Extensive sequence divergence between the reference genomes of Taraxacum kok-saghyz and Taraxacum mongolicum
Extensive sequence divergence between the reference genomes of Taraxacum kok-saghyz and Taraxacum mongolicum
复制标题
DOI：
10.1007/s11427-021-2033-2
复制
发表时间：
2021-12-17
影响因子：
9.1
通讯作者：
Li, Jiayang
中科院分区：
文献类型：
--
作者：
Lin, Tao;Xu, Xia;Li, Jiayang
蒲公英属植物在世界各地广泛分布，其中包括橡胶生产和非橡胶生产的物种。然而，天然橡胶（NR）生物合成的基因组基础仍然需要更多的调查。在这里，我们提出了高质量的基因组组装的橡胶生产T。kok-saghyz TK 1151和非产胶T.蒙古苜蓿TM 5.比较分析发现了大量的遗传变异，包括倒位，易位，存在/不存在的变化，以及相当大的蛋白质差异之间的两个物种。在这两个蒲公英属物种中发现了两个多倍体化事件，包括一个共同的真双子叶植物的祖先全基因组三倍体和随后的一轮多倍体化。在TK 1151和TM 5的基因组中，我们鉴定了NR生物合成途径中每个步骤的编码基因，并发现SRPP和CPT基因家族在TK 1151中比在TM 5中经历了更明显的扩增。本研究对NR生物合成机理的研究和NR作物的遗传改良具有重要意义。
Plants belonging to the genus Taraxacum are widespread all over the world, which contain rubber-producing and non-rubber-producing species. However, the genomic basis underlying natural rubber (NR) biosynthesis still needs more investigation. Here, we presented high-quality genome assemblies of rubber-producing T. kok-saghyz TK1151 and non-rubber-producing T. mongolicum TM5. Comparative analyses uncovered a large number of genetic variations, including inversions, translocations, presence/absence variations, as well as considerable protein divergences between the two species. Two polyploidization events were found in these two Taraxacum species, including one common ancestral whole-genome triplication of the Eudicots and one subsequent round of polyploidization. In genomes of both TK1151 and TM5, we identified the genes encoding for each step in the NR biosynthesis pathway and found that the SRPP and CPT gene families have experienced a more obvious expansion in TK1151 compared to TM5. This study will have large-ranging implications for the mechanism of NR biosynthesis and genetic improvement of NR-producing crops.