SbMYB15 transcription factor mitigates cadmium and nickel stress in transgenic tobacco by limiting uptake and modulating antioxidative defence system

2019 ◽  
Vol 46 (8) ◽  
pp. 702 ◽  
Author(s):  
Komal K. Sapara ◽  
Jackson Khedia ◽  
Parinita Agarwal ◽  
Doddabhimappa R. Gangapur ◽  
Pradeep K. Agarwal
Keyword(s):  
Reactive Oxygen Species ◽  
Heavy Metal ◽  
Transgenic Tobacco ◽  
Cell Fate ◽  
Metal Tolerance ◽  
Heavy Metal Tolerance ◽  
Reactive Oxygen ◽  
Transcript Expression ◽  
Oxygen Species ◽  
Salicornia Brachiata

Plants require different inorganic minerals in an appropriate amount for growth; however, imbalance can limit growth and productivity. Heavy metal accumulation causes toxicity and generates signalling crosstalk with reactive oxygen species (ROS), phytohormones, genes and transcription factors (TFs). The MYB (myeloblastoma) TFs participate in plant processes such as metabolism, development, cell fate, hormone pathways and responses to stresses. This is the first report towards characterisation of R2R3-type MYB TF, SbMYB15, from succulent halophyte Salicornia brachiata Roxb. for heavy metal tolerance. The SbMYB15 showed >5-fold increased transcript expression in the presence of CdCl2 and NiCl2•6H2O. The constitutive overexpression of SbMYB15 conferred cadmium and nickel tolerance in transgenic tobacco, with improved growth and chlorophyll content. Further, the transgenics showed reduced generation of reactive oxygen species (H2O2 and O2•−) as compared with the wild-type (WT) with both Cd2+ and Ni2+ stress. Transgenics also showed low uptake of heavy metal ions, increased scavenging activity of the antioxidative enzymes (CAT and SOD) and higher transcript expression of antioxidative genes (CAT1 and MnSOD). Thus, the present study signifies that SbMYB15 can be deployed for developing heavy metal tolerance in crop plants via genetic engineering.

scholarly journals Nitric Oxide Enhances Cytotoxicity of Lead by Modulating the Generation of Reactive Oxygen Species and Is Involved in the Regulation of Pb2+ and Ca2+ Fluxes in Tobacco BY-2 Cells

Plants ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 403 ◽  
Author(s):  
Jiaye Wu ◽  
Yue Zhang ◽  
Ruizhi Hao ◽  
Yuan Cao ◽  
Xiaoyi Shan ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Reactive Oxygen Species ◽  
Heavy Metal ◽  
Cell Death ◽  
Calcium Homeostasis ◽  
Reactive Oxygen ◽  
Ros Generation ◽  
Plant Responses ◽  
Oxygen Species ◽  
In Cells

Lead is a heavy metal known to be toxic to both animals and plants. Nitric oxide (NO) was reported to participate in plant responses to different heavy metal stresses. In this study, we analyzed the function of exogenous and endogenous NO in Pb-induced toxicity in tobacco BY-2 cells, focusing on the role of NO in the generation of reactive oxygen species (ROS) as well as Pb2+ and Ca2+ fluxes using non-invasive micro-test technology (NMT). Pb treatment induced BY-2 cell death and rapid NO and ROS generation, while NO burst occurred earlier than ROS accumulation. The elimination of NO by 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) resulted in a decrease of ROS, and the supplementation of NO by sodium nitroprusside (SNP) caused an increased accumulation of ROS. Furthermore, the addition of exogenous NO stimulated Pb2+ influx, thus promoting Pb uptake in cells and aggravating Pb-induced toxicity in cells, whereas the removal of endogenous NO produced the opposite effect. Moreover, we also found that both exogenous and endogenous NO enhanced Pb-induced Ca2+ effluxes and calcium homeostasis disorder. These results suggest that exogenous and endogenous NO played a critical regulatory role in BY-2 cell death induced by Pb stress by promoting Pb2+ influx and accumulation and disturbing calcium homeostasis.

scholarly journals Molecular Mechanism of Heavy Metal Toxicity and Tolerance in Plants: Central Role of Glutathione in Detoxification of Reactive Oxygen Species and Methylglyoxal and in Heavy Metal Chelation

2012 ◽  
Vol 2012 ◽  
pp. 1-37 ◽  
Author(s):  
Mohammad Anwar Hossain ◽  
Pukclai Piyatida ◽  
Jaime A. Teixeira da Silva ◽  
Masayuki Fujita
Keyword(s):  
Reactive Oxygen Species ◽  
Heavy Metal ◽  
Antioxidant Defense ◽  
Plant Cells ◽  
Reactive Oxygen ◽  
Antioxidant Defense System ◽  
Peroxidation Of Lipids ◽  
Oxygen Species ◽  
Defense System ◽  
Glyoxalase System

Heavy metal (HM) toxicity is one of the major abiotic stresses leading to hazardous effects in plants. A common consequence of HM toxicity is the excessive accumulation of reactive oxygen species (ROS) and methylglyoxal (MG), both of which can cause peroxidation of lipids, oxidation of protein, inactivation of enzymes, DNA damage and/or interact with other vital constituents of plant cells. Higher plants have evolved a sophisticated antioxidant defense system and a glyoxalase system to scavenge ROS and MG. In addition, HMs that enter the cell may be sequestered by amino acids, organic acids, glutathione (GSH), or by specific metal-binding ligands. Being a central molecule of both the antioxidant defense system and the glyoxalase system, GSH is involved in both direct and indirect control of ROS and MG and their reaction products in plant cells, thus protecting the plant from HM-induced oxidative damage. Recent plant molecular studies have shown that GSH by itself and its metabolizing enzymes—notably glutathione S-transferase, glutathione peroxidase, dehydroascorbate reductase, glutathione reductase, glyoxalase I and glyoxalase II—act additively and coordinately for efficient protection against ROS- and MG-induced damage in addition to detoxification, complexation, chelation and compartmentation of HMs. The aim of this review is to integrate a recent understanding of physiological and biochemical mechanisms of HM-induced plant stress response and tolerance based on the findings of current plant molecular biology research.

