Figure 3. Role of LcrQ in regulating the transcription of T3SS genes.

(A) Comparison of relative promoter activities of T3SS genes under T3SS inducible conditions in LcrQ over-expressed strain with YPIII carrying the pOVR200 plasmid. Promoters repressed by LcrQ were marked with red dot. (B) Secretion (Supernatant) and expression (Pellet) of T3SS effectors in LcrQ over-expressed and ΔlcrF strains under T3SS inducible conditions. RpoA was used as a loading control. (C) Secretion and expression of T3SS effectors in ΔlcrQ and LcrF over-expressed strains at 37°C with or without Ca²⁺. (D) & (E) Effects of LcrQ over-expression on the promoter activities of three LcrQ targets (yopE, lcrG and yopH) in YPIII ΔpYV and ΔlcrF strains.