Exceptional subgenome stability and functional divergence in the allotetraploid Ethiopian cereal teff
Exceptional subgenome stability and functional divergence in the allotetraploid Ethiopian cereal teff
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DOI：
10.1038/s41467-020-14724-z
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发表时间：
2020-02-14
影响因子：
16.6
通讯作者：
Michael, Todd P.
中科院分区：
文献类型：
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作者：
VanBuren, Robert;Wai, Ching Man;Michael, Todd P.
苔麸（Eragrostis tef）是非洲之角粮食安全的基石，因其抗逆性、粮食营养和市场价值而受到重视。在这里，我们报道了异源四倍体teff （Dabbi品种）的染色体尺度组装和亚基因组动力学模式。画眉草基因组包含两套完整的同源染色体，大多数基因保持为同染色体对。TE分析使我们能够估计teff多倍体事件发生在110万年前（mya），两个亚基因组分化的时间类似于5万年前。尽管存在这种差异，但与许多其他异源多倍体相比，我们没有发现大规模的结构重排，同源交换或偏倚基因丢失。两个teff亚基因组基于不同表达图谱上的不同表达划分了它们的祖先功能。总之，这些基因组资源将有助于加速这种未充分利用的粮食作物的育种，并为多倍体基因组进化提供基础见解。
Teff (Eragrostis tef) is a cornerstone of food security in the Horn of Africa, where it is prized for stress resilience, grain nutrition, and market value. Here, we report a chromosome-scale assembly of allotetraploid teff (variety Dabbi) and patterns of subgenome dynamics. The teff genome contains two complete sets of homoeologous chromosomes, with most genes maintaining as syntenic gene pairs. TE analysis allows us to estimate that the teff polyploidy event occurred similar to 1.1 million years ago (mya) and that the two subgenomes diverged similar to 5.0 mya. Despite this divergence, we detect no large-scale structural rearrangements, homoeologous exchanges, or biased gene loss, in contrast to many other allopolyploids. The two teff sub-genomes have partitioned their ancestral functions based on divergent expression across a diverse expression atlas. Together, these genomic resources will be useful for accelerating breeding of this underutilized grain crop and for fundamental insights into polyploid genome evolution.