SECOND MESSENGERS

• Adrenaline binds to its complementary, specific receptor site on the receptor protein, causing the receptor protein to change shape
• The shape change in the receptor protein is transmitted to the enzyme adenylate cyclase inside the cell, leading to a change in its tertiary structure
• The activated adenylate cyclase converts ATP to cyclic AMP (cAMP), which acts as a second messenger
• Large amounts of cAMP can be produced through this process
• cAMP binds to the enzyme protein kinase in the cytoplasm, changing the tertiary structure of the enzyme and exposing its active site, thereby activating the enzyme