蓝狐-卫星DNA的克隆及序列分析

利用限制性内切酶酶切蓝狐基因组, 经琼脂糖凝胶电泳, 对特异性亮带进行克隆、测序及序列分析。结果获得42个卫星DNA序列, 该卫星DNA单体大小为737 bp, G+C含量为51.9%, 单体之间同源性为91%~97%; 每个单体由3个约245 bp的亚重复串联构成, 亚重复之间的同源性为49%~55%; 在物种进化过程中, 该卫星DNA有G+C含量逐渐降低而A+T含量逐渐上升的趋势; 该卫星DNA为犬科动物种属所特有, 与犬着丝粒相关卫星DNA为同类卫星DNA, 同源性为74%, 命名为α-卫星DNA。

Cloning and sequence analysis of alpha satellite DNA in arctic fox

Genomic DNAs from Arctic fox were cleaved with restriction enzymes.The prominent ethidium-bromide stanined bands were cloned and sequenced after separation of DNA fragments by agarose gel electrophoresis.Forty-two satellite sequences were obtained by sequencing.Sequence analyses revealed that the satellite monomer in length was 737 bp,with an average G C content of 51.9%.There were 91%-97% homology among the monomers,and the monomer con-sisted of three subrepeats of approximately 245 bp in length with 51%-54% homology.The satellite DNAs were specific for Canidae,and had 74% homology to the dog centromere-associated nucleotide sequences.In order to distinguish from another satellite DNAs of canidae genome,the satellite was designated as alpha satellite DNA.