title: Involvement of p27(KIP1) degradation by Skp2 in the regulation of proliferation in response to wounding of corneal epithelium.
abstract: OBJECTIVE
  To examine the expression of the p27(KIP1)in the normal and epithelial-scraped cornea and whether degradation of p27(KIP1)by Skp2 is involved in the regulation of cell proliferation in response to wounding of the corneal epithelium.
  
  
  METHODS
  C57Bl6, p27(KIP1-/-), Skp2(-/-), and Skp2(-/-)/p27(KIP1-/-) double-knockout mice were examined. Normal and epithelial-scraped corneas were analyzed by immunocytochemistry using anti-p27(KIP1) antibody. Cells in the S phase of DNA synthesis were analyzed by immunocytochemistry using anti-bromodeoxyuridine (BrdU) antibody.
  
  
  RESULTS
  The p27(KIP1) was expressed in basal cells of the central and peripheral region of the cornea and limbus. This expression was not detected 24 hours after the epithelial scraping, when there were many cells in the S phase of DNA synthesis in the corneal epithelium. There were no obvious differences in the thickness and anti-BrdU staining in the corneal epithelium of p27(KIP1-/-) mice from that of control animals. Twenty-four hours after epithelial scraping in the Skp2(-/-) mice, the corneal epithelium was thinner than in wild-type mice and had many p27(KIP1)-positive cells and few BrdU-positive cells. In contrast, 24 hours after epithelial scraping in the Skp2(-/-)/p27(KIP1)(-/-) double-knockout mice, the corneal epithelium was as thick as in wild-type mice and had many BrdU-positive cells.
  
  
  CONCLUSIONS
  These results suggest that degradation of p27(KIP1) by Skp2 is involved in the regulation of cell proliferation in response to wounding of the corneal epithelium.
authors.affiliation: Department of Ophthalmology, Hokkaido University School of Medicine, Sapporo, Japan. kyoshida@med.hokudai.ac.jp
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Yoshida
authors.forename: Keiko
authors.initials: K
authors.lastname: Nakayama
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Nagahama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Harada
authors.forename: Chikako
authors.initials: C
authors.lastname: Harada
authors.forename: Junko
authors.initials: J
authors.lastname: Imaki
authors.forename: Akira
authors.initials: A
authors.lastname: Matsuda
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Miyuki
authors.initials: M
authors.lastname: Ito
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Ohno
authors.forename: Kei-Ichi
authors.initials: K
authors.lastname: Nakayama
mesh_terms: D000818:Animals; D018797:Cell Cycle Proteins / Q000378:metabolism* / Q000502:physiology*; D002455:Cell Division; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors; D004247:DNA / Q000096:biosynthesis; D004261:DNA Replication; D004791:Enzyme Inhibitors / Q000378:metabolism*; D019573:Epithelium, Corneal / Q000293:injuries* / Q000378:metabolism / Q000473:pathology; D005131:Eye Injuries / Q000378:metabolism* / Q000473:pathology; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D044786:S-Phase Kinase-Associated Proteins; D025521:Tumor Suppressor Proteins / Q000378:metabolism*; D014945:Wound Healing
chemical_list: C493961:Cdkn1b protein, mouse; D018797:Cell Cycle Proteins; D004791:Enzyme Inhibitors; D044786:S-Phase Kinase-Associated Proteins; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004247:DNA; D018844:Cyclin-Dependent Kinases