scholarly journals Ecotype-Specific Pathways of Reactive Oxygen Species Deactivation in Facultative Metallophyte Silene vulgaris (Moench) Garcke Treated with Heavy Metals

Antioxidants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 102 ◽  
Author(s):  
Ewa Muszyńska ◽  
Mateusz Labudda ◽  
Adam Kral
Keyword(s):  
Heavy Metals ◽  
Reactive Oxygen Species ◽  
Metal Tolerance ◽  
Reactive Oxygen ◽  
Enzymatic Antioxidants ◽  
Oxygen Species ◽  
Silene Vulgaris ◽  
Ros Scavenging ◽  
Natural Habitats

This research aimed to indicate mechanisms involved in protection against the imbalanced generation of reactive oxygen species (ROS) during heavy metals (HMs) exposition of Silene vulgaris ecotypes with different levels of metal tolerance. Specimens of non-metallicolous (NM), calamine (CAL), and serpentine (SER) ecotypes were treated in vitro with Zn, Pb, and Cd ions applied simultaneously in concentrations that reflected their contents in natural habitats of the CAL ecotype (1× HMs) and 2.5- or 5.0-times higher than the first one. Our findings confirmed the sensitivity of the NM ecotype and revealed that the SER ecotype was not fully adapted to the HM mixture, since intensified lipid peroxidation, ultrastructural alternations, and decline in photosynthetic pigments’ content were ascertained under HM treatment. These changes resulted from insufficient antioxidant defense mechanisms based only on ascorbate peroxidase (APX) activity assisted (depending on HMs concentration) by glutathione-S-transferase (GST) and peroxidase activity at pH 6.8 in the NM ecotype or by GST and guaiacol-type peroxidase in the SER one. In turn, CAL specimens showed a hormetic reaction to 1× HMs, which manifested by both increased accumulation of pigments and most non-enzymatic antioxidants and enhanced activity of catalase and enzymes from the peroxidase family (with the exception of APX). Interestingly, no changes in superoxide dismutase activity were noticed in metallicolous ecotypes. To sum up, the ROS scavenging pathways in S. vulgaris relied on antioxidants specific to the respective ecotypes, however the synthesis of polyphenols was proved to be a universal reaction to HMs.

scholarly journals Nox, Reactive Oxygen Species and Regulation of Vascular Cell Fate

Antioxidants ◽  
2017 ◽  
Vol 6 (4) ◽  
pp. 90 ◽  
Author(s):  
Denise Burtenshaw ◽  
Roya Hakimjavadi ◽  
Eileen Redmond ◽  
Paul Cahill
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Fate ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Vascular Cell

scholarly journals Level of reactive oxygen species induced by p21WAF(1)/CIP(1)is critical for the determination of cell fate

2009 ◽  
Vol 100 (7) ◽  
pp. 1275-1283 ◽  
Author(s):  
Takafumi Inoue ◽  
Kiyoko Kato ◽  
Hidenori Kato ◽  
Kazuo Asanoma ◽  
Ayumi Kuboyama ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Fate ◽  
Reactive Oxygen ◽  
Oxygen Species

Overexpression of Triticum durum TdAnn12 gene confers stress tolerance through scavenging reactive oxygen species in transgenic tobacco

2019 ◽  
Vol 46 (10) ◽  
pp. 885 ◽  
Author(s):  
Rania Ben Saad ◽  
Marwa Harbaoui ◽  
Walid Ben Romdhane ◽  
Nabil Zouari ◽  
Khong N. Giang ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Stress Tolerance ◽  
Transgenic Tobacco ◽  
Abiotic Stresses ◽  
Triticum Durum ◽  
Antioxidant Activities ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Stress Related Genes ◽  
Triticum Durum Desf

Plant annexins are proteins with multiple functions and roles in plant development and responses to abiotic stresses. We report here the functional analysis of the TdAnn12 annexin protein isolated from Triticum durum Desf. We have previously shown that TdAnn12 expression is highly induced by different abiotic stresses. In the present study, to investigate the physiological and biochemical stress-induced responses, we overexpressed TdAnn12 in tobacco. We demonstrate that transgenic tobacco plants expressing TdAnn12 exhibited enhanced tolerance to salt, osmotic stress and H2O2 at the seedling stage. Under greenhouse conditions, these plants showed tolerance to drought and salt stresses. Moreover, scavenging reactive oxygen species (ROS), higher chlorophyll content, lower lipid peroxidation levels and increased antioxidant activities (peroxidase, catalase and superoxide dismutase) were observed. Finally, accumulation of TdAnn12 in tobacco positively affects the regulation of some stress-related genes (MnSOD, APX1, CAT1, P5CS, NHX1, SOS1 and DREB1A). TdAnn12 interacts directly or indirectly with stress-related genes that could stimulate an adaptive potential to gain tolerance which is not present in non-transgenic (NT) plants. Our results clearly show that overexpression of TdAnn12 in transgenic tobacco improves stress tolerance through the removal of ROS.

Sign in / Sign up

Export Citation Format

Share Document