The alteration of mRNA expression of SOD and GPX genes, and proteins in tomato (Lycopersicon esculentum Mill) under stress of NaCl and/or ZnO nanoparticles

Hesham F Alharby; Ehab M R Metwali; Michael P Fuller; Amal Y Aldhebiani

doi:10.1016/j.sjbs.2016.04.012

The alteration of mRNA expression of SOD and GPX genes, and proteins in tomato (Lycopersicon esculentum Mill) under stress of NaCl and/or ZnO nanoparticles

Saudi J Biol Sci. 2016 Nov;23(6):773-781. doi: 10.1016/j.sjbs.2016.04.012. Epub 2016 Apr 30.

Authors

Hesham F Alharby¹, Ehab M R Metwali², Michael P Fuller³, Amal Y Aldhebiani¹

Affiliations

¹ Department of Biological Sciences, Faculty of Science, King Abdulaziz University, 21589 Jeddah, Saudi Arabia.
² Biological Science Department, Faculty of Science, University of Jeddah, 21589 Jeddah, Saudi Arabia; Botany Department, Faculty of Agriculture, Suez Canal University, 41522 Ismailia, Egypt.
³ School of Biological Sciences, Faculty of Science and Engineering, Plymouth University, Plymouth PL4 8AA, UK.

Abstract

Five cultivars of tomato having different levels of salt stress tolerance were exposed to different treatments of NaCl (0, 3 and 6 g L^-1) and ZnO-NPs (0, 15 and 30 mg L^-1). Treatments with NaCl at both 3 and 6 g L^-1 suppressed the mRNA levels of superoxide dismutase (SOD) and glutathione peroxidase (GPX) genes in all cultivars while plants treated with ZnO-NPs in the presence of NaCl, showed increments in the mRNA expression levels. This indicated that ZnO-NPs had a positive response on plant metabolism under salt stress. Superior expression levels of mRNA were observed in the salt tolerant cultivars, Sandpoint and Edkawy while the lowest level was detected in the salt sensitive cultivar, Anna Aasa. SDS-PAGE showed clear differences in patterns of protein expression among the cultivars. A negative protein marker for salt sensitivity and ZnO-NPs was detected in cv. Anna Aasa at a molecular weight of 19.162 kDa, while the tolerant cultivar Edkawy had two positive markers at molecular weights of 74.991 and 79.735 kDa.

Keywords: GPX, glutathione peroxidase; Gene expression; MW, molecular weight; NPs-ZnO, nanoparticles of zinc oxide; Nanoparticles; Polymorphism; RF, relative factor; RT-PCR, real time polymerase chain reaction; Real-time PCR; SDS–PAGE, sodium dodecyl sulfate–poly acrylamide gel electrophoresis; SOD, superoxide dismutase; Salt stress; Tomato; cDNA, complementary DNA.