Mechanism of amino acid secretion from plant cells

• Applicant: Professor Dr. Guillaume Pilot
• Subject Area: Plant Physiology
• Term: from 2004 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5437691

Amino acid transport in plants allows the exchange of organic nitrogen between the various organs. The import mechanism is mediated by specific transporters and is well characterized, while the export mechanism is not identified. From the screening of an activation tagged library of Arabidopsis, we isolated two dominant mutants (Glutamine Dumper1, gdu1D) that secrete glutamine from the hydathodes. The physiological study of gdu1-1D suggests that glutamine export from the cells is increased upon over-expression of a novel gene, GDU1. GDU1 encodes a membrane protein with an unknown function. The aim of this project is to decipher the role of GDU1 in the plant, which may enable to unveil the mechanism of glutamine export, and potentially amino acid export, from the cell. We want to identify potential interacting partners of GDU1 using both biochemical and genetic approaches, in order to provide additional clues about the role of GDU1. In parallel, we want to study the physiological response of the plant to the enhanced GDU1-induced amino acid export from the cells.

• DFG Programme: Research Grants