title: Rho1 regulates Drosophila adherens junctions independently of p120ctn.
abstract: During animal development, adherens junctions (AJs) maintain epithelial cell adhesion and coordinate changes in cell shape by linking the actin cytoskeletons of adjacent cells. Identifying AJ regulators and their mechanisms of action are key to understanding the cellular basis of morphogenesis. Previous studies linked both p120catenin and the small GTPase Rho to AJ regulation and revealed that p120 may negatively regulate Rho. Here we examine the roles of these candidate AJ regulators during Drosophila development. We found that although p120 is not essential for development, it contributes to morphogenesis efficiency, clarifying its role as a redundant AJ regulator. Rho has a dynamic localization pattern throughout ovarian and embryonic development. It preferentially accumulates basally or basolaterally in several tissues, but does not preferentially accumulate in AJs. Further, Rho1 localization is not obviously altered by loss of p120 or by reduction of core AJ proteins. Genetic and cell biological tests suggest that p120 is not a major dose-sensitive regulator of Rho1. However, Rho1 itself appears to be a regulator of AJs. Loss of Rho1 results in ectopic accumulation of cytoplasmic DE-cadherin, but ectopic cadherin does not accumulate with its partner Armadillo. These data suggest Rho1 regulates AJs during morphogenesis, but this regulation is p120 independent.
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
authors.forename: Donald T
authors.initials: DT
authors.lastname: Fox
authors.forename: Catarina C F
authors.initials: CC
authors.lastname: Homem
authors.forename: Steven H
authors.initials: SH
authors.lastname: Myster
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.forename: E Eugene
authors.initials: EE
authors.lastname: Bain
authors.forename: Mark
authors.initials: M
authors.lastname: Peifer
mesh_terms: D022005:Adherens Junctions / Q000378:metabolism*; D000818:Animals; D051186:Armadillo Domain Proteins / Q000378:metabolism; D051177:Catenins; D015815:Cell Adhesion Molecules / Q000502:physiology*; D051181:Desmosomal Cadherins / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000254:growth & development; D029721:Drosophila Proteins / Q000378:metabolism / Q000502:physiology; D004625:Embryo, Nonmammalian; D005260:Female; D009024:Morphogenesis; D010750:Phosphoproteins / Q000502:physiology*; D014018:Tissue Distribution; D014157:Transcription Factors / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism / Q000502:physiology*; D000095002:Delta Catenin
chemical_list: C495305:ARM protein, Drosophila; D051186:Armadillo Domain Proteins; D051177:Catenins; D015815:Cell Adhesion Molecules; D051181:Desmosomal Cadherins; D029721:Drosophila Proteins; D010750:Phosphoproteins; D014157:Transcription Factors; C511153:Rho1 protein, Drosophila; D020741:rho GTP-Binding Proteins; D000095002:Delta Catenin