【摘要】 采用PCR和DNA测序技术对4个泥鳅(Misgurnus anguillicaudatus)群体的线粒体DNA控制区序列进行比较,研究其遗传多样性和控制区的结构。结果显示,用于分析的线粒体DNA控制区片段序列为918～920 bp。32个序列中共发现了56个多态位点,其中32个转换位点,19个颠换位点,5个转换与颠换同时存在的位点,定义了32种单倍型。同时对控制区结构进行分析,识别了其终止序列区(ETAS)、中央保守区(CD)和保守序列区(CSB)的关键序列。4个地理群体的单倍型多样性(Hd)、核苷酸多样性(Pi)和平均核苷酸差异数(K)分别为0.992、0.012和10.698。群体间的平均Kimura双参数遗传距离(Kimura 2-parameter distance,K2-P)、遗传分化指数(Fst)、基因交流值(Nm)和分子方差分析(AMOVA)均表明4个泥鳅群体具有较高的遗传分化,基因交流贫乏。利用核苷酸序列构建的NJ分子系统树揭示4个群体分为2个谱系,除范县群体外,其余各群体间相互交叉聚集。更多还原

【Abstract】 We compare and study the genetic diversity and structure of DNA control region of 4 Misgurnus anguillicaudatus populations by using PCR and DNA sequencing.The results show that the sequence of mitochondrial DNA control region is 918~920 bp.Among 32 sequences,a total of 56 polymorphic loci were detected,including 32 transitions,19 transversions,5 transitions-transversions and 36 haplotypes.The key sequences of extended terminal associated sequences(ETAS),central domains(CSB-A,B,C,D,E and F) and conserved sequence blocks(CSB-1,CSB-2 and CSB-3) were discovered.The haplotypic diversity(Hd),average genetic distance(Pi) and average number of pairwise differences(K) is 0.992,0.012 and 10.698,respectively.The average Kimura 2-parameter distance,Fst value,Nm value and AMOVA reveal great genetic differentiation among the 4 M.anguillicaudatus populations.The NJ phylogenetic tree constructed on nucleotide sequence indicates that the 4 populations form into 2 monophyletic lineages,and cross and cluster among one another except Fanxian population.更多还原