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Pradhan B, Baral S, Patra S, Behera C, Nayak R, MubarakAli D, Jena M. Delineation of gamma irradiation (60Co) induced oxidative stress by decrypting antioxidants and biochemical responses of microalga, Chlorella sp. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101595] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Todorova T, Miteva D, Chankova S. DNA susceptibility of Saccharomyces cerevisiae to Zeocin depends on the growth phase. Int Microbiol 2019; 22:419-428. [PMID: 30875034 DOI: 10.1007/s10123-019-00065-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 01/03/2019] [Accepted: 02/13/2019] [Indexed: 11/26/2022]
Abstract
The aim of this study was to evaluate the level of Zeocin-induced double-strand breaks (DSBs) in Saccharomyces cerevisiae cells in a different growth phase, using constant-field gel electrophoresis (CFGE). Saccharomyces cerevisiae diploid strain D7ts1 with enhanced cellular permeability was used. The effects of growth phase and treatment time were evaluated based on Zeocin-induced DSBs, measured by CFGE. Survival assay was also applied. No protoplast isolation was necessary for the detection of DSBs in strain D7ts1. Differences in the response of cells depending on the growth phase were obtained. Cells in exponential growth phase had increased DSB levels only after Zeocin treatment with concentrations equal or higher than 200 μgml-1. Increasing treatment time did not result in higher DSB levels. Oppositely, treatment of cells at the beginning of stationary phase with Zeocin concentrations resulted in more than 1.5-fold increase in DSB levels in comparison with those in untreated cells. Increased DSB levels were measured for all the treatment times. A dose-dependent decrease in cell survival was observed after Zeocin treatment with concentrations in the range of lethality LD20-LD50. A strong negative correlation was calculated between the levels of DSBs and cell survival. New information is provided concerning DNA susceptibility depending on the growth phase. DNA susceptibility is higher in cells at the beginning of stationary phase than those in exponential phase. Data presented here illustrate that the optimized by us CFGE protocol is sensitive and could be used successfully for DSB measurement in Saccharomyces cerevisiae strains with enhanced cellular permeability.
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Affiliation(s)
- Teodora Todorova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin str., 1113, Sofia, Bulgaria
| | - Daniela Miteva
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin str., 1113, Sofia, Bulgaria
| | - Stephka Chankova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin str., 1113, Sofia, Bulgaria.
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Ji K, Wang Y, Du L, Xu C, Liu Y, He N, Wang J, Liu Q. Research Progress on the Biological Effects of Low-Dose Radiation in China. Dose Response 2019; 17:1559325819833488. [PMID: 30833876 PMCID: PMC6393828 DOI: 10.1177/1559325819833488] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/19/2018] [Accepted: 12/29/2018] [Indexed: 01/07/2023] Open
Abstract
Human are exposed to ionizing radiation from natural and artificial sources, which consequently poses a possible risk to human health. However, accumulating evidence indicates that the biological effects of low-dose radiation (LDR) are different from those of high-dose radiation (HDR). Low-dose radiation–induced hormesis has been extensively observed in different biological systems, including immunological and hematopoietic systems. Adaptive responses in response to LDR that can induce cellular resistance to genotoxic effects from subsequent exposure to HDR have also been described and researched. Bystander effects, another type of biological effect induced by LDR, have been shown to widely occur in many cell types. Furthermore, the influence of LDR-induced biological effects on certain diseases, such as cancer and diabetes, has also attracted the interest of researchers. Many studies have suggested that LDR has the potential antitumor and antidiabetic complications effects. In addition, the researches on whether LDR could induce stochastic effects were also debated. Studies on the biological effects of LDR in China started in 1970s and considerable progress has been made since. In the present article, we provide an overview of the research progress on the biological effects of LDR in China.
