title: The actin-polymerizing activity of SipA is not essential for Salmonella enterica serovar Typhimurium-induced mucosal inflammation.
abstract: Salmonella enterica serovar Typhimurium depends on type III secretion systems to inject effector proteins into host cells to promote bacterial invasion and to induce intestinal inflammation. SipA, a type III effector, is known to play important roles in both the invasion and the elicitation of intestinal inflammation. The actin-modulating activity of SipA has been shown to promote Salmonella entry into epithelial cells. To investigate whether the actin-modulating activity of SipA is required for its ability to induce an inflammatory response in vivo, we generated the SipA(K635A E637W) mutant, which is deficient in actin-modulating activity. Salmonella strains expressing the chromosomal SipA(K635A E637W) point mutation had reduced invasion abilities but still caused colitis similar to that caused by the wild-type strain in a mouse model of infection. Our data indicate that the SipA actin-polymerizing activity is not essential for the SipA-induced inflammatory response in the mouse model of infection.
authors: Department of Molecular Virology, Shanghai Medical College of Fudan University, Shanghai, People's Republic of China.
authors: Dongju
authors: D
authors: Li
authors: Xueqin
authors: X
authors: Wang
authors: Lu
authors: L
authors: Wang
authors: Daoguo
authors: D
authors: Zhou
mesh_terms: D000199:Actins / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004195:Disease Models, Animal; D006367:HeLa Cells / Q000382:microbiology; D006801:Humans; D007249:Inflammation / Q000209:etiology*; D007410:Intestinal Diseases / Q000382:microbiology* / Q000473:pathology; D007413:Intestinal Mucosa; D051379:Mice; D008807:Mice, Inbred BALB C; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017354:Point Mutation; D058105:Polymerization; D012480:Salmonella Infections / Q000150:complications* / Q000378:metabolism; D012486:Salmonella typhimurium / Q000472:pathogenicity*
chemical_list: D000199:Actins; D001426:Bacterial Proteins; D008840:Microfilament Proteins; C118287:SipA protein, Salmonella