Loss-of-function of an Arabidopsis NADPH pyrophosphohydrolase, AtNUDX19, impacts on the pyridine nucleotides status and confers photooxidative stress tolerance.

ABSTRACT: The levels and redox states of pyridine nucleotides, such as NADP(H), regulate the cellular redox homeostasis, which is crucial for photooxidative stress response in plants. However, how they are controlled is poorly understood. An Arabidopsis Nudix hydrolase, AtNUDX19, was previously identified to have NADPH hydrolytic activity in vitro, suggesting this enzyme to be a regulator of the NADPH status. We herein examined the physiological role of AtNUDX19 using its loss-of-function mutants. NADPH levels were increased in nudx19 mutants under both normal and high light conditions, while NADP⁺ and NAD⁺ levels were decreased. Despite the high redox states of NADP(H), nudx19 mutants exhibited high tolerance to moderate light- or methylviologen-induced photooxidative stresses

SUBMITTER: Maruta T 

PROVIDER: S-EPMC5118724 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature