Cytonuclear coevolution following homoploid hybrid speciation in Aegilops tauschii

First author: Changping Li; Affiliations: Northeast Normal University (东北师范大学): Changchun, China

Corresponding author: Lei Gong

The diploid D-genome lineage of the Triticum/Aegilops complex has an evolutionary history involving genomic contributions from ancient A- and B/S-genome species. We explored here the possible cytonuclear (核质) evolutionary responses to this history of hybridization. Phylogenetic analysis of chloroplast DNAs indicate that the D-genome lineage has a maternal origin of the A-genome or some other closely allied (同源的) lineage. Analyses of the nuclear genome in the D-genome species Aegilops tauschii indicate that accompanying and/or following this ancient hybridization, there has been biased maintenance of maternal A-genome ancestry in nuclear genes encoding cytonuclear enzyme complexes (CECs). Our study provides insights into mechanisms of cytonuclear coevolution accompanying the evolution and eventual stabilization of homoploid hybrid species. We suggest that this coevolutionary process includes likely rapid fixation of A-genome CEC orthologs as well as biased retention of A-genome nucleotides in CEC homologs following population level recombination during the initial generations.

小麦/山羊草复合体的二倍体D套基因组涉及到了古老的A-和B/S套基因组的演化历史。本文中，作者研究了响应于杂交历史的核质演化。对于叶绿体DNA的进化分析显示D套基因组可能起源于母本的A套基因组或者其它的近缘谱系。对于含有D套基因组的山羊草的核基因组分析显示伴随着或跟着这次古老的杂交事件，编码核质酶复合物CEC的核基因中保留了更多的母本A套基因组。作者的研究揭示了伴随着同倍体杂交物种的演化和最终稳定过程中的核质协同演化。本文的研究显示该协同演化过程包括了在最初形成的杂种中伴随着群体级别的重组，A套基因组的CEC同源基因得到了快速固定，同时CEC同源基因中A套基因组核苷酸得到了偏性保留。

通讯：宫磊  (http://js.nenu.edu.cn/teacher/index.php?zgh=2015900003)

个人简介：2001-2005年，东北师范大学，学士；2005-2008年，遗传与细胞研究所，遗传学硕士；2008-2014年，美国爱荷华州州立大学，遗传学／生物信息及计算生物学博士。

研究方向：从核质协同进化、miRNA和siRNA的遗传改变等角度，深入系统的研究了棉属、拟南芥、花生、芸苔以及烟草等模式多倍体植物和作物的分子进化模式和遗传驱动机制。

doi: https://doi.org/10.1093/molbev/msy215

Journal: Molecular Biology and Evolution

Published date: 16 November, 2018