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：

---

SIZ1 介导的 CPSF100 SUMO 化通过控制选择性多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节来调整其形态以适应环境。然而，替代多腺苷酸化（APA）是基因表达的重要微调，其功能和调节在植物热形态发生中仍然未知。在这项研究中，我们发现 SUMO 化（一种关键的翻译后修饰）是通过在高温下通过 SUMO 连接酶 SIZ1 进行长期处理而诱导的。破坏改变了聚腺苷酸化信号的整体使用并影响了热形态发生相关基因的 APA 动态。 CPSF100 是 CPSF 复合物中用于多腺苷酸化调节的关键亚基，由 SIZ1 进行 SUMO 化。重要的是，我们证明 SUMO 化对于 CPSF100 在热形态发生过程中全基因组多腺苷酸化位点选择中的功能至关重要。进一步的分析表明，CPSF100 上的 SUMO 缀合减弱了其与其伙伴 CPSF30 的两种亚型的相互作用，增加了 CPSF100 用于多腺苷酸化调节的核积累。总之，我们的研究揭示了 APA 通过 SIZ1 介导的 SUMOylation 在植物热形态发生中的调节机制。