Chains of matrix-derived type X collagen: size and aggregation properties.

Type X collagen was isolated from extracts of embryonic chick cartilages by immunoprecipitation and subsequently analyzed by SDS-PAGE. Most of the chains migrated with a molecular weight of 59 kDa, suggesting that the matrix form of type X collagen has not undergone post-secretory proteolytic processing. Minor amounts of material were also observed at 120 kDa, 70 kDa and 50 kDa. These were dimers or limited proteolytic products of type X chains.