The invention relates to expression cassettes and vectors which contain constitutive promoters of plants and to the use of said expression cassettes or vectors for transgenic expression of nucleic acid sequences, preferably selection markers, in organisms, preferably in plants. The invention further relates to transgenic plants which have been transformed with said expression cassettes or vectors, to cultures, parts or propagation material derived therefrom and also to the use of same for the production of food- and feedstuffs, seed, pharmaceuticals or fine chemicals.