Ectopic expression of finger millet calmodulin confers drought and salinity tolerance in Arabidopsis thaliana

Abstract Drought and salinity are major environmental stresses which affect crop productivity and therefore are major hindrance in feeding growing population world-wide. Calcium (Ca2+) signalling plays a crucial role during the plant's response to these stress stimuli. Calmodulin (CaM), a crucial Ca2+sensor, is involved in transducing the signal downstream in various physiological, developmental and stress responses by modulating a plethora of target proteins. The role of CaM has been well established in the model plant Arabidopsis thaliana for regulating various developmental processes, stress signalling and ion transport. In the current study, we investigate the CaM of Eleusine coracana (common name finger millet, known especially for its drought tolerance and superior Ca2+ content). In-silico analysis showed that Eleucine calmodulin (EcCaM) has greater similarity to rice CaM as compared to Arabidopsis CaM due to the presence of highly conserved four EF-hand domains. To decipher the in planta function of EcCaM, we have adopted the gain-of-function approach by generating the 35S::EcCaM over-expression transgenic in Arabidopsis. Overexpression of EcCaM in Arabidopsis makes the plant tolerant to polyethylene glycol (PEG) induced drought and salt stress (NaCl) as demonstrated by post-germination based phenotypic assay, ion leakage, MDA and proline estimation, ROS detection under stressed and normal conditions. Moreover, EcCaM-overexpression leads to hypersensitivity towards exogenously applied ABA at the seed germination stage. These findings reveal that EcCaM mediates tolerance to drought and salinity stress. Also, our results indicate that EcCaM is involved in modulating ABA signalling. Summarizing our results, we report for the first time that EcCaM is involved in modulating plants response to stress and this information can be used for the generation of future-ready crops that can tolerate a wide range of abiotic stresses.

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Expression of Zinc Finger Protein Zat12 from Arabidopsis thaliana in Escherichia coli

Vietnam Journal of Agricultural Sciences ◽

10.31817/vjas.2020.3.1.03 ◽

2020 ◽

Vol 3 (1) ◽

pp. 504-511

Author(s):

Le Thi Tuyet Cham ◽

Vu Ngoc Thang ◽

Tran Anh Tuan ◽

Vu Thi Thuy Hang

Keyword(s):

Arabidopsis Thaliana ◽

Zinc Finger ◽

Stress Responses ◽

Zinc Finger Protein ◽

Expression System ◽

Direct Interaction ◽

Early Response ◽

In Planta ◽

Abiotic Stress Response ◽

Finger Protein

The C2H2 zinc finger protein ZAT12 has been classified as a plant core abiotic stress response gene in the early response to multiple stresses. ZAT12 links the iron deficiency and oxidative stress responses through the direct interaction with/and negative regulation of a central regulator - FIT. For further research on the regulation of the ZAT12 protein in planta, a huge quantity of ZAT12 proteins is required to inject into mice for the generation of ZAT12 antiserum. In this study, the gene encoding the ZAT12 protein from Arabidopsis thaliana was cloned into the expression vector - pETBlue-2 and then overexpressed in E. coli T7. A high expression level was indicated by SDS-PAGE. Immunoblot demonstrated successful expression using a bacterial expression system.

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Rice lectin protein Osr40c1 imparts drought tolerance by modulating OsSAM2, OsSAP8 and chromatin-associated proteins

10.1101/2020.04.19.049288 ◽

2020 ◽

Author(s):

