Biophysical Society Thematic Meeting| Aussois 2019

Biology and Physics Confront Cell-Cell Adhesion

Poster Abstracts

2-POS Board 2 FUNCTION OF BLEBS IN CELL-CELL ADHESION STUDIED ON SUPPORTED LIPID BILAYERS Feyza Nur Arslan 1 ; Martin Loose 1 ; Carl-Philipp Heisenberg 1 ; 1 Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria Bleb-like protrusions are thought to contribute to locomotion of various cell types in development and disease. In zebrafish embryos, morphologically distinct blebs that travel around the cell periphery are commonly observed in intact as well as dissociated embryos, and have been implicated in progenitor cell migration. Yet, whether blebs have also other functions during the course of development, in particular in cell-cell adhesion, remains to be elucidated. Here, we have devised a biomimetic system consisting of supported lipid bilayers (SLBs) functionalized with zebrafish E-cadherin ectodomain (E-cad-ECD) as a cell-surface model. This system enables us to control bilayer composition and perform high spatiotemporal resolution imaging on cell- bilayer contacts of seeded zebrafish progenitor cells. We found that blebs frequently form and retract at the edge of cell-substrate contacts and trigger a temporary local enrichment of actin and E-cadherin at the contact edge during retraction. This local enrichment is followed by enhanced clustering and immobilization of E-cadherin at the contact, which again modulates contact growth. To determine the potential role of blebs in cell-cell contact formation, we are currently studying contact dynamics under conditions where we manipulate bleb formation by changing membrane-to-cortex attachment or actomyosin contractility.

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