title: Cytokinesis involves a nontranscriptional function of the Hippo pathway effector YAP.
abstract: YAP is a transcriptional coactivator that controls organ expansion and differentiation and is inhibited by the Hippo pathway in cells in interphase. Here, we demonstrated that, during mitosis, YAP localized to the midbody and spindle, subcellular structures that are involved in cytokinesis, the process by which contraction of the cytoskeleton produces two daughter cells. Furthermore, YAP was phosphorylated by CDK1, a kinase that promotes cell cycle progression. Knockdown of YAP by shRNA or expression of a nonphosphorylatable form of YAP delayed the separation of daughter cells (called abscission) and induced a cytokinesis phenotype associated with increased contractile force, membrane blebbing and bulges, and abnormal spindle orientation. Consequently, these defects led to an increased frequency of multinucleation, micronuclei, and aneuploidy. YAP was required for proper localization of proteins that regulate contraction during cytokinesis, including ECT2, MgcRacGap, Anillin, and RHOA. In addition, depletion of YAP increased the phosphorylation of myosin light chain, which would be expected to activate the contractile activity of myosin II, the molecular motor involved in cytokinesis. The polarity scaffold protein PATJ coprecipitated with YAP and colocalized with YAP at the cytokinesis midbody, and knockdown of PATJ phenocopied the cytokinetic defects and spindle orientation alterations induced by either YAP depletion or expression of a nonphosphorylatable YAP mutant. Together, these results reveal an unanticipated role for YAP in the proper organization of the cytokinesis machinery during mitosis through interaction with the polarity protein PATJ.
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Duyen Amy
authors.initials: DA
authors.lastname: Bui
authors.affiliation: The Ronald O. Perelman Department of Dermatology and the Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA.
authors.forename: Wendy
authors.initials: W
authors.lastname: Lee
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Anne E
authors.initials: AE
authors.lastname: White
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: J Wade
authors.initials: JW
authors.lastname: Harper
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Ron C J
authors.initials: RC
authors.lastname: Schackmann
authors.affiliation: BCMB (Biochemistry, Cell, and Molecular Biology) Allied Program, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA. Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Overholtzer
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Laura M
authors.initials: LM
authors.lastname: Selfors
authors.affiliation: Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA. joan_brugge@hms.harvard.edu.
authors.forename: Joan S
authors.initials: JS
authors.lastname: Brugge
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D016203:CDC2 Protein Kinase; D002460:Cell Line; D003285:Contractile Proteins / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D048749:Cytokinesis / Q000235:genetics / Q000502:physiology*; D020690:GTPase-Activating Proteins / Q000378:metabolism; D006367:HeLa Cells; D000090683:Hippo Signaling Pathway; D006801:Humans; D015151:Immunoblotting; D018613:Microscopy, Confocal; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D034622:RNA Interference; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*; D062725:Tight Junction Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors; D000091102:YAP-Signaling Proteins; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D003285:Contractile Proteins; C489850:ECT2 protein, human; D020690:GTPase-Activating Proteins; C107903:PATJ protein, human; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D062725:Tight Junction Proteins; D014157:Transcription Factors; D000091102:YAP-Signaling Proteins; C088374:YAP1 protein, human; C095886:anillin; C115995:mgcRacGAP; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; C528899:CDK1 protein, human; D018844:Cyclin-Dependent Kinases; D020742:rhoA GTP-Binding Protein