Fus protein, also known as fused in sarcoma protein, is a multifunctional RNA-binding protein that plays a crucial role in various cellular processes, including transcription regulation, RNA splicing, and mRNA transport. Mutations in the Fus gene have been linked to neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), indicating its importance in maintaining neuronal health and function. Research on Fus protein focuses on understanding its normal physiological functions, as well as its role in disease pathogenesis, in order to develop potential therapeutic strategies for ALS and FTD.