title: Glutamine Induces the N-Dependent Accumulation of mRNAs Encoding Phosphoenolpyruvate Carboxylase and Carbonic Anhydrase in Detached Maize Leaf Tissue.
abstract: We have used detached leaves to study the N-dependent control of expression of phosphoenolpyruvate carboxylase (PEPC) and carbonic anhydrase (CA) genes in maize (Zea mays L. cv Golden Cross Bantam T51). Following supplementation with an N-source and zeatin, PEPC and CA mRNA levels increased in leaves detached from N-deficient maize plants. Addition of methionine sulfoximine (MSX), a specific inhibitor of glutamine synthetase, inhibited the nitrate-dependent increase of PEPC and CA mRNA but did not affect the glutamine-dependent increase of PEPC and CA mRNA levels. Glutamine levels in detached maize leaves treated with various N sources in the presence or absence of MSX correlated with the levels of PEPC and CA mRNA. We conclude that glutamine is the most likely effector for controlling the N-dependent expression of PEPC and CA in maize plants.
authors.affiliation: Department of Agricultural Chemistry, School of Agriculture, Nagoya University, Nagoya 464-01, Japan.
authors.forename: B
authors.initials: B
authors.lastname: Sugiharto
authors.forename: I
authors.initials: I
authors.lastname: Suzuki
authors.forename: J N
authors.initials: JN
authors.lastname: Burnell
authors.forename: T
authors.initials: T
authors.lastname: Sugiyama