We have characterized the promoter region of the murine Y₁ receptor gene by using transient transfection assays and transgenic mice. The gene encoding the Y₁ receptor subtype was isolated from a mouse genomic library and its 5’ flanking region was identified by primer extension and sequence analysis. Reporter gene assays demonstrated that the upstream region of this gene is able to direct specific expression of reporter genes in neuron-derived cells and that two decameric sequences for the binding of the NF-kB/Rel family of transcription factors may play a functional role in the regulation the Y₁ receptor gene expression. Furthermore we showed that in transgenic mice the promoter region of the murine Y₁ receptor was able to direct a CNS- and developmental stage-specific expression pattern. Y₁/LacZ transgenic mice represent a model to evaluate, in vivo, changes in Y₁ receptor gene transcription following, for instance, neuronal lesions or pharmacological treatments.