作　　者： ; ; ; ; ; ; ;

机构地区： 中南大学湘雅医学院分子生物学研究中心

出　　处： 《Acta Genetica Sinica》 2003年第6期540-546,共7页

摘　　要： 根据东方田鼠基因组DNA序列片段 (GenBank登录号 :AF2 77394 ) ,通过PCR方法扩增东方田鼠长江亚种(Microtusfortiscalamorum)和宁夏指名亚种 (Microtusfortisfortis)基因组DNA ,得到一 6 70bp左右的特异扩增片段。将PCR扩增产物克隆到pGEM Teasy载体 ,进行DNA序列分析 ,并用生物信息学方法比较东方田鼠长江亚种与指名亚种之间该序列的差异。结果表明 :在东方田鼠两个亚种中共发现 19个不同的等位基因 ,不同的个体在该序列存在广泛的单个核苷酸多态性 (SNP) ,多态性位点多达 2 5个 ;变换类型包括 :转换 (G→A、A→G、T→C、C→T)、颠换 (G→T、A→T、T→A、C→A)、插入 (CA)和缺失 (TGTTTT)。东方田鼠长江亚种和指名亚种两个种群之间存在明显差别 ,尤其是在 14 6、192、2 2 3、2 2 4、2 35位 ,但两种群间同源性仍高达 98%。同时采用系统发育树 (phylogenetictree)分析方法 ,对两个亚种的亲缘关系进行了分析和比较 ,结果显示 。 Microtus fortis (Taxonomy ID:100897),also named as reed vole,is classified as Microtus,Micotinae ,Cricetidae,Rodentia,Mammalia on taxonomy. Microtus fortis mainly distributes in China.Some areas of Russia,North Korea and Mongolia close to Northeast borderland of China also have a small number of Microtus fortis in distribution. Microtus fortis in China has principally 4 subspecies,and most of them live is the drainage area of Yangtse River. Schistosoma japonicum (one of commonly parasites in China) can infect about 40 kinds of mammalian animals,including the human being,but could not infect Microtus fortis .It is known as the only animal in Dongting Lake region of China which has the ability of natural resistance to Schistosoma japonicum .The Microtus fortis domesticated in laboratory has the same biological characteristics as the wild one and these characteristics could be inherited to its progeny steadily.We got a specific DNA fragment from genomic library of Microtus fortis .This DNA fragment in genomic DNA of human beings,Kunming mice,Balb/c mice and C57BL/6J mice could not be detected by dot blot hybridization and PCR,apart from genomic DNA of Microtus fortis. In this report,the differences of genomic DNA in 34 Microtus fortis were compared between Microtus fortis calamorum (Dongting Lake region of southern China) and Microtus fortis fortis (Ningxia province of northern China).The residing localion of these two subspecies is far away about 1 200 kilometers from each other.The genomic DNA of Microtus fortis calamorum and Microtus fortis fortis were extracted and amplified by PCR according to the specific genomic DNAs sequence of Microtus fortis reported previously (Accession number in GenBank:AF277394).The amplified DNA fragments were inserted into pGEM T easy vector and sequenced.The DNA fragment sequencing results from the two subspecies were compared to detect whether there was any difference.19 alleles were found from Microtus fortis (20 of Mic

关 键 词： 东方田鼠 生物进化

领　　域： [生物学]