Regulation of dopamine-1A (D1A) receptor gene transcription.

The D1A receptor is expressed primarily in the brain and kidney. The D1A receptor gene has been cloned from human, rat and pig and is organized similarly in each species. The 5' flanking region of the D1A receptor gene is high in GC content, is TATA box-less and contains multiple Sp1 binding sites. Comparison and alignment of the nucleotide sequences within the 5' flanking and 5' untranslated regions of each gene indicates that the highest sequence identity is in the area centered approximately 100 bases upstream from the transcription start site. There are numerous binding sites for transcription factors, including Sp1 and AP-2, in the 5' flanking region. Approximately 200 bases upstream is a conserved cAMP regulatory element-like sequence. The conserved position of certain cis-acting elements in each gene suggests that the essential elements for regulated expression of the D1A receptor gene are contained within the first 300 bases of the 5' flanking region.