title: Abl suppresses cell extrusion and intercalation during epithelium folding.
abstract: Tissue morphogenesis requires control over cell shape changes and rearrangements. In the Drosophila mesoderm, linked epithelial cells apically constrict, without cell extrusion or intercalation, to fold the epithelium into a tube that will then undergo epithelial-to-mesenchymal transition (EMT). Apical constriction drives tissue folding or cell extrusion in different contexts, but the mechanisms that dictate the specific outcomes are poorly understood. Using live imaging, we found that Abelson (Abl) tyrosine kinase depletion causes apically constricting cells to undergo aberrant basal cell extrusion and cell intercalation. abl depletion disrupted apical-basal polarity and adherens junction organization in mesoderm cells, suggesting that extruding cells undergo premature EMT. The polarity loss was associated with abnormal basolateral contractile actomyosin and Enabled (Ena) accumulation. Depletion of the Abl effector Enabled (Ena) in abl-depleted embryos suppressed the abl phenotype, consistent with cell extrusion resulting from misregulated ena Our work provides new insight into how Abl loss and Ena misregulation promote cell extrusion and EMT.
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
authors.forename: Jeanne N
authors.initials: JN
authors.lastname: Jodoin
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142 acmartin@mit.edu.
authors.forename: Adam C
authors.initials: AC
authors.lastname: Martin
mesh_terms: D000199:Actins / Q000378:metabolism; D000205:Actomyosin / Q000378:metabolism; D022005:Adherens Junctions; D000818:Animals; D016764:Cell Polarity / Q000502:physiology; D048430:Cell Shape; D004268:DNA-Binding Proteins / Q000378:metabolism; D004330:Drosophila / Q000254:growth & development / Q000378:metabolism; D029721:Drosophila Proteins / Q000378:metabolism* / Q000502:physiology*; D004331:Drosophila melanogaster / Q000254:growth & development / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology; D004848:Epithelium / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D009024:Morphogenesis / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000378:metabolism* / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D000199:Actins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C092744:ENA-VASP proteins; D000205:Actomyosin; D011505:Protein-Tyrosine Kinases; C506548:Abl protein, Drosophila