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Vives-Peris V, Gómez-Cadenas A, Pérez-Clemente RM. Proline accumulation and antioxidant response are crucial for citrus tolerance to UV-B light-induced stress. PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:521-531. [PMID: 38568875 DOI: 10.1111/plb.13640] [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: 01/17/2024] [Accepted: 03/03/2024] [Indexed: 04/05/2024]
Abstract
Plants face a wide range of biotic and abiotic stress conditions, which are further intensified by climate change. Among these stressors, increased irradiation in terms of intensity and wavelength range can lead to detrimental effects, such as chlorophyll degradation, destruction of the PSII reaction center, generation of ROS, alterations to plant metabolism, and even plant death. Here, we investigated the responses of two citrus genotypes, Citrus macrophylla (CM), and Troyer citrange (TC) to UV-B light-induced stress, by growing plants of both genotypes under control and UV-B stress conditions for 5 days to evaluate their tolerance mechanisms. TC seedlings had higher sensitivity to UV-B light than CM seedlings, as they showed more damage and increased levels of oxidative harm (indicated by the accumulation of MDA). In contrast, CM seedlings exhibited specific adaptive mechanisms, including accumulation of higher levels of proline under stressful conditions, and enhanced antioxidant capacity, as evidenced by increased ascorbate peroxidase activity and upregulation of the CsAPX2 gene. Phytohormone accumulation patterns were similar in both genotypes, with a decrease in ABA content in response to UV-B light. Furthermore, expression of genes involved in light perception and response was specifically affected in the tolerant CM seedlings, which exhibited higher expression of CsHYH/CsHY5 and CsRUP1-2 genes. These findings underscore the importance of the antioxidant system in citrus plants subjected to UV-B light-induced stress and suggest that CsHYH/CsHY5 and CsRUP1-2 could be considered genes associated with tolerance to such challenging conditions.
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Li C, Du J, Xu H, Feng Z, Chater CCC, Duan Y, Yang Y, Sun X. UVR8-TCP4-LOX2 module regulates UV-B tolerance in Arabidopsis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024; 66:897-908. [PMID: 38506424 DOI: 10.1111/jipb.13648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/18/2024] [Accepted: 03/01/2024] [Indexed: 03/21/2024]
Abstract
The phytohormone jasmonate (JA) coordinates stress and growth responses to increase plant survival in unfavorable environments. Although JA can enhance plant UV-B stress tolerance, the mechanisms underlying the interaction of UV-B and JA in this response remain unknown. In this study, we demonstrate that the UV RESISTANCE LOCUS 8 - TEOSINTE BRANCHED1, Cycloidea and PCF 4 - LIPOXYGENASE2 (UVR8-TCP4-LOX2) module regulates UV-B tolerance dependent on JA signaling pathway in Arabidopsis thaliana. We show that the nucleus-localized UVR8 physically interacts with TCP4 to increase the DNA-binding activity of TCP4 and upregulate the JA biosynthesis gene LOX2. Furthermore, UVR8 activates the expression of LOX2 in a TCP4-dependent manner. Our genetic analysis also provides evidence that TCP4 acts downstream of UVR8 and upstream of LOX2 to mediate plant responses to UV-B stress. Our results illustrate that the UV-B-dependent interaction of UVR8 and TCP4 serves as an important UVR8-TCP4-LOX2 module, which integrates UV-B radiation and JA signaling and represents a new UVR8 signaling mechanism in plants.
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Umryukhin PE, Mikheeva EN, Mishina UM, Proskurnina EV, Malinovskaya EM, Martynov AV, Ershova ES, Veiko NN, Kostyuk SV. Emotional Stress Induces Adaptive Response in Rat Lymphocytes to Subsequent Ionizing Radiation Exposure. Bull Exp Biol Med 2024; 176:548-554. [PMID: 38717568 DOI: 10.1007/s10517-024-06065-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Indexed: 05/18/2024]
Abstract
We studied the molecular mechanisms of cross-adaptation to ionizing radiation (1 Gy) of lymphocytes isolated from rats subjected to emotional stress. The effects of chronic (CES; various types of stress exposure) and acute (AES; forced swimming) emotional stress in rats on indicators of oxidative stress, cell death, and levels of NRF2 and NOX4 proteins involved in the development of the adaptive response were analyzed in isolated lymphocytes. It was found that stress induced an adaptive response in rat lymphocytes and triggered processes similar to the adaptive response induced by low doses of ionizing radiation: an increase in the level of oxidized DNA and cell death, as well as an increase in the content of NOX4 and NRF2 proteins. In animals subjected to emotional stress, suppressed DNA oxidation in response to irradiation, reduced levels of protective factor NRF2, as well as lymphocyte death were observed.
