Probing condensate microenvironments with a micropeptide killswitch

• 成果类型: Article
• 署名作者: Zhang, Yaotian; Stoeppelkamp, Ida; Fernandez-Pernas, Pablo; Allram, Melanie; Charman, Matthew; Magalhaes, Alexandre P.; Piedavent-Salomon, Melanie; Sommer, Gregor; Sung, Yu-Chieh; Meyer, Katrina; Grams, Nicholas; Halko, Edwin; Dongre, Shivali; Meierhofer, David; Malszycki, Michal; Ilik, Ibrahim A.; Aktas, Tugce; Kraushar, Matthew L.; Vastenhouw, Nadine; Weitzman, Matthew D.; Grebien, Florian; Niskanen, Henri; Hnisz, Denes
• 署名单位: Max Planck Society; Free University of Berlin; University of Veterinary Medicine Vienna; University of Pennsylvania; Pennsylvania Medicine; Childrens Hospital of Philadelphia; University of Pennsylvania; University of Pennsylvania; Pennsylvania Medicine; Childrens Hospital of Philadelphia; University of Lausanne; University of Pennsylvania; Saint Anna Children's Hospital; St. Anna Children's Cancer Research Institute (CCRI); Austrian Academy of Sciences; CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1331
• DOI: 10.1038/s41586-025-09141-5
• 发表日期: 2025-07-24
• 关键词: phase-separation; protein; transcription; ORGANIZATION; mechanism

摘要

Biomolecular condensates are thought to create subcellular microenvironments that have different physicochemical properties compared with their surrounding nucleoplasm or cytoplasm1, 2, 3, 4-5. 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 limited6, 7, 8-9. 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.