tissues by Northern and in situ h cDNA Virpi Glumoff, Mikko Savontal University of Turku, Departments of Molecular Biolo, Received : ract artilage matrix is an interacting multicomponent system c oglycans and glycoproteins entrapped within the fibrillar ne :ent components we have constructed short cDNA clones for c age matrix, aggrecan and tenascin. We subsequently determine RNAs isolated from several newborn mouse tissues. The exp A was present at variable levels in most of the tissues studied .,can and tenascin production in newborn mouse tissues by in sJ :trocytes throughout the developing skeleton in a pattern very s lewborn mouse skeleton tenascin and aggrecan mRNAs w~ :riots bein~ oresent in osteoblasts. Deriosteal and oerichondria of collagen fibrils, fibril-associ network. In order to better under clones for detection of mRNAs for two maj determined their corresponding mRNA le' ~ression of aggrecan was strictly studied. The cDNA clones were also us y in situ hybridization. With this techr similar but not identical to those were expressed essentially in a ~blasts, periosteal and perichondrial cells, and in cells at articular s • aggrecan genes. The results further suggest different patterns of cartilages. lagen; Development; Proteoglycan; Skeleton; Tenascin; (Mouse) teoglycan (aggrecan) m protein contains several f cartilage forms a multicom- sulphate chains, as well :ollagen fibrils, proteoglycans rides [3]. The glycosami tgen fibrils are composed of 80-90% of the molecul~ I and type XI collagen with huge macromolecular n and two other small proteo- where several aggrecan iodulin located on the fibril molecule with the help hin the network of collagen aggregates are highly h ing chondroitin sulphate pro- with resilience. The str~ cribed to the collagen t glycoproteins of cartilagq proteo different com cartila total mRNA aggrecan chondroc the newborn transcripts g present in osteoblasts the cartilage specific collagen or on their location in the different Keywords: Aggrecan; Cartilage; Collagen; 1. Introduction The extracellular matrix of ponent system consisting of colla and glycoproteins. The colla rod-like molecules of type II type IX collagen-proteoglycan and glycans, decorin and fibromc surface [1,2]. Entrapped within fibrils are the large aggregating e The nucleotide sequence data reported deposited to the EMBL/GenBank data bases sion numbers: human aggrecan cDNA, X8027 YR(19"]Q- hllm~n t~n~pln rFI1~JA YRNgRN. m~,¢ Biochimica et Biophysica Acta 1219 (199L can and tenascin gene hybridi probe Savontaus, Jann ~gyand MedJ Received 22 April 19(~ Bioch et Bio~ sion in mouse s] asing species sp, n, Eero Vuorio * "y, FIN-20520 Turku, Finland il-associated small proteoglyq understand the relationship jor noncollagenous ma levels by Northern analy restricted to cartilage used to identify the celk, s technique aggrecan mRNA of type II and IX coll~ mutually exclusive n surfaces. None of these gene expression in cho molecules. A single chondroitin sulphal as N- and O-linke, cosamlnoglycan side chain ecular mass of aggrecan. aggregate (M r -- 10 molecules bind to of specific link p ydrated which pro~ structural strength of c fibrils. The functior Lge matrix are poorly primary structure of aggr~ !50 kDa) has been deduce led for rat [4], human [5] hree aggrecan mRNAs hax alternative splicing of the