1
|
Kharabian-Masouleh A, Furtado A, Alsubaie B, Al-Dossary O, Wu A, Al-Mssalem I, Henry R. Loss of plastid ndh genes in an autotrophic desert plant. Comput Struct Biotechnol J 2023; 21:5016-5027. [PMID: 37867970 PMCID: PMC10589726 DOI: 10.1016/j.csbj.2023.10.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/12/2023] [Accepted: 10/13/2023] [Indexed: 10/24/2023] Open
Abstract
Plant plastid genomes are highly conserved with most flowering plants having the same complement of essential plastid genes. Here, we report the loss of five of the eleven NADH dehydrogenase subunit genes (ndh) in the plastid of a desert plant jojoba (Simmondsia chinensis). The plastid genome of jojoba was 156,496 bp with one large single copy region (LSC), a very small single copy region (SSC) and two expanded inverted repeats (IRA + IRB). The NADH dehydrogenase (NDH) complex is comprised of several protein subunits, encoded by the ndh genes of the plastome and the nucleus. The ndh genes are critical to the proper functioning of the photosynthetic electron transport chain and protection of plants from oxidative stress. Most plants are known to contain all eleven ndh genes. Plants with missing or defective ndh genes are often heterotrophs either due to their complete or holo- or myco- parasitic nature. Plants with a defective NDH complex, caused by the deletion/pseudogenisation of some or all the ndh genes, survive in milder climates suggesting the likely extinction of plant lineages lacking these genes under harsh climates. Interestingly, some autotrophic plants do exist without ndh gene/s and can cope with high or low light. This implies that these plants are protected from oxidative stress by mechanisms excluding ndh genes. Jojoba has evolved mechanisms to cope with a non-functioning NDH complex and survives in extreme desert conditions with abundant sunlight and limited water.
Collapse
Affiliation(s)
- Ardashir Kharabian-Masouleh
- Queensland Alliance for Innovation in Food and Agriculture (QAAFI), The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
- ARC Centre of Excellence for Plant Success in Nature and Agriculture, The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
| | - Agnelo Furtado
- Queensland Alliance for Innovation in Food and Agriculture (QAAFI), The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
| | - Bader Alsubaie
- Queensland Alliance for Innovation in Food and Agriculture (QAAFI), The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
- College of Agriculture and Food Sciences, King Faisal University (KFU), Al Hofuf, 36362 Saudi Arabia
| | - Othman Al-Dossary
- Queensland Alliance for Innovation in Food and Agriculture (QAAFI), The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
- College of Agriculture and Food Sciences, King Faisal University (KFU), Al Hofuf, 36362 Saudi Arabia
| | - Alex Wu
- Queensland Alliance for Innovation in Food and Agriculture (QAAFI), The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
| | - Ibrahim Al-Mssalem
- College of Agriculture and Food Sciences, King Faisal University (KFU), Al Hofuf, 36362 Saudi Arabia
| | - Robert Henry
- Queensland Alliance for Innovation in Food and Agriculture (QAAFI), The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
- ARC Centre of Excellence for Plant Success in Nature and Agriculture, The University of Queensland, Carmody Rd, St Lucia, QLD 4072, Australia
| |
Collapse
|
2
|
Xu YL, Shen HH, Du XY, Lu L. Plastome characteristics and species identification of Chinese medicinal wintergreens ( Gaultheria, Ericaceae). PLANT DIVERSITY 2022; 44:519-529. [PMID: 36540705 PMCID: PMC9751084 DOI: 10.1016/j.pld.2022.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/01/2022] [Accepted: 06/13/2022] [Indexed: 06/17/2023]
Abstract
Wintergreen oil is a folk medicine widely used in foods, pesticides, cosmetics and drugs. In China, nine out of 47 species within Gaultheria (Ericaceae) are traditionally used as Chinese medicinal wintergreens; however, phylogenetic approaches currently used to discriminating these species remain unsatisfactory. In this study, we sequenced and characterized plastomes from nine Chinese wintergreen species and identified candidate DNA barcoding regions for Gaultheria. Each Gaultheria plastome contained 110 unique genes (76 protein-coding, 30 tRNA, and four rRNA genes). Duplication of trnfM, rps14, and rpl23 genes were detected, while all plastomes lacked ycf1 and ycf2 genes. Gaultheria plastomes shared substantially contracted SSC regions that contained only the ndhF gene. Moreover, plastomes of Gaultheria leucocarpa var. yunnanensis contained an inversion in the LSC region and an IR expansion to cover the ndhF gene. Multiple rearrangement events apparently occurred between the Gaultheria plastomes and those from several previously reported families in Ericales. Our phylogenetic reconstruction using 42 plastomes revealed well-supported relationships within all nine Gaultheria species. Additionally, seven mutational hotspot regions were identified as potential DNA barcodes for Chinese medicinal wintergreens. Our study is the first to generate complete plastomes and describe the structural variations of the complicated genus Gaultheria. In addition, our findings provide important resources for identification of Chinese medicinal wintergreens.
