title: The actin cable is dispensable in directing dorsal closure dynamics but neutralizes mechanical stress to prevent scarring in the Drosophila embryo.
abstract: The actin cable is a supracellular structure that embryonic epithelia produce to close gaps. However, the action of the cable remains debated. Here, we address the function of the cable using Drosophila dorsal closure, a paradigm to understand wound healing. First, we show that the actin cytoskeleton protein Zasp52 is specifically required for actin cable formation. Next, we used Zasp52 loss of function to dissect the mechanism of action of the cable. Surprisingly, closure dynamics are perfect in Zasp52 mutants: the cable is therefore dispensable for closure, even in the absence of the amnioserosa. Conversely, we observed that the cable protects cellular geometries from robust morphogenetic forces that otherwise interfere with closure: the absence of cable results in defects in epithelial organization that lead to morphogenetic scarring. We propose that the cable prevents morphogenetic scarring by stabilizing cellular interactions rather than by acting on closure dynamics.
authors.affiliation: LBMC, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, SFR 128 Biosciences Lyon Gerland, Université de Lyon, 69007 Lyon, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Ducuing
authors.affiliation: LBMC, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, SFR 128 Biosciences Lyon Gerland, Université de Lyon, 69007 Lyon, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Vincent
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism*; D000199:Actins / Q000378:metabolism*; D000818:Animals; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000196:embryology / Q000378:metabolism*; D047108:Embryonic Development / Q000502:physiology*; D000078404:Epidermal Cells; D004848:Epithelium / Q000378:metabolism* / Q000473:pathology; D013314:Stress, Mechanical; D014945:Wound Healing / Q000502:physiology*
chemical_list: D000199:Actins; D029721:Drosophila Proteins