title: Adherens junctions determine the apical position of the midbody during follicular epithelial cell division.
abstract: Cytokinesis is asymmetric along the apical-basal axis of epithelial cells, positioning the midbody near the apical domain. However, little is known about the mechanism and purpose of this asymmetry. We use live imaging of Drosophila follicle cell division to show that asymmetric cytokinesis does not result from intrinsic polarization of the main contractile ring components. We show that adherens junctions (AJs) maintain close contact with the apical side of the contractile ring during cytokinesis. Asymmetric distribution of AJ components within follicle cells and in the otherwise unpolarized S2 cells is sufficient to recruit the midbody, revealing that asymmetric cytokinesis is determined by apical AJs in the epithelia. We further show that ectopic midbody localization induces epithelial invaginations, shifting the position of the apical interface between daughter cells relative to the AB axis of the tissue. Thus, apical midbody localization is essential to maintain epithelial tissue architecture during proliferation.
authors.affiliation: Instituto de Biologia Molecular e Celular, Rua do Campo Alegre, 823, Porto P-4150-180, Portugal.
authors.forename: Eurico
authors.initials: E
authors.lastname: Morais-de-Sá
authors.forename: Claudio
authors.initials: C
authors.lastname: Sunkel
mesh_terms: D022005:Adherens Junctions / Q000502:physiology* / Q000648:ultrastructure; D000818:Animals; D016764:Cell Polarity; D003285:Contractile Proteins / Q000235:genetics / Q000378:metabolism; D048749:Cytokinesis; D004330:Drosophila / Q000166:cytology / Q000502:physiology* / Q000648:ultrastructure; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004847:Epithelial Cells / Q000502:physiology* / Q000648:ultrastructure; D015870:Gene Expression; D016547:Kinesins / Q000235:genetics / Q000378:metabolism; D018994:Myosin Light Chains / Q000235:genetics / Q000378:metabolism; D024462:Myosin Type II / Q000235:genetics / Q000378:metabolism; D059008:Time-Lapse Imaging
chemical_list: D003285:Contractile Proteins; D029721:Drosophila Proteins; D018994:Myosin Light Chains; C495593:Sqh protein, Drosophila; C095886:anillin; D024462:Myosin Type II; D016547:Kinesins