Fig. 8

Using information about total subunit charge to track allosteric regulation in the 26S proteasome. a Surface representation of the structure of half of the 26S proteasome in state 1 [PDB: 4CR2]. The regulatory particle (red) enables the substrate to unfold and enter the core particle, which is made up of alpha (yellow) and beta rings (blue). b As the proteasome evolves from state 1 [PDB: 4CR2], through state 2 [PDB: 4CR3], to state 3 [PDB: 4CR4], the movement of the regulatory particle is translated into information which is exchanged with the core particle. The difference in total particle charge is a clear indication of regulation, despite the negligible movement observed in the core particle. c Information is transferred not just within each particle, but also vertically, between the alpha and the beta ring, and between the alpha ring and the regulatory particle. This suggests that vertical structures such as pairs of alpha-beta subunits may act in a correlated manner