Characterization of the mouse α1D-adrenergic receptor gene

alpha 1-Adrenergic receptors (alpha 1-ARs) play critical roles in the regulation of a variety of physiological processes. Increasing evidence suggests that multiple receptor subtypes of alpha 1-ARs regulate these physiological processes. Molecular cloning has identified three distinct cDNAs encoding alpha 1-AR subtypes (alpha 1A, alpha 1B and alpha 1D) that are structurally homologous. Among the alpha 1-AR subtypes, the function of the alpha 1D-AR remains unclear. In order to examine the physiological role of alpha 1D-AR, we cloned and characterized a gene for the mouse alpha 1D-AR. Using a mouse alpha 1D-AR cDNA as a probe, we isolated the gene for the mouse (alpha 1D-AR from a mouse genomic Library. The alpha 1D-AR consists of two exons and an intron that interrupts the coding region of the putative sixth transmembrane domain. The 5'-flanking region of exon 1 contains neither a TATA box nor a CAAT box but is high in GC content and contains several Spl binding sites (GC boxes). This pattern is similar to promoters described for other members of alpha 1-ARs. The untranslated region also contains putative cyclic AMP response elements. Isolation of this gene will allow further investigation, via gene knock-outs and deletion mutants, of the mechanisms of transcriptional regulation and a greater understanding of the physiological role of alpha 1D-AR.