Structural and functional comparison of type IX collagen-proteoglycan from chicken cartilage and vitreous humor.
نویسندگان
چکیده
Type IX collagen-proteoglycan is a major component of hyaline cartilages where it is located on the surface of the collagen fibrils so that a collagenous domain of the molecule (called COL3) and a non-collagenous domain (called NC4) project at periodic distances away from the surface of the fibril. Type IX collagen-proteoglycan is also present on the surface of the collagen fibrils of the adult chicken vitreous but, unlike cartilage, lacks the NC4 domain and possesses a very long chondroitin sulfate chain which provides an extensive coat to the fibril. A monoclonal antibody (called 4D6) is described which will distinguish cartilage from vitreous type IX collagen. To form the epitope for 4D6 two peptides called C2 and C5 derived, respectively, from the alpha 1(IX) and alpha 3(IX) chains are required. Further analysis shows that specificity for 4D6 resides only in the C2 peptide from cartilage and not in C5. These results are entirely consistent with recent evidence that there are two promoters for transcription of the alpha 1(IX) chain which will result in an alpha 1(IX) chain in which the NC4 domain is either present or absent and that expression of these two promoters has tissue specificity (Nishimura, I., Muragaki, Y., and Olsen, B. R. (1989) J. Biol. Chem. 264, 20033-20041). In addition, the function of type IX collagen in cartilage and vitreous may differ with the long chondroitin sulfate chains of vitreous type IX collagen being responsible for the gel-like matrix of this tissue.
منابع مشابه
Occurrence in chick embryo vitreous humor of a type IX collagen proteoglycan with an extraordinarily large chondroitin sulfate chain and short alpha 1 polypeptide.
We have prepared a high buoyant density proteoglycan fraction from the vitreous humor of 13-day-old chick embryos. Using immunoblot analysis coupled with chondroitinase digestion, we demonstrate that the purified preparation is composed predominantly of type IX collagen-like chondroitin sulfate proteoglycan with an alpha 1(IX) chain Mr approximately 23,000 shorter than the known alpha 1 in cart...
متن کاملCollagen type IX from human cartilage: a structural profile of intermolecular cross-linking sites.
Type IX collagen, a quantitatively minor collagenous component of cartilage, is known to be associated with and covalently cross-linked to type II collagen fibrils in chick and bovine cartilage. Type IX collagen molecules have also been shown to form covalent cross-links with each other in bovine cartilage. In the present study we demonstrate by structural analysis and location of cross-linking...
متن کاملThe structure of human collagen type IX and its organization in fetal and infant cartilage fibrils.
Human collagen type IX was isolated from the media of organ cultures of fetal or infant hyaline cartilage. It consisted of three distinct, disulfide-bonded polypeptides of 115, 84, and 72 kDa, respectively. Digestion with chondroitinase ABC reduced the apparent molecular mass of the 115-kDa chain to about 65 kDa demonstrating that also human collagen type IX is a proteoglycan. In the electron m...
متن کاملIsolation and Characterization
Previous studies show that the collagen fibrils of the mammalian vitreous humor are assembled largely from type I1 collagen with smaller amounts of type IX collagen and either type V or type XI collagen. In this paper, we report the separation of two chains of type V/type XI collagen from type I1 collagen by heparinSepharose chromatography. These chains were characterized by sequencing of selec...
متن کاملOpticin binds to heparan and chondroitin sulfate proteoglycans.
PURPOSE The extracellular matrix glycoprotein opticin is a small leucine-rich repeat proteoglycan/protein family member that was discovered associated with vitreous humor collagen fibrils. Opticin is present throughout the vitreous, but is particularly concentrated at the internal limiting lamina, where it colocalizes with type XVIII collagen. The present study investigated whether opticin inte...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 266 8 شماره
صفحات -
تاریخ انتشار 1991