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Biochemical Reconstitution of Steroid Receptor•Hsp90 Protein Complexes and Reactivation of Ligand Binding
Published on: September 21, 2011
Sex hormone-binding globulin is synthesized in target cells
S M Kahn1, D J Hryb, A M Nakhla
1Department of Medicine, St Luke's/Roosevelt Hospital Center, and College of Physicians and Surgeons, Columbia University, New York, New York 10019, USA. wr7@columbia.edu
The Journal of Endocrinology
|October 16, 2002
Summary
Sex hormone-binding globulin (SHBG) regulates steroid responses. SHBG mediates cell membrane steroid signaling via cAMP, independent of intracellular receptors.
Area of Science:
- Endocrinology
- Molecular Biology
- Cell Biology
Background:
- Sex hormone-binding globulin (SHBG) is a plasma protein regulating sex steroid availability.
- SHBG also participates in a non-classical steroid-signaling pathway.
- Classical steroid signaling involves intracellular receptors and transcription factors.
Purpose of the Study:
- To review the current knowledge of the SHBG gene.
- To elucidate the role of SHBG in non-classical steroid signaling pathways.
Main Methods:
- Literature review of studies on the SHBG gene.
- Analysis of research on SHBG's role in cell membrane steroid signaling.
- Focus on SHBG's cAMP-mediated signaling, excluding its plasma-binding function.
Main Results:
- SHBG mediates androgen and estrogen signaling at the cell membrane.
- This signaling pathway is independent of intracellular steroid receptors.
- SHBG utilizes cyclic adenosine monophosphate (cAMP) for signal transduction.
Conclusions:
- SHBG plays a critical role in steroid signaling beyond its plasma-binding function.
- SHBG represents a novel pathway for steroid hormone action at the cell surface.
- Understanding SHBG's gene and signaling mechanisms is crucial for comprehending steroid hormone regulation.
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