Skeletal abnormalities and ultrastructural changes of cartilage in transgenic mice expressing a collagen II gene (COL2A1) with a Cys for Arg-α1-519 substitution
Skeletal abnormalities and ultrastructural changes of cartilage in transgenic mice expressing a collagen II gene (COL2A1) with a Cys for Arg-α1-519 substitution
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DOI：
10.1053/joca.2002.0830
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发表时间：
2002-10-01
影响因子：
7
通讯作者：
Fertala, A
中科院分区：
文献类型：
--
作者：
Arita, M;Li, SW;Fertala, A
目的：利用表达人COL2A1突变的转基因小鼠，探讨Arg- >Cys 519突变引起临床表型的机制。方法：从患有原发性广泛性骨关节炎（OA）并伴有轻度软骨发育不良的先证者的成纤维细胞中分离的基因组DNA制备了一个受COL2A1特异性启动子控制的DNA构建体。将构建体注射到FVB/N近交系小鼠受精卵前核中获得转基因小鼠。携带人类COL2A1突变的两个等位基因的转基因小鼠进行了形态学异常和骨骼发育改变的检查。超微结构观察转基因小鼠关节软骨中II型胶原原纤维组织和密度的变化。结果：携带两个突变人胶原基因等位基因的转基因小鼠比正常窝鼠体型小，腭裂，生长板紊乱。关节软骨电镜显示II型胶原原纤维密度降低，软骨细胞呈高尔基体扩张。结论：在转基因小鼠中表达具有Arg- >Cys 519取代的COL2A1导致骨骼发育迟缓和关节软骨超微结构改变，并导致组织中II型胶原原纤维密度的显著降低。这些改变可能是COL2A1突变患者表现出的早发性全身性骨关节炎和软骨发育不良表型的原因。(C) 2002国际骨关节炎研究学会。Elsevier Science Ltd.出版。版权所有。
Objective: To examine the mechanism by which the Arg-->Cys 519 mutation causes the clinical phenotype employing transgenic mice that express the mutated human COL2A1.Methods: A DNA construct under the control of a COL2A1 specific promoter was prepared from genomic DNA isolated from fibroblasts from the proband with primary generalized osteoarthritis (OA) associated with a mild chondrodysplasia. Transgenic mice were obtained by injection of the constructs into pro-nuclei of fertilized eggs from the FVB/N inbred mouse strain. Transgenic mice harboring two alleles of the mutated human COL2A1 were examined for morphological abnormalities and for alterations of their skeletal development. Ultrastructural examination was performed to identify changes in the organization and density of collagen II fibrils in articular cartilage of the transgenic mice.Results: Transgenic mice harboring two alleles of the mutated human collagen gene were smaller than their normal littermates, had a cleft palate, and disorganized growth plate. Electron microscopy of articular cartilage showed a decreased density of collagen II fibrils and revealed chondrocytes with dilated Golgi cysternae.Conclusions: Expression of a COL2A1 with an Arg-->Cys 519 substitution in transgenic mice causes retardation of skeletal development and ultrastructural alterations in articular cartilage with a profound reduction of the density of the collagen II fibrils in the tissue. These alterations may be responsible for the phenotype of precocious generalized OA and chondrodysplasia displayed by patients harboring this COL2A1 mutation. (C) 2002 OsteoArthritis Research Society International. Published by Elsevier Science Ltd. All rights reserved.