Fig. 1: Overall architecture of Mrs2 and the closed conformation.
a, Topology of one Mrs2 monomer, with the NTD located in the matrix and TM1 and TM2 in the C terminus. The conserved GMN selective filter motif is located at the end of TM1 and two acidic residues (red dots) in the loop connecting TM1 and TM2. b, SEC profile of detergent-solubilized GFP-fused CtMrs2 (performed at least five independent times) and associated Coomassie-stained native PAGE (performed twice independently), indicating that CtMrs2 forms homopentamers. c, The 2.7-Å overall resolution cryo-EM density of the closed CtMrs2 homopentamer, shown from the membrane plane, from the intermembrane space and from the matrix (C5 map). Separate monomers are colored blue, orange, wheat, green and pink and the nanodisc is colored gray. d, Cartoon representation of the final structure of the closed CtMrs2 homopentamer with the same views and colors as in c. e, Surface electrostatics of the closed CtMrs2 homopentamer, shown from the membrane plane, from the intermembrane space and from the matrix.
