Microtubules and dynein are required for formation of Coxiella burnetii-containing vacuoles

AGUILERA MO, ROSALES EM, SALINAS RP, CARMINATI S, HEINZEN R AND BERÓN W

Tucuman

Congreso; XLV Reunión Nacional de la Sociedad Argentina de Investigaciones Bioquímica y Biología Molecular; 2009

Sociedad Argentina de Investigaciones Bioquímica y Biología Molecular

Coxiella burnetii (Cb) is an intracellular pathogen that causes Q fever disease. Cb replicates within a big vacuole called parasitophorous vacuole (PV), which interacts with vesicles from the endocytic and phagocytic pathways. Microtubules (Mt) and Mt motor proteins such as dynein and kinesin are the key components in vesicular trafficking. We analyzed if Mt, dynein and kinesin are involved in PV formation. We tested the effect of nocodazole (Noc), an inhibitor of Mt polymerization, on PV formation. HeLa cells were incubated by 2 h with Cb, then treated for 46 h with DMSO or Noc, fixed and processed for indirect immunofluorescence. Then, the cells were analyzed by confocal microscopy. Interestingly, Noc inhibited PV formation. Furthermore, we also analyzed the interaction between PV and endocytic compartments in Noc-treated cells. We observed a decrease in the colocalization between Cb and dextran-texas red (endocytic marker) and also between Cb and CD63 (lysosomal marker). Then, we analyzed the effect of EHNA, a specific dynein inhibitor, or ATA, a specific kinesin inhibitor. HeLa cells were treated as mention above. EHNA but not ATA inhibited PV formation. Also, like Noc treatment, EHNA diminished the colacalization of Cb with dextran-texas red and with CD63. We could conclude that Mt and dynein are involved in both PV formation and interaction of PV with endocytic compartments.