What type of signaling is associated with steroid hormones?

What type of signaling is associated with steroid hormones?

• A. Rapid signaling through ion channels.
• B. Long-term regulation through transcription factors.
• C. Short-term signaling through G-proteins.
• D. Non-specific signaling through cell membranes.

Answer: (B)

Steroid hormones are typically associated with long-term regulation through transcription factors. This is because steroid hormones, such as estrogen and testosterone, are lipophilic molecules that easily pass through cell membranes. Once inside the target cell, they bind to specific intracellular receptors, which then undergo a conformational change and translocate to the nucleus. In the nucleus, the hormone-receptor complex interacts with specific DNA sequences, acting as a transcription factor that modulates gene expression. This process leads to changes in the production of proteins that can have long-lasting effects on the cell, influencing processes such as growth, metabolism, and reproduction. This mechanism contrasts sharply with rapid signaling pathways, which typically involve immediate responses like those mediated by ion channels or G-proteins, as they operate on a much faster timescale and do not typically involve direct changes in gene expression. Thus, the correct association of steroid hormones with long-term regulatory mechanisms through transcription factors reflects their role in facilitating sustained physiological changes in target cells.

Steroid hormones are typically associated with long-term regulation through transcription factors. This is because steroid hormones, such as estrogen and testosterone, are lipophilic molecules that easily pass through cell membranes. Once inside the target cell, they bind to specific intracellular receptors, which then undergo a conformational change and translocate to the nucleus.

In the nucleus, the hormone-receptor complex interacts with specific DNA sequences, acting as a transcription factor that modulates gene expression. This process leads to changes in the production of proteins that can have long-lasting effects on the cell, influencing processes such as growth, metabolism, and reproduction. This mechanism contrasts sharply with rapid signaling pathways, which typically involve immediate responses like those mediated by ion channels or G-proteins, as they operate on a much faster timescale and do not typically involve direct changes in gene expression.

Thus, the correct association of steroid hormones with long-term regulatory mechanisms through transcription factors reflects their role in facilitating sustained physiological changes in target cells.