美国哈佛大学James Mallet和Nathaniel B. Edelman合作发现基因组结构和基因渗入对蝴蝶适应辐射的影响。相关论文发表在11月1日出版的《科学》杂志上。

研究人员利用20个从头开始的基因组组装案例来探究快速辐射的袖蝶属蝴蝶的形成历史和基因流结构。研究人员将不完整谱系排序从基因渗入中区分出来，并证明在广泛的基因组范围内，基因流已掩盖了该群体与几种古老谱系的发育关系。渗入基因座在低重组和基因丰富的区域代表性不足，这与清除和不相容基因座紧密相连的外来等位基因是一致的。

研究人员确定了一个迄今未知的倒置，这种倒置揭示了一个颜色样式转换位点。研究人员推断这种倒置是通过在基因渗入在谱系之间转移的，并且在同属的另一分支也发生类似的重排。这些多样性的从头基因组序列能够帮助人类理解在适应辐射过程中基因渗入和选择性过程的重要性。

附：英文原文

Title: Genomic architecture and introgression shape a butterfly radiation

Author: Nathaniel B. Edelman, Paul B. Frandsen, Michael Miyagi, Bernardo Clavijo, John Davey, Rebecca B. Dikow, Gonzalo García-Accinelli, Steven M. Van Belleghem, Nick Patterson, Daniel E. Neafsey, Richard Challis, Sujai Kumar, Gilson R. P. Moreira, Camilo Salazar, Mathieu Chouteau, Brian A. Counterman, Riccardo Papa, Mark Blaxter, Robert D. Reed, Kanchon K. Dasmahapatra, Marcus Kronforst, Mathieu Joron, Chris D. Jiggins, W. Owen McMillan, Federica Di Palma, Andrew J. Blumberg, John Wakeley, David Jaffe, James Mallet

Issue&Volume: 2019/11/01

Abstract: We used 20 de novo genome assemblies to probe the speciation history and architecture of gene flow in rapidly radiating Heliconius butterflies. Our tests to distinguish incomplete lineage sorting from introgression indicate that gene flow has obscured several ancient phylogenetic relationships in this group over large swathes of the genome. Introgressed loci are underrepresented in low-recombination and gene-rich regions, consistent with the purging of foreign alleles more tightly linked to incompatibility loci. Here, we identify a hitherto unknown inversion that traps a color pattern switch locus. We infer that this inversion was transferred between lineages by introgression and is convergent with a similar rearrangement in another part of the genus. These multiple de novo genome sequences enable improved understanding of the importance of introgression and selective processes in adaptive radiation.

DOI: 10.1126/science.aaw2090

Source:https://science.sciencemag.org/content/366/6465/594