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Thathamangalam Ananthanarayanan A, Raavi V, Srinivas Kondaveeti S, Ramachandran I, Perumal V. Insights on the Radiation-Induced Adaptive Response at the Cellular Level and Its Implications in Cancer Therapy. Cytogenet Genome Res 2023; 163:257-273. [PMID: 37906989 DOI: 10.1159/000534500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 10/05/2023] [Indexed: 11/02/2023] Open
Abstract
BACKGROUND Development of resistance upon exposure to small doses of ionizing radiation followed by higher doses is known as radiation-induced adaptive response (RIAR). Traditionally, the induction of the RIAR phenomenon at the cellular level has been examined in cell lines, animal models, and epidemiological studies where people live in high natural background radiation. SUMMARY The primary intention of the earlier studies was to corroborate the existence of RIAR and the mechanism involved in mediating the response surveyed by exposure to a low dose of radiation (<500 mGy) as priming dose toward the radiation protection point of view. However, the investigation has shifted the focus to understand the relevance of this phenomenon at clinically relevant set-ups (high doses in the order of Gy) and can be exploited during radiotherapy as RIAR is considered a mechanism for the development of radioresistance. Although the knowledge of molecular mechanisms at the cellular level has evolved significantly in multi-fractionated radiotherapy regimes, its relevance in developing radioresistance at low doses remains elusive. The authors recapitulate the existing knowledge on RIAR at cellular levels, specifically after low-dose exposure as an adaptive dose, and discussed its potential implications in clinical radiotherapy outcomes. KEY MESSAGES Recent studies have contributed to understand the signaling molecules, pathways, and inhibitors to mitigate RIAR-mediated radiation resistance and persistent radio-tolerance at the cellular level. Monitoring the disease progression in tumor samples or liquid biopsies before, during, and after therapy with suitable biomarkers has been proposed as a strategy to translate the phenomena into clinical scenario.
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Ramadhani D, Purnami S, Tetriana D, Sugoro I, Suvifan VA, Rahadjeng N, Wanandi SI, Wibowo H, Kashiwakura I, Miura T, Syaifudin M. Chromosome aberrations, micronucleus frequency, and catalase concentration in a population chronically exposed to high levels of radon. Int J Radiat Biol 2022; 99:1188-1203. [PMID: 35930491 DOI: 10.1080/09553002.2022.2110314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 06/14/2022] [Accepted: 07/10/2022] [Indexed: 10/16/2022]
Abstract
PURPOSE To deepen our knowledge on the effects of high levels of indoor radon exposure, we assessed the frequencies of unstable and stable chromosome aberrations and micronucleus (MN), as well as the concentration of an endogenous antioxidant (catalase, CAT), in blood samples of individuals chronically exposed to high indoor radon concentrations in Indonesia (Tande-Tande sub-village, Mamuju, West Sulawesi). Moreover, we also investigated the occurrence of a radio-adaptive response (RAR) in Tande-Tande sub-village inhabitants using the G2 MN assay. MATERIALS AND METHODS The frequencies of dicentric (DC), acentric (AF), ring (R), and translocation (Tr) chromosomes in Tande-Tande inhabitants were compared to those in people living in a reference area with low levels of indoor radon levels (Topoyo village, Indonesia). The number of MN per 1000 binucleated cells (BNC) and CAT concentration per total protein was quantified and compared between groups. Lastly, we irradiated (2 Gy) phytohemagglutinin-stimulated samples in vitro and measured the frequency of MN to verify the occurrence of a RAR in Tande-Tande sub-village inhabitants. RESULTS AND CONCLUSION The frequencies of DC, AF, and Tr did not differ between Tande-Tande inhabitants and control subjects (p = 0.350, 0.521, 0.597). The frequency of MN in Tande-Tande inhabitants was significantly lower than that in the control group (p = 0.006). Similarly, CAT concentration in Tande-Tande inhabitants was also significantly lower than that in the control population (p < 0.001). Significant negative correlations were identified for MN number and CAT concentration versus indoor radon concentration, annual effective dose, or cumulative dose both within groups and when all data were analyzed together. Our findings indicate that, despite the high indoor radon levels, Tande-Tande inhabitants are not under oxidative stress, since this group had lower CAT concentration and MN frequency than those in the control group. The negative correlation between MN frequency and indoor radon concentration, annual effective dose, and cumulative dose suggests the occurrence of an RAR phenomenon in Tande-Tande sub-village inhabitants. This interpretation is also supported by the results of the G2 MN assay, which revealed lower MN frequencies after in vitro irradiation of samples from Tande-Tande sub-village inhabitants than those in samples from the control group (p = 0.0069, for cumulative MN frequency; p = 0.0146, for radiation-induced MN only).
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Hu C, Nawrocki WJ, Croce R. Long-term adaptation of Arabidopsis thaliana to far-red light. PLANT, CELL & ENVIRONMENT 2021; 44:3002-3014. [PMID: 33599977 PMCID: PMC8453498 DOI: 10.1111/pce.14032] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/16/2021] [Accepted: 02/16/2021] [Indexed: 05/04/2023]
Abstract
Vascular plants use carotenoids and chlorophylls a and b to harvest solar energy in the visible region (400-700 nm), but they make little use of the far-red (FR) light. Instead, some cyanobacteria have developed the ability to use FR light by redesigning their photosynthetic apparatus and synthesizing red-shifted chlorophylls. Implementing this strategy in plants is considered promising to increase crop yield. To prepare for this, a characterization of the FR light-induced changes in plants is necessary. Here, we explore the behaviour of Arabidopsis thaliana upon exposure to FR light by following the changes in morphology, physiology and composition of the photosynthetic complexes. We found that after FR-light treatment, the ratio between the photosystems and their antenna size drastically readjust in an attempt to rebalance the energy input to support electron transfer. Despite a large increase in PSBS accumulation, these adjustments result in strong photoinhibition when FR-adapted plants are exposed to light again. Crucially, FR light-induced changes in the photosynthetic membrane are not the result of senescence, but are a response to the excitation imbalance between the photosystems. This indicates that an increase in the FR absorption by the photosystems should be sufficient for boosting photosynthetic activity in FR light.
