Nuclear-import receptors remodel the dilute phase to suppress phase transitions of RNA-binding proteins with prion-like domains.

ABSTRACT: RNA-binding proteins (RBPs) with prion-like domains, including FUS, hnRNPA1, and hnRNPA2, assemble into functional, metastable condensates that organize ribostasis, but can also transition into self-templating fibrils implicated in neurodegenerative proteinopathies such as amyotrophic lateral sclerosis (ALS). How nuclear-import receptors (NIRs) antagonize this pathological transition has remained unresolved. Here, we establish that NIRs regulate the phase behavior of prion-like cargos by remodeling the dilute phase. Quantitative analyses across length scales reveal that Karyopherin-β2 (Kapβ2) preferentially binds cargo in the dilute phase to lower the effective concentration of free RBPs thereby elevating the saturation concentration for phase separation and suppressing mesoscale clusterin

SUBMITTER: Linsenmeier M 

PROVIDER: S-EPMC12642399 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature