Molecule of the Month: Adenylyl Cyclase
Adenylyl cyclase creates second messengers to amplify signals from G-protein coupled receptors
Activating Ion Channels
Exploring the Structure
Adenylyl Cyclase and G-protein
Many of the early structures of adenylyl cyclase were determined using only the catalytic domain, given that membrane proteins are so difficult to crystallize. This structure (PDB ID 1cjk) shows how a key alpha helix in the activated G-protein binds to a pocket on the side of adenylyl cyclase. The catalytic domain is composed of two similar halves, with two similar neighboring pockets. One pocket binds to ATP and performs the cyclization reaction--in this structure, a modified, uncleavable form of ATP is bound in this pocket. The other pocket is thought to be regulatory, and has the plant stimulatory protein forskolin bound in it. To explore this structure in more detail, click on the image for an interactive Jsmol.
November 2020, David Goodselldoi:10.2210/rcsb_pdb/mom_2020_11