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van Midden KP, Mantz M, Fonovič M, Gazvoda M, Svete J, Huesgen PF, van der Hoorn RAL, Klemenčič M. Mechanistic insights into CrCEP1: A dual-function cysteine protease with endo- and transpeptidase activity. Int J Biol Macromol 2024; 271:132505. [PMID: 38768911 DOI: 10.1016/j.ijbiomac.2024.132505] [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: 12/12/2023] [Revised: 04/05/2024] [Accepted: 05/17/2024] [Indexed: 05/22/2024]
Abstract
Proteases, essential regulators of plant stress responses, remain enigmatic in their precise functional roles. By employing activity-based probes for real-time monitoring, this study aimed to delve into protease activities in Chlamydomonas reinhardtii exposed to oxidative stress induced by hydrogen peroxide. However, our work revealed that the activity-based probes strongly labelled three non-proteolytic proteins-PsbO, PsbP, and PsbQ-integral components of photosystem II's oxygen-evolving complex. Subsequent biochemical assays and mass spectrometry experiments revealed the involvement of CrCEP1, a previously uncharacterized papain-like cysteine protease, as the catalyst of this labelling reaction. Further experiments with recombinant CrCEP1 and PsbO proteins replicated the reaction in vitro. Our data unveiled that endopeptidase CrCEP1 also has transpeptidase activity, ligating probes and peptides to the N-termini of Psb proteins, thereby expanding the repertoire of its enzymatic activities. The hitherto unknown transpeptidase activity of CrCEP1, working in conjunction with its proteolytic activity, unveils putative complex and versatile roles for proteases in cellular processes during stress responses.
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Affiliation(s)
- Katarina P van Midden
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Melissa Mantz
- Central Institute for Engineering, Electronics and Analytics, ZEA-3, Forschungszentrum Jülich, Jülich, Germany; CECAD, Medical Faculty and University Hospital, University of Cologne, 50931 Cologne, Germany
| | - Marko Fonovič
- Department of Biochemistry, Molecular and Structural Biology, Jozef Stefan Institute, Ljubljana, Slovenia
| | - Martin Gazvoda
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Jurij Svete
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Pitter F Huesgen
- Central Institute for Engineering, Electronics and Analytics, ZEA-3, Forschungszentrum Jülich, Jülich, Germany; CECAD, Medical Faculty and University Hospital, University of Cologne, 50931 Cologne, Germany; Faculty of Biology, University of Freiburg, Freiburg, Germany; CIBSS- Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | | | - Marina Klemenčič
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia.
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Maruta T, Tanaka Y, Yamamoto K, Ishida T, Hamada A, Ishikawa T. Evolutionary insights into strategy shifts for the safe and effective accumulation of ascorbate in plants. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2664-2681. [PMID: 38452239 DOI: 10.1093/jxb/erae062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 03/06/2024] [Indexed: 03/09/2024]
Abstract
Plants accumulate high concentrations of ascorbate, commonly in their leaves, as a redox buffer. While ascorbate levels have increased during plant evolution, the mechanisms behind this phenomenon are unclear. Moreover, has the increase in ascorbate concentration been achieved without imposing any detrimental effects on the plants? In this review, we focus on potential transitions in two regulatory mechanisms related to ascorbate biosynthesis and the availability of cellular dehydroascorbate (DHA) during plant evolution. The first transition might be that the trigger for the transcriptional induction of VTC2, which encodes the rate-limiting enzyme in ascorbate biosynthesis, has shifted from oxidative stress (in green algae) to light/photosynthesis (in land plants), probably enabling the continuous accumulation of ascorbate under illumination. This could serve as a preventive system against the unpredictable occurrence of oxidative stress. The second transition might be that DHA-degrading enzymes, which protect cells from the highly reactive DHA in green algae and mosses, have been lost in ferns or flowering plants. Instead, flowering plants may have increased glutathione concentrations to reinforce the DHA reduction capacity, possibly allowing ascorbate accumulation and avoiding the toxicity of DHA. These potential transitions may have contributed to strategies for plants' safe and effective accumulation of ascorbate.
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Affiliation(s)
- Takanori Maruta
- Graduate School of Natural Science and Technology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
- Bioresource and Life Sciences, The United Graduate School of Agricultural Sciences, Tottori University, 4-101 Koyama-Minami, Tottori, Tottori 680-8553, Japan
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Yasuhiro Tanaka
- Graduate School of Natural Science and Technology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
- Bioresource and Life Sciences, The United Graduate School of Agricultural Sciences, Tottori University, 4-101 Koyama-Minami, Tottori, Tottori 680-8553, Japan
| | - Kojiro Yamamoto
- Graduate School of Natural Science and Technology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Tetsuya Ishida
- Graduate School of Natural Science and Technology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Akane Hamada
- Graduate School of Natural Science and Technology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
| | - Takahiro Ishikawa
- Graduate School of Natural Science and Technology, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
- Bioresource and Life Sciences, The United Graduate School of Agricultural Sciences, Tottori University, 4-101 Koyama-Minami, Tottori, Tottori 680-8553, Japan
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan
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3
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Lambert L, de Carpentier F, André P, Marchand CH, Danon A. Type II metacaspase mediates light-dependent programmed cell death in Chlamydomonas reinhardtii. PLANT PHYSIOLOGY 2024; 194:2648-2662. [PMID: 37971939 PMCID: PMC10980519 DOI: 10.1093/plphys/kiad618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/12/2023] [Accepted: 10/22/2023] [Indexed: 11/19/2023]
Abstract
Among the crucial processes that preside over the destiny of cells from any type of organism are those involving their self-destruction. This process is well characterized and conceptually logical to understand in multicellular organisms; however, the levels of knowledge and comprehension of its existence are still quite enigmatic in unicellular organisms. We use Chlamydomonas (Chlamydomonas reinhardtii) to lay the foundation for understanding the mechanisms of programmed cell death (PCD) in a unicellular photosynthetic organism. In this paper, we show that while PCD induces the death of a proportion of cells, it allows the survival of the remaining population. A quantitative proteomic analysis aiming at unveiling the proteome of PCD in Chlamydomonas allowed us to identify key proteins that led to the discovery of essential mechanisms. We show that in Chlamydomonas, PCD relies on the light dependence of a photosynthetic organism to generate reactive oxygen species and induce cell death. Finally, we obtained and characterized mutants for the 2 metacaspase genes in Chlamydomonas and showed that a type II metacaspase is essential for PCD execution.
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Affiliation(s)
- Lou Lambert
- Institut de Biologie Paris Seine, UMR 7238, CNRS, Sorbonne Université, Paris 75005, France
| | - Félix de Carpentier
- Institut de Biologie Paris Seine, UMR 7238, CNRS, Sorbonne Université, Paris 75005, France
- Doctoral School of Plant Sciences, Université Paris-Saclay, Saint-Aubin 91190, France
| | - Phuc André
- Institut de Biologie Paris Seine, UMR 7238, CNRS, Sorbonne Université, Paris 75005, France
| | - Christophe H Marchand
- Institut de Biologie Paris Seine, UMR 7238, CNRS, Sorbonne Université, Paris 75005, France
- Institut de Biologie Physico-Chimique, Centre National de la Recherche Scientifique (CNRS), Paris F-75005, France
| | - Antoine Danon
- Institut de Biologie Paris Seine, UMR 7238, CNRS, Sorbonne Université, Paris 75005, France
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4
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Zhang J, Zhang L, Liang D, Yang Y, Geng B, Jing P, Qu Y, Huang J. ROS accumulation-induced tapetal PCD timing changes leads to microspore abortion in cotton CMS lines. BMC PLANT BIOLOGY 2023; 23:311. [PMID: 37308826 DOI: 10.1186/s12870-023-04317-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 05/26/2023] [Indexed: 06/14/2023]
Abstract
BACKGROUND Cytoplasmic male sterility (CMS) is the basis of heterosis exploitation. CMS has been used to hybrid production in cotton, but its molecular mechanism remains unclear. CMS is associated with advanced or delayed tapetal programmed cell death (PCD), and reactive oxygen species (ROS) may mediate this process. In this study, we obtained Jin A and Yamian A, two CMS lines with different cytoplasmic sources. RESULTS Compared with maintainer Jin B, Jin A anthers showed advanced tapetal PCD with DNA fragmentation, producing excessive ROS which accumulated around the cell membrane, intercellular space and mitochondrial membrane. The activities of peroxidase (POD) and catalase (CAT) enzymes which can scavenge ROS were significantly decreased. However, Yamian A tapetal PCD was delayed with lower ROS content, and the activities of superoxide dismutase (SOD) and POD were higher than its maintainer. These differences in ROS scavenging enzyme activities may be caused by isoenzyme gene expressions. In addition, we found the excess ROS generated in Jin A mitochondria and ROS overflow from complex III might be the source in parallel with the reduction of ATP content. CONCLUSION ROS accumulation or abrogation were mainly caused by the joint action of ROS generation and scavenging enzyme activities transformation, which led to the abnormal progression of tapetal PCD, affected the development of microspores, and eventually contributed to male sterility. In Jin A, tapetal PCD in advance might be caused by mitochondrial ROS overproduction, accompanied by energy deficiency. The above studies will provide new insights into the cotton CMS and guide the follow-up research ideas.
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Affiliation(s)
- Jinlong Zhang
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Li Zhang
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Dong Liang
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Yujie Yang
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Biao Geng
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Panpan Jing
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Yunfang Qu
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Jinling Huang
- College of Agriculture, Shanxi Agricultural University, Taigu, 030801, Shanxi, China.
