Single-parent expression drives dynamic gene expression complementation in maize hybrids
Single-parent expression drives dynamic gene expression complementation in maize hybrids
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单亲表达驱动玉米杂交种的动态基因表达互补
DOI：
10.1111/tpj.15042
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发表时间：
2020-11-29
期刊：
影响因子：
7.2
通讯作者：
Hirsch, Candice N.
中科院分区：
文献类型：
--
作者：
Li, Zhi;Zhou, Peng;Hirsch, Candice N.
单亲表达（Single-parent expression，SPE）是指基因只在双亲中的一方表达。SPE可以由亲本等位基因之间的差异表达引起，称为不存在/不存在（非PAV）SPE，或者由一个亲本中基因的物理缺失引起，称为PAV SPE。我们使用不同的玉米（玉米）自交系和杂交种，包括401个样品从五个不同的组织，转录组数据测试这些类型的SPE基因之间的差异。虽然经常观察到，SPE是高度基因型和组织特异性。两个自交系亲本间的遗传距离与所鉴定的SPE基因数呈正相关。调节分析表明，PAV SPE和非PAV SPE基因主要受顺式调节，有一小部分受反式调节。在启动子序列中插入多态性转座元件有助于高水平的顺式调节PAV SPE和非PAV SPE基因。PAV SPE基因在杂种中的表达频率高于非PAV SPE基因。亲本沉默等位基因在非PAV SPE基因的杂种中的表达相对较少，但在大多数杂种中发生。与不表达沉默等位基因的杂交体相比，在杂交体中表达沉默等位基因的非PAV SPE基因更可能表现出高于亲本的高表达水平，导致非加性表达。本研究为全面了解非PAV SPE和PAV SPE基因的性质及其在玉米杂交种基因表达互补中的作用提供了理论依据。
Single-parent expression (SPE) is defined as gene expression in only one of the two parents. SPE can arise from differential expression between parental alleles, termed non-presence/absence (non-PAV) SPE, or from the physical absence of a gene in one parent, termed PAV SPE. We used transcriptome data of diverse Zea mays (maize) inbreds and hybrids, including 401 samples from five different tissues, to test for differences between these types of SPE genes. Although commonly observed, SPE is highly genotype and tissue specific. A positive correlation was observed between the genetic distance of the two inbred parents and the number of SPE genes identified. Regulatory analysis showed that PAV SPE and non-PAV SPE genes are mainly regulated by cis effects, with a small fraction under trans regulation. Polymorphic transposable element insertions in promoter sequences contributed to the high level of cis regulation for PAV SPE and non-PAV SPE genes. PAV SPE genes were more frequently expressed in hybrids than non-PAV SPE genes. The expression of parentally silent alleles in hybrids of non-PAV SPE genes was relatively rare but occurred in most hybrids. Non-PAV SPE genes with expression of the silent allele in hybrids are more likely to exhibit above high parent expression level than hybrids that do not express the silent allele, leading to non-additive expression. This study provides a comprehensive understanding of the nature of non-PAV SPE and PAV SPE genes and their roles in gene expression complementation in maize hybrids.