title: Use of microarray analysis to study gene expression in the avian epiphyseal growth plate.
abstract: Longitudinal bone growth depends upon the execution of an intricate series of cellular activities by epiphyseal growth plate chondrocytes. In order to better understand these coordinated events, microarray analysis was used to compare gene expression in chondrocytes isolated from the proliferative and hypertrophic zones of the avian growth plate. RT-PCR was used to confirm the identity of a select number of genes. The expression of 745 genes was found to differ 3-fold or greater at the 0.05 level of probability. Transferrin was the most highly up-regulated (321-fold) gene associated with chondrocyte hypertrophy. Immunohistochemistry localized this peptide adjacent to the penetrating blood vessels in the growth plate of 3-week-old chicks. Fibulin, OC-116, DMP-1 and PHEX were among the expanded number of genes associated with extracellular matrix metabolism. The presence of NELL2, ATOH8 and PLEXIN suggests a neuronal involvement in growth plate physiology. In addition, the expression of a large number of genes associated with angiogenesis and cellular stress was up-regulated. These processes are important to the physiology and survival of chondrocytes in the unique and stressful environment of the epiphyseal growth plate.
authors.affiliation: Department of Poultry Science, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: M
authors.initials: M
authors.lastname: Horvat-Gordon
authors.forename: C A
authors.initials: CA
authors.lastname: Praul
authors.forename: R
authors.initials: R
authors.lastname: Ramachandran
authors.forename: P A
authors.initials: PA
authors.lastname: Bartell
authors.forename: R M
authors.initials: RM
authors.lastname: Leach
mesh_terms: D000818:Animals; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D049109:Cell Proliferation; D002645:Chickens / Q000235:genetics* / Q000254:growth & development*; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism; D004838:Epiphyses / Q000254:growth & development* / Q000378:metabolism*; D005109:Extracellular Matrix / Q000201:enzymology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006132:Growth Plate / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D017136:Ion Transport / Q000235:genetics; D050356:Lipid Metabolism / Q000235:genetics; D018919:Neovascularization, Physiologic / Q000235:genetics; D009474:Neurons / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D011453:Prostaglandins / Q000235:genetics / Q000378:metabolism; D051140:Selenoproteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014212:Tretinoin / Q000378:metabolism; D014284:Triiodothyronine / Q000378:metabolism
chemical_list: D019485:Bone Morphogenetic Proteins; D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; D011453:Prostaglandins; D051140:Selenoproteins; D014157:Transcription Factors; D014284:Triiodothyronine; D014212:Tretinoin; D010088:Oxidoreductases