The present invention relates to a polypeptide which belongs to the
R3R3-type MYB family and which regulates the shikimate pathway towards
the production of benzenoids. The shikimate pathway is a biosynthesis
pathway through which the three essential aromatic amino acids tyrosine,
phenylalanine and tryptophan are synthesized in plants, bacteria and
fungi. The present invention provides for the first time a regulatory
protein in the shikimate pathway and a means to regulate the biosynthesis
of these three essential amino acids which cannot be produced by mammals.
At the same time, it opens up the way for the regulation of the
biosynthesis of aromatic and non-aromatic compounds which are derived
from these essential amino acids. A polypeptide or polynucleotide of the
invention may be used in a method for manipulating the transcript levels
of the genes of the shikimate pathway towards benzenoids for instance the
genes of 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (DAHPS),
5-enol-pyruvylshikimate-3-phosphate synthase (EPSPS), L-phenylalanine
ammonia-lyase (PAL) and chorismate mutase (CM).