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Mouginot P, Luviano Aparicio N, Gourcilleau D, Latutrie M, Marin S, Hemptinne JL, Grunau C, Pujol B. Phenotypic Response to Light Versus Shade Associated with DNA Methylation Changes in Snapdragon Plants ( Antirrhinum majus). Genes (Basel) 2021; 12:227. [PMID: 33557416 PMCID: PMC7914928 DOI: 10.3390/genes12020227] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/27/2021] [Accepted: 01/27/2021] [Indexed: 01/17/2023] Open
Abstract
The phenotypic plasticity of plants in response to change in their light environment, and in particularly, to shade is a schoolbook example of ecologically relevant phenotypic plasticity with evolutionary adaptive implications. Epigenetic variation is known to potentially underlie plant phenotypic plasticity. Yet, little is known about its role in ecologically and evolutionary relevant mechanisms shaping the diversity of plant populations in nature. Here we used a reference-free reduced representation bisulfite sequencing method for non-model organisms (epiGBS) to investigate changes in DNA methylation patterns across the genome in snapdragon plants (Antirrhinum majus L.). We exposed plants to sunlight versus artificially induced shade in four highly inbred lines to exclude genetic confounding effects. Our results showed that phenotypic plasticity in response to light versus shade shaped vegetative traits. They also showed that DNA methylation patterns were modified under light versus shade, with a trend towards global effects over the genome but with large effects found on a restricted portion. We also detected the existence of a correlation between phenotypic and epigenetic variation that neither supported nor rejected its potential role in plasticity. While our findings imply epigenetic changes in response to light versus shade environments in snapdragon plants, whether these changes are directly involved in the phenotypic plastic response of plants remains to be investigated. Our approach contributed to this new finding but illustrates the limits in terms of sample size and statistical power of population epigenetic approaches in non-model organisms. Pushing this boundary will be necessary before the relationship between environmentally induced epigenetic changes and phenotypic plasticity is clarified for ecologically relevant mechanisms with evolutionary implications.
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Golubtsov AS, Korostelev NB, Levin BA. Monsters with a shortened vertebral column: A population phenomenon in radiating fish Labeobarbus (Cyprinidae). PLoS One 2021; 16:e0239639. [PMID: 33471803 PMCID: PMC7817016 DOI: 10.1371/journal.pone.0239639] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 12/23/2020] [Indexed: 01/14/2023] Open
Abstract
The phenomenon of a massive vertebral deformity was recorded in the radiating Labeobarbus assemblage from the middle reaches of the Genale River (south-eastern Ethiopia, East Africa). Within this sympatric assemblage, five trophic morphs—generalized, lipped, piscivorous and two scraping feeders—were reported between 1993 and 2019. In 2009, a new morph with prevalence of ~10% was discovered. The new morph, termed ‘short’, had an abnormally shortened vertebral column and a significantly deeper body. This type of deformity is common in farmed Atlantic salmon and other artificially reared fish, but is rare in nature. In the Genale Labeobarbus assemblage, the deformity was present exclusively within the generalized and lipped morphs. The short morph had between seven and 36 deformed (compressed and/or fused) vertebrae. Their body depth was positively correlated with number of deformed vertebrae. In another collection in 2019, the short morph was still present at a frequency of 11%. Various environmental and genetic factors could contribute to the development of this deformity in the Genale Labeobarbus, but based on the available data, it is impossible to confidently identify the key factor(s). Whether the result of genetics, the environment, or both, this deep-bodied phenotype is assumed to be an anti-predator adaptation, as there is evidence of its selective advantage in the generalized morph. The Genale monstrosity is the first reported case of a massive deformity of the vertebral column in a natural population of African fishes.
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Singh B, Patwardhan RS, Jayakumar S, Sharma D, Sandur SK. Oxidative stress associated metabolic adaptations regulate radioresistance in human lung cancer cells. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2020; 213:112080. [PMID: 33232882 DOI: 10.1016/j.jphotobiol.2020.112080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 10/05/2020] [Accepted: 11/07/2020] [Indexed: 01/29/2023]
Abstract
Differential inherent and acquired radioresistance of human lung cancer cells contribute to poor therapeutic outcome and tumor recurrence after radiotherapy. Inherent radioresistance of lung cancer cells is known to be associated with ROSLow cancer stem cells (CSCs). However, mechanism of acquired radioresistance in lung cancer cells is poorly understood. Here, we exposed human lung cancer cells (A549) to a cumulative dose of 40Gy and allowed the radioresistant (RR) survivors to divide and form macroscopic colonies after each fraction of 5Gy dose. The RR subline exhibited enrichment of cytosolic ROSHigh cells without specific increase in mitochondrial ROS levels. We found a concomitant increase in the expression of redox regulatory transcription factor Nrf2 and its dependent antioxidant genes in RR cells and cell cycle delay as compared to parental cells. The treatment of RR cells with Nrf2 inhibitor resulted in decreased clonogenic survival indicating their addiction to Nrf2 for metabolic adaptations under high levels of cytosolic ROS. A causal role of inherent ROS levels in conferring radioresistance was established by sorting ROSHigh and ROSLow populations from parental and RR cells. It was observed that ROSHigh population from both parental and RR cells exhibited radioresistance as observed by clonogenic assay. Interestingly, ROSHigh population of cells exhibited higher levels of cellular thiols in both parental and RR cells. Thus, our observations highlight presence of a novel subpopulation in lung cancer cells, which exhibits radioresistance by maintaining 'oxidative stress' and Nrf2 dependent metabolic adaptations. We also posit Nrf2 pathway as a druggable target for radiosensitization of RR A549 cells.
