title: Aeromonas salmonicida-secreted protein AopP is a potent inducer of apoptosis in a mammalian and a Drosophila model.
abstract: Some pathogens are able to establish themselves within the host because they have evolved mechanisms to disrupt host innate immunity. For example, a number of pathogens secrete preformed effector proteins via type III secretion apparatuses that influence innate immune or apoptotic signalling pathways. One group of effector proteins that usurp innate immune signalling is the YopJ-like family of bacterial effector proteins, which includes AopP from Aeromonas salmonicida. Aeromonas species are known to cause gastrointestinal disease in humans, and are associated mainly with subcutaneous wound infections and septicaemia in other metazoans, particularly fish. AopP has been reported to have inhibitory activity against the NF-κB pathway in cultured cells, although the pathological outcomes of AopP activity have not been examined. Here, we show that AopP has potent pro-apoptotic activity when expressed in cultured mammalian macrophage or epithelial cells, or when ectopically expressed in Drosophila melanogaster haemocytes or imaginal disk epithelial cells. Furthermore, apoptosis was significantly elevated upon concurrent AopP expression and TNF-α cellular stimulation. Together, our results demonstrate how the specificity of a YopJ-like protein towards signalling pathways directly governs cellular pathological outcome in disease.
authors: Departments of Pathology and Laboratory Medicine Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA. rjones5@emory.edu
authors: Rheinallt M
authors: RM
authors: Jones
authors: Liping
authors: L
authors: Luo
authors: Kenneth H
authors: KH
authors: Moberg
mesh_terms: D048409:Aeromonas salmonicida / Q000472:pathogenicity*; D000818:Animals; D017209:Apoptosis; D001426:Bacterial Proteins / Q000378:metabolism*; D002460:Cell Line; D002470:Cell Survival; D004331:Drosophila melanogaster; D004847:Epithelial Cells / Q000382:microbiology / Q000502:physiology; D006434:Hemocytes / Q000382:microbiology / Q000502:physiology; D006801:Humans; D007113:Immunity, Innate; D008264:Macrophages / Q000382:microbiology / Q000502:physiology; D016019:Survival Analysis; D037521:Virulence Factors / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D037521:Virulence Factors