FIG. 2.

Wiring diagram of σ³² regulation. There are three primary modes of regulation as follows: (i) excess free DnaK/J and GroEL/S chaperones directly bind to and inactivate σ³²; (ii) the FtsH protease degrades σ³², with chaperones participating in this process; and (iii) temperature directly controls the rate of σ³² translation. Misfolded proteins titrate chaperones from these regulatory roles, allowing active σ³² to increase the synthesis of chaperones and proteases during conditions where they are needed.