1. Actin dynamics and the Bmp pathway drive apical extrusion of proepicardial cells.
- Author
-
Andrés-Delgado L, Ernst A, Galardi-Castilla M, Bazaga D, Peralta M, Münch J, González-Rosa JM, Marques I, Tessadori F, de la Pompa JL, Vermot J, and Mercader N
- Subjects
- Animals, Animals, Genetically Modified, Body Patterning genetics, Carrier Proteins genetics, Carrier Proteins metabolism, Embryo, Nonmammalian, Myocardium cytology, Organogenesis genetics, Signal Transduction physiology, Stem Cells cytology, Zebrafish embryology, Zebrafish genetics, Zebrafish Proteins genetics, Zebrafish Proteins metabolism, Actins metabolism, Bone Morphogenetic Proteins metabolism, Cell Movement genetics, Heart embryology, Pericardium cytology, Pericardium embryology, Stem Cells physiology
- Abstract
The epicardium, the outer mesothelial layer enclosing the myocardium, plays key roles in heart development and regeneration. During embryogenesis, the epicardium arises from the proepicardium (PE), a cell cluster that appears in the dorsal pericardium (DP) close to the venous pole of the heart. Little is known about how the PE emerges from the pericardial mesothelium. Using a zebrafish model and a combination of genetic tools, pharmacological agents and quantitative in vivo imaging, we reveal that a coordinated collective movement of DP cells drives PE formation. We found that Bmp signaling and the actomyosin cytoskeleton promote constriction of the DP, which enables PE cells to extrude apically. We provide evidence that cell extrusion, which has been described in the elimination of unfit cells from epithelia and the emergence of hematopoietic stem cells, is also a mechanism for PE cells to exit an organized mesothelium and fulfil their developmental fate to form a new tissue layer, the epicardium., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2019. Published by The Company of Biologists Ltd.)
- Published
- 2019
- Full Text
- View/download PDF