In the cAMP signaling pathway, extracellular signals combine with corresponding receptors to regulate adenylate cyclase activity, and extracellular signals are transformed into intracellular signals through the change of cAMP level of the second messenger. CAMP signaling pathway is one of the ways of cell signaling pathway mediated by G protein-coupled receptor. The combination of stimulation signal pathway and AC leads to the increase of intracellular cAMP; Inhibitory signal pathway combined with AC can reduce intracellular cAMP.
Composition and functional characteristics of cAMP signal pathway
The composition of cAMP signal pathway includes membrane receptor, AC, cAMP, PKA and so on. Membrane receptors include G protein-coupled receptors (GPCR) and ion channel receptors. When a specific external stimulus acts on the receptor, AC will be activated, leading to the production of cAMP. CAMP molecules can bind to two CAMP binding domains in PKA subunits, release two catalytic subunits of PKA, and activate and phosphorylate downstream target proteins.
CAMP signaling pathway has a strong regulatory role and is widely involved in many physiological processes, such as cell differentiation, proliferation, apoptosis and metabolic regulation. In the nervous system, the activation of cAMP signaling pathway can promote synaptic transmission of neurons and enhance memory formation; In the cardiovascular system, the role of cAMP signaling pathway can regulate the contraction and relaxation process of the heart; In metabolism-related diseases such as diabetes and obesity, the regulation of cAMP signaling pathway is related to insulin secretion and energy metabolism.
In addition, cAMP signaling pathway is also very important for the regulation of immune system. On T cells, the activation of cAMP signaling pathway inhibits the activation of cells, thus exerting immune tolerance; On macrophages, the activation of cAMP signaling pathway inhibits the production of NO, thus playing an anti-inflammatory role.