Liquid demixing of intrinsically disordered proteins is seeded by poly(ADP-ribose).
Intrinsically disordered proteins can phase separate from the soluble intracellular space, and tend to aggregate under pathological conditions. The physiological functions and molecular triggers of liquid demixing by phase separation are not well understood. Here we show in vitro and in vivo that the nucleic acid-mimicking biopolymer poly(ADP-ribose) (PAR) nucleates intracellular liquid demixing. PAR levels are markedly induced at sites of DNA damage, and we provide evidence that PAR-seeded liquid demixing results in rapid, yet transient and fully reversible assembly of various intrinsically disordered proteins at DNA break sites. Demixing, which relies on electrostatic interactions between positively charged RGG repeats and negatively charged PAR, is amplified by aggregation-prone prion-like domains, and orchestrates the earliest cellular responses to DNA breakage. We propose that PAR-seeded liquid demixing is a general mechanism to dynamically reorganize the soluble nuclear space with implications for pathological protein aggregation caused by derailed phase separation.
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.|Institute of Veterinary Biochemistry and Molecular Biology, University of Zurich, Winterthurerstrasse 190, Zurich CH-8057, Switzerland.
Matthias
M
Altmeyer
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Kai J
KJ
Neelsen
Institute of Veterinary Biochemistry and Molecular Biology, University of Zurich, Winterthurerstrasse 190, Zurich CH-8057, Switzerland.
Federico
http://orcid.org/0000-0003-0953-8010
F
Teloni
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Irina
I
Pozdnyakova
Institute of Veterinary Biochemistry and Molecular Biology, University of Zurich, Winterthurerstrasse 190, Zurich CH-8057, Switzerland.
Stefania
S
Pellegrino
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Merete
M
Grøfte
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Maj-Britt Druedahl
MD
Rask
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Werner
W
Streicher
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Stephanie
S
Jungmichel
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Michael Lund
ML
Nielsen
Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3b, Copenhagen DK-2200, Denmark.
Jiri
J
Lukas
D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D004249:DNA Damage; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D011064:Poly Adenosine Diphosphate Ribose / Q000737:chemistry*; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D011506:Proteins; D011064:Poly Adenosine Diphosphate Ribose