Abstract
Time-lapse live imaging fluorescence confocal microscopy was used to describe the dynamics of mouse polyomavirus (MPyV) trafficking in host cells. Twenty minutes post infection, relatively static virions (in vesicles) were observed associated with actin filaments.
Some virion-loaded vesicles were seen to move with actin organised into dynamic structures. Fast bi-directional movement of the virus along microtubules was also observed.
Disruption of microtubular network by drug treatment reversibly abolished virus infectivity. In the presence of actin destroying agents (latrunculin A, cytochalasin D), infectivity of the virus was markedly enhanced.
In the presence of actin stabilizing drugs (jasplakinolide), only slight decrease of infectivity was observed, suggesting that dynamic actin is not indispensable for productive infection. These results suggest that while intact tubulin is essential for productive infection, actin may rather play a role in host cell defence