Cryo-EM Studies of Drp1 Reveal Cardiolipin Interactions that Activate the Helical Oligomer
| Autor: | Christopher A. Francy, Chris Fröhlich, Ryan W. Clinton, Colleen Murphy, Jason A. Mears |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Dynamins Models Molecular endocrine system Cardiolipins lcsh:Medicine Quantitative Structure-Activity Relationship GTPase Biology Protein Structure Secondary Article GTP Phosphohydrolases Mitochondrial Proteins 03 medical and health sciences chemistry.chemical_compound Protein structure Membrane fission Cardiolipin Protein Interaction Domains and Motifs lcsh:Science Lipid bilayer Multidisciplinary Nanotubes Protein Stability lcsh:R Cryoelectron Microscopy Cell biology Mitochondria 030104 developmental biology Membrane chemistry Enzyme mechanisms lcsh:Q Mitochondrial fission Protein Multimerization Bacterial outer membrane Microtubule-Associated Proteins Protein Binding |
| Zdroj: | Scientific Reports Scientific Reports, Vol 7, Iss 1, Pp 1-12 (2017) |
| ISSN: | 2045-2322 |
| Popis: | Dynamins are mechano-chemical GTPases involved in the remodeling of cellular membranes. In this study, we have investigated the mechanism of dynamin-related protein 1 (Drp1), a key mediator of mitochondrial fission. To date, it is unclear how Drp1 assembles on the mitochondrial outer membrane in response to different lipid signals to induce membrane fission. Here, we present cryo-EM structures of Drp1 helices on nanotubes with distinct lipid compositions to mimic membrane interactions with the fission machinery. These Drp1 polymers assemble exclusively through stalk and G-domain dimerizations, which generates an expanded helical symmetry when compared to other dynamins. Interestingly, we found the characteristic gap between Drp1 and the lipid bilayer was lost when the mitochondrial specific lipid cardiolipin was present, as Drp1 directly interacted with the membrane. Moreover, this interaction leads to a change in the helical structure, which alters G-domain interactions to enhance GTPase activity. These results demonstrate how lipid cues at the mitochondrial outer membrane (MOM) can alter Drp1 structure to activate the fission machinery. |
| Databáze: | OpenAIRE |
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