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Xu C, Yu S, Hu J, Effiong K, Ge Z, Tang T, Xiao X. Programmed cell death process in freshwater Microcystis aeruginosa and marine Phaeocystis globosa induced by a plant derived allelochemical. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156055. [PMID: 35598674 DOI: 10.1016/j.scitotenv.2022.156055] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/25/2022] [Accepted: 05/15/2022] [Indexed: 06/15/2023]
Abstract
Harmful algal blooms (HAB) are a serious problem worldwide. Allelochemicals from natural plants were recently thought to be promising anti-algaecide in controlling harmful algae. However, the programmed cell death (PCD) process of algae under allelopathic pressure induced by 5,4'-dihydroxyflavone (5,4'-DHF) was poorly understood. In this study, two common and worldwide distributed microalgae, Microcystis aeruginosa and Phaeocystis globosa were selected as target algae, and the PCD processes induced by 5,4'-DHF were cross-compared between the two species. Both algae species were inhibited significantly by 5,4'-DHF with the relative sensitivity of 0.11. To uncover the PCD progress systematically, signals for PCD triggering, antioxidant enzyme activity, photosynthetic ability variation, caspase-like activities and typical indicators were investigated. In both species, typical indicators of PCD - phosphatidylserine externalization and chromatin condensation - were detected. The intracellular reactive oxygen species (ROS), nitric oxide (NO) and H2O2 were the potential signal molecules to stimulate PCD, and caspase-like activities were activated with an elevation of cytochrome c indicating the initiation of PCD in both species. However, P. globosa responded to 5,4'-DHF immediately after 3 h with the elevation of ROS and not in M. aeruginosa. Antioxidant enzyme activities of superoxide dismutase (SOD) and catalase (CAT) in M. aeruginosa and P. globosa also showed different patterns on day 3. Specifically, SOD activity in M. aeruginosa increased significantly while it decreased significantly in P. globosa, CAT activity in M. aeruginosa decreased significantly while it increased significantly in P. globosa (p < 0.05). Malondialdehyde (MDA) content in P. globosa increased significantly (p < 0.001) while it showed no variation in M. aeruginosa. Overall, this study is one of the earliest studies to explore the inhibition and action mechanism of plant derived flavonoids on harmful algae from the perspective of PCD, and provide new insights into the antialgal mechanism of allelochemicals.
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Affiliation(s)
- Caicai Xu
- Zhejiang University, Ocean College, 1 Zheda Road, Zhoushan, Zhejiang 316000, China
| | - Shumiao Yu
- Zhejiang University, Ocean College, 1 Zheda Road, Zhoushan, Zhejiang 316000, China
| | - Jing Hu
- Zhejiang University, Ocean College, 1 Zheda Road, Zhoushan, Zhejiang 316000, China
| | - Kokoette Effiong
- Zhejiang University, Ocean College, 1 Zheda Road, Zhoushan, Zhejiang 316000, China
| | - Zhiwei Ge
- Zhejiang University, Analysis Center of Agrobiology and Environmental Sciences, Hangzhou 310058, China
| | - Tao Tang
- Zhejiang University, Ocean College, 1 Zheda Road, Zhoushan, Zhejiang 316000, China
| | - Xi Xiao
- Zhejiang University, Ocean College, 1 Zheda Road, Zhoushan, Zhejiang 316000, China; Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of Ministry of Water Resources, College of Environmental and Resources Sciences, Zhejiang University, Hangzhou 310058, China.
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6
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Iqbal S, Bai Y, Hayat F, Coulibaly D, Khalil-Ur-Rehman M, Shi T, Gao Z. Comprehensive transcriptomic and metabolomic analysis revealed distinct flavonoid biosynthesis regulation during abnormal pistil development in Japanese apricot. Genomics 2022; 114:110451. [PMID: 35988654 DOI: 10.1016/j.ygeno.2022.110451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 08/06/2022] [Accepted: 08/16/2022] [Indexed: 11/27/2022]
Abstract
Japanese apricot is an imperative stone fruit plant with numerous processing importance. The failure of reproductive system is the most common cause of fruit loss, through which pistil abortion is the fundamental one. To understand this mechanism, we used a combination of transcriptomic and metabolomic approaches to investigate the biochemical and molecular basis of flavonoid biosynthesis. Due to the regulated expression of flavonoid pathway-related genes in plants, flavonoid biosynthesis is largely regulated at the transcriptional level. A total of 2272 differently expressed genes and 215 differential metabolites were found. The expression of the genes and metabolites encoding flavonoid biosynthesis was lower in abnormal pistils that are in line with the flavonoid quantification from abnormal pistils. Besides, a couple of genes were also detected related to MYB, MADS, NAC and bHLH transcription factors. Remarkably, we found 'hydroxycinnamoyl transferase (LOC103323133)' and flavonoid related metabolite '2-hydroxycinnamic acid' was lower expressed in abnormal pistil, proposing the cause of pistil abortion. Collectively, the present study delivers inclusive transcriptional and metabolic datasets that proposed valuable prospects to unravel the genetic mechanism underlying pistil abortion.
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Affiliation(s)
- Shahid Iqbal
- Laboratory of Fruit Tree Biotechnology, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China; College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA.
| | - Yang Bai
- Laboratory of Fruit Tree Biotechnology, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
| | - Faisal Hayat
- Laboratory of Fruit Tree Biotechnology, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
| | - Daouda Coulibaly
- Laboratory of Fruit Tree Biotechnology, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
| | | | - Ting Shi
- Laboratory of Fruit Tree Biotechnology, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
| | - Zhihong Gao
- Laboratory of Fruit Tree Biotechnology, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
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Leung C, Grulois D, Chevin LM. Plasticity across levels: relating epigenomic, transcriptomic, and phenotypic responses to osmotic stress in a halotolerant microalga. Mol Ecol 2022; 31:4672-4687. [PMID: 35593517 PMCID: PMC9543585 DOI: 10.1111/mec.16542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 05/12/2022] [Indexed: 12/01/2022]
Abstract
Phenotypic plasticity, the ability of a given genotype to produce alternative phenotypes in response to its environment of development, is an important mechanism for coping with variable environments. While the mechanisms underlying phenotypic plasticity are diverse, their relative contributions need to be investigated quantitatively to better understand the evolvability of plasticity across biological levels. This requires relating plastic responses of the epigenome, transcriptome, and organismal phenotype, and investigating how they vary with the genotype. Here we carried out this approach for responses to osmotic stress in Dunaliella salina, a green microalga that is a model organism for salinity tolerance. We compared two strains that show markedly different demographic responses to osmotic stress, and showed that these phenotypic responses involve strain‐ and environment‐specific variation in gene expression levels, but a relative low—albeit significant—effect of strain × environment interaction. We also found an important genotype effect on the genome‐wide methylation pattern, but little contribution from environmental conditions to the latter. However, we did detect a significant marginal effect of epigenetic variation on gene expression, beyond the influence of genetic differences on epigenetic state, and we showed that hypomethylated regions are correlated with higher gene expression. Our results indicate that epigenetic mechanisms are either not involved in the rapid plastic response to environmental change in this species, or involve only few changes in trans that are sufficient to trigger concerted changes in the expression of many genes, and phenotypic responses by multiple traits.
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Affiliation(s)
- Christelle Leung
- CEFE, Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Daphné Grulois
- CEFE, Université de Montpellier, CNRS, EPHE, IRD, Montpellier, France
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8
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Ben-Sheleg A, Khozin-Godberg I, Yaakov B, Vonshak A. Characterization of Nannochloropsis oceanica Rose Bengal Mutants Sheds Light on Acclimation Mechanisms to High Light When Grown in Low Temperature. PLANT & CELL PHYSIOLOGY 2021; 62:1478-1493. [PMID: 34180533 PMCID: PMC8600018 DOI: 10.1093/pcp/pcab094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 06/23/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
A barrier to realizing Nannochloropsis oceanica's potential for omega-3 eicosapentaenoic acid (EPA) production is the disparity between conditions that are optimal for growth and those that are optimal for EPA biomass content. A case in point is temperature: higher content of polyunsaturated fatty acid, and especially EPA, is observed in low-temperature (LT) environments, where growth rates are often inhibited. We hypothesized that mutant strains of N. oceanica resistant to the singlet-oxygen photosensitizer Rose Bengal (RB) would withstand the oxidative stress conditions that prevail in the combined stressful environment of high light (HL; 250 μmol photons m-2 s-1) and LT (18°C). This growth environment caused the wild-type (WT) strain to experience a spike in lipid peroxidation and an inability to proliferate, whereas growth and homeostatic reactive oxygen species levels were observed in the mutant strains. We suggest that the mutant strains' success in this environment can be attributed to their truncated photosystem II antennas and their increased ability to diffuse energy in those antennas as heat (non-photosynthetic quenching). As a result, the mutant strains produced upward of four times more EPA than the WT strain in this HL-LT environment. The major plastidial lipid monogalactosyldiacylglycerol was a likely target for oxidative damage, contributing to the photosynthetic inhibition of the WT strain. A mutation in the NO10G01010.1 gene, causing a subunit of the 2-oxoisovalerate dehydrogenase E1 protein to become non-functional, was determined to be the likely source of tolerance in the RB113 mutant strain.
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Affiliation(s)
- Avraham Ben-Sheleg
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel
| | - Inna Khozin-Godberg
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel
| | - Beery Yaakov
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel
| | - Avigad Vonshak
- Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion 8499000, Israel
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Feldmesser E, Ben-Dor S, Vardi A. An Emiliania huxleyi pan-transcriptome reveals basal strain specificity in gene expression patterns. Sci Rep 2021; 11:20795. [PMID: 34675226 PMCID: PMC8531018 DOI: 10.1038/s41598-021-00072-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 09/08/2021] [Indexed: 11/09/2022] Open
Abstract
Emiliania huxleyi is a cosmopolitan coccolithophore widespread in temperate oceans. This unicellular photoautotroph forms massive recurring blooms that play an important role in large biogeochemical cycles of carbon and sulfur, which play a role in climate change. The mechanism of bloom formation and demise, controlled by giant viruses that routinely infect these blooms, is poorly understood. We generated a pan-transcriptome of E. huxleyi, derived from three strains with different susceptibility to viral infection. Expression profiling of E. huxleyi sensitive and resistant strains showed major basal differences, including many genes that are induced upon viral infection. This suggests that basal gene expression can affect the host metabolic state and the susceptibility of E. huxleyi to viruses. Due to its ecological importance, the pan-transcriptome and its protein translation, applicable to many E. huxleyi strains, is a powerful resource for investigation of eukaryotic microbial communities.
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Affiliation(s)
- Ester Feldmesser
- Bioinformatics Unit, Life Sciences Core Facilities, Weizmann Institute of Science, 7610001, Rehovot, Israel
| | - Shifra Ben-Dor
- Bioinformatics Unit, Life Sciences Core Facilities, Weizmann Institute of Science, 7610001, Rehovot, Israel.
