title: New tools for studying osteoarthritis genetics in zebrafish.
abstract: OBJECTIVE
  Increasing evidence points to a strong genetic component to osteoarthritis (OA) and that certain changes that occur in osteoarthritic cartilage recapitulate the developmental process of endochondral ossification. As zebrafish are a well validated model for genetic studies and developmental biology, our objective was to establish the spatiotemporal expression pattern of a number of OA susceptibility genes in the larval zebrafish providing a platform for functional studies into the role of these genes in OA.
  
  
  METHODS
  We identified the zebrafish homologues for Mcf2l, Gdf5, PthrP/Pthlh, Col9a2, and Col10a1 from the Ensembl genome browser. Labelled probes were generated for these genes and in situ hybridisations were performed on wild type zebrafish larvae. In addition, we generated transgenic reporter lines by modification of bacterial artificial chromosomes (BACs) containing full length promoters for col2a1 and col10a1.
  
  
  RESULTS
  For the first time, we show the spatiotemporal expression pattern of Mcf2l. Furthermore, we show that all six putative OA genes are dynamically expressed during zebrafish larval development, and that all are expressed in the developing skeletal system. Furthermore, we demonstrate that the transgenic reporters we have generated for col2a1 and col10a1 can be used to visualise chondrocyte hypertrophy in vivo.
  
  
  CONCLUSIONS
  In this study we describe the expression pattern of six OA susceptibility genes in zebrafish larvae and the generation of two new transgenic lines marking chondrocytes at different stages of maturation. Moreover, the tools used demonstrate the utility of the zebrafish model for functional studies on genes identified as playing a role in OA.
authors.affiliation: Department of Biochemistry, University of Bristol, Bristol, UK.
authors.forename: R E
authors.initials: RE
authors.lastname: Mitchell
authors.forename: L F A
authors.initials: LF
authors.lastname: Huitema
authors.forename: R E H
authors.initials: RE
authors.lastname: Skinner
authors.forename: L H
authors.initials: LH
authors.lastname: Brunt
authors.forename: C
authors.initials: C
authors.lastname: Severn
authors.forename: S
authors.initials: S
authors.lastname: Schulte-Merker
authors.forename: C L
authors.initials: CL
authors.lastname: Hammond
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D019902:Chondrocytes / Q000473:pathology; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D024081:Collagen Type IX / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D024121:Collagen Type X / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D004195:Disease Models, Animal; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D055428:Growth Differentiation Factor 5 / Q000235:genetics / Q000502:physiology; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics / Q000502:physiology; D006984:Hypertrophy / Q000235:genetics; D010003:Osteoarthritis / Q000235:genetics* / Q000503:physiopathology*; D044162:Parathyroid Hormone-Related Protein / Q000235:genetics / Q000502:physiology; D015027:Zebrafish / Q000196:embryology / Q000235:genetics* / Q000502:physiology*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology
chemical_list: D024043:Collagen Type II; D024081:Collagen Type IX; D024121:Collagen Type X; C107966:GDF5 protein, zebrafish; D055428:Growth Differentiation Factor 5; D020662:Guanine Nucleotide Exchange Factors; D044162:Parathyroid Hormone-Related Protein; D029961:Zebrafish Proteins