【摘要】 根据生物素与链亲和素的强亲和性原理 ,用链亲和素磁珠亲和捕捉与生物素标记的微卫星寡核苷酸探针(CA) 12 、(CCG) 8、(CAG) 8、(TTTC) 8退火结合的含有接头和牦牛微卫星序列的单链限制性酶切片段 ,获得单链目的片段 ,经PCR扩增形成双链 ,然后克隆到pMD18 T载体上 ,转化至DH5α中 ,首次成功构建牦牛基因组微卫星富集文库。测序结果发现 ,阳性克隆率为 77% (37/ 4 8) ,说明构建的牦牛基因组微卫星富集文库是一个高质量的文库。牦牛富集微卫星文库的建立和牦牛微卫星的筛选将为下一步进行牦牛基因组结构的分析、牦牛遗传连锁图谱的构建、分子进化和系统发育研究、标记辅助选择以及经济性状的QTL定位提供大量的微卫星标记。更多还原

【Abstract】 We constructed the first microsatellite-enriched library of yak according to the strong affinity between biotin and streptavidin.The method included ligation of 300～1 000 bp enzyme-digested fragments and adaptors,affinity capture of microsatellite repeat using biotinylated oligoprobe(（CA）₁₂,（CCG）₈,（CAG）₈,（TTTC）₈) attached to streptavidin-coated magnetic beads,PCR amplification using the 21-mer adaptor oligonucleotide as primer to obtain double-stranded targeted fragments,religated into pMD18-T vector and transformed to DH5α.The results of sequencing showed that 37 of 48 readable sequences contained microsatellites indicating a high degree of microsatellite enrichment.The new polymorphic microsatellite markers we have identified and characterized will contribute to the yak genetic linkage mapping,molecular evolution and phylogenetic studies,marker assistant selection and QTLs location of yak main economic traits.更多还原