Salman Sahid ◽

Chandan Roy ◽

Soumitra Paul ◽

Riddhi Datta

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Stress Responses ◽

Ectopic Expression ◽

In Planta ◽

Biotic And Abiotic Stress ◽

Polyamine Biosynthesis ◽

Protein Partners ◽

Associated Proteins ◽

Lectin Protein

AbstractLectin proteins play an important role in biotic and abiotic stress responses in plants. Although the rice lectin protein, Osr40c1, has been reported to be regulated by drought stress, the mechanism of its drought tolerance activity has not been studied so far. In this study, it has been depicted that expression of Osr40c1 gene correlates with the drought tolerance potential of various rice cultivars. Transgenic rice plants overexpressing Osr40c1 were significantly more tolerant to drought stress over the wild-type plants. Furthermore, ectopic expression of the Osr40c1 gene in tobacco yielded a similar result. Interestingly, the protein displayed a nucleo-cytoplasmic localization and was found to interact with a number of drought-responsive proteins like OsSAM2, OsSAP8, OsMNB1B, and OsH4. Fascinatingly, silencing of each of these protein partners led to drought susceptibility in the otherwise tolerant Osr40c1 expressing transgenic tobacco lines indicating that these partners were crucial for the Osr40c1-mediated drought tolerance in planta. Together, the present investigation delineated the novel role of Osr40c1 protein in imparting drought tolerance by regulating the chromatin proteins, OsMNB1B and OsH4, which presumably enables OsSAP8 to induce downstream gene expression. In addition, its interaction with OsSAM2 might induce polyamine biosynthesis thus further improving drought tolerance in plants.HighlightsA rice lectin protein, Osr40c1, plays a crucial role in imparting drought stress tolerance in plants by modulating OsSAM2 as well as the transcriptional regulators OsSAP8, OsMNB1B and OsH4.

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Low Mannitol Concentrations in Arabidopsis thaliana Expressing Ectocarpus Genes Improve Salt Tolerance

Plants ◽

10.3390/plants9111508 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1508

Author(s):

Pramod Rathor ◽

Tudor Borza ◽

Yanhui Liu ◽

Yuan Qin ◽

Sophia Stone ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Salt Tolerance ◽

Transgenic Plants ◽

Salinity Stress ◽

Stress Responses ◽

Molecular Mechanisms ◽

Ion Homeostasis ◽

Biotic And Abiotic Stress ◽

Expression Of Genes ◽

Wide Range

Mannitol is abundant in a wide range of organisms, playing important roles in biotic and abiotic stress responses. Nonetheless, mannitol is not produced by a vast majority of plants, including many important crop plants. Mannitol-producing transgenic plants displayed improved tolerance to salt stresses though mannitol production was rather low, in the µM range, compared to mM range found in plants that innately produce mannitol. Little is known about the molecular mechanisms underlying salt tolerance triggered by low concentrations of mannitol. Reported here is the production of mannitol in Arabidopsis thaliana, by expressing two mannitol biosynthesis genes from the brown alga Ectocarpus sp. strain Ec32. To date, no brown algal genes have been successfully expressed in land plants. Expression of mannitol-1-phosphate dehydrogenase and mannitol-1-phosphatase genes was associated with the production of 42.3–52.7 nmol g−1 fresh weight of mannitol, which was sufficient to impart salinity and temperature stress tolerance. Transcriptomics revealed significant differences in the expression of numerous genes, in standard and salinity stress conditions, including genes involved in K+ homeostasis, ROS signaling, plant development, photosynthesis, ABA signaling and secondary metabolism. These results suggest that the improved tolerance to salinity stress observed in transgenic plants producing mannitol in µM range is achieved by the activation of a significant number of genes, many of which are involved in priming and modulating the expression of genes involved in a variety of functions including hormone signaling, osmotic and oxidative stress, and ion homeostasis.

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Histone Methylation and Memory of Environmental Stress

Cells ◽

10.3390/cells8040339 ◽

2019 ◽

Vol 8 (4) ◽

pp. 339 ◽

Cited By ~ 22

Author(s):

Paola Fabrizio ◽

Steven Garvis ◽

Francesca Palladino

Keyword(s):

Environmental Stress ◽

Histone Methylation ◽

Stress Responses ◽

Transcriptional Response ◽

Epigenetic Inheritance ◽

Yeast Saccharomyces Cerevisiae ◽

Post Translational Modifications ◽

Wide Range ◽

Transcriptional Memory ◽

Response To Stress

Cellular adaptation to environmental stress relies on a wide range of tightly controlled regulatory mechanisms, including transcription. Changes in chromatin structure and organization accompany the transcriptional response to stress, and in some cases, can impart memory of stress exposure to subsequent generations through mechanisms of epigenetic inheritance. In the budding yeast Saccharomyces cerevisiae, histone post-translational modifications, and in particular histone methylation, have been shown to confer transcriptional memory of exposure to environmental stress conditions through mitotic divisions. Recent evidence from Caenorhabditis elegans also implicates histone methylation in transgenerational inheritance of stress responses, suggesting a more widely conserved role in epigenetic memory.

