Microfilaments are required for the biogénesis of the Coxiella-replicative compartment

AGUILERA, M,; CARMINATI, S. ,; BERÓN, W

Pinamar, Buenos Aires

Congreso; XLI Reunión Nacional de la Sociedad Argentina de Investigaciones Bioquímica y Biología Molecular (SAIB), X Congreso de la Panamerican Association for Biochemistry and Molecular Biology, XX Reunión Anual de la Sociedad Argentina de Neuroquímica, Pinamar; 2005

Sociedad Argentina de Investigaciones Bioquímica y Biología Molecular (SAIB)

Q fiber is a disease caused by the intracellular pathogen Coxiella burnetii. This bacterium generates a large replicative compartment in the host cell, known as parasitophorous vacuole (PV). We have investigated the role of the actin cytoeskeleton in the biogenesis of the PV by using different agents. CHO cells were infected with C. burnetii Phase II for 16 hours and actin was visualized by fluorescence microscopy using phalloidin, at different times post infection. At early times after infection some small Coxiella-containing vacuoles were decorated by actin. However by 24-48 hs post infection there was a marked increase in the size of the PV and the colocalization with actin increased to 68-95%. Treatment of infected cells with the actin polymerization inhibitor latrunculin completely blocked PV formation. Interestingly, this inhibitory effect was reversed by washing out the drug and the large PV reformed after few hours. Similarly, PV generation was hampered by the miosin inhibitor butanodionemonoxime (BDM) although in an irreversible way. These results indicate that actin and miosin motors play a critical role in the biogenesis of the C. burnetii replicative niche.