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Chen J, Okimura K, Yoshimura T. Light and Hormones in Seasonal Regulation of Reproduction and Mood. Endocrinology 2020; 161:5879749. [PMID: 32738138 PMCID: PMC7442225 DOI: 10.1210/endocr/bqaa130] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 07/27/2020] [Indexed: 12/26/2022]
Abstract
Organisms that inhabit the temperate zone exhibit various seasonal adaptive behaviors, including reproduction, hibernation, molting, and migration. Day length, known as photoperiod, is the most noise-free and widely used environmental cue that enables animals to anticipate the oncoming seasons and adapt their physiologies accordingly. Although less clear, some human traits also exhibit seasonality, such as birthrate, mood, cognitive brain responses, and various diseases. However, the molecular basis for human seasonality is poorly understood. Herein, we first review the underlying mechanisms of seasonal adaptive strategies of animals, including seasonal reproduction and stress responses during the breeding season. We then briefly summarize our recent discovery of signaling pathways involved in the winter depression-like phenotype in medaka fish. We believe that exploring the regulation of seasonal traits in animal models will provide insight into human seasonality and aid in the understanding of human diseases such as seasonal affective disorder (SAD).
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Jiang J, Xiao Y, Chen H, Hu W, Zeng L, Ke H, Ditengou FA, Devisetty U, Palme K, Maloof J, Dehesh K. Retrograde Induction of phyB Orchestrates Ethylene-Auxin Hierarchy to Regulate Growth. PLANT PHYSIOLOGY 2020; 183:1268-1280. [PMID: 32430463 PMCID: PMC7333703 DOI: 10.1104/pp.20.00090] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 05/11/2020] [Indexed: 05/19/2023]
Abstract
Exquisitely regulated plastid-to-nucleus communication by retrograde signaling pathways is essential for fine-tuning of responses to the prevailing environmental conditions. The plastidial retrograde signaling metabolite methylerythritol cyclodiphosphate (MEcPP) has emerged as a stress signal transduced into a diverse ensemble of response outputs. Here, we demonstrate enhanced phytochrome B protein abundance in red light-grown MEcPP-accumulating ceh1 mutant Arabidopsis (Arabidopsis thaliana) plants relative to wild-type seedlings. We further establish MEcPP-mediated coordination of phytochrome B with auxin and ethylene signaling pathways and uncover differential hypocotyl growth of red light-grown seedlings in response to these phytohormones. Genetic and pharmacological interference with ethylene and auxin pathways outlines the hierarchy of responses, placing ethylene epistatic to the auxin signaling pathway. Collectively, our findings establish a key role of a plastidial retrograde metabolite in orchestrating the transduction of a repertoire of signaling cascades. This work positions plastids at the zenith of relaying information coordinating external signals and internal regulatory circuitry to secure organismal integrity.
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Shi H, He X, Zhao Y, Lu S, Guo Z. Constitutive expression of a group 3 LEA protein from Medicago falcata (MfLEA3) increases cold and drought tolerance in transgenic tobacco. PLANT CELL REPORTS 2020; 39:851-860. [PMID: 32240329 DOI: 10.1007/s00299-020-02534-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 03/18/2020] [Indexed: 05/22/2023]
Abstract
KEY MESSAGE MfLEA3 is involved in protection of catalase activity and confers multiple abiotic stress tolerance. Late embryogenesis abundant (LEA) proteins are involved in plant growth, development and abiotic stress tolerance. A member of group 3 LEA proteins from Medicago sativa subsp. falcata (L.) Arcang, MfLEA3, was investigated in the study. MfLEA3 transcript was induced in response to cold, dehydration, and abscisic acid (ABA), while the cold-induced transcript of MfLEA3 was blocked by pretreatment with inhibitor of ABA synthesis. Constitutive expression of MfLEA3 led to enhanced tolerance to cold, drought, and high-light stress in transgenic tobacco plants. Compared to accumulated reactive oxygen species (ROS) in the wild-type in response to treatments with low temperature, drought, and high light, ROS were not accumulated in transgenic plants. Superoxide dismutase, catalase (CAT), and ascorbate-peroxidase activities were increased in all plants after treatments with the above stresses, while higher CAT activity was maintained in transgenic plants compared with wild-type. However, transcript level of CAT-encoding genes including CAT1, CAT2, and CAT3 showed no significant difference between transgenic plants and wild-type, indicating that the higher CAT activity was not associated with its gene expression. ABA sensitivity and transcripts of several ABA and stress-responsive genes showed no difference between transgenic plant and wild-type, indicating that ABA signaling was not affected by constitutive expression of MfLEA3. The results suggest that MfLEA3 may be involved in the protection of CAT activity and confers multiple abiotic stress tolerance.
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Lu X, Zhou Y, Fan F, Peng J, Zhang J. Coordination of light, circadian clock with temperature: The potential mechanisms regulating chilling tolerance in rice. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2020; 62:737-760. [PMID: 31243851 DOI: 10.1111/jipb.12852] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 06/19/2019] [Indexed: 06/09/2023]
Abstract
Rice (Oryza sativa L.) is a major staple food crop for over half of the world's population. As a crop species originated from the subtropics, rice production is hampered by chilling stress. The genetic mechanisms of rice responses to chilling stress have attracted much attention, focusing on chilling-related gene mining and functional analyses. Plants have evolved sophisticated regulatory systems to respond to chilling stress in coordination with light signaling pathway and internal circadian clock. However, in rice, information about light-signaling pathways and circadian clock regulation and their roles in chilling tolerance remains elusive. Further investigation into the regulatory network of chilling tolerance in rice is needed, as knowledge of the interaction between temperature, light, and circadian clock dynamics is limited. Here, based on phenotypic analysis of transgenic and mutant rice lines, we delineate the relevant genes with important regulatory roles in chilling tolerance. In addition, we discuss the potential coordination mechanism among temperature, light, and circadian clock in regulating chilling response and tolerance of rice, and provide perspectives for the ongoing chilling signaling network research in rice.
