The Journal of Cell Biology, Vol 90, 415-417, Copyright © 1981 by The Rockefeller University Press
Asynchronous appearance of newly synthesized histone H1 subfractions in HeLa chromatin
SR Sizemore and RD Cole
Incorporation of radioactive alanine into chromatin-bound subfractions of
H1 histone was studied in HeLa cells synchronized by the double thymidine
block technique. The subfractions were resolved into three chromatographic
peaks by Biorex-70. In the period 5-7 h after release from the thymidine
block, peaks I and III showed twice as much incorporation as they did in
the period 1-3 h after release, whereas peak II showed three times the
incorporation at 5-7 h that it did at 1- 3 h. Thus, the H1-histone
subfraction in peak II appears in chromatin somewhat later in S phase than
do the subfractions in Peaks I and III.