title: RNAi-mediated inhibition of the desmosomal cadherin (desmoglein 3) impairs epithelial cell proliferation.
abstract: OBJECTIVE
  Desmoglein 3 (Dsg3) is a desmosomal adhesion protein expressed in basal and immediate suprabasal layers of skin. Importance of Dsg3 in cell-cell adhesion and maintenance of tissue integrity is illustrated by findings of keratinocyte dissociation in the autoimmune disease, pemphigus vulgaris, where autoantibodies target Dsg3 on keratinocyte surfaces and cause Dsg3 depletion from desmosomes. However, recognition of possible participation of involvement of Dsg3 in cell proliferation remains controversial. Currently, available evidence suggests that Dsg3 may have both anti- and pro-proliferative roles in keratinocytes. The aim of this study was to use RNA interference (RNAi) strategy to investigate effects of silencing Dsg3 in cell-cell adhesion and cell proliferation in two cell lines, HaCaT and MDCK.
  
  
  METHODS
  Cells were transfected with siRNA, and knockdown of Dsg3 was assessed by western blotting, fluorescence-activated cell sorting and confocal microscopy. Cell-cell adhesion was analysed using the hanging drop/fragmentation assay, and cell proliferation by colony forming efficiency, BrdU incorporation, cell counts and organotypic culture.
  
  
  RESULTS
  Silencing Dsg3 caused defects in cell-cell adhesion and concomitant reduction in cell proliferation in both HaCaT and MDCK cells.
  
  
  CONCLUSIONS
  These findings suggest that Dsg3 depletion by RNAi reduces cell proliferation, which is likely to be secondary to a defect in cell-cell adhesion, an essential function required for cell differentiation and morphogenesis.
authors.affiliation: Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Centre for Clinical and Diagnostic Oral Sciences, Institute of Dentistry, UK.
authors.forename: T
authors.initials: T
authors.lastname: Mannan
authors.forename: S
authors.initials: S
authors.lastname: Jing
authors.forename: S H
authors.initials: SH
authors.lastname: Foroushania
authors.forename: F
authors.initials: F
authors.lastname: Fortune
authors.forename: H
authors.initials: H
authors.lastname: Wan
mesh_terms: D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation; D051184:Desmoglein 3 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D003896:Desmosomes / Q000378:metabolism*; D004285:Dogs; D004847:Epithelial Cells / Q000502:physiology*; D006801:Humans; D034622:RNA Interference
chemical_list: C071894:DSG3 protein, human; D051184:Desmoglein 3