Extended Data Fig. 8: Structural determinants for dsRNA binding.
From: Structural insights into double-stranded RNA recognition and transport by SID-1
a to c, Representative cryo-EM micrographs and 2D averages of SID1 (a), hSIDT1 (b), and hSIDT2 with or without dsRNA added to the sample. Yellow arrows indicate dsRNA. Scale bars represent 50 nm in EM micrographs and 10 nm in 2D averages, respectively. d, Key residues responsible for dsRNA binding in the ECD of SID-1. e and f, Residues at equilibrium positions of ECD of SID-1 (panel d) are highlighted in the ECD of hSIDT1 (e) and hSIDT2 (f). g, Superposition of SID-1apo and dsRNA bound SID-1. SID-1apo is colored in gray, the ECDI, ECDII, and TMD of dsRNA-bound SID-1 are colored in blue, pink, and green, respectively. (h to j) A closer look at the conformational changes in ECDI (h), ECDI and ECDII linker (i), and ECDII (j) between SID-1apo and dsRNA-bound protomer of SID-1dsRNA. Red arrows indicate local conformational shifts. (k to m) A closer look at the conformational changes in ECDI (k), ECDI and ECDII linker (l), and ECDII (m) between SID-1apo and dsRNA-unbound protomer of SID-1dsRNA.
