1
|
Tanimoto H, Umekawa Y, Takahashi H, Goto K, Ito K. Gene expression and metabolite levels converge in the thermogenic spadix of skunk cabbage. PLANT PHYSIOLOGY 2024; 195:1561-1585. [PMID: 38318875 PMCID: PMC11142342 DOI: 10.1093/plphys/kiae059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/11/2024] [Accepted: 01/11/2024] [Indexed: 02/07/2024]
Abstract
The inflorescence (spadix) of skunk cabbage (Symplocarpus renifolius) is strongly thermogenic and can regulate its temperature at around 23 °C even when the ambient temperature drops below freezing. To elucidate the mechanisms underlying developmentally controlled thermogenesis and thermoregulation in skunk cabbage, we conducted a comprehensive transcriptome and metabolome analysis across 3 developmental stages of spadix development. Our RNA-seq analysis revealed distinct groups of expressed genes, with selenium-binding protein 1/methanethiol oxidase (SBP1/MTO) exhibiting the highest levels in thermogenic florets. Notably, the expression of alternative oxidase (AOX) was consistently high from the prethermogenic stage through the thermogenic stage in the florets. Metabolome analysis showed that alterations in nucleotide levels correspond with the developmentally controlled and tissue-specific thermogenesis of skunk cabbage, evident by a substantial increase in AMP levels in thermogenic florets. Our study also reveals that hydrogen sulfide, a product of SBP1/MTO, inhibits cytochrome c oxidase (COX)-mediated mitochondrial respiration, while AOX-mediated respiration remains relatively unaffected. Specifically, at lower temperatures, the inhibitory effect of hydrogen sulfide on COX-mediated respiration increases, promoting a shift toward the dominance of AOX-mediated respiration. Finally, despite the differential regulation of genes and metabolites throughout spadix development, we observed a convergence of gene expression and metabolite accumulation patterns during thermogenesis. This synchrony may play a key role in developmentally regulated thermogenesis. Moreover, such convergence during the thermogenic stage in the spadix may provide a solid molecular basis for thermoregulation in skunk cabbage.
Collapse
Affiliation(s)
- Haruka Tanimoto
- United Graduate School of Agricultural Science, Iwate University, Morioka, Iwate 020-8550, Japan
| | - Yui Umekawa
- Department of Planning and General Affairs, Akita Research Institute of Food and Brewing, Araya-machi, Akita 010-1623, Japan
| | - Hideyuki Takahashi
- Department of Agriculture, School of Agriculture, Tokai University, Kumamoto 862-8652, Japan
| | - Kota Goto
- Faculty of Agriculture, Iwate University, Morioka, Iwate 020-8550, Japan
| | - Kikukatsu Ito
- United Graduate School of Agricultural Science, Iwate University, Morioka, Iwate 020-8550, Japan
- Faculty of Agriculture, Iwate University, Morioka, Iwate 020-8550, Japan
| |
Collapse
|
2
|
Xu J, Zhao X, Zhong Y, Qu T, Sun B, Zhang H, Hou C, Zhang Z, Tang X, Wang Y. Acclimation of intertidal macroalgae Ulva prolifera to UVB radiation: the important role of alternative oxidase. BMC PLANT BIOLOGY 2024; 24:143. [PMID: 38413873 PMCID: PMC10900725 DOI: 10.1186/s12870-024-04762-w] [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: 04/11/2023] [Accepted: 01/23/2024] [Indexed: 02/29/2024]
Abstract
BACKGROUND Solar radiation is primarily composed of ultraviolet radiation (UVR, 200 - 400 nm) and photosynthetically active radiation (PAR, 400 - 700 nm). Ultraviolet-B (UVB) radiation accounts for only a small proportion of sunlight, and it is the primary cause of plant photodamage. The use of chlorofluorocarbons (CFCs) as refrigerants caused serious ozone depletion in the 1980s, and this had led to an increase in UVB. Although CFC emissions have significantly decreased in recent years, UVB radiation still remains at a high intensity. UVB radiation increase is an important factor that influences plant physiological processes. Ulva prolifera, a type of macroalga found in the intertidal zone, is intermittently exposed to UVB. Alternative oxidase (AOX) plays an important role in plants under stresses. This research examines the changes in AOX activity and the relationships among AOX, photosynthesis, and reactive oxygen species (ROS) homeostasis in U. prolifera under changes in UVB and photosynthetically active radiation (PAR). RESULTS UVB was the main component of solar radiation impacting the typical intertidal green macroalgae U. prolifera. AOX was found to be important during the process of photosynthesis optimization of U. prolifera due to a synergistic effect with non-photochemical quenching (NPQ) under UVB radiation. AOX and glycolate oxidase (GO) worked together to achieve NADPH homeostasis to achieve photosynthesis optimization under changes in PAR + UVB. The synergism of AOX with superoxide dismutase (SOD) and catalase (CAT) was important during the process of ROS homeostasis under PAR + UVB. CONCLUSIONS AOX plays an important role in the process of photosynthesis optimization and ROS homeostasis in U. prolifera under UVB radiation. This study provides further insights into the response of intertidal macroalgae to solar light changes.
Collapse
Grants
- No. LSKJ202203605 Laoshan Laboratory
- Nos. 41906120, 42176204, 41976132, and 41706121 National Natural Science Foundation of China
- Nos. 41906120, 42176204, 41976132, and 41706121 National Natural Science Foundation of China
- Nos. 41906120, 42176204, 41976132, and 41706121 National Natural Science Foundation of China
- Nos. 41906120, 42176204, 41976132, and 41706121 National Natural Science Foundation of China
- Nos. U1806213 and U1606404 NSFC-Shandong Joint Fund
- Nos. U1806213 and U1606404 NSFC-Shandong Joint Fund
Collapse
Affiliation(s)
- Jinhui Xu
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Xinyu Zhao
- Laoshan Laboratory, 1 Wenhai Road, Qingdao, 266237, China.
| | - Yi Zhong
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Tongfei Qu
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Baixue Sun
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Huanxin Zhang
- College of Geography and Environment, Shandong Normal University, 1 Daxue Road, Jinan, 250000, China
| | - Chengzong Hou
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Zhipeng Zhang
- Tianjin Research Institute for Water Transport Engineering, Ministry of Transport, Tianjin, 300456, China
| | - Xuexi Tang
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, 1 Wenhai Road, Qingdao, 266237, China
| | - Ying Wang
- College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.
- Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, 1 Wenhai Road, Qingdao, 266237, China.
| |
Collapse
|
3
|
Garmash EV. Suppression of mitochondrial alternative oxidase can result in upregulation of the ROS scavenging network: some possible mechanisms underlying the compensation effect. PLANT BIOLOGY (STUTTGART, GERMANY) 2023; 25:43-53. [PMID: 36245276 DOI: 10.1111/plb.13477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Mitochondrial alternative oxidase is an important protein involved in maintaining cellular metabolic and energy balance, especially under stress conditions. AOX genes knockout is aimed at revealing the functions of AOX genes. Under unfavourable conditions, AOX-suppressed plants (mainly based on Arabidopsis AOX1a-knockout lines) usually experience strong oxidative stress. However, a compensation effect, which consists of the absence of AOX1a leading to an increase in defence response mechanisms, concomitant with a decrease in ROS content, has also been demonstrated. This review briefly describes the possible mechanisms underlying the compensation effect upon the suppression of AOX1a. Information about mitochondrial retrograde regulation of AOX is given. The importance of ROS and mitochondrial membrane potential in triggering the signal transmission from mitochondria in the absence of AOX or disturbance of mitochondrial electron transport chain functions is indicated. The few available data on the response of the cell to the absence of AOX at the level of changes in the hormonal balance and the reactions of chloroplasts are presented. The decrease in the relative amount of reduced ascorbate at stable ROS levels as a result of compensation in AOX1a-suppressed plants is proposed as a sign of stress development. Obtaining direct evidence on the mechanisms and signalling pathways involved in AOX modulation in the genome should facilitate a deeper understanding of the role of AOX in the integration of cellular signalling pathways.
Collapse
Affiliation(s)
- E V Garmash
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| |
Collapse
|
4
|
Romero-Aguilar L, Vázquez-Meza H, Guerra-Sánchez G, Luqueño-Bocardo OI, Pardo JP. The Mitochondrial Alternative Oxidase in Ustilago maydis Is Not Involved in Response to Oxidative Stress Induced by Paraquat. J Fungi (Basel) 2022; 8:1221. [PMID: 36422042 PMCID: PMC9693204 DOI: 10.3390/jof8111221] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/10/2022] [Accepted: 11/17/2022] [Indexed: 07/29/2023] Open
Abstract
It has been shown that the alternative oxidase in mitochondria of fungi and plants has important functions in the response against stress conditions, although their role in some organisms is still unknown. This is the case of Ustilago maydis. There is no evidence of the participation of the U. maydis Aox1 in stressful conditions such as desiccation, high or low temperature, and low pH, among others. Therefore, in this work, we studied the role of the U. maydis Aox1 in cells exposed to oxidative stress induced by methyl viologen (paraquat). To gain insights into the role of this enzyme, we took advantage of four strains: the FB2 wild-type, a strain without the alternative oxidase (FB2aox1Δ), other with the Aox1 fused to the Gfp under the control of the original promoter (FB2aox1-Gfp), and one expressing constitutively de Aox1-Gfp (FB2Potef:aox1-Gfp). Cells were incubated for various times in the presence of 1 mM paraquat and growth, replicative capacities, mitochondrial respiratory activity, Aox1 capacity, and the activities of several antioxidant enzymes (catalase, glutathione peroxidase, glutathione reductase, and superoxide dismutase) were assayed. The results show that (1) the response of U. maydis against oxidative stress was the same in the presence or absence of the Aox1; (2) the activities of the antioxidant enzymes remained constant despite the oxidative stress; and (3) there was a decrease in the GSH/GSSG ratio in U. maydis cells incubated with paraquat.
Collapse
Affiliation(s)
- Lucero Romero-Aguilar
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico
| | - Héctor Vázquez-Meza
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico
| | - Guadalupe Guerra-Sánchez
- Instituto Politécnico Nacional, Escuela Nacional de Ciencias Biológicas, Departamento de Microbiología, Plan de Carpio y Plan de Ayala S/N Santo Tomás, Miguel Hidalgo, Ciudad de México C.P. 11340, Mexico
| | - Oscar Ivan Luqueño-Bocardo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico
| | - Juan Pablo Pardo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico
| |
Collapse
|
5
|
Sweetman C, Waterman CD, Wong DC, Day DA, Jenkins CL, Soole KL. Altering the balance between AOX1A and NDB2 expression affects a common set of transcripts in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2022; 13:876843. [PMID: 36466234 PMCID: PMC9716356 DOI: 10.3389/fpls.2022.876843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 10/24/2022] [Indexed: 06/17/2023]
Abstract
Stress-responsive components of the mitochondrial alternative electron transport pathway have the capacity to improve tolerance of plants to abiotic stress, particularly the alternative oxidase AOX1A but also external NAD(P)H dehydrogenases such as NDB2, in Arabidopsis. NDB2 and AOX1A can cooperate to entirely circumvent the classical electron transport chain in Arabidopsis mitochondria. Overexpression of AOX1A or NDB2 alone can have slightly negative impacts on plant growth under optimal conditions, while simultaneous overexpression of NDB2 and AOX1A can reverse these phenotypic effects. We have taken a global transcriptomic approach to better understand the molecular shifts that occur due to overexpression of AOX1A alone and with concomitant overexpression of NDB2. Of the transcripts that were significantly up- or down- regulated in the AOX1A overexpression line compared to wild type (410 and 408, respectively), the majority (372 and 337, respectively) reverted to wild type levels in the dual overexpression line. Several mechanisms for the AOX1A overexpression phenotype are proposed based on the functional classification of these 709 genes, which can be used to guide future experiments. Only 28 genes were uniquely up- or down-regulated when NDB2 was overexpressed in the AOX1A overexpression line. On the other hand, many unique genes were deregulated in the NDB2 knockout line. Furthermore, several changes in transcript abundance seen in the NDB2 knockout line were consistent with changes in the AOX1A overexpression line. The results suggest that an imbalance in AOX1A:NDB2 protein levels caused by under- or over-expression of either component, triggers a common set of transcriptional responses that may be important in mitochondrial redox regulation. The most significant changes were transcripts associated with photosynthesis, secondary metabolism and oxidative stress responses.
