Regulatory regions in the rat lactase-phlorizin hydrolase gene that control cell-specific expression.

Objectives: Lactase-phlorizin hydrolase (LPH) is an enterocyte-specific gene whose expression has been well-characterized, not only developmentally but also along the crypt-villus axis and along the length of the small bowel. Previous studies from the authors' laboratory have demonstrated that 2 kb of the 5'-flanking region of the rat LPH gene control the correct tissue, cell, and crypt-villus expression in transgenic animals.

Methods: To examine further the regulation conferred by this region, protein-DNA interactions were studied using DNase I footprint analyses in LPH-expressing and nonexpressing cell lines.