Nucleosome assembly during DNA replication

Published on April 30, 2009 Reviewed on December 4, 2019   35 min

A selection of talks on Cell Biology

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My name is Alain Verreault, and I'm an associate professor in the Department of Pathology and Cell Biology at the University of Montreal. And my group studies nucleosome assembly during DNA replication at the Institute for Research in Immunology and Cancer.
The aim of this lecture is to describe the process of nucleosome assembly coupled to DNA replication. I also intend to explain some of the physiological and biomedical implications of this important but poorly understood pathway. Whenever appropriate, references to original papers or reviews are indicated at the bottom of each slide. I've divided this lecture into four sections. First, I'll describe the generic structure of chromatin. In the second part, I will present an overview of chromatin rearrangements that occur during S-phase of the cell cycle. The third portion of my presentation will focus on the replication-coupled nucleosome assembly. And the final segment of the lecture will describe some of the biomedical implications of replication-coupled nucleosome assembly.
The primary function of histones in chromatin is to package DNA within the cell nucleus. The sheer magnitude of DNA compaction that is necessary to package human DNA can be illustrated with a few telling numbers. Each cell in the human body contains a total length of about 2 meters of DNA that is confined within a cell nucleus whose diameter is only about 10 micrometers. A simple calculation reveals that the total length of DNA in an average-sized human body is equivalent to a staggering 1,500 round trips from the Earth to the sun. The obvious challenge is to package this enormous amount of DNA in a form that allows regulated access to genetic information whenever necessary.