Intronic steroid response elements in prostate binding protein genes.

Abbreviations used: GRE, glucocorticoid response element; ARE, androgen response element; MMTV, mouse mammary tumour virus; LTR, long terminal repeat. (MMTV) long terminal repeat (LTR) [2-41 or the tyrosine aminotransferase gene [ 51. However, androgen response elements (ARE) in androgen-responsive genes have been less easy to delimit. High-affinity androgen-receptor-binding regions have been detected in the promoter and first intron of the rat ventral prostate binding protein C3( 1 ) [6-81 and other constituent polypeptide genes [ 91. Affinity for androgen receptors has been tracked to a 450 bp fragment of the C3(1) intron containing two putative GRE-like elements: 5 '-TAGCCAAGTTGTTCT-3' in the non-coding strand and, centred 52 bp downstream in the coding strand, 5'-AGTACGTGATGTTCT-3' (see Fig. 1 ). Transfection analysis [lo] has attributed ARE status to the second element and none to the first. However, mobility shift analysis of androgen-receptor binding to restriction fragments labelled at either end (Fig. 1) indicates significant binding affinity in the first, non-coding strand, element. The abolition of binding to the second element can be attributed to its proximity