Overexpression of Rice CBS Domain Containing Protein Improves Salinity, Oxidative, and Heavy Metal Tolerance in Transgenic Tobacco

Abstract

We have recently identified and classified a cystathionine β-synthase domain containing protein family in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa L.). Based on the microarray and MPSS data, we have suggested their involvement in stress tolerance. In this study, we have characterized a rice protein of unknown function, OsCBSX4. This gene was found to be upregulated under high salinity, heavy metal, and oxidative stresses at seedling stage. Transgenic tobacco plants overexpressing OsCBSX4 exhibited improved tolerance toward salinity, heavy metal, and oxidative stress. This enhanced stress tolerance in transgenic plants could directly be correlated with higher accumulation of OsCBSX4 protein. Transgenic plants could grow and set seeds under continuous presence of 150 mM NaCl. The total seed yield in WT plants was reduced by 80%, while in transgenic plants, it was reduced only by 15-17%. The transgenic plants accumulated less Na+, especially in seeds and maintained higher net photosynthesis rate and Fv/Fm than WT plants under NaCl stress. Transgenic seedlings also accumulated significantly less H2O2 as compared to WT under salinity, heavy metal, and oxidative stress. OsCBSX4 overexpressing transgenic plants exhibit higher abiotic stress tolerance than WT plants suggesting its role in abiotic stress tolerance in plants.

Potassium contributes to zinc stress tolerance in peach (Prunus persica) seedlings by enhancing photosynthesis and the antioxidant defense system

“…Plants suffering from adverse abiotic stresses, including heavy-metal stress, produce excess internal reactive oxygen species (ROS), such as superoxide (O 2 -), hydrogen peroxide (H 2 O 2 ), and hydroxyl radicals (·OH -), which negatively elicit oxidative stress on cellular structures and metabolism (Foyer and Noctor, 2005;Turchi et al, 2012;Singh et al, 2012;Song et al, 2014a). In particular, plants can cope with oxidative stress via the antioxidant defense system.…”

“…The activity of antioxidant enzymes, i.e., superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), are correlated with plant tolerance to abiotic stresses (Wang et al, 2009;Huang et al, 2013). Previous reports illustrate that heavy metal toxicity results in oxidative damage to plants and that heavy metal tolerant plants possess high antioxidant enzyme activity (Turchi et al, 2012;Singh et al, 2012). In particular, proline accumulates heavily under stresses, providing the plants protection against damage by ROS, which helps to protect enzyme activities, stabilize protein synthesis machinery, or regulate cytosolic acidity (Choudhary et al, 2007).…”

Current trends in genetic manipulations to enhance abiotic and biotic stresses in tobacco

“…Such genes are typically overexpressed by using promoters to enhance their functions. For instance, transgenic tobacco plants overexpressing OsCBSX4 [a gene that produce a component of cystathionine β-synthase domain containing proteins (CDCPs)], obtained from rice (Oryza sativa L.) exhibited improved tolerance against salinity, heavy metals and oxidative stress (Singh et al, 2012). The higher accumulation of OsCBSX4 protein in OsCBSX4 overexpressing transgenic plants and the exhibition of higher abiotic stress tolerance than wild type (WT) plants suggest a role in abiotic stress tolerance in plants.…”

RAPD Profile Analysis of Single and Multigrain Aman Rice (Oryza sativa L.) Varieties Available in Bangladesh

“…Rice (Oryza sativa L.) is one of the most important cereal crops around the world, which provides the necessary daily calories and protein (15%) for more than half of the world's population (Singh et al 2012;Tyagi et al 2004, Maclean et al 2002. At least 114 countries grow rice and approximately 90% of the world's rice is grown in the Asia (Salim et al 2003, Paranthaman et al 2009).…”