Tuber dormancy and sprouting are significant for potato cultivation, storage, and processing. Although the substantial role of miRNAs in some biological processes has been recognized, the critical role of miRNA in breaking potato tuber dormancy is not well understood to date. In this investigation, we expand research on miRNA-mediated gene regulation in tuber dormancy release. In this work, 204 known and 192 novel miRNAs were identified. 136 differentially expressed miRNAs (DE-miRNAs) were also screened out, of which 56 DE-miRNAs were regulated by temperature during tuber dormancy release. Additionally, degradome sequencing revealed that 821 target genes for 202 miRNAs were discovered. Among them, 63 target genes and 48 miRNAs were predicted to be involved in plant hormone signaling pathways. This study used degradome sequencing, tobacco co-transformation system, and GUS staining technology to confirm that stu-miR319c can target StTCP26 and StTCP27 and effectively suppress their expression. The transgenic approach exhibited that stu-miR319c overexpressed tubers sprouted in advance, while silent expression of stu-miR319c showed delayed sprouting. Treatment of wild-type tubers with exogenous MeJA revealed that 1 mg/L MeJA significantly broke dormancy and enhanced potato sprouting ability. Furthermore, transgenic tubers revealed variance in JA content and relative expression of genes associated with JA synthesis pathway, including StAOC, StLOX2, and StLOX4, suggesting that the miR319c may participate in the JA pathway to regulate tuber dormancy release. In summary, our research offers evidence that miRNA regulates potato dormancy release and supports the idea that stu-miR319c is a unique epigenetic regulator for dormancy-sprouting transition in potatoes.

中文翻译：

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非编码 RNA 的全基因组分析揭示了新型 miR319c 在马铃薯块茎休眠释放过程中的作用


块茎休眠和发芽对马铃薯的种植、储存和加工具有重要意义。尽管 miRNA 在某些生物过程中的重要作用已被认识到，但迄今为止，miRNA 在打破马铃薯块茎休眠中的关键作用尚不清楚。在这项研究中，我们扩展了对块茎休眠释放中 miRNA 介导的基因调控的研究。在这项工作中，鉴定了 204 个已知 miRNA 和 192 个新型 miRNA。筛选出 136 个差异表达 miRNAs （DE-miRNA），其中 56 个 DE-miRNAs 受块茎休眠释放过程中温度的调控。此外，降解组测序显示发现了 202 个 miRNAs 的 821 个靶基因。其中，预测 63 个靶基因和 48 个 miRNAs 参与植物激素信号通路。本研究采用降解组测序、烟草共转化系统和 GUS 染色技术证实 stu-miR319c 可以靶向 StTCP26 和 StTCP27 并有效抑制它们的表达。转基因方法显示 stu-miR319c 过表达块茎提前发芽，而 stu-miR319c 的默默表达表现为延迟发芽。外源 MeJA 处理野生型块茎后发现，1 mg/L MeJA 显著打破休眠，增强马铃薯发芽能力。此外，转基因块茎揭示了 JA 含量的变异以及与 JA 合成途径相关的基因（包括 StAOC 、 StLOX2 和 StLOX4）的相对表达，表明 miR319c 可能参与 JA 途径以调节块茎休眠释放。总之，我们的研究提供了 miRNA 调节马铃薯休眠释放的证据，并支持 stu-miR319c 是马铃薯休眠-发芽过渡的独特表观遗传调节因子的观点。