Collapse
Affiliation(s)
- Yan-Ling Xu
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan, China
| | - Hao-Hua Shen
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan, China
| | - Xin-Yu Du
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Lu Lu
- School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan, China
| |
Collapse
|
3
|
Sabater B. On the Edge of Dispensability, the Chloroplast ndh Genes. Int J Mol Sci 2021; 22:12505. [PMID: 34830386 PMCID: PMC8621559 DOI: 10.3390/ijms222212505] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/12/2021] [Accepted: 11/17/2021] [Indexed: 11/23/2022] Open
Abstract
The polypeptides encoded by the chloroplast ndh genes and some nuclear genes form the thylakoid NADH dehydrogenase (Ndh) complex, homologous to the mitochondrial complex I. Except for Charophyceae (algae related to higher plants) and a few Prasinophyceae, all eukaryotic algae lack ndh genes. Among vascular plants, the ndh genes are absent in epiphytic and in some species scattered among different genera, families, and orders. The recent identification of many plants lacking plastid ndh genes allows comparison on phylogenetic trees and functional investigations of the ndh genes. The ndh genes protect Angiosperms under various terrestrial stresses, maintaining efficient photosynthesis. On the edge of dispensability, ndh genes provide a test for the natural selection of photosynthesis-related genes in evolution. Variable evolutionary environments place Angiosperms without ndh genes at risk of extinction and, probably, most extant ones may have lost ndh genes recently. Therefore, they are evolutionary endpoints in phylogenetic trees. The low number of sequenced plastid DNA and the long lifespan of some Gymnosperms lacking ndh genes challenge models about the role of ndh genes protecting against stress and promoting leaf senescence. Additional DNA sequencing in Gymnosperms and investigations into the molecular mechanisms of their response to stress will provide a unified model of the evolutionary and functional consequences of the lack of ndh genes.
Collapse
Affiliation(s)
- Bartolomé Sabater
- Department of Life Sciences, University of Alcalá, Alcalá de Henares, 28805 Madrid, Spain
| |
Collapse
|
4
|
Liu H, Able AJ, Able JA. Integrated Analysis of Small RNA, Transcriptome, and Degradome Sequencing Reveals the Water-Deficit and Heat Stress Response Network in Durum Wheat. Int J Mol Sci 2020; 21:ijms21176017. [PMID: 32825615 PMCID: PMC7504575 DOI: 10.3390/ijms21176017] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 11/16/2022] Open
Abstract
Water-deficit and heat stress negatively impact crop production. Mechanisms underlying the response of durum wheat to such stresses are not well understood. With the new durum wheat genome assembly, we conducted the first multi-omics analysis with next-generation sequencing, providing a comprehensive description of the durum wheat small RNAome (sRNAome), mRNA transcriptome, and degradome. Single and combined water-deficit and heat stress were applied to stress-tolerant and -sensitive Australian genotypes to study their response at multiple time-points during reproduction. Analysis of 120 sRNA libraries identified 523 microRNAs (miRNAs), of which 55 were novel. Differentially expressed miRNAs (DEMs) were identified that had significantly altered expression subject to stress type, genotype, and time-point. Transcriptome sequencing identified 49,436 genes, with differentially expressed genes (DEGs) linked to processes associated with hormone homeostasis, photosynthesis, and signaling. With the first durum wheat degradome report, over 100,000 transcript target sites were characterized, and new miRNA-mRNA regulatory pairs were discovered. Integrated omics analysis identified key miRNA-mRNA modules (particularly, novel pairs of miRNAs and transcription factors) with antagonistic regulatory patterns subject to different stresses. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis revealed significant roles in plant growth and stress adaptation. Our research provides novel and fundamental knowledge, at the whole-genome level, for transcriptional and post-transcriptional stress regulation in durum wheat.
Collapse
|
5
|
Maia RA, da Cruz Saraiva KD, Roque ALM, Thiers KLL, Dos Santos CP, da Silva JHM, Feijó DF, Arnholdt-Schmitt B, Costa JH. Differential expression of recently duplicated PTOX genes in Glycine max during plant development and stress conditions. J Bioenerg Biomembr 2019; 51:355-370. [PMID: 31506801 DOI: 10.1007/s10863-019-09810-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 08/29/2019] [Indexed: 12/13/2022]
Abstract
Plastid terminal oxidase (PTOX) is a chloroplast enzyme that catalyzes oxidation of plastoquinol (PQH2) and reduction of molecular oxygen to water. Its function has been associated with carotenoid biosynthesis, chlororespiration and environmental stress responses in plants. In the majority of plant species, a single gene encodes the protein and little is known about events of PTOX gene duplication and their implication to plant metabolism. Previously, two putative PTOX (PTOX1 and 2) genes were identified in Glycine max, but the evolutionary origin and the specific function of each gene was not explored. Phylogenetic analyses revealed that this gene duplication occurred apparently during speciation involving the Glycine genus ancestor, an event absent in all other available plant leguminous genomes. Gene expression evaluated by RT-qPCR and RNA-seq data revealed that both PTOX genes are ubiquitously expressed in G. max tissues, but their mRNA levels varied during development and stress conditions. In development, PTOX1 was predominant in young tissues, while PTOX2 was more expressed in aged tissues. Under stress conditions, the PTOX transcripts varied according to stress severity, i.e., PTOX1 mRNA was prevalent under mild or moderate stresses while PTOX2 was predominant in drastic stresses. Despite the high identity between proteins (97%), molecular docking revealed that PTOX1 has higher affinity to substrate plastoquinol than PTOX2. Overall, our results indicate a functional relevance of this gene duplication in G. max metabolism, whereas PTOX1 could be associated with chloroplast effectiveness and PTOX2 to senescence and/or apoptosis.
