TY - JOUR
T1 - The endosomal sorting complex ESCRT-II mediates the assembly and architecture of ESCRT-III helices
AU - Henne, William Mike
AU - Buchkovich, Nicholas J.
AU - Zhao, Yingying
AU - Emr, Scott D.
N1 - Funding Information:
W.M.H. is supported by a Sam and Nancy Fleming Research Fellowship. N.J.B. is supported by an American Cancer Society Postdoctoral Fellowship (PF-12-062-01-DMC). We thank Beverly Wendland for the Mup1-pHluorin integration plasmid and Roger Williams for the ESCRT-II expression construct. The authors also thank Neil Adige and Bret Judson for all technical expertise. We also thank Chris Stefan, Jason MacGurn, Jeremy Thorner, Tony Bretscher, Chris Fromme, Gerald Feigenson, David Teis, Suraj Saksena, Jeanne Quirit, and Abbie Davies for helpful discussions.
PY - 2012/10/12
Y1 - 2012/10/12
N2 - The endosomal sorting complexes required for transport (ESCRTs) constitute hetero-oligomeric machines that mediate topologically similar membrane-sculpting processes, including cytokinesis, retroviral egress, and multivesicular body (MVB) biogenesis. Although ESCRT-III drives membrane remodeling that creates MVBs, its structure and the mechanism of vesicle formation are unclear. Using electron microscopy, we visualize an ESCRT-II:ESCRT-III supercomplex and propose how it mediates vesicle formation. We define conformational changes that activate ESCRT-III subunit Snf7 and show that it assembles into spiraling ∼9 nm protofilaments on lipid monolayers. A high-content flow cytometry assay further demonstrates that mutations halting ESCRT-III assembly block ESCRT function. Strikingly, the addition of Vps24 and Vps2 transforms flat Snf7 spirals into membrane-sculpting helices. Finally, we show that ESCRT-II and ESCRT-III coassemble into ∼65 nm diameter rings indicative of a cargo-sequestering supercomplex. We propose that ESCRT-III has distinct architectural stages that are modulated by ESCRT-II to mediate cargo capture and vesicle formation by ordered assembly.
AB - The endosomal sorting complexes required for transport (ESCRTs) constitute hetero-oligomeric machines that mediate topologically similar membrane-sculpting processes, including cytokinesis, retroviral egress, and multivesicular body (MVB) biogenesis. Although ESCRT-III drives membrane remodeling that creates MVBs, its structure and the mechanism of vesicle formation are unclear. Using electron microscopy, we visualize an ESCRT-II:ESCRT-III supercomplex and propose how it mediates vesicle formation. We define conformational changes that activate ESCRT-III subunit Snf7 and show that it assembles into spiraling ∼9 nm protofilaments on lipid monolayers. A high-content flow cytometry assay further demonstrates that mutations halting ESCRT-III assembly block ESCRT function. Strikingly, the addition of Vps24 and Vps2 transforms flat Snf7 spirals into membrane-sculpting helices. Finally, we show that ESCRT-II and ESCRT-III coassemble into ∼65 nm diameter rings indicative of a cargo-sequestering supercomplex. We propose that ESCRT-III has distinct architectural stages that are modulated by ESCRT-II to mediate cargo capture and vesicle formation by ordered assembly.
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U2 - 10.1016/j.cell.2012.08.039
DO - 10.1016/j.cell.2012.08.039
M3 - Article
C2 - 23063125
AN - SCOPUS:84867548612
SN - 0092-8674
VL - 151
SP - 356
EP - 371
JO - Cell
JF - Cell
IS - 2
ER -