Activator for both CDC42 and RAC1 by directly engaging these Rho GTPases and acting as potent guanine nucleotide exchange factor (GEF). This activation results in actin cytoskeleton rearrangements and stimulates membrane ruffling, promoting bacterial entry into non-phagocytic cells. Also activates MAPK8, indicating that it is capable of stimulating signaling pathways that can lead to nuclear responses. Chaperone InvB is required for secretion and translocation of SopE. Secreted via the type III secretion system 1 (SPI-1 TTSS). Transcriptionally activated by InvF in association with SicA. Encoded within a prophage region, which is only present in very few Salmonella isolates. SopE-expressing S.typhimurium strains are associated with severe epidemics. Belongs to the GEF (guanine exchange factor) SopE family. SopE is not present in the complete genome strain LT2.