Native State Stabilization is an Effective Strategy to Inhibit TDP-43 Oligomerization and Fibrillogenesis

ABSTRACT: Transactive response DNA-binding protein 43 kDa (TDP-43) is a partially disordered nuclear protein that plays essential roles in RNA metabolism to maintain cellular homeostasis. In individuals with neurodegenerative diseases (NDDs), including Amyotrophic lateral Sclerosis (ALS), Alzheimer’s disease, and Parkinson’s disease, TDP-43 misfolds, aggregates, and accumulates in the form of neuronal cytoplasmic inclusions which are one of the primary diagnostic pathological biomarkers of NDDs, and key determinants of disease symptomology and progression. Therefore, preventing TDP-43 misfolding and aggregation has emerged as the most actively pursued therapeutic strategy to treat ALS and other NDDs, with an emphasis on targeting TDP-43 aggregates, neutralizing their activity, or promoting their clearance. We propose that the heterogeneity of the aggregation pathway and structural diversity of TDP-43 aggregates renders targeting TDP-43 pathologies with a single drug or antibody challenging or ineffective. Therefore, the most effective approach remains to prevent TDP-43 misfolding in the first place. In this work, we provide strong proof of concept evidence for native state stabilization of monomeric TDP-43 as a viable therapeutic strategy for treating TDP-43 proteinopathies. Firstly, we used Cryo-EM structures of TDP-43 fibrils to design mutations that mimic native post-translational modifications (TDP-43S333D/S342D) and disrupt TDP-43 self-assembly and phase separation resulting in the stabilization of monomeric TDP-43 for days at 4 ℃ or room temperature. Secondly, we show that the binding of native TDP-43 ligands (UG/TG-rich oligo-nucleotide ligands) stabilizes monomeric TDP-43 and prevents its aggregation, independent of direct binding to the aggregation-forming C-terminal domain. Thirdly, we show that the monomeric TDP-43 mutant could be induced to misfold and aggregate in a controlled manner, thus enabling the design of a high-throughput screening assay to identify native state stabilizers and modulators of TDP-43 aggregation, a goal that remained out of reach because of the high aggregation propensity of TDP-43, which have precluded drug discovery efforts to develop native state stabilizers of TDP-43. Altogether, these advances demonstrate that different structural domains in TDP-43 could be targeted and exploited for developing drugs that stabilize the native state of the protein and provides novel tools and assays that make this goal achievable and pave the way for identifying small molecule drugs to treat ALS and other TDP-43 proteinopathies.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human) Bacteria

SUBMITTER: Oscar Vadas  

LAB HEAD: Oscar Vadas

PROVIDER: PXD041160 | Pride | 2026-06-24

REPOSITORIES: Pride