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, 7610001, Rehovot, Israel
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10
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Sodeyama T, Nishikawa H, Harai K, Takeshima D, Sawa Y, Maruta T, Ishikawa T. The d-mannose/l-galactose pathway is the dominant ascorbate biosynthetic route in the moss Physcomitrium patens. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1724-1738. [PMID: 34245628 DOI: 10.1111/tpj.15413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/16/2021] [Accepted: 07/06/2021] [Indexed: 05/14/2023]
Abstract
Ascorbate is an abundant and indispensable redox compound in plants. Genetic and biochemical studies have established the d-mannose/l-galactose (d-Man/l-Gal) pathway as the predominant ascorbate biosynthetic pathway in streptophytes, while the d-galacturonate (d-GalUA) pathway is found in prasinophytes and euglenoids. Based on the presence of the complete set of genes encoding enzymes involved in the d-Man/l-Gal pathway and an orthologous gene encoding aldonolactonase (ALase) - a key enzyme for the d-GalUA pathway - Physcomitrium patens may possess both pathways. Here, we have characterized the moss ALase as a functional lactonase and evaluated the ascorbate biosynthesis capability of the two pathways using knockout mutants. Physcomitrium patens expresses two ALase paralogs, namely PpALase1 and PpALase2. Kinetic analyses with recombinant enzymes indicated that PpALase1 is a functional enzyme catalyzing the conversion of l-galactonic acid to the final precursor l-galactono-1,4-lactone and that it also reacts with dehydroascorbate as a substrate. Interestingly, mutants lacking PpALase1 (Δal1) showed 1.2-fold higher total ascorbate content than the wild type, and their dehydroascorbate content was increased by 50% compared with that of the wild type. In contrast, the total ascorbate content of mutants lacking PpVTC2-1 (Δvtc2-1) or PpVTC2-2 (Δvtc2-2), which encode the rate-limiting enzyme GDP-l-Gal phosphorylase in the d-Man/l-Gal pathway, was markedly decreased to 46 and 17%, respectively, compared with that of the wild type. Taken together, the dominant ascorbate biosynthetic pathway in P. patens is the d-Man/l-Gal pathway, not the d-GalUA pathway, and PpALase1 may play a significant role in ascorbate metabolism by facilitating dehydroascorbate degradation rather than ascorbate biosynthesis.
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Affiliation(s)
- Tsubasa Sodeyama
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Hitoshi Nishikawa
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Kenji Harai
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Daiki Takeshima
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Yoshihiro Sawa
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Takanori Maruta
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
| | - Takahiro Ishikawa
- Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, 1060 Nishikawatsu, Matsue, Shimane, 690-8504, Japan
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van Midden KP, Peric T, Klemenčič M. Plant type I metacaspases are proteolytically active proteases despite their hydrophobic nature. FEBS Lett 2021; 595:2237-2247. [PMID: 34318487 DOI: 10.1002/1873-3468.14165] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/19/2021] [Accepted: 07/19/2021] [Indexed: 11/08/2022]
Abstract
Plant metacaspases type I (MCA-Is), the closest structural homologs of caspases, are key proteases in stress-induced regulated cell death processes in plants. However, no plant MCA-Is have been characterized in vitro to date. Here, we show that only plant MCA-Is contain a highly hydrophobic loop within the C terminus of their p10 domain. When removed, soluble and proteolytically active plant MCA-Is can be designed and recombinantly produced. We show that the activity of MCA-I depends on calcium ions and that removal of the hydrophobic loop does not affect cleavage and covalent binding to its inhibitor SERPIN. This novel approach will finally allow the development of tools to detect and manipulate the activity of these cysteine proteases in vivo and in planta.
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Affiliation(s)
- Katarina Petra van Midden
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
| | - Tanja Peric
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
| | - Marina Klemenčič
- Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Slovenia
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12
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Cell Death and Metabolic Stress in Gymnodinium catenatum Induced by Allelopathy. Toxins (Basel) 2021; 13:toxins13070506. [PMID: 34357978 PMCID: PMC8310274 DOI: 10.3390/toxins13070506] [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: 05/25/2021] [Revised: 07/05/2021] [Accepted: 07/08/2021] [Indexed: 12/21/2022] Open
Abstract
Allelopathy between phytoplankton species can promote cellular stress and programmed cell death (PCD). The raphidophyte Chattonella marina var. marina, and the dinoflagellates Margalefidinium polykrikoides and Gymnodinium impudicum have allelopathic effects on Gymnodinium catenatum; however, the physiological mechanisms are unknown. We evaluated whether the allelopathic effect promotes cellular stress and activates PCD in G. catenatum. Cultures of G. catenatum were exposed to cell-free media of C. marina var. marina, M. polykrikoides and G. impudicum. The mortality, superoxide radical (O2●-) production, thiobarbituric acid reactive substances (TBARS) levels, superoxide dismutase (SOD) activity, protein content, and caspase-3 activity were quantified. Mortality (between 57 and 79%) was registered in G. catenatum after exposure to cell-free media of the three species. The maximal O2●- production occurred with C. marina var. marina cell-free media. The highest TBARS levels and SOD activity in G. catenatum were recorded with cell-free media from G. impudicum. The highest protein content was recorded with cell-free media from M. polykrikoides. All cell-free media caused an increase in the activity of caspase-3. These results indicate that the allelopathic effect in G. catenatum promotes cell stress and caspase-3 activation, as a signal for the induction of programmed cell death.
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13
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Sukenik A, Kaplan A. Cyanobacterial Harmful Algal Blooms in Aquatic Ecosystems: A Comprehensive Outlook on Current and Emerging Mitigation and Control Approaches. Microorganisms 2021; 9:1472. [PMID: 34361909 PMCID: PMC8306311 DOI: 10.3390/microorganisms9071472] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 12/31/2022] Open
Abstract
An intensification of toxic cyanobacteria blooms has occurred over the last three decades, severely affecting coastal and lake water quality in many parts of the world. Extensive research is being conducted in an attempt to gain a better understanding of the driving forces that alter the ecological balance in water bodies and of the biological role of the secondary metabolites, toxins included, produced by the cyanobacteria. In the long-term, such knowledge may help to develop the needed procedures to restore the phytoplankton community to the pre-toxic blooms era. In the short-term, the mission of the scientific community is to develop novel approaches to mitigate the blooms and thereby restore the ability of affected communities to enjoy coastal and lake waters. Here, we critically review some of the recently proposed, currently leading, and potentially emerging mitigation approaches in-lake novel methodologies and applications relevant to drinking-water treatment.
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Affiliation(s)
- Assaf Sukenik
- The Yigal Allon Kinneret Limnological Laboratory, Israel Oceanographic and Limnological Research, P.O. Box 447, Migdal 14950, Israel
| | - Aaron Kaplan
- Department of Plant and Environmental Sciences, Edmond J. Safra Campus, The Hebrew University of Jerusalem, Givat Ram, Jerusalem 9190401, Israel;
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14
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Expósito JR, Mejuto I, Catalá M. Detection of active cell death markers in rehydrated lichen thalli and the involvement of nitrogen monoxide (NO). Symbiosis 2020. [DOI: 10.1007/s13199-020-00727-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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Treves H, Siemiatkowska B, Luzarowska U, Murik O, Fernandez-Pozo N, Moraes TA, Erban A, Armbruster U, Brotman Y, Kopka J, Rensing SA, Szymanski J, Stitt M. Multi-omics reveals mechanisms of total resistance to extreme illumination of a desert alga. NATURE PLANTS 2020; 6:1031-1043. [PMID: 32719473 DOI: 10.1038/s41477-020-0729-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 06/24/2020] [Indexed: 05/25/2023]
Abstract
The unparalleled performance of Chlorella ohadii under irradiances of twice full sunlight underlines the gaps in our understanding of how the photosynthetic machinery operates, and what sets its upper functional limit. Rather than succumbing to photodamage under extreme irradiance, unique features of photosystem II function allow C. ohadii to maintain high rates of photosynthesis and growth, accompanied by major changes in composition and cellular structure. This remarkable resilience allowed us to investigate the systems response of photosynthesis and growth to extreme illumination in a metabolically active cell. Using redox proteomics, transcriptomics, metabolomics and lipidomics, we explored the cellular mechanisms that promote dissipation of excess redox energy, protein S-glutathionylation, inorganic carbon concentration, lipid and starch accumulation, and thylakoid stacking. C. ohadii possesses a readily available capacity to utilize a sudden excess of reducing power and carbon for growth and reserve formation, and post-translational redox regulation plays a pivotal role in this rapid response. Frequently the response in C. ohadii deviated from that of model species, reflecting its life history in desert sand crusts. Comparative global and case-specific analyses provided insights into the potential evolutionary role of effective reductant utilization in this extreme resistance of C. ohadii to extreme irradiation.
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Affiliation(s)
- Haim Treves
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany.
| | | | | | - Omer Murik
- Department of Plant & Environmental Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Noe Fernandez-Pozo
- Plant Cell Biology, Department of Biology, University of Marburg, Marburg, Germany
| | | | - Alexander Erban
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Ute Armbruster
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Yariv Brotman
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Joachim Kopka
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
| | - Stefan Andreas Rensing
- Plant Cell Biology, Department of Biology, University of Marburg, Marburg, Germany
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Jedrzej Szymanski
- Department of Network Analysis and Modelling, IPK, Gatersleben, Germany
| | - Mark Stitt
- Max Planck Institute for Molecular Plant Physiology, Potsdam, Germany
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16
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Sun Q, Zhou M, Zuo Z. Toxic mechanism of eucalyptol and β-cyclocitral on Chlamydomonas reinhardtii by inducing programmed cell death. JOURNAL OF HAZARDOUS MATERIALS 2020; 389:121910. [PMID: 31879110 DOI: 10.1016/j.jhazmat.2019.121910] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 12/13/2019] [Accepted: 12/15/2019] [Indexed: 06/10/2023]
Abstract
Eucalyptol and β-cyclocitral are 2 main compounds in cyanobacterial volatile organic compounds and can poison other algae. To uncover the toxic mechanism of the 2 compounds, the cell growth, photosynthetic abilities, H2O2 production, caspase-like activities, nuclear variation and DNA laddering were investigated in Chlamydomonas reinhardtii treated with eucalyptol and β-cyclocitral. Eucalyptol at ≥ 0.1 mM and β-cyclocitral at ≥ 0.05 mM showed toxic effects on C. reinhardtii cells, and 1.2 mM eucalyptol and 0.4 mM β-cyclocitral killed the whole of the cells during 24 h. During the death process, the photosynthetic pigment gradually degraded, and Fv/Fm gradually declined, indicating that the death is not a necrosis due to the gradual disappearance of the physiological process. In the treatments with 1.2 mM eucalyptol and 0.4 mM β-cyclocitral, H2O2 content burst at 10 min and 30 min, respectively. Caspase-9-like and caspase-3-like were activated, and cell nucleuses concentrated firstly and then broke with prolonging the treatment time. Meanwhile, DNA showed laddering after 1 h, and was gradually cleaved by Ca2+-dependent endonucleases to mainly about 100-250 bp fragments. These hallmarks indicated that eucalyptol and β-cyclocitral may poison other algal cells by inducing programmed cell death triggered by the increased H2O2.
