Induction of an Arginine-rich Component during Infection with Influenza Virus

Summary Secondary chick embryo fibroblasts infected with fowl plague virus were pulsed with [3H]arginine and treated with ethanol and hydrochloric acid. Radioautographic pictures disclosed heavily labelled nuclei in infected cells; uninfected controls had an even distribution of grains over nucleus and cytoplasm. Total incorporation into infected cells was about three times that in controls during the whole productive cycle. Quantitative comparison of the number of grains over nucleus and cytoplasm indicated that the nucleus was the site of synthesis of this arginine-rich component. With [3H]leucine and [3H]lysine additional nuclear incorporation was very weak or could not be seen.