The protein that makes cAMP is adenylyl cyclase.
Adenylyl Cyclase and cAMP Production
Adenylyl cyclase is a crucial enzyme in cell signaling. It catalyzes the conversion of ATP (adenosine triphosphate) into cAMP (cyclic adenosine monophosphate). This process is a key step in many signaling pathways, particularly those involving G protein-coupled receptors (GPCRs).
How Adenylyl Cyclase Works
The process typically involves the following steps, as described in the reference:
- GPCR Activation: Activated GPCRs trigger a change in the attached G protein complex.
- G Protein Activation: This conformational change leads the Gs alpha subunit of the G protein to exchange GDP (guanosine diphosphate) for GTP (guanosine triphosphate) and separate from the beta and gamma subunits.
- Adenylyl Cyclase Activation: The activated Gs alpha subunit then activates adenylyl cyclase.
- cAMP Production: Adenylyl cyclase rapidly converts ATP into cAMP.
Summary Table:
| Protein/Molecule | Role |
|---|---|
| GPCR | Receptor that initiates the signaling cascade. |
| G protein (Gs alpha) | Activates adenylyl cyclase. |
| Adenylyl Cyclase | Enzyme that produces cAMP from ATP. |
| ATP | Substrate used by adenylyl cyclase to make cAMP. |
| cAMP | Second messenger that mediates various cellular responses. |
In essence, adenylyl cyclase acts as a signal amplifier, quickly producing a large number of cAMP molecules in response to the initial GPCR activation. cAMP then goes on to activate other downstream targets, such as protein kinase A (PKA), to mediate cellular responses.
