Research Projects

Controlled gene expression is crucial for cellular homeostasis and its dysregulation often leads to pathological conditions. Fine-tuning of gene regulation is carried by RNA-binding proteins (RBPs) by altering mRNA localization, stability, and translation. The Fmr family of RBPs (consisting of Fmr1, Fxr1, and Fxr2) regulate post-transcriptional gene expression in neurons, and mutations in these proteins are associated to neurological disorders like Intellectual Disability (ID), Autism Spectrum Disorders (ASD), and schizophrenia. Fmr1 has been extensively characterized for its role in manifestation of Fragile X syndrome (FXS), a prominent genetic cause of ASD. However, the roles of its paralogues, Fxr1 and Fxr2, remain largely unexplored in the neuronal function despite their high expression levels. This project seeks to address gaps in our understanding of Fmr family protein-mediated gene regulation, particularly the spatiotemporal dynamics of translational regulation by Fmr1, Fxr1 and Fxr2 at single-molecule resolution. Our first objective is to unravel the spatiotemporal regulation of reporter mRNA translation by Fmr1, Fxr1 and Fxr2 in HeLa cells under physiological and stress conditions using a combination of tethering assay and SunTag imaging system. Our second objective is to identify overlapping and unique mRNA targets of Fmr1, Fxr1, and Fxr2 using enhanced CLIP-seq in differentiating neurons under healthy and stress conditions. Subsequently, few selected targets will be further characterized for any alteration in their localization and translation using single-molecule fluorescent in situ hybridization (smFISH) and immunofluorescence. Our final objective will be to combine both objectives and extract realtime spatiotemporal dynamics of translational regulation by Fmr family proteins from differentiating neurons under physiological and stress conditions. In addition, we will also investigate how the spatiotemporal dynamics of translational regulation is altered due to the expression of disease associated mutation/variants of these proteins. This study will provide insights into the spatiotemporal regulation of gene expression by Fmr1, Fxr1 and Fxr2 during neuronal differentiation, maturation, and its function in response to cellular stress, with potential implications for understanding their dysregulation in neurological disorders.