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A Screen for Membrane Fission Catalysts Identifies the ATPase EHD1.

ABSTRACT: 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.

SUBMITTER: Kamerkar SC

PROVIDER: S-EPMC6327249 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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A Screen for Membrane Fission Catalysts Identifies the ATPase EHD1.

Kamerkar Sukrut C SC Roy Krishnendu K Bhattacharyya Soumya S Pucadyil Thomas J TJ

Biochemistry 20181116 1

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 b ...[more]

PMID: 30403133

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