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Tolerance to, and Uptake and Degradation of 2,4,6-Trinitrotoluene (TNT) are Enhanced by the Expression of a Bacterial Nitroreductase Gene in Arabidopsis thaliana

Zeitschrift für Naturforschung C ◽

10.1515/znc-2005-3-412 ◽

2005 ◽

Vol 60 (3-4) ◽

pp. 272-278 ◽

Cited By ~ 34

Author(s):

Mami Kurumata ◽

Misa Takahashi ◽

Atsushi Sakamoto ◽

Juan L. Ramos ◽

Ales Nepovim ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Transgenic Plants ◽

Degradation Products ◽

Plant Genome ◽

Pcr Analysis ◽

Wild Type ◽

In Planta ◽

Gene Encoding ◽

Plant Body ◽

Wide Range

Abstract Arabidopsis thaliana was transformed with a gene encoding a nitroreductase (NTR, E.C. 1.6.99.7) with activity against a wide range of nitroaromatic compounds. The gene was transferred from Escherichia coli by an Agrobacterium-mediated in planta method. The obtained seeds were sowed to produce T1 plants, and they were assayed for the integration of the transgene in the plant genome. Transgenic plants that were positive with the PCR analysis were self-pollinated to produce T2 generation plants. Seven lines obtained were assayed for the NTR activity. While the noil-transformed wild-type plants showed no detectable NTR activity, the enzyme activity of the transgenic plant lines was approx. 20 times higher. Using the line with the highest NTR activity, the phytoremediation characteristics of plants against 2,4,6-trinitrotoluene (TNT) was investigated. While the wild-type plants did not grow in the presence of 0.1 mᴍ TNT, the transgenic plants grew almost normally in this condition. The uptake of TNT by seedlings of transgenic plants increased by 7 to 8 times when they were floated on TNT solution. HPLC analysis showed that the peak due to TNT taken up into plant body was much smaller in the transgenic plants as compared with that of the wild type, and that a number of peaks attributable to the degradation products of TNT, including 4-amino-2,6-dinitrotoluene, were detected in the extract from the transgenic plants. This indicates that the expression of bacterial NTR improved the capability of plants to degrade TNT.

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Rice lectin protein r40c1 imparts drought tolerance by modulating S-adenosylmethionine synthase 2, stress-associated protein 8 and chromatin-associated proteins

Journal of Experimental Botany ◽

10.1093/jxb/eraa400 ◽

2020 ◽

Vol 71 (22) ◽

pp. 7331-7346 ◽

Cited By ~ 2

Author(s):

Salman Sahid ◽

Chandan Roy ◽

Soumitra Paul ◽

Riddhi Datta

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Stress Responses ◽

Ectopic Expression ◽

In Planta ◽

Biotic And Abiotic Stress ◽

Protein Partners ◽

Stress Associated Protein ◽

Associated Proteins ◽

Lectin Protein

Abstract Lectin proteins play an important role in biotic and abiotic stress responses in plants. Although the rice lectin protein Osr40c1 has been reported to be regulated by drought stress, the mechanism of its drought tolerance activity has not been studied so far. In this study, it is shown that expression of the Osr40c1 gene correlates with the drought tolerance potential of various rice cultivars. Transgenic rice plants overexpressing Osr40c1 were significantly more tolerant to drought stress than the wild-type plants. Furthermore, ectopic expression of the Osr40c1 gene in tobacco yielded a similar result. Interestingly, the protein displayed a nucleo-cytoplasmic localization and was found to interact with a number of drought-responsive proteins such as S-adenosylmethionine synthase 2 (OsSAM2), stress-associated protein 8 (OsSAP8), DNA-binding protein MNB1B (OsMNB1B), and histone 4 (OsH4). Silencing of each of these protein partners led to drought sensitivity in otherwise tolerant Osr40c1-expressing transgenic tobacco lines indicating that these partners were crucial for the Osr40c1-mediated drought tolerance in planta. Moreover, the association of Osr40c1 with these partners occurred specifically under drought stress forming a multi-protein complex. Together, our findings delineate a novel role of Osr40c1 in imparting drought tolerance by regulating OsMNB1B, OsSAM2, and OsH4 proteins, which presumably enables OsSAP8 to induce downstream gene expression.

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