Glucocorticoid Receptor Signaling

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Glucocorticoid Receptor Signaling
SIGMA-ALDRICH
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Glucocorticoid Receptor Signaling The
glucocorticoid hormone, cortisol, passes through
the plasma membrane into the cytoplasm where it
binds to the specific, high-affinity
glucocorticoid receptor (GR). The resulting
complex is the non-DNA-binding oligomer of the
GR, in which the receptor is complexed with other
proteins. In this complex, the DNA-binding domain
of the receptor is bound by the heat shock
protein 90 (hsp90) dimer. Other proteins in this
complex include heat shock protein 70 (hsp70) and
FKBP52. Dissociation of the oligomeric complex
yields the free cortisol-receptor subunit in the
DNA-binding form. The activated receptor forms a
homodimer and is translocated to the nucleus
through the nucleopore. Inside the nucleus, the
receptor complex binds to specific DNA responsive
elements (GRE) to activate gene
transcription. References Bruner, K.L., et al.,
The unliganded mineralocorticoid receptor is
associated with heat shock proteins 70 and 90 and
the immunophilin FKBP-52. Recept. Signal
Transduct., 7, 85-98 (1997). Drouin, J., et al.,
Homodimer formation is rate-limiting for high
affinity DNA binding by glucocorticoid receptor.
Mol Endocrinol., 6, 1299-1309 (1992).