biostudies-literature00450Banerjee PRNIGMS NIH HHS11354-11359https://www.ebi.ac.uk/biostudies/studies/S-EPMC5647147biostudies-literatureUnknown56(38)Intracellular ribonucleoprotein (RNP) granules are membrane-less droplet organelles that are thought to regulate posttranscriptional gene expression. While liquid-liquid phase separation may drive RNP granule assembly, the mechanisms underlying their supramolecular dynamics and internal organization remain poorly understood. Herein, we demonstrate that RNA, a primary component of RNP granules, can modulate the phase behavior of RNPs by controlling both droplet assembly and dissolution in?vitro. Monotonically increasing the RNA concentration initially leads to droplet assembly by complex coacervation and subsequently triggers an RNP charge inversion, which promotes disassembly. This RNA-mediated reentrant phase transition can drive the formation of dynamic droplet substructures (vacuoles) with tunable lifetimes. We propose that active cellular processes that can create an influx of RNA into RNP granules, such as transcription, can spatiotemporally control the organization and dynamics of such liquid-like organelles.Angewandte Chemie (International ed. in English)Reentrant Phase Transition Drives Dynamic Substructure Formation in Ribonucleoprotein Droplets.PMC5647147R01 GM115634R01 GM066833Milin ANOnuchic PLBanerjee PRDeniz AAMoosa MM45falseReentrant Phase Transition Drives Dynamic Substructure Formation in Ribonucleoprotein Droplets.Intracellular ribonucleoprotein (RNP) granules are membrane-less droplet organelles that are thought to regulate posttranscriptional gene expression. While liquid-liquid phase separation may drive RNP granule assembly, the mechanisms underlying their supramolecular dynamics and internal organization remain poorly understood. Herein, we demonstrate that RNA, a primary component of RNP granules, can modulate the phase behavior of RNPs by controlling both droplet assembly and dissolution in?vitro. Monotonically increasing the RNA concentration initially leads to droplet assembly by complex coacervation and subsequently triggers an RNP charge inversion, which promotes disassembly. This RNA-mediated reentrant phase transition can drive the formation of dynamic droplet substructures (vacuoles) with tunable lifetimes. We propose that active cellular processes that can create an influx of RNA into RNP granules, such as transcription, can spatiotemporally control the organization and dynamics of such liquid-like organelles.2017-01-01T00:00:00Z2017 Sep2020-11-01T08:43:30Z2019-03-26T23:55:04ZS-EPMC56471472855638210.1002/anie.201703191