Phase separation of YAP reorganizes genome topology for long-term, YAP target gene expression

作者：Danfeng Cai, Daniel Feliciano, Peng Dong, Eduardo Flores, Martin Gruebele, Natalie Porat‐Shliom, Shahar Sukenik, Zhe Liu, Jennifer Lippincott‐Schwartz · 发表于：bioRxiv (Cold Spring Harbor Laboratory) · 年份：2018 · DOI：10.1101/438416 · 被引用次数：39 · 研究领域：Hippo pathway signaling and YAP/TAZ、RNA Research and Splicing、Cancer-related gene regulation

Yes-associated Protein (YAP) is a transcriptional co-activator that regulates cell proliferation and survival by binding to a selective set of enhancers for potent target gene activation, but how YAP coordinates these transcriptional responses is unknown. Here, we demonstrate that YAP forms liquid-like condensates in the nucleus in response to macromolecular crowding. Formed within seconds of hyperosmotic stress, YAP condensates compartmentalized YAP’s DNA binding cofactor TEAD1 along with other YAP-related transcription co-activators, including TAZ, and subsequently induced transcription of YAP-specific proliferation genes. Super-resolution imaging using Assay for Transposase Accessible Chromatin with photoactivated localization microscopy (ATAC-PALM) revealed that YAP nuclear condensates were areas enriched in accessible chromatin domains organized as super-enhancers. Initially devoid of RNA Polymerase II (Pol II), the accessible chromatin domains later acquired Pol II, producing newly transcribed RNA. Removal of YAP’s intrinsically-disordered transcription activation domain (TAD) prevented YAP condensate formation and diminished downstream YAP signaling. Thus, dynamic changes in genome organization and gene activation during YAP reprogramming is mediated by liquid-liquid phase separation.