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Affiliation(s)
- Qing Sun
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China; School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Min Zhou
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China; School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China
| | - Zhaojiang Zuo
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China; School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou 311300, China.
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17
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Dourmap C, Roque S, Morin A, Caubrière D, Kerdiles M, Béguin K, Perdoux R, Reynoud N, Bourdet L, Audebert PA, Moullec JL, Couée I. Stress signalling dynamics of the mitochondrial electron transport chain and oxidative phosphorylation system in higher plants. ANNALS OF BOTANY 2020; 125:721-736. [PMID: 31711195 PMCID: PMC7182585 DOI: 10.1093/aob/mcz184] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Accepted: 11/07/2019] [Indexed: 05/23/2023]
Abstract
BACKGROUND Mitochondria play a diversity of physiological and metabolic roles under conditions of abiotic or biotic stress. They may be directly subjected to physico-chemical constraints, and they are also involved in integrative responses to environmental stresses through their central position in cell nutrition, respiration, energy balance and biosyntheses. In plant cells, mitochondria present various biochemical peculiarities, such as cyanide-insensitive alternative respiration, and, besides integration with ubiquitous eukaryotic compartments, their functioning must be coupled with plastid functioning. Moreover, given the sessile lifestyle of plants, their relative lack of protective barriers and present threats of climate change, the plant cell is an attractive model to understand the mechanisms of stress/organelle/cell integration in the context of environmental stress responses. SCOPE The involvement of mitochondria in this integration entails a complex network of signalling, which has not been fully elucidated, because of the great diversity of mitochondrial constituents (metabolites, reactive molecular species and structural and regulatory biomolecules) that are linked to stress signalling pathways. The present review analyses the complexity of stress signalling connexions that are related to the mitochondrial electron transport chain and oxidative phosphorylation system, and how they can be involved in stress perception and transduction, signal amplification or cell stress response modulation. CONCLUSIONS Plant mitochondria are endowed with a diversity of multi-directional hubs of stress signalling that lead to regulatory loops and regulatory rheostats, whose functioning can amplify and diversify some signals or, conversely, dampen and reduce other signals. Involvement in a wide range of abiotic and biotic responses also implies that mitochondrial stress signalling could result in synergistic or conflicting outcomes during acclimation to multiple and complex stresses, such as those arising from climate change.
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Affiliation(s)
- Corentin Dourmap
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Solène Roque
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Amélie Morin
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Damien Caubrière
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Margaux Kerdiles
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
- Université de Rennes 1, CNRS ECOBIO (Ecosystems-Biodiversity-Evolution) – UMR 6553, Rennes, France
| | - Kyllian Béguin
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
- Université de Rennes 1, CNRS ECOBIO (Ecosystems-Biodiversity-Evolution) – UMR 6553, Rennes, France
| | - Romain Perdoux
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Nicolas Reynoud
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Lucile Bourdet
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Pierre-Alexandre Audebert
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Julien Le Moullec
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
| | - Ivan Couée
- Université de Rennes 1, Department of Life Sciences and Environment, Campus de Beaulieu, Rennes, France
- Université de Rennes 1, CNRS ECOBIO (Ecosystems-Biodiversity-Evolution) – UMR 6553, Rennes, France
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18
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Kuo EY, Chang HL, Lin ST, Lee TM. High Light-Induced Nitric Oxide Production Induces Autophagy and Cell Death in Chlamydomonas reinhardtii. FRONTIERS IN PLANT SCIENCE 2020; 11:772. [PMID: 32587598 PMCID: PMC7298128 DOI: 10.3389/fpls.2020.00772] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 05/15/2020] [Indexed: 05/05/2023]
Abstract
Autophagy plays a role in regulating important cellular functions in response to stress conditions. The role of nitric oxide (NO) in the regulation of autophagy in Chlamydomonas reinhardtii has been not studied. Illumination of C. reinhardtii cells under a high light (HL, 1,600 μmol m-2 s-1) condition induced a NO burst through NO synthase- and nitrate reductase-independent routes, and cell death. The abundance of CrATG8 protein, an autophagy marker of C. reinhardtii, increased after HL illumination along with a linear increase in the transcript abundance of autophagy-associated genes (CrVPS34, CrATG1, CrATG3, CrATG4, CrATG6, CrATG7, CrATG8, and CrATG12), which were suppressed in the presence of an NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). The cells were treated with NO donors, S-nitroso-N-acetyl-penicillamine, and S-nitrosoglutathione, under a normal light (50 μmol m-2 s-1) condition to elucidate the role of NO in autophagy activation and cell death. Treatment with 0.05 mM or 0.1 mM NO donors increased the abundance of ATG8 protein and CrATG transcripts, which were suppressed in the presence of cPTIO. Moreover, treatment with 0.05 mM NO donors did not affect cell viability, while 0.1 mM NO donors elicited a transient decrease in cell growth and death that recovered after 12 h. The transient effect could be prevented by the presence of cPTIO. However, treatment with 1 mM H2O2 and 0.1 mM NO donors enhanced autophagy induction and resulted in cell death after 24 h. The interaction of H2O2 and NO can be prevented by cPTIO treatment. This implies that NO is critical for the interaction of H2O2 and NO that induces cell death and autophagy. Furthermore, exposure to 0.1 mM NO donors under a non-lethal HL condition (750 μmol m-2 s-1) evoked autophagy and cell death. In conclusion, the present findings demonstrated that the NO-mediated autophagy pathway is activated in C. reinhardtii under lethal high intensity illumination and may interact with H2O2 for HL-induced cell death. The relationships between autophagy and cell death are discussed.
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Affiliation(s)
- Eva YuHua Kuo
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Hsueh-Ling Chang
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Shu-Tseng Lin
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Tse-Min Lee
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung, Taiwan
- *Correspondence: Tse-Min Lee,
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19
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de Carpentier F, Lemaire SD, Danon A. When Unity Is Strength: The Strategies Used by Chlamydomonas to Survive Environmental Stresses. Cells 2019; 8:E1307. [PMID: 31652831 PMCID: PMC6912462 DOI: 10.3390/cells8111307] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/18/2019] [Accepted: 10/21/2019] [Indexed: 12/21/2022] Open
Abstract
The unicellular green alga Chlamydomonas reinhardtii is a valuable model system to study a wide spectrum of scientific fields, including responses to environmental conditions. Most studies are performed under optimal growth conditions or under mild stress. However, when environmental conditions become harsher, the behavior of this unicellular alga is less well known. In this review we will show that despite being a unicellular organism, Chlamydomonas can survive very severe environmental conditions. To do so, and depending on the intensity of the stress, the strategies used by Chlamydomonas can range from acclimation to the formation of multicellular structures, or involve programmed cell death.
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Affiliation(s)
- Félix de Carpentier
- Institut de Biologie Physico-Chimique, UMR 8226, CNRS, Sorbonne Université, 75005 Paris, France.
- Faculty of Sciences, Doctoral School of Plant Sciences, Université Paris-Sud, Paris-Saclay, 91400 Orsay, France.
| | - Stéphane D Lemaire
- Institut de Biologie Physico-Chimique, UMR 8226, CNRS, Sorbonne Université, 75005 Paris, France.
| | - Antoine Danon
- Institut de Biologie Physico-Chimique, UMR 8226, CNRS, Sorbonne Université, 75005 Paris, France.
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20
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Daniel E, Weiss G, Murik O, Sukenik A, Lieman-Hurwitz J, Kaplan A. The response of Microcystis aeruginosa strain MGK to a single or two consecutive H 2 O 2 applications. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:621-629. [PMID: 31390482 DOI: 10.1111/1758-2229.12789] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 07/15/2019] [Accepted: 08/05/2019] [Indexed: 06/10/2023]
Abstract
Various approaches have been proposed to control/eliminate toxic Microcystis sp. blooms including H2 O2 treatments. Earlier studies showed that pre-exposure of various algae to oxidative stress induced massive cell death when cultures were exposed to an additional H2 O2 treatment. We examined the vulnerability of exponential and stationary-phase Microcystis sp. strain MGK cultures to single and double H2 O2 applications. Stationary cultures show a much higher ability to decompose H2 O2 than younger cultures. Nevertheless, they are more sensitive to an additional H2 O2 dose given 1-6 h after the first one. Transcript analyses following H2 O2 application showed a fast rise in glutathione peroxidase abundance (227-fold within an hour) followed by a steep decline thereafter. Other genes potentially engaged in oxidative stress were far less affected. Metabolic-related genes were downregulated after H2 O2 treatments. Among those examined, the transcript level of prk (encoding phosphoribulose kinase) was the slowest to recover in agreement with the decline in photosynthetic rate revealed by fluorescence measurements. Our findings shed light on the response of Microcystis MGK to oxidative stress suggesting that two consecutive H2 O2 applications of low concentrations are far more effective in controlling Microcystis sp. population than a single dose of a higher concentration.
