Fig. 1: Egr forms hetero-hexamers with both Grnd and Wgn.

A Top: Egr domain structure comprising an N-terminal intracellular region, a transmembrane (TM) helix, and an extracellular portion with the TNF domain. The cleavage site recognized by TACE is indicated as a red bar. Middle: Domain structure of Wgn with an N-terminal cysteine-rich domain (CRD), a TM and an intracellular region with a coiled-coil. Bottom: Domain structure of Grnd with an N-terminal extracellular region containing a CRD, followed by a TM domain, and an intracellular region containing the Veli and Traf2 binding domains. B, C SEC elution profile of the complex formed between Egr^146–409 and Grnd^30–97 mixed at 30 μM equimolar concentration, and Egr^146–409 and Wgn^78–201 mixed at 200 μM:800 μM concentrations, with Coomassie-stained SDS-PAGE of the eluted fractions corresponding to the horizontal black bar. The elution profile of globular markers is reported as a dashed grey line. Individual runs of Egr, Grnd and Wgn are shown for comparison. Results of SEC runs and SDS-PAGES were confirmed by successful replicate experiments. D Static-Light-Scattering profiles of Egr^146–409, Grnd^30–97, Wgn^78–201, and the two complexes formed by Egr^146–409:Grnd^30–97 and Egr^146–409:Wgn^78–201. The UV absorbance trace is shown in blue (left axis) and the measured MW in red (right axis). E ITC measurements of the binding affinity between Egr^146–409 and Grnd^30–97 (left) and Egr^146–409 and Wgn^78–201(right). The K_D is reported as mean ± error fitting of the ITC data with the isotherm (black line). Both reactions are exothermic. Uncropped images of SDS-PAGE gels and immunoblots are provided in Supplementary Fig. 6.