Fig. 3.

Superposition with known structures of related nsp7-nsp8 complexes Structure of the SARS-CoV-2 nsp7-nsp8 dimer presented in this study (pdb code 6yhu) was superposed with the hexameric structure of the feline CoV nsp7-nsp8 4:2 complex (A, pdb code 3ub0) or hexadecameric structure of the SARS-CoV 8:8 nsp7-nsp8 complex (B, pdb code 2ahm) or the cryo-electron microscopic structure of the SARS-CoV-2 RNA-dependent RNA polymerase complex composed of the nsp7, nsp8, and nsp12 proteins bound to two turns of RNA template-product duplex (C, pdb code 6yyt). The nsp7 and nsp8 proteins from the crystal structure are colored in blue and yellow, respectively. The nsp7 and nsp8 proteins and RNA from the cryo-EM structure are depicted in grey, while the nsp12 protein is colored in red. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)