MISC

2002年3月

Phosphatidylinositol 4,5-bisphosphate stimulates vesicle formation from liposomes by brain cytosol

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
  • M Kinuta
  • ,
  • H Yamada
  • ,
  • T Abe
  • ,
  • M Watanabe
  • ,
  • SA Li
  • ,
  • A Kamitani
  • ,
  • T Yasuda
  • ,
  • T Matsukawa
  • ,
  • H Kumon
  • ,
  • K Takei

99
5
開始ページ
2842
終了ページ
2847
記述言語
英語
掲載種別
DOI
10.1073/pnas.261715599
出版者・発行元
NATL ACAD SCIENCES

As a step toward the elucidation of mechanisms in vesicle budding, a cell-free assay that measures cytosol-induced vesicle generation from liposomes was established. This assay then was used to explore the role of phosphoinositides in vesicle formation. Liposomes incubated with brain cytosol in the presence of ATP and GTP massively generated small vesicles, as assessed both quantitatively and qualitatively by a dynamic light-scattering assay. Both ATP and GTP were required. Vesicle formation was inhibited greatly by the immunodepletion of dynamin 1 from the cytosol, indicating a major contribution of this GTPase in this reaction and suggesting that it mimics endocytic vesicle fission. Increasing the concentration Of L-alpha-phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P-2] but not of L-alpha-phosphatidylinositol 4-monophosphate or L-alpha-phosphatidylinositol in the lipid membranes enhanced vesicle formation. Lipid analysis revealed rapid degradation of PtdIns(4,5)P-2 to L-alpha-phosphatidylinositol during the incubation with the reaction reaching a maximum within 5 sec, whereas vesicle formation proceeded with a longer time course. PtdIns(4,5)P-2 degradation was independent of vesicle formation and occurred also in the presence of guanosine 5'-O-(thiotriphosphate), where few vesicle formations occurred. These results suggest that PtdIns(4,5)P-2 plays a critical role in the early step of vesicle formation, possibly in the recruitment of coats and fission factors to membranes.


リンク情報
DOI
https://doi.org/10.1073/pnas.261715599
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000174284600047&DestApp=WOS_CPL
ID情報
  • DOI : 10.1073/pnas.261715599
  • ISSN : 0027-8424
  • Web of Science ID : WOS:000174284600047

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