Collapse
Affiliation(s)
- Crystal Sweetman
- College of Science & Engineering, Flinders University, Bedford Park, SA, Australia
| | | | - Darren C.J. Wong
- College of Science, Australian National University, Canberra, ACT, Australia
| | - David A. Day
- College of Science & Engineering, Flinders University, Bedford Park, SA, Australia
| | - Colin L.D. Jenkins
- College of Science & Engineering, Flinders University, Bedford Park, SA, Australia
| | - Kathleen L. Soole
- College of Science & Engineering, Flinders University, Bedford Park, SA, Australia
| |
Collapse
|
6
|
Korayem A, Safwat El- H, Shater Abd M, Abd El-Mon A, Mohamed Mo M, El-Ashry S. Physiological and Biochemical Changes in the Wheat Plant (Triticum aestivum L.) Infected with Nematodes. ASIAN JOURNAL OF PLANT SCIENCES 2022; 21:613-628. [DOI: 10.3923/ajps.2022.613.628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
|
7
|
El-Khoury R, Rak M, Bénit P, Jacobs HT, Rustin P. Cyanide resistant respiration and the alternative oxidase pathway: A journey from plants to mammals. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148567. [PMID: 35500614 DOI: 10.1016/j.bbabio.2022.148567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/06/2022] [Accepted: 04/18/2022] [Indexed: 12/19/2022]
Abstract
In a large number of organisms covering all phyla, the mitochondrial respiratory chain harbors, in addition to the conventional elements, auxiliary proteins that confer adaptive metabolic plasticity. The alternative oxidase (AOX) represents one of the most studied auxiliary proteins, initially identified in plants. In contrast to the standard respiratory chain, the AOX mediates a thermogenic cyanide-resistant respiration; a phenomenon that has been of great interest for over 2 centuries in that energy is not conserved when electrons flow through it. Here we summarize centuries of studies starting from the early observations of thermogenicity in plants and the identification of cyanide resistant respiration, to the fascinating discovery of the AOX and its current applications in animals under normal and pathological conditions.
Collapse
Affiliation(s)
- Riyad El-Khoury
- American University of Beirut Medical Center, Pathology and Laboratory Medicine Department, Cairo Street, Hamra, Beirut, Lebanon
| | - Malgorzata Rak
- Université Paris Cité, Inserm, Maladies neurodéveloppementales et neurovasculaires, F-75019 Paris, France
| | - Paule Bénit
- Université Paris Cité, Inserm, Maladies neurodéveloppementales et neurovasculaires, F-75019 Paris, France
| | - Howard T Jacobs
- Faculty of Medicine and Health Technology, FI-33014, Tampere University, Finland; Institute of Biotechnology, University of Helsinki, Helsinki, Finland.
| | - Pierre Rustin
- Université Paris Cité, Inserm, Maladies neurodéveloppementales et neurovasculaires, F-75019 Paris, France.
| |
Collapse
|
8
|
Tikoria R, Kaur A, Ohri P. Potential of vermicompost extract in enhancing the biomass and bioactive components along with mitigation of Meloidogyne incognita-induced stress in tomato. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:56023-56036. [PMID: 35332451 DOI: 10.1007/s11356-022-19757-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 03/12/2022] [Indexed: 06/14/2023]
Abstract
Increasing inorganic fertilizer and pesticide use has been linked to increased health risks for humans and cattle, as well as substantial water and soil contamination. In recent years, vermicomposting has shown to be a viable alternative to chemical pesticides. Vermicompost and vermicompost products such as extract and leachate assist plants in a number of ways. According to recent studies, vermicompost extract (VCE), when used as a supplement, is thought to work as a growth and stress tolerance booster for plants. These liquid supplements also help to suppress a range of pests, such as root knot nematodes. In the present study, neem- and cattle dung-based vermicompost extracts of different concentrations (0, 20, 40, 60, 80 and 100%) were prepared and used for their application against nematode infection in tomato seedlings under laboratory conditions. Apart from its antagonistic action against Meloidogyne incognita, the influence of VCE on plant growth was investigated by analyzing its morphological characteristics in tomato seedlings infected and uninfected with M. incognita. Seeds were pre-soaked in VCE for the seed priming process before being allowed for germination. After 10 days of nematode inoculation, biochemical parameters like protein content, activity of antioxidative enzymes, non-enzymatic antioxidants, stress indices, photosynthetic pigments, proline content and secondary metabolites were also analyzed. The results revealed that neem-based VCE was fatal to second-stage juveniles, with an 82% mortality rate following exposure to the highest dose. When eggs were exposed to 100% VCE, 33.8% of hatching was suppressed, indicating that VCE had an antagonistic effect on nematode egg hatching. Further, all the morphological and biochemical parameters were significantly enhanced in VCE-treated tomato seedlings as compared to untreated seedlings. Stress indices were also found to be significantly lowered by the VCE treatments in the infected plants. The effect of VCE on seedling growth and physiology was shown to be concentration dependent. As a result, the current findings show that VCE has the potential to be used as a plant growth accelerator as well as an environmentally friendly biocontrol agent against nematode pathogenesis in tomato plants.
Collapse
Affiliation(s)
- Raman Tikoria
- Department of Zoology, Guru Nanak Dev University, Amritsar, Punjab-143005, India
| | - Arvinder Kaur
- Department of Zoology, Guru Nanak Dev University, Amritsar, Punjab-143005, India
| | - Puja Ohri
- Department of Zoology, Guru Nanak Dev University, Amritsar, Punjab-143005, India.
| |
Collapse
|
9
|
Zafari S, Vanlerberghe GC, Igamberdiev AU. The Role of Alternative Oxidase in the Interplay between Nitric Oxide, Reactive Oxygen Species, and Ethylene in Tobacco ( Nicotiana tabacum L.) Plants Incubated under Normoxic and Hypoxic Conditions. Int J Mol Sci 2022; 23:7153. [PMID: 35806157 PMCID: PMC9266549 DOI: 10.3390/ijms23137153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 06/24/2022] [Indexed: 02/05/2023] Open
Abstract
The transgenic tobacco (Nicotiana tabacum L.) plants with the modified levels of alternative oxidase (AOX) were used to evaluate the physiological roles of AOX in regulating nitro-oxidative stress and metabolic changes after exposing plants to hypoxia for 6 h. Under normoxia, AOX expression resulted in the decrease of nitric oxide (NO) levels and of the rate of protein S-nitrosylation, while under hypoxia, AOX overexpressors exhibited higher NO and S-nitrosylation levels than knockdowns. AOX expression was essential in avoiding hypoxia-induced superoxide and H2O2 levels, and this was achieved via higher activities of catalase and glutathione reductase and the reduced expression of respiratory burst oxidase homolog (Rboh) in overexpressors as compared to knockdowns. The AOX overexpressing lines accumulated less pyruvate and exhibited the increased transcript and activity levels of pyruvate decarboxylase and alcohol dehydrogenase under hypoxia. This suggests that AOX contributes to the energy state of hypoxic tissues by stimulating the increase of pyruvate flow into fermentation pathways. Ethylene biosynthesis genes encoding 1-aminocyclopropane-1-carboxylic acid (ACC) synthase, ACC oxidase, and ethylene-responsive factors (ERFs) were induced during hypoxia and correlated with AOX and NO levels. We conclude that AOX controls the interaction of NO, reactive oxygen species, and ethylene, triggering a coordinated downstream defensive response against hypoxia.
Collapse
Affiliation(s)
- Somaieh Zafari
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
| | - Greg C. Vanlerberghe
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada;
- Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON M1C 1A4, Canada
| | - Abir U. Igamberdiev
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL A1C 5S7, Canada
| |
Collapse
|
10
|
Exogenous Melatonin Protects Lime Plants from Drought Stress-Induced Damage by Maintaining Cell Membrane Structure, Detoxifying ROS and Regulating Antioxidant Systems. HORTICULTURAE 2022. [DOI: 10.3390/horticulturae8030257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Lime is an important commercial product in tropical and subtropical regions, where drought stress is becoming one of the most severe environmental challenges in the agricultural sector. Melatonin is an antioxidant molecule that helps plants regulate their development and respond to a variety of stresses. In this research, the effects of exogenous melatonin treatments were evaluated at different concentrations (0, 50, 100, and 150 μM) on biochemical aspects and gene expression in two species of lime plants (“Mexican lime” and “Persian lime”) under normal (100% field capacity (FC)) and drought stress conditions (75% and 40% FC). The experiments were factorial and based on a completely randomized design (CRD) with four replicates. Drought stress caused electrolyte leakage (EL) as well as accumulations of hydrogen peroxide (H2O2) and malondialdehyde (MDA), indicating the occurrence of damage to cellular membranes. In contrast, the melatonin pretreatment at various concentrations reduced the levels of EL, H2O2 and MDA while mitigating the negative effects of drought stress on the two lime species. The application of melatonin (100-μM) significantly increased the level of proline content and activity of antioxidant enzymes in plants under drought stress compared to control plants. According to real-time PCR analysis, drought stress and melatonin treatment enhanced the expression of genes involved in ROS scavenging, proline biosynthesis, and cell redox regulation in both species, as compared to their respective controls. According to these findings, melatonin is able to detoxify ROS and regulate antioxidant systems, thereby protecting lime plants from drought stress-induced damages.
Collapse
|
11
|
Campos MD, Campos C, Nogales A, Cardoso H. Carrot AOX2a Transcript Profile Responds to Growth and Chilling Exposure. PLANTS (BASEL, SWITZERLAND) 2021; 10:plants10112369. [PMID: 34834732 PMCID: PMC8625938 DOI: 10.3390/plants10112369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 05/28/2023]
Abstract
Alternative oxidase (AOX) is a key enzyme of the alternative respiration, known to be involved in plant development and in response to various stresses. To verify the role of DcAOX1 and DcAOX2a genes in carrot tap root growth and in response to cold stress, their expression was analyzed in two experiments: during root growth for 13 weeks and in response to a cold challenge trial of 7 days, in both cases using different carrot cultivars. Carrot root growth is initially characterized by an increase in length, followed by a strong increase in weight. DcAOX2a presented the highest expression levels during the initial stages of root growth for all cultivars, but DcAOX1 showed no particular trend in expression. Cold stress had a negative impact on root growth, and generally up-regulated DcAOX2a with no consistent effect on DcAOX1. The identification of cis-acting regulatory elements (CAREs) located at the promoters of both genes showed putative sequences involved in cold stress responsiveness, as well as growth. However, DcAOX2a promoter presented more CAREs related to hormonal pathways, including abscisic acid and gibberellins synthesis, than DcAOX1. These results point to a dual role of DcAOX2a on carrot tap root secondary growth and cold stress response.
Collapse
Affiliation(s)
- Maria Doroteia Campos
- MED—Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal; (C.C.); (A.N.)
| | - Catarina Campos
- MED—Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal; (C.C.); (A.N.)
| | - Amaia Nogales
- MED—Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal; (C.C.); (A.N.)
- LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Hélia Cardoso
- MED—Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal; (C.C.); (A.N.)
| |
Collapse
|
12
|
Song C, Zhao Y, Li A, Qi S, Lin Q, Duan Y. Postharvest nitric oxide treatment induced the alternative oxidase pathway to enhance antioxidant capacity and chilling tolerance in peach fruit. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 167:113-122. [PMID: 34352514 DOI: 10.1016/j.plaphy.2021.07.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 07/14/2021] [Accepted: 07/28/2021] [Indexed: 05/18/2023]
Abstract
Nitric oxide (NO) is an important regulator of plant response to cold stress. In this study, NO treatment delayed the development of chilling injury (CI), inhibited the increase in H2O2 content, O2- production rate and decrease in firmness of postharvest peach fruit. Meanwhile, through RNA-seq analysis, NO treatment up-regulated gene expression of PpG-6-PDH, Pp6-PGDH and PpAOX while it down-regulated the expression of PpGPI and PpHK, suggesting that the pentose phosphate respiratory pathway and cyanide-resistant respiratory pathway were promoted and the glycolysis pathway was inhibited. Furthermore, the PpAOX expression was consistent with the trend of PpPOD1/2 expression and H2O2 content, indicating that AOX may play a role in reducing oxidative damage of peach fruit by scavenging H2O2. Thus, it was concluded that NO treatment could induce the cyanide-resistant respiration pathway to enhance antioxidant ability and chilling tolerance in post-harvest peach fruit.
Collapse
Affiliation(s)
- Congcong Song
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Yaoyao Zhao
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Ang Li
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Shuning Qi
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
| | - Qiong Lin
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.
| | - Yuquan Duan
- Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs/ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China.
| |
Collapse
|
13
|
Phua SY, De Smet B, Remacle C, Chan KX, Van Breusegem F. Reactive oxygen species and organellar signaling. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5807-5824. [PMID: 34009340 DOI: 10.1093/jxb/erab218] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 05/14/2021] [Indexed: 05/07/2023]
Abstract
The evolution of photosynthesis and its associated metabolic pathways has been crucial to the successful establishment of plants, but has also challenged plant cells in the form of production of reactive oxygen species (ROS). Intriguingly, multiple forms of ROS are generated in virtually every plant cell compartment through diverse pathways. As a result, a sophisticated network of ROS detoxification and signaling that is simultaneously tailored to individual organelles and safeguards the entire cell is necessary. Here we take an organelle-centric view on the principal sources and sinks of ROS across the plant cell and provide insights into the ROS-induced organelle to nucleus retrograde signaling pathways needed for operational readjustments during environmental stresses.
