Isolation and characterization of the caprine genomic β-lactoglobulin gene

Abstract

In order to obtain a mammary tissue-specific promoter, the genomic clones of P-lactoglobulin, one of the milk-specific proteins, were isolated from a caprine genomic library. The nucleotide sequence and structure of the caprine p-lactoglobulin gene is highly conserved among ruminant species. The functionality and mammary cell-specific expression of the caprine BLG promoter was examined in an in vitro cell culture system. Deletion analysis of the upstream regulatory sequence suggests that mammary tissue-specificity and hormonal inducibility may be mediated by a distal upstream regulatoiy sequence above ？109 bp rather than by a proximal promoter.