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Measurement of Cyclic Guanosine Monophosphate (cGMP) in Solid Tissues using Competitive Enzyme-Linked Immunosorbent Assay (ELISA)
Published on: July 3, 2025
Biochemistry of soluble guanylate cyclase
Emily R Derbyshire1, Michael A Marletta
1University of California, Berkeley, CA, USA.
Handbook of Experimental Pharmacology
|December 18, 2008
Summary
Nitric oxide (NO), a signaling molecule, activates soluble guanylate cyclase (sGC) to produce cGMP. Heme-Nitric oxide and OXygen binding (H-NOX) proteins help explain NO
Area of Science:
- Biochemistry
- Molecular Biology
- Physiology
Background:
- Nitric oxide (NO) is a crucial diatomic gas with dual roles as a cytotoxic agent and a signaling molecule.
- Initially identified as endothelium-derived relaxing factor (EDRF), NO's signaling functions are now extensively studied.
- Soluble guanylate cyclase (sGC) is a key heme protein mediating cellular responses to NO.
Purpose of the Study:
- To elucidate the mechanism of NO activation of sGC.
- To understand the discrimination between NO and other diatomic gases like oxygen (O2) and carbon monoxide (CO) by sGC.
- To characterize Heme-Nitric oxide and OXygen binding (H-NOX) proteins as sGC homologues.
Main Methods:
- Biochemical studies investigating NO binding and sGC activation.
- Characterization of sGC-like H-NOX proteins.
- Analysis of cGMP synthesis from GTP.
Main Results:
- NO binds to sGC rapidly, increasing cGMP synthesis over 100-fold.
- sGC exhibits selectivity for NO over O2 and CO, crucial for its function in aerobic environments.
- H-NOX proteins share structural and functional similarities with sGC, aiding mechanistic understanding.
Conclusions:
- NO is a vital signaling molecule that potently activates sGC, leading to cGMP production.
- The selective activation of sGC by NO is essential for its physiological roles.
- H-NOX proteins provide valuable insights into the molecular mechanisms of NO signaling and gas discrimination.
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