Molecule of the Month: Apoptosomes
Apoptosomes make life or death decisions in cells
Cytochrome c Trigger
Exploring the Structure
Apoptosome (PDB entry 3iz8)
Apoptosome proteins are composed of several functional domains, each with a different role to play. The apoptosome from fruit flies is shown here, with the domains in different colors. At one end of the chain, there is a CARD domain (magenta) involved in caspase interaction and a nucleotide-binding domain (blue) that assists with assembly of the complex. At the other end of the chain are two "beta-propeller" domains (red) that grip cytochrome c and trigger formation of the complex. In between are several smaller domains (green and yellow) that coordinate action between the two ends. To explore the domains in more detail, click on the image for an interactive JSmol.
Topics for Further Discussion
- The inactive form of the nematode apoptosome is composed of two apoptosome subunits (CED-4) bound to a regulatory protein (CED-9). You can explore this structure in PDB entry 2a5y.
September 2014, David Goodselldoi:10.2210/rcsb_pdb/mom_2014_9