The abundance of homoeologue transcripts is disrupted by hybridization and is partially restored by genome doubling in synthetic hexaploid wheat.
The abundance of homoeologue transcripts is disrupted by hybridization and is partially restored by genome doubling in synthetic hexaploid wheat.
复制标题
在合成六倍体小麦中，同源转录物的丰度因杂交而被破坏，并通过基因组加倍而部分恢复。
DOI：
10.1186/s12864-017-3558-0
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发表时间：
2017-02-10
期刊：
影响因子：
4.4
通讯作者：
Liu D
中科院分区：
文献类型：
--
作者：
Hao M;Li A;Shi T;Luo J;Zhang L;Zhang X;Ning S;Yuan Z;Zeng D;Kong X;Li X;Zheng H;Lan X;Zhang H;Zheng Y;Mao L;Liu D
异源多倍体的形成是一个两步过程，包括最初的广泛杂交事件，随后是全基因组加倍。这两个过程都可以影响同源物的转录。本研究利用RNA-Seq技术获得了两个独立的小麦×节节麦异源三倍体（F1）沿着自发异源六倍体（S1）及其亲本的全基因组叶片转录组。然后将所得序列数据用于表征同源物转录物丰度的变化。杂交事件强烈下调D-亚基因组同源物，但这种影响在许多情况下被逆转的全基因组加倍。D-亚基因组同源物转录的抑制导致亲本转录水平显性的显著频率，特别是相对于编码参与光合作用的蛋白质的基因。在异源三倍体和异源六倍体植物中，单基因（不存在同源物的基因）经常被转录。这意味着全基因组加倍有助于克服异源三倍体的表型弱点，在六倍体小麦中经历转录水平显性的基因中恢复更有利的基因剂量。本文的在线版本（doi：10.1186/s12864-017-3558-0）包含补充材料，可供授权用户使用。
The formation of an allopolyploid is a two step process, comprising an initial wide hybridization event, which is later followed by a whole genome doubling. Both processes can affect the transcription of homoeologues. Here, RNA-Seq was used to obtain the genome-wide leaf transcriptome of two independent Triticum turgidum × Aegilops tauschii allotriploids (F1), along with their spontaneous allohexaploids (S1) and their parental lines. The resulting sequence data were then used to characterize variation in homoeologue transcript abundance. The hybridization event strongly down-regulated D-subgenome homoeologues, but this effect was in many cases reversed by whole genome doubling. The suppression of D-subgenome homoeologue transcription resulted in a marked frequency of parental transcription level dominance, especially with respect to genes encoding proteins involved in photosynthesis. Singletons (genes where no homoeologues were present) were frequently transcribed at both the allotriploid and allohexaploid plants. The implication is that whole genome doubling helps to overcome the phenotypic weakness of the allotriploid, restoring a more favourable gene dosage in genes experiencing transcription level dominance in hexaploid wheat. The online version of this article (doi:10.1186/s12864-017-3558-0) contains supplementary material, which is available to authorized users.