很少人知道,，百姓餐桌上經(jīng)常“露面”的白菜,、甘藍(lán),、芥菜和油菜等，在蔬菜專業(yè)研究領(lǐng)域都屬于蕓薹屬,。長(zhǎng)期以來,，這些蔬菜的“祖先”到底是誰？對(duì)于研究蕓薹屬植物起源與進(jìn)化的科學(xué)家來說一直是個(gè)難解之謎,。記者日前從中國(guó)農(nóng)業(yè)科學(xué)院獲悉,，該院蔬菜花卉研究所王曉武研究員帶領(lǐng)的科研團(tuán)隊(duì)對(duì)蕓薹屬物種基因組進(jìn)化的研究獲得了重要成果，相關(guān)研究論文近日在國(guó)際學(xué)術(shù)期刊《植物細(xì)胞》上在線發(fā)表,，同時(shí)發(fā)表的還有《植物細(xì)胞》主編對(duì)該論文的推薦文章《重建白菜祖先基因組》,。
該研究在完成白菜基因組測(cè)序的基礎(chǔ)上，首次明確了蕓薹屬及其近緣物種具有七條染色體的共同祖先基因組,，闡明了蕓薹屬基因組進(jìn)化的關(guān)鍵環(huán)節(jié),。在此基礎(chǔ)上，重新構(gòu)建了白菜的三個(gè)亞基因組,，并精確定義了十字花科模式基因組的7個(gè)重組區(qū)塊,，解決了白菜、甘藍(lán),、油菜,、蘿卜等重要作物多年未解的染色體進(jìn)化難題。
業(yè)內(nèi)專家表示,，明確蕓薹屬及其近緣物種共同祖先的基因組,，不僅對(duì)闡明蕓薹屬作物的進(jìn)化過程具有重要意義，而且對(duì)蕓薹屬基因功能研究將產(chǎn)生重大影響,。王曉武研究員帶領(lǐng)的科研團(tuán)隊(duì)多年從事蕓薹屬物種的研究,，主導(dǎo)了白菜基因組的測(cè)序工作。（生物谷Bioon.com）
生物谷推薦英文摘要：
The plant cell doi:10.1105/tpc.113.110486
Deciphering the Diploid Ancestral Genome of the Mesohexaploid Brassica rapa
Feng Cheng, Terezie Mandáková, Jian Wua, Qi Xie, Martin A. Lysak, and Xiaowu Wang
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.
