The present invention relates to novel strategies for gradually decreasing the expression of genes by modifying the promoter sequence. Provided are methods for gradually decreasing the expression level of a nucleic acid molecule of interest in a cell, preferably in a plant cell, comprising the step of introducing at least one modification into a promoter sequence, wherein the modification disrupts a core promoter consensus sequence. Furthermore, the invention also provides methods for producing a cell or an organism, preferably a plant cell or a plant, having a decreased expression level of a nucleic acid molecule of interest. The invention also relates to a cell and an organism, preferably a plant cell and a plant, obtained by a method according to the invention.