Expression of a cyclophilin OsCyp2-P isolated from a salt-tolerant landrace of rice in tobacco alleviates stress via ion homeostasis and limiting ROS accumulation

Abstract

Cyclophilins are a set of ubiquitous proteins present in all subcellular compartments, involved in a wide variety of cellular processes. Comparative bioinformatics analysis of the rice and Arabidopsis genomes led us to identify novel putative cyclophilin gene family members in both the genomes not reported previously. We grouped cyclophilin members with similar molecular weight and subtypes together in the phylogenetic tree which indicated their co-evolution in rice and Arabidopsis. We also characterized a rice cyclophilin gene, OsCyp2-P (Os02g0121300), isolated from a salinity-tolerant landrace, Pokkali. Publicly available massively parallel signature sequencing (MPSS) and microarray data, besides our quantitative real time PCR (qRT-PCR) data suggest that transcript abundance of OsCyp2-P is regulated under different stress conditions in a developmental and organ specific manner. Ectopic expression of OsCyp2-P imparted multiple abiotic stress tolerance to transgenic tobacco plants as evidenced by higher root length, shoot length, chlorophyll content, and K(+)/Na(+) ratio under stress conditions. Transgenic plants also showed reduced lipid peroxidase content, electrolyte leakage, and superoxide content under stress conditions suggesting better ion homeostasis than WT plants. Localization studies confirmed that OsCyp2-P is localized in both cytosol and nucleus, indicating its possible interaction with several other proteins. The overall results suggest the explicit role of OsCyp2-P in bestowing multiple abiotic stress tolerance at the whole plant level. OsCyp2-P operates via reactive oxygen species (ROS) scavenging and ion homeostasis and thus is a promising candidate gene for enhancing multiple abiotic stress tolerance in crop plants.

Physiological and Molecular Alterations Promoted by Schizotetranychus oryzae Mite Infestation in Rice Leaves

“…When overexpressed in Arabidopsis plants, ALDH induces abiotic stress tolerance and protection against lipid peroxidation and oxidative stress 97 . According to Kumari et al 98 , reduction of ROS accumulation also seems to be a mechanism by which cyclophilin proteins (also identified in our experiments, only in EI leaves) alleviate stress conditions. This was demonstrated in Pseudomonas syringae infection of tobacco plants 99 .…”

Expression of Pennisetum glaucum Eukaryotic Translational Initiation Factor 4A (PgeIF4A) Confers Improved Drought, Salinity, and Oxidative Stress Tolerance in Groundnut

“…Electrolyte leakage (EL) was determined by following the standard protocol described by Kumari et al (2015). Briefly, the leaf discs of control and transgenics were washed thoroughly with distilled water and incubated in 20 mL of deionized water for 2 h at 25°C.…”

“…In vitro localization of H 2 O 2 was determined by DAB assay as described by Kumari et al (2015). Leaves of control and transgenic plants were vacuum infiltrated in 1 mg/L freshly prepared DAB solution (pH 3.8) for about 10 min at room temperature.…”

Identification of low potassium stress-responsive proteins in tobacco (Nicotiana tabacum) seedling roots using an iTRAQ-based analysis

“…An overexpression of remorins in mulberry and Arabidopsis increases salt and dehydration tolerance (Checker and Khurana, 2013). One cyclophilin decreased; OsCYP20-2 increases environmental stress tolerance in tobacco and Arabidopsis (Kim et al, 2012), and OsCYP2-p in transgenic tobacco increases tolerance to salt stress by maintaining ion homeostasis and limiting ROS accumulation (Kumari et al, 2015). Low nitrogen levels induce a cyclophilin protein in tobacco (Yang et al, 2013), which suggests that this type of protein is important in tobacco plants under stress.…”