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Affiliation(s)
- Kaihua Ji
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Yan Wang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Liqing Du
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Chang Xu
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Yang Liu
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Ningning He
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Jinhan Wang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
| | - Qiang Liu
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Department of Radiobiology, Institute of Radiation Medicine of Chinese Academy of Medical Science & Pecking Union Medical College, Tianjin, PR China
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Gomes T, Xie L, Brede D, Lind OC, Solhaug KA, Salbu B, Tollefsen KE. Sensitivity of the green algae Chlamydomonas reinhardtii to gamma radiation: Photosynthetic performance and ROS formation. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2017; 183:1-10. [PMID: 27978482 DOI: 10.1016/j.aquatox.2016.12.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 10/19/2016] [Accepted: 12/02/2016] [Indexed: 06/06/2023]
Abstract
The aquatic environment is continuously exposed to ionizing radiation from both natural and anthropogenic sources, making the characterization of ecological and health risks associated with radiation of large importance. Microalgae represent the main source of biomass production in the aquatic ecosystem, thus becoming a highly relevant biological model to assess the impacts of gamma radiation. However, little information is available on the effects of gamma radiation on microalgal species, making environmental radioprotection of this group of species challenging. In this context, the present study aimed to improve the understanding of the effects and toxic mechanisms of gamma radiation in the unicellular green algae Chlamydomonas reinhardtii focusing on the activity of the photosynthetic apparatus and ROS formation. Algal cells were exposed to gamma radiation (0.49-1677mGy/h) for 6h and chlorophyll fluorescence parameters obtained by PAM fluorometry, while two fluorescent probes carboxy-H2DFFDA and DHR 123 were used for the quantification of ROS. The alterations seen in functional parameters of C. reinhardtii PSII after 6h of exposure to gamma radiation showed modifications of PSII energy transfer associated with electron transport and energy dissipation pathways, especially at the higher dose rates used. Results also showed that gamma radiation induced ROS in a dose-dependent manner under both light and dark conditions. The observed decrease in photosynthetic efficiency seems to be connected to the formation of ROS and can potentially lead to oxidative stress and cellular damage in chloroplasts. To our knowledge, this is the first report on changes in several chlorophyll fluorescence parameters associated with photosynthetic performance and ROS formation in microalgae after exposure to gamma radiation.
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Affiliation(s)
- Tânia Gomes
- Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349, Oslo, Norway; Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway.
| | - Li Xie
- Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349, Oslo, Norway; Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway
| | - Dag Brede
- Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway; Department for Environmental Sciences, Faculty of Environmental Science & Technology, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432, Ås, Norway
| | - Ole-Christian Lind
- Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway; Department for Environmental Sciences, Faculty of Environmental Science & Technology, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432, Ås, Norway
| | - Knut Asbjørn Solhaug
- Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway; Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences (NMBU), Postbox 5003, N-1432, Ås, Norway
| | - Brit Salbu
- Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway; Department for Environmental Sciences, Faculty of Environmental Science & Technology, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432, Ås, Norway
| | - Knut Erik Tollefsen
- Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349, Oslo, Norway; Centre for Environmental Radioactivity, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432 Ås, Norway; Department for Environmental Sciences, Faculty of Environmental Science & Technology, Norwegian University of Life Sciences (NMBU), Post Box 5003, N-1432, Ås, Norway
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Chankova SG, Dimova EG, Mitrovska Z, Miteva D, Mokerova DV, Yonova PA, Yurina NP. Antioxidant and HSP70B responses in Chlamydomonas reinhardtii genotypes with different resistance to oxidative stress. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 101:131-137. [PMID: 24507138 DOI: 10.1016/j.ecoenv.2013.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 11/13/2013] [Accepted: 11/18/2013] [Indexed: 06/03/2023]
