Single-parent expression complementation contributes to phenotypic heterosis in maize hybrids

第一作者：Jutta A Baldauf

第一单位：德国波恩大学

通讯作者：Frank Hochholdinger

 Abstarct 

背景回顾：The dominance model of heterosis explains the superior performance of F1 hybrids via the complementation of deleterious alleles by beneficial alleles in many genes. Genes active in one parent but inactive in the second lead to single-parent expression (SPE) complementation in maize (Zea mays L.) hybrids. 

杂种优势的显性模型通过许多基因中有害等位基因被有益等位基因互补来解释F1杂种的优越表现。在玉米杂种中，来自亲本一方的等位基因被激活，而对应的来自另一亲本的等位基因失活，导致了单亲本表达（SPE）互补。

主要研究：In this study, SPE complementation resulted in ∼700 additionally active genes in different tissues of genetically diverse maize hybrids on average. 

本文中，作者发现在不同的玉米种质材料的不同组织中，SPE互补平均导致了约700多个额外的激活基因。

结果1-SPE基因与杂种优势：We established that the number of SPE genes is significantly associated with mid-parent heterosis for all surveyed phenotypic traits. 

作者发现，SPE基因的数目与所有调查性状的中亲杂种优势显著相关。

结果2-单亲SPE互补与杂种优势：In addition, we highlighted that maternally (SPE_B) and paternally (SPE_X) active SPE genes enriched in gene co-expression modules are highly correlated within each SPE type but separated between these two SPE types. While SPE_B-enriched co-expression modules are positively correlated with phenotypic traits, SPE_X-enriched modules displayed a negative correlation. Gene Ontology (GO) term enrichment analyses indicated that SPE_B patterns are associated with growth and development, whereas SPE_X patterns are enriched in defense and stress response. 

另外，作者还发现在基因共表达模块中富集的母系和父系激活SPE基因与各自的SPE类型高度相关，但是在不同的SPE类型之间分得很开。当富集母系激活SPE基因的共表达模块与表型性状呈正相关关系，而富集父系激活SPE基因的模块则表现出负相关关系。GO富集分析显示，母系激活SPE基因主要与生长和发育相关，而父系激活SPE基因则富集于防御和胁迫响应。

结论：In summary, these results link the degree of phenotypic mid-parent heterosis to the prevalence of gene expression complementation observed by SPE, supporting the notion that hybrids benefit from SPE complementation via its role in coordinating maize development in fluctuating environments.

综上，本文的研究结果关联了表型中亲杂种优势程度与通过SPE所观察到的基因表达互补程度，表明SPE互补通过其在波动环境中协调玉米发育，从而促进杂种优势。

 Frank Hochholdinger 

doi: https://doi.org/10.1093/plphys/kiac180

Journal: Plant Physiology

Published date: April 21, 2022