EAGER: Allopolyploidy and photosynthesis: a whole-transcriptome approach

异源多倍体（杂交后的全基因组重复）是开花植物物种形成的重要机制；许多作物，包括大豆（Glycine max），都是多倍体。同种异体多倍体是已知的导致结构和调控的变化，可以导致形态，生理和生态的新奇。人们对确定是否存在突现特性（“规则”）可能导致如此多的异源多倍体的明显成功非常感兴趣。甘氨酸是解决这个问题的一个很好的模型；在其大约30个物种中，有8个最近形成的异源四倍体物种，它们将8个二倍体祖先的基因组以不同的组合组合在一起。与所有局限于澳大利亚的二倍体不同，8种异源多倍体中有5种已经在太平洋的岛屿上定居，这表明它们比它们的祖先有更大的生态广度。光保护（Photoprotection）是一套消除潜在有害的多余光能的机制，是一个重要的适应性生理过程，可能有助于甘氨酸异源多倍体的成功。我们正在使用“下一代”，高通量测序方法（Illumina）获得三种甘氨酸异源多倍体物种及其二倍体祖细胞在正常光照和强光胁迫条件下基因表达的深入和详细信息，以评估哪些基因参与光保护，它们如何在二倍体和多倍体中受到调节，两个二倍体祖细胞基因组在每个多倍体中数千个表达基因中的贡献是什么。以及在独立形成的异源多倍体中是否存在共同的基因表达模式，这可能构成控制甘氨酸和其他开花植物多倍体物种光保护的可预测“规则”。更广泛的影响包括加深我们对多倍体的理解，这一过程塑造了许多农业上重要的植物物种的基因组；该项目还将支持一名研究生的培训。

Allopolyploidy (whole genome duplication following hybridization) is an important speciation mechanism in flowering plants; many crop species, including soybean (Glycine max), are polyploids. Allopolyploidy is known to lead to structural and regulatory changes that can result in morphological, physiological, and ecological novelty. There is considerable interest in ascertaining whether there are emergent properties ('rules') that could be responsible for the apparent success of so many allopolyploids. Glycine is an excellent model for addressing this question; among its approximately 30 species is a group of eight recently formed allotetraploid species uniting genomes from eight diploid progenitors in various combinations. Unlike any of the diploids, which are all confined to Australia, five of the eight allopolyploids have colonized islands of the Pacific Ocean, suggesting that they have a greater ecological breadth than their progenitors. Photoprotection - a set of mechanisms for dissipating potentially damaging excess light energy - is an adaptively important physiological process that could contribute to the success of Glycine allopolyploids. We are using a "next generation," high-throughput sequencing method (Illumina) to obtain a deep and detailed profile of gene expression in three Glycine allopolyploid species and their diploid progenitors under normal light and high light stress conditions to assess which genes are involved in photoprotection, how they are regulated in diploids and polyploids, what the contribution of the two diploid progenitor genomes is at each of thousands of expressed genes in each polyploid, and whether there are shared patterns of gene expression in independently formed allopolyploids that could constitute predictable 'rules' governing photoprotection in polyploid species of Glycine and other flowering plants. Broader impacts include deepening our understanding of polyploidy, a process that has shaped the genomes of many agriculturally important plant species; the project will also support training of a graduate student.