title: Dynamic microtubules produce an asymmetric E-cadherin-Bazooka complex to maintain segment boundaries.
abstract: Distributing junctional components around the cell periphery is key for epithelial tissue morphogenesis and homeostasis. We discovered that positioning of dynamic microtubules controls the asymmetric accumulation of E-cadherin. Microtubules are oriented preferentially along the dorso-ventral axis in Drosophila melanogaster embryonic epidermal cells, and thus more frequently contact E-cadherin at dorso-ventral cell-cell borders. This inhibits RhoGEF2, reducing membrane recruitment of Rho-kinase, and increasing a specific E-cadherin pool that is mobile when assayed by fluorescence recovery after photobleaching. This mobile E-cadherin is complexed with Bazooka/Par-3, which in turn is required for normal levels of mobile E-cadherin. Mobile E-cadherin-Bazooka prevents formation of multicellular rosette structures and cell motility across the segment border in Drosophila embryos. Altogether, the combined action of dynamic microtubules and Rho signaling determines the level and asymmetric distribution of a mobile E-cadherin-Bazooka complex, which regulates cell behavior during the generation of a patterned epithelium.
authors.affiliation: Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, England, UK.
authors.forename: Natalia A
authors.initials: NA
authors.lastname: Bulgakova
authors.forename: Ilya
authors.initials: I
authors.lastname: Grigoriev
authors.forename: Alpha S
authors.initials: AS
authors.lastname: Yap
authors.forename: Anna
authors.initials: A
authors.lastname: Akhmanova
authors.forename: Nicholas H
authors.initials: NH
authors.lastname: Brown
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D015820:Cadherins / Q000378:metabolism*; D018797:Cell Cycle Proteins; D016764:Cell Polarity / Q000502:physiology; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D005260:Female; D049452:Green Fluorescent Proteins / Q000235:genetics; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D015820:Cadherins; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D046912:Multiprotein Complexes; C400774:baz protein, Drosophila; C465504:sav protein, Drosophila; C501889:shg protein, Drosophila; D049452:Green Fluorescent Proteins; D020741:rho GTP-Binding Proteins