Dynamins are large superfamily GTPase proteins that are involved in various cellular processes including budding of transport vesicles, division of organelles, cytokinesis, and pathogen resistance. Dynamins are involved in scission (cleavage of the vesicle from the parent membrane) of nascent vesicles from parent membranes in eukaryotic cells. Dynamins interact directly with the lipid bilayer at the necks of clathrin-coated pits to sever and release coated vesicles. Dynamins contain five domains, including GTPase domain, middle domain, PH domain, GTPase effector domain (GED), and proline rich domain (PRD), while the dynamin-related proteins (DRPs) lack one or more of these domains or have additional domains. Dynamins and DRPs participate in a wide variety of cellular processes, including budding mitochondrial fission (mammalian Dlp1 and Saccharomyces cerevisiae Dnm1) and fusion (mammalian OPA1, S.cerevisiae Mgm1 and Schizosaccharomycespombe Msp1), vacuolar fission (S. cerevisiae Vps1), interferon-induced anti-viral protection (fish Mx proteins), plant cell cytokinesis and membrane fission (Arabidopsis thalianaDRP proteins), as well as pathogen resistance.