Collapse
Affiliation(s)
- Rachel Alves Maia
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
| | - Kátia Daniella da Cruz Saraiva
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
- Federal Institute of Education, Science and Technology of Paraíba - IFPB, Campus Princesa Isabel, 58755-000, BR-426, S/N - Rural Zone, Princesa Isabel, Paraíba, Brazil
| | - André Luiz Maia Roque
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
| | - Karine Leitão Lima Thiers
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
| | - Clesivan Pereira Dos Santos
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
| | | | - Daniel Ferreira Feijó
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
| | - Birgit Arnholdt-Schmitt
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil
- Functional Cell Reprogramming and Organism Plasticity (FunCrop - virtual network), EU Marie Curie Chair, ICAAM, University of Évora, Apartado 94, 7002-554, Évora, Portugal
- Science and Technology Park Alentejo (PACT), 7005-841, Évora, Portugal
| | - José Hélio Costa
- Functional Genomics and Bioinformatics, Department of Biochemistry and Molecular Biology, Federal University of Ceará, Fortaleza, Ceará, 60451-970, Brazil.
- Functional Cell Reprogramming and Organism Plasticity (FunCrop - virtual network), EU Marie Curie Chair, ICAAM, University of Évora, Apartado 94, 7002-554, Évora, Portugal.
| |
Collapse
|
6
|
Li ZQ, Xing W, Luo P, Zhang FJ, Jin XL, Zhang MH. Comparative transcriptome analysis of Rosa chinensis 'Slater's crimson China' provides insights into the crucial factors and signaling pathways in heat stress response. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 142:312-331. [PMID: 31352248 DOI: 10.1016/j.plaphy.2019.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 06/30/2019] [Accepted: 07/01/2019] [Indexed: 06/10/2023]
Abstract
Heat stress limits the growth of roses and adversely affects the yield and the quality of the rose cut-flowers. To investigate the heat stress response (HSR) mechanisms of rose, we compared the transcriptome profiling generated from Rosa chinensis 'Slater's crimson China' exposed to heat stress for five different time duration (0, 0.5, 2, 6, 12 h). Overall, 6175 differentially expressed genes (DGEs) were identified and exhibited different temporal expression patterns. Up-regulated genes related to chaperone-mediated protein folding, signal transduction and ROS scavenging were rapidly induced after 0.5-2 h of heat treatment, which provides evidence for the early adjustments of heat stress response in R. chinensis. While the down-regulated genes related to light reaction, sucrose biosynthesis, starch biosynthesis and cell wall biosynthesis were identified after as short as 6 h of heat stress, which indicated the ongoing negative effects on the physiology of R. chinensis. Using weighted gene co-expression network analysis, we found that different heat stress stages could be delineated by several modules. Based on integrating the transcription factors with upstream enriched DNA motifs of co-expressed genes in these modules, the gene regulation networks were predicted and several regulators of HSR were identified. Of particular importance was the discovery of the module associated with rapid sensing and signal transduction, in which numerous co-expressed genes related to chaperones, Ca2+ signaling pathways and transcription factors were identified. The results of this study provided an important resource for further dissecting the role of candidate genes governing the transcriptional regulatory network of HSR in Rose.
Collapse
Affiliation(s)
- Ze Qing Li
- College of Landscape Architecture, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - Wen Xing
- College of Landscape Architecture, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China.
| | - Ping Luo
- Zhejiang Agriculture and Forestry University, Hangzhou, 311300, Zhejiang, China
| | - Fang Jing Zhang
- College of Landscape Architecture, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - Xiao Ling Jin
- College of Landscape Architecture, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - Min Huan Zhang
- College of Landscape Architecture, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| |
Collapse
|
7
|
Madireddi SK, Nama S, Devadasu E, Subramanyam R. Thylakoid membrane dynamics and state transitions in Chlamydomonas reinhardtii under elevated temperature. PHOTOSYNTHESIS RESEARCH 2019; 139:215-226. [PMID: 30030686 DOI: 10.1007/s11120-018-0562-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Accepted: 07/16/2018] [Indexed: 06/08/2023]
Abstract
Moderately elevated temperatures can induce state transitions in higher plants by phosphorylation of light-harvesting complex II (LHCII). In this study, we exposed unicellular algae Chlamydomonas reinhardtii to moderately elevated temperatures (38 °C) for short period of time in the dark to understand the thylakoid membrane dynamics and state transition mechanism. Here we report that under elevated temperatures (1) LHCII gets phosphorylated similar to higher plants and (2) there is decreased absorption cross section of photosystem II (PSII), whereas (3) there is no change in absorption cross section of photosystem I (PSI) indicating that LHCII trimers are largely disconnected with both photosystems under moderately elevated temperatures and (4) on return to room temperature after elevated temperature treatment there is a formation of state transition complex comprising of PSII-LHCII-PSI. The temperature-induced state transition mechanism also depends on stt7 kinase-like in light-induced state transition. The protein content was stable at the moderately elevated temperature treatment of 40 °C; however, at 45 °C severe downregulation in photosynthetic performance and protein content was observed. In addition to the known changes to photosynthetic apparatus, elevated temperatures can destabilize the PSII-LHCII complex that can result in decreased photosynthetic efficiency in C. reinhardtii. We concluded that the membrane dynamics of light-induced state transitions differs considerably from temperature-induced state transition mechanisms in C. reinhardtii.
