Molecular interactions of steroid hormone receptor with its enhancer element: evidence for receptor dimer formation.
A steroid hormone responsive element (GRE/PRE), sufficient to confer glucocorticoid and progesterone inducibility when linked to a reporter gene, was used in band-shift assays to examine its molecular interactions with steroid hormone receptors. Both progesterone and glucocorticoid receptors bound directly and specifically to the GRE/PRE. The purine contact sites for both form A and form B chicken progesterone receptor, as well as those for rat glucocorticoid receptor, are identical. A peptide fragment produced in bacteria that primarily contain the DNA binding domain of the glucocorticoid receptor binds first to the TGTTCT half-site of the GRE/PRE, and a second molecule binds subsequently to the TGTACA (half-site) of the GRE/PRE in a cooperative manner. Utilizing the peptide fragment and the protein A-linked fragment, we demonstrated that the receptor interacts with its cognate enhancer as a dimer.
Tsai
S Y
SY
Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Carlstedt-Duke
J
J
Weigel
N L
NL
Dahlman
K
K
Gustafsson
J A
JA
Tsai
M J
MJ
O'Malley
B W
BW
D000818:Animals; D001483:Base Sequence; D002645:Chickens; D004742:Enhancer Elements, Genetic; D008745:Methylation; D008969:Molecular Sequence Data; D011108:Polymers; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000235:genetics*; D011980:Receptors, Progesterone / Q000235:genetics*
D011108:Polymers; D011965:Receptors, Glucocorticoid; D011980:Receptors, Progesterone