Structure of the human apolipoprotein D gene promoter region.

A human genomic clone of 18.2 kbp encompassing the apolipoprotein D (apoD) exon-1 and 2 and 10 kbp of upstream sequence was isolated and characterized. DNA sequencing and primer extension analysis revealed a transcriptional initiation site located 27 bp downstream of a consensus TATA box sequence. The exon 1 was 66 bp long. Computer analysis of DNA sequence from positions -557 to +129 revealed some putative transcriptional regulatory elements including a stretch of (pyrimidine/purine)26 located from nucleotide -263 to nucleotide -212, which could potentially form Z-DNA. Steroid hormone regulatory elements were identified which may be related to the modulation of apoD gene expression by androgens and estrogens in vitro.