The Expression of OsPLA2-III and OsPPO Genes in Rice (Oryza sativa L.) Under Fe Toxicity Stress.

Lipids are an important biomolecule in plants because of their structural and functional roles in plant cells. Moreover, they could act as signal molecules in the defense system of plants suffering from biotic and abiotic stresses. Furthermore, plants develop various tolerance strategies to cope with iron (Fe) toxicity, for example, by involving genes in the detoxification process and other mechanisms. Therefore, the objective of this research was to investigate the expression of OsPLA2-III and OsPPO genes during Fe stress conditions. It was carried out using two-week-old seedlings of two rice varieties, namely, IR64 (Fe-sensitive variety) and Pokkali (Fe-tolerant variety). The seedlings were treated with 400 ppm FeSO4.7H2O in the nutrient culture solution and compared with control that received 1 ppm FeSO4.7H2O. Furthermore, leaf bronzing, chlorophyll content and relative expression of OsPLA2-III and OsPPO genes were observed. An in-silico study was also performed to predict the interaction between OsPLA2-III and OsPPO proteins. The results showed that the Fe toxicity induced leaf bronzing, decreased leaf chlorophyll content, and increased the expression levels of OsPLA2-III and OsPPO genes. Therefore, both genes were suggested to have a role in plant tolerance mechanism during Fe toxicity stress through the lipid signaling pathway. [ABSTRACT FROM AUTHOR]