We have measured the activation of the small GTPase Ral in human neutrophils after stimulation with fMet-Leu-Phe (fMLP), platelet activating factor (PAF), and granulocyte macrophage-colony stimulating factor and compared it with the activation of two other small GTPases, Ras and Rap1. We found that fMLP and PAF, but not granulocyte macrophage-colony stimulating factor, induce Ral activation. Al...

Human intestinal cells lack globotriaosylceramide (Gb(3)), the receptor for Shiga toxin-1 (Stx1) and Shiga toxin-2 (Stx2). Therefore, the role of these toxins in mediating intestinal disease during infection with Shiga toxin-producing Escherichia coli is unclear. The aims of this study were to determine whether Stx1 and Stx2 induce apoptosis in epithelial cells expressing (HEp-2, Caco-2) or lac...

The mammalian retromer complex is a multi-protein complex that regulates retrograde transport of the cation-independent mannose 6-phosphate receptor (CI-MPR) from early endosomes to the trans Golgi network (TGN). It consists of two subcomplexes: a membrane-bound coat comprising sorting nexin-1 (SNX1) and possibly sorting nexin-2 (SNX2), and a cargo-selective subcomplex, composed of VPS26, VPS29...

Retrograde transport links early/recycling endosomes to the trans-Golgi network (TGN), thereby connecting the endocytic and the biosynthetic/secretory pathways. To determine how internalized molecules are targeted to the retrograde route, we have interfered with the function of clathrin and that of two proteins that interact with it, AP1 and epsinR. We found that the glycosphingolipid binding b...

The retrograde transport route links early endosomes and the TGN. Several endogenous and exogenous cargo proteins use this pathway, one of which is the well-explored bacterial Shiga toxin. ADP-ribosylation factors (Arfs) are approximately 20 kDa GTP-binding proteins that are required for protein traffic at the level of the Golgi complex and early endosomes. In this study, we expressed mutants a...

A. Agent Hemolytic uremic syndrome (HUS) is a syndrome of anemia, renal failure and low platelet count, for which there are several causes. Among children, the most common cause of HUS is infection with a Shiga toxin-producing organism, most commonly Escherichia coli O157:H7 or some other strain of enterohemorrhagic E. coli (EHEC). Shigella dysenteriae also produces Shiga toxin and HUS can also...

Shiga toxins (Stxs) induce apoptosis via activation of the intrinsic and extrinsic pathways in many cell types. Toxin-mediated activation of the endoplasmic reticulum (ER) stress response was shown to be instrumental in initiating apoptosis in THP-1 myeloid leukemia cells. THP-1 cells responded to Shiga toxin type 1 (Stx1) in a cell maturation-dependent manner, undergoing rapid apoptosis in the...

novel subtype of Shiga Toxin type 1 2 Authors: William S. Probert, Cassandra McQuaid, and Kimmi Schrader 3 Affiliation: Microbial Diseases Laboratory Branch, California Department of Public 4 Health, Richmond, CA 5 Running Header: Shiga toxin-producing Enterobacter cloacae 6 Address Correspondence to William S. Probert, [email protected] 7 *Present Address: Cassandra McQuaid, San Francis...