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Griffing AH, Gamble T, Bauer AM. Distinct patterns of pigment development underlie convergent hyperpigmentation between nocturnal and diurnal geckos (Squamata: Gekkota). BMC Evol Biol 2020; 20:40. [PMID: 32220231 PMCID: PMC7099784 DOI: 10.1186/s12862-020-01604-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 03/18/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Evolutionary transitions in temporal niche necessitates specialized morphology, physiology, and behaviors. Diurnal, heliothermic squamates (lizards and snakes) that bask require protection from ultraviolet radiation (UV) that can damage internal organs such as the brain, viscera, and gonads. Many smaller squamates have accomplished this protection by hyperpigmentation of the peritoneum and subcutaneous dorsum. Typically, nocturnal species do not require these protections from ultraviolet light. However, some nocturnal species that exhibit extreme crypsis may be exposed to sunlight and UV and require some means of mediating that damage. One such species is Gekko (Ptychozoon) kuhli, a nocturnal, arboreal gecko that uses extreme crypsis to blend in with tree bark. Hiding motionless on tree trunks leaves geckos exposed to sunlight during the day. Thus, we predict that G. kuhli will have independently evolved a hyperpigmented phenotype. To investigate this hypothesized association between temporal niche, behavior, and morphology, we characterized adult subcutaneous pigment for eight gecko species and embryonic pigment accumulation for a subset of four of these species, exhibiting diverse temporal niche and thermoregulatory behaviors. We predicted that nocturnal/potentially-heliothermic G. kuhli would exhibit hyperpigmentation of internal structures like that of diurnal/heliothermic geckos. We further predicted that embryonic pigment accumulation of G. kuhli would resemble that of diurnal/heliothermic as opposed to nocturnal/thigmothermic geckos. RESULTS We found that temporal niche and thermoregulatory behavior predicted the degree of subcutaneous pigment in the eight gecko species examined. We demonstrate that G. kuhli accumulates pigment extremely early in embryonic development, unlike a diurnal/heliothermic gecko species, despite having a similar adult phenotype. CONCLUSIONS The evolution of hyperpigmentation in G. kuhli is likely an adaptation to limit damage from occasional daytime UV exposure caused by crypsis-associated basking behavior. Gekko kuhli achieves its hyperpigmented phenotype through a derived developmental pattern, not seen in any other lizard species investigated to date, suggesting novel temporal differences in the migration and/or differentiation of reptilian neural crest derivatives.
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Berkowitz BA, Olds HK, Richards C, Joy J, Rosales T, Podolsky RH, Childers KL, Hubbard WB, Sullivan PG, Gao S, Li Y, Qian H, Roberts R. Novel imaging biomarkers for mapping the impact of mild mitochondrial uncoupling in the outer retina in vivo. PLoS One 2020; 15:e0226840. [PMID: 31923239 PMCID: PMC6953833 DOI: 10.1371/journal.pone.0226840] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 12/05/2019] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To test the hypothesis that imaging biomarkers are useful for evaluating in vivo rod photoreceptor cell responses to a mitochondrial protonophore. METHODS Intraperitoneal injections of either the mitochondrial uncoupler 2,4 dinitrophenol (DNP) or saline were given to mice with either higher [129S6/eVTac (S6)] or lower [C57BL/6J (B6)] mitochondrial reserve capacities and were studied in dark or light. We measured: (i) the external limiting membrane-retinal pigment epithelium region thickness (ELM-RPE; OCT), which decreases substantially with upregulation of a pH-sensitive water removal co-transporter on the apical portion of the RPE, and (ii) the outer retina R1 (= 1/(spin lattice relaxation time (T1), an MRI parameter proportional to oxygen / free radical content. RESULTS In darkness, baseline rod energy production and consumption are relatively high compared to that in light, and additional metabolic stimulation with DNP provoked thinning of the ELM-RPE region compared to saline injection in S6 mice; ELM-RPE thickness was unresponsive to DNP in B6 mice. Also, dark-adapted S6 mice given DNP showed a decrease in outer retina R1 values compared to saline injection in the inferior retina. In dark-adapted B6 mice, transretinal R1 values were unresponsive to DNP in superior and inferior regions. In light, with its relatively lower basal rod energy production and consumption, DNP caused ELM-RPE thinning in both S6 and B6 mice. CONCLUSIONS The present results raise the possibility of non-invasively evaluating the mouse rod mitochondrial energy ecosystem using new DNP-assisted OCT and MRI in vivo assays.
