Department of Plant Pathology, Kansas State University, Manhattan, KS, USA.
State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2022 Feb 11;13(1):826. doi: 10.1038/s41467-022-28453-y.
Allopolyploidy greatly expands the range of possible regulatory interactions among functionally redundant homoeologous genes. However, connection between the emerging regulatory complexity and expression and phenotypic diversity in polyploid crops remains elusive. Here, we use diverse wheat accessions to map expression quantitative trait loci (eQTL) and evaluate their effects on the population-scale variation in homoeolog expression dosage. The relative contribution of cis- and trans-eQTL to homoeolog expression variation is strongly affected by both selection and demographic events. Though trans-acting effects play major role in expression regulation, the expression dosage of homoeologs is largely influenced by cis-acting variants, which appear to be subjected to selection. The frequency and expression of homoeologous gene alleles showing strong expression dosage bias are predictive of variation in yield-related traits, and have likely been impacted by breeding for increased productivity. Our study highlights the importance of genomic variants affecting homoeolog expression dosage in shaping agronomic phenotypes and points at their potential utility for improving yield in polyploid crops.
异源多倍化极大地扩展了功能冗余的同源基因之间可能的调控相互作用的范围。然而，新兴的调控复杂性与多倍体作物的表达和表型多样性之间的联系仍然难以捉摸。在这里，我们使用不同的小麦品系来映射表达数量性状基因座 (eQTL)，并评估它们对同源基因表达剂量在群体水平上的变化的影响。顺式和反式 eQTL 对同源基因表达变化的相对贡献强烈受到选择和人口事件的影响。尽管反式作用在表达调控中起着主要作用，但同源基因的表达剂量在很大程度上受到顺式作用变体的影响，这些变体似乎受到了选择的影响。表现出强烈表达剂量偏倚的同源基因等位基因的频率和表达可预测与产量相关性状的变异，并且可能受到提高生产力的选育的影响。我们的研究强调了影响同源基因表达剂量的基因组变异在塑造农艺表型方面的重要性，并指出它们在提高多倍体作物产量方面具有潜在的应用价值。