Collapse
Affiliation(s)
- Su Yin Phua
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| | - Barbara De Smet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| | - Claire Remacle
- Genetics and Physiology of Microalgae, InBios/Phytosystems, Université de Liège, Liège,Belgium
| | - Kai Xun Chan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| | - Frank Van Breusegem
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent,Belgium
- Center for Plant Systems Biology, VIB, Ghent,Belgium
| |
Collapse
|
14
|
Campos MD, Félix MDR, Patanita M, Materatski P, Varanda C. High throughput sequencing unravels tomato-pathogen interactions towards a sustainable plant breeding. HORTICULTURE RESEARCH 2021; 8:171. [PMID: 34333540 PMCID: PMC8325677 DOI: 10.1038/s41438-021-00607-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 06/08/2021] [Accepted: 06/15/2021] [Indexed: 05/24/2023]
Abstract
Tomato (Solanum lycopersicum) is one of the most economically important vegetables throughout the world. It is one of the best studied cultivated dicotyledonous plants, often used as a model system for plant research into classical genetics, cytogenetics, molecular genetics, and molecular biology. Tomato plants are affected by different pathogens such as viruses, viroids, fungi, oomycetes, bacteria, and nematodes, that reduce yield and affect product quality. The study of tomato as a plant-pathogen system helps to accelerate the discovery and understanding of the molecular mechanisms underlying disease resistance and offers the opportunity of improving the yield and quality of their edible products. The use of functional genomics has contributed to this purpose through both traditional and recently developed techniques, that allow the identification of plant key functional genes in susceptible and resistant responses, and the understanding of the molecular basis of compatible interactions during pathogen attack. Next-generation sequencing technologies (NGS), which produce massive quantities of sequencing data, have greatly accelerated research in biological sciences and offer great opportunities to better understand the molecular networks of plant-pathogen interactions. In this review, we summarize important research that used high-throughput RNA-seq technology to obtain transcriptome changes in tomato plants in response to a wide range of pathogens such as viruses, fungi, bacteria, oomycetes, and nematodes. These findings will facilitate genetic engineering efforts to incorporate new sources of resistance in tomato for protection against pathogens and are of major importance for sustainable plant-disease management, namely the ones relying on the plant's innate immune mechanisms in view of plant breeding.
Collapse
Affiliation(s)
- Maria Doroteia Campos
- MED - Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554, Évora, Portugal.
| | - Maria do Rosário Félix
- MED - Mediterranean Institute for Agriculture, Environment and Development & Departamento de Fitotecnia, Escola de Ciências e Tecnologia, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554, Évora, Portugal
| | - Mariana Patanita
- MED - Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554, Évora, Portugal
| | - Patrick Materatski
- MED - Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554, Évora, Portugal
| | - Carla Varanda
- MED - Mediterranean Institute for Agriculture, Environment and Development, Instituto de Investigação e Formação Avançada, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554, Évora, Portugal
| |
Collapse
|
15
|
Wang D, Wang C, Li C, Song H, Qin J, Chang H, Fu W, Wang Y, Wang F, Li B, Hao Y, Xu M, Fu A. Functional Relationship of Arabidopsis AOXs and PTOX Revealed via Transgenic Analysis. FRONTIERS IN PLANT SCIENCE 2021; 12:692847. [PMID: 34367216 PMCID: PMC8336870 DOI: 10.3389/fpls.2021.692847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/07/2021] [Indexed: 06/01/2023]
Abstract
Alternative oxidase (AOX) and plastid terminal oxidase (PTOX) are terminal oxidases of electron transfer in mitochondria and chloroplasts, respectively. Here, taking advantage of the variegation phenotype of the Arabidopsis PTOX deficient mutant (im), we examined the functional relationship between PTOX and its five distantly related homologs (AOX1a, 1b, 1c, 1d, and AOX2). When engineered into chloroplasts, AOX1b, 1c, 1d, and AOX2 rescued the im defect, while AOX1a partially suppressed the mutant phenotype, indicating that AOXs could function as PQH2 oxidases. When the full length AOXs were overexpressed in im, only AOX1b and AOX2 rescued its variegation phenotype. In vivo fluorescence analysis of GFP-tagged AOXs and subcellular fractionation assays showed that AOX1b and AOX2 could partially enter chloroplasts while AOX1c and AOX1d were exclusively present in mitochondria. Surprisingly, the subcellular fractionation, but not the fluorescence analysis of GFP-tagged AOX1a, revealed that a small portion of AOX1a could sort into chloroplasts. We further fused and expressed the targeting peptides of AOXs with the mature form of PTOX in im individually; and found that targeting peptides of AOX1a, AOX1b, and AOX2, but not that of AOX1c or AOX1d, could direct PTOX into chloroplasts. It demonstrated that chloroplast-localized AOXs, but not mitochondria-localized AOXs, can functionally compensate for the PTOX deficiency in chloroplasts, providing a direct evidence for the functional relevance of AOX and PTOX, shedding light on the interaction between mitochondria and chloroplasts and the complex mechanisms of protein dual targeting in plant cells.
Collapse
Affiliation(s)
- Danfeng Wang
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Chunyu Wang
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Cai Li
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Haifeng Song
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Jing Qin
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Han Chang
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Weihan Fu
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Yuhua Wang
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Fei Wang
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Beibei Li
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Yaqi Hao
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Min Xu
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| | - Aigen Fu
- Chinese Education Ministry’s Key Laboratory of Western Resources and Modern Biotechnology, Key Laboratory of Biotechnology Shaanxi Province, College of Life Sciences, Northwest University, Xi’an, China
| |
Collapse
|
16
|
Alber NA, Vanlerberghe GC. The flexibility of metabolic interactions between chloroplasts and mitochondria in Nicotiana tabacum leaf. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:1625-1646. [PMID: 33811402 DOI: 10.1111/tpj.15259] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 05/02/2023]
Abstract
To examine the effect of mitochondrial function on photosynthesis, wild-type and transgenic Nicotiana tabacum with varying amounts of alternative oxidase (AOX) were treated with different respiratory inhibitors. Initially, each inhibitor increased the reduction state of the chloroplast electron transport chain, most severely in AOX knockdowns and least severely in AOX overexpressors. This indicated that the mitochondrion was a necessary sink for photo-generated reductant, contributing to the 'P700 oxidation capacity' of photosystem I. Initially, the Complex III inhibitor myxothiazol and the mitochondrial ATP synthase inhibitor oligomycin caused an increase in photosystem II regulated non-photochemical quenching not evident with the Complex III inhibitor antimycin A (AA). This indicated that the increased quenching depended upon AA-sensitive cyclic electron transport (CET). Following 12 h with oligomycin, the reduction state of the chloroplast electron transport chain recovered in all plant lines. Recovery was associated with large increases in the protein amount of chloroplast ATP synthase and mitochondrial uncoupling protein. This increased the capacity for photophosphorylation in the absence of oxidative phosphorylation and enabled the mitochondrion to act again as a sink for photo-generated reductant. Comparing the AA and myxothiazol treatments at 12 h showed that CET optimized photosystem I quantum yield, depending upon the P700 oxidation capacity. When this capacity was too high, CET drew electrons away from other sinks, moderating the P700+ amount. When P700 oxidation capacity was too low, CET acted as an electron overflow, moderating the amount of reduced P700. This study reveals flexible chloroplast-mitochondrion interactions able to overcome lesions in energy metabolism.
Collapse
Affiliation(s)
- Nicole A Alber
- Department of Biological Sciences, Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON, M1C1A4, Canada
| | - Greg C Vanlerberghe
- Department of Biological Sciences, Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON, M1C1A4, Canada
| |
Collapse
|
17
|
Garmash EV, Belykh ES, Velegzhaninov IO. The gene expression profiles of mitochondrial respiratory components in Arabidopsis plants with differing amounts of ALTERNATIVE OXIDASE1a under high intensity light. PLANT SIGNALING & BEHAVIOR 2021; 16:1864962. [PMID: 33369529 PMCID: PMC7889022 DOI: 10.1080/15592324.2020.1864962] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We compared the expression of mitochondrial alternative oxidase (AOX) and other non-phosphorylating respiratory components (NPhPs) in wild type and AOX1a transgenic Arabidopsis thaliana following short-term transfer of plants to higher irradiance conditions to gain more insight into the mechanisms of AOX functioning under light. The AOX1a overexpressing line (XX-2) showed the highest amount of AOX1a transcripts and AOX1A synthesis during the entire experiment, and many NPhPs genes were down-regulated after 6-8 h under the higher light conditions. Antisense AS-12 plants displayed a compensatory effect, typically after 8 h of exposure to higher irradiance, by up-regulating their expression of the majority of genes encoding AOX and other respiratory components. In addition, AS-12 plants displayed 'overcompensation effects' prior to their transfer to high light conditions, i.e., they showed a higher expression level of certain genes. As a result, the ROS content in AS-12, as in XX-2, was consistently lower than in the wild type. All NPhPs genes share, in common with AOX1a, light- and stress-related cis-acting regulatory elements (CAREs) in their promoters. However, the expression of respiratory genes does not always depend on the level of AOX1a expression. This suggests the presence of multiple combinations of signaling pathways in gene induction. Based on our results, we outline possible directions for future research.
Collapse
Affiliation(s)
- Elena V. Garmash
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
- CONTACT Elena V. Garmash Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| | - Elena S. Belykh
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| | - Ilya O. Velegzhaninov
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| |
Collapse
|
18
|
Ding C, Chen C, Su N, Lyu W, Yang J, Hu Z, Zhang M. Identification and characterization of a natural SNP variant in ALTERNATIVE OXIDASE gene associated with cold stress tolerance in watermelon. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 304:110735. [PMID: 33568287 DOI: 10.1016/j.plantsci.2020.110735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/23/2020] [Accepted: 10/24/2020] [Indexed: 06/12/2023]
Abstract
Alternative oxidase (AOX) is a mitochondrial enzyme encoded by a small nuclear gene family, which contains the two subfamilies, AOX1 and AOX2. In the present study on watermelon (Citrullus lanatus), only one ClAOX gene, belonging to AOX2 subfamily but having a similar gene structure to AtAOX1a, was found in the watermelon genome. The expression analysis suggested that ClAOX had the constitutive expression feature of AOX2 subfamily, but was cold inducible, which is normally considered an AOX1 subfamily feature. Moreover, one single nucleotide polymorphism (SNP) in ClAOX sequence, which led to the change from Lys (N) to Asn (K) in the 96th amino acids, was found among watermelon subspecies. Ectopic expression of two ClAOX alleles in the Arabidopsis aox1a knock-out mutant indicated that ClAOXK-expressing plants had stronger cold tolerance than aox1a mutant and ClAOXN-expressing plants. Our findings suggested watermelon genome contained a single ClAOX that possessed the expression features of both AOX1 and AOX2 subfamilies. A naturally existing SNP in ClAOX differentiated the cold tolerance of transgenic Arabidopsis plants, impling a possibility this gene might be a functional marker for stress-tolerance breeding.
Collapse
Affiliation(s)
- Changqing Ding
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China
| | - Cuiting Chen
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China
| | - Nan Su
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China
| | - Wenhui Lyu
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China
| | - Jinghua Yang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, PR China
| | - Zhongyuan Hu
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, PR China.
| | - Mingfang Zhang
- Laboratory of Germplasm Innovation and Molecular Breeding, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, PR China; Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agriculture, Hangzhou 310058, PR China
| |
Collapse
|
19
|
Popov VN, Syromyatnikov MY, Fernie AR, Chakraborty S, Gupta KJ, Igamberdiev AU. The uncoupling of respiration in plant mitochondria: keeping reactive oxygen and nitrogen species under control. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:793-807. [PMID: 33245770 DOI: 10.1093/jxb/eraa510] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
Plant mitochondrial respiration involves the operation of various alternative pathways. These pathways participate, both directly and indirectly, in the maintenance of mitochondrial functions though they do not contribute to energy production, being uncoupled from the generation of an electrochemical gradient across the mitochondrial membrane and thus from ATP production. Recent findings suggest that uncoupled respiration is involved in reactive oxygen species (ROS) and nitric oxide (NO) scavenging, regulation, and homeostasis. Here we discuss specific roles and possible functions of uncoupled mitochondrial respiration in ROS and NO metabolism. The mechanisms of expression and regulation of the NDA-, NDB- and NDC-type non-coupled NADH and NADPH dehydrogenases, the alternative oxidase (AOX), and the uncoupling protein (UCP) are examined in relation to their involvement in the establishment of the stable far-from-equilibrium state of plant metabolism. The role of uncoupled respiration in controlling the levels of ROS and NO as well as inducing signaling events is considered. Secondary functions of uncoupled respiration include its role in protection from stress factors and roles in biosynthesis and catabolism. It is concluded that uncoupled mitochondrial respiration plays an important role in providing rapid adaptation of plants to changing environmental factors via regulation of ROS and NO.
