Extended Data Figure 5.

Architecture of Nprl2 and Nprl3. a. Structural model for Nprl2. Contact surfaces with Depdc5 and Nprl3 are pointed out by arrows. A long linker connects the Longin domain and the TINI domain with EM density shown in mesh. The atomic model for this linker is shown in d. b. Longin domain of Nprl2. A standard Longin domain from LST4 is shown for comparison. c. A strand-turn-strand motif (hairpin) is attached to the Longin domain of Nprl2, which mediates partial interaction with Depdc5. d. EM density map and atomic model for the linker connecting the Longin domain and the TINI domain (cf. the EM density in a). e. Structural model for the C-terminal domain (CTD) of Nprl2. f. Structural model for Nprl3. Contact surfaces with Nprl2 are indicated with arrows. g. Longin domain of Nprl3 and its overlap with the Longin domain of Nprl2. h. Structural model for the TINI domain of Nprl3 which connects its Longin domain with the C-terminal domains. i. Structural model for the Intermediary (INT) domain of Nprl3. j. Structural model for the C-terminal domain (CTD) of Nprl3. k-m. Interactions between Nprl2 and Nprl3. Three contact surfaces were identified that mediate the interactions between Nprl2 and Nprl3: the Longin domains of Nprl2 and Nprl3 (k), the TINI domain of Nprl2 and CTD of Nprl3 (I), and the CTD of Nprl2 and the INT domain of Nprl3 (m).