Open AccessDrp1 polymerization stabilizes curved tubular membranes similar to those of constricted mitochondria
Author(s) -
Begoña UgarteUribe,
Coline Prévost,
Kushal Kumar Das,
Patricia Bassereau,
Ana J. GarcíaSáez
Publication year - 2017
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.208603
Subject(s) - membrane curvature , biology , dynamin , gtpase , membrane , microbiology and biotechnology , mitochondrial fission , biophysics , mitochondrion , lipid bilayer , biochemistry , endocytosis , cell
Drp1, an 80-kDa mechanochemical GTPase of the dynamin superfamily, is required for mitochondrial division in mammals. Despite the role of Drp1 dysfunction in human disease, its molecular mechanism remains poorly understood. Here, we examined the effect of Drp1 as a minimal machinery on membrane curvature using tubes pulled from GUVs. We found that GTP promoted rapid rearrangement of Drp1 from a uniform distribution to discrete foci, in line with the assembly of Drp1 scaffolds at multiple nucleation sites around the lipid tube. Polymerized Drp1 preserved the membrane tube below the protein coat also in the absence of pulling forces, but did not induce spontaneous membrane fission. Strikingly, Drp1 polymers stabilized membrane curvatures similar to those of constricted mitochondria against pressure changes. Our findings support a new model for mitochondrial division where Drp1 mainly acts as a scaffold for membrane curvature stabilization, which sets it apart from other dynamin homologs.