title: RNA Controls PolyQ Protein Phase Transitions.
abstract: Compartmentalization in cells is central to the spatial and temporal control of biochemistry. In addition to membrane-bound organelles, membrane-less compartments form partitions in cells. Increasing evidence suggests that these compartments assemble through liquid-liquid phase separation. However, the spatiotemporal control of their assembly, and how they maintain distinct functional and physical identities, is poorly understood. We have previously shown an RNA-binding protein with a polyQ-expansion called Whi3 is essential for the spatial patterning of cyclin and formin transcripts in cytosol. Here, we show that specific mRNAs that are known physiological targets of Whi3 drive phase separation. mRNA can alter the viscosity of droplets, their propensity to fuse, and the exchange rates of components with bulk solution. Different mRNAs impart distinct biophysical properties of droplets, indicating mRNA can bring individuality to assemblies. Our findings suggest that mRNAs can encode not only genetic information but also the biophysical properties of phase-separated compartments.
authors.affiliation: Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA; Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Huaiying
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Shana
authors.initials: S
authors.lastname: Elbaum-Garfinkle
authors.affiliation: Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA.
authors.forename: Erin M
authors.initials: EM
authors.lastname: Langdon
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Taylor
authors.affiliation: Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Occhipinti
authors.affiliation: Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA.
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Bridges
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA. Electronic address: cbrangwy@princeton.edu.
authors.forename: Clifford P
authors.initials: CP
authors.lastname: Brangwynne
authors.affiliation: Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA. Electronic address: amy.gladfelter@dartmouth.edu.
authors.forename: Amy S
authors.initials: AS
authors.lastname: Gladfelter
mesh_terms: D002451:Cell Compartmentation; D016213:Cyclins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D015966:Gene Expression Regulation, Fungal; D008840:Microfilament Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015388:Organelles / Q000737:chemistry / Q000378:metabolism; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D044367:Phase Transition; D012331:RNA, Fungal / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012212:Rheology; D004718:Saccharomycetales / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D016213:Cyclins; D005656:Fungal Proteins; D008840:Microfilament Proteins; D010455:Peptides; D012331:RNA, Fungal; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; C097188:polyglutamine