NOVEL TARGETS FOR HERBICIDES AND TRANSGENIC PLANTS RESISTANT TO SAID HERBICIDES.

摘要

The invention concerns novel enzymes having an arogenate dehydrogenase activity, in particular arogenate dehydrogenase enzymes of plants, and the genes encoding said enzymes. The inventive arogenate dehydrogenase enzymes catalyze the last stage of the metabolic pathway of tyrosine biosynthesis, and constitute, as such, potential targets of herbicides. Hence the invention also concerns a method for identifying herbicide compounds targeting said enzymes, said herbicide compounds preventing tyrosine biosynthesis by being fixed on said enzymes. The invention further concerns transgenic plants tolerant to herbicide compounds targeting an enzyme involved in the tyrosine biosynthesis pathway, in particular an enzyme involved in the transformation of L-tyrosine prephenate, in particular an arogenate dehydrogenase enzyme. Said plants become tolerant by expression in their tissues of a prephenate dehydrogenase enzyme, said enzyme being insensitive to said herbicide compounds and enabling the plant to synthetize tyrosine despite being treated with said herbicide compounds.