钙反应性反式激活因子在肌萎缩侧索硬化症转基因鼠中的表达及意义

Expression of calcium-responsive transactivator in ALS transgenic mice

目的探讨钙反应性反式激活因子(CREST)在肌萎缩侧索硬化症(ALS)转基因鼠脊髓及脑干组织中的表达变化及相关性作用。方法分别取出生后95 d、108 d、122 d(早、中、晚期)野生型与SOD1-G93A转基因鼠,通过RT-PCR、蛋白免疫印迹技术检测脊髓组织中CREST mRNA及蛋白水平表达变化,通过免疫荧光双标记技术检测脊髓及脑干组织中CREST的表达变化及与神经元及星形胶质细胞的共表达情况。结果 (1)与野生型鼠相比较,SOD1-G93A转基因鼠脊髓组织中CREST蛋白水平下调(P<0.05),在mRNA水平变化并不明显。(2)免疫荧光双标检测显示,CREST主要表达于细胞核,与神经元有共表达,与星形胶质细胞不存在共表达;与野生型鼠比较,SOD1-G93A转基因鼠脊髓和脑干组织中CREST表达下调(P<0.05)。结论 CREST的差异表达可能与ALS运动神经元的功能障碍有关。

Objective To investigate the expression of calcium-responsive transactivator（ CREST） in the spinal cord and brainstem of ALS transgenic mice,and explore the role and significance of CREST in the pathogenesis of ALS. Methods The mRNA and protein level of CREST were detected by RT-PCR and Western blot in the spinal cord of ALS transgenic mice at the different stages of disease（ post-natal 95 d,108 d and 122 d）. The immunofluorescence was used to detect the coexpression of CREST/β-tubulin III and CREST/GFAP in the spinal cord and brain stem.Results Compared with that of wild type mice,the protein level of CREST in the spinal cord tissue was down-regulated（ P〈0. 05）,but not significant at mRNA level. CREST was mainly expressed in the nucleus. CREST-positive cells were also β-tubulin III positive but GFAP negative. Compared with that of wild-type mice,CREST level of SOD1-G93 A transgenic mice in the spinal cord and brain stem was downregulated（ P〈0.05）.Conclusions The differential expression of CREST may be related to the dysfunction of motor neurons in ALS.