Type IX collagen

Mutations in COL9A1, COL9A2, and COL9A3 cause multiple epiphyseal dysplasia (MED), an autosomal dominant chondrodysplasia. Also, mutations in COMP, which interacts with type IX collagen, cause MED. 

Part-time extracellular proteoglycans include variants of well-characterized extracellular glycoproteins such as type IX collagen [141], Clq [142], colony stimulating factor [143], amyloid precursor protein [144], fibronectin [145], and brain-specific receptor-type tyrosine phosphatase (3 [146]. 

Harel, R., Sharma, Y.D., Aguilera, A. et al. (1992). Qoning and developmental expression of the a3-chain of chicken type-IX collagen. ]. Biol. Chetn., 267, 10070-6. 

Nishimura, I., Muragaki, Y. Olsen, B.R. (1989). Tissue-specific forms of type IX collagen-proteoglycan arise from the use of two widely separate promoters. ]. Biol Chem., 264, 20033-41. 

Swiderski, R.E. Solursh, M. (1992b). Differential coexpression of long and short form type IX collagen transcripts during avian limb choixlrogenesis in ovo. Development, 115,169-79. 

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