Page 58 - Hormel Report 2023

Chuanhe Yu, PhD
“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
58 | THE HORMEL INSTITUTE // Inheritance of
Epigenetic Information
ASSISTANT PROFESSOR
UNIVERSITY OF MINNESOTA
DNA replication accurately copies the genetic information from one generation to the next, while the epigenetic information
carried by the histone proteins must be inherited to maintain stable gene expression. On the newly synthesized DNA, half of the histones are from the parental chromatin. The mechanism of recycling parental histone H3-H4 is not clear.
To study this, we designed a high throughput sequencing-based method named eSPAN (enrichment and sequencing of protein-associ- ated nascent DNA) method which enables us to
detect the targeted protein such as histones or histone marks on the replication leading and lagging strands. With this new tool, we first observed that DNA replication helicase subunit Mcm2 (minichromosome maintenance subunit 2) and DNA polymerase epsilon subunits Dpb3/ Dpb4 facilitate the transfer of parental histones to DNA leading strands and lagging strands, respectively. Our genetic and biochemical analyses showed that the homologous-based recombination frequency was significantly decreased in the Mcm2 mutant (mcm2-3A),