title: Mucins: a biologically relevant glycan barrier in mucosal protection.
abstract: BACKGROUND
  The mucins found as components of mucus gel layers at mucosal surfaces throughout the body play roles in protection as part of the defensive barrier on an organ and tissue specific basis.
  
  
  OBJECTIVE
  The human MUC gene family codes up to 20 known proteins, which can be divided into secreted and membrane-associated forms each with a typical protein domain structure. The secreted mucins are adapted to cross link in order to allow formation of the extended mucin networks found in the secreted mucus gels. The membrane-associated mucins possess membrane specific domains which enable their various biological functions as part of the glycocalyx. All mucins are highly O-glycosylated and this is tissue specific and linked with specific biological functions at these locations. Mucin biology is dynamic and the processes of degradation and turnover are well integrated with biosynthesis to maintain a continuous mucosal protection against all external aggressive forces. Interaction of mucins with microflora plays an important role in normal function. Mucins are modified in a variety of diseases and this may be due to abberant mucin peptide or glycosylation.
  
  
  CONCLUSIONS
  Mucins represent a family of glycoprotein having fundamental roles in mucosal protection and communication with external environment.
  
  
  CONCLUSIONS
  The review emphasises the nature of mucins as glycoproteins and their role in presenting an array of glycan structures at the mucosal cell surface.
authors.affiliation: Mucin Research Group, University of Bristol, School of Clinical Sciences, Bristol Royal Infirmary, Bristol BS2 8HW, United Kingdom. Electronic address: corfielda@gmail.com.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Corfield
mesh_terms: D002241:Carbohydrates / Q000737:chemistry*; D004755:Enterobacteriaceae / Q000378:metabolism / Q000502:physiology; D054884:Host-Pathogen Interactions; D006801:Humans; D008954:Models, Biological; D009077:Mucins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009092:Mucous Membrane / Q000378:metabolism* / Q000382:microbiology; D005810:Multigene Family / Q000235:genetics; D009369:Neoplasms / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry
chemical_list: D002241:Carbohydrates; D009077:Mucins; D011134:Polysaccharides
keywords: Cancer; Glycosylation; Microflora; Mucin; Mucosal; Mucus