MISC

2006年5月

Membrane fusion by single influenza hemagglutinin trimers - Kinetic evidence from image analysis of hemagglutinin-reconstituted vesicles

JOURNAL OF BIOLOGICAL CHEMISTRY
  • M Imai
  • ,
  • T Mizuno
  • ,
  • K Kawasaki

281
18
開始ページ
12729
終了ページ
12735
記述言語
英語
掲載種別
DOI
10.1074/jbc.M600902200
出版者・発行元
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC

Influenza hemagglutinin, the receptor-binding and membrane fusion protein of the virus, is a prototypic model for studies of biological membrane fusion in general. To elucidate the minimum number of hemagglutinin trimers needed for fusion, the kinetics of fusion induced by reconstituted vesicles of hemagglutinin was studied by using single-vesicle image analysis. The surface density of hemagglutinin fusion-activity sites on the vesicles was varied, while keeping the surface density of receptor-binding activity sites constant, by co-reconstitution of the fusogenic form of hemagglutinin, HA(1,2), and the non-fusogenic form, HA(0), at various HA(1,2):(HA(1,2) + HA(0)) ratios. The rate of fusion between the hemagglutinin vesicles containing a fluorescent lipid probe, octadecylrhodamine B, and red blood cell ghost membranes was estimated from the time distribution of fusion events of single vesicles observed by fluorescence microscopy. The best fit of a log-log plot of fusion rate versus the surface density of HA(1,2) exhibited a slope of 0.85, strongly supporting the hypothesis that single hemagglutinin trimers are sufficient for fusion. When only HA(1,2) (without HA(0)) was reconstituted on vesicles, the dependence of fusion rate on the surface density of HA(1,2) was distinct from that for the HA(1,2)-HA(0) co-reconstitution. The latter result suggested interference with fusion activity by hemagglutinin-receptor binding, without having to assume a fusion mechanism involving multiple hemagglutinin trimers.

リンク情報
DOI
https://doi.org/10.1074/jbc.M600902200
CiNii Articles
http://ci.nii.ac.jp/naid/80019160249
PubMed
https://www.ncbi.nlm.nih.gov/pubmed/16505474
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000237134700065&DestApp=WOS_CPL
ID情報
  • DOI : 10.1074/jbc.M600902200
  • ISSN : 0021-9258
  • CiNii Articles ID : 80019160249
  • PubMed ID : 16505474
  • Web of Science ID : WOS:000237134700065

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