Steroid Hormones
Steroid hormones are small, lipid-soluble molecules that can easily pass though the membranes of cells. Examples are estrogen, testosterone, and various glucocorticoids.
Once in the cell:
Steroids bind to specific hormone receptors in the nucleus (or bind to receptors in the cytoplasm, and the hormone-receptor complex is transported into the nucleus).
The nuclear hormone-receptor complex binds to a specific site on the DNA, known as the “hormone response element” (HRE) enhancer.