Figure 9.

FtsH1/3 Complex Facilitates a Full Transcriptional Response to Fe, P, Ci, and N Stress Conditions.

Under nutrient limitation, the FtsH1/3 complex enhances the expression of the Fur, NdhR, and/or Pho regulon by reducing the levels of transcription factors Fur and NdhR and of PhoU, a negative effector of the two-component system PhoB/R. The FtsH1/3 complex also enhances the transcriptional response of the NtcA regulon: by an unknown mechanism, it promotes P_II phosphorylation, enabling the formation of the PipX/NtcA complex, functioning as an activator of the NtcA regulon. These processes depend on the availability of the relevant nutrient. Being involved in several regulatory pathways, FtsH1/3 may function as a linker enabling the strength of transcriptional responses to be adjusted in response stress conditions in a coordinated manner. 2OG, 2-oxoglutarate.