophysics, Humboldt University, 10115 Berlin, Germany
| | - Jana Schellwat
- Department of Biology, Friedrich-Alexander-University, 91058 Erlangen, Germany
| | - Martin Neukam
- Department of Biology, Friedrich-Alexander-University, 91058 Erlangen, Germany
| | - Theresa Rottmann
- Department of Biology, Friedrich-Alexander-University, 91058 Erlangen, Germany
| | - Yinghong Lu
- Institute for Experimental Biophysics, Humboldt University, 10115 Berlin, Germany
| | - Suneel Kateriya
- Department of Biochemistry, University of Delhi South Campus, 110021 Delhi, India
| | - Peter Hegemann
- Institute for Experimental Biophysics, Humboldt University, 10115 Berlin, Germany
| | - Georg Kreimer
- Department of Biology, Friedrich-Alexander-University, 91058 Erlangen, Germany
- Erlangen Center of Plant Science, Friedrich-Alexander-University, 91058 Erlangen, Germany
- Address correspondence to
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41
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Beel B, Prager K, Spexard M, Sasso S, Weiss D, Müller N, Heinnickel M, Dewez D, Ikoma D, Grossman AR, Kottke T, Mittag M. A flavin binding cryptochrome photoreceptor responds to both blue and red light in Chlamydomonas reinhardtii. THE PLANT CELL 2012; 24:2992-3008. [PMID: 22773746 PMCID: PMC3426128 DOI: 10.1105/tpc.112.098947] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 05/31/2012] [Accepted: 06/22/2012] [Indexed: 05/19/2023]
Abstract
Cryptochromes are flavoproteins that act as sensory blue light receptors in insects, plants, fungi, and bacteria. We have investigated a cryptochrome from the green alga Chlamydomonas reinhardtii with sequence homology to animal cryptochromes and (6-4) photolyases. In response to blue and red light exposure, this animal-like cryptochrome (aCRY) alters the light-dependent expression of various genes encoding proteins involved in chlorophyll and carotenoid biosynthesis, light-harvesting complexes, nitrogen metabolism, cell cycle control, and the circadian clock. Additionally, exposure to yellow but not far-red light leads to comparable increases in the expression of specific genes; this expression is significantly reduced in an acry insertional mutant. These in vivo effects are congruent with in vitro data showing that blue, yellow, and red light, but not far-red light, are absorbed by the neutral radical state of flavin in aCRY. The aCRY neutral radical is formed following blue light absorption of the oxidized flavin. Red illumination leads to conversion to the fully reduced state. Our data suggest that aCRY is a functionally important blue and red light-activated flavoprotein. The broad spectral response implies that the neutral radical state functions as a dark form in aCRY and expands the paradigm of flavoproteins and cryptochromes as blue light sensors to include other light qualities.
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Affiliation(s)
- Benedikt Beel
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Katja Prager
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Meike Spexard
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Severin Sasso
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
- Leibniz Institute for Natural Product Research and Infection Biology, 07745 Jena, Germany
| | - Daniel Weiss
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Nico Müller
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
| | - Mark Heinnickel
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - David Dewez
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Danielle Ikoma
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Arthur R. Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Tilman Kottke
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Maria Mittag
- Institute of General Botany and Plant Physiology, Friedrich Schiller University, 07743 Jena, Germany
- Address correspondence to
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Heijde M, Zabulon G, Corellou F, Ishikawa T, Brazard J, Usman A, Sanchez F, Plaza P, Martin M, Falciatore A, Todo T, Bouget FY, Bowler C. Characterization of two members of the cryptochrome/photolyase family from Ostreococcus tauri provides insights into the origin and evolution of cryptochromes. PLANT, CELL & ENVIRONMENT 2010; 33:1614-1626. [PMID: 20444223 DOI: 10.1111/j.1365-3040.2010.02168.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Cryptochromes (Crys) are blue light receptors believed to have evolved from the DNA photolyase protein family, implying that light control and light protection share a common ancient origin. In this paper, we report the identification of five genes of the Cry/photolyase family (CPF) in two green algae of the Ostreococcus genus. Phylogenetic analyses were used to confidently assign three of these sequences to cyclobutane pyrimidine dimer (CPD) photolyases, one of them to a DASH-type Cry, and a third CPF gene has high homology with the recently described diatom CPF1 that displays a bifunctional activity. Both purified OtCPF1 and OtCPF2 proteins show non-covalent binding to flavin adenine dinucleotide (FAD), and additionally to 5,10-methenyl-tetrahydrofolate (MTHF) for OtCPF2. Expression analyses revealed that all five CPF members of Ostreococcus tauri are regulated by light. Furthermore, we show that OtCPF1 and OtCPF2 display photolyase activity and that OtCPF1 is able to interact with the CLOCK:BMAL heterodimer, transcription factors regulating circadian clock function in other organisms. Finally, we provide evidence for the involvement of OtCPF1 in the maintenance of the Ostreococcus circadian clock. This work improves our understanding of the evolutionary transition between photolyases and Crys.
