Under warm temperatures, plants adjust their morphologies for environmental adaption via precise gene expression regulation. However, the function and regulation of alternative polyadenylation (APA), an important fine-tuning of gene expression, remains unknown in plant thermomorphogenesis. In this study, we found that SUMOylation, a critical post-translational modification, is induced by a long-term treatment at warm temperatures via a SUMO ligase SIZ1 in . Disruption of altered the global usage of polyadenylation signals and affected the APA dynamic of thermomorphogenesis-related genes. CPSF100, a key subunit of the CPSF complex for polyadenylation regulation, is SUMOylated by SIZ1. Importantly, we demonstrated that SUMOylation is essential for the function of CPSF100 in genome-wide polyadenylation site choice during thermomorphogenesis. Further analyses revealed that the SUMO conjugation on CPSF100 attenuates its interaction with two isoforms of its partner CPSF30, increasing the nuclear accumulation of CPSF100 for polyadenylation regulation. In summary, our study uncovers a regulatory mechanism of APA via SIZ1-mediated SUMOylation in plant thermomorphogenesis.

中文翻译：

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SIZ1 介导的 CPSF100 的 SUMOylation 通过控制选择性多聚腺苷酸化促进植物热形态发生


在温暖的温度下，植物通过精确的基因表达调控来调整其形态以适应环境。然而，选择性多聚腺苷酸化 （APA） 的功能和调节是基因表达的重要微调，在植物热形态发生中仍然未知。在这项研究中，我们发现 SUMOylation 是一种关键的翻译后修饰，是通过在温暖温度下通过 SUMO 连接酶 SIZ1 在 .破坏改变了多聚腺苷酸化信号的全局使用，并影响了热形态发生相关基因的 APA 动力学。CPSF100 是 CPSF 复合体中用于多聚腺苷酸化调节的关键亚基，被 SIZ1 SUMO化。重要的是，我们证明了 SUMOylation 对于热形态发生过程中全基因组多聚腺苷酸化位点选择中 CPSF100 的功能至关重要。进一步分析表明，CPSF100 上的 SUMO 偶联减弱了其与其伴侣 CPSF30 的两种亚型的相互作用，增加了CPSF100的核积累以调节聚腺苷酸化。总之，我们的研究揭示了 APA 在 SIZ1 介导的植物热形态发生中通过 SUMOylation 的调节机制。