Early events in the eclipse phase of influenza and parainfluenza virus infection

Abstract

The role of the cell nucleus in the multiplication of influenza and parainfluenza viruses has been examined. While the capacity of cells to support the growth of para-influenza virus is relatively resistant to preirradiation with ultraviolet light, their capacity to support the growth of influenza virus is just as sensitive as the cell-virus complex shortly after infection. Between 1 2 and 2 1 2 hours post-infection the cell-virus complex acquires resistance to irradiation. The findings indicate that cell-coded messenger RNA is required in the early stages of influenza virus multiplication, but plays no role in the replication of viral nucleic acid or any subsequent event. Multiplicity-dependent delay in the multiplication of influenza virus takes place after the synthesis of at least one “early” protein but before the latest point of action of actinomycin D, before the acquisition of resistance to ultraviolet irradiation and before the establishment of interference.