新方法實現多倍體植物基因組的全染色體組裝
作者:
小柯機器人發布時間:2020/11/4 16:53:45
澳大利亞昆士蘭大學Lachlan J. M. Coin課題組利用新方法實現多倍體植物基因組的全染色體組裝。相關論文於2020年10月30日發表在《自然—遺傳學》雜誌上。
研究人員報導了通過遺傳連鎖分析將重疊群分組和排序為假分子的PolyGembler方法。這個方法還提供了一種檢測和修復裝配錯誤的準確方法。使用模擬數據,研究人員證明了該方法具有很高的準確性,並且優於三種現有的最新遺傳作圖工具。特別是對於缺少基因型數據和基因分型錯誤的情況,這個方法更加穩健。
研究人員利用PacBio長讀與限制性位點相關DNA測序相結合的方法,為異源四倍體草坪植物構建了假分子;利用Illumina讀本組裝的重疊群與單核苷酸多態性產生的基因型數據相結合,分別通過測序和基因分型構建了二倍體番薯和三倍體馬鈴薯。研究人員解決了已發表的 I. trifida 基因組組裝的13個裝配錯誤,並在已發表的馬鈴薯基因組中確定了八個未確定的框架。
據了解,儘管測序技術取得了進步,但由於多倍性和高重複含量,複雜植物基因組的組裝仍然難以實現。
附:英文原文
Title: Assembly of whole-chromosome pseudomolecules for polyploid plant genomes using outbred mapping populations
Author: Chenxi Zhou, Bode Olukolu, Dorcus C. Gemenet, Shan Wu, Wolfgang Gruneberg, Minh Duc Cao, Zhangjun Fei, Zhao-Bang Zeng, Andrew W. George, Awais Khan, G. Craig Yencho, Lachlan J. M. Coin
Issue&Volume: 2020-10-30
Abstract: Despite advances in sequencing technologies, assembly of complex plant genomes remains elusive due to polyploidy and high repeat content. Here we report PolyGembler for grouping and ordering contigs into pseudomolecules by genetic linkage analysis. Our approach also provides an accurate method with which to detect and fix assembly errors. Using simulated data, we demonstrate that our approach is of high accuracy and outperforms three existing state-of-the-art genetic mapping tools. Particularly, our approach is more robust to the presence of missing genotype data and genotyping errors. We used our method to construct pseudomolecules for allotetraploid lawn grass utilizing PacBio long reads in combination with restriction site-associated DNA sequencing, and for diploid Ipomoea trifida and autotetraploid potato utilizing contigs assembled from Illumina reads in combination with genotype data generated by single-nucleotide polymorphism arrays and genotyping by sequencing, respectively. We resolved 13 assembly errors for a published I. trifida genome assembly and anchored eight unplaced scaffolds in the published potato genome. PolyGembler, a method for grouping and ordering contigs into complete pseudomolecules by combining long-read sequencing and genotype information from an outbred mapping population, improves the accuracy for assembly of polyploidy plant genomes.
DOI: 10.1038/s41588-020-00717-7
Source: https://www.nature.com/articles/s41588-020-00717-7