Page 56 - Hormel Report 2021
P. 56
Chuanhe Yu, Ph.D.
“Chromatin, which contains both genetic and epigenetic information, must be stably transmitted to daughter cells during mitotic cell divisions to maintain genome integrity
and cell identity.”
Chuanhe Yu
56 | THE HORMEL INSTITUTE // Inheritance of
Epigenetic Information
SECTION LEADER / ASSISTANT PROFESSOR
UNIVERSITY OF MINNESOTA
We find that parental histones are distrib- uted to both the leading and lagging strand arm of the fork with a slight
bias towards the lagging strand. Intriguingly,
in cells depleted of Dpb3 and Dpb4, which are non-catalytic subunits of the leading strand DNA polymerase, Pol-epsilon, the bias of parental nucleosome segregation to the lagging strand was markedly enhanced. Pol-epsilon thus appears to mediate the recruitment of parental nucleosomes to the leading strand.
Mutation of the histone H3-H4 binding domain
in the Mcm2 subunit of the replicative helicase causes a strong bias of parental nucleosome partitioning to the leading strand, indicating that Mcm2 targets parental nucleosomes for depo- sition on the lagging strand. that parental H3-H4 tetramers bind to Mcm2, which travels along the leading-strand template, and are then transferred to the lagging strand by the Mcm2-Ctf4-Pola complex for nucleosome assembly.
