title: The spectraplakin Short stop is an essential microtubule regulator involved in epithelial closure inDrosophila.
abstract: Dorsal closure of theDrosophilaembryonic epithelium provides an excellent model system for thein vivoanalysis of molecular mechanisms regulating cytoskeletal rearrangements. In this study, we investigated the function of theDrosophilaspectraplakin Short stop (Shot), a conserved cytoskeletal structural protein, during closure of the dorsal embryonic epithelium. We show that Shot is essential for the efficient final zippering of the opposing epithelial margins. By using isoform-specific mutant alleles and genetic rescue experiments with truncated Shot variants, we demonstrate that Shot functions as an actin-microtubule cross-linker in mediating zippering. At the leading edge of epithelial cells, Shot regulates protrusion dynamics by promoting filopodia formation. Fluorescence recovery after photobleaching (FRAP) analysis andin vivoimaging of microtubule growth revealed that Shot stabilizes dynamic microtubules. The actin- and microtubule-binding activities of Shot are simultaneously required in the same molecule, indicating that Shot is engaged as a physical crosslinker in this process. We propose that Shot-mediated interactions between microtubules and actin filaments facilitate filopodia formation, which promotes zippering by initiating contact between opposing epithelial cells.
authors.affiliation: Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary.
authors.forename: Zsanett
authors.initials: Z
authors.lastname: Takács
authors.affiliation: Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary jankovics.ferenc@brc.mta.hu.
authors.forename: Ferenc
authors.identifier: 0000-0001-9697-4472
authors.initials: F
authors.lastname: Jankovics
authors.affiliation: Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary.
authors.forename: Péter
authors.initials: P
authors.lastname: Vilmos
authors.affiliation: Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, Heidelberg 69117, Germany.
authors.forename: Péter
authors.initials: P
authors.lastname: Lénárt
authors.affiliation: MRC-Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK.
authors.forename: Katja
authors.initials: K
authors.lastname: Röper
authors.affiliation: Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, Szeged 6726, Hungary.
authors.forename: Miklós
authors.initials: M
authors.lastname: Erdélyi
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D029721:Drosophila Proteins / Q000737:chemistry / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology / Q000378:metabolism*; D004625:Embryo, Nonmammalian / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D008840:Microfilament Proteins / Q000737:chemistry / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D009024:Morphogenesis; D009154:Mutation / Q000235:genetics; D000072417:Protein Domains; D011554:Pseudopodia / Q000378:metabolism
chemical_list: D000199:Actins; D029721:Drosophila Proteins; D008840:Microfilament Proteins; C450828:shot protein, Drosophila; D049452:Green Fluorescent Proteins
keywords: Actin; Dorsal closure; Drosophila; Microtubule; Short stop; Spectraplakin