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Affiliation(s)
- Einat Daniel
- Plants and Environmental Sciences, the Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 9190401, Israel
| | - Gad Weiss
- Plants and Environmental Sciences, the Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 9190401, Israel
| | - Omer Murik
- The Yigal Allon Kinneret Limnological Laboratory, Israel Oceanographic and Limnological Research, Migdal, Israel
| | - Assaf Sukenik
- The Yigal Allon Kinneret Limnological Laboratory, Israel Oceanographic and Limnological Research, Migdal, Israel
| | - Judy Lieman-Hurwitz
- Plants and Environmental Sciences, the Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 9190401, Israel
| | - Aaron Kaplan
- Plants and Environmental Sciences, the Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 9190401, Israel
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21
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Sadhasivam G, Gelber C, Zakin V, Margel S, Shapiro OH. N-Halamine Derivatized Nanoparticles with Selective Cyanocidal Activity: Potential for Targeted Elimination of Harmful Cyanobacterial Blooms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:9160-9170. [PMID: 31328506 DOI: 10.1021/acs.est.9b01368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Harmful cyanobacterial blooms (HCBs) are becoming a major challenge for the management of both natural and man-made freshwater lakes and reservoirs. Phytoplankton communities are an essential component of aquatic ecosystems, providing the basis for natural food webs as well as important environmental services. HCBs, driven by a combination of environmental pollution and rising global temperatures, destabilize phytoplankton communities with major impacts on aquatic ecology and trophic interactions. Application of currently available algaecides generally results in unselective elimination of phytoplankton species, disrupting water ecology and environmental services provided by beneficial algae. There is thus a need for selective cyanocidal compounds that can eliminate cyanobacteria while preserving algal members of the phytoplankton community. Here, we demonstrate the efficacy of N-halamine derivatized nanoparticles (Cl NPs) in selectively eliminating cyanobacteria, including the universal bloom-forming species Microcystis aeruginosa, while having minimal effect on co-occurring algal species. We further support these results with the use a simple microfluidic platform in combination with advanced live-imaging microscopy to study the effects of Cl NPs on both laboratory cultures and natural populations of cyanobacteria and algae at single cell resolutions. We note that the Cl NPs used in this work were made of polymethacrylamide, a nonbiodegradable polymer that may be unsuitable for use as a cyanocide in open aquatic environments. Nevertheless, the demonstrated selective action of these Cl NPs suggests a potential for developing alternative, biodegradable carriers with similar properties as future cyanocidal agents that will enable selective elimination of HCBs.
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Affiliation(s)
- Giji Sadhasivam
- Department of Food Science, Institute of Postharvest and Food Sciences , Agricultural Research Organization, The Volcani Center , Rishon LeZion 7528809 , Israel
| | - Chen Gelber
- Department of Chemistry, The Institute of Nanotechnology and Advanced Materials , Bar-Ilan University , Ramat-Gan 52900 , Israel
| | - Varda Zakin
- Department of Food Science, Institute of Postharvest and Food Sciences , Agricultural Research Organization, The Volcani Center , Rishon LeZion 7528809 , Israel
| | - Shlomo Margel
- Department of Chemistry, The Institute of Nanotechnology and Advanced Materials , Bar-Ilan University , Ramat-Gan 52900 , Israel
| | - Orr H Shapiro
- Department of Food Science, Institute of Postharvest and Food Sciences , Agricultural Research Organization, The Volcani Center , Rishon LeZion 7528809 , Israel
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22
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Mizrachi A, Graff van Creveld S, Shapiro OH, Rosenwasser S, Vardi A. Light-dependent single-cell heterogeneity in the chloroplast redox state regulates cell fate in a marine diatom. eLife 2019; 8:47732. [PMID: 31232691 PMCID: PMC6682412 DOI: 10.7554/elife.47732] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 06/18/2019] [Indexed: 12/14/2022] Open
Abstract
Diatoms are photosynthetic microorganisms of great ecological and biogeochemical importance, forming vast blooms in aquatic ecosystems. However, we are still lacking fundamental understanding of how individual cells sense and respond to diverse stress conditions, and what acclimation strategies are employed during bloom dynamics. We investigated cellular responses to environmental stress at the single-cell level using the redox sensor roGFP targeted to various organelles in the diatom Phaeodactylum tricornutum. We detected cell-to-cell variability using flow cytometry cell sorting and a microfluidics system for live imaging of oxidation dynamics. Chloroplast-targeted roGFP exhibited a light-dependent, bi-stable oxidation pattern in response to H2O2 and high light, revealing distinct subpopulations of sensitive oxidized cells and resilient reduced cells. Early oxidation in the chloroplast preceded commitment to cell death, and can be used for sensing stress cues and regulating cell fate. We propose that light-dependent metabolic heterogeneity regulates diatoms’ sensitivity to environmental stressors in the ocean. Microscopic algae, such as diatoms, are widely spread throughout the oceans, and are responsible for half of the oxygen we breathe. At certain times of the year these algae grow very rapidly to form large “blooms” that can be detected by satellites in space. These blooms are generally short-lived because the algae are either eaten by other marine organisms, run out of nutrients, or die as a result of being infected by viruses or bacteria. However, some diatom cells survive the end of the bloom and go on to generate new blooms in the future, but it is still not clear how. As the bloom collapses, diatoms experience many stressful conditions which can cause active molecules known as reactive oxygen species, or ROS for short, to accumulate inside cells. Normally growing cells also produce low amounts of ROS, which regulate various processes that are important for maintaining a cell’s health. However, high amounts of ROS can cause damage, which may lead to a cell’s death. Now, Mizrachi et al. investigated why some algae survive while others die in response to stressful conditions, focusing on the amount of ROS that accumulates within the diatom Phaeodactylum tricornutum. Laboratory experiments showed that individual cells of P. tricornutum respond differently to environmental stress, forming two distinct groups of either sensitive or resilient cells. Sensitive cells accumulated high levels of ROS within a cell compartment known as the chloroplast and eventually died. Whereas resilient cells were able to maintain low levels of ROS in the chloroplast and survived long after the other cells perished. Populations of genetically identical diatom cells also formed distinct groups of sensitive and resilient cells, demonstrating that these two opposing reactions to stress are not caused by genetic differences between cells. Lastly, Mizrachi et al. showed that how diatoms acclimate to stress depends on the amount of light they are exposed to. When in the dark, all cells became sensitive to oxidative stress, without forming distinct groups. But, when exposed to strong light that mimics the ocean surface, cells formed distinct groups within the population. This suggests that light regulates how susceptible these microscopic algae are to environmental stress. The different responses within a population may serve as a “bet-hedging” strategy, enabling at least some of the cells to survive unpredicted stressful conditions. The next challenge will be to find out whether algae growing in the oceans also use the same strategy and investigate what impact this has on diatom blooms.
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Affiliation(s)
- Avia Mizrachi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shiri Graff van Creveld
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Orr H Shapiro
- Department of Food Quality and Safety, Institute of Postharvest and Food Sciences, Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
| | - Shilo Rosenwasser
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel.,The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
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Issawi M, Leroy-Lhez S, Sol V, Riou C. Crossing the First Threshold: New Insights into the Influence of the Chemical Structure of Anionic Porphyrins on Plant Cell Wall Interactions and Photodynamic Cell Death Induction. Biochemistry 2019; 58:2188-2197. [PMID: 30942568 DOI: 10.1021/acs.biochem.9b00107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In this study, our fundamental research interest was to understand how negatively charged porphyrins could interact with a plant cell wall and further act inside cells. Thus, three anionic porphyrins differing in their anionic external groups (carboxylates, sulfonates, and phosphonates) were tested. First, the tobacco cell wall was isolated to monitor in vitro its interactions with the three different anionic porphyrins. Unexpectedly, these negatively charged molecules were able to bind to the negatively charged cell wall probably by weak bonds such as hydrogen bonds and/or electrostatic interactions when the tetrapyrrolic core was protonated. Moreover, we showed that at the pH of spent culture medium (4.5), the neutrality of the carboxylated porphyrin (TPPC) facilitated its cell wall crossing while the diffusion of the two other sulfonated (TPPS) or phosphonated (TPPP) porphyrins that remained anionic was delayed. Once inside Tobacco Bright Yellow-2 (TBY-2) cells, TPPC induced higher levels of production of both H2O2 and malondialdehyde compared to TPPS after illumination. That result correlated well with strong cell death induction by photoactivated TPPC. Furthermore, reactive oxygen species-scavenging enzymes such as catalase, peroxidases, and superoxide dismutase were also strongly downmodulated in response to TPPC, while these enzymes were almost unchanged in response to photoactivated TPPS. To the best of our knowledge, this is the first study that took into account the whole story from interactions of porphyrins with a plant cell wall to their photodynamic activity inside the cells.
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Affiliation(s)
- Mohammad Issawi
- Laboratoire Peirene EA7500 , 123 avenue Albert Thomas , 87060 Limoges Cedex, France
| | - Stephanie Leroy-Lhez
- Laboratoire Peirene EA7500 , 123 avenue Albert Thomas , 87060 Limoges Cedex, France
| | - Vincent Sol
- Laboratoire Peirene EA7500 , 123 avenue Albert Thomas , 87060 Limoges Cedex, France
| | - Catherine Riou
- Laboratoire Peirene EA7500 , 123 avenue Albert Thomas , 87060 Limoges Cedex, France
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24
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Murik O, Tirichine L, Prihoda J, Thomas Y, Araújo WL, Allen AE, Fernie AR, Bowler C. Downregulation of mitochondrial alternative oxidase affects chloroplast function, redox status and stress response in a marine diatom. THE NEW PHYTOLOGIST 2019; 221:1303-1316. [PMID: 30216452 DOI: 10.1111/nph.15479] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/03/2018] [Indexed: 05/20/2023]
Abstract
Diatom dominance in contemporary aquatic environments indicates that they have developed unique and effective mechanisms to cope with the rapid and considerable fluctuations that characterize these environments. In view of their evolutionary history from a secondary endosymbiosis, inter-organellar regulation of biochemical activities may be of particular relevance. Diatom mitochondrial alternative oxidase (AOX) is believed to play a significant role in supplying chloroplasts with ATP produced in the mitochondria. Using the model diatom Phaeodactylum tricornutum we generated AOX knockdown lines, and followed sensitivity to stressors, photosynthesis and transcriptome and metabolome profiles of wild-type and knockdown lines. We show here that expression of the AOX gene is upregulated by various stresses including H2 O2 , heat, high light illumination, and iron or nitrogen limitation. AOX knockdown results in hypersensitivity to stress. Knockdown lines also show significantly reduced photosynthetic rates and their chloroplasts are more oxidized. Comparisons of transcriptome and metabolome profiles suggest a strong impact of AOX activity on gene expression, which is carried through to the level of the metabolome. Our data provide evidence for the involvement of mitochondrial AOX in processes central to the cell biology of diatoms, revealing that cross-talk between mitochondria and chloroplasts is crucial for maintaining sensitivity to changing environments.
