title: In vivo role of Arabidopsis arginase in arginine metabolism and abiotic stress response.
abstract: Nitric oxide (NO) and polyamines play essential roles in many developmental processes and abiotic stress responses in plants. NO and polyamines are metabolized from arginine through NO synthase (NOS) and arginine decarboxylase (ADC), respectively. Function of arginase, another important enzyme involved in arginine metabolism, in abiotic stress remains largely unknown. In the recent study, we have dissected the impact of arginase on arginine metabolism and abiotic stress responses through manipulating AtARGAHs expression. The results suggested that manipulation of arginase expression modulated accumulation of arginine and direct downstream products of arginine catabolism. AtARGAHs knockout lines exhibited increased accumulation of polyamines and NO and enhanced abiotic stress tolerance, while AtARGAHs overexpressing lines displayed the opposite results. Notably, we highlighted that Arabidopsis arginase plays distinctive and dual roles in the crosstalk between polyamines and NO signaling during abiotic stress responses, mediating both arginine metabolism and reactive oxygen species (ROS) accumulation. It is likely that accumulation of both NO and polyamines might activate abiotic stress responses in the plant.
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture; Wuhan Botanical Garden; Chinese Academy of Sciences; Wuhan, China.
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Shi
authors.forename: Zhu-Long
authors.initials: ZL
authors.lastname: Chan
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000502:physiology; D001119:Arginase / Q000378:metabolism*; D001120:Arginine / Q000378:metabolism*; D008954:Models, Biological; D013312:Stress, Physiological
chemical_list: D001120:Arginine; D001119:Arginase
keywords: abiotic stress; arginase; arginine; nitric oxide; polyamine; reactive oxygen species