Dynamic remodeling of the dynamin helix during membrane constriction Academic Article uri icon

Overview

MeSH Major

  • Bacterial Outer Membrane Proteins
  • Microscopy, Atomic Force
  • Phospholipases A1
  • Phospholipids

abstract

  • Dynamin is a dimeric GTPase that assembles into a helix around the neck of endocytic buds. Upon GTP hydrolysis, dynamin breaks these necks, a reaction called membrane fission. Fission requires dynamin to first constrict the membrane. It is unclear, however, how dynamin helix constriction works. Here we undertake a direct high-speed atomic force microscopy imaging analysis to visualize the constriction of single dynamin-coated membrane tubules. We show GTP-induced dynamic rearrangements of the dynamin helix turns: the average distances between turns reduce with GTP hydrolysis. These distances vary, however, over time because helical turns were observed to transiently pair and dissociate. At fission sites, these cycles of association and dissociation were correlated with relative lateral displacement of the turns and constriction. Our findings show relative longitudinal and lateral displacements of helical turns related to constriction. Our work highlights the potential of high-speed atomic force microscopy for the observation of mechanochemical proteins onto membranes during action at almost molecular resolution.

publication date

  • May 23, 2017

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC5448220

Digital Object Identifier (DOI)

  • 10.1073/pnas.1619578114

PubMed ID

  • 28484031

Additional Document Info

start page

  • 5449

end page

  • 5454

volume

  • 114

number

  • 21