Collapse
Affiliation(s)
- Sai Kiran Madireddi
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Srilatha Nama
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Elsinraju Devadasu
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Rajagopal Subramanyam
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India.
| |
Collapse
|
8
|
Zuo C, Tang Y, Fu H, Liu Y, Zhang X, Zhao B, Xu Y. Elucidation and analyses of the regulatory networks of upland and lowland ecotypes of switchgrass in response to drought and salt stresses. PLoS One 2018; 13:e0204426. [PMID: 30248119 PMCID: PMC6152977 DOI: 10.1371/journal.pone.0204426] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 09/09/2018] [Indexed: 02/02/2023] Open
Abstract
Switchgrass is an important bioenergy crop typically grown in marginal lands, where the plants must often deal with abiotic stresses such as drought and salt. Alamo is known to be more tolerant to both stress types than Dacotah, two ecotypes of switchgrass. Understanding of their stress response and adaptation programs can have important implications to engineering more stress tolerant plants. We present here a computational study by analyzing time-course transcriptomic data of the two ecotypes to elucidate and compare their regulatory systems in response to drought and salt stresses. A total of 1,693 genes (target genes or TGs) are found to be differentially expressed and possibly regulated by 143 transcription factors (TFs) in response to drought stress together in the two ecotypes. Similarly, 1,535 TGs regulated by 110 TFs are identified to be involved in response to salt stress. Two regulatory networks are constructed to predict their regulatory relationships. In addition, a time-dependent hidden Markov model is derived for each ecotype responding to each stress type, to provide a dynamic view of how each regulatory network changes its behavior over time. A few new insights about the response mechanisms are predicted from the regulatory networks and the time-dependent models. Comparative analyses between the network models of the two ecotypes reveal key commonalities and main differences between the two regulatory systems. Overall, our results provide new information about the complex regulatory mechanisms of switchgrass responding to drought and salt stresses.
Collapse
Affiliation(s)
- Chunman Zuo
- College of Computer Science and Technology, Jilin University, Changchun, China
- Computational Systems Biology Lab, Department of Biochemistry and Molecular Biology and Institute of Bioinformatics, University of Georgia, Athens, GA, United States of America
| | - Yuhong Tang
- Noble Research Institute, LLC., Ardmore, OK, United States of America
| | - Hao Fu
- North Automatic Control Technology Institute, Taiyuan, China
| | - Yiming Liu
- Department of Crop and Soil Environmental Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Xunzhong Zhang
- Department of Crop and Soil Environmental Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Bingyu Zhao
- Department of Horticulture, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Ying Xu
- College of Computer Science and Technology, Jilin University, Changchun, China
- Computational Systems Biology Lab, Department of Biochemistry and Molecular Biology and Institute of Bioinformatics, University of Georgia, Athens, GA, United States of America
| |
Collapse
|
9
|
Ivanov AG, Velitchkova MY, Allakhverdiev SI, Huner NPA. Heat stress-induced effects of photosystem I: an overview of structural and functional responses. PHOTOSYNTHESIS RESEARCH 2017; 133:17-30. [PMID: 28391379 DOI: 10.1007/s11120-017-0383-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 04/03/2017] [Indexed: 05/24/2023]
Abstract
Temperature is one of the main factors controlling the formation, development, and functional performance of the photosynthetic apparatus in all photoautotrophs (green plants, algae, and cyanobacteria) on Earth. The projected climate change scenarios predict increases in air temperature across Earth's biomes ranging from moderate (3-4 °C) to extreme (6-8 °C) by the year 2100 (IPCC in Climate change 2007: The physical science basis: summery for policymakers, IPCC WG1 Fourth Assessment Report 2007; Climate change 2014: Mitigation of Climate Change, IPCC WG3 Fifth Assessment Report 2014). In some areas, especially of the Northern hemisphere, even more extreme warm seasonal temperatures may occur, which possibly will cause significant negative effects on the development, growth, and yield of important agricultural crops. It is well documented that high temperatures can cause direct damages of the photosynthetic apparatus and photosystem II (PSII) is generally considered to be the primary target of heat-induced inactivation of photosynthesis. However, since photosystem I (PSI) is considered to determine the global amount of enthalpy in living systems (Nelson in Biochim Biophys Acta 1807:856-863, 2011; Photosynth Res 116:145-151, 2013), the effects of elevated temperatures on PSI might be of vital importance for regulating the photosynthetic response of all photoautotrophs in the changing environment. In this review, we summarize the experimental data that demonstrate the critical impact of heat-induced alterations on the structure, composition, and functional performance of PSI and their significant implications on photosynthesis under future climate change scenarios.
Collapse
Affiliation(s)
- Alexander G Ivanov
- Department of Biology, University of Western Ontario, 1151 Richmond Street N., London, ON, N6A 5B7, Canada.
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 21, 1113, Sofia, Bulgaria.
| | - Maya Y Velitchkova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 21, 1113, Sofia, Bulgaria
| | - Suleyman I Allakhverdiev
- Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, 127276, Russia
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow, 142290, Russia
- Department of Plant Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
- Institute of Molecular Biology and Biotechnology, Azerbaijan National Academy of Sciences, Matbuat Avenue 2a, 1073, Baku, Azerbaijan
| | - Norman P A Huner
- Department of Biology, University of Western Ontario, 1151 Richmond Street N., London, ON, N6A 5B7, Canada
| |
Collapse
|
10
|
Paredes M, Quiles MJ. Chilling stress and hydrogen peroxide accumulation in Chrysanthemum morifolium and Spathiphyllum lanceifolium. Involvement of chlororespiration. JOURNAL OF PLANT PHYSIOLOGY 2017; 211:36-41. [PMID: 28142095 DOI: 10.1016/j.jplph.2016.11.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 11/28/2016] [Accepted: 11/29/2016] [Indexed: 05/11/2023]
Abstract
Plants of Chrysanthemum morifolium (sun species) and Spathiphyllum lanceifolium (shade species) were used to study the effects of chilling stems under high illumination. The stress conditions resulted in a greater accumulation of H2O2 in C. morifolium than in S. lanceifolium, and in the down-regulation of photosynthetic linear electron transport in both species. However, only a slight decrease in the maximal quantum yield of PSII was observed under unfavorable conditions in both species, suggesting that mechanisms exist in the chloroplasts that dissipate excess excitation energy and prevent damage to the photosynthetic apparatus. Additionally, changes were observed in the PGR5 polypeptide involved in cyclic electron flow around PSI and in chlororespiratory enzymes (plastidial NDH complex and PTOX). The level of PGR5 increased significantly only in chilled plants of C. morifolium, whereas the levels of the PTOX and NDH-H polypeptide of the plastidial NDH complex and the NDH activity increased significantly only in chilled plants of S. lanceifolium. These findings suggest that the cyclic electron flow involving PGR5 is more active in C. morifolium, while in S. lanceifolium, other mechanisms involving chlororespiratory enzymes are stimulated in response to chilling and high light, resulting in less H2O2 being accumulated in leaves.
