Identification of Genes Preferentially Expressed in Articular Cartilage by Suppression Subtractive Hybridization

Suppression subtractive hybridization is veryeffective to enrich differentially expressed genes intwo different tissues or cells. We therefore used thetechnique to identify characteristic genesexpressed in rat knee joint articular cartilage ascompared to rat costal cartilage. In this study, werevealed that several genes were enriched in a subtractedarticular cartilage cDNA library. The mostenriched gene is lubricin that is a putative key moleculefor joint lubrication. The second gene ismilk fat globule epidermal growth factor (EGF)factor 8, MFG-E8 whose expression has neverbeen observed in cartilage. Other enriched genesare known to be expressed in cartilage, howevertheir differential expressions in cartilages havenot been necessarily common. The preferentialexpression of characteristic genes in articularcartilage would provide unique properties to the tissue.Our findings will provide a new view of articularcartilage.