title: Modulation of cell morphogenesis by tousled-like kinase in the Drosophila follicle cell.
abstract: BACKGROUND
  Tousled-like kinase (Tlk) is a conserved serine/threonine kinase regulating DNA replication, chromatin assembly, and DNA repair. Previous studies have suggested that Tlk is involved in cell morphogenesis in vitro. In addition, tlk genetically interact with Rho1, which encodes a key regulator of the cytoskeleton. However, whether Tlk plays a physiological role in cell morphogenesis and cytoskeleton rearrangement remains unknown.
  
  
  RESULTS
  In tlk mutant follicle cells, area of the apical domain was reduced. The density of microtubules was increased in tlk mutant cells. The density of actin filaments was increased in the apical region and decreased in the basal region. Because area of the apical domain was reduced, we examined the levels of proteins located in the apical region by using immunofluorescence. The fluorescence intensities of two adherens junction proteins Armadillo (Arm) and DE-cadherin (DE-cad), atypical protein kinase C (aPKC), and Notch, were all increased in tlk mutant cells. The basolateral localized Discs large (Dlg) shifted apically in tlk mutant cells.
  
  
  CONCLUSIONS
  Increase of protein densities in the apical region might be resulted from disruption of the cytoskeleton and shrinkage of the apical domain. Together, these data suggest a novel role of Tlk in maintaining cell morphology, possibly through modulating the cytoskeleton.
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Tsung-Han
authors.initials: TH
authors.lastname: Yeh
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shu-Yu
authors.initials: SY
authors.lastname: Huang
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Wan-Yu
authors.initials: WY
authors.lastname: Lan
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Gwo-Jen
authors.initials: GJ
authors.lastname: Liaw
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.|Brain Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Jenn-Yah
authors.initials: JY
authors.lastname: Yu
mesh_terms: D000818:Animals; D051186:Armadillo Domain Proteins / Q000235:genetics / Q000378:metabolism; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster; D008870:Microtubules / Q000201:enzymology* / Q000235:genetics; D009024:Morphogenesis / Q000502:physiology*; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D051880:Receptors, Notch / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: C495305:ARM protein, Drosophila; D051186:Armadillo Domain Proteins; D015820:Cadherins; D029721:Drosophila Proteins; C497759:N protein, Drosophila; D051880:Receptors, Notch; D014157:Transcription Factors; C501889:shg protein, Drosophila; C498930:tlk protein, Drosophila; D017346:Protein Serine-Threonine Kinases; C115015:PKC-3 protein; D011493:Protein Kinase C
keywords: actin filament; cell polarity; cytoskeleton; microtubule; oogenesis