Collapse
Affiliation(s)
- Miriam Paredes
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain
| | - María José Quiles
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain.
| |
Collapse
|
11
|
Vanlerberghe GC, Martyn GD, Dahal K. Alternative oxidase: a respiratory electron transport chain pathway essential for maintaining photosynthetic performance during drought stress. PHYSIOLOGIA PLANTARUM 2016; 157:322-37. [PMID: 27080742 DOI: 10.1111/ppl.12451] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 03/11/2016] [Indexed: 05/19/2023]
Abstract
Photosynthesis and respiration are the hubs of energy metabolism in plants. Drought strongly perturbs photosynthesis as a result of both diffusive limitations resulting from stomatal closure, and in some cases biochemical limitations that are associated with a reduced abundance of key photosynthetic components. The effects of drought on respiration, particularly respiration in the light (RL ), are less understood. The plant mitochondrial electron transport chain includes a non-energy conserving terminal oxidase called alternative oxidase (AOX). Several studies have shown that drought increases AOX transcript, protein and maximum capacity. Here we review recent studies comparing wild-type (WT) tobacco to transgenic lines with altered AOX protein amount. Specifically during drought, RL was compromised in AOX knockdown plants and enhanced in AOX overexpression plants, compared with WT. Significantly, these differences in RL were accompanied by dramatic differences in photosynthetic performance. Knockdown of AOX increased the susceptibility of photosynthesis to drought-induced biochemical limitations, while overexpression of AOX delayed the development of such biochemical limitations, compared with WT. Overall, the results indicate that AOX is essential to maintaining RL during drought, and that this non-energy conserving respiration maintains photosynthesis during drought by promoting energy balance in the chloroplast. This review also outlines several areas for future research, including the possibility that enhancement of non-energy conserving respiratory electron sinks may be a useful biotechnological approach to increase plant performance during stress.
Collapse
Affiliation(s)
- Greg C Vanlerberghe
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
- Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| | - Greg D Martyn
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
- Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| | - Keshav Dahal
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
- Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, M1C1A4, Canada
| |
Collapse
|
12
|
Li Q, Yao ZJ, Mi H. Alleviation of Photoinhibition by Co-ordination of Chlororespiration and Cyclic Electron Flow Mediated by NDH under Heat Stressed Condition in Tobacco. FRONTIERS IN PLANT SCIENCE 2016; 7:285. [PMID: 27066014 PMCID: PMC4811903 DOI: 10.3389/fpls.2016.00285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 02/22/2016] [Indexed: 05/06/2023]
Abstract
With increase of temperature, F o gradually rose in both WT and the mutant inactivated in the type 1 NAD(P)H dehydrogenase (NDH), a double mutant disrupted the genes of ndhJ and ndhK (ΔndhJK) or a triple mutant disrupted the genes of ndhC, ndhJ, and ndhK (ΔndhCJK). The temperature threshold of Fo rise was about 3-5°C lower in the mutants than in WT, indicating ΔndhJK and ΔndhCJK were more sensitive to elevated temperature. The F o rise after the threshold was slower and the reached maximal level was lower in the mutants than in WT, implying the chlororespiratory pathway was suppressed when NDH was inactivated. Meanwhile, the maximum quantum efficiency of photosystem II (PS II) (F v /F m) decreased to a similar extent below 50°C in WT and mutants. However, the decline was sharper in WT when temperature rose above 55°C, indicating a down regulation of PS II photochemical activity by the chlororespiratory pathway in response to elevated temperature. On the other hand, in the presence of n-propyl gallate, an inhibitor of plastid terminal oxidase (PTOX), the less evident increase in F o while the more decrease in F v /F m in ΔndhCJK than in WT after incubation at 50°C for 6 h suggest the increased sensitivity to heat stress when both NDH and chlororespiratory pathways are suppressed. Moreover, the net photosynthetic rate and photo-efficiency decreased more significantly in ΔndhJK than in WT under the heat stressed conditions. Compared to the light-oxidation of P700, the difference in the dark-reduction of P700(+) between WT and ndhJK disruptant was much less under the heat stressed conditions, implying significantly enhanced cyclic electron flow in light and the competition for electron from PQ between PTOX and photosystem I in the dark at the elevated temperature. Heat-stimulated expression of both NdhK and PTOX significantly increased in WT, while the expression of PTOX was less in ΔndhJK than in WT. Meanwhile, the amount of active form of Rubisco activase decreased much more in the mutant. The results suggest that chlororespiration and cyclic electron flow mediated by NDH may coordinate to alleviate the over-reduction of stroma, thus to keep operation of CO2 assimilation at certain extent under heat stress condition.
