软骨Ⅹ型胶原研究进展

Advances in the Study of Cartilaginous TypeⅩ Collagen.

软骨Ｘ型胶原是由软骨肥大区细胞特异表达合成的非微纤维形成性胶原，在软骨内骨化过程中发挥着重要的作用，可能与基质降解、钙化、血管侵入有关，文章就其分子特点、基因结构、功能及其与疾病的关系进行综述．

Recent advances in the molecularcharacteristics,gene structure,functions oftype Ⅹ collagen and its relation to diseaseswere introduced.Type Ⅹ collagen consists ofthree identified α peptides and is assigned tothe non-fibril-forming collagen synthesizedprimarily by hypertrophic chondrocyte ingrowth plate cartilage.Complete type Ⅹ col-lagen molecule includes COL,NC_1 and NC_2domains in which COL domain,a main pep-tide,has two cleavage sites sensitive to colla-genase. Short as is its chain, type Ⅹ collagendisplays a very stable property , and its mel-ting temperature is up to 47℃.The gene oftype. Ⅹ collagen,unlike other interstitial col-lagens,is composed of three exons and twointrons,andtheentire COL domain is encodedby a large exon──exon_3 which condenses thegene information. Type Ⅹ collagen plays animportant role during endochondral ossifica-tion and seems to be related to matrix degra-dation , mineralization and/or vascular inva-sion.Distribution and quantity abnormalitiesof type Ⅹ collagen were observed in some os-teoarticular disorders, such as osteoarthritisand rachitis. The mutations of type Ⅹ colla-gen gene coding for NC_1 domain make the mu-tant polypeptides difficultlv associate witheach other , impair supramolecular assemblesand lead to its disfunction in growth cartilage,which appears to elicit given inheritable chon-drodysplasias.