【摘要】 目的:对一个肌萎缩侧索硬化症(Amyotrophic lateral sclerosis,ALS)家系的突变铜、锌超氧化物歧化酶(Cu/Zn su-peroxide dismutase,SOD1)基因进行研究,了解其与野生型SOD1在不同部位神经组织中表达的差异性。采用软件进行模建,对突变SOD1蛋白质的二、三级结构进行预测和分析。方法:采用Northern杂交对突变SOD1 mRNA进行分析;克隆出突变SOD1 cD-NA和野生型SOD1 cDNA,采用含有人多种神经组织mRNA的预制Northern杂交膜,了解突变SOD1与野生型SOD1在不同部位神经组织中表达的差异性;采用软件对突变蛋白质的二、三级结构进行模建分析。结果:Northern blot分析证实2号外显子mRNA缩短。野生型和突变的SOD1基因具有相似的组织表达差异性,在大脑皮层表达最高,在脊髓表达最弱。突变后的SOD1蛋白质二级、三级结构与野生型SOD1基本相似。结论:突变后SOD1酶活性的功能下降可能是引起该家系发病的原因,SOD1基因在不同神经组织表达的差异性,可能是该家系ALS患者临床表现以下运动神经元损害为主的原因。更多还原

【Abstract】 Objective: The Northern hybrid membrane containing kinds of human brain tissues was used to study the mutational Cu/Zn superoxide dismutase(SOD1) gene and variabilities of expression in the brain.To predict the secondary and tertiary structure of mutant protein with modeling system.Methods:Expressions of SOD1 were performed by Northern hybridization.To clone mSOD1 cDNA and wild-type SOD1 cDNA with RT-PCR and study the variabilities of the expression in the brain.Secondary and tertiary structure of mutant protein were predicted and analyzied with modeling system.Results:Norhtern hybridization confirmed the mutant SOD1 is composed of 35 amino acid residues,and show a beta-folding structure.Norhtern hybridization confirmed that expression of both mutational and wild-type SOD1 was similar,the highest in cerebral cortex,next in medulla,the poorest in spinal cord.Conclusions:The decrease of enzyme activity of mutational SOD1 protein may be related to etiological factor of the FALS.SOD1 gene expressed differentially in kinds of brain tissue may be responsible for the clinical manifestation of the FALS and lower motoneurons damage is the major sign.更多还原