The post-translational protein modification known as SUMOylation has conserved roles in the heat stress responses of various species. The functional connection between the global regulation of gene expression and chromatin-associated SUMOylation in plant cells is unknown. Here, we uncovered a genome-wide relationship between chromatin-associated SUMOylation and transcriptional switches in Arabidopsis thaliana grown at room temperature, exposed to heat stress, and exposed to heat stress followed by recovery. The small ubiquitin-like modifier (SUMO)-associated chromatin sites, characterized by whole-genome ChIP-seq, were generally associated with active chromatin markers. In response to heat stress, chromatin-associated SUMO signals increased at promoter-transcriptional start site regions and decreased in gene bodies. RNA-seq analysis supported the role of chromatin-associated SUMOylation in transcriptional activation during rapid responses to high temperature. Changes in SUMO signals on chromatin were associated with the upregulation of heat-responsive genes and the downregulation of growth-related genes. Disruption of the SUMO ligase gene SIZ1 abolished SUMO signals on chromatin and attenuated rapid transcriptional responses to heat stress. The SUMO signal peaks were enriched in DNA elements recognized by distinct groups of transcription factors under different temperature conditions. These observations provide evidence that chromatin-associated SUMOylation regulates the transcriptional switch between development and heat stress response in plant cells.

被称为 SUMOylation 的翻译后蛋白质修饰在各种物种的热应激反应中具有保守的作用。基因表达的全局调控与植物细胞中染色质相关的 SUMOylation 之间的功能联系尚不清楚。在这里，我们发现了拟南芥中染色质相关的 SUMOylation 和转录开关之间的全基因组关系在室温下生长，暴露于热应力，并暴露于热应力然后恢复。以全基因组 ChIP-seq 为特征的小泛素样修饰符 (SUMO) 相关染色质位点通常与活性染色质标记相关。响应热应激，染色质相关的相扑信号在启动子转录起始位点区域增加，在基因体中减少。RNA-seq 分析支持染色质相关的 SUMOylation 在对高温快速反应期间转录激活中的作用。染色质上SUMO信号的变化与热响应基因的上调和生长相关基因的下调有关。SUMO 连接酶基因SIZ1 的破坏消除染色质上的相扑信号并减弱对热应激的快速转录反应。SUMO 信号峰富含在不同温度条件下被不同转录因子组识别的 DNA 元件。这些观察结果证明染色质相关的 SUMOylation 调节植物细胞中发育和热应激反应之间的转录转换。