The invention concerns tools, methods and compositions for modifying plants and/or protein expression in plants. The invention concerns in particular transcriptional promoters enabling specific expression in the trichomes, constructs containing said promoters, and their uses for genetically modifying cells, seeds or plants. The invention also concerns methods for producing transgenic plants expressing proteins or metabolites of interest. The invention is generally applicable to any plant having glandular trichomes, and to the expression of any protein of industrial interest, in particular therapeutic or phytosanitary.