Séminaire de Mathématique-Biologie

Topological Investigations of Bacterial Site-Specific Recombination, Genome Differentiation in Ciliates and Kinetoplast DNA in Trypanosomes

by Prof. Karin VALENCIA (IHÉS)

Amphithéâtre Léon Motchane (IHES)

Amphithéâtre Léon Motchane


Le Bois-Marie 35, route de Chartres 91440 Bures-sur-Yvette
Since the double helical structure of DNA was discovered in 1953, decades of research into the behaviour of DNA have revealed many other fascinating phenomena about of the molecule of life. In 1965, Jerome Vinograd discovered that DNA in the polyoma virus is naturally found in a circular form. This work opened the gates to a new interdisciplinary field that studies the topology of DNA and its biological implications for the functionality of the molecule. In this talk I will introduce topological aspects of (i) bacterial site-specific recombination – an important cellular reaction that exchanges segments of DNA and is capable of creating (topological) knots and links; (ii) developmental genome rearrangements in ciliates – organisms whose genome, during specialisation, has a complex spatial structure that can be measured by the genus; and (iii) the organisation of the kinetoplast DNA in trypanosomes – whose kinetoplast genome (the `energy power-house' of the cell) consists of thousands of DNA circles that are chained to each other, forming a non-trivial link that resembles a medieval mailchain armour.