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Affiliation(s)
- Marc Heijde
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, IBENS, CNRS UMR 8197, Paris, F-75005 France
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Yu X, Liu H, Klejnot J, Lin C. The Cryptochrome Blue Light Receptors. THE ARABIDOPSIS BOOK 2010; 8:e0135. [PMID: 21841916 PMCID: PMC3155252 DOI: 10.1199/tab.0135] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Cryptochromes are photolyase-like blue light receptors originally discovered in Arabidopsis but later found in other plants, microbes, and animals. Arabidopsis has two cryptochromes, CRY1 and CRY2, which mediate primarily blue light inhibition of hypocotyl elongation and photoperiodic control of floral initiation, respectively. In addition, cryptochromes also regulate over a dozen other light responses, including circadian rhythms, tropic growth, stomata opening, guard cell development, root development, bacterial and viral pathogen responses, abiotic stress responses, cell cycles, programmed cell death, apical dominance, fruit and ovule development, seed dormancy, and magnetoreception. Cryptochromes have two domains, the N-terminal PHR (Photolyase-Homologous Region) domain that bind the chromophore FAD (flavin adenine dinucleotide), and the CCE (CRY C-terminal Extension) domain that appears intrinsically unstructured but critical to the function and regulation of cryptochromes. Most cryptochromes accumulate in the nucleus, and they undergo blue light-dependent phosphorylation or ubiquitination. It is hypothesized that photons excite electrons of the flavin molecule, resulting in redox reaction or circular electron shuttle and conformational changes of the photoreceptors. The photoexcited cryptochrome are phosphorylated to adopt an open conformation, which interacts with signaling partner proteins to alter gene expression at both transcriptional and posttranslational levels and consequently the metabolic and developmental programs of plants.
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Affiliation(s)
- Xuhong Yu
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA
| | - Hongtao Liu
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA
| | - John Klejnot
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA
| | - Chentao Lin
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA
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Schulze T, Prager K, Dathe H, Kelm J, Kiessling P, Mittag M. How the green alga Chlamydomonas reinhardtii keeps time. PROTOPLASMA 2010; 244:3-14. [PMID: 20174954 DOI: 10.1007/s00709-010-0113-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 01/18/2010] [Indexed: 05/10/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii has two flagella and a primitive visual system, the eyespot apparatus, which allows the cell to phototax. About 40 years ago, it was shown that the circadian clock controls its phototactic movement. Since then, several circadian rhythms such as chemotaxis, cell division, UV sensitivity, adherence to glass, or starch metabolism have been characterized. The availability of its entire genome sequence along with homology studies and the analysis of several sub-proteomes render C. reinhardtii as an excellent eukaryotic model organism to study its circadian clock at different levels of organization. Previous studies point to several potential photoreceptors that may be involved in forwarding light information to entrain its clock. However, experimental data are still missing toward this end. In the past years, several components have been functionally characterized that are likely to be part of the oscillatory machinery of C. reinhardtii since alterations in their expression levels or insertional mutagenesis of the genes resulted in defects in phase, period, or amplitude of at least two independent measured rhythms. These include several RHYTHM OF CHLOROPLAST (ROC) proteins, a CONSTANS protein (CrCO) that is involved in parallel in photoperiodic control, as well as the two subunits of the circadian RNA-binding protein CHLAMY1. The latter is also tightly connected to circadian output processes. Several candidates including a significant number of ROCs, CrCO, and CASEIN KINASE1 whose alterations of expression affect the circadian clock have in parallel severe effects on the release of daughter cells, flagellar formation, and/or movement, indicating that these processes are interconnected in C. reinhardtii. The challenging task for the future will be to get insights into the clock network and to find out how the clock-related factors are functionally connected. In this respect, system biology approaches will certainly contribute in the future to improve our understanding of the C. reinhardtii clock machinery.
