A Screen for Membrane Fission Catalysts Identifies the ATPase EHD1

Membrane
fission manifests during cell division, synaptic transmission,
vesicular transport, and organelle biogenesis, yet identifying proteins
that catalyze fission remains a challenge. Using a facile and robust
assay system of supported membrane tubes in a microscopic screen that
directly monitors membrane tube scission, we detect robust GTP- and
ATP-dependent as well as nucleotide-independent fission activity in
the brain cytosol. Using previously established interacting partner
proteins as bait for pulldowns, we attribute the GTP-dependent fission
activity to dynamin. Biochemical fractionation followed by mass spectrometric
analyses identifies the Eps15-homology domain-containing protein1
(EHD1) as a novel ATP-dependent membrane fission catalyst. Together,
our approach establishes an experimental workflow for the discovery
of novel membrane fission catalysts.