Deciphering the Diploid Ancestral Genome of the Mesohexaploid Brassica rapa

文献类型： 外文期刊

第一作者： Cheng, Feng

作者： Cheng, Feng;Wu, Jian;Wang, Xiaowu;Mandakova, Terezie;Lysak, Martin A.;Mandakova, Terezie;Lysak, Martin A.;Xie, Qi

作者机构：

期刊名称：PLANT CELL （ 影响因子：11.277； 五年影响因子：12.061 ）

ISSN： 1040-4651

年卷期： 2013 年 25 卷 5 期

页码：

收录情况： SCI

摘要： The genus Brassica includes several important agricultural and horticultural crops. Their current genome structures were shaped by whole-genome triplication followed by extensive diploidization. The availability of several crucifer genome sequences, especially that of Chinese cabbage (Brassica rapa), enables study of the evolution of the mesohexaploid Brassica genomes from their diploid progenitors. We reconstructed three ancestral subgenomes of B. rapa (n = 10) by comparing its whole-genome sequence to ancestral and extant Brassicaceae genomes. All three B. rapa paleogenomes apparently consisted of seven chromosomes, similar to the ancestral translocation Proto-Calepineae Karyotype (tPCK; n = 7), which is the evolutionarily younger variant of the Proto-Calepineae Karyotype (n = 7). Based on comparative analysis of genome sequences or linkage maps of Brassica oleracea, Brassica nigra, radish (Raphanus sativus), and other closely related species, we propose a two-step merging of three tPCK-like genomes to form the hexaploid ancestor of the tribe Brassiceae with 42 chromosomes. Subsequent diversification of the Brassiceae was marked by extensive genome reshuffling and chromosome number reduction mediated by translocation events and followed by loss and/or inactivation of centromeres. Furthermore, via interspecies genome comparison, we refined intervals for seven of the genomic blocks of the Ancestral Crucifer Karyotype (n = 8), thus revising the key reference genome for evolutionary genomics of crucifers.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序