Which hormone uses an intracellular receptor that, after ligand binding, acts as a transcription factor by binding to hormone response elements (HREs) in target gene promoters?
- A Glucagon
- B Cortisol ✓
- C Epinephrine
- D Insulin
Correct answer: B. Cortisol
Explanation
Cortisol (a steroid hormone) is lipophilic and crosses the plasma membrane to bind cytoplasmic glucocorticoid receptors (GR). The ligand-receptor complex translocates to the nucleus, dimerises, and binds GREs (glucocorticoid response elements) to regulate gene transcription. Glucagon, epinephrine, and insulin are hydrophilic hormones that signal through surface receptors (GPCR or RTK) because they cannot enter the cell.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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