Identifying the function of alternatively spliced TDP43 isoforms and contribution to disease

项目总结

PROJECT SUMMARY Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are related, often comorbid, neurodegenerative disorders with no available disease-modifying therapies. In over 95% of ALS patients, and 50% of FTD patients, affected neurons exhibit cytoplasmic mislocalization and accumulation of TDP43 (transactive response element DNA/RNA binding protein, 43 kDa). Mutations in TARDBP, the gene encoding TDP43, also cause familial forms of ALS and FTD, highlighting an integral contribution of TDP43 to these conditions. Even so, the mechanisms underlying TDP43 mislocalization in disease remain unclear. Recent evidence from our laboratory suggests that TDP43 mislocalization may be due to the production of alternatively spliced, shortened (s)TDP43 isoforms that are actively exported from the nucleus and prone to aggregation. sTDP43 isoforms are also evolutionarily conserved, but their regulation and function remain fundamentally unknown. This proposal seeks to elucidate the distinct function of sTDP43 isoforms and their potential contribution to disease by (i) defining the native transcript and protein interactors for sTDP43; and (ii) investigating a potential role for sTDP43 in regulating RNA stability. In so doing, these studies may reveal new pathways responsible for TDP43 mislocalization and neurodegeneration ALS and FTD. Additionally, it will enable me to develop essential skills in bioinformatics, proteomics, experimental design, data analysis, and scientific communication that will be critical for my success in my intended career as an independent investigator focused on the molecular underpinnings of neurodegeneration.