title: 14-3-3σ controls corneal epithelium homeostasis and wound healing.
abstract: OBJECTIVE
  To investigate the functional role of 14-3-3σ in regulation of the corneal epithelial proliferation, differentiation, and wound-healing response.
  
  
  METHODS
  Corneal phenotypes were investigated in heterozygous repeated epilation (Er) mice carrying mutations in the sfn (14-3-3σ) gene. Immunohistochemistry was used to study the corneal morphogenesis of the Er/Er embryos at embryonic day (E)18.5. Corneal homeostasis and the wound-healing response were investigated macroscopically and microscopically in the adult heterozygous Er mice. Corneal epithelial cell proliferation and differentiation were assessed by BrdU incorporation and immunohistochemistry with specific antibodies for differentiation markers. Furthermore, corneal stroma neovascularization and meibomian gland degeneration were examined by immunohistochemistry. The healing of corneal wounds after debridement was monitored and visualized by fluorescent staining.
  
  
  RESULTS
  Homozygous mutation of 14-3-3σ led to defects in embryonic corneal epithelial development and differentiation, whereas young heterozygotes showed normal corneal development and homeostasis. However, older heterozygotes displayed a dramatic corneal wound-healing defect characterized by hyperplastic basal progenitor cells (some of which undergo a differentiation switch to express markers of keratinized epidermis); cornea stroma changes including neovascularization; and corneal opacity, leading to plaque formation. Aged heterozygotes also showed meibomian gland atrophy.
  
  
  CONCLUSIONS
  14-3-3σ is essential for corneal epithelium differentiation, and plays an important role in corneal epithelium development and daily renewal of the adult corneal epithelium.
authors.affiliation: J. G. Brown Cancer Center, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA.
authors.forename: Qingxian
authors.initials: Q
authors.lastname: Lu
authors.forename: Ying
authors.initials: Y
authors.lastname: Xin
authors.forename: Fei
authors.initials: F
authors.lastname: Ye
authors.forename: Gary
authors.initials: G
authors.lastname: Foulks
authors.forename: Qiutang
authors.initials: Q
authors.lastname: Li
mesh_terms: D048948:14-3-3 Proteins / Q000502:physiology*; D000818:Animals; D001284:Atrophy; D015153:Blotting, Western; D002454:Cell Differentiation / Q000502:physiology*; D049109:Cell Proliferation; D019573:Epithelium, Corneal / Q000196:embryology* / Q000293:injuries / Q000473:pathology; D019084:Fluorescent Antibody Technique, Indirect; D006706:Homeostasis / Q000502:physiology*; D007765:Lacrimal Apparatus / Q000378:metabolism; D008537:Meibomian Glands / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009024:Morphogenesis; D010641:Phenotype; D014945:Wound Healing / Q000502:physiology*
chemical_list: D048948:14-3-3 Proteins; C499130:Sfn protein, mouse