Abstract
Today, the information from model species that differ in their resistance to oxidative stress and the determination of suitable plant markers for screening stress-resistant genotypes are essential for better understanding of plant stress responses and for selection. Here we aimed to assess the differences in antioxidant and HSP70B responses to paraquat treatment between genotypes susceptible and resistant to oxidative stress. Four genotypes of Chlamydomonas reinhardtii were chosen as a model of plant cells: two susceptible genotypes: wild type and paraquat-sensitive; and two paraquat-resistant genotypes: with high and moderate resistance. Varying responses to paraquat treatment were found depending on the genotype and paraquat concentrations. High paraquat concentrations (>50μM) were shown to be very stressful for all C. reinhardtii genotypes, leading to inhibition of enzyme activity. Only the paraquat-sensitive genotype responded to low-level paraquat treatment with a marked enhancement of SOD, CAT, GST activities. The lack of statistically significant response measured as SOD, CAT, GST activities in WT and resistant genotypes could be considered as an indication of absence of strong oxidative stress. This could relate to higher levels of endogenous SOD and CAT activities characteristic of moderately and highly paraquat-resistant genotypes. The response to lower paraquat concentrations evaluated as HSP70B accumulation was proportional to the level of genotype susceptibility to PQ. New evidence is provided that low-level oxidative stress impacts the antioxidant and HSP70B responses differently depending on the genotype resistance. In light of the still unresolved challenge for identification of reliable characters for screening of genotype resistance/susceptibility to oxidative stress, our study demonstrates that HSP70B accumulation could be used as an early marker for induced oxidative stress in the studied genotypes. The obtained results that the most pronounced differences in the antioxidant and HSP70B response were found between the two susceptible genotypes provoke us to convey future experiments with other susceptible genotypes.
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Affiliation(s)
- Stephka G Chankova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
| | - Evgeniya G Dimova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
| | - Zhana Mitrovska
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
| | - Daniela Miteva
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
| | - Dariya V Mokerova
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr., 33, Moscow 119071, Russia.
| | - Petranka A Yonova
- Bulgaria Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, Acad G. Bonchev Street, Building 21, 1113 Sofia, Bulgaria.
| | - Nadezhda P Yurina
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr., 33, Moscow 119071, Russia.
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Kopaskova M, Hadjo L, Yankulova B, Jovtchev G, Galova E, Sevcovicova A, Mucaji P, Miadokova E, Bryant P, Chankova S. Extract of Lillium candidum L. can modulate the genotoxicity of the antibiotic zeocin. Molecules 2011; 17:80-97. [PMID: 22269865 PMCID: PMC6268910 DOI: 10.3390/molecules17010080] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 11/28/2011] [Accepted: 12/12/2011] [Indexed: 11/16/2022] Open
Abstract
Lilium candidum L. extract (LE) is well known in folk medicine for the treatment of burns, ulcers, inflammations and for healing wounds. This work aims to clarify whether the genotoxic potential of the radiomimetic antibiotic zeocin (Zeo) could be modulated by LE. Our results indicate that LE exerts no cytotoxic, DNA-damaging and clastogenic activity in in Chlamydomonas reinhardtii, Pisum sativum L. and Hordeum vulgare L. test systems over a broad concentration range. Weak but statistically significant clastogenic effects due to the induction of micronuclei and chromosome aberrations have been observed in H. vulgare L. after treatment with 200 and 300 μg/mL LE. To discriminate protective from adverse action of LE different experimental designs have been used. Our results demonstrate that the treatment with mixtures of LE and Zeo causes an increase in the level of DNA damage, micronuclei and "metaphases with chromatid aberrations" (MwA). Clear evidence has been also obtained indicating that pretreatment with LE given 4 h before the treatment with Zeo accelerates the rejoining kinetics of Zeo-induced DNA damage in P. sativum L. and C. reinhardtii, and can decrease clastogenic effect of Zeo measured as frequencies of micronuclei and MwA in H. vulgare L. Here, we show for the first time that LE can modulate the genotoxic effects of zeocin. The molecular mode of action strongly depends on the experimental design and varies from synergistic to protective effect (adaptive response-AR). Our results also revealed that LE-induced AR to zeocin involves up-regulation of DSB rejoining in C. reinhardtii and P. sativum L. cells.
