Involvement of the cytoskeleton in Junin virus multiplication

The role of the cellular cytoskeleton in Junin virus (JV) infection was exp lored in two ways, Firstly, the action of inhibitors that affect individual cytoskeletal systems (microtubules or microfilaments) selectively was anal ysed. It was found that perturbations of microtubule or microfilament netwo rks caused by colchicine, nocodazole, nifedipine, EGTA or DMSO strongly aff ected virion production and viral protein expression at non-cytotoxic conce ntrations. Secondly, the extent of association of viral proteins and infect ious virus particles with the cytoskeletal fraction of monkey Vero cells wa s determined by using three non-ionic detergents, Triton X-100 (TX-100), NP -40 and octyl glucoside (OG). The cytoskeleton retained nearly 70% of the e xternal JV envelope glycoprotein GP38 and about 40% of the JV nucleoprotein NP, according to TX-100 and OG insolubility results. Furthermore, 1% of th e total cell-bound infectivity was detected in the detergent-insoluble frac tion, suggesting that cytoskeletal components are involved in the initiatio n of the assembly and budding processes of JV particles at the plasma membr ane.