Figure 3.

Model of SigB regulation in response to stress in Listeria monocytogenes. The stressosome is composed of RsbR, RsbR paralogues, RsbS and RsbT proteins. In unstressed conditions, RsbT is predicted as sequestrated within core of complex. Different stress types lead to phosphorylation of RsbR and RsbS by kinase RsbT through unknown mechanisms. This phosphorylation event results in release of RsbT from core of stressosome, initiating downstream SigB activation cascade. Stress-induced release of RsbT activates RsbU phosphatase. RsbU dephosphorylates RsbV, which then binds with RsbW, thus facilitating SigB release. L. monocytogenes triggers SigB-dependent general stress response after exposure to diverse environmental conditions. This model highlights the mechanisms of stressosome activation with the most characterized stress conditions reported to date