Collapse
Affiliation(s)
- Vasily N Popov
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, Voronezh, Russia
- Voronezh State University of Engineering Technologies, Voronezh, Russia
| | - Mikhail Y Syromyatnikov
- Department of Genetics, Cytology and Bioengineering, Voronezh State University, Voronezh, Russia
- Voronezh State University of Engineering Technologies, Voronezh, Russia
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Subhra Chakraborty
- National Institute for Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, India
| | | | - Abir U Igamberdiev
- Department of Biology, Memorial University of Newfoundland, St John's, NL, Canada
| |
Collapse
|
20
|
Zafari S, Vanlerberghe GC, Igamberdiev AU. Nitric Oxide Turnover Under Hypoxia Results in the Rapid Increased Expression of the Plastid-Localized Phosphorylated Pathway of Serine Biosynthesis. FRONTIERS IN PLANT SCIENCE 2021; 12:780842. [PMID: 35173748 PMCID: PMC8841671 DOI: 10.3389/fpls.2021.780842] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 12/28/2021] [Indexed: 05/03/2023]
Abstract
The plant mitochondrial electron transport chain influences carbon and nitrogen metabolism under near anoxic conditions through its involvement in the phytoglobin-nitric oxide cycle, where the respiratory chain reduces nitrite to nitric oxide (NO), followed by NO conversion to nitrate by class 1 phytoglobin. Wild type (WT) and transgenic tobacco (Nicotiana tabacum L.) with differing amounts of alternative oxidase (AOX) were used to manipulate NO generation under hypoxia, and to examine whether this in turn influenced the gene expression of two stress-related amino acid biosynthetic pathways, the plastid-localized phosphorylated pathway of serine biosynthesis (PPSB), and the γ-aminobutyric acid (GABA) shunt. Under hypoxia, leaf NO emission rate was highest in AOX overexpressors and lowest in AOX knockdowns, with WT showing an intermediate rate. In turn, the rate of NO emission correlated with the degree to which amino acids accumulated. This amino acid accumulation was associated with the increased expression of the enzymes of the stress-related amino acid biosynthetic pathways. However, induction of the PPSB occurred much earlier than the GABA shunt. This work shows that high rates of NO turnover associate with rapid gene induction of the PPSB, establishing a clear link between this pathway and the maintenance of carbon, nitrogen and energy metabolism under hypoxia.
Collapse
Affiliation(s)
- Somaieh Zafari
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Greg C. Vanlerberghe
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
- Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, Canada
| | - Abir U. Igamberdiev
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL, Canada
- *Correspondence: Abir U. Igamberdiev,
| |
Collapse
|
21
|
Romero-Aguilar L, Cárdenas-Monroy C, Garrido-Bazán V, Aguirre J, Guerra-Sánchez G, Pardo JP. On the use of n-octyl gallate and salicylhydroxamic acid to study the alternative oxidase role. Arch Biochem Biophys 2020; 694:108603. [PMID: 32986977 DOI: 10.1016/j.abb.2020.108603] [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: 07/19/2020] [Revised: 08/28/2020] [Accepted: 09/24/2020] [Indexed: 10/23/2022]
Abstract
The alternative oxidase (AOX) catalyzes the transfer of electrons from ubiquinol to oxygen without the translocation of protons across the inner mitochondrial membrane. This enzyme has been proposed to participate in the regulation of cell growth, sporulation, yeast-mycelium transition, resistance to reactive oxygen species, infection, and production of secondary metabolites. Two approaches have been used to evaluate AOX function: incubation of cells for long periods of time with AOX inhibitors or deletion of AOX gene. However, AOX inhibitors might have different targets. To test non-specific effects of n-octyl gallate (nOg) and salicylhydroxamic acid (SHAM) on fungal physiology we measured the growth and respiratory capacity of two fungal strains lacking (Ustilago maydis-Δaox and Saccharomyces cerevisiae) and three species containing the AOX gene (U. maydis WT, Debaryomyces hansenii, and Aspergillus nidulans). For U. maydis, a strong inhibition of growth and respiratory capacity by SHAM was observed, regardless of the presence of AOX. Similarly, A. nidulans mycelial growth was inhibited by low concentrations of nOg independently of AOX expression. In contrast, these inhibitors had no effect or had a minor effect on S. cerevisiae and D. hansenii growth. These results show that nOg and SHAM have AOX independent effects which vary in different microorganisms, indicating that studies based on long-term incubation of cells with these inhibitors should be considered as inconclusive.
Collapse
Affiliation(s)
- Lucero Romero-Aguilar
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Christian Cárdenas-Monroy
- Ciencia Forense, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Verónica Garrido-Bazán
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Jesus Aguirre
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Guadalupe Guerra-Sánchez
- Departamento de Microbiología, Laboratorio de Bioquímica y Biotecnología de Hongos, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Carpio y Plan de Ayala S/N., Miguel Hidalgo, 11350, Ciudad de México, Mexico
| | - Juan Pablo Pardo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico.
| |
Collapse
|
22
|
Vanlerberghe GC, Dahal K, Alber NA, Chadee A. Photosynthesis, respiration and growth: A carbon and energy balancing act for alternative oxidase. Mitochondrion 2020; 52:197-211. [PMID: 32278748 DOI: 10.1016/j.mito.2020.04.001] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/28/2020] [Accepted: 04/06/2020] [Indexed: 12/26/2022]
Abstract
This review summarizes knowledge of alternative oxidase, a mitochondrial electron transport chain component that lowers the ATP yield of plant respiration. Analysis of mutant and transgenic plants has established that alternative oxidase activity supports leaf photosynthesis. The interaction of alternative oxidase respiration with chloroplast metabolism is important under conditions that challenge energy and/or carbon balance in the photosynthetic cell. Under such conditions, alternative oxidase provides an extra-chloroplastic means to optimize the status of chloroplast energy pools (ATP, NADPH) and to manage cellular carbohydrate pools in response to changing rates of carbon fixation and carbon demand for growth and maintenance. Transcriptional and post-translational mechanisms ensure that alternative oxidase can respond effectively when carbon and energy balance are being challenged. This function appears particularly significant under abiotic stress conditions such as water deficit, high salinity, or temperature extremes. Under such conditions, alternative oxidase respiration positively affects growth and stress tolerance, despite it lowering the energy yield and carbon use efficiency of respiration. In part, this beneficial effect relates to the ability of alternative oxidase respiration to prevent excessive reactive oxygen species generation in both mitochondria and chloroplasts. Recent evidence suggests that alternative oxidase respiration is an interesting target for crop improvement.
Collapse
Affiliation(s)
- Greg C Vanlerberghe
- Department of Biological Sciences, and Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada.
| | - Keshav Dahal
- Fredericton Research and Development Centre, Agriculture and Agri-Food Canada, 850 Lincoln Road, P.O. Box 20280, Fredericton, New Brunswick E3B4Z7, Canada
| | - Nicole A Alber
- Department of Biological Sciences, and Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada
| | - Avesh Chadee
- Department of Biological Sciences, and Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada
| |
Collapse
|
23
|
Garmash EV, Velegzhaninov IO, Ermolina KV, Rybak AV, Malyshev RV. Altered levels of AOX1a expression result in changes in metabolic pathways in Arabidopsis thaliana plants acclimated to low dose rates of ultraviolet B radiation. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 291:110332. [PMID: 31928662 DOI: 10.1016/j.plantsci.2019.110332] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/28/2019] [Accepted: 11/02/2019] [Indexed: 05/27/2023]
Abstract
UV-B is a damaging component of solar radiation that inevitably reaches the Earth's surface. Plants have developed response mechanisms to adapt to UVB exposure. The alternative oxidase (AOX) catalyzes the ATP-uncoupling cyanide-resistant alternative pathway (AP) in plant mitochondria and is thought to be an important part of the cellular defense network under stress conditions. This study aimed to unravel the poorly understood functional significance of AOX1a induction in Arabidopsis thaliana leaves exposed to ecologically relevant doses of UVB radiation, by comparing wild-type (WT) plants with plants with modified expression of the AOX1a gene, either downregulated by antisense (AS-12) or overexpressed (XX-2). UVB exposure resulted in a phenotypic difference between lines. AOX1a overexpression resulted in the highest induction of AOX1A synthesis and MnSOD activity, and the lowest ROS level without pronounced changes in the phenotype relative to other genotypes. In AS-12 plants, expression of the majority of the genes encoding AOX was detected, other non-phosphorylating pathway components and antioxidant enzymes increased along with anthocyanin accumulation in leaves, and the ROS content was lower than in the WT. In addition to the expected AOX1 protein size (34 kDa), an AOX1 30 kDa band appeared under UVB exposure in all genotypes. However, in AS-12, the alterations in the transcript level and in the abundance of AOX1 protein isoforms induced by UVB could not fully functionally compensate for the lack of AOX1A. This was confirmed by the observed low AP capacity and increased levels of the oxidized form of ascorbate. These results highlight the importance of AOX in plant response to UVB for the control of a balanced metabolism, and indicate that AOX1a plays a key role in the regulation of the stress response.
Collapse
Affiliation(s)
- Elena V Garmash
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia.
| | - Ilya O Velegzhaninov
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| | - Ksenia V Ermolina
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| | - Anna V Rybak
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| | - Ruslan V Malyshev
- Institute of Biology, Komi Scientific Centre, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia
| |
Collapse
|
24
|
Yoshioka I, Kobayashi K, Kirimura K. Overexpression of the gene encoding alternative oxidase for enhanced glucose consumption in oxalic acid producing Aspergillus niger expressing oxaloacetate hydrolase gene. J Biosci Bioeng 2020; 129:172-176. [DOI: 10.1016/j.jbiosc.2019.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/13/2019] [Accepted: 08/28/2019] [Indexed: 10/25/2022]
|
25
|
Jayawardhane J, Cochrane DW, Vyas P, Bykova NV, Vanlerberghe GC, Igamberdiev AU. Roles for Plant Mitochondrial Alternative Oxidase Under Normoxia, Hypoxia, and Reoxygenation Conditions. FRONTIERS IN PLANT SCIENCE 2020; 11:566. [PMID: 32499803 PMCID: PMC7243820 DOI: 10.3389/fpls.2020.00566] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 04/16/2020] [Indexed: 05/19/2023]
Abstract
Alternative oxidase (AOX) is a non-energy conserving terminal oxidase in the plant mitochondrial electron transport chain (ETC) that has a lower affinity for oxygen than does cytochrome (cyt) oxidase. To investigate the role(s) of AOX under different oxygen conditions, wild-type (WT) Nicotiana tabacum plants were compared with AOX knockdown and overexpression plants under normoxia, hypoxia (near-anoxia), and during a reoxygenation period following hypoxia. Paradoxically, under all the conditions tested, the AOX amount across plant lines correlated positively with leaf energy status (ATP/ADP ratio). Under normoxia, AOX was important to maintain respiratory carbon flow, to prevent the mitochondrial generation of superoxide and nitric oxide (NO), to control lipid peroxidation and protein S-nitrosylation, and possibly to reduce the inhibition of cyt oxidase by NO. Under hypoxia, AOX was again important in preventing superoxide generation and lipid peroxidation, but now contributed positively to NO amount. This may indicate an ability of AOX to generate NO under hypoxia, similar to the nitrite reductase activity of cyt oxidase under hypoxia. Alternatively, it may indicate that AOX activity simply reduces the amount of superoxide scavenging of NO, by reducing the availability of superoxide. The amount of inactivation of mitochondrial aconitase during hypoxia was also dependent upon AOX amount, perhaps through its effects on NO amount, and this influenced carbon flow under hypoxia. Finally, AOX was particularly important in preventing nitro-oxidative stress during the reoxygenation period, thereby contributing positively to the recovery of energy status following hypoxia. Overall, the results suggest that AOX plays a beneficial role in low oxygen metabolism, despite its lower affinity for oxygen than cytochrome oxidase.
Collapse
Affiliation(s)
| | - Devin W. Cochrane
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Poorva Vyas
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Natalia V. Bykova
- Morden Research and Development Centre, Agriculture and Agri-Food Canada, Morden, MB, Canada
| | - Greg C. Vanlerberghe
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
- Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, Canada
| | - Abir U. Igamberdiev
- Department of Biology, Memorial University of Newfoundland, St. John’s, NL, Canada
- *Correspondence: Abir U. Igamberdiev,
| |
Collapse
|
26
|
Alber NA, Vanlerberghe GC. Signaling interactions between mitochondria and chloroplasts in Nicotiana tabacum leaf. PHYSIOLOGIA PLANTARUM 2019; 167:188-204. [PMID: 30467859 DOI: 10.1111/ppl.12879] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 11/15/2018] [Indexed: 06/09/2023]
Abstract
Research has begun to elucidate the signal transduction pathway(s) that control cellular responses to changes in mitochondrial status. Important tools in such studies are chemical inhibitors used to initiate mitochondrial dysfunction. This study compares the effect of different inhibitors and treatment conditions on the transcript amount of nuclear genes specifically responsive to mitochondrial dysfunction in leaf of Nicotiana tabacum L. cv. Petit Havana. The Complex III inhibitors antimycin A (AA) and myxothiazol (MYXO), and the Complex V inhibitor oligomycin (OLIGO), each increased the transcript amount of the mitochondrial dysfunction genes. Transcript responses to OLIGO were greater during treatment in the dark than in the light, and the dark treatment resulted in cell death. In the dark, transcript responses to AA and MYXO were similar to one another, despite MYXO leading to cell death. In the light, transcript responses to AA and MYXO diverged, despite cell viability remaining high with either inhibitor. This divergent response may be due to differential signaling from the chloroplast because only AA also inhibited cyclic electron transport, resulting in a strong acceptor-side limitation in photosystem I. In the light, chemical inhibition of chloroplast electron transport reduced transcript responses to AA, while having no effect on the response to MYXO, and increasing the response to OLIGO. Hence, when studying mitochondrial dysfunction signaling, different inhibitor and treatment combinations differentially affect linked processes (e.g. chloroplast function and cell fate) that then contribute to measured responses. Therefore, inhibitor and treatment conditions should be chosen to align with specific study goals.
