Question

Describe hormone activate receptors in detail

Answer 1

Hormone activate receptors:

Steroid hormone receptors are the intracellular receptors that are found in the nucleus, cytosol, and also on the plasma membrane of target cells.They are generally intracellular receptors and initiate signal transduction for steroid hormones which lead to changes in gene expression over a time period of hours to days.

• Being lipids, steroid hormones enter the cell by simple diffusion across the plasma membrane. Thyroid hormones enter the cell by facilitated diffusion.
• The receptors exist either in the cytoplasm or nucleus, which is where they meet the hormone.

When hormone binds to receptor, a characteristic series of events occurs;

• Receptor activation is the term used to describe conformational changes in the receptor induced by binding hormone. The major consequence of activation is that the receptor becomes competent to bind DNA.
• Activated receptors bind to "hormone response elements", which are short specific sequences of DNA which are located in promoters of hormone-responsive genes. In most cases, hormone-receptor complexes bind DNA in pairs.
• Transcription from those genes to which the receptor is bound is affected. Most commonly, receptor binding stimulates transcription. The hormone-receptor complex thus functions as a transcription factor.