A HindIII BAC library construction of Mesobuthus martensii Karsch (Scorpiones:Buthidae): An important genetic resource for comparative genomics and phylogenetic analysis
A HindIII BAC library construction of Mesobuthus martensii Karsch (Scorpiones:Buthidae): An important genetic resource for comparative genomics and phylogenetic analysis
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DOI：
10.1266/ggs.84.417
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发表时间：
2009-12-01
影响因子：
1.1
通讯作者：
Li, Wenxin
中科院分区：
文献类型：
--
作者：
Li, Songryong;Ma, Yibao;Li, Wenxin
蝎子是“活的但复杂的化石”，自从4.5亿年前首次出现以来，它们的形态几乎没有变化。为了给了解蝎基因组的进化以及蝎与其他生物的关系提供遗传资源，我们首先测定了蝎目中钳蝎Mesobuthus martensii Karsch的基因组大小（约600 Mbp），并构建了雄性蝎Mesobuthus martensii的HindIII BAC文库。产于中国的martensii Karsch。BAC文库由总共46，080个克隆组成，平均插入片段大小为100 kb，提供了本研究中显示的600 Mbp蝎单倍体基因组大小的7.7倍覆盖率。利用18 S-5.8S-28 S rRNA基因进行高密度菌落杂交文库筛选，该基因是最常用的系统发育标记之一。文库筛选和PCR鉴定结果均显示6个BAC阳性克隆，它们重叠在一起，形成一个约120 kb的重叠群覆盖rDNA。BAC DNA测序分析确定了M.结果表明，该序列包含1813 bp的18 s rDNA、157 bp的5.8s rDNA、3823 bp的28 s rDNA、530 bp的ETS、2168 bp的ITS 1和288 bp的ITS 2。有趣的是，一些串联重复序列存在于rRNA基因间序列（IGS）和ITS 1/2区域。这些结果表明蝎M.马氏马氏链霉菌（martensii Karsch）的rDNA序列及rDNA全序列的测定，为比较基因组学和系统发育分析提供了重要的遗传资源和工具。
Scorpions are "living but sophisticated fossils" that have changed little in their morphology since their first appearance over the past 450 million years ago. To provide a genetic resource for understanding the evolution of scorpion genome and the relationships between scorpions and other organisms, we first determined the genome size of the scorpion Mesobuthus martensii Karsch (about 600 Mbp) in the order Scorpiones and constructed a HindIII BAC library of the male scorpion M. martensii Karsch from China. The BAC library consists of a total of 46,080 clones with an average insert size of 100 kb, providing a 7.7-fold coverage of the scorpion haploid genome size of 600 Mbp as revealed in this study. High-density colony hybridization-based library screening was performed using 18S-5.8S-28S rRNA gene that is one of the most commonly used phylogenetic markers. Both library screening and PCR identification results revealed six positive BAC clones which were overlapped, and formed a contig of approximately 120 kb covering the rDNA. BAC DNA sequencing analysis determined the complete sequence of M. martensii Karsch rDNA unit that has a total length of 8779 bp, including 1813 bp 18s rDNA, 157 bp 5.8s rDNA, 3823 bp 28s rDNA, 530 bp ETS, 2168 bp ITS1 and 288 bp ITS2. Interestingly, some tandem repeats are present in the rRNA intergenic sequence (IGS) and ITS1/2 regions. These results demonstrated that the BAC library of the scorpion M. martensii Karsch and the complete sequence of rDNA unit will provide important genetic resources and tools for comparative genomics and phylogenetic analysis.