波形纤维蛋白转基因白内障小鼠晶状体超微结构的研究

Ultrastructural observation of the cataractous lens in vimentin transgenic mice

目的 :观察波形纤维蛋白转基因小鼠 (下称 VTg M)白内障晶状体的超微结构变化。方法 :用微注射法将鸡的波形纤维蛋白基因导入小鼠的受精卵中 ,获得 2 0只白内障小鼠。应用超薄切片透射电镜技术 ,观察 VTg M晶状体的超微结构改变。结果 :VTg M晶状体上皮细胞呈多层排列 ,细胞内有粗大的线粒体 ,晶状体皮质内有核细胞成团堆集 ,胞浆内有大量细胞器 ,特别是线粒体、溶酶体。晶体状纤维细胞排列紊乱 ,核伸长不完全。纤维的规则板层结构消失 ,出现大量的髓鞘样结构。结论 :外源性波形纤维蛋白的表达影响了晶状体上皮细胞的分化 ,使晶状体纤维细胞脱核 ,脱细胞器受抑制 ,晶状体纤维排列紊乱 。

Purpose:To observe the ultrastructural changes of the cataractous lens in vimentin transgenic mice.Methods:12.7kb chicken vimentin genes were microinjected into the male pronuclei of ICR mice.The injected embryos were transferred to the pseudopregnant recipient females and were generated several transgenic mice.The cataractous transgenic mice strains were established by crossbreeding.Twenty mice developed cataract.Two cataractous lensees and two normal lenses were taken and the lens ultrastructures were observed with transmission electron microscope.Results:Many large mitochondria were observed in the epithelial cells of the cataractous lens.In the cortex of these lenses,there were accumulated nuclei and abounded organelles.Arrangement of fiber cells was irregular,enlongation of the nuclei was insufficient and nuclei were undecleated.Numerous myelin figures were seen in the cortex.Conclusion:These results show that over expressed vimentin gene influences the differentiation of the epithelial cells.Degradation of nuclei and all membrane\|bound organelles is inhibited.Distribution of the lens fibers is irregular.These changes result in cataract formation in vimentin transgenic mice.