NR3C2, also known as Nuclear Receptor Subfamily 3 Group C Member 2 or mineralocorticoid receptor (MR), is a nuclear receptor protein that plays a key role in regulating electrolyte balance and blood pressure. It functions as a ligand-activated transcription factor primarily located in the cytoplasm of target cells. When bound to mineralocorticoid hormones such as aldosterone, NR3C2 undergoes a conformational change and translocates to the nucleus to exert its effects. Its primary function includes regulating sodium and potassium ion transport in the kidney, colon, and salivary glands.