Collapse
Affiliation(s)
- Nicole A Alber
- Department of Biological Sciences, Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, Ontario, M1C 1A4, Canada
| | - Greg C Vanlerberghe
- Department of Biological Sciences, Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, Ontario, M1C 1A4, Canada
| |
Collapse
|
27
|
Turk H. Chitosan-induced enhanced expression and activation of alternative oxidase confer tolerance to salt stress in maize seedlings. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 141:415-422. [PMID: 31229926 DOI: 10.1016/j.plaphy.2019.06.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 05/18/2023]
Abstract
This study aimed to investigate the possible alleviating effect of chitosan on salt-induced growth retardation and oxidative stress and to elucidate whether this effect is linked to activation of mitochondrial respiration on the basis of alternative respiration in maize seedlings. Salt stress significantly reduced root length and plant height in comparison to the control, whereas foliar application of chitosan ameliorated the adverse effect of salinity to a certain degree. Moreover, chitosan resulted in plant growth promotion as compared to unstressed seedlings. The separate applications of chitosan and salt had a stimulatory effect on the activities of antioxidant enzymes; however, combined application of chitosan and salt were more effective than that of chitosan or salt alone. Similarly, mitochondrial total respiration rate (Vt) and alternative respiration capacity (Valt) were increased by separate applications of chitosan and salt; however, the combination of chitosan and salt gave the highest values for these parameters. The highest values of Valt/Vt was recorded at seedlings treated with salt plus chitosan. Similarly, cytochrome respiration capacity was also increased by chitosan in both stress-free and stressed conditions. In addition, AOX1, encoding alternative oxidase, was significantly upregulated by chitosan and/or salt. The maximum transcript level was recorded at seedlings treated with salt plus chitosan. Chitosan also significantly decreased superoxide anion and hydrogen peroxide contents and lipid peroxidation level under normal and the stressed conditions. These results suggest that the mitigating effect of chitosan on salt stress is linked to activation of alternative respiration at biochemical and molecular level.
Collapse
Affiliation(s)
- Hulya Turk
- East Anatolian High Technology Application and Research Center, Ataturk University, Erzurum, Turkey.
| |
Collapse
|
28
|
Sircar S, Parekh N. Meta-analysis of drought-tolerant genotypes in Oryza sativa: A network-based approach. PLoS One 2019; 14:e0216068. [PMID: 31059518 PMCID: PMC6502313 DOI: 10.1371/journal.pone.0216068] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/12/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Drought is a severe environmental stress. It is estimated that about 50% of the world rice production is affected mainly by drought. Apart from conventional breeding strategies to develop drought-tolerant crops, innovative computational approaches may provide insights into the underlying molecular mechanisms of stress response and identify drought-responsive markers. Here we propose a network-based computational approach involving a meta-analytic study of seven drought-tolerant rice genotypes under drought stress. RESULTS Co-expression networks enable large-scale analysis of gene-pair associations and tightly coupled clusters that may represent coordinated biological processes. Considering differentially expressed genes in the co-expressed modules and supplementing external information such as resistance/tolerance QTLs, transcription factors, network-based topological measures, we identify and prioritize drought-adaptive co-expressed gene modules and potential candidate genes. Using the candidate genes that are well-represented across the datasets as 'seed' genes, two drought-specific protein-protein interaction networks (PPINs) are constructed with up- and down-regulated genes. Cluster analysis of the up-regulated PPIN revealed ABA signalling pathway as a central process in drought response with a probable crosstalk with energy metabolic processes. Tightly coupled gene clusters representing up-regulation of core cellular respiratory processes and enhanced degradation of branched chain amino acids and cell wall metabolism are identified. Cluster analysis of down-regulated PPIN provides a snapshot of major processes associated with photosynthesis, growth, development and protein synthesis, most of which are shut down during drought. Differential regulation of phytohormones, e.g., jasmonic acid, cell wall metabolism, signalling and posttranslational modifications associated with biotic stress are elucidated. Functional characterization of topologically important, drought-responsive uncharacterized genes that may play a role in important processes such as ABA signalling, calcium signalling, photosynthesis and cell wall metabolism is discussed. Further transgenic studies on these genes may help in elucidating their biological role under stress conditions. CONCLUSION Currently, a large number of resources for rice functional genomics exist which are mostly underutilized by the scientific community. In this study, a computational approach integrating information from various resources such as gene co-expression networks, protein-protein interactions and pathway-level information is proposed to provide a systems-level view of complex drought-responsive processes across the drought-tolerant genotypes.
Collapse
Affiliation(s)
- Sanchari Sircar
- Centre for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Hyderabad, India
| | - Nita Parekh
- Centre for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Hyderabad, India
- * E-mail:
| |
Collapse
|
29
|
Hao J, Li X, Xu G, Huo Y, Yang H. Exogenous progesterone treatment alleviates chilling injury in postharvest banana fruit associated with induction of alternative oxidase and antioxidant defense. Food Chem 2019; 286:329-337. [PMID: 30827615 DOI: 10.1016/j.foodchem.2019.02.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 01/25/2019] [Accepted: 02/06/2019] [Indexed: 10/27/2022]
Abstract
The effects of exogenous progesterone (PROG) on chilling injury (CI) in postharvest banana fruit were investigated. Concentration screening tests showed that 10-5 mol/l PROG was most effective in reducing CI in banana fruit stored for 25 d at 5 ± 1 °C, but did not markly increase PROG content of pulps. This PROG treatment significantly reduced the electrolyte leakage, levels of malondialdehyde, O2- production rate and H2O2 contents in banana compared with control fruit. The PROG treatment caused an early induction of alternative oxidase (AOX) at the transcript and protein level to reduce the generation of O2- and H2O2. PROG treatment also enhanced the transcript levels and activities of antioxidant enzymes and maintained higher levels of reduced glutathione and ascorbic acid than the control fruit. These results suggested that PROG attenuating CI in banana fruit may be attributed to the induction of AOX and the improvement of enzyme and non-enzymatic antioxidant defenses.
Collapse
Affiliation(s)
- Jiashi Hao
- School of Agriculture and Food Science, Zhejiang A & F University, Wusu Street # 666, Lin'an District, Hangzhou 311300, People's Republic of China; College of Food Science and Engineering, Shanxi Agricultural University, Taigu County, Shanxi 030801, People's Republic of China
| | - Xia Li
- School of Agriculture and Food Science, Zhejiang A & F University, Wusu Street # 666, Lin'an District, Hangzhou 311300, People's Republic of China
| | - Guangzhi Xu
- School of Agriculture and Food Science, Zhejiang A & F University, Wusu Street # 666, Lin'an District, Hangzhou 311300, People's Republic of China
| | - Yanrong Huo
- School of Agriculture and Food Science, Zhejiang A & F University, Wusu Street # 666, Lin'an District, Hangzhou 311300, People's Republic of China
| | - Huqing Yang
- School of Agriculture and Food Science, Zhejiang A & F University, Wusu Street # 666, Lin'an District, Hangzhou 311300, People's Republic of China.
| |
Collapse
|
30
|
Kaye Y, Huang W, Clowez S, Saroussi S, Idoine A, Sanz-Luque E, Grossman AR. The mitochondrial alternative oxidase from Chlamydomonas reinhardtii enables survival in high light. J Biol Chem 2018; 294:1380-1395. [PMID: 30510139 DOI: 10.1074/jbc.ra118.004667] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/24/2018] [Indexed: 01/07/2023] Open
Abstract
Photosynthetic organisms often experience extreme light conditions that can cause hyper-reduction of the chloroplast electron transport chain, resulting in oxidative damage. Accumulating evidence suggests that mitochondrial respiration and chloroplast photosynthesis are coupled when cells are absorbing high levels of excitation energy. This coupling helps protect the cells from hyper-reduction of photosynthetic electron carriers and diminishes the production of reactive oxygen species (ROS). To examine this cooperative protection, here we characterized Chlamydomonas reinhardtii mutants lacking the mitochondrial alternative terminal respiratory oxidases, CrAOX1 and CrAOX2. Using fluorescent fusion proteins, we experimentally demonstrated that both enzymes localize to mitochondria. We also observed that the mutant strains were more sensitive than WT cells to high light under mixotrophic and photoautotrophic conditions, with the aox1 strain being more sensitive than aox2 Additionally, the lack of CrAOX1 increased ROS accumulation, especially in very high light, and damaged the photosynthetic machinery, ultimately resulting in cell death. These findings indicate that the Chlamydomonas AOX proteins can participate in acclimation of C. reinhardtii cells to excess absorbed light energy. They suggest that when photosynthetic electron carriers are highly reduced, a chloroplast-mitochondria coupling allows safe dissipation of photosynthetically derived electrons via the reduction of O2 through AOX (especially AOX1)-dependent mitochondrial respiration.
Collapse
Affiliation(s)
- Yuval Kaye
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305.
| | - Weichao Huang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Sophie Clowez
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Shai Saroussi
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Adam Idoine
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Emanuel Sanz-Luque
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| |
Collapse
|
31
|
Wanniarachchi VR, Dametto L, Sweetman C, Shavrukov Y, Day DA, Jenkins CLD, Soole KL. Alternative Respiratory Pathway Component Genes (AOX and ND) in Rice and Barley and Their Response to Stress. Int J Mol Sci 2018; 19:E915. [PMID: 29558397 PMCID: PMC5877776 DOI: 10.3390/ijms19030915] [Citation(s) in RCA: 29] [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: 02/14/2018] [Revised: 03/15/2018] [Accepted: 03/16/2018] [Indexed: 11/24/2022] Open
Abstract
Plants have a non-energy conserving bypass of the classical mitochondrial cytochrome c pathway, known as the alternative respiratory pathway (AP). This involves type II NAD(P)H dehydrogenases (NDs) on both sides of the mitochondrial inner membrane, ubiquinone, and the alternative oxidase (AOX). The AP components have been widely characterised from Arabidopsis, but little is known for monocot species. We have identified all the genes encoding components of the AP in rice and barley and found the key genes which respond to oxidative stress conditions. In both species, AOX is encoded by four genes; in rice OsAOX1a, 1c, 1d and 1e representing four clades, and in barley, HvAOX1a, 1c, 1d1 and 1d2, but no 1e. All three subfamilies of plant ND genes, NDA, NDB and NDC are present in both rice and barley, but there are fewer NDB genes compared to Arabidopsis. Cyanide treatment of both species, along with salt treatment of rice and drought treatment of barley led to enhanced expression of various AP components; there was a high level of co-expression of AOX1a and AOX1d, along with NDB3 during the stress treatments, reminiscent of the co-expression that has been well characterised in Arabidopsis for AtAOX1a and AtNDB2.
Collapse
Affiliation(s)
- Vajira R Wanniarachchi
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| | - Lettee Dametto
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| | - Crystal Sweetman
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| | - Yuri Shavrukov
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| | - David A Day
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| | - Colin L D Jenkins
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| | - Kathleen L Soole
- College of Science and Engineering, Flinders University of South Australia, GPO Box 5100, Adelaide, SA 5001, Australia.
| |
Collapse
|
32
|
Rurek M, Czołpińska M, Pawłowski TA, Krzesiński W, Spiżewski T. Cold and Heat Stress Diversely Alter Both Cauliflower Respiration and Distinct Mitochondrial Proteins Including OXPHOS Components and Matrix Enzymes. Int J Mol Sci 2018; 19:ijms19030877. [PMID: 29547512 PMCID: PMC5877738 DOI: 10.3390/ijms19030877] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/07/2018] [Accepted: 03/09/2018] [Indexed: 12/11/2022] Open
Abstract
Complex proteomic and physiological approaches for studying cold and heat stress responses in plant mitochondria are still limited. Variations in the mitochondrial proteome of cauliflower (Brassica oleracea var. botrytis) curds after cold and heat and after stress recovery were assayed by two-dimensional polyacrylamide gel electrophoresis (2D PAGE) in relation to mRNA abundance and respiratory parameters. Quantitative analysis of the mitochondrial proteome revealed numerous stress-affected protein spots. In cold, major downregulations in the level of photorespiratory enzymes, porine isoforms, oxidative phosphorylation (OXPHOS) and some low-abundant proteins were observed. In contrast, carbohydrate metabolism enzymes, heat-shock proteins, translation, protein import, and OXPHOS components were involved in heat response and recovery. Several transcriptomic and metabolic regulation mechanisms are also suggested. Cauliflower plants appeared less susceptible to heat; closed stomata in heat stress resulted in moderate photosynthetic, but only minor respiratory impairments, however, photosystem II performance was unaffected. Decreased photorespiration corresponded with proteomic alterations in cold. Our results show that cold and heat stress not only operate in diverse modes (exemplified by cold-specific accumulation of some heat shock proteins), but exert some associations at molecular and physiological levels. This implies a more complex model of action of investigated stresses on plant mitochondria.
