Fig. 3

Dimerization of MFN2_IM via the G domain. a The MFN2_IM dimer in GDP-bound state, with transparent surface representation. Molecule A is colored as in Fig. 1b, molecule B is in gray. GDP is shown as yellow spheres. b, Switch I configuration of MFN2_IM-GDP structure and MFN1_IM (Protein Data Bank code 5YEW) in the transition state. Switch I is colored yellow. The catalytic residues MFN2_IM(Thr130) and MFN1_IM(Thr109) are shown as ball-and-stick models. c Details of the G interface of MFN2_IM. Only one side of the G interface is shown for other involved residues except for the central dual salt bridges. d Structural comparison of MFN2_IM-GDP dimer with MFN1_IM-\({\mathrm{GDP}} \bullet {\mathrm{BeF}}_{3}^{-}\) dimer (PDB code 5YEW, left) and with MFN1_IM-GDP dimer (PDB code 5GOM, right). The structures are superimposed for one polypeptide chain (Mol A, shown in gray). The positions of the other chain (Mol B) showed a clear difference in orientation between MFN2_IM (pink) and MFN1_IM structures (light blue or green). Comparison of the G interface of MFN2_IM in the GDP-bound state (e) between MFN1_IM in the transition state (f PDB code 5YEW) and in the GDP-bound state (g PDB code 5GOM). Note the MFN2-specific Glu266-Lys307 salt bridge and the tighter trans association