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Affiliation(s)
- Omer Murik
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, Université PSL, 75005, Paris, France
| | - Leila Tirichine
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, Université PSL, 75005, Paris, France
| | - Judit Prihoda
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, Université PSL, 75005, Paris, France
| | - Yann Thomas
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, Université PSL, 75005, Paris, France
| | - Wagner L Araújo
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
| | - Andrew E Allen
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA
- Integrative Oceanography Division, Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, 92037, USA
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam-Golm, Germany
| | - Chris Bowler
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, Université PSL, 75005, Paris, France
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25
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MDH and CAT increase the germination of cryopreserved Paeonia pollen by regulating the ROS and apoptosis-like events. ACTA ACUST UNITED AC 2019. [DOI: 10.17660/actahortic.2019.1234.13] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Chen Y, Weng Y, Zhou M, Meng Y, Liu J, Yang L, Zuo Z. Linalool- and α-terpineol-induced programmed cell death in Chlamydomonas reinhardtii. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 167:435-440. [PMID: 30368137 DOI: 10.1016/j.ecoenv.2018.10.062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 10/14/2018] [Accepted: 10/16/2018] [Indexed: 06/08/2023]
Abstract
Plant allelochemicals effectively inhibit and/ or control algal growth, and have potential to use as algaecide. To uncover the lethal mechanism of 2 anti-algal compounds linalool and α-terpineol identified from Cinnamomum camphora extracts, and promote their development as algaecide, the H2O2 production, photosynthetic abilities, caspase-like activities, nuclear changes and DNA degradation were investigated in Chlamydomonas reinhardtii treated with the 2 compounds. H2O2 content burst in linalool treatment at 0.5 h and in α-terpineol treatment at 1 h, with increases of 2.7 folds and 1.3 folds, respectively, compared to that at 0 h. The photosynthetic pigments gradually degraded, and Fv/Fm gradually declined to zero, indicating that the cell death was not a necrosis due to the gradual disappearance of physiological process. In C. reinhardtii cells, the caspase-9-like and caspase-3-like were activated in the treatments with the 2 compounds for 1 h. With prolonging the treatment time, the fluorescent intensity of the cell nucleuses stained by DAPI gradually enhanced and then faded, and the genomic DNA isolated from the cells gradually degraded. These hallmarks indicated that the death of C. reinhardtii cells in linalool and α-terpineol treatments was a programmed cell death (PCD) triggered by the increased reactive oxygen species (ROS). Compared to α-terpineol treatment, linalool treatment showed stronger promoting effects on PCD at the same time point, which may be caused by the higher ROS content inducing higher caspase-9-like and caspase-3-like activities in a short time.
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Affiliation(s)
- Yueting Chen
- School of Forestry and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China
| | - Yuanyuan Weng
- School of Forestry and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China
| | - Min Zhou
- School of Forestry and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China
| | - Yiyu Meng
- School of Forestry and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China
| | - Jialu Liu
- School of Forestry and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China
| | - Lin Yang
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Zhaojiang Zuo
- School of Forestry and Biotechnology, Zhejiang A & F University, Hangzhou 311300, China.
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Schieler BM, Soni MV, Brown CM, Coolen MJL, Fredricks H, Van Mooy BAS, Hirsh DJ, Bidle KD. Nitric oxide production and antioxidant function during viral infection of the coccolithophore Emiliania huxleyi. ISME JOURNAL 2019; 13:1019-1031. [PMID: 30607029 PMCID: PMC6461841 DOI: 10.1038/s41396-018-0325-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/14/2018] [Accepted: 11/04/2018] [Indexed: 12/03/2022]
Abstract
Emiliania huxleyi is a globally important marine phytoplankton that is routinely infected by viruses. Understanding the controls on the growth and demise of E. huxleyi blooms is essential for predicting the biogeochemical fate of their organic carbon and nutrients. In this study, we show that the production of nitric oxide (NO), a gaseous, membrane-permeable free radical, is a hallmark of early-stage lytic infection in E. huxleyi by Coccolithoviruses, both in culture and in natural populations in the North Atlantic. Enhanced NO production was detected both intra- and extra-cellularly in laboratory cultures, and treatment of cells with an NO scavenger significantly reduced viral production. Pre-treatment of exponentially growing E. huxleyi cultures with the NO donor S-nitroso-N-acetylpenicillamine (SNAP) prior to challenge with hydrogen peroxide (H2O2) led to greater cell survival, suggesting that NO may have a cellular antioxidant function. Indeed, cell lysates generated from cultures treated with SNAP and undergoing infection displayed enhanced ability to detoxify H2O2. Lastly, we show that fluorescent indicators of cellular ROS, NO, and death, in combination with classic DNA- and lipid-based biomarkers of infection, can function as real-time diagnostic tools to identify and contextualize viral infection in natural E. huxleyi blooms.
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Affiliation(s)
- Brittany M Schieler
- Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ, 08901, USA
| | - Megha V Soni
- Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ, 08901, USA
| | - Christopher M Brown
- Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ, 08901, USA
| | - Marco J L Coolen
- WA-Organic and Isotope Geochemistry Center, School of Earth and Planetary Sciences, Curtin University, Bentley, WA, 6102, Australia
| | - Helen Fredricks
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Benjamin A S Van Mooy
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Donald J Hirsh
- Department of Chemistry, The College of New Jersey, Ewing, NJ, 08628, USA
| | - Kay D Bidle
- Department of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ, 08901, USA.
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28
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Pokora W, Aksmann A, Baścik-Remisiewicz A, Dettlaff-Pokora A, Tukaj Z. Exogenously applied hydrogen peroxide modifies the course of the Chlamydomonas reinhardtii cell cycle. JOURNAL OF PLANT PHYSIOLOGY 2018; 230:61-72. [PMID: 30170242 DOI: 10.1016/j.jplph.2018.07.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 07/09/2018] [Accepted: 07/31/2018] [Indexed: 06/08/2023]
Abstract
The interaction of NO and H2O2 in the regulation of plant development is well documented. We have recently shown that the content of NO and H2O2 changes in a characteristic way during the cell cycle of Chlamydomonas reinhardtii (Pokora et al., 2017), which implies participation of these molecules in the regulation of Chlamydomonas development. To verify this assumption, H2O2 was supplied at a concentration about 1.5 times higher than that determined in the control cells. Cells were synchronized by alternating the light/dark (10/14 h) regimen. H2O2 was added to zoospore suspensions, previously held in the dark, and cells growing for 3, 6, and 9 h in the light. The data indicate that, depending on the phase of the Chlamydomonas cell cycle, H2O2, via mild modification of redox homeostasis, may: a) accelerate or delay the duration of the cell cycle; b) increase the number of replication rounds occurring in one cell cycle; c) modify the biomass and cell volume of progeny cells and d) accelerate the liberation of daughter cells. This provides a tool to control the development of Chlamydomonas cell and thus offers the opportunity to obtain a population of cells with characteristics desired in biotechnology.
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Affiliation(s)
- Wojciech Pokora
- Department of Plant Physiology and Biotechnology, Faculty of Biology, University of Gdańsk, ul. Wita Stwosza 59, 80-308 Gdańsk, Poland.
| | - Anna Aksmann
- Department of Plant Physiology and Biotechnology, Faculty of Biology, University of Gdańsk, ul. Wita Stwosza 59, 80-308 Gdańsk, Poland
| | - Agnieszka Baścik-Remisiewicz
- Department of Plant Physiology and Biotechnology, Faculty of Biology, University of Gdańsk, ul. Wita Stwosza 59, 80-308 Gdańsk, Poland
| | | | - Zbigniew Tukaj
- Department of Plant Physiology and Biotechnology, Faculty of Biology, University of Gdańsk, ul. Wita Stwosza 59, 80-308 Gdańsk, Poland
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29
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Larosa V, Remacle C. Insights into the respiratory chain and oxidative stress. Biosci Rep 2018; 38:BSR20171492. [PMID: 30201689 PMCID: PMC6167499 DOI: 10.1042/bsr20171492] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 08/15/2018] [Accepted: 09/05/2018] [Indexed: 01/13/2023] Open
Abstract
Reactive oxygen species (ROS) are highly reactive reduced oxygen molecules that result from aerobic metabolism. The common forms are the superoxide anion (O2∙-) and hydrogen peroxide (H2O2) and their derived forms, hydroxyl radical (HO∙) and hydroperoxyl radical (HOO∙). Their production sites in mitochondria are reviewed. Even though being highly toxic products, ROS seem important in transducing information from dysfunctional mitochondria. Evidences of signal transduction mediated by ROS in mitochondrial deficiency contexts are then presented in different organisms such as yeast, mammals or photosynthetic organisms.
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Affiliation(s)
- Véronique Larosa
- Genetics and Physiology of Microalgae, UR InBios/Phytosystems, Chemin de la Vallée, 4, University of Liège, Liège 4000, Belgium
| | - Claire Remacle
- Genetics and Physiology of Microalgae, UR InBios/Phytosystems, Chemin de la Vallée, 4, University of Liège, Liège 4000, Belgium
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30
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Liu Z, Shi X, Li S, Zhang L, Song X. Oxidative Stress and Aberrant Programmed Cell Death Are Associated With Pollen Abortion in Isonuclear Alloplasmic Male-Sterile Wheat. FRONTIERS IN PLANT SCIENCE 2018; 9:595. [PMID: 29780399 PMCID: PMC5945952 DOI: 10.3389/fpls.2018.00595] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 04/16/2018] [Indexed: 05/18/2023]
Abstract
Cytoplasmic male sterility is crucial for the utilization of hybrid heterosis and it possibly occurs in parallel with tapetal programmed cell death (PCD) and oxidative metabolism responses. However, little is known about the mechanisms that underlie pollen abortion in wheat. Therefore, we obtained two isonuclear alloplasmic male sterile lines (IAMSLs) with Aegilops kotschyi and Ae. juvenalis cytoplasm. Compared with the maintainer line, cytochemical analyses of the anthers demonstrated that the IAMSLs exhibited anomalous tapetal PCD and organelles, with premature PCD in K87B1-706A and delayed PCD in Ju87B1-706A. We also found that the dynamic trends in reactive oxygen species (ROS) were consistent in these two IAMSLs during anther development and they were potentially associated with the initiation of tapetal PCD. In addition, the activities of ROS-scavenging enzymes increased rapidly, whereas non-enzymatic antioxidants were downregulated together with excess ROS production in IAMSLs. Real-time PCR analysis showed that the expression levels of superoxide dismutase, catalase, and ascorbate peroxidase genes, which encode important antioxidant enzymes, were significantly upregulated during early pollen development. Thus, we inferred that excessive ROS and the abnormal transcript levels of antioxidant enzyme genes disrupted the balance of the antioxidant system and the presence of excess ROS may have been related to aberrant tapetal PCD progression, thereby affecting the development of microspores and ultimately causing male sterility. These relationships between the mechanism of PCD and ROS metabolism provide new insights into the mechanisms responsible for abortive pollen in wheat.
