IMEX   05356
INSTITUTO DE MEDICINA EXPERIMENTAL
Unidad Ejecutora - UE
artículos
Título:
Functional Capacity of Shiga-Toxin Promoter Sequences in Eukaryotic Cells
Autor/es:
BENTANCOR L.; BILEN M.F.; MEJIAS M.P.; FERNANDEZ-BRANDO R.J; PANEK C.A; RAMOS M.V; FERNANDEZ G.C.; ISTURIZ M.A; GHIRINGHELLI D.; PALERMO M.S
Revista:
PLOS ONE
Editorial:
PUBLIC LIBRARY SCIENCE
Referencias:
Lugar: San Francisco; Año: 2013 vol. 8 p. 1 - 14
ISSN:
1932-6203
Resumen:
Shiga toxins (Stx) are the main virulence factors in enterohemorrhagic Escherichia coli (EHEC) infections, causing diarrhea and hemolytic uremic syndrome (HUS). The genes encoding for Shiga toxin-2 (Stx2) are located in a bacteriophage. The toxin is formed by a single A subunit and five B subunits, each of which has its own promoter sequence. We have previously reported the expression of the B subunit within the eukaryotic environment, probably driven by their own promoter. The aim of this work was to evaluate the ability of the eukaryotic machinery to recognize stx2 sequences as eukaryotic-like promoters. Vero cells were transfected with a plasmid encoding Stx2 under its own promoter. The cytotoxic effect on these cells was similar to that observed upon incubation with purified Stx2. In addition, we showed that Stx2 expression in Stx2- insensitive BHK eukaryotic cells induced drastic morphological and cytoskeletal changes. In order to directly evaluate the capacity of the wild promoter sequences of the A and B subunits to drive protein expression in mammalian cells, GFP was cloned under eukaryotic-like putative promoter sequences. GFP expression was observed in 293T cells transfected with these constructions. These results show a novel and alternative way to synthesize Stx2 that could contribute to the global understanding of EHEC infections with immediate impact on the development of treatments or vaccines against HUS.