Collapse
|
13
|
Suorsa M. Cyclic electron flow provides acclimatory plasticity for the photosynthetic machinery under various environmental conditions and developmental stages. FRONTIERS IN PLANT SCIENCE 2015; 6:800. [PMID: 26442093 PMCID: PMC4585005 DOI: 10.3389/fpls.2015.00800] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 09/14/2015] [Indexed: 05/03/2023]
Abstract
Photosynthetic electron flow operates in two modes, linear and cyclic. In cyclic electron flow (CEF), electrons are recycled around photosystem I. As a result, a transthylakoid proton gradient (ΔpH) is generated, leading to the production of ATP without concomitant production of NADPH, thus increasing the ATP/NADPH ratio within the chloroplast. At least two routes for CEF exist: a PROTON GRADIENT REGULATION5-PGRL1-and a chloroplast NDH-like complex mediated pathway. This review focuses on recent findings concerning the characteristics of both CEF routes in higher plants, with special emphasis paid on the crucial role of CEF in under challenging environmental conditions and developmental stages.
Collapse
Affiliation(s)
- Marjaana Suorsa
- Molecular Plant Biology, Department of Biochemistry, University of TurkuTurku, Finland
| |
Collapse
|
14
|
Paredes M, Quiles MJ. The Effects of Cold Stress on Photosynthesis in Hibiscus Plants. PLoS One 2015; 10:e0137472. [PMID: 26360248 PMCID: PMC4567064 DOI: 10.1371/journal.pone.0137472] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 08/17/2015] [Indexed: 11/19/2022] Open
Abstract
The present work studies the effects of cold on photosynthesis, as well as the involvement in the chilling stress of chlororespiratory enzymes and ferredoxin-mediated cyclic electron flow, in illuminated plants of Hibiscus rosa-sinensis. Plants were sensitive to cold stress, as indicated by a reduction in the photochemistry efficiency of PSII and in the capacity for electron transport. However, the susceptibility of leaves to cold may be modified by root temperature. When the stem, but not roots, was chilled, the quantum yield of PSII and the relative electron transport rates were much lower than when the whole plant, root and stem, was chilled at 10°C. Additionally, when the whole plant was cooled, both the activity of electron donation by NADPH and ferredoxin to plastoquinone and the amount of PGR5 polypeptide, an essential component of the cyclic electron flow around PSI, increased, suggesting that in these conditions cyclic electron flow helps protect photosystems. However, when the stem, but not the root, was cooled cyclic electron flow did not increase and PSII was damaged as a result of insufficient dissipation of the excess light energy. In contrast, the chlororespiratory enzymes (NDH complex and PTOX) remained similar to control when the whole plant was cooled, but increased when only the stem was cooled, suggesting the involvement of chlororespiration in the response to chilling stress when other pathways, such as cyclic electron flow around PSI, are insufficient to protect PSII.
Collapse
Affiliation(s)
- Miriam Paredes
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Murcia, Spain
| | - María José Quiles
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Murcia, Spain
- * E-mail:
| |
Collapse
|
15
|
Segura MV, Quiles MJ. Involvement of chlororespiration in chilling stress in the tropical species Spathiphyllum wallisii. PLANT, CELL & ENVIRONMENT 2015; 38:525-33. [PMID: 25041194 DOI: 10.1111/pce.12406] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 05/23/2014] [Accepted: 07/07/2014] [Indexed: 05/06/2023]
Abstract
Spathiphyllum wallisii plants were used to study the effect of chilling stress under high illumination on photosynthesis and chlororespiration. Leaves showed different responses that depended on root temperature. When stem, but not root, was chilled, photosystem II (PSII) was strongly photoinhibited. However, when the whole plant was chilled, the maximal quantum yield of PSII decreased only slightly below the normal values and cyclic electron transport was stimulated. Changes were also observed in the chlororespiration enzymes and PGR5. In whole plants chilled under high illumination, the amounts of NADH dehydrogenase (NDH) complex and plastid terminal oxidase (PTOX) remained similar to control and increased when only stem was chilled. In contrast, the amount of PGR5 polypeptide was higher in plants when both root and stem were chilled than in plants in which only stem was chilled. The results indicated that the contribution of chlororespiration to regulating photosynthetic electron flow is not relevant when the whole plant is chilled under high light, and that another pathway, such as cyclic electron flow involving PGR5 polypeptide, may be more important. However, when PSII activity is strongly photoinhibited in plants in which only stem is chilled, chlororespiration, together with other routes of electron input to the electron transfer chain, is probably essential.
Collapse
Affiliation(s)
- María V Segura
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Murcia, E-30100, Spain
| | | |
Collapse
|
16
|
Nawrocki WJ, Tourasse NJ, Taly A, Rappaport F, Wollman FA. The plastid terminal oxidase: its elusive function points to multiple contributions to plastid physiology. ANNUAL REVIEW OF PLANT BIOLOGY 2015; 66:49-74. [PMID: 25580838 DOI: 10.1146/annurev-arplant-043014-114744] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Plastids have retained from their cyanobacterial ancestor a fragment of the respiratory electron chain comprising an NADPH dehydrogenase and a diiron oxidase, which sustain the so-called chlororespiration pathway. Despite its very low turnover rates compared with photosynthetic electron flow, knocking out the plastid terminal oxidase (PTOX) in plants or microalgae leads to severe phenotypes that encompass developmental and growth defects together with increased photosensitivity. On the basis of a phylogenetic and structural analysis of the enzyme, we discuss its physiological contribution to chloroplast metabolism, with an emphasis on its critical function in setting the redox poise of the chloroplast stroma in darkness. The emerging picture of PTOX is that of an enzyme at the crossroads of a variety of metabolic processes, such as, among others, the regulation of cyclic electron transfer and carotenoid biosynthesis, which have in common their dependence on the redox state of the plastoquinone pool, set largely by the activity of PTOX in darkness.