Collapse
Affiliation(s)
- Michał Rurek
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Umultowska 89, 61-614 Poznań, Poland.
| | - Magdalena Czołpińska
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Umultowska 89, 61-614 Poznań, Poland.
| | | | - Włodzimierz Krzesiński
- Department of Vegetable Crops, Poznan University of Life Sciences, Dąbrowskiego 159, 60-594 Poznań, Poland.
| | - Tomasz Spiżewski
- Department of Vegetable Crops, Poznan University of Life Sciences, Dąbrowskiego 159, 60-594 Poznań, Poland.
| |
Collapse
|
33
|
Bali S, Kaur P, Sharma A, Ohri P, Bhardwaj R, Alyemeni MN, Wijaya L, Ahmad P. Jasmonic acid-induced tolerance to root-knot nematodes in tomato plants through altered photosynthetic and antioxidative defense mechanisms. PROTOPLASMA 2018; 255:471-484. [PMID: 28905119 DOI: 10.1007/s00709-017-1160-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/28/2017] [Indexed: 05/04/2023]
Abstract
Plant parasitic nematodes cause severe damage to cultivated crops globally. Management of nematode population is a major concern as chemicals used as nematicides have negative impact on the environment. Natural plant products can be safely used for the control of nematodes. Among various plant metabolites, plant hormones play an essential role in developmental and physiological processes and also assist the plants to encounter stressful conditions. Keeping this in mind, the present study was designed to evaluate the effect of jasmonic acid (JA) on the growth, pigments, polyphenols, antioxidants, osmolytes, and organic acids under nematode infection in tomato seedlings. It was observed that nematode inoculation reduced the growth of seedlings. Treatment with JA improved root growth (32.79%), total chlorophylls (71.51%), xanthophylls (94.63%), anthocyanins (37.5%), and flavonoids content (21.11%) when compared to inoculated seedlings alone. The JA application enhanced the total antioxidant capacity (lipid- and water-soluble antioxidants) by 38.23 and 34.37%, respectively, in comparison to infected seedlings. Confocal studies revealed that there was higher accumulation of glutathione in hormone-treated seedlings under nematode infection. Treatment with JA increased total polyphenols content (74.56%) in comparison to nematode-infested seedlings. JA-treated seedlings also enhanced osmolyte and organic acid contents under nematode stress. Overall, treatment with JA improved growth, enhanced pigment levels, modulated antioxidant content, and enhanced osmolyte and organic acid content in nematode-infected seedlings.
Collapse
Affiliation(s)
- Shagun Bali
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, 143005, India
| | - Parminder Kaur
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, 143005, India
| | - Anket Sharma
- Department of Botany, DAV University, Sarmastpur, Jalandhar, 144012, India
| | - Puja Ohri
- Department of Zoology, Guru Nanak Dev University, Amritsar, Punjab, 143005, India
| | - Renu Bhardwaj
- Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, Punjab, 143005, India.
| | - M N Alyemeni
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Leonard Wijaya
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Parvaiz Ahmad
- Department of Botany and Microbiology, Faculty of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
- Department of Botany, S.P. College, Srinagar, Jammu and Kashmir, 190001, India.
| |
Collapse
|
34
|
Dahal K, Vanlerberghe GC. Improved chloroplast energy balance during water deficit enhances plant growth: more crop per drop. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1183-1197. [PMID: 29281082 PMCID: PMC6018952 DOI: 10.1093/jxb/erx474] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 12/07/2017] [Indexed: 05/02/2023]
Abstract
The non-energy-conserving alternative oxidase (AOX) respiration of plant mitochondria is known to interact with chloroplast photosynthesis. This may have consequences for growth, particularly under sub-optimal conditions when energy imbalances can impede photosynthesis. This hypothesis was tested by comparing the metabolism and growth of wild-type Nicotiana tabacum with that of AOX knockdown and overexpression lines during a prolonged steady-state mild to moderate water deficit. Under moderate water deficit, the AOX amount was an important determinant of the rate of both mitochondrial respiration in the light and net photosynthetic CO2 assimilation (A) at the growth irradiance. In particular, AOX respiration was necessary to maintain optimal proton and electron fluxes at the chloroplast thylakoid membrane, which in turn prevented a water-deficit-induced biochemical limitation of photosynthesis. As a result of differences in A, AOX overexpressors gained more biomass and knockdowns gained less biomass than wild-type during moderate water deficit. Biomass partitioning also differed, with the overexpressors having a higher percentage, and the knockdowns having a lower percentage, of total above-ground biomass in reproductive tissue than wild-type. The results establish that improving chloroplast energy balance by using a non-energy-conserving respiratory electron sink can increase photosynthesis and growth during prolonged water deficit.
Collapse
Affiliation(s)
- Keshav Dahal
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Greg C Vanlerberghe
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, Ontario, Canada
| |
Collapse
|
35
|
Karami-Moalem S, Maali-Amiri R, Kazemi-Shahandashti SS. Effect of cold stress on oxidative damage and mitochondrial respiratory properties in chickpea. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 122:31-39. [PMID: 29172103 DOI: 10.1016/j.plaphy.2017.11.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/17/2017] [Accepted: 11/17/2017] [Indexed: 05/02/2023]
Abstract
The present work aimed to characterize some of the mitochondrial and defense responses involved in tolerance to cold stress (CS) in tolerant (Sel96Th11439) and sensitive (ILC533) chickpea (Cicer arietinum L.) genotypes. During CS, the tolerant genotype prevented the H2O2 accumulation significantly; led to a decrease in electrolyte leakage index (ELI), which was a sign of relative acclimation of this genotype compared to sensitive one. A significant positive correlation between ELI and H2O2 (r0.01 = 0.86) content confirmed these results. Under cold, a significant increase in the alternative oxidase (AOX) activity was observed in tolerant genotype compared to sensitive one. In parallel, the high activity of superoxide dismutase (SOD) accompanied with catalase (CAT) and ascorbate peroxidase (APX) activities and also the extreme amounts of ascorbate and proline certified the active reactive oxygen species (ROS)-scavenging systems. There was a significant negative correlation between damage indices like H2O2 content and the activity of AOX (r0.01 = -0.79) as well as significant positive correlation between AOX activity with CAT (r0.05 = 0.61), SOD (r0.05 = 0.51) and APX activity (r0.05 = 0.52). The increasing succinate dehydrogenase (CaSDH), CaAOX and cytochrome c oxidase (CaCOX) gene expression showed an enhancing response of respiration under CS in tolerant plants compared to sensitive ones. The increasing trend of phosphoenol pyruvate carboxylase (PEPC) activity in tolerant genotype particularly in the sixth day of CS indicated the recovered performance of metabolism pathways. Therefore, the increase of AOX activity along with other defensive mechanisms could be coordinately related to cold tolerance mechanisms in order to alleviate cold-induced oxidative stress in chickpea.
Collapse
Affiliation(s)
- Samaneh Karami-Moalem
- Department of Agronomy and Plant Breeding, University College of Agriculture and Natural Resources, University of Tehran, 31587-77871, Karaj, Iran
| | - Reza Maali-Amiri
- Department of Agronomy and Plant Breeding, University College of Agriculture and Natural Resources, University of Tehran, 31587-77871, Karaj, Iran.
| | - Seyyedeh-Sanam Kazemi-Shahandashti
- Department of Agronomy and Plant Breeding, University College of Agriculture and Natural Resources, University of Tehran, 31587-77871, Karaj, Iran
| |
Collapse
|
36
|
Alber NA, Sivanesan H, Vanlerberghe GC. The occurrence and control of nitric oxide generation by the plant mitochondrial electron transport chain. PLANT, CELL & ENVIRONMENT 2017; 40:1074-1085. [PMID: 27987212 DOI: 10.1111/pce.12884] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 12/02/2016] [Accepted: 12/05/2016] [Indexed: 05/03/2023]
Abstract
The plant mitochondrial electron transport chain (ETC) is bifurcated such that electrons from ubiquinol are passed to oxygen via the usual cytochrome path or through alternative oxidase (AOX). We previously showed that knockdown of AOX in transgenic tobacco increased leaf concentrations of nitric oxide (NO), implying that an activity capable of generating NO had been effected. Here, we identify the potential source of this NO. Treatment of leaves with antimycin A (AA, Qi -site inhibitor of Complex III) increased NO amount more than treatment with myxothiazol (Myxo, Qo -site inhibitor) despite both being equally effective at inhibiting respiration. Comparison of nitrate-grown wild-type with AOX knockdown and overexpression plants showed a negative correlation between AOX amount and NO amount following AA. Further, Myxo fully negated the ability of AA to increase NO amount. With ammonium-grown plants, neither AA nor Myxo strongly increased NO amount in any plant line. When these leaves were supplied with nitrite alongside the AA or Myxo, then the inhibitor effects across lines mirrored that of nitrate-grown plants. Hence the ETC, likely the Q-cycle of Complex III generates NO from nitrite, and AOX reduces this activity by acting as a non-energy-conserving electron sink upstream of Complex III.
Collapse
Affiliation(s)
- Nicole A Alber
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C1A4, Canada
| | - Hampavi Sivanesan
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C1A4, Canada
| | - Greg C Vanlerberghe
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C1A4, Canada
| |
Collapse
|
37
|
Cárdenas-Monroy CA, Pohlmann T, Piñón-Zárate G, Matus-Ortega G, Guerra G, Feldbrügge M, Pardo JP. The mitochondrial alternative oxidase Aox1 is needed to cope with respiratory stress but dispensable for pathogenic development in Ustilago maydis. PLoS One 2017; 12:e0173389. [PMID: 28273139 PMCID: PMC5342259 DOI: 10.1371/journal.pone.0173389] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 02/20/2017] [Indexed: 12/22/2022] Open
Abstract
The mitochondrial alternative oxidase is an important enzyme that allows respiratory activity and the functioning of the Krebs cycle upon disturbance of the respiration chain. It works as a security valve in transferring excessive electrons to oxygen, thereby preventing potential damage by the generation of harmful radicals. A clear biological function, besides the stress response, has so far convincingly only been shown for plants that use the alternative oxidase to generate heat to distribute volatiles. In fungi it was described that the alternative oxidase is needed for pathogenicity. Here, we investigate expression and function of the alternative oxidase at different stages of the life cycle of the corn pathogen Ustilago maydis (Aox1). Interestingly, expression of Aox1 is specifically induced during the stationary phase suggesting a role at high cell density when nutrients become limiting. Studying deletion strains as well as overexpressing strains revealed that Aox1 is dispensable for normal growth, for cell morphology, for response to temperature stress as well as for filamentous growth and plant pathogenicity. However, during conditions eliciting respiratory stress yeast-like growth as well as hyphal growth is strongly affected. We conclude that Aox1 is dispensable for the normal biology of the fungus but specifically needed to cope with respiratory stress.
Collapse
Affiliation(s)
| | - Thomas Pohlmann
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Department of Biology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Gabriela Piñón-Zárate
- Departamento de Biología Celular y Tisular, Facultad de Medicina, UNAM. Ciudad de México, México
| | - Genaro Matus-Ortega
- Departamento de Bioquímica, Facultad de Medicina, UNAM. Ciudad de México, México
| | - Guadalupe Guerra
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Ciudad de México, México
| | - Michael Feldbrügge
- Institute for Microbiology, Cluster of Excellence on Plant Sciences, Department of Biology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Juan Pablo Pardo
- Departamento de Bioquímica, Facultad de Medicina, UNAM. Ciudad de México, México
| |
Collapse
|
38
|
Dahal K, Martyn GD, Alber NA, Vanlerberghe GC. Coordinated regulation of photosynthetic and respiratory components is necessary to maintain chloroplast energy balance in varied growth conditions. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:657-671. [PMID: 28011719 PMCID: PMC5441918 DOI: 10.1093/jxb/erw469] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Mitochondria have a non-energy-conserving alternative oxidase (AOX) proposed to support photosynthesis, perhaps by promoting energy balance under varying growth conditions. To investigate this, wild-type (WT) Nicotiana tabacum were compared with AOX knockdown and overexpression lines. In addition, the amount of AOX protein in WT plants was compared with that of chloroplast light-harvesting complex II (LHCB2), whose amount is known to respond to chloroplast energy status. With increased growth irradiance, WT leaves maintained higher rates of respiration in the light (RL), but no differences in RL or photosynthesis were seen between the WT and transgenic lines, suggesting that, under non-stress conditions, AOX was not critical for leaf metabolism, regardless of growth irradiance. However, under drought, the AOX amount became an important determinant of RL, which in turn was an important determinant of chloroplast energy balance (measured as photosystem II excitation pressure, EP), and photosynthetic performance. In the WT, the AOX amount increased and the LHCB2 amount decreased with increased growth irradiance or drought severity. These changes in protein amounts correlated strongly, in opposing ways, with growth EP. This suggests that a signal deriving from the photosynthetic electron transport chain status coordinately controls the amounts of AOX and LHCB2, which then both contribute to maintaining chloroplast energy balance, particularly under stress conditions.
