Signal transduction by G- protein-coupled receptors?

Signal transduction by G-protein-coupled receptors (GPCRs) involves a series of molecular events that ultimately lead to a cellular response.

When a ligand binds to a GPCR on the cell surface, it causes a conformational change in the receptor, which activates a G-protein that is associated with the receptor. The G-protein then activates an enzyme called adenylate cyclase, which produces a molecule called cyclic AMP (cAMP).

cAMP acts as a second messenger and activates protein kinase A (PKA), which phosphorylates target proteins in the cell, leading to a cellular response.

In addition to the cAMP pathway, GPCRs can also activate other signaling pathways, such as the phospholipase C pathway, which leads to the production of inositol trisphosphate (IP3) and diacylglycerol (DAG), and the activation of protein kinase C (PKC).

Overall, signal transduction by GPCRs is a complex process that involves the activation of multiple signaling pathways and ultimately leads to a variety of cellular responses, such as changes in gene expression, cell growth, and metabolism.