Radon is a naturally occurring radioactive gas and a significant contributor to environmental ionizing radiation. While its health impacts in humans are well documented, its effects on plant molecular biology remain largely unexplored. Myrosinase, a key enzyme in Capparis spinosa var. ovata and other Brassicas, is involved in plant defense against herbivores by hydrolyzing glucosinolate. This study investigates the impact of environmental radon exposure on the expression of the Myrosinase and TGG (Thioglucoside glucohydrolase) genes in Capparis spinosa var. ovata. Capparis spinosa var. ovata samples were collected from sites with different elevations and background radon levels in selected regions. Environmental radon concentrations were mapped using an alphabet PQ۲۰۰۰ Pro detector. The total RNA was extracted from leaf tissue, and cDNA of Myrosinase and TGG genes was synthesized for the real-time PCR (qRT-PCR) analysis. The level of genes expression was normalized for actin genes as a housekeeping gene and the relative change was analyzed using ۲−ΔCT method. Statistical differences were assessed by independent T-test. Radon-exposure against on Capparis spinosa var. ovata display an important upregulation of both Myrosinase and TGG genes compared to control. Myrosinase-related genes showed a notable increase in fold change, while
TGG gene expression was highly variable, but was largely high. These findings suggest that the environmental radon acts as a potent abiotic stressor, which triggers molecular defense reactions in the Capparis spinosa var. ovata. This study provides the first evidence that environmental radon exposure contributes to the expression of the significant defense-related genes in the Capparis spinosa var. ovata, which contains implications for plant adaptation, ecological interaction, and quality of plant-related products in radon-contaminate areas. As a result, radioactive environmental contaminants highlight the need for further research on the underlying molecular mechanisms of plant reactions.
