Quantification and demonstration of the collective constriction-by-ratchet mechanism in the dynamin molecular motor.

ABSTRACT: Dynamin oligomerizes into helical filaments on tubular membrane templates and, through constriction, cleaves them in a GTPase-driven way. Structural observations of GTP-dependent cross-bridges between neighboring filament turns have led to the suggestion that dynamin operates as a molecular ratchet motor. However, the proof of such mechanism remains absent. Particularly, it is not known whether a powerful enough stroke is produced and how the motor modules would cooperate in the constriction process. Here, we characterized the dynamin motor modules by single-molecule Förster resonance energy transfer (smFRET) and found strong nucleotide-dependent conformational preferences. Integrating smFRET with molecular dynamics simulations allowed us to estimate the forces generated in a power stroke.

SUBMITTER: Ganichkin OM 

PROVIDER: S-EPMC8285958 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature