The FXR1 protein regulates the stability and translation of a number of RNA molecules and plays an important role in the regulation of cellular processes under normal conditions and stress. In particular, this protein is known to be a negative regulator of the key proinflammatory cytokine TNF alpha. We had previously shown that FXR1 functioned in the amyloid form in neurons of the brain of jawed vertebrates. Under stress conditions, FXR1 is incorporated into stress granules in some cell lines, but such studies have not been conducted for neuronal cells. Here, we showed the ability of the FXR1 protein to form cytoplasmic granules in a neuroblastoma cell line under various types of stress. This protein colocalizes with core proteins of neuronal stress granules upon heat shock and sodium arsenite treatment. We also showed that FXR1 colocalizes with anti-amyloid antibodies OC under both normal and stress conditions. Given that stress granules are dynamic structures, we propose that amyloid FXR1-containing RNP particles interact with other stress granule proteins through weak intermolecular hydrogen bonds. Using a yeast model system, we found that FXR1 colocalizes and physically interacts with stress granule proteins such as TIA-1, FMRP, FXR2, and SFPQ. Overall, our results provide new insights into the role of the RNA-binding protein FXR1 in neuronal stress response. We believe that FXR1 inactivation in neuronal stress granules can contribute to an increase in the level of the proinflammatory cytokine TNF alpha in neurodegenerative diseases.

Original languageEnglish
Pages (from-to)1-16
Number of pages16
JournalPrion
Volume19
Issue number1
Early online date24 May 2025
DOIs
StatePublished - Dec 2025

    Research areas

  • Amyloid/metabolism, Animals, Arsenites/pharmacology, Cell Line, Tumor, Cytoplasmic Granules/metabolism, Humans, Neurons/metabolism, RNA-Binding Proteins/metabolism, Sodium Compounds/pharmacology, Stress Granules/metabolism, Stress, Physiological, sodium arsenite, neurodegenerative disease, heat shock, RNA-binding proteins, functional amyloid, FXR1, TIA-1, neuroinflammation, stress granules, FRET

ID: 138864280