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Affiliation(s)
| | | | | | | | - Xiyue Song
- College of Agronomy, Northwest A&F University, Yangling, China
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31
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Chang HY, Lin ST, Ko TP, Wu SM, Lin TH, Chang YC, Huang KF, Lee TM. Enzymatic characterization and crystal structure analysis of Chlamydomonas reinhardtii dehydroascorbate reductase and their implications for oxidative stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 120:144-155. [PMID: 29028546 DOI: 10.1016/j.plaphy.2017.09.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 09/21/2017] [Accepted: 09/29/2017] [Indexed: 06/07/2023]
Abstract
Dehydroascorbate reductase (DHAR) is a key enzyme for glutathione (GSH)-dependent reduction of dehydroascorbate (DHA) to recycled ascorbate (AsA) in plants, and plays a major role against the toxicity of reactive oxygen species (ROS). Previously, we proposed that the increase of AsA regeneration via enhanced DHAR activity modulates the ascorbate-glutathione cycle activity against photooxidative stress in Chlamydomonas reinhardtii. In the present work, we use site-directed mutagenesis and crystal structure analysis to elucidate the molecular basis of how C. reinhardtii DHAR (CrDHAR1) is involved in the detoxification mechanisms. Mutagenesis data show that the D21A, D21N and C22A mutations result in severe loss of the enzyme's function, suggesting crucial roles of Asp-21 and Cys-22 in substrate binding and catalysis. The mutant K11A also exhibits reduced redox activity (∼50%). The crystal structure of apo CrDHAR1 further provides insights into the proposed mechanism centering on the strictly conserved Cys-22, which is suggested to initiate the redox reactions of DHA and GSH. Furthermore, in vitro oxidation of the recombinant CrDHAR1 in the presence of 1 mM H2O2 has minor effects on the Km for the substrates but significantly reduces the kcat. The enzyme's activity and its mRNA abundance in the C. reinhardtii cells are increased by treatment with 0.2-1 mM H2O2 but decreased when H2O2 is ≥ 1.5 mM. The latter decrease is accompanied by oxidative damage and lower AsA concentrations. These biochemical and physiological data provide new insights into the catalytic mechanism of CrDHAR1, which protects the C. reinhardtii cells from oxidative stress-induced toxicity.
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Affiliation(s)
- Hsin-Yang Chang
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.
| | - Shu-Tseng Lin
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Tzu-Ping Ko
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan
| | - Shu-Mei Wu
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Tsen-Hung Lin
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Yu-Ching Chang
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Kai-Fa Huang
- Institute of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan
| | - Tse-Min Lee
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan; Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.
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32
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González-Pleiter M, Rioboo C, Reguera M, Abreu I, Leganés F, Cid Á, Fernández-Piñas F. Calcium mediates the cellular response of Chlamydomonas reinhardtii to the emerging aquatic pollutant Triclosan. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2017; 186:50-66. [PMID: 28249228 DOI: 10.1016/j.aquatox.2017.02.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/17/2017] [Accepted: 02/19/2017] [Indexed: 06/06/2023]
Abstract
The present study was aimed at investigating the role of intracellular free calcium, [Ca2+]c, in the early cellular response of the green alga Chlamydomonas reinhardtii to the emergent pollutant Triclosan (13.8μM; 24h of exposure). There is a growing concern about the persistence and toxicity of this antimicrobial in aquatic environments, where non-target organisms such as C. reinhardtii, a primary producer of ecological relevance, might be severely impacted. A mechanistic study was undertaken which combined flow cytometry protocols, physiological as well as gene expression analysis. As an early response, Triclosan strongly altered [Ca2+]c homeostasis which could be prevented by prechelation with the intracellular calcium chelator BAPTA-AM. Triclosan induced ROS overproduction which ultimately leads to oxidative stress with loss of membrane integrity, membrane depolarization, photosynthesis inhibition and mitochondrial membrane depolarization; within this context, Triclosan also induced an increase in caspase 3/7 activity and altered the expression of metacaspase genes which are indicative of apoptosis. All these adverse outcomes were dependent on [Ca2+]c. Interestingly, an interconnection between [Ca2+]c alterations and increased ROS formation by Triclosan was found. Taken altogether these results shed light on the mechanisms behind Triclosan toxicity in the green alga Chlamydomonas reinhardtii and demonstrate the role of [Ca2+]c in mediating the observed toxicity.
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Affiliation(s)
- Miguel González-Pleiter
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Carmen Rioboo
- Laboratorio de Microbiología, Facultad de Ciencias, Universidad da Coruña, Campus de A Zapateira s/n, 15008 A Coruña, Spain
| | - María Reguera
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Isidro Abreu
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Francisco Leganés
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Ángeles Cid
- Laboratorio de Microbiología, Facultad de Ciencias, Universidad da Coruña, Campus de A Zapateira s/n, 15008 A Coruña, Spain
| | - Francisca Fernández-Piñas
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
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Vidal-Meireles A, Neupert J, Zsigmond L, Rosado-Souza L, Kovács L, Nagy V, Galambos A, Fernie AR, Bock R, Tóth SZ. Regulation of ascorbate biosynthesis in green algae has evolved to enable rapid stress-induced response via the VTC2 gene encoding GDP-l-galactose phosphorylase. THE NEW PHYTOLOGIST 2017; 214:668-681. [PMID: 28112386 DOI: 10.1111/nph.14425] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 12/04/2016] [Indexed: 05/22/2023]
Abstract
Ascorbate (vitamin C) plays essential roles in stress resistance, development, signaling, hormone biosynthesis and regulation of gene expression; however, little is known about its biosynthesis in algae. In order to provide experimental proof for the operation of the Smirnoff-Wheeler pathway described for higher plants and to gain more information on the regulation of ascorbate biosynthesis in Chlamydomonas reinhardtii, we targeted the VTC2 gene encoding GDP-l-galactose phosphorylase using artificial microRNAs. Ascorbate concentrations in VTC2 amiRNA lines were reduced to 10% showing that GDP-l-galactose phosphorylase plays a pivotal role in ascorbate biosynthesis. The VTC2 amiRNA lines also grow more slowly, have lower chlorophyll content, and are more susceptible to stress than the control strains. We also demonstrate that: expression of the VTC2 gene is rapidly induced by H2 O2 and 1 O2 resulting in a manifold increase in ascorbate content; in contrast to plants, there is no circadian regulation of ascorbate biosynthesis; photosynthesis is not required per se for ascorbate biosynthesis; and Chlamydomonas VTC2 lacks negative feedback regulation by ascorbate in the physiological concentration range. Our work demonstrates that ascorbate biosynthesis is also highly regulated in Chlamydomonas albeit via mechanisms distinct from those previously described in land plants.
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Affiliation(s)
- André Vidal-Meireles
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Juliane Neupert
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Laura Zsigmond
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Laise Rosado-Souza
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - László Kovács
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Valéria Nagy
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Anikó Galambos
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
| | - Alisdair R Fernie
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Ralph Bock
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - Szilvia Z Tóth
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, H-6726, Szeged, Hungary
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Yang DY, Li M, Ma NN, Yang XH, Meng QW. Tomato SlGGP-LIKE gene participates in plant responses to chilling stress and pathogenic infection. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 112:218-226. [PMID: 28092850 DOI: 10.1016/j.plaphy.2017.01.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 12/05/2016] [Accepted: 01/06/2017] [Indexed: 06/06/2023]
Abstract
Plants are always exposed to abiotic and biotic stresses which can adversely affect their growth and development. As an important antioxidant, AsA plays a vital role in plant defence against damage caused by stresses. In this study, we cloned a tomato GDP-L-galactose phosphorylase-like (SlGGP-LIKE) gene and investigated its role in resistance to abiotic and biotic stresses by using antisense transgenic (AS) tomato lines. The AsA content in AS plants was lower than that in WT plants. Under chilling stress, the growth of AS plants was inhibited significantly, and they yielded higher levels of ROS, REC and MDA but demonstrated weaker APX activity than that shown by WT plants. Additionally, the declined values of Pn, Fv/Fm, oxidisable P700, and D1 protein content of PSII in AS lines were significant. Furthermore, the effect on xanthophyll cycle of AS plants was more severe than that on WT plants, and the ratio of zeaxanthin (Z)/(V + A + Z) and (Z + 0.5 A)/(V + A + Z) in AS lines was lower than that in WT plants. In spite of chilling stress, under Pseudomonas syringae pv.tomato (Pst) DC3000 strain infection, AS plants showed lesser bacterial cell growth and dead cells than those shown by WT plants. This finding indicated that AS plants demonstrated stronger resistance against pathogenic infection. Results suggest that SlGGP-LIKE gene played an important role in plant defence against chilling stress and pathogenic infection.
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Affiliation(s)
- Dong-Yue Yang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, 61 Dai Zong Street, Tai'an, Shandong 271018, China
| | - Meng Li
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, 61 Dai Zong Street, Tai'an, Shandong 271018, China
| | - Na-Na Ma
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, 61 Dai Zong Street, Tai'an, Shandong 271018, China
| | - Xing-Hong Yang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, 61 Dai Zong Street, Tai'an, Shandong 271018, China.
| | - Qing-Wei Meng
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, 61 Dai Zong Street, Tai'an, Shandong 271018, China.
