Rho1 interacts with p120ctn and alpha-catenin, and regulates cadherin-based adherens junction components in Drosophila.
Rho GTPases are important regulators of cellular behavior through their effects on processes such as cytoskeletal organization. Here we show interactions between Drosophila Rho1 and the adherens junction components alpha-catenin and p120(ctn). We find that while Rho1 protein is present throughout the cell, it accumulates apically, particularly at sites of cadherin-based adherens junctions. Cadherin and catenin localization is disrupted in Rho1 mutants, implicating Rho1 in their regulation. p120(ctn) has recently been suggested to inhibit Rho activity through an unknown mechanism. We find that Rho1 accumulates in response to lowered p120(ctn) activity. Significantly, we find that Rho1 binds directly to alpha-catenin and p120(ctn) in vitro, and these interactions map to distinct surface-exposed regions of the protein not previously assigned functions. In addition, we find that both alpha-catenin and p120(ctn) co-immunoprecipitate with Rho1-containing complexes from embryo lysates. Our observations suggest that alpha-catenin and p120(ctn) are key players in a mechanism of recruiting Rho1 to its sites of action.
Division of Basic Sciences and Program in Developmental Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
Craig R
CR
Magie
Delia
D
Pinto-Santini
Susan M
SM
Parkhurst
D022005:Adherens Junctions / Q000378:metabolism; D000818:Animals; D000911:Antibodies, Monoclonal; D001665:Binding Sites; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D051177:Catenins; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D066298:In Vitro Techniques; D008954:Models, Biological; D008958:Models, Molecular; D009154:Mutation; D010053:Ovary / Q000378:metabolism; D010641:Phenotype; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D051178:alpha Catenin; D020741:rho GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D000095002:Delta Catenin
D000911:Antibodies, Monoclonal; D015820:Cadherins; D051177:Catenins; D015815:Cell Adhesion Molecules; D003598:Cytoskeletal Proteins; D029721:Drosophila Proteins; D010750:Phosphoproteins; D051178:alpha Catenin; C511153:Rho1 protein, Drosophila; D020741:rho GTP-Binding Proteins; D000095002:Delta Catenin