PPOEEC · Physical Properties, Organization and Evolution of Eukaryotic Chromosomes

The remarkable structure and the key role hold by the DNA molecule in the living world raise numbers of fascinating questions with regard to its apparition and its evolution. However, little is known so far about the potential interplay between the physical status of chromosomes and their diverse biological functions. I aim at addressing these questions. As a postdoc I work at the interface of several disciplines, investigating physical properties of eukaryotic chromosomes as well as aspects of nuclear dynamic. In this regard, we recently proposed that variations in the chromatin compaction status could account for different types of chromosomal dynamics observed during meiotic prophase. In parallel to these studies, one of the primary goals of my research has been to achieve virtual trapping and manipulation of chromatin or individual chromosomes in a controlled environment. My objective is now to pursue the development of functional, user-friendly, devices in the host organization and develop long-term collaborations across EU member states with scientists from various disciplines. In addition to this in vitro approach, I propose to investigate further the organization of chromosomes/chromatin during replication, and their impact onto genome structure. Using the 3C/5C technology partially developed in my current laboratory, I will perform a genome – wide mapping of yeast replication factories to determine whether large intra or inter-chromosomal regions are coordinately replicated in the same replication factories or not. Furthermore, I propose to investigate whether some DNA regions involved in specific chromosomal rearrangements interact preferentially because of transient co-localization during replication within a same factory. This will provide a new understanding of the “contact-first” model for chromosome rearrangement and deepen our insight onto chromosome evolution, and cancer.