A.1: Cellular Polarization and Changes in Cell Shape
Participants: Erez Raz, Ivan Bedzhov, Timo Betz, Karin Busch, Cornelia Denz, Carsten Fallnich, Xiaoyi Jiang, Christian Klämbt, Stefan Luschnig, Maja Matis, Wolfram Pernice, Andreas Püschel, Sebastian Rumpf, Britta Trappmann, Roland Wedlich-Söldner
Migration of cells requires the dynamic rearrangement of determinants of molecular and morphological polarization. Cell polarization and alterations in cell shape facilitate movement through tissues by allowing squeezing, dynamic alteration of contacts with the cellular and extracellular environment, and formation of stable interactions upon arrival at the target tissue. Work in this research area will focus on investigating cell polarization and the competence for directional motility in a variety of models including germ cell migration in zebrafish, glial cell migration in Drosophila and neural stem cell dynamics in the mouse brain. Cell shape and polarization markers will first be characterized under normal conditions using novel fluorescent markers and in vivo optical imaging (e.g. 2-photon microscopy, multimodal label-free non-linear microscopy). These measurements will be correlated with physical properties relevant for cell shape and polarization, such as membrane tension, cortex stiffness and cytoplasmic flow. Mathematical analysis of movies and snapshots of cells will be used to define the ‘average normal’ cell shape followed by identification of deviations from it in the different systems. Alterations in cell fate programming and the functional manipulation of candidate pathways within the migrating cells or in the environment will then be employed to unravel fundamental principles underlying the migratory event. This will shed light on the programmes translating genetic and epigenetic information into specific cell behaviour and will help to decipher the mechanisms underlying the acquisition of cellular polarity relevant for effective motility.