ATP binding to the C terminus of the Arabidopsis thaliana nitrate/proton antiporter, AtCLCa, regulates nitrate transport into plant vacuoles.

ABSTRACT: Nitrate, one of the major nitrogen sources for plants, is stored in the vacuole. Nitrate accumulation within the vacuole is primarily mediated by the NO(3)(-)/H(+) exchanger AtCLCa, which belongs to the chloride channel (CLC) family. Crystallography analysis of hCLC5 suggested that the C-terminal domain, composed by two cystathionine beta-synthetase motifs in all eukaryotic members of the CLC family is able to interact with ATP. However, interaction of nucleotides with a functional CLC protein has not been unambiguously demonstrated. Here we show that ATP reversibly inhibits AtCLCa by interacting with the C-terminal domain. Applying the patch clamp technique to isolated Arabidopsis thaliana vacuoles, we demonstrate that ATP reduces AtCLCa activity with a maximum inhibition of 60%. ATP inhi

SUBMITTER: De Angeli A 

PROVIDER: S-EPMC2785341 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature