title: Regulation of keratinocyte differentiation by O-GlcNAcylation.
abstract: BACKGROUND
  O-linked β-N-acetylglucosamine (O-GlcNAc) modification is one of the posttranslational modification, emerging as an important regulatory mechanism in various cellular events.
  
  
  OBJECTIVE
  We attempted to investigate whether O-GlcNAcylation is involved in keratinocyte differentiation.
  
  
  METHODS
  Immunohistochemistry and Western blot were performed to demonstrate O-GlcNAcylation in keratinocyte differentiation.
  
  
  RESULTS
  During calcium-induced keratinocyte differentiation, overall O-GlcNAcylation was decreased in a temporal manner. We focused our attention on transcription factor Sp-1, which is implicated in keratinocyte differentiation. Total Sp-1 level did not change during keratinocyte differentiation. However, O-GlcNAcylated Sp-1 was decreased in a keratinocyte differentiation-dependent manner. Interestingly, transcriptional activity of Sp-1, in terms of involucrin and loricrin promoter activities, was markedly increased by overexpression of O-GlcNAcase (OGA). In addition, membrane permeable non-O-GlcNAcylated Sp-1 did show transcriptional activity, while membrane permeable O-GlcNAcylated Sp-1 did not, suggesting O-GlcNAcylated Sp-1 is an inactive form in keratinocyte differentiation.
  
  
  CONCLUSIONS
  Our results reveal that O-GlcNAcylation is a dynamic regulatory mechanism for keratinocyte differentiation.
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Kyung-Cheol
authors.initials: KC
authors.lastname: Sohn
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Eun Jin
authors.initials: EJ
authors.lastname: Lee
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Jung-Min
authors.initials: JM
authors.lastname: Shin
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Eun-Hwa
authors.initials: EH
authors.lastname: Lim
authors.affiliation: Department of Dermatology, School of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea.
authors.forename: Yoonoo
authors.initials: Y
authors.lastname: No
authors.affiliation: Department of Dermatology, School of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea.
authors.forename: Ji Yeoun
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Dermatology, School of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea.
authors.forename: Tae Young
authors.initials: TY
authors.lastname: Yoon
authors.affiliation: Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Myung
authors.initials: M
authors.lastname: Im
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Young
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Young-Joon
authors.initials: YJ
authors.lastname: Seo
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Jeung-Hoon
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Dermatology and Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, Republic of Korea. Electronic address: cdkimd@gmail.com.
authors.forename: Chang Deok
authors.initials: CD
authors.lastname: Kim
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002454:Cell Differentiation; D002478:Cells, Cultured; D006031:Glycosylation; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D016329:Sp1 Transcription Factor / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic; D014162:Transfection; D001619:beta-N-Acetylhexosaminidases / Q000235:genetics / Q000378:metabolism
chemical_list: D008565:Membrane Proteins; D011498:Protein Precursors; D016329:Sp1 Transcription Factor; C108209:SP1 protein, human; C064554:loricrin; C032253:involucrin; C110628:hexosaminidase C; D001619:beta-N-Acetylhexosaminidases; D002118:Calcium; D000117:Acetylglucosamine
keywords: Keratinocyte differentiation; O-GlcNAcylation; Sp-1