复合杂合性CCN6基因突变致晚发型脊柱骨骺发育不良伴进行性骨关节病的关节软骨病理和分子病因研究  

Pathology and molecular pathogenesis of spondyloepiphyseal dysplasia tarda with progressive arthropathy caused by compound CCN6 heterogeneous gene mutations

作　　者：彭依群[1] 廖二元[1] 顾慧敏[1] 魏启幼[2] 周厚德[1] 李剑[2] 谢辉[1] 翟木绪[1] 谭利华[3] 罗湘杭[1] 伍贤平[1] 胡平安[1] 倪江东[4] 苏欣[1] 蒋谊[2] 戴如春[1] 郭丽娟[1] 袁凌青[1] 王敏[1] 王平芳[1] 刘石平[1] 杨雅[1] 王成[1] 隋国良[1] 方团育[1] 

机构地区：[1]中南大学湘雅二医院代谢内分泌研究所,长沙410011 [2]中南大学湘雅二医院病理科,长沙410011 [3]中南大学湘雅二医院放射科,长沙410011 [4]中南大学湘雅二医院骨科,长沙410011

出　　处：《中华医学杂志》2004年第21期1796-1803,共8页National Medical Journal of China

基　　金：国家"九五"攻关基金资助项目 ( 9690 60 5 0 5 );国家自然科学基金资助项目 ( 3 9970 3 47)

摘　　要：目的　观察晚发型脊柱骨骺发育不良伴进行性骨关节病 (SEDT PA)患者的X线及磁共振成像特点、关节软骨病理特点 ,筛查CCN6基因突变位点 ,探讨SEDT PA的发病机制。方法　应用放射学、磁共振成像方法分析汉族家系中两例SEDT PA患者骨骼及软骨等结构特点 ;应用HE和甲苯胺蓝染色法对关节软骨进行组织病理学特点观察 ;用电子显微镜观察关节软骨组织和细胞的超微结构 ;设计引物对CCN6基因外显子进行扩增和测序分析 ;应用突变CCN6蛋白质三维结构预测等方法研究SEDT PA的发病机制。结果　病理检查发现汉族家系中一例SEDT PA关节软骨细胞增生活跃伴成熟障碍 ,而基质胶原纤维大小和密度明显下降。突变筛查提示两患者在CCN6基因 8号外显子存在两种突变类型 ,其中的替换突变 (10 0 0T→C ,Ser334Pro)来自父方 ;而缺失突变(84 0delT)来自母方 ,导致其编码的氨基酸序列移码突变 ,在下游 31个氨基酸残基后提前出现终止密码子 ,导致蛋白质被截短 4 3个氨基酸残基。蛋白质三维结构预测结果显示 84 0delT截短突变蛋白质与野生型蛋白质相比 ,从信号肽至第一个结构域 (IGFBP)起始的 2 4个氨基酸残基区域由一个单一环变成两个小的交叉环 ,而且伴C末端明显缩短 ,而Ser334Pro蛋白质仅有C末端的延伸方向与野生型蛋白质相反 ,其余?Objective To characterize the clinical manifestations, features of roentgenography and MR imaging, and the pathology of articular cartilage and matrix of spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT PA), to screen the mutations of the disease causing CCN6 gene, and try to elucidate the molecular pathogenesis of SEDT PA. Methods A questionnaire survey on the clinical manifestations and history was conducted among a pedigree of SEDT PA with 57 persons (53 living members) in tolal, including 2 probands, a 19 year old female and a 9 year old male Physical examination and roentgenography and MR imaging were used on the 2 probands to characterize the features of their joints and articular cartilage The femoral head extracted during replacement of hip of the proband 1 underwent hematoxylin eosin staining and toludine blue (TB) staining to observe the pathological changes and ultra microstructure of the articular chondrocytes and cartilage matrix using electron microscopy Peripheral blood samples were collected from these 53 living members and 100 healthy controls PCR was used to examine and sequence the exons of CCN6 3D conformational illustration of mutant CCN6 proteins were predicted using the Prospect Software Results The clinical manifestations, radiology, and MR imaging established the diagnosis of SEDT PA Pathologic examination demonstrated that the articular cartilage chondrocytes became hyper proliferative and immature, while the density and diameter of matrix collagens were dramatically decreased Mutation studies showed the two probands carried a deletion (840delT) mutation in maternal allele, that caused the truncated CCN6 protein to miss 43 residues in C terminus; and a substitution mutation (1000T→C,Ser334Pro) in paternal allele, which was also inherited down to other 4 members in the SEDT PA kindred The predicted 3D conformational changes of the truncated mutant and the Ser334Pro mutant CCN6 proteins demonstrated that in comparison with the wild

关 键 词：关节软骨 患者 进行性 晚发型 骨病 分子病因 脊柱骨骺发育不良 杂合性 蛋白质 野生型 

分 类 号：R684[医药卫生—骨科学]