Nuclear extracts from mammary glands of lactating rats contain DNA binding protein(s) with high affinity to the region -125 to -85 of the rat alpha-lactalbumin promoter. The protected sequence is part of a mammary conserved sequence described by Hall et al. [(1987) Biochem. J. 242, 735-742]. Comparison of the DNA protein-binding sites in the 5′ flanking sequence of the rat alpha-lactalbumin and mouse whey acidic protein genes suggests that the consensus sequence 5‘-TGGCARNNWCKKC-3’ is the protein(s) recognition site. This binding site is part of a highly conserved region [consensus sequence, TGGCAGSCTCGGCST(G)YTCTCTCT(NTG)TGGCARA] present in the promoter of four whey protein genes.
