RNA Dynamics Regulate Transcriptional Condensate Vivacity to Drive Gene Coordination

Transcriptional condensates (TCs), enriched with Mediator, orchestrate super-enhancer (SE)-driven gene expression critical for cell identity. However, how their dynamic physical properties shape transcriptional activities remains unclear. Here, we reveal a previously unknown regulatory axis wherein dynamic features of enhancer RNA (eRNA), transcribed but rapidly degraded by the RNA exosome, maintain optimal TC fluidity and stability. Depletion of RNA exosome disrupts TC integrity, altering Mediator and Pol II colocalization, in embryonic stem cells. This TC perturbation attenuates proper transcriptional regulator loading and pause-release regulation, enhances transcriptional noise, and diminishes coordinated eRNA-mRNA expression for SE-associated genes. Multi-omics analyses, live-cell imaging, and computational modeling collectively demonstrate that RNA turnover modulates TC vivacity, facilitating widespread chromatin contacts between SE-containing active A compartments and coordinated transcriptional bursts across SE-associated genes. Our findings establish RNA-dependent condensate dynamics as an essential quality-control mechanism that fine-tunes global transcriptional coordination, maintaining cellular homeostasis and cell identity.

RNA exosome is required for the homeostasis of transcriptional condensates (TCs)RNA synthesis and decay optimize the fluidity and dynamic properties of TCsTCs maintain the transcriptional consistency of super-enhancer (SE) genesTCs support contacts of SE-containing A compartments for coordinated transcription.