Stepwise selection on homeologous PRR genes controlling flowering and maturity during soybean domestication

First author: Sijia Lu; Affiliations: Guangzhou University (广州大学): Guangzhou, China

Corresponding author: Fanjiang Kong 

Adaptive changes in plant phenology are often considered to be a feature of the so-called ‘domestication syndrome’ that distinguishes modern crops from their wild progenitors, but little detailed evidence supports this idea. In soybean, a major legume crop, flowering time variation is well characterized within domesticated germplasm and is critical for modern production, but its importance during domestication is unclear. Here, we identify sequential contributions of two homeologous pseudo-response-regulator genes, Tof12 and Tof11, to ancient flowering time adaptation, and demonstrate that they act via LHY homologs to promote expression of the legume-specific E1 gene and delay flowering under long photoperiods. We show that Tof12-dependent acceleration of maturity accompanied a reduction in dormancy and seed dispersal during soybean domestication, possibly predisposing the incipient crop to latitudinal expansion. Better understanding of this early phase of crop evolution will help to identify functional variation lost during domestication and exploit its potential for future crop improvement.

植物物候的适应性变化通常被认为是驯化综合特征（domestication syndrome）的特性，从而将现代栽培种与其野生祖先种区别开来，但目前并没有多少实质性的证据来支持这一论点。在主要豆科植物大豆中，开花时间变异是一个熟知的的驯化种质，并且对于现代大豆的产量至关重要，但其在驯化过程中的重要性还不清楚。本文中，作者鉴定了大豆中两个伪应答调节（pseudo response regulator，PRR）同源基因Tof12和Tof11连续作用于古老的开花时间适应，并且揭示了这两个基因通过生物钟LHY同源基因促进豆科特异性的光周期开花调控网络中核心调控因子E1基因的表达，从而在长光周期的条件下延迟开花。作者的研究显示在大豆驯化过程中，Tof12依赖性的大豆成熟加速伴随着休眠和种子落粒的减少，这可能是初期大豆进行纬度扩张的一个诱因。对于作物演化早期阶段的深入了解将有助于我们鉴定驯化过程中这些作物丢失的功能变异，并探索其对于未来作物遗传改良的潜在影响。

通讯：孔凡江 (https://prl.natsci.msu.edu/people/faculty/sheng-yang-he/)

个人简介：1997年，东北农业大学，学士；2002年，东北农业大学，硕士；2006年，日本北海道大学，博士。

研究方向：主要从事控制大豆重要农艺性状的基因发掘和调控网络和大豆分子设计育种研究。

doi: https://doi.org/10.1038/s41588-020-0604-7

Journal: Nature Genetics

Published date: March 30, 2020

p.s. 大豆驯化相关研究链接：

Genome Biology：大豆野生种与驯化种之间基因滲入的演化模式

Nature Plants：大豆种油含量与种皮光滑性状驯化基因

Nature Communications：野生大豆基因组

Nature Genetics：多个作物驯化过程中种子休眠基因的平衡选择