Histones: metabolism in simian virus 40-infected cells and incorporation into virions.

The infection of confluent monkey cells with simian virus 40 induced the synthesis of both cellular DNA and histones. However, during the course of infection, cellular histone synthesis was uncoupled from cellular DNA replication and became coupled to viral DNA replication. The synthesis of all five host histone species was induced after virus infection and they appeared to be more highly phosphorylated than their couterparts in uninfected cells. At late times after infection, the cells contained twice as much histones as did uninfected cells. All the histone species except H1 were incorporated into virions. Compared to cellular histones, virion histones were enriched in the arginine-rich species H3 and H4. Although both old and newly synthesized cellular histones were incorporated into virions, there were about 5 times more newly synthesized than old histone polypeptides in virions.