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  • Perspective
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Advances in mass spectrometry to unravel the structure and function of protein condensates

Nature Protocols volume 18, pages 3653–3661 (2023)Cite this article

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Abstract

Membrane-less organelles assemble through liquid–liquid phase separation (LLPS) of partially disordered proteins into highly specialized microenvironments. Currently, it is challenging to obtain a clear understanding of the relationship between the structure and function of phase-separated protein assemblies, owing to their size, dynamics and heterogeneity. In this Perspective, we discuss recent advances in mass spectrometry (MS) that offer several promising approaches for the study of protein LLPS. We survey MS tools that have provided valuable insights into other insoluble protein systems, such as amyloids, and describe how they can also be applied to study proteins that undergo LLPS. On the basis of these recent advances, we propose to integrate MS into the experimental workflow for LLPS studies. We identify specific challenges and future opportunities for the analysis of protein condensate structure and function by MS.

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Fig. 1: Possible strategies for investigating amyloid formation and LLPS with MS.
Fig. 2: Insights into the TDP-43 assembly process from MS.
Fig. 3: MS in the experimental LLPS workflow, and some current challenges.

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All data are available from the corresponding authors upon reasonable request.

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Acknowledgements

M.L. is supported by a career position funded by the Karolinska Institutet, Sweden, faculty; a Cancerfonden Project grant (22 2033 Pj); and a Swedish Research Council (Vetenskapsrådet) starting grant (2019-01961). C.S. is supported by a Novo Nordisk Foundation Postdoctoral Fellowship (NNF19OC0055700). A.L. is supported by the Olle Engkvist Foundation (to M.L.).

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  1. These authors contributed equally: Cagla Sahin, Axel Leppert.

Authors and Affiliations

  1. Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet–Biomedicum, Solna, Sweden

    Cagla Sahin, Axel Leppert & Michael Landreh

  2. Structural Biology and NMR laboratory and the Linderstrøm–Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark

    Cagla Sahin

  3. Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden

    Michael Landreh

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Sahin, C., Leppert, A. & Landreh, M. Advances in mass spectrometry to unravel the structure and function of protein condensates. Nat Protoc 18, 3653–3661 (2023). https://doi.org/10.1038/s41596-023-00900-0

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