MODIFICATION OF CYTOSKELETON AND PROSOME NETWORKS IN RELATION TO PROTEIN-SYNTHESIS IN INFLUENZA-A VIRUS-INFECTED LLC-MK2 CELLS

Modifications of the cytoskeleton and protein synthesis were investiga ted in LLC-MK2 cells during infection by FPV/Ulster 73, an avian strai n of influenza A virus. During infection, the cytoskeleton and the pro some networks undergo a dramatic reorganization, which seems to be at least temporally differentiated for each cytoskeletal system, i.e. mic rofilaments (MFs), microtubules (MTs), intermediate filaments (IFs). I n order to evaluate the role of the three different cytoskeletal netwo rks during FPV/Ulster infection, studies were carried out on cellular and virus-specific protein synthesis and viral production, using drugs which selectively affect individual cytoskeletal systems. Our data sh ow that the perturbation of the IF system, but not that of the MFs or MTs, seems to have a strong inhibitory effect on virus production and cellular and viral protein synthesis. Furthermore, the dynamics of IFs and prosomes were investigated during viral infection and, at no time , dissociation of the prosome and IF networks was observed. Taken toge ther, these results strongly support the idea that the interactions be tween the protein synthesis machinery, the cytoskeleton, and the proso mes are all affected by viral infection in a partially coordinated man ner. (C) 1997 Elsevier Science B.V.