Type X collagen

The NCI domain of type VIII collagen is important for trimerization. ACRP30/adiponectin, a member of the complement Clq family of proteins,and the type X collagen NCI domain have similar structures as the NCI domain of type VIII collagen however, the type Vlll collagen NCI trimer lacks the buried calcium cluster found in the type X collagen NCI trimer. The crystal structure of this domain has similarity to the TNF (tumor necrosis factor) family of proteins (PDB accession number 1091). ... 

From recent reports of the mouse model smdies, type X collagen might have an important role not only in growth plate but also in bone marrow fiinctions. " ... 

Type X collagen has a single al chain, which contains a short collagenous domain of 460 residues, flanked by an N-terminal NC domain of 37 residues and C-terminal NC domain of 161 residues." Its protomer is a homotrimer. The C-terminal NC domain is responsible for trimerization and multimer formation, which is based on experiments with recombinant domains." The crystal structure of type X collagen trimerization domain is similar to that of type VIII collagen (see also Section 5.16.6.5). 

Nucleation of calcium phosphate precipitation within the matrix vesicles is mediated by phosphatidylserine, which comprises about 8% of the phospholipids of the inner cytosolic membrane surface (Fig. 9.5a). Calbindin in the vesicle (Fig. 9.5b) may also contribute. Rapid mineral growth within the vesicle keeps the concentration of dissolved calcium and inorganic phosphate ions so low that additional Ca2+ and Pi ions spontaneously enter from the extracellular fluid via their respective transporters. Attached type II and type X collagens from cartilage in the growth plate enhance calcium ion transport and calcification during endochondral ossification (Fig. 9.5b). 

Ninomiya, Y., Gordoa H., van der Rest, M., Schmid, T., Linsenmayer, T. Olsen, B.R. (1986). The developmentally regulated Type X collagen gene contains a long open reading frame without introns./. Biol Chem., 261,5041-50. 

Figure 8.3 Natural (a, b) and synthetic (c, d) nanopattems that offer templates for MSC differentiation and self-renewal (a) Type X collagen and (b) fenestrated sinusoidal capillaries, (c) dip-pen patterned nanoislands (70 nm diameter with 28 mn center-center spacing) that retain MSC multipotency, and (d) self-assembled helical amphiphUe with 63 nm periodicity that stimulates MSC osteogenesis.

Nelea V, Luo L, Demers CN, Antoniou J, Petit A, Lerouge S, et al. Selective inhibition of type X collagen expression in human mesenchymal stem cell differentiation on polymer substrates surface-modified by glow discharge plasma. J Biomed Mater Res A... 

Leboy, P. S., Vaias, L., Uschmann, B., Golub, E., Adams, S. L., and Pacifici, M., 1989, Ascorbic acid induces alkaline phosphatase type X collagen, and calcium deposition in cultured chick chondrocytes, J. Biol. Chem. 264 17281-17286. 

Linsenmayer, T.F., Eavey, R.D., and Schmid, T.M., Type X collagen a hypertrophic cartilage-specific molecule, Pathol. Immunopathol. Res. 7,14-19,1988. 

Gibson, G. et al. Type X collagen is colocalized with a proteoglycan epitope to form distinct morphological structures in bovine growth cartilage. Bone 19, 307,1996. 

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