THE CYTOPLASMIC SYNTHESIS OF HISTONES IN HELA CELLS AND ITS TEMPORAL RELATIONSHIP TO DNA REPLICATION

Abstract

In synchronized HeLa cells there is a precise correlation between the initiation of histone and DNA synthesis. Pulse-chase labeling of cells in G1 and S and examination of cytoplasmic polysomes doubly labeled with tryptophan and lyslne have shown that hlstones are made in cytoplasm on small polysomes. The DNA inhibitors cytosine arabinoslde and 5 fluorodeoxyurldlne cause the selective disruption of these when they are added during S, but have no effect on small polysomes of the same size when added during G1.