Adenililciklázat

Adenililciklázat, also known as adenylyl cyclase or AC, is an enzyme that catalyzes the formation of cyclic adenosine monophosphate (cAMP) from adenosine triphosphate (ATP). This reaction is a crucial step in many intracellular signaling pathways. Adenilyl cyclase enzymes are found in virtually all living organisms, from bacteria to humans, and play vital roles in regulating a wide range of cellular processes.

There are multiple isoforms of adenilyl cyclase, each with different regulatory properties and tissue-specific expression. These enzymes are typically activated by various extracellular signals, such as hormones and neurotransmitters, which bind to specific cell surface receptors. This binding often leads to the activation of a G protein, which then interacts with and stimulates adenilyl cyclase. Conversely, some signals can inhibit adenilyl cyclase activity.

The product of the adenilyl cyclase reaction, cAMP, acts as a second messenger. It diffuses within the cell and activates protein kinases, enzymes that phosphorylate other proteins, thereby altering their activity. This cascade of events ultimately leads to a specific cellular response, such as changes in gene expression, metabolism, or ion transport. The precise role of adenilyl cyclase and cAMP signaling varies depending on the cell type and the specific stimulus.