Probing condensate microenvironments with a micropeptide killswitch

Title (eng)
Probing condensate microenvironments with a micropeptide killswitch
Author
Yaotian Zhang
Author
Ida Stöppelkamp
Author
Pablo Fernandez-Pernas
Author
Melanie Allram
Author
Matthew Charman
Author
Alexandre P. Magalhaes
Author
Melanie Piedavent-Salomon
Author
Gregor Sommer
Author
Yu-Chieh Sung
Author
Katrina Meyer
Author
Nicholas Grams
Author
Edwin Halko
Author
Shivali Dongre
Author
David Meierhofer
Author
Michal Malszycki
Author
Ibrahim A. Ilik
Author
Tugce Aktas
Author
Matthew L. Kraushar
Author
Nadine Vastenhouw
Author
Matthew D. Weitzman
Author
Florian Grebien
Author
Henri Niskanen
Author
Denes Hnisz
Abstract (eng)
Biomolecular condensates are thought to create subcellular microenvironments that have different physicochemical properties compared with their surrounding nucleoplasm or cytoplasm. However, probing the microenvironments of condensates and their relationship to biological function is a major challenge because tools to selectively manipulate specific condensates in living cells are limited. Here, we develop a non-natural micropeptide (that is, the killswitch) and a nanobody-based recruitment system as a universal approach to probe endogenous condensates, and demonstrate direct links between condensate microenvironments and function in cells. The killswitch is a hydrophobic, aromatic-rich sequence with the ability to self-associate, and has no homology to human proteins. When recruited to endogenous and disease-specific condensates in human cells, the killswitch immobilized condensate-forming proteins, leading to both predicted and unexpected effects. Targeting the killswitch to the nucleolar protein NPM1 altered nucleolar composition and reduced the mobility of a ribosomal protein in nucleoli. Targeting the killswitch to fusion oncoprotein condensates altered condensate compositions and inhibited the proliferation of condensate-driven leukaemia cells. In adenoviral nuclear condensates, the killswitch inhibited partitioning of capsid proteins into condensates and suppressed viral particle assembly. The results suggest that the microenvironment within cellular condensates has an essential contribution to non-stoichiometric enrichment and mobility of effector proteins. The killswitch is a widely applicable tool to alter the material properties of endogenous condensates and, as a consequence, to probe functions of condensates linked to diverse physiological and pathological processes.
Keywords (eng)
Cell BiologyImagingMechanisms of DiseaseNuclear Organization
Type (eng)
journal article
Language
[eng]
Persistent identifier
https://phaidra.vetmeduni.ac.at/o:4943
DOI
10.1038/s41586-025-09141-5
Is in series
Title (eng)
Nature
Volume
643
Issue
8073
ISSN
0028-0836
Issued
2025
Number of pages
45
From page
1107
To page
1116
Publication
Springer
Version type (eng)
version of record (published version)
Date issued
2025
Access rights (eng)
open access
License
CC BY 4.0 International
Rights statement (eng)
© 2025, The Author(s)