Type II collagen is a major component of cartilage providing structural integrity to the tissue. Type II procollagen can be expressed in two forms by differential splicing of the primary gene transcript. The two mRNAs either include (type IIA) or exclude (type IIB) an exon (exon 2) encoding the major portion of the amino (NH2)-propeptide (Ryan, M. C., and L. J. Sandell. 1990. J. Biol. Chem. 265...

In previous studies were have reported on the secretion and extracellular deposition of type II collagen and fibronectin (Dessau et al., 1978, J. Cell Biol., 79:342-355) and chondroitin sulfate proteoglycan (CSPG) (Vertel and Dorfman, 1979, Proc. Natl. Acad. Sci. U. S. A. 76:1261-1264) in chondrocyte cultures. This study describes a combined effort to compare sequence and pattern of secretion a...

In the developing chick embryo tibia type X collagen is synthesized by chondrocytes from regions of hypertrophy and not by chondrocytes from other regions (Capasso, O., G. Tajana, and R. Cancedda, 1984, Mol. Cell. Biol. 4:1163-1168; Schmid, T. M., and T. F. Linsenmayer, 1985, Dev. Biol. 107:375381). To investigate further the relationship between differentiation of endochondral chondrocytes and...

PURPOSE The primary stroma of the developing avian cornea is a highly organized extracellular matrix composed largely of striated collagen fibrils synthesized by the epithelium. These fibrils are heterotypic structures consisting of at least two different fibrillar collagen types (I and II) and probably a fibril-associated collagen (type IX). The epithelial derivation and vectorial secretion of...

Proteoglycan synthesis is dependent on N-acetyl glucosamine (GlcNAc) produced by the hexosamine biosynthetic pathway or obtained exogenously. Although used therapeutically to relieve symptoms of osteoarthritis, the actions of glucosamine and its analogs on cartilage are poorly understood. The purpose of this study was to determine the effects on chondrocytes of N-acylated-glucosamine analogs be...

Crude preparations of lysyl hydroxylase were extracted from chick-embryo tendons synthesizing exclusively type I collagen, chick-embryo sterna synthesizing exclusively type II collagen and HT-1080 sarcoma cells synthesizing exclusively type IV collagen. No differences were found in the Km values for Fe2+, 2-oxoglutarate and ascorbate between these three enzymes preparations. Similarly no differ...