Conference of the Fédération de Recherche en Biologie de Toulouse (FRBT)
Institute for Integrative Biology of the Cell - Department of Genome Biology
UMR 9198 - CEA/CNRS/Université Paris Sud
Postmitotic nuclear assembly: Role of human telomere tethering to the nuclear envelope for the reformation of a functional G1 nucleus
The spatial and temporal organization of the nucleus and its components is essential for genome regulation. During interphase of mammalian cells the nuclear envelope maintains the shape and the mechanical integrity of the nucleus, but also provides an anchor for chromatin that is connected to its inner side. This interaction mediates the regulation of gene expression, DNA replication and the maintenance of genome stability. In human cells a large subset of telomeres, the natural ends of linear chromosomes, are transiently anchored to the nuclear envelope specifically during postmitotic nuclear assembly . Chromatin
organization undergoes extensive changes during progression through the cell cycle, particularly during mitosis with the nuclear envelope breakdown and the compaction of chromatin into metaphase chromosomes. The interaction between chromosome ends and the nuclear envelope at the stage where the nucleus is reforming post-mitosis suggests a new role for telomeres in nuclear organization.
In this talk I will present the research projects that we are conducting in my newly established lab (ATIP-Avenir 2015 – ERC StG 2017). We first aim at deciphering the molecular mechanisms of telomere tethering to nuclear envelope in human cells in a cell cycledependent manner. Our second goal is to discover the biological significance of telomere attachment to the nuclear periphery for nuclear organization and regulation of cell division. A special emphasis is put on the unregulated growth of cancer cells and during normal or accelerated aging. Finally, we are also analyzing telomere dynamics in the context of unprotected telomeres, whether it is spontaneous or induced.
1. Crabbe L, Cesare AJ, Kasuboski JM, Fitzpatrick JAJ, Karlseder J. Human telomeres are
tethered to the nuclear envelope during postmitotic nuclear assembly. Cell Rep (2012) 2:1521–9
Contact: Jean-Philippe Girard (firstname.lastname@example.org) & Didier Trouche (email@example.com)
14:00 - 15:00
CBI - IBCG Seminar room