The Frizzled-dependent planar polarity pathway locally promotes E-cadherin turnover via recruitment of RhoGEF2.
Polarised tissue elongation during morphogenesis involves cells within epithelial sheets or tubes making and breaking intercellular contacts in an oriented manner. Growing evidence suggests that cell adhesion can be modulated by endocytic trafficking of E-cadherin (E-cad), but how this process can be polarised within individual cells is poorly understood. The Frizzled (Fz)-dependent core planar polarity pathway is a major regulator of polarised cell rearrangements in processes such as gastrulation, and has also been implicated in regulation of cell adhesion through trafficking of E-cad; however, it is not known how these functions are integrated. We report a novel role for the core planar polarity pathway in promoting cell intercalation during tracheal tube morphogenesis in Drosophila embryogenesis, and present evidence that this is due to regulation of turnover and levels of junctional E-cad by the guanine exchange factor RhoGEF2. Furthermore, we show that core pathway activity leads to planar-polarised recruitment of RhoGEF2 and E-cad turnover in the epidermis of both the embryonic germband and the pupal wing. We thus reveal a general mechanism by which the core planar polarity pathway can promote polarised cell rearrangements.
MRC Centre for Developmental and Biomedical Genetics, and Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
Samantha J
SJ
Warrington
Helen
H
Strutt
David
D
Strutt
D000818:Animals; D030801:Animals, Genetically Modified; D019521:Body Patterning / Q000235:genetics* / Q000502:physiology; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins; D016764:Cell Polarity / Q000235:genetics* / Q000502:physiology; D002478:Cells, Cultured; D004330:Drosophila / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D004625:Embryo, Nonmammalian; D051157:Frizzled Receptors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D011485:Protein Binding; D021381:Protein Transport / Q000502:physiology; D059748:Proteolysis; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D014132:Trachea / Q000196:embryology / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism* / Q000502:physiology
D015820:Cadherins; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D051157:Frizzled Receptors; C058784:fz protein, Drosophila; C465504:sav protein, Drosophila; D020741:rho GTP-Binding Proteins