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Lin ST, Chiou CW, Chu YL, Hsiao Y, Tseng YF, Chen YC, Chen HJ, Chang HY, Lee TM. Enhanced Ascorbate Regeneration Via Dehydroascorbate Reductase Confers Tolerance to Photo-Oxidative Stress in Chlamydomonas reinhardtii. PLANT & CELL PHYSIOLOGY 2016; 57:2104-2121. [PMID: 27440549 DOI: 10.1093/pcp/pcw129] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 07/12/2016] [Indexed: 05/26/2023]
Abstract
The role of ascorbate (AsA) recycling via dehydroascorbate reductase (DHAR) in the tolerance of Chlamydomonas reinhardtii to photo-oxidative stress was examined. The activity of DHAR and the abundance of the CrDHAR1 (Cre10.g456750) transcript increased after moderate light (ML; 750 µmol m-2 s-1) or high light (HL; 1,800 µmol m-2 s-1) illumination, accompanied by dehydroascorbate (DHA) accumulation, decreased AsA redox state, photo-inhibition, lipid peroxidation, H2O2 overaccumulation, growth inhibition and cell death. It suggests that DHAR and AsA recycling is limiting under high-intensity light stress. The CrDHAR1 gene was cloned and its recombinant CrDHAR1 protein was a monomer (25 kDa) detected by Western blot that exhibits an enzymatic activity of 965 µmol min-1 mg-1 protein. CrDHAR1 was overexpressed driven by a HSP70A:RBCS2 fusion promoter or down-regulated by artificial microRNA (amiRNA) to examine whether DHAR-mediated AsA recycling is critical for the tolerance of C. reinahartii cells to photo-oxidative stress. The overexpression of CrDHAR1 increased DHAR protein abundance and enzyme activity, AsA pool size, AsA:DHA ratio and the tolerance to ML-, HL-, methyl viologen- or H2O2-induced oxidative stress. The CrDHAR1-knockdown amiRNA lines that have lower DHAR expression and AsA recycling ability were sensitive to high-intensity illumination and oxidative stress. The glutathione pool size, glutathione:oxidized glutathione ratio and glutathione reductase and ascorbate peroxidase activities were increased in CrDHAR1-overexpressing cells and showed a further increase after high-intensity illumination but decreased in wild-type cells after light stress. The present results suggest that increasing AsA regeneration via enhanced DHAR activity modulates the ascorbate-glutathione cycle activity in C. reinhardtii against photo-oxidative stress.
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Affiliation(s)
- Shu-Tseng Lin
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- These authors contributed equally to this work
| | - Chih-Wen Chiou
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- These authors contributed equally to this work
| | - Yen-Lin Chu
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Yu Hsiao
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Yu-Fei Tseng
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Yi-Chun Chen
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Hsien-Jung Chen
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Hsin-Yang Chang
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 804, Taiwan
| | - Tse-Min Lee
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 804, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung 804, Taiwan
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Sheyn U, Rosenwasser S, Ben-Dor S, Porat Z, Vardi A. Modulation of host ROS metabolism is essential for viral infection of a bloom-forming coccolithophore in the ocean. THE ISME JOURNAL 2016; 10:1742-54. [PMID: 26784355 PMCID: PMC4918435 DOI: 10.1038/ismej.2015.228] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 10/13/2014] [Accepted: 11/06/2015] [Indexed: 11/09/2022]
Abstract
The cosmopolitan coccolithophore Emiliania huxleyi is a unicellular eukaryotic alga responsible for vast blooms in the ocean. These blooms have immense impact on large biogeochemical cycles and are terminated by a specific large double-stranded DNA E. huxleyi virus (EhV, Phycodnaviridae). EhV infection is accompanied by induction of hallmarks of programmed cell death and production of reactive oxygen species (ROS). Here we characterized alterations in ROS metabolism and explored its role during infection. Transcriptomic analysis of ROS-related genes predicted an increase in glutathione (GSH) and H2O2 production during infection. In accordance, using biochemical assays and specific fluorescent probes we demonstrated the overproduction of GSH during lytic infection. We also showed that H2O2 production, rather than superoxide, is the predominant ROS during the onset of the lytic phase of infection. Using flow cytometry, confocal microscopy and multispectral imaging flow cytometry, we showed that the profound co-production of H2O2 and GSH occurred in the same subpopulation of cells but at different subcellular localization. Positively stained cells for GSH and H2O2 were highly infected compared with negatively stained cells. Inhibition of ROS production by application of a peroxidase inhibitor or an H2O2 scavenger inhibited host cell death and reduced viral production. We conclude that viral infection induced remodeling of the host antioxidant network that is essential for a successful viral replication cycle. This study provides insight into viral replication strategy and suggests the use of specific cellular markers to identify and quantify the extent of active viral infection during E. huxleyi blooms in the ocean.
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Affiliation(s)
- Uri Sheyn
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shilo Rosenwasser
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shifra Ben-Dor
- Department of Biological Services, Weizmann Institute of Science, Rehovot, Israel
| | - Ziv Porat
- Department of Biological Services, Weizmann Institute of Science, Rehovot, Israel
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
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38
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Characterization of salt stress-induced palmelloids in the green alga, Chlamydomonas reinhardtii. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.03.035] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Treves H, Raanan H, Kedem I, Murik O, Keren N, Zer H, Berkowicz SM, Giordano M, Norici A, Shotland Y, Ohad I, Kaplan A. The mechanisms whereby the green alga Chlorella ohadii, isolated from desert soil crust, exhibits unparalleled photodamage resistance. THE NEW PHYTOLOGIST 2016; 210:1229-43. [PMID: 26853530 DOI: 10.1111/nph.13870] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/16/2015] [Indexed: 05/24/2023]
Abstract
Excess illumination damages the photosynthetic apparatus with severe implications with regard to plant productivity. Unlike model organisms, the growth of Chlorella ohadii, isolated from desert soil crust, remains unchanged and photosynthetic O2 evolution increases, even when exposed to irradiation twice that of maximal sunlight. Spectroscopic, biochemical and molecular approaches were applied to uncover the mechanisms involved. D1 protein in photosystem II (PSII) is barely degraded, even when exposed to antibiotics that prevent its replenishment. Measurements of various PSII parameters indicate that this complex functions differently from that in model organisms and suggest that C. ohadii activates a nonradiative electron recombination route which minimizes singlet oxygen formation and the resulting photoinhibition. The light-harvesting antenna is very small and carotene composition is hardly affected by excess illumination. Instead of succumbing to photodamage, C. ohadii activates additional means to dissipate excess light energy. It undergoes major structural, compositional and physiological changes, leading to a large rise in photosynthetic rate, lipids and carbohydrate content and inorganic carbon cycling. The ability of C. ohadii to avoid photodamage relies on a modified function of PSII and the dissipation of excess reductants downstream of the photosynthetic reaction centers. The biotechnological potential as a gene source for crop plant improvement is self-evident.
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Affiliation(s)
- Haim Treves
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Hagai Raanan
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Isaac Kedem
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Omer Murik
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Nir Keren
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Hagit Zer
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Simon M Berkowicz
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Mario Giordano
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, 60131, Italy
| | - Alessandra Norici
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, 60131, Italy
| | - Yoram Shotland
- Department of Chemical Engineering, Shamoon College of Engineering, Beer Sheva, 84100, Israel
| | - Itzhak Ohad
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Aaron Kaplan
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
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Kasuba KC, Vavilala SL, D'Souza JS. Apoptosis-like cell death in unicellular photosynthetic organisms — A review. ALGAL RES 2015. [DOI: 10.1016/j.algal.2015.07.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Van Aken O, Van Breusegem F. Licensed to Kill: Mitochondria, Chloroplasts, and Cell Death. TRENDS IN PLANT SCIENCE 2015; 20:754-766. [PMID: 26442680 DOI: 10.1016/j.tplants.2015.08.002] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 08/03/2015] [Accepted: 08/10/2015] [Indexed: 05/18/2023]
Abstract
Programmed cell death (PCD) is crucial in plant organogenesis and survival. In this review the involvement of mitochondria and chloroplasts in PCD execution is critically assessed. Recent findings support a central role for mitochondria in PCD, with newly identified components of the mitochondrial electron transport chain (mETC), FOF1 ATP synthase, cardiolipins, and ATPase AtOM66. While chloroplasts received less attention, their contribution to PCD is well supported, suggesting that they possibly contribute by producing reactive oxygen species (ROS) in the presence of light or even contribute through cytochrome f release. Finally we discuss two working models where mitochondria and chloroplasts could cooperatively execute PCD: mitochondria initiate the commitment steps and recruit chloroplasts for swift execution or, alternatively, mitochondria and chloroplasts could operate in parallel.
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Affiliation(s)
- Olivier Van Aken
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Australia.
| | - Frank Van Breusegem
- Department of Plant Systems Biology, VIB, Ghent University, B-9052 Gent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Gent, Belgium
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Improving the sunlight-to-biomass conversion efficiency in microalgal biofactories. J Biotechnol 2014; 201:28-42. [PMID: 25160918 DOI: 10.1016/j.jbiotec.2014.08.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 07/31/2014] [Accepted: 08/18/2014] [Indexed: 12/31/2022]
Abstract
Microalgae represent promising organisms for the sustainable production of commodities, chemicals or fuels. Future use of such systems, however, requires increased productivity of microalgal mass cultures in order to reach an economic viability for microalgae-based production schemes. The efficiency of sunlight-to-biomass conversion that can be observed in bulk cultures is generally far lower (35-80%) than the theoretical maximum, because energy losses occur at multiple steps during the light-driven conversion of carbon dioxide to organic carbon. The light-harvesting system is a major source of energy losses and thus a prime target for strain engineering. Truncation of the light-harvesting antenna in the algal model organism Chlamydomonas reinhardtii was shown to be an effective way of increasing culture productivity at least under saturating light conditions. Furthermore engineering of the Calvin-Benson cycle or the creation of photorespiratory bypasses in A. thaliana proved to be successful in terms of achieving higher biomass productivities. An efficient generation of novel microalgal strains with improved sunlight conversion efficiencies by targeted engineering in the future will require an expanded molecular toolkit. In the meantime random mutagenesis coupled to high-throughput screening for desired phenotypes can be used to provide engineered microalgae.
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