Molecular Cloning and Functional Characterization of Catalase in Stress Physiology, Innate Immunity, Testicular Development, Metamorphosis, and Cryopreserved Sperm of Pacific Abalone.

Catalase is a crucial enzyme of the antioxidant defense system responsible for the maintenance of cellular redox homeostasis. The aim of the present study was to evaluate the molecular regulation of catalase () in stress physiology, innate immunity, testicular development, metamorphosis, and cryopreserved sperm of Pacific abalone. gene was cloned from the digestive gland (DG) of Pacific abalone. The 2894 bp sequence of had an open reading frame of 1506 bp encoding 501 deduced amino acids. Fluorescence hybridization confirmed localization in the digestive tubules of the DG. was induced by different types of stress including thermal stress, HO induction, and starvation. Immune challenges with , lipopolysaccharides, and polyinosinic-polycytidylic acid sodium salt also upregulated mRNA expression and catalase activity. responded to cadmium induced-toxicity by increasing mRNA expression and catalase activity. Elevated seasonal temperature also altered mRNA expression. mRNA expression was relatively higher at the trochophore larvae stage of metamorphosis. Cryopreserved sperm showed significantly lower mRNA expression levels compared with fresh sperm. mRNA expression showed a relationship with the production of ROS. These results suggest that might play a role in stress physiology, innate immunity, testicular development, metamorphosis, and sperm cryo-tolerance of Pacific abalone.