T3SS Effector EseN Modulates Expression of Host Genes Involved in the Immune Response.

The type III secretion system (T3SS) effector EseN is encoded on the chromosome and is homologous to a family of T3SS effector proteins with phosphothreonine lyase activity. Previously we demonstrated that invasion activates extracellular signal-regulated kinases 1 and 2 (ERK1/2) early in the infection, which are subsequently inactivated by EseN. Comparative transcriptomic analysis showed a total of 753 significant differentially expressed genes in head-kidney-derived macrophages (HKDM) infected with an EseN mutant (∆EseN) compared to HKDM infected with wild-type (WT) strains.