Crystal structure of the ternary complex of 14-3-3/Fusicoccin/PMA and methods for designing new herbicides

The present invention relates to a crystal of a ternary complex composed of the protein 14-3-3, a ligand thereof and a fragment of Plasma Membrane ATPase (PMA) comprising the coordinates of table 4 or coordinates which differ from the coordinates of table 4 by a root mean square deviation of the C-alpha atoms of less than 3 Angstrom, wherein (a) protein 14-3-3 consists of the amino acid sequence of SEQ ID NO: 1 or of the sequence of a species homolog; (b) the ligand is Fusicocdin; (c) PMA is a C-terminal peptide of up to 15 amino acid residues in length; comprising the amino acid sequence of SEQ ID NO: 2 or comprising the sequence of a species homolog. Moreover, the invention also relates to methods for obtaining crystals of 14-3-3 in ternary complex and to methods relating to the determination of said 14-3-3 crystal coordinates. In addition, the present invention relates to computer modeling of crystal coordinates, to methods for developing a ligand binding to the complex of protein 14-3-3 and PMA and to methods for identifying a potential ligand to the complex of 14-3-3 and PMA. Furthermore, the present invention relates to a method for identifying and selecting a protein or protein complex with increased affinity to a ligand, to nucleic acid molecules encoding PMA or 14-3-3 with decreased affinity to a ligand and to methods of generating transgenic plants encoding PMA or 14-3-3 with decreased affinity to said ligand. Finally, the present invention relates to a device for developing a ligand for the complex of PMA and 14-3-3 and to the use of said device.