Kernel dehydration rate (KDR) is a crucial production trait that affects mechanized harvesting and kernel quality in maize; however, the underlying mechanisms remain unclear. Here, we identified a quantitative trait locus (QTL), qKDR1, as a non-coding sequence that regulates the expression of qKDR1 REGULATED PEPTIDE GENE (RPG). RPG encodes a 31 amino acid micropeptide, microRPG1, which controls KDR by precisely modulating the expression of two genes, ZmETHYLENE-INSENSITIVE3-like 1 and 3, in the ethylene signaling pathway in the kernels after filling. microRPG1 is a Zea genus-specific micropeptide and originated de novo from a non-coding sequence. Knockouts of microRPG1 result in faster KDR in maize. By contrast, overexpression or exogenous application of the micropeptide shows the opposite effect both in maize and Arabidopsis. Our findings reveal the molecular mechanism of microRPG1 in kernel dehydration and provide an important tool for future crop breeding.

中文翻译：

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玉米属特异性微肽控制玉米中的籽粒脱水


籽粒脱水率 （KDR） 是影响玉米机械化收获和籽粒质量的关键生产性状;然而，其潜在机制仍不清楚。在这里，我们确定了一个数量性状位点 （QTL） qKDR1 作为调节 qKDR1 调节肽基因 （RPG） 表达的非编码序列。RPG 编码一种 31 个氨基酸的微肽 microRPG1，它通过精确调节填充后籽粒中乙烯信号通路中两个基因（ZmETHYLENE-INSENSITIVE3 样 1 和 3）的表达来控制 KDR。microRPG1 是一种 Zea 属特异性微肽，起源于非编码序列。microRPG1 的敲除导致玉米中更快的 KDR。相比之下，微肽的过表达或外源应用在玉米和拟南芥中均显示出相反的效果。我们的研究结果揭示了 microRPG1 在籽粒脱水中的分子机制，为未来的作物育种提供了重要工具。