Main conclusion

The post-transcriptional gene regulatory pathway and small RNA pathway play important roles in regulating the rapid and long-term response of Rhododendron moulmainense to high-temperature stress.

Abstract

The Rhododendron plays an important role in maintaining ecological balance. However, it is difficult to domesticate for use in urban ecosystems due to their strict optimum growth temperature condition, and its evolution and adaptation are little known. Here, we combined transcriptome and small RNAome to reveal the rapid response and long-term adaptability regulation strategies in Rhododendron moulmainense under high-temperature stress. The post-transcriptional gene regulatory pathway plays important roles in stress response, in which the protein folding pathway is rapidly induced at 4 h after heat stress, and alternative splicing plays an important role in regulating gene expression at 7 days after heat stress. The chloroplasts oxidative damage is the main factor inhibiting photosynthesis efficiency. Through WGCNA analysis, we identified gene association patterns and potential key regulatory genes responsible for maintaining the ROS steady-state under heat stress. Finally, we found that the sRNA synthesis pathway is induced under heat stress. Combined with small RNAome, we found that more miRNAs are significantly changed under long-term heat stress. Furthermore, MYBs might play a central role in target gene interaction network of differentially expressed miRNAs in R. moulmainense under heat stress. MYBs are closely related to ABA, consistently, ABA synthesis and signaling pathways are significantly inhibited, and the change in stomatal aperture is not obvious under heat stress. Taken together, we gained valuable insights into the transplantation and long-term conservation domestication of Rhododendron, and provide genetic resources for genetic modification and molecular breeding to improve heat resistance in Rhododendron.

中文翻译：

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转录组和小RNA组的综合分析揭示了毛迈杜鹃对热应激的快速和长期反应的调控网络

主要结论

转录后基因调控途径和小RNA途径在调节毛曼杜鹃对高温胁迫的快速、长期响应中发挥着重要作用。

抽象的

杜鹃花在维持生态平衡方面发挥着重要作用。然而，由于其最适生长温度条件严格，难以驯化用于城市生态系统，其进化和适应鲜为人知。在此，我们结合转录组和小RNA组揭示了毛迈杜鹃在高温胁迫下的快速响应和长期适应性调控策略。转录后基因调控途径在应激反应中发挥着重要作用，其中蛋白质折叠途径在热应激后4小时迅速诱导，而选择性剪接在热应激后7天起调节基因表达的重要作用。叶绿体氧化损伤是抑制光合作用效率的主要因素。通过 WGCNA 分析，我们确定了基因关联模式和负责在热应激下维持 ROS 稳态的潜在关键调控基因。最后，我们发现sRNA合成途径在热应激下被诱导。结合小RNAome，我们发现更多的miRNA在长期热应激下发生显着变化。此外，MYB 可能在热应激下毛曼红藻差异表达 miRNA 的靶基因相互作用网络中发挥核心作用。 MYBs与ABA密切相关，热胁迫下ABA合成和信号通路均受到显着抑制，气孔孔径变化不明显。综上所述，我们对杜鹃花的移植和长期保护驯化获得了宝贵的见解，为提高杜鹃花耐热性的遗传改造和分子育种提供了遗传资源。