Fig. 2

A conserved dimerization mode via the G interface in dynamin and septin GTPases. The overall architecture of the parallel GTPase domain dimer of Irga6 is related to that of other dynamin and septin superfamily proteins. The following structures are shown in cylinder representations, in similar orientations of their GTPase domains: a the GMPPNP-bound Irga6 dimer, b the GDP-AlF₄ ^--bound dynamin 1 GTPase-minimal BSE construct [pdb 2X2E], c the GDP-bound atlastin 1 dimer [pdb 3Q5E], d the GDP-AlF₃- bound GBP1 GTPase domain dimer [pdb 2B92], e the BDLP dimer bound to GDP [pdb 2J68] and f the GTP-bound GIMAP2 dimer [pdb 2XTN]. The GTPase domains of the left molecules are shown in orange, helical domains or extensions in blue. Nucleotide, Mg²⁺ (green) and AlF₄ ^- are shown in sphere representation, the buried interface sizes per molecule are indicated on the right. Irga6 immunity-related GTPase 6, GMPPNP 5'-guanylyl imidodiphosphate, GTP guanosine-triphosphate, BDLP bacterial dynamin like protein, GIMAP2, GTPase of immunity associated protein 2