ZBP-Kolloquium

Prof. Dr. Jörg Renkawitz (LMU München)
Title: Centrosome integrity controls microtubule network architecture and cellular pathfinding
Time: 14:15 (refreshments at 14:00)
Location: Campus SB, Building C6 4, room 0.09 (Hörsaal II), Click here to join via Teams
Host: Prof. Franziska Lautenschläger

Abstract: The centrosome orchestrates the microtubule network by nucleating and anchoring radial microtubule arrays that coordinate intracellular transport. At the same time, mechanical stresses from the microenvironment and changes in cellular shape compress and bend microtubules, raising the question of how the membrane-less centrosome withstands mechanical forces.

In recent work (Schmitt et al., Science Advances, 2025), we discovered that migration through confining three-dimensional microenvironments mechanically deforms the centrosome, rendering it susceptible to breakage. We identify a protective pathway in which the kinase Dyrk3 cooperates with the centrosomal linker protein cNAP1 to preserve centrosome cohesion and resist actomyosin force-induced fragmentation.

Centrosome fracturing leads to spatially separated, coexisting microtubule-organizing centers (MTOCs), thereby generating competing microtubule networks within a single cell. Live-cell imaging of competing MTOCs upon centrosome fracture demonstrates delayed path decisions during cell migration, leading to the entanglement of rapidly migrating immune cells and slow-migrating fibroblasts in three-dimensional microenvironments. In contrast, cells lacking centrioles but maintaining a single functional MTOC retain efficient directional decision-making. Thus, it is not centriole loss, but the coexistence of multiple functional MTOCs that impairs efficient cell migration. These results establish that it is critical for motile cells to maintain their microtubule architecture from a single microtubule-organising centre. More broadly, our findings demonstrate the importance of microtubule-based architecture in highly dynamic cells with complex shapes.

Further, I will present new findings demonstrating how the spatiotemporal dynamics of the microtubule network architecture are critical for cell migration in complex three-dimensional microenvironments. 

If you are interested in an individual meeting with the speaker, please contact the respective host or Philipp Hövel (philipp.hoevel@uni-saarland.de).