Biophysical Society Thematic Meeting| Les Houches 2019

Multiscale Modeling of Chromatin: Bridging Experiment with Theory

Tuesday Speaker Abstracts

CHROMATIN DYNAMICS GOVERNED BY A SET OF NUCLEAR STRUCTURAL PROTEINS Anat Galis Vivante 1 ; Irena Bronshtein 1 ; Yuval Garini 1 ; 1 Bar Ilan University, Physics Department & Nanotechnology Institute, Ramat Gan, Center, Israel In eukaryotic cells, tens of thousands of genes are packed in the small volume of the nucleus. The genome itself is organized in chromosomes that occupy specific volumes referred to as chromosome territories. This organization is preserved throughout the cell cycle, even though there are no sub-compartments in the nucleus itself. The nuclear structure is strongly related to the dynamic properties. Hence, the dynamics of the nucleus content is fundamental for understanding its appropriate function. The organization and dynamics of chromatin are directly responsible for many functions including gene regulation, genome replication, and maintenance. In order to better understand the details of these mechanisms, we need to understand the role of specific proteins that take part in these processes. We use live imaging methods to characterize the dynamic properties of the chromatin and its organization in living cells. More specifically, we use single particle tracking of different genomic regions, and implement Continuous Photobleaching (CP) measurements which provide crucial information on the mobility and binding properties of the proteins. Through these methods, we studied lamin A, BAF, Emerin, lamin B, CTCF, and Cohesin and analyze their effect on chromatin dynamics. Finally, we suggest a model of chromatin organization and develop a new type of diagram for mapping and analyzing the regulating networks of chromatin organization.

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