An in-depth review of the function of RNA-binding protein FXR1 in neurodevelopment

FMR1 autosomal homolog 1 (FXR1) is an RNA-binding protein that belongs to the Fragile X-related protein (FXR) family. FXR1 is critical for development, as its loss of function is intolerant in humans and results in neonatal death in mice. Although FXR1 is expressed widely including the brain, functional studies on FXR1 have been mostly performed in cancer cells. Limited studies have demonstrated the importance of FXR1 in the brain. In this review, we will focus on the roles of FXR1 in brain development and pathogenesis of brain disorders. We will summarize the current knowledge in FXR1 in the context of neural biology, including structural features, isoform diversity and nomenclature, expression patterns, post-translational modifications, regulatory mechanisms, and molecular functions. Overall, FXR1 emerges as an important regulator of RNA metabolism in the brain, with strong implications in neurodevelopmental and psychiatric disorders.