Mitochondrial succinic-semialdehyde dehydrogenase of the gamma-aminobutyrate shunt is required to restrict levels of reactive oxygen intermediates in plants.

ABSTRACT: The gamma-aminobutyrate (GABA) shunt is a metabolic pathway that bypasses two steps of the tricarboxylic acid cycle, and it is present in both prokaryotes and eukaryotes. In plants the pathway is composed of the calcium/calmodulin-regulated cytosolic enzyme glutamate decarboxylase and the mitochondrial enzymes GABA transaminase and succinic-semialdehyde dehydrogenase (SSADH). The activity of the GABA shunt in plants is rapidly enhanced in response to various biotic and abiotic stresses. However the physiological role of this pathway remains obscure. To elucidate its role in plants, we analyzed Arabidopsis T-DNA knockout mutants of SSADH, the ultimate enzyme of the pathway. Four alleles of the ssadh mutation were isolated, and these exhibited a similar phenotype. When exposed to white light

SUBMITTER: Bouche N 

PROVIDER: S-EPMC164534 | biostudies-literature | 2003 May

REPOSITORIES: biostudies-literature