Adenylyl cyclase

Adenylyl cyclase (also known as adenyl cyclase or adenylate cyclase) is an important enzyme that is involved in the cellular signaling process. It is responsible for converting adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP) and pyrophosphate.

Function

Adenylyl cyclase plays a crucial role in the G protein-coupled receptor signaling pathway. When a ligand binds to a G protein-coupled receptor, it causes a conformational change in the receptor, which allows it to act as a guanine nucleotide exchange factor (GEF). The GEF activity of the receptor promotes the exchange of guanosine diphosphate (GDP) for guanosine triphosphate (GTP) on the alpha subunit of the G protein. This exchange triggers the dissociation of the alpha subunit from the beta-gamma dimer, allowing the alpha subunit to interact with adenylyl cyclase and stimulate the production of cAMP.

Types

There are ten known isoforms of adenylyl cyclase in mammals, each with distinct properties and patterns of expression. These isoforms are categorized into four groups based on their regulation by G proteins and calcium.

Clinical significance

Mutations in the genes encoding adenylyl cyclase can lead to a variety of diseases. For example, mutations in the ADCY5 gene, which encodes adenylyl cyclase 5, have been associated with familial dyskinesia with facial myokymia, a rare genetic disorder characterized by involuntary movements.

See also

• G protein-coupled receptor
• Cyclic adenosine monophosphate
• Adenosine triphosphate