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Affiliation(s)
- Thomas Schulze
- Institute of General Botany and Plant Physiology, Friedrich-Schiller-University, Am Planetarium 1, 07743, Jena, Germany
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Carolaing Gabaldón M, Labrador L, Arraiz G, Concepción JL, Avilan L. Trypanosoma cruzi: A kinetoplast-associated protein of the photolyase/cryptochrome family. Exp Parasitol 2010; 124:350-6. [DOI: 10.1016/j.exppara.2009.11.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 11/13/2009] [Accepted: 11/16/2009] [Indexed: 11/30/2022]
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46
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Vlček D, Ševčovičová A, Sviežená B, Gálová E, Miadoková E. Chlamydomonas reinhardtii: a convenient model system for the study of DNA repair in photoautotrophic eukaryotes. Curr Genet 2007; 53:1-22. [DOI: 10.1007/s00294-007-0163-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Revised: 10/08/2007] [Accepted: 10/20/2007] [Indexed: 01/12/2023]
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47
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Shihira-Ishikawa I, Nakamura T, Higashi SI, Watanabe M. Distinct Responses of Chloroplasts to Blue and Green Laser Microbeam Irradiations in the Centric Diatom Pleurosira laevis. Photochem Photobiol 2007; 83:1101-9. [PMID: 17880505 DOI: 10.1111/j.1751-1097.2007.00167.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The centric diatom Pleurosira laevis is a large unicellular alga, in which ca 200 chloroplasts migrate toward the nuclear cytoplasm through the transvacuolar cytoplasmic strands in response to blue-light irradiation and, on the contrary, toward the cortical cytoplasm in response to green-light irradiation. We analyzed these light-induced chloroplast migrations using a scanning laser microbeam provided by a confocal microscope for intracellular irradiation. Spot irradiation of a blue laser microbeam induced rapid assemblage of chroloplasts into the nuclear cytoplasm regardless of the spot position and spot number. On the other hand, one or two spots of green laser microbeam induced chloroplast accumulation at the spots, although increasing spot numbers suppressed chloroplast accumulation at each spot. In our experimental condition, ca 1 min of blue-light irradiation was sufficient to stimulate movement, whereas green-light irradiation required uninterrupted and longer irradiation time (ca 15 min). Chloroplast assemblage induced by blue-light required extracellular Ca2+, and was inhibited by Ca2+ channel antagonists. Furthermore, higher efficiencies of chloroplast migration were obtained when a single beam spot was fragmented and scattered over wider area of plasma membrane. These observations suggested that blue-light induced a response at the plasma membrane, which subsequently activated Ca2+ permeable channels. This sequence of physiological events is identical to what was previously observed with chloroplast movement in response to mechanical stimulation. Furthermore, experiments with the cytoskeleton-disrupting agents, colchicine and cytochalasin D, indicated that blue-light-induced chloroplast movement required microtubules whereas the green-light-induced response to beam spot required actin filaments.
