Catalase gene expression in response to auxin-mediated developmental signals.

The effect of auxin on maize catalase gene expression was examined at several different developmental stages during embryo and seedling development. All three catalase genes and their respective proteins were induced by both natural and synthetic auxin in immature embryos. Total catalase (CAT) activity increased dramatically in response to high concentrations of auxin, with CAT-2, which is not normally expressed at this stage, being the isozyme most responsible for the increase.