Abstract: Described and claimed are recombinant DNA molecules including the promoter region of the sel-12 gene of Caenorhabditis elegans (C. elegans) or promoter regions of genes homologous to the sel-12 gene, being capable of conferring expression of a heterologous DNA sequence in all neural cells, such as at all stages of development. Vectors including such recombinant DNA molecules are provided. Described and claimed also are pharmaceutical and diagnostic compositions as well as kits including the aforementioned recombinant DNA molecules and vectors. Furthermore, transgenic non-human animals, including the aforesaid recombinant DNA molecules or vectors stably integrated into their genome and their use for the identification of substances capable of complementing a neuronal disorder are described and claimed.