Molecular Dissection of FUS Points at Synergistic Effect of Low-Complexity Domains in Toxicity

Area of Science:

• Neurobiology
• Molecular Biology
• Genetics

Background:

• RNA-binding protein aggregation is a key feature of neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD).
• The FUS protein, implicated in ALS and FTLD, is known to aggregate in these conditions.

Purpose of the Study:

• To investigate the molecular interactions underlying FUS protein aggregation and toxicity.
• To elucidate the roles of different FUS protein domains in its pathological mechanisms.

Main Methods:

• Generation of a Drosophila melanogaster model to study FUS toxicity.
• Analysis of the synergistic effects between the N-terminal prion-like domain and the C-terminal arginine-rich domain of FUS.
• Investigation of the role of arginine residues in the C-terminal low-complexity domain in FUS maturation within cellular stress granules.

Main Results:

• A previously unrecognized synergistic toxicity was identified between the N-terminal prion-like domain and the C-terminal arginine-rich domain of FUS.
• Arginine residues within the C-terminal low-complexity domain are essential for the maturation of FUS in cellular stress granules.
• The prion-like domain's role in FUS aggregation is complemented by the function of arginine-rich domains.

Conclusions:

• Arginine-rich domains play a critical, previously underappreciated role in the pathology of RNA-binding proteins like FUS.
• Understanding these domain interactions offers new insights into the mechanisms of neurodegenerative diseases.
• The findings suggest potential therapeutic targets for ALS and FTLD related to FUS dysfunction.