Coexisting Liquid Phases Underlie Nucleolar Subcompartments.

TitleCoexisting Liquid Phases Underlie Nucleolar Subcompartments.
Publication TypeJournal Article
Year of Publication2016
AuthorsFeric, M, Vaidya, N, Harmon, TS, Mitrea, DM, Zhu, L, Richardson, TM, Kriwacki, RW, Pappu, RV, Brangwynne, CP
Date Published2016 Jun 16
KeywordsAnimals, Caenorhabditis elegans, Cell Nucleolus, Cells, Cultured, Chromosomal Proteins, Non-Histone, Intestines, Mammals, Nuclear Proteins, Nucleophosmin, Oocytes, Ribonucleoproteins, RNA Processing, Post-Transcriptional, Xenopus laevis

<p>The nucleolus and other ribonucleoprotein (RNP) bodies are membrane-less organelles that appear to assemble through phase separation of their molecular components. However, many such RNP bodies contain internal subcompartments, and the mechanism of their formation remains unclear. Here, we combine in vivo and in vitro studies, together with computational modeling, to show that subcompartments within the nucleolus represent distinct, coexisting liquid phases. Consistent with their in vivo immiscibility, purified nucleolar proteins phase separate into droplets containing distinct non-coalescing phases that are remarkably similar to nucleoli in vivo. This layered droplet organization is caused by differences in the biophysical properties of the phases-particularly droplet surface tension-which arises from sequence-encoded features of their macromolecular components. These results suggest that phase separation can give rise to multilayered liquids that may facilitate sequential RNA processing reactions in a variety of RNP bodies. PAPERCLIP.</p>

Alternate JournalCell
PubMed ID27212236
PubMed Central IDPMC5127388
Grant ListDP2 GM105437 / GM / NIGMS NIH HHS / United States
P30 CA021765 / CA / NCI NIH HHS / United States
R01 GM115634 / GM / NIGMS NIH HHS / United States
R01 NS056114 / NS / NINDS NIH HHS / United States