ISOLATION AND CHARACTERIZATION OF THE CAPRINE GENOMIC BETA-LACTOGLOBULIN GENE

In order to obtain a mammary tissue-specific promoter, the genomic clo nes of beta-lactoglobulin, one of the milk-specific proteins, were iso lated from a caprine genomic library. The nucleotide sequence and stru cture of the caprine beta-lactoglobulin gene is highly conserved among ruminant species. The functionality and mammary cell-specific express ion of the caprine BLG promoter was examined in an in vitro cell cultu re system. Deletion analysis of the upstream regulatory sequence sugge sts that mammary tissue-specificity and hormonal inducibility may be m ediated by a distal upstream regulatory sequence above -109 bp rather than by a proximal promoter.