The oligomerization domains of the APC protein mediate liquid-liquid phase separation that is phosphorylation controlled

Shachar G. Bressler, Amit Mitrany, Alon Wenger, Inke Nathke (Lead / Corresponding author), Assaf Friedler (Lead / Corresponding author)

    Research output: Contribution to journalArticlepeer-review

    3 Citations (Scopus)
    49 Downloads (Pure)

    Abstract

    One of the most important properties of intrinsically disordered proteins is their ability to undergo liquid-liquid phase separation and form droplets. The Adenomatous Polyposis Coli (APC) protein is an IDP that plays a key role in Wnt signaling and mutations in Apc initiate cancer. APC forms droplets via its 20R domains and self-association domain (ASAD) and in the context of Axin. However, the mechanism involved is unknown. Here, we used peptides to study the molecular mechanism and regulation of APC droplet formation. We found that a peptide derived from the ASAD of APC-formed droplets. Peptide array screening showed that the ASAD bound other APC peptides corresponding to the 20R3 and 20R5 domains. We discovered that the 20R3/5 peptides also formed droplets by themselves and mapped specific residues within 20R3/5 that are necessary for droplet formation. When incubated together, the ASAD and 20R3/5 did not form droplets. Thus, the interaction of the ASAD with 20R3 and 20R5 may regulate the droplet formation as a means of regulating different cellular functions. Phosphorylation of 20R3 or 20R5 at specific residues prevented droplet formation of 20R3/5. Our results reveal that phosphorylation and the ability to undergo liquid-liquid phase separation, which are both important properties of intrinsically disordered proteins, are related to each other in APC. Phosphorylation inhibited the liquid-liquid phase separation of APC, acting as an ‘on-off’ switch for droplet formation. Phosphorylation may thus be a common mechanism regulating LLPS in intrinsically disordered proteins.
    Original languageEnglish
    Article number6478
    Number of pages17
    JournalInternational Journal of Molecular Sciences
    Volume24
    Issue number7
    Early online date30 Mar 2023
    DOIs
    Publication statusPublished - 1 Apr 2023

    Keywords

    • intrinsically disordered proteins
    • Adenomatous polyposis coli
    • liquid-liquid phase separation
    • post translational modifications
    • phosphorylation
    • adenomatous polyposis coli

    ASJC Scopus subject areas

    • Molecular Biology
    • Spectroscopy
    • Catalysis
    • Inorganic Chemistry
    • Computer Science Applications
    • Physical and Theoretical Chemistry
    • Organic Chemistry

    Fingerprint

    Dive into the research topics of 'The oligomerization domains of the APC protein mediate liquid-liquid phase separation that is phosphorylation controlled'. Together they form a unique fingerprint.

    Cite this