1.1.1.53 metabolism key enzyme involved in the biosynthesis and activation of steroid hormones 762606 1.1.1.53 metabolism the enzyme mediates glucocorticoid catabolism in fish, important enzyme in cortisol catabolism 763470 1.1.1.53 physiological function in fish the enzyme acts during final oocyte and sperm maturation and plays a role in initiating gametogenesis, as well as serving other metabolic functions in fish 762606 1.1.1.53 physiological function isoform 20beta-HSD type 2 is involved in cortisol catabolism and stress response. The morpholino-induced knock-down of gene expression in zebrafish embryos reveals no developmental phenotype under normal culture conditions, but prominent effects are observed after a cortisol challenge. 20beta-Hydroxycortisone is not a physiological ligand for the zebrafish glucocorticoid or mineralocorticoid receptor but is excreted into the fish holding water 726321