Preferred Label : Salmonella Pathway;
NCIt related terms : How does salmonella hijack a cell;
Alternative definition : BIOCARTA: Pathogenic Salmonella enter cells such as those of the intestinal epithelium
by altering cellular cytoskeletal structure and inducing membrane ruffling of the
infected cell. Salmonella is able to alter the cytoskeleton and membrane through the
action of secreted bacterial Sip proteins, SopE, SopB, and SptP that are inserted
into the cytosol of the infected cell. Sip proteins encoded by Salmonella are required
for the action of SopE and for the invasion of epithelial cells. SipA stabilizes actin
filaments, inducing membrane ruffling and perhaps focusing membrane changes where
bacteria are localized to allow their entry. SipC produces a similar effect on actin
filaments and cytoskeletal structure. SopE acts as an exchange factor on Rac1 and
Cdc42, two GTPases in the Rho family that regulate actin cytoskeleton. The activation
of Rac2 and Cdc42 by Salmonella SopE induces changes in cytoskeleton structure that
allow bacterial entry into the cell. SopB is another salmonella protein that acts
as an inositol polyphosphate phosphatase and also stimulates Cdc42 and Rac1. One of
the cellular targets of both Cdc42 and Rac1 that affects actin structure is the Arp2/3
complex. Cdc42 and Rac1 activate Wasp, which activates Arp2/3. Activated Arp2/3 induces
the formation of actin Y branches, which in combination with changes in actin caused
by SipA and SipC help to form lamellipodia, and causes membrane ruffling, leading
to entry of Salmonella into the affected cell. After the initial infection, cells
quickly return to their normal morphology, a process that depends on the action of
the bacterial protein SptP. While SopE acts as an exchange factor, SptP acts as a
GTPase activating protein to inactivate Rac1 and Cdc42 once again. This inactivation
of the original entry mechanism provides an example of the delicate balance between
infectious organisms and their host. (This definition may be outdated - see the DesignNote.);
NCIt note : The BIOCARTA Definition (ALT_DEFINITION) for this pathway concept was provided by
BioCarta. This property was not created by, nor is it maintained by the NCI Thesaurus
staff. Additionally, BioCarta is no longer updating its pathway data; thus, the BIOCARTA
Definition might be outdated or inaccurate. Please see the Terms and Conditions for
Use at http://www.biocarta.com/.;
Biocarta ID : h_salmonellaPathway;
Origin ID : C39227;
UMLS CUI : C1519178;
Semantic type(s)
has_gene_product_element
pathway_has_gene_element