What is the role of an active receptor in a G protein-coupled pathway?

What is the role of an active receptor in a G protein-coupled pathway?

• A. To inhibit cellular proliferation
• B. To stimulate cellular proliferation
• C. To maintain metabolic balance
• D. To enhance apoptosis

Answer: (B)

In a G protein-coupled pathway, an active receptor plays a crucial role in stimulating cellular proliferation. When a ligand binds to the receptor, it activates the receptor, which then undergoes a conformational change. This change allows the receptor to interact with and activate associated G proteins on the inside of the cell membrane. Once activated, these G proteins can initiate a cascade of intracellular signaling pathways that often lead to increased gene expression and protein synthesis, which are essential for cellular proliferation. This process is fundamental in the regulation of growth and division of cells, supporting processes like tissue repair, immune responses, and overall organism development. While cellular proliferation is a key outcome of active receptor signaling in many contexts, not all cellular pathways driven by active receptors lead to proliferation, hence the other options are less relevant in this context.

In a G protein-coupled pathway, an active receptor plays a crucial role in stimulating cellular proliferation. When a ligand binds to the receptor, it activates the receptor, which then undergoes a conformational change. This change allows the receptor to interact with and activate associated G proteins on the inside of the cell membrane.

Once activated, these G proteins can initiate a cascade of intracellular signaling pathways that often lead to increased gene expression and protein synthesis, which are essential for cellular proliferation. This process is fundamental in the regulation of growth and division of cells, supporting processes like tissue repair, immune responses, and overall organism development.

While cellular proliferation is a key outcome of active receptor signaling in many contexts, not all cellular pathways driven by active receptors lead to proliferation, hence the other options are less relevant in this context.