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Affiliation(s)
- Marcela Kopaskova
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynska dolina B-1, Bratislava 842 15, Slovakia
| | - Lina Hadjo
- Institute for Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, Sofia 1113, Bulgaria
| | - Bisera Yankulova
- Institute for Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, Sofia 1113, Bulgaria
| | - Gabriele Jovtchev
- Institute for Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, Sofia 1113, Bulgaria
| | - Eliska Galova
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynska dolina B-1, Bratislava 842 15, Slovakia
| | - Andrea Sevcovicova
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynska dolina B-1, Bratislava 842 15, Slovakia
| | - Pavel Mucaji
- Department of Pharmacognosy and Botany, Faculty of Pharmacy, Comenius University, Odbojarov 10, Bratislava 832 32, Slovakia
| | - Eva Miadokova
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynska dolina B-1, Bratislava 842 15, Slovakia
| | - Peter Bryant
- School of Biological and Medical Sciences, University of St. Andrews, St. Andrews KY16 9TS, Scotland, UK
| | - Stephka Chankova
- Institute for Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, Sofia 1113, Bulgaria
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Cheng GH, Wu N, Jiang DF, Zhao HG, Zhang Q, Wang JF, Gong SL. Increased levels of p53 and PARP-1 in EL-4 cells probably related with the immune adaptive response induced by low dose ionizing radiation in vitro. BIOMEDICAL AND ENVIRONMENTAL SCIENCES : BES 2010; 23:487-495. [PMID: 21315248 DOI: 10.1016/s0895-3988(11)60012-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Accepted: 08/20/2010] [Indexed: 05/30/2023]
Abstract
OBJECTIVE This paper is to explore the DNA repair mechanism of immune adaptive response (AR) induced by low dose radiation (LDR), the changes of mRNA levels and protein expressions of p53, ATM, DNA-PK catalytic subunit (DNA-PKcs) and PARP-1 genes in the LDR-induced AR in EL-4 cells. METHODS The apoptosis and cell cycle progression of EL-4 cells were detected by flow cytometry in 12 h after the cells received the pre-exposure of 0.075 Gy X-rays (inductive dose, D1) and the succeeding high dose irradiation (challenge dose, D2; 1.0, 1.5, and 2.0 Gy X-rays, respectively) with or without wortmannin (inhibitor of ATM and DNA-PK) and 3-aminobenzamid (inhibitor of PARP-1). And the protein expressions and mRNA levels related to these genes were detected with flow cytometry and reverse transcription-polymerase chain reaction in 12 h after irradiation with D2. RESULTS The mRNA and protein expressions of p53 and PARP-1 in EL-4 cells in the D1 + D2 groups were much lower than those in the D2 groups, and those of PARP-1 in the 3-AB + D2 and the 3-AB + D1 + D2 groups were much lower than those in the D2 and the D1 + D2 groups. The percentage of apoptotic EL-4 cells in the 3-AB + D1 + D2 groups was much higher than that in the D1 + D2 groups, that in the G₀/G₁ and the G₂ + M phases was much higher, and that in the S phase were much lower. Although the ATM and DNA-PKcs mRNA and protein expressions in wortmannin + D1 + D2 groups were much lower than those in the D1 + D2 groups, there were no significant changes in the apoptosis and cell cycle progression between the wortmannin + D1 + D2 and the D1 + D2 groups. CONCLUSION PARP-1 and p53 might play important roles in AR induced by LDR.
