大鼠类Alu重复序列的克隆及其在染色体DNA突变分析中的应用

CLONING OF AN ALU LIKE SEQUENCE FROM RAT LOW COT DNA LIBRARY AND ITS APPLICATION IN THE ANALYSIS OF GENOMIC DNA MUTATION

从大鼠低Cot值DNA文库分离到一种类Alu的重复序列 ,命名为RALRS 1.对RALRS 1克隆并进行了测序 ,长度为 2 83bp ,发现其中含有单一的微卫星 (microsatellite)序列AG ,AGG和AGGG .RALRS 1DNA序列在大鼠单倍体基因组中的拷贝数为 15 0 0 0 0～ 330 0 0 0 .依RALRS 1中的一段序列合成了一 2 8寡核苷酸探针 (AGGG) 7,对大鼠正常组织和肿瘤组织DNA指纹谱分析时 ,不但能显示活动清晰的指纹谱带型 ,并能显示与正常组织间所存在的区别 .本研究证明我们所发展的方法能够快速而方便地获得同源重复序列探针 ,用于DNA指纹谱分析 .这类分析对研究基因组的变化提供了有价值的途径 .图 3参

A rat Alu like repetitive sequence (RALRS 1) was cloned from rat low Cot DNA library. The cloned RALRS 1 was sequenced and found to be 283 bp in length containing highly repeated AG, AGG, and AGGG sequences. The copy number of RALRS 1sequence was around 150 000～330 000 per rat haploid genome. A synthesized 28 mer oligo nucleotide probe, e.g. (AGGG) 7 was used in the DNA fingerprinting analysis and resulted in a distinct banding pattern. Additionally, the differences of the banding pattern were seen between normal and tumor tissue in rat. This probe should be useful for the gene mutation caused by various factors in rat. Fig 3, Ref 10