title: Expression patterns and roles of periostin during kidney and ureter development.
abstract: OBJECTIVE
  Periostin is a secreted extracellular matrix protein that is differentially expressed in the developing kidney. We analyzed the temporal-spatial expression of periostin in the developing kidney and ureter as well as its roles in ureter branching morphogenesis, nephrogenesis and ureter development.
  
  
  METHODS
  RNA in situ hybridization and immunofluorescence histochemistry were used to investigate the expression of periostin, αv integrin and α-smooth muscle actin during mouse renal and ureteral development. Metanephric explants were cultured in the presence of recombinant periostin, and ureteral branch points/tips and the glomerular number were quantified. Explants were also cultured in the presence of exogenous bone morphogenetic protein 4 and the effect on periostin mRNA levels was determined by quantitative real-time polymerase chain reaction.
  
  
  RESULTS
  Periostin expression was observed in the mesenchyme surrounding the kidney and ureter, renal stroma, metanephric mesenchyme, ureter epithelium and developing nephrons. At embryonic day 15.5 periostin and αv integrin, a common subunit of periostin receptors, were co-expressed in smooth muscle cells of the ureter, renal artery and intrarenal arteries. Bone morphogenetic protein 4 up-regulated periostin mRNA expression and exogenous periostin inhibited branching morphogenesis and glomerular number.
  
  
  CONCLUSIONS
  Bone morphogenetic protein 4 which inhibits ureteral branching morphogenesis and promotes smooth muscle cell migration in the ureter up-regulated periostin mRNA expression in the developing kidney. Ureteral smooth muscle cells express periostin and αv integrin. Periostin inhibited ureteral branching morphogenesis and glomerular number. Together these results suggest that periostin and bone morphogenetic protein 4 may have a role in branching morphogenesis, nephrogenesis and possibly smooth muscle cell migration.
authors.affiliation: Department of Anatomy and Developmental Biology, School of Biomedical Sciences, Monash University, Melbourne, Victoria, Australia.
authors.forename: Katrina
authors.initials: K
authors.lastname: Sorocos
authors.forename: Xenia
authors.initials: X
authors.lastname: Kostoulias
authors.forename: Luise
authors.initials: L
authors.lastname: Cullen-McEwen
authors.forename: Adam H
authors.initials: AH
authors.lastname: Hart
authors.forename: John F
authors.initials: JF
authors.lastname: Bertram
authors.forename: Georgina
authors.initials: G
authors.lastname: Caruana
mesh_terms: D000818:Animals; D055415:Bone Morphogenetic Protein 4 / Q000502:physiology; D015815:Cell Adhesion Molecules / Q000378:metabolism / Q000502:physiology*; D007150:Immunohistochemistry; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D007668:Kidney / Q000196:embryology* / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009024:Morphogenesis; D009924:Organ Culture Techniques; D019030:Receptors, Vitronectin / Q000378:metabolism; D014513:Ureter / Q000196:embryology* / Q000378:metabolism
chemical_list: C525810:Bmp4 protein, mouse; D055415:Bone Morphogenetic Protein 4; D015815:Cell Adhesion Molecules; D039302:Integrin alphaVbeta3; C082838:Postn protein, mouse; D019030:Receptors, Vitronectin; C064660:integrin alphaVbeta5