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Title: RNA promotes phase separation of glycolysis enzymes into yeast G bodies in hypoxia
In hypoxic stress conditions, glycolysis enzymes assemble into singular cytoplasmic granules called glycolytic (G) bodies. G body formation in yeast correlates with increased glucose consumption and cell survival. However, the physical properties and organizing principles that define G body formation are unclear. We demonstrate that glycolysis enzymes are non-canonical RNA binding proteins, sharing many common mRNA substrates that are also integral constituents of G bodies. Targeting nonspecific endoribonucleases to G bodies reveals that RNA nucleates G body formation and maintains its structural integrity. Consistent with a phase separation mechanism of biogenesis, recruitment of glycolysis enzymes to G bodies relies on multivalent homotypic and heterotypic interactions. Furthermore, G bodies fuse in vivo and are largely insensitive to 1,6-hexanediol, consistent with a hydrogel-like composition. Taken together, our results elucidate the biophysical nature of G bodies and demonstrate that RNA nucleates phase separation of the glycolysis machinery in response to hypoxic stress.  more » « less
Award ID(s):
1430124
PAR ID:
10170287
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
eLife
Volume:
9
ISSN:
2050-084X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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