Environmental Engineering Reference
In-Depth Information
Dex
(a)
Dex
HSP
90
GR
HSP
90
HSP
90
HSP
70
HSP
70
GR
HSP
70
HSP
70
HSP
90
GR
Dex
Cytoplasm
Dex
Dex
GR GR
Nucleus
DexDex
GR
GR
Basal
complex
(b)
Hormone
FIGURE 35.2
Glucocorticoid receptor (GR) biology. (a) At resting state, GR resides in the cytoplasm as a part of a multiprotein
complex with heat-shock proteins and immunophilins. (From Pratt, W.B. and D.O. Toft,
Endocr. Rev
., 18, 306,
1997.) Upon hormone stimulation, GR dissociates from this complex and migrates to the nucleus (cytoplasmic-
to-nuclear translocation). In the nucleus, the receptor interacts with GR regulatory elements (GREs) throughout
the genome, and regulates GR-mediated transcriptional responses. (b) Schematic representation of the trans-
location of the green luorescent protein (GFP)-tagged GR from the cytoplasm to the nucleus in the presence
of hormone or EDCs with glucocorticoid activity. This translocation is the basis of the biological screening for
detection of water contaminants interacting with a speciic nuclear receptor(s).
