Fig. 1

Drp1 oligomerization-related changes. a Secondary structure of the Drp1 peptide chain and its functional domains. The five motifs in the GTPase domain are essential features of Drp1, which is a large GTPase protein in the dynamin superfamily. These features include the G1 motif (32–39 aa), G2 motif (58–60 aa), 80-loop (72–87 aa), G3 motif (146–149 aa), G4 motif (215–218 aa), and G5 motif (245–248 aa). The 80-loop is a unique structure that distinguishes Drp1 from other dynamin superfamily members. b Tertiary structure of the Drp1 monomer. The bundle signaling element (BSE) conformation comprises three helix bundles (α1^B, α2^B, and α3^B), which mainly regulate the nucleotide-dependent oligomeric changes from the GTPase domain to the Stalk region. The Stalk conformation comprises elongated, antiparallel four-helix bundles; the first three belong to the MD domain (α1^S, α2^S, and α3^S). The α1^S helix is further subdivided into α1N^S, α1M^S, and α1C^S, which are connected by two loops (L1N^S and L1C^S). α4^S belongs to the GTPase effector domain (GED) domain and connects with α3^S via L4.^S after crossing the B-insert domain. c Quaternary conformation of the Drp1 dimer filament. Side and top views of the Drp1 dimer that assembles via the central Stalk interface-2. d Quaternary conformation of the Drp1 tetramer network. All GTPase domains locate on the same side, and all B-insert domains locate on the opposite side in the Drp1 tetramer conformation. e Quaternary conformation of the Drp1 polymer loop. All B-insert regions locate inside the Drp1 polymer loop, which is responsible for recognizing and interacting with mitochondrial membrane proteins. Drp1 Dynamin-related protein 1