Collapse
Affiliation(s)
- Keshav Dahal
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Military Trail, Toronto,
ON, Canada
| | - Greg D Martyn
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Military Trail, Toronto,
ON, Canada
| | - Nicole A Alber
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Military Trail, Toronto,
ON, Canada
| | - Greg C Vanlerberghe
- Department of Biological Sciences and Department of Cell and Systems Biology, University of Toronto Scarborough, Military Trail, Toronto,
ON, Canada
| |
Collapse
|
39
|
Dinakar C, Vishwakarma A, Raghavendra AS, Padmasree K. Alternative Oxidase Pathway Optimizes Photosynthesis During Osmotic and Temperature Stress by Regulating Cellular ROS, Malate Valve and Antioxidative Systems. FRONTIERS IN PLANT SCIENCE 2016; 7:68. [PMID: 26904045 PMCID: PMC4747084 DOI: 10.3389/fpls.2016.00068] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 01/15/2016] [Indexed: 05/19/2023]
Abstract
The present study reveals the importance of alternative oxidase (AOX) pathway in optimizing photosynthesis under osmotic and temperature stress conditions in the mesophyll protoplasts of Pisum sativum. The responses of photosynthesis and respiration were monitored at saturating light intensity of 1000 μmoles m(-2) s(-1) at 25°C under a range of sorbitol concentrations from 0.4 to 1.0 M to induce hyper-osmotic stress and by varying the temperature of the thermo-jacketed pre-incubation chamber from 25 to 10°C to impose sub-optimal temperature stress. Compared to controls (0.4 M sorbitol and 25°C), the mesophyll protoplasts showed remarkable decrease in NaHCO3-dependent O2 evolution (indicator of photosynthetic carbon assimilation), under both hyper-osmotic (1.0 M sorbitol) and sub-optimal temperature stress conditions (10°C), while the decrease in rates of respiratory O2 uptake were marginal. The capacity of AOX pathway increased significantly in parallel to increase in intracellular pyruvate and reactive oxygen species (ROS) levels under both hyper-osmotic stress and sub-optimal temperature stress under the background of saturating light. The ratio of redox couple (Malate/OAA) related to malate valve increased in contrast to the ratio of redox couple (GSH/GSSG) related to antioxidative system during hyper-osmotic stress. Further, the ratio of GSH/GSSG decreased in the presence of sub-optimal temperature, while the ratio of Malate/OAA showed no visible changes. Also, the redox ratios of pyridine nucleotides increased under hyper-osmotic (NADH/NAD) and sub-optimal temperature (NADPH/NADP) stresses, respectively. However, upon restriction of AOX pathway by using salicylhydroxamic acid (SHAM), the observed changes in NaHCO3-dependent O2 evolution, cellular ROS, redox ratios of Malate/OAA, NAD(P)H/NAD(P) and GSH/GSSG were further aggravated under stress conditions with concomitant modulations in NADP-MDH and antioxidant enzymes. Taken together, the results indicated the importance of AOX pathway in optimizing photosynthesis under both hyper-osmotic stress and sub-optimal temperatures. Regulation of ROS through redox couples related to malate valve and antioxidant system by AOX pathway to optimize photosynthesis under these stresses are discussed.
Collapse
Affiliation(s)
- Challabathula Dinakar
- Department of Plant Sciences, School of Life Sciences, University of HyderabadHyderabad, India
- Department of Life Sciences, School of Basic and Applied Sciences, Central University of Tamil NaduThiruvarur, India
| | - Abhaypratap Vishwakarma
- Department of Plant Sciences, School of Life Sciences, University of HyderabadHyderabad, India
| | - Agepati S. Raghavendra
- Department of Plant Sciences, School of Life Sciences, University of HyderabadHyderabad, India
| | - Kollipara Padmasree
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of HyderabadHyderabad, India
- *Correspondence: Kollipara Padmasree, ;
| |
Collapse
|
40
|
Rogov AG, Zvyagilskaya RA. Physiological role of alternative oxidase (from yeasts to plants). BIOCHEMISTRY (MOSCOW) 2016; 80:400-7. [PMID: 25869356 DOI: 10.1134/s0006297915040021] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Mitochondria of all so far studied organisms, with the exception of Archaea, mammals, some yeasts, and protists, contain, along with the classical phosphorylating cytochrome pathway, a so-called cyanide-insensitive alternative oxidase (AOX) localized on the matrix side of the mitochondrial inner membrane, and electron transport through which is not coupled with ATP synthesis and energy accumulation. Mechanisms underlying plentiful functions of AOX in organisms at various levels of organization ranging from yeasts to plants are considered. First and foremost, AOX provides a chance of cell survival after inhibiting the terminal components of the main respiratory chain or losing the ability to synthesize these components. The vitally important role of AOX is obvious in thermogenesis of thermogenic plant organs where it becomes the only terminal oxidase with a very high activity, and the energy of substrate oxidation by this respiratory pathway is converted into heat, thus promoting evaporation of volatile substances attracting pollinating insects. AOX plays a fundamentally significant role in alleviating or preventing oxidative stress, thus ensuring the defense against a wide range of stresses and adverse environmental conditions, such as changes in temperature and light intensities, osmotic stress, drought, and attack by incompatible strains of bacterial pathogens, phytopathogens, or their elicitors. Participation of AOX in pathogen survival during its existence inside the host, in antivirus defense, as well as in metabolic rearrangements in plants during embryogenesis and cell differentiation is described. Examples are given to demonstrate that AOX might be an important tool to overcome the adverse aftereffects of restricted activity of the main respiratory chain in cells and whole animals.
Collapse
Affiliation(s)
- A G Rogov
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, 119071, Russia.
| | | |
Collapse
|
41
|
Zalutskaya Z, Lapina T, Ermilova E. The Chlamydomonas reinhardtii alternative oxidase 1 is regulated by heat stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2015; 97:229-34. [PMID: 26492131 DOI: 10.1016/j.plaphy.2015.10.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 10/03/2015] [Accepted: 10/09/2015] [Indexed: 05/27/2023]
Abstract
The alternative oxidase (AOX) is a non-energy conserving terminal oxidase that has emerged as an important mitochondrial component of the cell stress responses. Although the most studied abiotic condition in relation to Chlamydomonas reinhardtii is high temperature, changes in AOX capacity of the alga were studied only under oxidative stress and cold. To examine whether elevated temperatures affected AOX1 expression, we applied quantitative real-time PCR and pharmaceutical approaches. In this work, we demonstrated a sharp increase in AOX1 transcript and protein abundance under heat stress. Furthermore, C. reinhardtii cells displayed a large increase in alternative respiration in response to high temperature. Feeding with the protein kinase inhibitor staurosporine strongly retarded the AOX1 transcription. Finally, the addition of the calcium chelator EGTA prevented heat-induced AOX1 expression. Together, our results imply that heat-inducible Ca(2+) influx and protein kinase(s) may mediate AOX1 expression at elevated temperatures. Characterization of heat-induced AOX1 regulation in the green alga C. reinhardtii provides a framework for a more complete understanding of the function of this conserved protein.
Collapse
Affiliation(s)
- Zhanneta Zalutskaya
- Lab Adaptation in Microorganisms, Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia
| | - Tatiana Lapina
- Lab Adaptation in Microorganisms, Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia
| | - Elena Ermilova
- Lab Adaptation in Microorganisms, Biological Faculty, Saint-Petersburg State University, Saint-Petersburg, Russia.
| |
Collapse
|
42
|
Zhu F, Deng XG, Xu F, Jian W, Peng XJ, Zhu T, Xi DH, Lin HH. Mitochondrial alternative oxidase is involved in both compatible and incompatible host-virus combinations in Nicotiana benthamiana. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2015; 239:26-35. [PMID: 26398788 DOI: 10.1016/j.plantsci.2015.07.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 07/08/2015] [Accepted: 07/10/2015] [Indexed: 05/27/2023]
Abstract
The alternative oxidase (AOX) functions in the resistance to biotic stress. However, the mechanisms of AOX in the systemic antiviral defense response and N (a typical resistance gene)-mediated resistance to Tobacco mosaic virus (TMV) are elusive. A chemical approach was undertaken to investigate the role of NbAOX in the systemic resistance to RNA viruses. Furthermore, we used a virus-induced gene-silencing (VIGS)-based genetics approach to investigate the function of AOX in the N-mediated resistance to TMV. The inoculation of virus significantly increased the NbAOX transcript and protein levels and the cyanide-resistant respiration in the upper un-inoculated leaves. Pretreatment with potassium cyanide greatly increased the plant's systemic resistance, whereas the application of salicylhydroxamic acid significantly compromised the plant's systemic resistance. Additionally, in NbAOX1a-silenced N-transgenic Nicotiana benthamiana plants, the inoculated leaf collapsed and the movement of TMV into the systemic tissue eventually led to the spreading of HR-PCD and the death of the whole plant. The hypersensitive response marker gene HIN1 was significantly increased in the NbAOX1a-silenced plants. Significant amounts of TMV-CP mRNA and protein were detected in the NbAOX1a-silenced plants but not in the control plants. Overall, evidence is provided that AOX plays important roles in both compatible and incompatible plant-virus combinations.
Collapse
Affiliation(s)
- Feng Zhu
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China; College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, 225009, China
| | - Xing-Guang Deng
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Fei Xu
- Applied Biotechnology Center, Wuhan Bioengineering Insititute, 430415, China
| | - Wei Jian
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Xing-Ji Peng
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Tong Zhu
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - De-Hui Xi
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Hong-Hui Lin
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China.
| |
Collapse
|
43
|
Rogov AG, Sukhanova EI, Uralskaya LA, Aliverdieva DA, Zvyagilskaya RA. Alternative oxidase: distribution, induction, properties, structure, regulation, and functions. BIOCHEMISTRY (MOSCOW) 2015; 79:1615-34. [PMID: 25749168 DOI: 10.1134/s0006297914130112] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The respiratory chain in the majority of organisms with aerobic type metabolism features the concomitant existence of the phosphorylating cytochrome pathway and the cyanide- and antimycin A-insensitive oxidative route comprising a so-called alternative oxidase (AOX) as a terminal oxidase. In this review, the history of AOX discovery is described. Considerable evidence is presented that AOX occurs widely in organisms at various levels of organization and is not confined to the plant kingdom. This enzyme has not been found only in Archaea, mammals, some yeasts and protists. Bioinformatics research revealed the sequences characteristic of AOX in representatives of various taxonomic groups. Based on multiple alignments of these sequences, a phylogenetic tree was constructed to infer their possible evolution. The ways of AOX activation, as well as regulatory interactions between AOX and the main respiratory chain are described. Data are summarized concerning the properties of AOX and the AOX-encoding genes whose expression is either constitutive or induced by various factors. Information is presented on the structure of AOX, its active center, and the ubiquinone-binding site. The principal functions of AOX are analyzed, including the cases of cell survival, optimization of respiratory metabolism, protection against excess of reactive oxygen species, and adaptation to variable nutrition sources and to biotic and abiotic stress factors. It is emphasized that different AOX functions complement each other in many instances and are not mutually exclusive. Examples are given to demonstrate that AOX is an important tool to overcome the adverse aftereffects of restricted activity of the main respiratory chain in cells and whole animals. This is the first comprehensive review on alternative oxidases of various organisms ranging from yeasts and protists to vascular plants.
Collapse
Affiliation(s)
- A G Rogov
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, 119071, Russia.
| | | | | | | | | |
Collapse
|
44
|
Vishwakarma A, Tetali SD, Selinski J, Scheibe R, Padmasree K. Importance of the alternative oxidase (AOX) pathway in regulating cellular redox and ROS homeostasis to optimize photosynthesis during restriction of the cytochrome oxidase pathway in Arabidopsis thaliana. ANNALS OF BOTANY 2015; 116:555-69. [PMID: 26292995 PMCID: PMC4578005 DOI: 10.1093/aob/mcv122] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 03/13/2015] [Accepted: 06/08/2015] [Indexed: 05/17/2023]
Abstract
BACKGROUND AND AIMS The importance of the alternative oxidase (AOX) pathway, particularly AOX1A, in optimizing photosynthesis during de-etiolation, under elevated CO2, low temperature, high light or combined light and drought stress is well documented. In the present study, the role of AOX1A in optimizing photosynthesis was investigated when electron transport through the cytochrome c oxidase (COX) pathway was restricted at complex III. METHODS Leaf discs of wild-type (WT) and aox1a knock-out mutants of Arabidopsis thaliana were treated with antimycin A (AA) under growth-light conditions. To identify the impact of AOX1A deficiency in optimizing photosynthesis, respiratory O2 uptake and photosynthesis-related parameters were measured along with changes in redox couples, reactive oxygen species (ROS), lipid peroxidation and expression levels of genes related to respiration, the malate valve and the antioxidative system. KEY RESULTS In the absence of AA, aox1a knock-out mutants did not show any difference in physiological, biochemical or molecular parameters compared with WT. However, after AA treatment, aox1a plants showed a significant reduction in both respiratory O2 uptake and NaHCO3-dependent O2 evolution. Chlorophyll fluorescence and P700 studies revealed that in contrast to WT, aox1a knock-out plants were incapable of maintaining electron flow in the chloroplastic electron transport chain, and thereby inefficient heat dissipation (low non-photochemical quenching) was observed. Furthermore, aox1a mutants exhibited significant disturbances in cellular redox couples of NAD(P)H and ascorbate (Asc) and consequently accumulation of ROS and malondialdehyde (MDA) content. By contrast, WT plants showed a significant increase in transcript levels of CSD1, CAT1, sAPX, COX15 and AOX1A in contrast to aox1a mutants. CONCLUSIONS These results suggest that AOX1A plays a significant role in sustaining the chloroplastic redox state and energization to optimize photosynthesis by regulating cellular redox homeostasis and ROS generation when electron transport through the COX pathway is disturbed at complex III.