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Ganguly S, Saha S, Vangaru S, Purkayastha S, Das D, Saha AK, Roy A, Das S, Bhattacharyya PK, Mukherjee S, Bhattacharyya S. Identification and analysis of low light tolerant rice genotypes in field conditions and their SSR-based diversity in various abiotic stress tolerant lines. J Genet 2020; 99:24. [PMID: 33361642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The yield potentiality of kharif rice is not completely used even under well-irrigated agro-ecosystem, mainly due to low irradiance by overcast cloud throughout the growing season in eastern India. We observed more than 50% yield reduction compared to the performance of 100 high-yield genotypes for consecutive three years both under open and 30-35% reduced light intensity, mainly by 34%, 25% and 12% reduction of panicle number, grains per panicle and test weight. As per the analysis of variance, genotypic variance explained 39% of the total yield-variation under shade with 58% heritability. Overall, the maintenance of equal panicle per plant in both open and shade has the highest association with shade tolerance. Purnendu, Sashi and Pantdhan19 showed less than 28% yield-reduction by maintenance or even by increasing grain numbers under shade and test weight. On the other hand, maintenance of an equal number of panicle under both situations was the key to the tolerance of Bhasamanik, Sasarang, Rudra and Swarnaprabha. As compared to open, we noticed the improvement of chlorophyll a and b under shade but saw a poor correlation with the shade tolerance index. Comparing the net photosynthesis rate (Pn) in eight genotypes, we found the best tolerant line ranked last with least Pn at low light intensity (400 μmol m-2 s-1). We also identified diverse parental combinations between newly identified shade tolerant and abiotic stress tolerant high-yielding rice lines following diversity analysis using 54 simple-sequence repeats. Thus, the selected tolerant lines from a large set of genotypes with different adjustment ability to keep up high yield under low light intensity can be used for physiological, molecular analysis as well as pyramiding of traits.
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Díaz-Riaño J, Posada L, Acosta IC, Ruíz-Pérez C, García-Castillo C, Reyes A, Zambrano MM. Computational search for UV radiation resistance strategies in Deinococcus swuensis isolated from Paramo ecosystems. PLoS One 2019; 14:e0221540. [PMID: 31790419 PMCID: PMC6886795 DOI: 10.1371/journal.pone.0221540] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/15/2019] [Indexed: 02/07/2023] Open
Abstract
Ultraviolet radiation (UVR) is widely known as deleterious for many organisms since it can cause damage to biomolecules either directly or indirectly via the formation of reactive oxygen species. The goal of this study was to analyze the capacity of high-mountain Espeletia hartwegiana plant phyllosphere microorganisms to survive UVR and to identify genes related to resistance strategies. A strain of Deinococcus swuensis showed a high survival rate of up to 60% after UVR treatment at 800J/m2 and was used for differential expression analysis using RNA-seq after exposing cells to 400J/m2 of UVR (with >95% survival rate). Differentially expressed genes were identified using the R-Bioconductor package NOISeq and compared with other reported resistance strategies reported for this genus. Genes identified as being overexpressed included transcriptional regulators and genes involved in protection against damage by UVR. Non-coding (nc)RNAs were also differentially expressed, some of which have not been previously implicated. This study characterized the immediate radiation response of D. swuensis and indicates the involvement of ncRNAs in the adaptation to extreme environmental conditions.
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Singharoy A, Maffeo C, Delgado-Magnero KH, Swainsbury DJK, Sener M, Kleinekathöfer U, Vant JW, Nguyen J, Hitchcock A, Isralewitz B, Teo I, Chandler DE, Stone JE, Phillips JC, Pogorelov TV, Mallus MI, Chipot C, Luthey-Schulten Z, Tieleman DP, Hunter CN, Tajkhorshid E, Aksimentiev A, Schulten K. Atoms to Phenotypes: Molecular Design Principles of Cellular Energy Metabolism. Cell 2019; 179:1098-1111.e23. [PMID: 31730852 PMCID: PMC7075482 DOI: 10.1016/j.cell.2019.10.021] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/04/2019] [Accepted: 10/21/2019] [Indexed: 01/01/2023]
Abstract
We report a 100-million atom-scale model of an entire cell organelle, a photosynthetic chromatophore vesicle from a purple bacterium, that reveals the cascade of energy conversion steps culminating in the generation of ATP from sunlight. Molecular dynamics simulations of this vesicle elucidate how the integral membrane complexes influence local curvature to tune photoexcitation of pigments. Brownian dynamics of small molecules within the chromatophore probe the mechanisms of directional charge transport under various pH and salinity conditions. Reproducing phenotypic properties from atomistic details, a kinetic model evinces that low-light adaptations of the bacterium emerge as a spontaneous outcome of optimizing the balance between the chromatophore's structural integrity and robust energy conversion. Parallels are drawn with the more universal mitochondrial bioenergetic machinery, from whence molecular-scale insights into the mechanism of cellular aging are inferred. Together, our integrative method and spectroscopic experiments pave the way to first-principles modeling of whole living cells.
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Bdolach E, Prusty MR, Faigenboim-Doron A, Filichkin T, Helgerson L, Schmid KJ, Greiner S, Fridman E. Thermal plasticity of the circadian clock is under nuclear and cytoplasmic control in wild barley. PLANT, CELL & ENVIRONMENT 2019; 42:3105-3120. [PMID: 31272129 DOI: 10.1111/pce.13606] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 06/27/2019] [Accepted: 06/30/2019] [Indexed: 06/09/2023]
Abstract
Temperature compensation, expressed as the ability to maintain clock characteristics (mainly period) in face of temperature changes, that is, robustness, is considered a key feature of circadian clock systems. In this study, we explore the genetic basis for lack of robustness, that is, plasticity, of circadian clock as reflected by photosynthesis rhythmicity. The clock rhythmicity of a new wild barley reciprocal doubled haploid population was analysed with a high temporal resolution of pulsed amplitude modulation of chlorophyll fluorescence under optimal (22°C) and high (32°C) temperature. This comparison between two environments pointed to the prevalence of clock acceleration under heat. Genotyping by sequencing of doubled haploid lines indicated a rich recombination landscape with minor fixation (less than 8%) for one of the parental alleles. Quantitative genetic analysis included genotype by environment interactions and binary-threshold models. Variation in the circadian rhythm plasticity phenotypes, expressed as change (delta) of period and amplitude under two temperatures, was associated with maternal organelle genome (the plasmotype), as well as with several nuclear loci. This first reported rhythmicity driven by nuclear loci and plasmotype with few identified variants, paves the way for studying impact of cytonuclear variations on clock robustness and on plant adaptation to changing environments.
