title: The S100 proteins in epidermis: Topology and function.
abstract: BACKGROUND
  S100 proteins are small calcium binding proteins encoded by genes located in the epidermal differentiation complex (EDC). Differently to other proteins encoded by EDC genes, which are indispensable for normal epidermal differentiation, the role of S100 proteins in the epidermis remains largely unknown.
  
  
  METHODS
  Particular S100 proteins differ in their distribution in epidermal layers, skin appendages, melanocytes and Langerhans cells. Taking into account that each epidermal component consists of specialized cells with well-defined functions, such differential distribution may be indicative of the function of a given S100 protein. We used this criterion together with the survey of the current experimental data pertinent to epidermis to provide a fairly comprehensive view on the possible function of individual S100 proteins in this tissue.
  
  
  CONCLUSIONS
  S100 proteins are differently expressed and, despite extensive structural homology, perform diverse functions in the epidermis. Certain S100 proteins probably ensure constant epidermal renewal and support wound healing while others act in epidermal differentiation or have a protective role. As their expression is differently affected in various skin pathologies, particular S100 proteins could be valuable diagnostic markers.
  
  
  CONCLUSIONS
  S100 proteins seem to be important although not yet fully recognized epidermal constituents. Better understanding of their role in the epidermis might be helpful in designing therapies to various skin diseases.
authors.affiliation: Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, 3 Pasteur Street, 02-093 Warsaw, Poland. Electronic address: w.lesniak@nencki.gov.pl.
authors.forename: Wiesława
authors.initials: W
authors.lastname: Leśniak
authors.affiliation: Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, 3 Pasteur Street, 02-093 Warsaw, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Graczyk-Jarzynka
mesh_terms: D000818:Animals; D004817:Epidermis / Q000378:metabolism*; D006801:Humans; D009418:S100 Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*
chemical_list: D009418:S100 Proteins
keywords: Epidermal differentiation complex (EDC); Epidermis; Keratinocyte; Langerhans cells; Melanocytes; S100 proteins