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Immeln D, Schlesinger R, Heberle J, Kottke T. Blue Light Induces Radical Formation and Autophosphorylation in the Light-sensitive Domain of Chlamydomonas Cryptochrome. J Biol Chem 2007; 282:21720-8. [PMID: 17548357 DOI: 10.1074/jbc.m700849200] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cryptochromes are sensory blue light receptors mediating various responses in plants and animals. Studies on the mechanism of plant cryptochromes have been focused on the flowering plant Arabidopsis. In the genome of the unicellular green alga Chlamydomonas reinhardtii, a single plant cryptochrome, Chlamydomonas photolyase homologue 1 (CPH1), has been identified. The N-terminal 500 amino acids comprise the light-sensitive domain of CPH1 linked to a C-terminal extension of similar size. We have expressed the light-sensitive domain heterologously in Escherichia coli in high yield and purity. The 59-kDa protein bears exclusively flavin adenine dinucleotide in its oxidized state. Illumination with blue light induces formation of a neutral flavin radical with absorption maxima at 540 and 580 nm. The reaction proceeds aerobically even in the absence of an exogenous electron donor, which suggests that it reflects a physiological response. The process is completely reversible in the dark and exhibits a decay time constant of 200 s in the presence of oxygen. Binding of ATP strongly stabilizes the radical state after illumination and impedes the dark recovery. Thus, ATP binding has functional significance for plant cryptochromes and does not merely result from structural homology to DNA photolyase. The light-sensitive domain responds to illumination by an increase in phosphorylation. The autophosphorylation takes place although the protein is lacking its native C-terminal extension. This finding indicates that the extension is dispensable for autophosphorylation, despite the role it has been assigned in mediating signal transduction in Arabidopsis.
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Affiliation(s)
- Dominik Immeln
- Institute of Neurosciences and Biophysics-2, Molecular Biophysics, Research Center Jülich, Jülich, Germany
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50
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Im CS, Eberhard S, Huang K, Beck CF, Grossman AR. Phototropin involvement in the expression of genes encoding chlorophyll and carotenoid biosynthesis enzymes and LHC apoproteins in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 48:1-16. [PMID: 16972865 DOI: 10.1111/j.1365-313x.2006.02852.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Phototropin (PHOT) is a photoreceptor involved in a variety of blue-light-elicited physiological processes including phototropism, chloroplast movement and stomatal opening in plants. The work presented here tests whether PHOT is involved in expression of light-regulated genes in Chlamydomonas reinhardtii. When C. reinhardtii was transferred from the dark to very low-fluence rate white light, there was a substantial increase in the level of transcripts encoding glutamate-1-semialdehyde aminotransferase (GSAT), phytoene desaturase (PDS) and light-harvesting polypeptides (e.g. LHCBM6). Increased levels of these transcripts were also elicited by low-intensity blue light, and this blue-light stimulation was suppressed in three different RNAi strains that synthesize low levels of PHOT. The levels of GSAT and LHCBM6 transcripts also increased following exposure of algal cells to low-intensity red light (RL). The red-light-dependent increase in transcript abundance was not affected by the electron transport inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea, implying that the influence of RL on transcript accumulation was not controlled by cytoplasmic redox conditions, and that a red-light photoreceptor(s) may be involved in regulating the levels of transcripts from specific photosynthesis-related genes in C. reinhardtii. Interestingly, elevated GSAT and LHCBM6 transcript levels in RL were significantly reduced in the PHOT RNAi strains, which raises the possibility of co-action between blue and RL signaling pathways. Microarray experiments indicated that the levels of several transcripts for photosystem (PS) I and II polypeptides were also modulated by PHOT. These data suggest that, in C. reinhardtii, (i) PHOT is involved in blue-light-mediated changes in transcript accumulation, (ii) synchronization of the synthesis of chlorophylls (Chl), carotenoids, Chl-binding proteins and other components of the photosynthetic apparatus is achieved, at least in part, through PHOT-mediated signaling, and (iii) a red-light photoreceptor can also influence levels of certain transcripts associated with photosynthetic function, although its action requires normal levels of PHOT.
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Affiliation(s)
- Chung-Soon Im
- Department of Plant Biology, Carnegie Institution, Stanford, CA 94306, USA.
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