Plants exposed to abiotic stresses such as drought, salinity, or extreme temperatures produce excessive amounts of harmful molecules known as reactive oxygen species (ROS). These molecules can damage proteins, cellular membranes, and DNA. To maintain cellular homeostasis, plants have developed enzymatic antioxidant systems, among which superoxide dismutases (SODs) play a key role. These enzymes catalyze the conversion of ROS into less toxic compounds. Based on the metal cofactor involved, SODs are classified into three main groups: Cu/ZnSOD, FeSOD, and MnSOD.
In this study, the researchers carried out a comprehensive analysis of the argan tree genome to identify and characterize genes encoding SODs. In total, nine SOD genes were identified and classified into three groups according to the metal cofactor involved. This classification was confirmed through analyses of their gene structures, evolutionarily conserved protein sequences essential for enzymatic function, as well as phylogenetic relationships with SODs from other plant species. In addition, analysis of the regulatory regions of these genes revealed the presence of several cis-regulatory elements associated with stress responses, suggesting a potential role of SOD genes in the adaptation of the argan tree to unfavorable environmental conditions.
Finally, 36 pairs of specific primers were designed to facilitate the analysis of gene expression in future experiments. Their efficiency and specificity were evaluated through in silico analyses, indicating satisfactory performance for subsequent applications.
Overall, this study provides a solid foundation for a better understanding of the role of SOD genes in the argan tree. These findings could ultimately contribute to the development of more stress-tolerant plants capable of better withstanding drought, salinity, and other environmental constraints.
Ref. Chahidi M., El Faqer A., Rabeh K. & Belkadi B., 2025 - Genome-wide survey of superoxide dismutase (SOD) genes in Argania spinosa L., an endemic tree species. Discover Plants (2025) 2:362 – https://doi.org/10.1007/s44372-025-00379-x
Posted by Jean-Paul Peltier.