title: Adhesion to fibronectin regulates Hippo signaling via the FAK-Src-PI3K pathway.
abstract: The Hippo pathway is involved in the regulation of contact inhibition of proliferation and responses to various physical and chemical stimuli. Recently, several upstream negative regulators of Hippo signaling, including epidermal growth factor receptor ligands and lysophosphatidic acid, have been identified. We show that fibronectin adhesion stimulation of focal adhesion kinase (FAK)-Src signaling is another upstream negative regulator of the Hippo pathway. Inhibition of FAK or Src in MCF-10A cells plated at low cell density prevented the activation of Yes-associated protein (YAP) in a large tumor suppressor homologue (Lats)-dependent manner. Attachment of serum-starved MCF-10A cells to fibronectin, but not poly-d-lysine or laminin, induced YAP nuclear accumulation via the FAK-Src-phosphatidylinositol 4,5-bisphosphate 3-kinase (PI3K) signaling pathway. Attenuation of FAK, Src, PI3K, or PDK1 activity blocked YAP nuclear accumulation stimulated by adhesion to fibronectin. This negative regulation of the Hippo pathway by fibronectin adhesion signaling can, at least in part, explain the effects of cell spreading on YAP nuclear localization and represents a Lats-dependent component of the response to cell adhesion.
authors.affiliation: Department of Cell Biology, University of Virginia Health Sciences Center, Charlottesville, VA 22908.
authors.forename: Nam-Gyun
authors.initials: NG
authors.lastname: Kim
authors.affiliation: Department of Cell Biology, University of Virginia Health Sciences Center, Charlottesville, VA 22908 gumbiner@virginia.edu.
authors.forename: Barry M
authors.initials: BM
authors.lastname: Gumbiner
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000037:antagonists & inhibitors; D002460:Cell Line; D049109:Cell Proliferation / Q000502:physiology; D003260:Contact Inhibition / Q000502:physiology; D005353:Fibronectins / Q000378:metabolism*; D051417:Focal Adhesion Kinase 1 / Q000235:genetics / Q000378:metabolism*; D000090683:Hippo Signaling Pathway; D006801:Humans; D007797:Laminin / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010750:Phosphoproteins / Q000037:antagonists & inhibitors; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000037:antagonists & inhibitors / Q000378:metabolism; D011107:Polylysine / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering; D015398:Signal Transduction; D014157:Transcription Factors; D000091102:YAP-Signaling Proteins; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D005353:Fibronectins; D051417:Focal Adhesion Kinase 1; D007797:Laminin; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010750:Phosphoproteins; D017853:Phosphotransferases (Alcohol Group Acceptor); D011107:Polylysine; D017346:Protein Serine-Threonine Kinases; D034741:RNA, Small Interfering; D014157:Transcription Factors; D000091102:YAP-Signaling Proteins; D019061:src-Family Kinases; C088374:YAP1 protein, human; C092745:LATS1 protein, human; C068961:phosphatidylinositol 4,5-biphosphate kinase; C496050:PTK2 protein, human