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Zulfugarov IS, Wu G, Tovuu A, Lee CH. Effect of oxygen on the non-photochemical quenching of vascular plants and potential oxygen deficiency in the stroma of PsbS-knock-out rice. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 286:1-6. [PMID: 31300135 DOI: 10.1016/j.plantsci.2019.05.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/25/2019] [Accepted: 05/18/2019] [Indexed: 06/10/2023]
Abstract
The excessive and harmful light energy absorbed by the photosystem (PS) II of higher plants is dissipated as heat through a protective mechanism termed non-photochemical quenching (NPQ) of chlorophyll fluorescence. PsbS-knock-out (KO) mutants lack the trans-thylakoid proton gradient (ΔpH)-dependent part of NPQ. To elucidate the molecular mechanism of NPQ, we investigated its dependency on oxygen. The development of NPQ in wild-type (WT) rice under low-oxygen (LO) conditions was reduced to more than 50% of its original value. However, under high-oxygen (HO) conditions, the NPQ of both WT and PsbS-KO mutants recovered. Moreover, WT and PsbS-KO mutant leaves infiltrated with the ΔpH dissipating uncoupler nigericin showed increased NPQ values under HO conditions. The experiments using intact chloroplasts and protoplasts of Arabidopsis thaliana supported that the LO effects observed in rice leaves were not due to carbon dioxide deficiency. There was a noticeable 90% reduction in the half-time of P700 oxidation rate in LO-treated leaves compared with that of WT control leaves, but the HO treatment did not significantly change the half-time of P700 oxidation rate. Overall, the results obtained here indicate that the stroma of the PsbS-KO plants could be potentially under O2 deficiency. Because the functions of PsbS in rice leaves are likely to be similar to those in other higher plants, our findings offer novel insights into the role of oxygen in the development of NPQ.
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Slot M, Krause GH, Krause B, Hernández GG, Winter K. Photosynthetic heat tolerance of shade and sun leaves of three tropical tree species. PHOTOSYNTHESIS RESEARCH 2019; 141:119-130. [PMID: 30054784 DOI: 10.1007/s11120-018-0563-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 07/21/2018] [Indexed: 06/08/2023]
Abstract
Previous studies of heat tolerance of tropical trees have focused on canopy leaves exposed to full sunlight and high temperatures. However, in lowland tropical forests with leaf area indices of 5-6, the vast majority of leaves experience varying degrees of shade and a reduced heat load compared to sun leaves. Here we tested whether heat tolerance is lower in shade than in sun leaves. For three tropical tree species, Calophyllum inophyllum, Inga spectabilis, and Ormosia macrocalyx, disks of fully developed shade and sun leaves were subjected to 15-min heat treatments, followed by measurement of chlorophyll a fluorescence after 48 h of recovery. In two of the three species, the temperature causing a 50% decrease of the fluorescence ratio Fv/Fm (T50) was significantly lower (by ~ 1.0 °C) in shade than in sun leaves, indicating a moderately decreased heat tolerance of shade leaves. In shade leaves of these two species, the rise in initial fluorescence, F0, also occurred at lower temperatures. In the third species, there was no shade-sun difference in T50. In situ measurements of photosynthetic CO2 assimilation showed that the optimum temperature for photosynthesis tended to be lower in shade leaves, although differences were not significant. At supra-optimal temperatures, photosynthesis was largely constrained by stomatal conductance, and the high-temperature CO2 compensation point, TMax, occurred at considerably lower temperatures than T50. Our study demonstrates that the temperature response of shade leaves of tropical trees differs only marginally from that of sun leaves, both in terms of heat tolerance and photosynthetic performance.
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He P, Wright IJ, Zhu S, Onoda Y, Liu H, Li R, Liu X, Hua L, Oyanoghafo OO, Ye Q. Leaf mechanical strength and photosynthetic capacity vary independently across 57 subtropical forest species with contrasting light requirements. THE NEW PHYTOLOGIST 2019; 223:607-618. [PMID: 30887533 DOI: 10.1111/nph.15803] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 03/12/2019] [Indexed: 06/09/2023]
Abstract
Leaf mechanical strength and photosynthetic capacity are critical plant life-history traits associated with tolerance and growth under various biotic and abiotic stresses. In principle, higher mechanical resistance achieved via higher relative allocation to cell walls should slow photosynthetic rates. However, interspecific relationships among these two leaf functions have not been reported. We measured leaf traits of 57 dominant woody species in a subtropical evergreen forest in China, focusing especially on photosynthetic rates, mechanical properties, and leaf lifespan (LLS). These species were assigned to two ecological strategy groups: shade-tolerant species and light-demanding species. On average, shade-tolerant species had longer LLS, higher leaf mechanical strength but lower photosynthetic rates, and exhibited longer LLS for a given leaf mass per area (LMA) or mechanical strength than light-demanding species. Depending on the traits and the basis of expression (per area or per mass), leaf mechanical resistance and photosynthetic capacity were either deemed unrelated, or only weakly negatively correlated. We found only weak support for the proposed trade-off between leaf biomechanics and photosynthesis among co-occurring woody species. This suggests there is considerable flexibility in these properties, and the observed relationships may result more so from trait coordination than any physically or physiologically enforced trade-off.