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Affiliation(s)
- Guang-Hui Cheng
- Department of Radiotherapy, China-Japan Union Hospital, Jilin University, Changchun 130033, Jilin, China
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Chankova SG, Yurina NP, Dimova EG, Ermohina OV, Oleskina YP, Dimitrova MT, Bryant PE. Pretreatment with heat does not affect double-strand breaks DNA rejoining in Chlamydomonas reinhardtii. J Therm Biol 2009. [DOI: 10.1016/j.jtherbio.2009.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Rea G, Esposito D, Damasso M, Serafini A, Margonelli A, Faraloni C, Torzillo G, Zanini A, Bertalan I, Johanningmeier U, Giardi MT. Ionizing radiation impacts photochemical quantum yield and oxygen evolution activity of Photosystem II in photosynthetic microorganisms. Int J Radiat Biol 2009; 84:867-77. [DOI: 10.1080/09553000802460149] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Dimova E, Dimitrova M, Miteva D, Mitrovska Z, Yurina NP, Bryant PE, Chankova S. Does single-dose cell resistance to the radio-mimetic zeocin correlate with a zeocin-induced adaptive response in Chlamydomonas reinhardtii strains? RADIATION AND ENVIRONMENTAL BIOPHYSICS 2009; 48:77-84. [PMID: 18956208 DOI: 10.1007/s00411-008-0199-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 10/09/2008] [Indexed: 05/27/2023]
Abstract
This study aimed to test whether a correlation exists between single-dose resistance to zeocin and the ability to develop a zeocin-induced adaptive response (AR) in Chlamydomonas reinhardtii strains. Three genotypes were used: wild type (WT) strain 137C and two strains (H-3 and AK-9-9), which are highly resistant to radiation based on survival studies. Based on a micro-colony assay, the strains could be arranged according to their single-dose resistance to zeocin as follows: AK-9-9 > H-3 > 137C. However, zeocin induced a similar level of DSB in strains AK-9-9, H-3 and 137C. The radio- and zeocin-resistant strains AK-9-9 and H-3 showed higher DSB rejoining capacity than the WT strain 137C, suggesting that DSB rejoining can at least partly account for different cell survival. Both WT and radio-resistant strains develop zeocin-induced AR involving increased DSB rejoining. The radio- and zeocin-resistant strains AK-9-9 and H-3 again showed higher DSB rejoining capacity than the WT strain 137C. The higher resistance of strains H-3 and AK-9-9 did not abrogate their ability to adapt, albeit with a smaller magnitude as compared to the WT strain. The obtained results characterize new radio-resistant C. reinhardtii strains, which enrich the collection of resistant C. reinhardtii strains.
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Affiliation(s)
- E Dimova
- Central Laboratory of General Ecology-BAS, Sofia, Bulgaria
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Dimova EG, Bryant PE, Chankova SG. Adaptive response: some underlying mechanisms and open questions. Genet Mol Biol 2008. [DOI: 10.1590/s1415-47572008000300002] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Chankova SG, Dimova E, Dimitrova M, Bryant PE. Induction of DNA double-strand breaks by zeocin in Chlamydomonas reinhardtii and the role of increased DNA double-strand breaks rejoining in the formation of an adaptive response. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2007; 46:409-16. [PMID: 17639449 DOI: 10.1007/s00411-007-0123-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2007] [Accepted: 06/26/2007] [Indexed: 05/02/2023]
Abstract
This study aimed to test the potential of the radiomimetic chemical zeocin to induce DNA double-strand breaks (DSB) and "adaptive response" (AR) in Chlamydomonas reinhardtii strain CW15 as a model system. The AR was measured as cell survival using a micro-colony assay, and by changes in rejoining of DSB DNA. The level of induced DSB was measured by constant field gel electrophoresis based on incorporation of cells into agarose blocks before cell lysis. This avoids the risk of accidental induction of DSB during the manipulation procedures. Our results showed that zeocin could induce DSB in C. reinhardtii strain CW15 in a linear dose-response fashion up to 100 microg ml(-1) which marked the beginning of a plateau. The level of DSB induced by 100 microg ml(-1) zeocin was similar to that induced by 250 Gy of gamma-ray irradiation. It was also found that, similar to gamma rays, zeocin could induce AR measured as DSB in C. reinhardtii CW15 and this AR involved acceleration of the rate of DSB rejoining, too. To our knowledge, this is the first demonstration that zeocin could induce AR in some low eukaryotes such as C. reinhardtii.
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Affiliation(s)
- S G Chankova
- Central Laboratory of General Ecology-BAS, Sofia, Bulgaria.
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