Histone proteins in HeLa S3 cells are synthesized in a cell cycle stage specific manner.

The synthesis of histone proteins in G1 and S phase HeLa S3 cells was examined by two-dimensional electrophoretic fractionation of nuclear and total cellular proteins. Newly synthesized histones were detected only in S phase cells. Histone messenger RNA sequences, as detected by hybridization with cloned human histone genes, were present in the cytoplasm of S phase but not G1 cells.