title: Recombinant Yersinia YopT leads to uncoupling of RhoA-effector interaction.
abstract: Yersinia enterocolitica, Yersinia pseudotuberculosis, and Yersinia pestis deliver different Yop (Yersinia outer proteins) effector proteins into mammalian cells by a type III secretion mechanism. Recently, it was shown that Yersinia producing YopT leads to disruption of the actin cytoskeleton of HeLa cells (M. Iriarte and G. R. Cornelis, Mol. Microbiol. 29:915-929, 1998). To analyze the molecular mechanism of YopT, we cloned and expressed YopT as a glutathione S-transferase fusion protein. Recombinant YopT caused rounding up of embryonic bovine lung cells and redistribution of the actin cytoskeleton rapidly after microinjection. The Escherichia coli cytotoxic necrotizing factor (CNF1), which constitutively activates Rho proteins, was not able to inhibit or revert YopT-induced cell rounding. YopT caused release of RhoA from embryonic bovine lung membranes and released recombinant isoprenylated RhoA from artificial PE or PE/PIP2 vesicles. Incubation of lysate or cytosol with YopT caused inhibition of the RhoA-rhotekin interaction but led to increased RhoA-RhoGDI interaction. It is suggested that inhibition of the interaction between RhoA and effectors is the underlying mechanism of the YopT action on the cytoskeleton.
authors.affiliation: Institut für Experimentelle und Klinische Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, D-79104 Freiburg, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Sorg
authors.forename: U M
authors.initials: UM
authors.lastname: Goehring
authors.forename: K
authors.initials: K
authors.lastname: Aktories
authors.forename: G
authors.initials: G
authors.lastname: Schmidt
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000494:pharmacology*; D001427:Bacterial Toxins; D002352:Carrier Proteins / Q000378:metabolism; D002417:Cattle; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases; D003600:Cytosol / Q000187:drug effects; D003603:Cytotoxins / Q000235:genetics / Q000494:pharmacology*; D029968:Escherichia coli Proteins; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D008168:Lung / Q000166:cytology; D008845:Microinjections; D008969:Molecular Sequence Data; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D015008:Yersinia enterocolitica / Q000235:genetics / Q000472:pathogenicity*; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; D020742:rhoA GTP-Binding Protein / Q000187:drug effects* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D002352:Carrier Proteins; D003603:Cytotoxins; D029968:Escherichia coli Proteins; D020730:Guanine Nucleotide Dissociation Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; C116117:YopT protein, Yersinia; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; C060296:cytotoxic necrotizing factor type 1; D003546:Cysteine Endopeptidases; D020742:rhoA GTP-Binding Protein