title: Regulation of focal adhesion targeting and inhibitory functions of the FAK related protein FRNK using a novel estrogen receptor "switch".
abstract: Focal adhesion kinase (FAK) is a regulator of numerous adhesion-dependent processes including cell migration, cell proliferation, and cell survival. The C-terminal domain of FAK, FAK-related nonkinase (FRNK), is autonomously expressed and functions as an inhibitor of FAK signaling. Previous attempts to use FRNK as a tool to dissect FAK signaling have been limited because of an inability to temporally regulate the inhibitory functions of FRNK. In this report, we describe and characterize a conditionally targeted form of FRNK that was created by fusing the hormone-binding domain of the estrogen receptor (ER*) to the C-terminus of FRNK. In the absence of added hormone, FRNK-ER* was diffusely distributed throughout the cytoplasm of cells. Upon addition of hormone, the cytoplasmic pool of FRNK-ER* was rapidly redistributed to focal adhesions. We demonstrate that cells expressing FRNK-ER* show a hormone-dependent decrease in FAK tyrosine phosphorylation and cell migration. Furthermore, when cells expressing of FRNK-ER* were treated with hormone, the cells responded with a dramatic change in cell morphology, suggesting a role for FAK in the regulation of the adhesive properties of focal adhesions.
authors.affiliation: Department of Microbiology, University of Virginia Health System, Charlottesville, Virginia 22908, USA.
authors.forename: Karen H
authors.initials: KH
authors.lastname: Martin
authors.forename: Scott A
authors.initials: SA
authors.lastname: Boerner
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Parsons
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D048429:Cell Size / Q000187:drug effects; D002478:Cells, Cultured; D005347:Fibroblasts; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D022001:Focal Adhesions / Q000187:drug effects* / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000494:pharmacology*; D051381:Rats; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000494:pharmacology*; D013629:Tamoxifen / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D011960:Receptors, Estrogen; D011993:Recombinant Fusion Proteins; D013629:Tamoxifen; C016601:afimoxifene; C113183:FAK-related nonkinase; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496052:Ptk2 protein, rat