A region in the steroid binding domain determines formation of the non-DNA-binding, 9 S glucocorticoid receptor complex.
This work was initiated to determine if a specific region of the glucocorticoid receptor determines the formation of the inactive (i.e. non-DNA-binding) 9 S form of the receptor recovered in cytosol preparations. It is known that the murine glucocorticoid receptor of the nti phenotype, which consists of only the carboxyl-terminal 40-kDa peptide containing the DNA-binding and steroid-binding domains separated by a short linker region, is recovered in hypotonic lysates as a 9 S heteromeric complex (Gehring, U., and Arndt, H. (1985) FEBS Lett. 179, 138-142). To further localize the domain required for formation of the 9 S complex, we have determined the sedimentation coefficients of receptors produced in COS-7 cells transfected with several mutants of the human glucocorticoid receptor gene. Deletion of the DNA-binding domain results in a 9 S complex that is somewhat less stable than the wild type receptor during sucrose gradient centrifugation. Deletion of the linker region yields a molybdate-stabilized 9 S complex, but deletion of the entire steroid-binding domain or internal deletion of the amino-terminal two-thirds of this domain yields receptors that are constitutive transcriptional activators and are present in cytosol only in the 4 S form. Taken together, these observations demonstrate that the steroid-binding domain contains the features required for formation of the 9 S heteromeric complex, and they are consistent with the proposal that the steroid-binding domain normally represses receptor function.
Pratt
W B
WB
Institut National de la Santé et de la Recherche Médicale U33, Université Paris-Sud, Bicêtre, France.
Jolly
D J
DJ
Pratt
D V
DV
Hollenberg
S M
SM
Giguere
V
V
Cadepond
F M
FM
Schweizer-Groyer
G
G
Catelli
M G
MG
Evans
R M
RM
Baulieu
E E
EE
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D004247:DNA / Q000378:metabolism; D006801:Humans; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids; D011965:Receptors, Glucocorticoid / Q000235:genetics* / Q000378:metabolism; D013045:Species Specificity; D014162:Transfection; D014222:Triamcinolone Acetonide / Q000378:metabolism
D046911:Macromolecular Substances; D011965:Receptors, Glucocorticoid; D004247:DNA; D014222:Triamcinolone Acetonide