Electric dipole moment drives the dynamics of the TNFR1 complex I signalosome
Article Date: 01 April 2026
Article URL: https://www.nature.com/articles/s41586-026-10304-1
Article Image: https://www.nature.com/articles/s41586-026-10304-1/figures/1
Summary
This study uses cryo-electron microscopy, biochemical assays and cellular experiments to reveal how electrostatic properties — specifically the cumulative electric dipole moment (EDM) of death-domain (DD) assemblies — control the assembly and timed disassembly of the TNFR1 Complex I signalosome. The authors solved high-resolution structures of TNFR1-DD, TRADD-DD and RIPK1-DD helical filaments and a ternary DD complex, and show that pentameric DD layers assemble through complementary charge interactions. Importantly, the cumulative EDM of RIPK1-DD layers produces repulsive forces that drive the timed release of RIPK1 from the membrane-associated complex, thereby gating downstream signalling. Mutational perturbation of surface charge (and thus EDM) altered filament dynamics and TNF-induced gene expression, supporting a mechanistic role for electrostatics in Complex I dynamics. Experimental data and maps are deposited in PDB/EMDB (examples: PDB 9V9C, 9VGD, 9V9E, 9VIN; EMD-64869, EMD-65047, EMD-64870, EMD-65094).
Key Points
- Cryo-EM structures of TNFR1-DD, TRADD-DD and RIPK1-DD filaments and a ternary DD complex reveal pentamer-layered assemblies driven by electrostatic complementarity.
- Charge complementarity between the “top” and “bottom” faces of DD pentamers seeds ordered recruitment of adaptors (TRADD) and RIPK1 to receptor DD layers.
- The cumulative electric dipole moment of RIPK1-DD layers generates repulsive forces that promote timed dissociation of RIPK1 oligomers from Complex I, enabling downstream signalling activation.
- Targeted mutations that alter RIPK1-DD EDM change filament morphology, puncta lifetime in cells and TNF-induced transcriptional responses, linking structure to function.
- Modelling indicates extracellular geometry limits receptor clustering size, while the intracellular linkers and DD assemblies accommodate high-order intracellular complexes.
- Data have been deposited in public repositories (PDB and EMDB) and multiple functional assays (EM, live-cell imaging, RNA-seq, qRT-PCR) corroborate the structural findings.
Context and relevance
This work integrates structural biology with cell biology to explain how physical electrostatic properties — not just specific binding interfaces — control the timing and dynamics of a major inflammatory signalling hub. TNFR1 signalling decides cell fate between survival, inflammation and death; understanding the molecular timing mechanism has implications for inflammatory disease biology and for targeting RIPK1-mediated pathways therapeutically. The EDM-driven timing mechanism may be a wider principle applicable to other DD-containing signalosomes (for example MyD88-IRAK or Fas-FADD assemblies).
Why should I read this?
Short, sharp: this paper shows that electric dipoles — not just protein binding surfaces — act like a built-in timer for TNFR1 Complex I. If you work on TNF signalling, death-domain assemblies or targeted inhibitors of RIPK1, it’s genuinely useful and clever. The structures, functional mutants and deposited datasets save you time and give concrete targets for follow-up experiments or drug ideas.
Author style
Punchy: the authors combine crisp cryo-EM structures with clean functional readouts to make a strong case that electrostatics actively regulate signalosome dynamics. If the topic matters to you, dig into the figures and methods — there’s clear mechanistic detail and datasets you can reuse.