title: Spatial regulation of gene expression during growth of articular cartilage in juvenile mice.
abstract: BACKGROUND
  In juvenile mammals, the epiphyses of long bones grow by chondrogenesis within the articular cartilage. A better understanding of the molecular mechanisms that regulate the growth of articular cartilage may give insight into the antecedents of joint disease, such as osteoarthritis.
  
  
  METHODS
  We used laser capture microdissection to isolate chondrocytes from the superficial, middle, and deep zones of growing tibial articular cartilage in the 1-wk-old mouse and then investigated expression patterns by microarray. To identify molecular markers for each zone of the growing articular cartilage, we found genes showing zone-specific expression and confirmed by real-time PCR and in situ hybridization.
  
  
  RESULTS
  Bioinformatic analyses implicated ephrin receptor signaling, Wnt signaling, and bone morphogenetic protein signaling in the spatial regulation of chondrocyte differentiation during growth. Molecular markers were identified for superficial (e.g., Cilp, Prg4), middle (Cxcl14, Tnn), and deep zones (Sfrp5, Frzb). Comparison between juvenile articular and growth plate cartilage revealed that the superficial-to-deep zone transition showed similarity with the hypertrophic-to-resting zone transition.
  
  
  CONCLUSIONS
  Laser capture microdissection combined with microarray analysis identified novel signaling pathways that are spatially regulated in growing mouse articular cartilage and revealed similarities between the molecular architecture of the growing articular cartilage and that of growth plate cartilage.
authors.affiliation: Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland.
authors.forename: Julian C
authors.initials: JC
authors.lastname: Lui
authors.affiliation: Center for Molecular Medicine and Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Michael
authors.initials: M
authors.lastname: Chau
authors.affiliation: The Genomics Core Laboratory, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland.
authors.forename: Weiping
authors.initials: W
authors.lastname: Chen
authors.affiliation: Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland.
authors.forename: Crystal S F
authors.initials: CS
authors.lastname: Cheung
authors.affiliation: Laser Capture Microdissection Core Facility, Laboratory of Pathology, National Cancer Institute (NCI), NIH, Bethesda, Maryland.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Hanson
authors.affiliation: Laser Capture Microdissection Core Facility, Laboratory of Pathology, National Cancer Institute (NCI), NIH, Bethesda, Maryland.
authors.forename: Jaime
authors.initials: J
authors.lastname: Rodriguez-Canales
authors.affiliation: 1] Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland [2] Center for Molecular Medicine and Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Ola
authors.initials: O
authors.lastname: Nilsson
authors.affiliation: Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, Maryland.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Baron
mesh_terms: D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D002358:Cartilage, Articular / Q000254:growth & development* / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D020219:Chondrogenesis / Q000502:physiology*; D019295:Computational Biology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D017403:In Situ Hybridization; D061346:Laser Capture Microdissection; D051379:Mice; D046228:Microarray Analysis; D060888:Real-Time Polymerase Chain Reaction; D036081:Receptors, Eph Family / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D051153:Wnt Proteins / Q000378:metabolism
chemical_list: D019485:Bone Morphogenetic Proteins; D051153:Wnt Proteins; D036081:Receptors, Eph Family