Collapse
Affiliation(s)
- Wojciech J Nawrocki
- Laboratoire de Physiologie Membranaire et Moléculaire du Chloroplaste, UMR 7141, Centre National de la Recherche Scientifique-Université Pierre et Marie Curie
| | | | | | | | | |
Collapse
|
17
|
Renato M, Boronat A, Azcón-Bieto J. Respiratory processes in non-photosynthetic plastids. FRONTIERS IN PLANT SCIENCE 2015; 6:496. [PMID: 26236317 PMCID: PMC4505080 DOI: 10.3389/fpls.2015.00496] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 06/22/2015] [Indexed: 05/22/2023]
Abstract
Chlororespiration is a respiratory process located in chloroplast thylakoids which consists in an electron transport chain from NAD(P)H to oxygen. This respiratory chain involves the NAD(P)H dehydrogenase complex, the plastoquinone pool and the plastid terminal oxidase (PTOX), and it probably acts as a safety valve to prevent the over-reduction of the photosynthetic machinery in stress conditions. The existence of a similar respiratory activity in non-photosynthetic plastids has been less studied. Recently, it has been reported that tomato fruit chromoplasts present an oxygen consumption activity linked to ATP synthesis. Etioplasts and amyloplasts contain several electron carriers and some subunits of the ATP synthase, so they could harbor a similar respiratory process. This review provides an update on the study about respiratory processes in chromoplasts, identifying the major gaps that need to be addressed in future research. It also reviews the proteomic data of etioplasts and amyloplasts, which suggest the presence of a respiratory electron transport chain in these plastids.
Collapse
Affiliation(s)
- Marta Renato
- Departament de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Centre de Recerca en Agrigenòmica, Consorci CSIC-IRTA-UAB-UB, Campus Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Albert Boronat
- Centre de Recerca en Agrigenòmica, Consorci CSIC-IRTA-UAB-UB, Campus Universitat Autònoma de Barcelona, Bellaterra, Spain
- Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Joaquín Azcón-Bieto
- Departament de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- *Correspondence: Joaquín Azcón-Bieto, Departament de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, Barcelona 08028, Spain,
| |
Collapse
|
18
|
Soto A, Hernández L, Quiles MJ. High root temperature affects the tolerance to high light intensity in Spathiphyllum plants. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2014; 227:84-9. [PMID: 25219310 DOI: 10.1016/j.plantsci.2014.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 07/03/2014] [Accepted: 07/06/2014] [Indexed: 05/06/2023]
Abstract
Spathiphyllum wallisii plants were sensitive to temperature stress under high illumination, although the susceptibility of leaves to stress may be modified by root temperature. Leaves showed higher tolerance to high illumination, in both cold and heat conditions, when the roots were cooled, probably because the chloroplast were protected by excess excitation energy dissipation mechanisms such as cyclic electron transport. When the roots were cooled both the activity of electron donation by NADPH and ferredoxin to plastoquinone and the amount of PGR5 polypeptide, an essential component of cyclic electron flow around PSI, increased. However, when the stems were heated or cooled under high illumination, but the roots were heated, the quantum yield of PSII decreased considerably and neither the electron donation activity by NADPH and ferredoxin to plastoquinone nor the amount of PGR5 polypeptide increased. In such conditions, the cyclic electron flow cannot be enhanced by high light and PSII is damaged as a result of insufficient dissipation of excess light energy. Additionally, the damage to PSII induced the increase in both chlororespiratory enzymes, NDH complex and PTOX.
Collapse
Affiliation(s)
- Adriana Soto
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain
| | - Laura Hernández
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain
| | - María José Quiles
- Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain.
| |
Collapse
|
19
|
Martínez-Alberola F, del Campo EM, Lázaro-Gimeno D, Mezquita-Claramonte S, Molins A, Mateu-Andrés I, Pedrola-Monfort J, Casano LM, Barreno E. Balanced gene losses, duplications and intensive rearrangements led to an unusual regularly sized genome in Arbutus unedo chloroplasts. PLoS One 2013; 8:e79685. [PMID: 24260278 PMCID: PMC3832540 DOI: 10.1371/journal.pone.0079685] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 09/24/2013] [Indexed: 11/25/2022] Open
Abstract
Completely sequenced plastomes provide a valuable source of information about the duplication, loss, and transfer events of chloroplast genes and phylogenetic data for resolving relationships among major groups of plants. Moreover, they can also be useful for exploiting chloroplast genetic engineering technology. Ericales account for approximately six per cent of eudicot diversity with 11,545 species from which only three complete plastome sequences are currently available. With the aim of increasing the number of ericalean complete plastome sequences, and to open new perspectives in understanding Mediterranean plant adaptations, a genomic study on the basis of the complete chloroplast genome sequencing of Arbutus unedo and an updated phylogenomic analysis of Asteridae was implemented. The chloroplast genome of A. unedo shows extensive rearrangements but a medium size (150,897 nt) in comparison to most of angiosperms. A number of remarkable distinct features characterize the plastome of A. unedo: five-fold dismissing of the SSC region in relation to most angiosperms; complete loss or pseudogenization of a number of essential genes; duplication of the ndhH-D operon and its location within the two IRs; presence of large tandem repeats located near highly re-arranged regions and pseudogenes. All these features outline the primary evolutionary split between Ericaceae and other ericalean families. The newly sequenced plastome of A. unedo with the available asterid sequences allowed the resolution of some uncertainties in previous phylogenies of Asteridae.
