6B1G

Solution structure of TDP-43 N-terminal domain dimer.

Summary for 6B1G

• Entry DOI: 10.2210/pdb6b1g/pdb
• NMR Information: BMRB: 30345
• Descriptor: TAR DNA-binding protein 43, S48E Mutant, TAR DNA-binding protein 43, Y4R Mutant (2 entities in total)
• Functional Keywords: tdp-43, amyotrophic lateral sclerosis, protein aggregation, rna binding protein, protein self-assembly, dimerization, structural protein
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 2
• Total formula weight: 18440.65

Authors

Naik, M.T.,Wang, A.,Conicella, A.,Fawzi, N.L. (deposition date: 2017-09-18, release date: 2018-02-28, Last modification date: 2024-05-01)

Primary citation

Wang, A.,Conicella, A.E.,Schmidt, H.B.,Martin, E.W.,Rhoads, S.N.,Reeb, A.N.,Nourse, A.,Ramirez Montero, D.,Ryan, V.H.,Rohatgi, R.,Shewmaker, F.,Naik, M.T.,Mittag, T.,Ayala, Y.M.,Fawzi, N.L.
A single N-terminal phosphomimic disrupts TDP-43 polymerization, phase separation, and RNA splicing.
EMBO J., 37:-, 2018

PubMed Abstract: TDP-43 is an RNA-binding protein active in splicing that concentrates into membraneless ribonucleoprotein granules and forms aggregates in amyotrophic lateral sclerosis (ALS) and Alzheimer's disease. Although best known for its predominantly disordered C-terminal domain which mediates ALS inclusions, TDP-43 has a globular N-terminal domain (NTD). Here, we show that TDP-43 NTD assembles into head-to-tail linear chains and that phosphomimetic substitution at S48 disrupts TDP-43 polymeric assembly, discourages liquid-liquid phase separation (LLPS) , fluidizes liquid-liquid phase separated nuclear TDP-43 reporter constructs in cells, and disrupts RNA splicing activity. Finally, we present the solution NMR structure of a head-to-tail NTD dimer comprised of two engineered variants that allow saturation of the native polymerization interface while disrupting higher-order polymerization. These data provide structural detail for the established mechanistic role of the well-folded TDP-43 NTD in splicing and link this function to LLPS. In addition, the fusion-tag solubilized, recombinant form of TDP-43 full-length protein developed here will enable future phase separation and biochemical assays on TDP-43 function and interactions that have been hampered in the past by TDP-43 aggregation.

PubMed: 29438978
DOI: 10.15252/embj.201797452

Experimental method

SOLUTION NMR