Figure 4.

General structure of inflammasomes. 1. The intracellular receptor, containing a pyrin domain (PYD), on interaction with its ligand forms a disc-like structure. 2. The center of this structure interacts with ASC through PYD–PYD interactions. 3. The PYD domains of ASC interact with additional ASC PYD domains to form a cylindrical structure. 4. The CARD domains of caspase-1 monomers bind to the CARD of ASC. 5. Bound caspase-1 recruits additional caspase-1 molecules through CARD–CARD interactions, forming a fibril. A “mature” inflammasome is shown in Figure 5.