Fig. 2. The binary complex has more WT CF molecules than the ternary complex.
a, b SEC-MALS analysis of the binary CF-C8FGLG complex, with corresponding SDS-PAGE analysis in (b) for the peak fractions in (a). The experiments were repeated twice with similar results. Source data are provided as a Source Data file. c The pipes-and-planks and ribbon diagrams illustrate the crystal structure of the binary CF-C8FGLG complex. The C8FGLG layer/tetramer and the 1st, 2nd, and 3rd WT CF layers/trimers are highlighted by white, dark gray, gray, and cyan lines, respectively, while the CBS for binding the cFLIP molecule CFo and the Casp-8 molecule C8a are highlighted by orange and red lines, respectively. The ball-and-ribbon diagram depicts the spatial relationship of individual DEDs with the type I, II, and III connectivity, represented by ribbons generated by the PyMOL program version 1.8.2.1, connecting the spatially conserved Cα atoms of every two adjacent DEDs. Each conserved Cα atom, representing DEDs, is shown as a ball, including those of Casp-8 residues L62 and L162, and cFLIP residues L55 and L152. A red arrow indicates a space left by the absence of FADD DED, predicted as a dashed ball. Please note that all the spatially conserved tDEDs in different representations, including ribbons, balls, and hexagons, in different Figs., would receive the same chain ID and color. Please refer to the legend of Fig. 1c for details on the molecular color schemes used. C8d1 denotes DED1 of Casp-8tDED chain d, while CFf represents cFLIPtDED chain f. d The crystal structure of the CF-C8FGLG complex exhibits a size and shape comparable to the envelop derived from the SAXS data of the same complex.