TY - JOUR T1 - Apical contacts stemming from incomplete delamination guide progenitor cell allocation through a dragging mechanism JF - bioRxiv DO - 10.1101/2021.02.24.432660 SP - 2021.02.24.432660 AU - Eduardo Pulgar AU - Cornelia Schwayer AU - Néstor Guerrero AU - Loreto López AU - Susana Márquez AU - Steffen Härtel AU - Rodrigo Soto AU - Carl-Philipp Heisenberg AU - Miguel L. Concha Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/02/25/2021.02.24.432660.abstract N2 - The developmental strategies used by progenitor cells to endure a safe journey from their induction place towards the site of terminal differentiation are still poorly understood. Here we uncovered a progenitor cell allocation mechanism that stems from an incomplete process of epithelial delamination that allows progenitors to coordinate their movement with adjacent extra-embryonic tissues. Progenitors of the zebrafish laterality organ originate from the surface epithelial enveloping layer by an apical constriction process of cell delamination. During this process, progenitors retain long-term apical contacts that enable the epithelial layer to pull a subset of progenitors along their way towards the vegetal pole. The remaining delaminated progenitors follow apically-attached progenitors’ movement by a co-attraction mechanism, avoiding sequestration by the adjacent endoderm, ensuring their fate and collective allocation at the differentiation site. Thus, we reveal that incomplete delamination serves as a cellular platform for coordinated tissue movements during development.Impact Statement Incomplete delamination serves as a cellular platform for coordinated tissue movements during development, guiding newly formed progenitor cell groups to the differentiation site. ER -