Collapse
Affiliation(s)
- Fernando Martínez-Alberola
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| | - Eva M. del Campo
- Departamento de Ciencias de la Vida, Facultad de Biología, Ciencias Ambientales y Química, Universidad de Alcalá, Madrid, Spain
| | - David Lázaro-Gimeno
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| | - Sergio Mezquita-Claramonte
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| | - Arantxa Molins
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| | - Isabel Mateu-Andrés
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| | - Joan Pedrola-Monfort
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| | - Leonardo M. Casano
- Departamento de Ciencias de la Vida, Facultad de Biología, Ciencias Ambientales y Química, Universidad de Alcalá, Madrid, Spain
| | - Eva Barreno
- ICBIBE, Departamento de Botánica, Facultad de Ciencias Biológicas, Universitat de València, Burjassot, Valencia, Spain
| |
Collapse
|
20
|
Muñoz R, Quiles MJ. Water deficit and heat affect the tolerance to high illumination in hibiscus plants. Int J Mol Sci 2013; 14:5432-44. [PMID: 23470922 PMCID: PMC3634501 DOI: 10.3390/ijms14035432] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 03/01/2013] [Accepted: 03/04/2013] [Indexed: 11/16/2022] Open
Abstract
This work studies the effects of water deficit and heat, as well as the involvement of chlororespiration and the ferredoxin-mediated cyclic pathway, on the tolerance of photosynthesis to high light intensity in Hibiscus rosa-sinensis plants. Drought and heat resulted in the down–regulation of photosynthetic linear electron transport in the leaves, although only a slight decrease in variable fluorescence (Fv)/maximal fluorescence (Fm) was observed, indicating that the chloroplast was protected by mechanisms that dissipate excess excitation energy to prevent damage to the photosynthetic apparatus. The incubation of leaves from unstressed plants under high light intensity resulted in an increase of the activity of electron donation by nicotinamide adenine dinucleotide phosphate (NADPH) and ferredoxin to plastoquinone, but no increase was observed in plants exposed to water deficit, suggesting that cyclic electron transport was stimulated by high light only in control plants. In contrast, the activities of the chlororespiration enzymes (NADH dehydrogenase (NDH) complex and plastid terminal oxidase (PTOX)) increased after incubation under high light intensity in leaves of the water deficit plants, but not in control plants, suggesting that chlororespiration was stimulated in stressed plants. The results indicate that the relative importance of chlororespiration and the cyclic electron pathway in the tolerance of photosynthesis to high illumination differs under stress conditions. When plants were not subjected to stress, the contribution of chlororespiration to photosynthetic electron flow regulation was not relevant, and another pathway, such as the ferredoxin-mediated cyclic pathway, was more important. However, when plants were subjected to water deficit and heat, chlororespiration was probably essential.
Collapse
Affiliation(s)
- Romualdo Muñoz
- Department of Plant Biology, University of Murcia, 30100 Espinardo Murcia, Spain.
| | | |
Collapse
|
21
|
Sabater B, Martín M. Hypothesis: increase of the ratio singlet oxygen plus superoxide radical to hydrogen peroxide changes stress defense response to programmed leaf death. FRONTIERS IN PLANT SCIENCE 2013; 4:479. [PMID: 24324479 PMCID: PMC3839260 DOI: 10.3389/fpls.2013.00479] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/05/2013] [Indexed: 05/07/2023]
Abstract
The level of reactive oxygen species (ROS) increases under different stresses and, by destroying cellular components, may cause cell death. In addition, ROS are part of the complex network of transduction signals that induce defense reactions against stress or, alternatively, trigger programmed cell death, and key questions are the levels of each ROS that, respectively determine defense and death responses of the cell. The answer to those questions is difficult because there are several patterns of cell death that frequently appear mixed and are hardly distinguishable. Moreover, although considerable progresses have been achieved in the determination of the levels of specific ROS, critical questions remain on the ROS level in specific cell compartments. By considering chloroplasts as the main source of ROS in photosynthetic tissues at light, a comparison of the levels in stress and senescence of the chloroplastic activities involved in the generation and scavenging of ROS suggests plausible differences in the levels of specific ROS between stress defense and death. In effect, the three activities of the chlororespiratory chain increase similarly in stress defense response. However, in senescence, superoxide dismutase (SOD), that converts superoxide anion radical ([Formula: see text]) to hydrogen peroxide (H2O2,) decreases, while the thylakoid Ndh complex, that favors the generation of singlet oxygen ((1)O2) and [Formula: see text], and peroxidase (PX), that consumes H2O2, increase. The obvious inference is that, in respect to defense response, the ratio ((1)O2 plus [Formula: see text])/H2O2 is increased in the senescence previous to cell death. We hypothesize that the different ROS ratios, probably through changes in the jasmonic acid/H2O2 ratio, could determine the activation of the defense network or the death network response of the cell.
Collapse
Affiliation(s)
- Bartolomé Sabater
- *Correspondence: Bartolomé Sabater, Departamento de Ciencias de la Vida (Fisiología Vegetal), Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain e-mail:
| | | |
Collapse
|