中国桑属15个种RAD-seq高通量测序

RAD-seq High-Throughput Sequencing of 15 Species of Morus

利用RAD-seq对中国桑属15个种进行了高通量测序,总共得到36.72Gb clean data,总Tags数2 788 927(reads),平均每个种原始数据都在10M以上,Tags都在20万条以上,质量值Q30都在90%以上。用Stacks软件对15个种进行比对,获得68904个SNPs位点。用最大似然法建树,分支图首先将白桑、广东桑分出,接着是山桑、鲁桑、瑞穗桑,再次分出的是鸡桑、细齿桑、蒙桑和鬼桑,最后分出的是黑桑、川桑、华桑、滇桑、长穗桑、奶桑。分支图能将栽培种和野生种完全分开;可以将蒙桑和鬼桑、鸡桑、华桑、川桑、奶桑分开。认为白桑、广东桑属原始类型,长穗桑、奶桑属进化类型;山桑、鲁桑、瑞穗桑这三个种被分在一个分支,自检支持率99%,黑桑、川桑这两个种被分在一个分支,自检支持率56%,长穗桑、奶桑这两个种被分在一个分支,自检支持率100%,说明这些种之间有较近的亲缘关系,桑属RAD-seq测序能大规模筛查SNPs位点,系统发育分析的准确性就更加可靠。

In this study, RAD-seq （restriction site-associated DNA sequencing） was performed toidentify the SNP loci between 15 species of the genus Morus. A total of 36.72 Gb clean data were sequenced by Illumina hiseq 4000 and a total of 68904 SNP loci were obtained by Stacks software. The data sets were analysed using the maximum-likelihood method. The cultivated and wild species were completely separate, M. alba and M. atropurpurea were original genera of mulberry, however, M. wittiorum and M. macroura were of the evolutionary type. M. serrata, M. mongolica, and M. mongolica var. diabolica had close genetic relationship, while M. yunnanensis, M. wittiorurn and M. macroura had close genetic rela- tionship. Analyses based on these RAD tags yielded robust phylogenetic inferences, even with data set constructed from surprisingly few loci. The study illustrates the potential for resolving difficult phylogenetic relationships in genus Morus.