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Gorman MR, Elliott JA. Exceptional Entrainment of Circadian Activity Rhythms With Manipulations of Rhythm Waveform in Male Syrian Hamsters. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:187-199. [PMID: 31249479 PMCID: PMC6585525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The activity/rest rhythm of mammals reflects the output of an endogenous circadian oscillator entrained to the solar day by light. Despite detailed understanding of the neural and molecular bases of mammalian rhythms, we still lack practical tools for achieving rapid and flexible adjustment of clocks to accommodate shift-work, trans-meridian jet travel, or space exploration. Efforts to adapt clocks have focused on resetting the phase of an otherwise unaltered circadian clock. Departing from this tradition, recent work has demonstrated that bifurcation of circadian waveform in mice facilitates entrainment to extremely long and short zeitgeber periods. Here we evaluate the formal nature of entrainment to extreme non-24 h days in male Syrian hamsters. Wheel-running rhythms were first bifurcated into a 24 h rest/activity/rest/activity cycle according to established methods. Thereafter the 24 h lighting cycle was incrementally adjusted over several weeks to 30 h or to 18 h. Almost without exception, wheel-running rhythms of hamsters in gradually lengthened or shortened zeitgebers remained synchronized with the lighting cycle, with greater temporal precision observed in the former condition. Data from animals transferred abruptly from 24 h days to long or short cycles suggested that gradual adaptation facilitates but is not necessary for successful behavioral entrainment. The unprecedented behavioral adaptation following waveform bifurcation reveals a latent plasticity in mammalian circadian systems that can be realized in the absence of pharmacological or genetic manipulations. Oscillator interactions underlying circadian waveform manipulation, thus, represent a tractable target for understanding and enhancing circadian rhythm resetting.
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Klimenko O, Pernis M, Danchenko M, Skultéty L, Klubicová K, Shevchenko G. Natural ecotype of Arabidopsis thaliana (L.) Heynh (Chernobyl-07) respond to cadmium stress more intensively than the sensitive ecotypes Oasis and Columbia. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 173:86-95. [PMID: 30769207 DOI: 10.1016/j.ecoenv.2019.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 02/01/2019] [Accepted: 02/03/2019] [Indexed: 05/19/2023]
Abstract
Large areas polluted with toxic heavy metals or radionuclides were formed as a side product of rapid industrial development of human society. Plants, due to their sessile nature, should adapt to these challenging genotoxic environmental conditions and develop resistance. Herein, we evaluated the response of three natural ecotypes of Arabidopsis thaliana (L.) Heynh (Oasis, Columbia-0, and Chernobyl-07) to cadmium, using discovery gel-based proteomics. These accessions are differing by level of tolerance to heavy metal probably achieved by various exposure to chronic ionizing radiation. Based on the pairwise comparison (control versus cadmium-treated) we recognized 5.8-13.4% of identified proteins as significantly altered at the presence of cadmium. Although the majority of photosynthesis-related proteins were found to be less abundant in all ecotypes it was noted that in contrast to the sensitive variants (Col and Oas), the tolerant Che accession may activate the mechanism preserving photosynthesis and energy production. Also, proteins modulating energy budget through alternative route and mediating higher resistance to heavy metals were upregulated in this ecotype. Although we suggest that regulation of enzymes acting in peptide and protein synthesis, protection of the plants against various abiotic stresses, or those neutralizing the effects of reactive oxygen species are rather associated with general response to cadmium, they were found to be altered more intensively in the Che accession. Thus, the identified affected proteins may represent good candidate molecules for molecular breeding to improve tolerance of crops to heavy metal stress.
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Deans RM, Brodribb TJ, Busch FA, Farquhar GD. Plant water-use strategy mediates stomatal effects on the light induction of photosynthesis. THE NEW PHYTOLOGIST 2019; 222:382-395. [PMID: 30372523 DOI: 10.1111/nph.15572] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 10/22/2018] [Indexed: 05/07/2023]
Abstract
More efficient gas exchange strategies under dynamic light environments have been hypothesised to contribute to the dominance of angiosperms in the vascular plant flora. However, we still lack a clear understanding of how stomatal dynamics affect photosynthetic dynamics and whether differences exist between lineages. Stomatal and photosynthetic dynamics following changes in irradiance were studied in 15 species, encompassing ferns, gymnosperms and angiosperms. We determined the effect of stomatal speed on dynamic photosynthesis and water loss. Moreover, we assessed whether dynamic behaviour followed evolutionary lineage divisions, or whether ecological adaptation to maximise light fleck use could describe dynamic behaviour. We found that species with fast stomatal opening, such as ferns, forgo less photosynthesis during photosynthetic induction. By contrast, there was no relationship between stomatal closure speed and the water wasted by transiently more-open stomata, because species with higher rates of gas exchange also showed faster stomatal closure. Shade-adapted species possessed fast-opening but slow-closing stomata, consistent with ecological adaptation to maximise light fleck use. Our results suggest dynamic behaviour follows adaptive ecological trends more strongly than evolutionary ones, but angiosperms may benefit from relatively faster photosynthetic induction by adopting a less conservative water-use strategy.
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