TY - JOUR
T1 - Real-Time Visualization of Dynamin-Catalyzed Membrane Fission and Vesicle Release
AU - Pucadyil, Thomas J.
AU - Schmid, Sandra L.
N1 - Funding Information:
We acknowledge Malcolm R. Wood for help with electron microscopy, Vadim Frolov for help with the membrane tether-pulling experiments, and Sharmistha Acharya and Marilyn Leonard for technical assistance. We thank William Balch, Vadim Frolov, Shanti Kalipatnapu, Allen Liu, Rajesh Ramachandran, and Joshua Zimmerberg for discussions and critical comments on the manuscript. This work is supported by grants from the National Institutes of Health to S.L.S (R01.GM042455 and R37.MH61345). T.J.P. is a fellow of The Leukemia and Lymphoma Society. This is The Scripps Research Institute manuscript number 19489.
PY - 2008/12/26
Y1 - 2008/12/26
N2 - The GTPase dynamin assembles at the necks of budded vesicles in vivo and functions in membrane fission. We have developed fluid supported bilayers with excess membrane reservoir, (SUPER) templates, to assay vesicle formation and membrane fission. Consistent with previous studies, in the absence of GTP, dynamin assembles in spirals, forming long membrane tubules. GTP addition triggers disassembly, but not membrane fission, arguing against models in which fission is mediated by concerted and global GTP-driven conformational changes. In contrast, under physiological conditions in the constant presence of GTP, dynamin mediates membrane fission. Under these conditions, fluorescently labeled dynamin cooperatively organizes into self-limited assemblies that continuously cycle at the membrane and drive vesicle release. When visualized at the necks of emergent vesicles, self-limited dynamin assemblies display intensity fluctuations and persist for variable time periods before fission. Thus, self-limited assemblies of dynamin generated in the constant presence of GTP catalyze membrane fission.
AB - The GTPase dynamin assembles at the necks of budded vesicles in vivo and functions in membrane fission. We have developed fluid supported bilayers with excess membrane reservoir, (SUPER) templates, to assay vesicle formation and membrane fission. Consistent with previous studies, in the absence of GTP, dynamin assembles in spirals, forming long membrane tubules. GTP addition triggers disassembly, but not membrane fission, arguing against models in which fission is mediated by concerted and global GTP-driven conformational changes. In contrast, under physiological conditions in the constant presence of GTP, dynamin mediates membrane fission. Under these conditions, fluorescently labeled dynamin cooperatively organizes into self-limited assemblies that continuously cycle at the membrane and drive vesicle release. When visualized at the necks of emergent vesicles, self-limited dynamin assemblies display intensity fluctuations and persist for variable time periods before fission. Thus, self-limited assemblies of dynamin generated in the constant presence of GTP catalyze membrane fission.
KW - CELLBIO
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U2 - 10.1016/j.cell.2008.11.020
DO - 10.1016/j.cell.2008.11.020
M3 - Article
C2 - 19084268
AN - SCOPUS:57649238675
VL - 135
SP - 1263
EP - 1275
JO - Cell
JF - Cell
SN - 0092-8674
IS - 7
ER -