What is the Origin of Genomic Hormone Action?

The concept originated from the discovery of intracellular hormone receptors in the mid-20th century, which provided the molecular explanation for the long-observed, delayed, and sustained effects of steroid hormones on target tissues. The term genomic specifically refers to the interaction with the cell's genome, the DNA.

What is the Mechanism of Genomic Hormone Action?

Lipid-soluble steroid hormones passively diffuse across the cell membrane and bind to their cognate nuclear receptors, causing a conformational change that activates the receptor complex. The activated hormone-receptor complex then binds to specific DNA sequences known as Hormone Response Elements (HREs) located in the promoter regions of target genes. This binding recruits co-activator or co-repressor proteins, modulating the rate of gene transcription, thereby altering the synthesis of specific proteins that mediate the hormone's physiological effects.

Genomic Hormone Action ∞ Area

Genomic Hormone Action

Meaning

The mechanism by which steroid hormones, such as estrogens, androgens, and glucocorticoids, exert their biological effects by directly influencing gene transcription and protein synthesis within the cell nucleus. This action involves the hormone binding to an intracellular receptor, which then translocates to the nucleus to regulate the expression of specific target genes. It represents the slower, but more sustained, pathway of hormonal signaling, contrasted with rapid non-genomic effects.