Conférence de l’Institut Jacques Monod – Gijsje Koenderink

Le 11 juillet, Gijsje Koenderink (Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology) présentera une conférence de l’Institut Jacques Monod sur le thème :

How cytoskeletal crosstalk makes cells strong

Résumé :

Our bodies are built up of cells and tissues with unique physical properties. Cells and tissues are dynamic but also need to withstand large mechanical loads. This paradoxical mechanical behavior is governed by fibrous protein scaffolds known as the cytoskeleton and the extracellular matrix. Fibrous networks have many advantageous mechanical properties: fibers can form space-filling elastic networks at low volume fractions and they reversibly stress-stiffen, which provides protection from damage. However, it is still poorly understood how biopolymer networks can combine these features with the ability to dynamically adapt their structure and mechanics. In this seminar I will focus on the cytoskeleton: how can the cytoskeleton combine mechanical strength with the ability to dynamically adapt its structure and mechanics? I will summarize our recent insights in this question obtained via quantitative measurements on living cells coupled with experiments on cell-free model systems. I will focus on the role of mechanical crosstalk between the actin, intermediate filament, and septin cytoskeletal networkds, three key determinants of cell mechanics. These three filamentous systems contribute different structural and dynamical properties, but their activities are closely coordinated. I will show that combining cell and cell-free assays allows us to dissect the collaborative and individual roles of the cytoskeletal systems. Our findings may eventually be interesting to guide the search for selective anticancer drugs, since cancer cells often overexpress specific intermediate filaments or septins leading to abnormal mechanical behaviors.