Collapse
Affiliation(s)
- Abhaypratap Vishwakarma
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500 046, India
| | - Sarada Devi Tetali
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500 046, India
| | - Jennifer Selinski
- Department of Plant Physiology, FB5, University of Osnabrück, 49069 Osnabrück, Germany and
| | - Renate Scheibe
- Department of Plant Physiology, FB5, University of Osnabrück, 49069 Osnabrück, Germany and
| | - Kollipara Padmasree
- Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad 500 046, India
| |
Collapse
|
45
|
Pu X, Lv X, Tan T, Fu F, Qin G, Lin H. Roles of mitochondrial energy dissipation systems in plant development and acclimation to stress. ANNALS OF BOTANY 2015; 116:583-600. [PMID: 25987710 PMCID: PMC4577992 DOI: 10.1093/aob/mcv063] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/16/2015] [Accepted: 03/27/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Plants are sessile organisms that have the ability to integrate external cues into metabolic and developmental signals. The cues initiate specific signal cascades that can enhance the tolerance of plants to stress, and these mechanisms are crucial to the survival and fitness of plants. The adaption of plants to stresses is a complex process that involves decoding stress inputs as energy-deficiency signals. The process functions through vast metabolic and/or transcriptional reprogramming to re-establish the cellular energy balance. Members of the mitochondrial energy dissipation pathway (MEDP), alternative oxidases (AOXs) and uncoupling proteins (UCPs), act as energy mediators and might play crucial roles in the adaption of plants to stresses. However, their roles in plant growth and development have been relatively less explored. SCOPE This review summarizes current knowledge about the role of members of the MEDP in plant development as well as recent advances in identifying molecular components that regulate the expression of AOXs and UCPs. Highlighted in particular is a comparative analysis of the expression, regulation and stress responses between AOXs and UCPs when plants are exposed to stresses, and a possible signal cross-talk that orchestrates the MEDP, reactive oxygen species (ROS), calcium signalling and hormone signalling. CONCLUSIONS The MEDP might act as a cellular energy/metabolic mediator that integrates ROS signalling, energy signalling and hormone signalling with plant development and stress accumulation. However, the regulation of MEDP members is complex and occurs at transcriptional, translational, post-translational and metabolic levels. How this regulation is linked to actual fluxes through the AOX/UCP in vivo remains elusive.
Collapse
Affiliation(s)
- Xiaojun Pu
- Ministry of Education Key Laboratory for Bio-Resource & Eco-Environment and Plant Physiology Laboratory, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Xin Lv
- Ministry of Education Key Laboratory for Bio-Resource & Eco-Environment and Plant Physiology Laboratory, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Tinghong Tan
- Ministry of Education Key Laboratory for Bio-Resource & Eco-Environment and Plant Physiology Laboratory, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Faqiong Fu
- Ministry of Education Key Laboratory for Bio-Resource & Eco-Environment and Plant Physiology Laboratory, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Gongwei Qin
- Ministry of Education Key Laboratory for Bio-Resource & Eco-Environment and Plant Physiology Laboratory, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| | - Honghui Lin
- Ministry of Education Key Laboratory for Bio-Resource & Eco-Environment and Plant Physiology Laboratory, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064, China
| |
Collapse
|
46
|
Grabelnych OI, Borovik OA, Tauson EL, Pobezhimova TP, Katyshev AI, Pavlovskaya NS, Koroleva NA, Lyubushkina IV, Bashmakov VY, Popov VN, Borovskii GB, Voinikov VK. Mitochondrial energy-dissipating systems (alternative oxidase, uncoupling proteins, and external NADH dehydrogenase) are involved in development of frost-resistance of winter wheat seedlings. BIOCHEMISTRY (MOSCOW) 2015; 79:506-19. [PMID: 25100008 DOI: 10.1134/s0006297914060030] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Gene expression, protein synthesis, and activities of alternative oxidase (AOX), uncoupling proteins (UCP), adenine nucleotide translocator (ANT), and non-coupled NAD(P)H dehydrogenases (NDex, NDPex, and NDin) were studied in shoots of etiolated winter wheat (Triticum aestivum L.) seedlings after exposure to hardening low positive (2°C for 7 days) and freezing (-2°C for 2 days) temperatures. The cold hardening efficiently increased frost-resistance of the seedlings and decreased the generation of reactive oxygen species (ROS) during further cold shock. Functioning of mitochondrial energy-dissipating systems can represent a mechanism responsible for the decrease in ROS under these conditions. These systems are different in their response to the action of the hardening low positive and freezing temperatures. The functioning of the first system causes induction of AOX and UCP synthesis associated with an increase in electron transfer via AOX in the mitochondrial respiratory chain and also with an increase in the sensitivity of mitochondrial non-phosphorylating respiration to linoleic and palmitic acids. The increase in electron transfer via AOX upon exposure of seedlings to hardening freezing temperature is associated with retention of a high activity of NDex. It seems that NDex but not the NDPex and NDin can play an important role in maintaining the functional state of mitochondria in heterotrophic tissues of plants under the influence of freezing temperatures. The involvement of the mitochondrial energy-dissipating systems and their possible physiological role in the adaptation of winter crops to cold and frost are discussed.
Collapse
Affiliation(s)
- O I Grabelnych
- Siberian Institute of Plant Physiology and Biochemistry, Siberian Division of the Russian Academy of Sciences, Irkutsk, 664033, Russia.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Rurek M, Woyda-Ploszczyca AM, Jarmuszkiewicz W. Biogenesis of mitochondria in cauliflower (Brassica oleracea var. botrytis) curds subjected to temperature stress and recovery involves regulation of the complexome, respiratory chain activity, organellar translation and ultrastructure. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:399-417. [PMID: 25617518 DOI: 10.1016/j.bbabio.2015.01.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 12/05/2014] [Accepted: 01/16/2015] [Indexed: 12/30/2022]
Abstract
The biogenesis of the cauliflower curd mitochondrial proteome was investigated under cold, heat and the recovery. For the first time, two dimensional fluorescence difference gel electrophoresis was used to study the plant mitochondrial complexome in heat and heat recovery. Particularly, changes in the complex I and complex III subunits and import proteins, and the partial disintegration of matrix complexes were observed. The presence of unassembled subunits of ATP synthase was accompanied by impairment in mitochondrial translation of its subunit. In cold and heat, the transcription profiles of mitochondrial genes were uncorrelated. The in-gel activities of respiratory complexes were particularly affected after stress recovery. Despite a general stability of respiratory chain complexes in heat, functional studies showed that their activity and the ATP synthesis yield were affected. Contrary to cold stress, heat stress resulted in a reduced efficiency of oxidative phosphorylation likely due to changes in alternative oxidase (AOX) activity. Stress and stress recovery differently modulated the protein level and activity of AOX. Heat stress induced an increase in AOX activity and protein level, and AOX1a and AOX1d transcript level, while heat recovery reversed the AOX protein and activity changes. Conversely, cold stress led to a decrease in AOX activity (and protein level), which was reversed after cold recovery. Thus, cauliflower AOX is only induced by heat stress. In heat, contrary to the AOX activity, the activity of rotenone-insensitive internal NADH dehydrogenase was diminished. The relevance of various steps of plant mitochondrial biogenesis to temperature stress response and recovery is discussed.
Collapse
Affiliation(s)
- Michal Rurek
- Department of Cellular and Molecular Biology, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614 Poznań, Poland.
| | - Andrzej M Woyda-Ploszczyca
- Department of Bioenergetics, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614 Poznań, Poland
| | - Wieslawa Jarmuszkiewicz
- Department of Bioenergetics, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614 Poznań, Poland
| |
Collapse
|
48
|
Selvaraju TR, Khaza'ai H, Vidyadaran S, Abd Mutalib MS, Vasudevan R. The neuroprotective effects of tocotrienol rich fraction and alpha tocopherol against glutamate injury in astrocytes. Bosn J Basic Med Sci 2014; 14:195-204. [PMID: 25428670 DOI: 10.17305/bjbms.2014.4.91] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 09/12/2014] [Accepted: 09/12/2014] [Indexed: 01/01/2023] Open
Abstract
Tocotrienol rich fraction (TRF) is an extract of palm oil, which consists of 25% alpha tocopherol (α-TCP) and 75% tocotrienols. TRF has been shown to possess potent antioxidant, anti-inflammatory, anticancer, neuroprotection, and cholesterol lowering activities. Glutamate is the main excitatory amino acid neurotransmitter in the central nervous system of mammalian, which can be excitotoxic, and it has been suggested to play a key role in neurodegenerative disorders like Parkinson's and Alzheimer's diseases. In this present study, the effects of vitamin E (TRF and α-TCP) in protecting astrocytes against glutamate injury were elucidated. Astrocytes induced with 180 mM of glutamate lead to significant cell death. However, glutamate mediated cytotoxicity was diminished via pre and post supplementation of TRF and α-TCP. Hence, vitamin E acted as a potent antioxidant agent in recovering mitochondrial injury due to elevated oxidative stress, and enhanced better survivability upon glutamate toxicity.
Collapse
Affiliation(s)
- Thilaga Rati Selvaraju
- Biochemistry Unit, Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, 43400 Selangor, Malaysia.
| | | | | | | | | |
Collapse
|
49
|
Rurek M. Plant mitochondria under a variety of temperature stress conditions. Mitochondrion 2014; 19 Pt B:289-94. [DOI: 10.1016/j.mito.2014.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 02/12/2014] [Accepted: 02/14/2014] [Indexed: 10/25/2022]
|
50
|
Dahal K, Wang J, Martyn GD, Rahimy F, Vanlerberghe GC. Mitochondrial alternative oxidase maintains respiration and preserves photosynthetic capacity during moderate drought in Nicotiana tabacum. PLANT PHYSIOLOGY 2014; 166:1560-74. [PMID: 25204647 PMCID: PMC4226348 DOI: 10.1104/pp.114.247866] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/07/2014] [Indexed: 05/18/2023]
Abstract
The mitochondrial electron transport chain includes an alternative oxidase (AOX) that is hypothesized to aid photosynthetic metabolism, perhaps by acting as an additional electron sink for photogenerated reductant or by dampening the generation of reactive oxygen species. Gas exchange, chlorophyll fluorescence, photosystem I (PSI) absorbance, and biochemical and protein analyses were used to compare respiration and photosynthesis of Nicotiana tabacum 'Petit Havana SR1' wild-type plants with that of transgenic AOX knockdown (RNA interference) and overexpression lines, under both well-watered and moderate drought-stressed conditions. During drought, AOX knockdown lines displayed a lower rate of respiration in the light than the wild type, as confirmed by two independent methods. Furthermore, CO2 and light response curves indicated a nonstomatal limitation of photosynthesis in the knockdowns during drought, relative to the wild type. Also relative to the wild type, the knockdowns under drought maintained PSI and PSII in a more reduced redox state, showed greater regulated nonphotochemical energy quenching by PSII, and displayed a higher relative rate of cyclic electron transport around PSI. The origin of these differences may lie in the chloroplast ATP synthase amount, which declined dramatically in the knockdowns in response to drought. None of these effects were seen in plants overexpressing AOX. The results show that AOX is necessary to maintain mitochondrial respiration during moderate drought. In its absence, respiration rate slows and the lack of this electron sink feeds back on the photosynthetic apparatus, resulting in a loss of chloroplast ATP synthase that then limits photosynthetic capacity.
Collapse
Affiliation(s)
- Keshav Dahal
- Departments of Biological Sciences and Cell and Systems Biology, University of Toronto, Scarborough, Toronto, Ontario, Canada M1C1A4
| | - Jia Wang
- Departments of Biological Sciences and Cell and Systems Biology, University of Toronto, Scarborough, Toronto, Ontario, Canada M1C1A4
| | - Greg D Martyn
- Departments of Biological Sciences and Cell and Systems Biology, University of Toronto, Scarborough, Toronto, Ontario, Canada M1C1A4
| | - Farkhunda Rahimy
- Departments of Biological Sciences and Cell and Systems Biology, University of Toronto, Scarborough, Toronto, Ontario, Canada M1C1A4
| | - Greg C Vanlerberghe
- Departments of Biological Sciences and Cell and Systems Biology, University of Toronto, Scarborough, Toronto, Ontario, Canada M1C1A4
| |
Collapse
|