title: Drosophilanon-muscle myosin II motor activity determines the rate of tissue folding.
abstract: Non-muscle cell contractility is critical for tissues to adopt shape changes. Although, the non-muscle myosin II holoenzyme (myosin) is a molecular motor that powers contraction of actin cytoskeleton networks, recent studies have questioned the importance of myosin motor activity cell and tissue shape changes. Here, combining the biochemical analysis of enzymatic and motile properties for purified myosin mutants with in vivo measurements of apical constriction for the same mutants, we show that in vivo constriction rate scales with myosin motor activity. We show that so-called phosphomimetic mutants of theDrosophilaregulatory light chain (RLC) do not mimic the phosphorylated RLC state in vitro. The defect in the myosin motor activity in these mutants is evident in developingDrosophilaembryos where tissue recoil following laser ablation is decreased compared to wild-type tissue. Overall, our data highlights that myosin activity is required for rapid cell contraction and tissue folding in developingDrosophilaembryos.
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.
authors.forename: Claudia G
authors.initials: CG
authors.lastname: Vasquez
authors.affiliation: Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Heissler
authors.affiliation: Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States.
authors.forename: Neil
authors.initials: N
authors.lastname: Billington
authors.affiliation: Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States.
authors.forename: James R
authors.initials: JR
authors.lastname: Sellers
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.
authors.forename: Adam C
authors.identifier: 0000-0001-8060-2607
authors.initials: AC
authors.lastname: Martin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D004625:Embryo, Nonmammalian; D015870:Gene Expression; D006801:Humans; D007700:Kinetics; D051379:Mice; D009024:Morphogenesis / Q000235:genetics; D009038:Motion; D018994:Myosin Light Chains / Q000235:genetics* / Q000378:metabolism; D015879:Myosin Subfragments / Q000235:genetics* / Q000378:metabolism; D024507:Nonmuscle Myosin Type IIA / Q000235:genetics* / Q000378:metabolism; D010766:Phosphorylation; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D029721:Drosophila Proteins; D018994:Myosin Light Chains; D015879:Myosin Subfragments; D011994:Recombinant Proteins; D024507:Nonmuscle Myosin Type IIA
keywords: D. melanogaster; cell biology; developmental biology; epithelial cells; morphogenesis; myosin; stem cells