title: Proteomic insight into the effects of the Salmonella ubiquitin ligase SlrP on host cells.
abstract: The virulence of the human and animal pathogen Salmonella enterica serovar Typhimurium is dependent on two type III secretion systems. These systems translocate proteins called effectors into eukaryotic host cells. SlrP is a Salmonella type III secretion effector with ubiquitin ligase activity. Here, we used two complementary proteomic approaches, two-dimensional gel electrophoresis and iTRAQ (isobaric tags for relative and absolute quantification) to study the consequences of the presence of SlrP in human epithelial cells. We identified 37 proteins that were differentially expressed in HeLa cells expressing slrP compared to control cells. Microarray analysis revealed that more than a half of differentially expressed proteins did not show changes in the transcriptome, suggesting post-transcriptional regulation. A gene ontology overrepresentation test carried out on the differentially expressed proteins revealed enrichment of ontology terms related to several types of junctions mediating adhesion in epithelial cells. Consistently, slrP-transfected cells showed defects in migration and adhesion. Our results suggest that the modification of cell-cell interaction ability of the host could be one of the final consequences of the action of SlrP during an infection.
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain. Electronic address: mmcordero@cnb.csic.es.
authors.forename: Mar
authors.initials: M
authors.lastname: Cordero-Alba
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain. Electronic address: jjgarcia@us.es.
authors.forename: Juan José
authors.initials: JJ
authors.lastname: García-Gómez
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain. Electronic address: jaguilera3@us.es.
authors.forename: Julia
authors.initials: J
authors.lastname: Aguilera-Herce
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain. Electronic address: framos@us.es.
authors.forename: Francisco
authors.initials: F
authors.lastname: Ramos-Morales
mesh_terms: D001426:Bacterial Proteins / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology*; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology; D006367:HeLa Cells; D054884:Host-Pathogen Interactions / Q000502:physiology*; D006801:Humans; D020543:Proteome / Q000378:metabolism*; D012475:Salmonella / Q000201:enzymology; D037521:Virulence Factors / Q000494:pharmacology*
chemical_list: D001426:Bacterial Proteins; D020543:Proteome; C401846:SlrP protein, Salmonella typhimurium; D037521:Virulence Factors
keywords: Cell adhesion; Salmonella; SlrP; Type III secretion; iTRAQ