Phosphorylation of a ribosomal protein in invertebrate cells infected with ultraviolet-inactivated iridovirus type 6

Abstract

Summary Chilo iridescent virus (CIV) infection induces a rapid shut-off of macromolecular synthesis in insect host cells. We have previously shown that CIV infection induced the appearance of new phosphoproteins in permissive cells of Choristoneura fumiferana (Cf-124) [15]. Among them, phosphorylation of a 31 Kd ribosomal protein (very similar to the S6 protein) was observed 3 h after infection of Cf-124 cells with UV-inactivated CIV. However, such phosphorylation could not be detected in cells infected native CIV in the same conditions. As previously postulated [15], these results could be interpreted either as an absence of phosphorylation of this ribosomal protein, or as a dephosphorylation step occurring very rapidly during the early stages of the replication cycle, in cells infected with native CIV, as reported for the infection of BHK21 cells by vaccinia virus [1].