What is the role of receptors in mediating steroids and protein hormones?
Steroid hormones are lipids; they can cross directly through the cell's plasma membrane and nuclear membrane, binding to receptors. Receptor – hormone complex is formed and serves as a transcription factor; it promotes or inhibits the transcription of certain genes
Protein-based hormones (application on epinephrine) Epinephrine binds to a receptor called the G-protein receptor on the plasma membrane
G-protein activates adenylyl cyclase, converting ATP to cAMP (secondary messenger).
cAMP (second messenger) is a small water-soluble molecule that can quickly spread through the cytoplasm and relay signals throughout cells.
RP
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