Fig. 5
From: Structural basis for membrane tethering by a bacterial dynamin-like pair
Cj-DLP1/2tetramer oligomerisation and catalysis. a Cartoon showing Cj-DLP1 and Cj-DLP2 heterodimerisation mechanism. The N-terminal Helix 1 of Cj-DLP2 inserts into a groove within Cj-DLP1AD. Right panel shows zoom of left panel box. b SEC-MALS shows that truncation of Cj-DLP1AD or Cj-DLP2H1 abolishes tetramer formation. c, Schematic model of Cj-DLP1/2tetramer when in a solution state, rather than crystalline. The position of each Cj-DLP1 subunit relative to Cj-DLP2 has been chosen arbitrarily to highlight the 9 amino acid random coil linker. Crossed arrows indicate regions of high flexibility. d Histogram showing a structure-based molecular dynamics (MD) simulation of the Cj-DLP1/2tetramer in c. The Cj-DLP2linker is of sufficient length for GTPase heterodimerisation to occur. The two G-domain pairs transition between apo state in A, a mix of apo state and G-dimer in B and C, or G-dimer in D. e GTPase assays show that Cj-DLP1/2tetramer exhibits significant assembly stimulated turnover which is a known catalytic consequence of G-dimerisation. 1 or 2 µM protein concentration was used for tetrameric or monomeric species, respectively. Data represent mean ± standard deviation from 2 independent experiments. f Model of Cj-DLP1/2tetramer G-dimerisation based on data presented in d and e. Note that the geometry of the linker allows no other combination of G-dimerisation to occur within Cj-DLP1/2tetramer in the observed conformations
