Chlamydomonas as a model system for studying the relevance of plant genes for their involvement in multiple individual and combined stresses: a study unravelling PgCuZnSOD and PgAPX gene functions

The reactive oxygen species (ROS) including superoxide (O 2− ), hydrogen peroxide (H 2 O 2 ), and singlet oxygen (O 2− ), are the main molecules produced in excessive amounts under stress conditions, leading to cellular damage in plants. These ROS molecules should be effectively removed to impart stress tolerance. Enzymatic scavengers like superoxide dismutase, catalase, and peroxidases plays a significant role in scavenging ROS molecules. However, the functional validation of such genes cloned from hardy crops are very much limited. The present research demonstrates the synergistic effect of co-expressing multiple antioxidant genes encoding copper-zinc superoxide dismutase (Cu/Zn-SOD) and ascorbate peroxidase cloned from hardy crop Pennisetum glaucum to improve single and combined abiotic stress tolerance and also corroborates Chlamydomonas as a valuable model system for functional validation of multi genes, especially for understanding combined stress responses due to its rapid transformation process and molecular similarity to higher plants.